LCOV - code coverage report
Current view: top level - gcc - cfgrtl.c (source / functions) Hit Total Coverage
Test: gcc.info Lines: 1860 2252 82.6 %
Date: 2020-03-28 11:57:23 Functions: 94 106 88.7 %
Legend: Lines: hit not hit | Branches: + taken - not taken # not executed Branches: 0 0 -

           Branch data     Line data    Source code
       1                 :            : /* Control flow graph manipulation code for GNU compiler.
       2                 :            :    Copyright (C) 1987-2020 Free Software Foundation, Inc.
       3                 :            : 
       4                 :            : This file is part of GCC.
       5                 :            : 
       6                 :            : GCC is free software; you can redistribute it and/or modify it under
       7                 :            : the terms of the GNU General Public License as published by the Free
       8                 :            : Software Foundation; either version 3, or (at your option) any later
       9                 :            : version.
      10                 :            : 
      11                 :            : GCC is distributed in the hope that it will be useful, but WITHOUT ANY
      12                 :            : WARRANTY; without even the implied warranty of MERCHANTABILITY or
      13                 :            : FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
      14                 :            : for more details.
      15                 :            : 
      16                 :            : You should have received a copy of the GNU General Public License
      17                 :            : along with GCC; see the file COPYING3.  If not see
      18                 :            : <http://www.gnu.org/licenses/>.  */
      19                 :            : 
      20                 :            : /* This file contains low level functions to manipulate the CFG and analyze it
      21                 :            :    that are aware of the RTL intermediate language.
      22                 :            : 
      23                 :            :    Available functionality:
      24                 :            :      - Basic CFG/RTL manipulation API documented in cfghooks.h
      25                 :            :      - CFG-aware instruction chain manipulation
      26                 :            :          delete_insn, delete_insn_chain
      27                 :            :      - Edge splitting and committing to edges
      28                 :            :          insert_insn_on_edge, commit_edge_insertions
      29                 :            :      - CFG updating after insn simplification
      30                 :            :          purge_dead_edges, purge_all_dead_edges
      31                 :            :      - CFG fixing after coarse manipulation
      32                 :            :         fixup_abnormal_edges
      33                 :            : 
      34                 :            :    Functions not supposed for generic use:
      35                 :            :      - Infrastructure to determine quickly basic block for insn
      36                 :            :          compute_bb_for_insn, update_bb_for_insn, set_block_for_insn,
      37                 :            :      - Edge redirection with updating and optimizing of insn chain
      38                 :            :          block_label, tidy_fallthru_edge, force_nonfallthru  */
      39                 :            : 
      40                 :            : #include "config.h"
      41                 :            : #include "system.h"
      42                 :            : #include "coretypes.h"
      43                 :            : #include "backend.h"
      44                 :            : #include "target.h"
      45                 :            : #include "rtl.h"
      46                 :            : #include "tree.h"
      47                 :            : #include "cfghooks.h"
      48                 :            : #include "df.h"
      49                 :            : #include "insn-config.h"
      50                 :            : #include "memmodel.h"
      51                 :            : #include "emit-rtl.h"
      52                 :            : #include "cfgrtl.h"
      53                 :            : #include "cfganal.h"
      54                 :            : #include "cfgbuild.h"
      55                 :            : #include "cfgcleanup.h"
      56                 :            : #include "bb-reorder.h"
      57                 :            : #include "rtl-error.h"
      58                 :            : #include "insn-attr.h"
      59                 :            : #include "dojump.h"
      60                 :            : #include "expr.h"
      61                 :            : #include "cfgloop.h"
      62                 :            : #include "tree-pass.h"
      63                 :            : #include "print-rtl.h"
      64                 :            : 
      65                 :            : /* Disable warnings about missing quoting in GCC diagnostics.  */
      66                 :            : #if __GNUC__ >= 10
      67                 :            : #  pragma GCC diagnostic push
      68                 :            : #  pragma GCC diagnostic ignored "-Wformat-diag"
      69                 :            : #endif
      70                 :            : 
      71                 :            : /* Holds the interesting leading and trailing notes for the function.
      72                 :            :    Only applicable if the CFG is in cfglayout mode.  */
      73                 :            : static GTY(()) rtx_insn *cfg_layout_function_footer;
      74                 :            : static GTY(()) rtx_insn *cfg_layout_function_header;
      75                 :            : 
      76                 :            : static rtx_insn *skip_insns_after_block (basic_block);
      77                 :            : static void record_effective_endpoints (void);
      78                 :            : static void fixup_reorder_chain (void);
      79                 :            : 
      80                 :            : void verify_insn_chain (void);
      81                 :            : static void fixup_fallthru_exit_predecessor (void);
      82                 :            : static int can_delete_note_p (const rtx_note *);
      83                 :            : static int can_delete_label_p (const rtx_code_label *);
      84                 :            : static basic_block rtl_split_edge (edge);
      85                 :            : static bool rtl_move_block_after (basic_block, basic_block);
      86                 :            : static int rtl_verify_flow_info (void);
      87                 :            : static basic_block cfg_layout_split_block (basic_block, void *);
      88                 :            : static edge cfg_layout_redirect_edge_and_branch (edge, basic_block);
      89                 :            : static basic_block cfg_layout_redirect_edge_and_branch_force (edge, basic_block);
      90                 :            : static void cfg_layout_delete_block (basic_block);
      91                 :            : static void rtl_delete_block (basic_block);
      92                 :            : static basic_block rtl_redirect_edge_and_branch_force (edge, basic_block);
      93                 :            : static edge rtl_redirect_edge_and_branch (edge, basic_block);
      94                 :            : static basic_block rtl_split_block (basic_block, void *);
      95                 :            : static void rtl_dump_bb (FILE *, basic_block, int, dump_flags_t);
      96                 :            : static int rtl_verify_flow_info_1 (void);
      97                 :            : static void rtl_make_forwarder_block (edge);
      98                 :            : 
      99                 :            : /* Return true if NOTE is not one of the ones that must be kept paired,
     100                 :            :    so that we may simply delete it.  */
     101                 :            : 
     102                 :            : static int
     103                 :    6405950 : can_delete_note_p (const rtx_note *note)
     104                 :            : {
     105                 :          0 :   switch (NOTE_KIND (note))
     106                 :            :     {
     107                 :            :     case NOTE_INSN_DELETED:
     108                 :            :     case NOTE_INSN_BASIC_BLOCK:
     109                 :            :     case NOTE_INSN_EPILOGUE_BEG:
     110                 :            :       return true;
     111                 :            : 
     112                 :          0 :     default:
     113                 :          0 :       return false;
     114                 :            :     }
     115                 :            : }
     116                 :            : 
     117                 :            : /* True if a given label can be deleted.  */
     118                 :            : 
     119                 :            : static int
     120                 :    4643600 : can_delete_label_p (const rtx_code_label *label)
     121                 :            : {
     122                 :    4643600 :   return (!LABEL_PRESERVE_P (label)
     123                 :            :           /* User declared labels must be preserved.  */
     124                 :    4641590 :           && LABEL_NAME (label) == 0
     125                 :    9280540 :           && !vec_safe_contains<rtx_insn *> (forced_labels,
     126                 :    4643600 :                                              const_cast<rtx_code_label *> (label)));
     127                 :            : }
     128                 :            : 
     129                 :            : /* Delete INSN by patching it out.  */
     130                 :            : 
     131                 :            : void
     132                 :   80404600 : delete_insn (rtx_insn *insn)
     133                 :            : {
     134                 :   80404600 :   rtx note;
     135                 :   80404600 :   bool really_delete = true;
     136                 :            : 
     137                 :   80404600 :   if (LABEL_P (insn))
     138                 :            :     {
     139                 :            :       /* Some labels can't be directly removed from the INSN chain, as they
     140                 :            :          might be references via variables, constant pool etc.
     141                 :            :          Convert them to the special NOTE_INSN_DELETED_LABEL note.  */
     142                 :    4643600 :       if (! can_delete_label_p (as_a <rtx_code_label *> (insn)))
     143                 :            :         {
     144                 :       6661 :           const char *name = LABEL_NAME (insn);
     145                 :       6661 :           basic_block bb = BLOCK_FOR_INSN (insn);
     146                 :       6661 :           rtx_insn *bb_note = NEXT_INSN (insn);
     147                 :            : 
     148                 :       6661 :           really_delete = false;
     149                 :       6661 :           PUT_CODE (insn, NOTE);
     150                 :       6661 :           NOTE_KIND (insn) = NOTE_INSN_DELETED_LABEL;
     151                 :       6661 :           NOTE_DELETED_LABEL_NAME (insn) = name;
     152                 :            : 
     153                 :            :           /* If the note following the label starts a basic block, and the
     154                 :            :              label is a member of the same basic block, interchange the two.  */
     155                 :       6661 :           if (bb_note != NULL_RTX
     156                 :       6630 :               && NOTE_INSN_BASIC_BLOCK_P (bb_note)
     157                 :        822 :               && bb != NULL
     158                 :       7483 :               && bb == BLOCK_FOR_INSN (bb_note))
     159                 :            :             {
     160                 :        798 :               reorder_insns_nobb (insn, insn, bb_note);
     161                 :        798 :               BB_HEAD (bb) = bb_note;
     162                 :        798 :               if (BB_END (bb) == bb_note)
     163                 :        160 :                 BB_END (bb) = insn;
     164                 :            :             }
     165                 :            :         }
     166                 :            : 
     167                 :    4643600 :       remove_node_from_insn_list (insn, &nonlocal_goto_handler_labels);
     168                 :            :     }
     169                 :            : 
     170                 :    4643600 :   if (really_delete)
     171                 :            :     {
     172                 :            :       /* If this insn has already been deleted, something is very wrong.  */
     173                 :   80397900 :       gcc_assert (!insn->deleted ());
     174                 :   80397900 :       if (INSN_P (insn))
     175                 :   58606500 :         df_insn_delete (insn);
     176                 :   80397900 :       remove_insn (insn);
     177                 :   80397900 :       insn->set_deleted ();
     178                 :            :     }
     179                 :            : 
     180                 :            :   /* If deleting a jump, decrement the use count of the label.  Deleting
     181                 :            :      the label itself should happen in the normal course of block merging.  */
     182                 :   80404600 :   if (JUMP_P (insn))
     183                 :            :     {
     184                 :    4115400 :       if (JUMP_LABEL (insn)
     185                 :    4115280 :           && LABEL_P (JUMP_LABEL (insn)))
     186                 :    4110930 :         LABEL_NUSES (JUMP_LABEL (insn))--;
     187                 :            : 
     188                 :            :       /* If there are more targets, remove them too.  */
     189                 :    4115400 :       while ((note
     190                 :    8230790 :               = find_reg_note (insn, REG_LABEL_TARGET, NULL_RTX)) != NULL_RTX
     191                 :    4115400 :              && LABEL_P (XEXP (note, 0)))
     192                 :            :         {
     193                 :          1 :           LABEL_NUSES (XEXP (note, 0))--;
     194                 :          1 :           remove_note (insn, note);
     195                 :            :         }
     196                 :            :     }
     197                 :            : 
     198                 :            :   /* Also if deleting any insn that references a label as an operand.  */
     199                 :       3840 :   while ((note = find_reg_note (insn, REG_LABEL_OPERAND, NULL_RTX)) != NULL_RTX
     200                 :   80408400 :          && LABEL_P (XEXP (note, 0)))
     201                 :            :     {
     202                 :       3840 :       LABEL_NUSES (XEXP (note, 0))--;
     203                 :       3840 :       remove_note (insn, note);
     204                 :            :     }
     205                 :            : 
     206                 :   80404600 :   if (rtx_jump_table_data *table = dyn_cast <rtx_jump_table_data *> (insn))
     207                 :            :     {
     208                 :          7 :       rtvec vec = table->get_labels ();
     209                 :          7 :       int len = GET_NUM_ELEM (vec);
     210                 :          7 :       int i;
     211                 :            : 
     212                 :        114 :       for (i = 0; i < len; i++)
     213                 :            :         {
     214                 :        107 :           rtx label = XEXP (RTVEC_ELT (vec, i), 0);
     215                 :            : 
     216                 :            :           /* When deleting code in bulk (e.g. removing many unreachable
     217                 :            :              blocks) we can delete a label that's a target of the vector
     218                 :            :              before deleting the vector itself.  */
     219                 :        107 :           if (!NOTE_P (label))
     220                 :        107 :             LABEL_NUSES (label)--;
     221                 :            :         }
     222                 :            :     }
     223                 :   80404600 : }
     224                 :            : 
     225                 :            : /* Like delete_insn but also purge dead edges from BB.
     226                 :            :    Return true if any edges are eliminated.  */
     227                 :            : 
     228                 :            : bool
     229                 :   10191700 : delete_insn_and_edges (rtx_insn *insn)
     230                 :            : {
     231                 :   10191700 :   bool purge = false;
     232                 :            : 
     233                 :   10191700 :   if (INSN_P (insn)
     234                 :   10191700 :       && BLOCK_FOR_INSN (insn)
     235                 :   20383400 :       && BB_END (BLOCK_FOR_INSN (insn)) == insn)
     236                 :            :     purge = true;
     237                 :   10191700 :   delete_insn (insn);
     238                 :   10191700 :   if (purge)
     239                 :     432452 :     return purge_dead_edges (BLOCK_FOR_INSN (insn));
     240                 :            :   return false;
     241                 :            : }
     242                 :            : 
     243                 :            : /* Unlink a chain of insns between START and FINISH, leaving notes
     244                 :            :    that must be paired.  If CLEAR_BB is true, we set bb field for
     245                 :            :    insns that cannot be removed to NULL.  */
     246                 :            : 
     247                 :            : void
     248                 :   10560500 : delete_insn_chain (rtx start, rtx_insn *finish, bool clear_bb)
     249                 :            : {
     250                 :            :   /* Unchain the insns one by one.  It would be quicker to delete all of these
     251                 :            :      with a single unchaining, rather than one at a time, but we need to keep
     252                 :            :      the NOTE's.  */
     253                 :   10560500 :   rtx_insn *current = finish;
     254                 :   17790100 :   while (1)
     255                 :            :     {
     256                 :   17790100 :       rtx_insn *prev = PREV_INSN (current);
     257                 :   17790100 :       if (NOTE_P (current) && !can_delete_note_p (as_a <rtx_note *> (current)))
     258                 :            :         ;
     259                 :            :       else
     260                 :   17787300 :         delete_insn (current);
     261                 :            : 
     262                 :   17790100 :       if (clear_bb && !current->deleted ())
     263                 :       8199 :         set_block_for_insn (current, NULL);
     264                 :            : 
     265                 :   17790100 :       if (current == start)
     266                 :            :         break;
     267                 :            :       current = prev;
     268                 :            :     }
     269                 :   10560500 : }
     270                 :            : 
     271                 :            : /* Create a new basic block consisting of the instructions between HEAD and END
     272                 :            :    inclusive.  This function is designed to allow fast BB construction - reuses
     273                 :            :    the note and basic block struct in BB_NOTE, if any and do not grow
     274                 :            :    BASIC_BLOCK chain and should be used directly only by CFG construction code.
     275                 :            :    END can be NULL in to create new empty basic block before HEAD.  Both END
     276                 :            :    and HEAD can be NULL to create basic block at the end of INSN chain.
     277                 :            :    AFTER is the basic block we should be put after.  */
     278                 :            : 
     279                 :            : basic_block
     280                 :    7834330 : create_basic_block_structure (rtx_insn *head, rtx_insn *end, rtx_note *bb_note,
     281                 :            :                               basic_block after)
     282                 :            : {
     283                 :    7834330 :   basic_block bb;
     284                 :            : 
     285                 :    7834330 :   if (bb_note
     286                 :          0 :       && (bb = NOTE_BASIC_BLOCK (bb_note)) != NULL
     287                 :    7834330 :       && bb->aux == NULL)
     288                 :            :     {
     289                 :            :       /* If we found an existing note, thread it back onto the chain.  */
     290                 :            : 
     291                 :          0 :       rtx_insn *after;
     292                 :            : 
     293                 :          0 :       if (LABEL_P (head))
     294                 :            :         after = head;
     295                 :            :       else
     296                 :            :         {
     297                 :          0 :           after = PREV_INSN (head);
     298                 :          0 :           head = bb_note;
     299                 :            :         }
     300                 :            : 
     301                 :          0 :       if (after != bb_note && NEXT_INSN (after) != bb_note)
     302                 :          0 :         reorder_insns_nobb (bb_note, bb_note, after);
     303                 :            :     }
     304                 :            :   else
     305                 :            :     {
     306                 :            :       /* Otherwise we must create a note and a basic block structure.  */
     307                 :            : 
     308                 :    7834330 :       bb = alloc_block ();
     309                 :            : 
     310                 :    7834330 :       init_rtl_bb_info (bb);
     311                 :    7834330 :       if (!head && !end)
     312                 :     220862 :         head = end = bb_note
     313                 :     220862 :           = emit_note_after (NOTE_INSN_BASIC_BLOCK, get_last_insn ());
     314                 :    7613470 :       else if (LABEL_P (head) && end)
     315                 :            :         {
     316                 :    1681270 :           bb_note = emit_note_after (NOTE_INSN_BASIC_BLOCK, head);
     317                 :    1681270 :           if (head == end)
     318                 :     546340 :             end = bb_note;
     319                 :            :         }
     320                 :            :       else
     321                 :            :         {
     322                 :    5932200 :           bb_note = emit_note_before (NOTE_INSN_BASIC_BLOCK, head);
     323                 :    5932200 :           head = bb_note;
     324                 :    5932200 :           if (!end)
     325                 :    3253010 :             end = head;
     326                 :            :         }
     327                 :            : 
     328                 :    7834330 :       NOTE_BASIC_BLOCK (bb_note) = bb;
     329                 :            :     }
     330                 :            : 
     331                 :            :   /* Always include the bb note in the block.  */
     332                 :    7834330 :   if (NEXT_INSN (end) == bb_note)
     333                 :          0 :     end = bb_note;
     334                 :            : 
     335                 :    7834330 :   BB_HEAD (bb) = head;
     336                 :    7834330 :   BB_END (bb) = end;
     337                 :    7834330 :   bb->index = last_basic_block_for_fn (cfun)++;
     338                 :    7834330 :   bb->flags = BB_NEW | BB_RTL;
     339                 :    7834330 :   link_block (bb, after);
     340                 :    7834330 :   SET_BASIC_BLOCK_FOR_FN (cfun, bb->index, bb);
     341                 :    7834330 :   df_bb_refs_record (bb->index, false);
     342                 :    7834330 :   update_bb_for_insn (bb);
     343                 :    7834330 :   BB_SET_PARTITION (bb, BB_UNPARTITIONED);
     344                 :            : 
     345                 :            :   /* Tag the block so that we know it has been used when considering
     346                 :            :      other basic block notes.  */
     347                 :    7834330 :   bb->aux = bb;
     348                 :            : 
     349                 :    7834330 :   return bb;
     350                 :            : }
     351                 :            : 
     352                 :            : /* Create new basic block consisting of instructions in between HEAD and END
     353                 :            :    and place it to the BB chain after block AFTER.  END can be NULL to
     354                 :            :    create a new empty basic block before HEAD.  Both END and HEAD can be
     355                 :            :    NULL to create basic block at the end of INSN chain.  */
     356                 :            : 
     357                 :            : static basic_block
     358                 :    7834330 : rtl_create_basic_block (void *headp, void *endp, basic_block after)
     359                 :            : {
     360                 :    7834330 :   rtx_insn *head = (rtx_insn *) headp;
     361                 :    7834330 :   rtx_insn *end = (rtx_insn *) endp;
     362                 :    7834330 :   basic_block bb;
     363                 :            : 
     364                 :            :   /* Grow the basic block array if needed.  */
     365                 :    7834330 :   if ((size_t) last_basic_block_for_fn (cfun)
     366                 :    7834330 :       >= basic_block_info_for_fn (cfun)->length ())
     367                 :            :     {
     368                 :      28660 :       size_t new_size =
     369                 :            :         (last_basic_block_for_fn (cfun)
     370                 :      28660 :          + (last_basic_block_for_fn (cfun) + 3) / 4);
     371                 :      28660 :       vec_safe_grow_cleared (basic_block_info_for_fn (cfun), new_size);
     372                 :            :     }
     373                 :            : 
     374                 :    7834330 :   n_basic_blocks_for_fn (cfun)++;
     375                 :            : 
     376                 :    7834330 :   bb = create_basic_block_structure (head, end, NULL, after);
     377                 :    7834330 :   bb->aux = NULL;
     378                 :    7834330 :   return bb;
     379                 :            : }
     380                 :            : 
     381                 :            : static basic_block
     382                 :    2367050 : cfg_layout_create_basic_block (void *head, void *end, basic_block after)
     383                 :            : {
     384                 :    2367050 :   basic_block newbb = rtl_create_basic_block (head, end, after);
     385                 :            : 
     386                 :    2367050 :   return newbb;
     387                 :            : }
     388                 :            : 
     389                 :            : /* Delete the insns in a (non-live) block.  We physically delete every
     390                 :            :    non-deleted-note insn, and update the flow graph appropriately.
     391                 :            : 
     392                 :            :    Return nonzero if we deleted an exception handler.  */
     393                 :            : 
     394                 :            : /* ??? Preserving all such notes strikes me as wrong.  It would be nice
     395                 :            :    to post-process the stream to remove empty blocks, loops, ranges, etc.  */
     396                 :            : 
     397                 :            : static void
     398                 :    4015410 : rtl_delete_block (basic_block b)
     399                 :            : {
     400                 :    4015410 :   rtx_insn *insn, *end;
     401                 :            : 
     402                 :            :   /* If the head of this block is a CODE_LABEL, then it might be the
     403                 :            :      label for an exception handler which can't be reached.  We need
     404                 :            :      to remove the label from the exception_handler_label list.  */
     405                 :    4015410 :   insn = BB_HEAD (b);
     406                 :            : 
     407                 :    4015410 :   end = get_last_bb_insn (b);
     408                 :            : 
     409                 :            :   /* Selectively delete the entire chain.  */
     410                 :    4015410 :   BB_HEAD (b) = NULL;
     411                 :    4015410 :   delete_insn_chain (insn, end, true);
     412                 :            : 
     413                 :            : 
     414                 :    4015410 :   if (dump_file)
     415                 :        684 :     fprintf (dump_file, "deleting block %d\n", b->index);
     416                 :    4015410 :   df_bb_delete (b->index);
     417                 :    4015410 : }
     418                 :            : 
     419                 :            : /* Records the basic block struct in BLOCK_FOR_INSN for every insn.  */
     420                 :            : 
     421                 :            : void
     422                 :     943048 : compute_bb_for_insn (void)
     423                 :            : {
     424                 :     943048 :   basic_block bb;
     425                 :            : 
     426                 :    9900170 :   FOR_EACH_BB_FN (bb, cfun)
     427                 :            :     {
     428                 :    8957120 :       rtx_insn *end = BB_END (bb);
     429                 :    8957120 :       rtx_insn *insn;
     430                 :            : 
     431                 :  102294000 :       for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn))
     432                 :            :         {
     433                 :  102294000 :           BLOCK_FOR_INSN (insn) = bb;
     434                 :  102294000 :           if (insn == end)
     435                 :            :             break;
     436                 :            :         }
     437                 :            :     }
     438                 :     943048 : }
     439                 :            : 
     440                 :            : /* Release the basic_block_for_insn array.  */
     441                 :            : 
     442                 :            : unsigned int
     443                 :    1886360 : free_bb_for_insn (void)
     444                 :            : {
     445                 :    1886360 :   rtx_insn *insn;
     446                 :  242737000 :   for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
     447                 :  120425000 :     if (!BARRIER_P (insn))
     448                 :  117385000 :       BLOCK_FOR_INSN (insn) = NULL;
     449                 :    1886360 :   return 0;
     450                 :            : }
     451                 :            : 
     452                 :            : namespace {
     453                 :            : 
     454                 :            : const pass_data pass_data_free_cfg =
     455                 :            : {
     456                 :            :   RTL_PASS, /* type */
     457                 :            :   "*free_cfg", /* name */
     458                 :            :   OPTGROUP_NONE, /* optinfo_flags */
     459                 :            :   TV_NONE, /* tv_id */
     460                 :            :   0, /* properties_required */
     461                 :            :   0, /* properties_provided */
     462                 :            :   PROP_cfg, /* properties_destroyed */
     463                 :            :   0, /* todo_flags_start */
     464                 :            :   0, /* todo_flags_finish */
     465                 :            : };
     466                 :            : 
     467                 :            : class pass_free_cfg : public rtl_opt_pass
     468                 :            : {
     469                 :            : public:
     470                 :     200540 :   pass_free_cfg (gcc::context *ctxt)
     471                 :     401080 :     : rtl_opt_pass (pass_data_free_cfg, ctxt)
     472                 :            :   {}
     473                 :            : 
     474                 :            :   /* opt_pass methods: */
     475                 :            :   virtual unsigned int execute (function *);
     476                 :            : 
     477                 :            : }; // class pass_free_cfg
     478                 :            : 
     479                 :            : unsigned int
     480                 :     942960 : pass_free_cfg::execute (function *)
     481                 :            : {
     482                 :            :   /* The resource.c machinery uses DF but the CFG isn't guaranteed to be
     483                 :            :      valid at that point so it would be too late to call df_analyze.  */
     484                 :     942960 :   if (DELAY_SLOTS && optimize > 0 && flag_delayed_branch)
     485                 :            :     {
     486                 :            :       df_note_add_problem ();
     487                 :            :       df_analyze ();
     488                 :            :     }
     489                 :            : 
     490                 :     942960 :   if (crtl->has_bb_partition)
     491                 :      48118 :     insert_section_boundary_note ();
     492                 :            : 
     493                 :     942960 :   free_bb_for_insn ();
     494                 :     942960 :   return 0;
     495                 :            : }
     496                 :            : 
     497                 :            : } // anon namespace
     498                 :            : 
     499                 :            : rtl_opt_pass *
     500                 :     200540 : make_pass_free_cfg (gcc::context *ctxt)
     501                 :            : {
     502                 :     200540 :   return new pass_free_cfg (ctxt);
     503                 :            : }
     504                 :            : 
     505                 :            : /* Return RTX to emit after when we want to emit code on the entry of function.  */
     506                 :            : rtx_insn *
     507                 :       5804 : entry_of_function (void)
     508                 :            : {
     509                 :       5804 :   return (n_basic_blocks_for_fn (cfun) > NUM_FIXED_BLOCKS ?
     510                 :       5804 :           BB_HEAD (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) : get_insns ());
     511                 :            : }
     512                 :            : 
     513                 :            : /* Emit INSN at the entry point of the function, ensuring that it is only
     514                 :            :    executed once per function.  */
     515                 :            : void
     516                 :          0 : emit_insn_at_entry (rtx insn)
     517                 :            : {
     518                 :          0 :   edge_iterator ei = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs);
     519                 :          0 :   edge e = ei_safe_edge (ei);
     520                 :          0 :   gcc_assert (e->flags & EDGE_FALLTHRU);
     521                 :            : 
     522                 :          0 :   insert_insn_on_edge (insn, e);
     523                 :          0 :   commit_edge_insertions ();
     524                 :          0 : }
     525                 :            : 
     526                 :            : /* Update BLOCK_FOR_INSN of insns between BEGIN and END
     527                 :            :    (or BARRIER if found) and notify df of the bb change.
     528                 :            :    The insn chain range is inclusive
     529                 :            :    (i.e. both BEGIN and END will be updated. */
     530                 :            : 
     531                 :            : static void
     532                 :   20619000 : update_bb_for_insn_chain (rtx_insn *begin, rtx_insn *end, basic_block bb)
     533                 :            : {
     534                 :   20619000 :   rtx_insn *insn;
     535                 :            : 
     536                 :   20619000 :   end = NEXT_INSN (end);
     537                 :  360989000 :   for (insn = begin; insn != end; insn = NEXT_INSN (insn))
     538                 :  170185000 :     if (!BARRIER_P (insn))
     539                 :  169075000 :       df_insn_change_bb (insn, bb);
     540                 :   20619000 : }
     541                 :            : 
     542                 :            : /* Update BLOCK_FOR_INSN of insns in BB to BB,
     543                 :            :    and notify df of the change.  */
     544                 :            : 
     545                 :            : void
     546                 :   18134100 : update_bb_for_insn (basic_block bb)
     547                 :            : {
     548                 :   18134100 :   update_bb_for_insn_chain (BB_HEAD (bb), BB_END (bb), bb);
     549                 :   18134100 : }
     550                 :            : 
     551                 :            : 
     552                 :            : /* Like active_insn_p, except keep the return value use or clobber around
     553                 :            :    even after reload.  */
     554                 :            : 
     555                 :            : static bool
     556                 :  186223000 : flow_active_insn_p (const rtx_insn *insn)
     557                 :            : {
     558                 :  186223000 :   if (active_insn_p (insn))
     559                 :            :     return true;
     560                 :            : 
     561                 :            :   /* A clobber of the function return value exists for buggy
     562                 :            :      programs that fail to return a value.  Its effect is to
     563                 :            :      keep the return value from being live across the entire
     564                 :            :      function.  If we allow it to be skipped, we introduce the
     565                 :            :      possibility for register lifetime confusion.
     566                 :            :      Similarly, keep a USE of the function return value, otherwise
     567                 :            :      the USE is dropped and we could fail to thread jump if USE
     568                 :            :      appears on some paths and not on others, see PR90257.  */
     569                 :  108982000 :   if ((GET_CODE (PATTERN (insn)) == CLOBBER
     570                 :  108915000 :        || GET_CODE (PATTERN (insn)) == USE)
     571                 :     414727 :       && REG_P (XEXP (PATTERN (insn), 0))
     572                 :  109392000 :       && REG_FUNCTION_VALUE_P (XEXP (PATTERN (insn), 0)))
     573                 :     355072 :     return true;
     574                 :            : 
     575                 :            :   return false;
     576                 :            : }
     577                 :            : 
     578                 :            : /* Return true if the block has no effect and only forwards control flow to
     579                 :            :    its single destination.  */
     580                 :            : 
     581                 :            : bool
     582                 :  194588000 : contains_no_active_insn_p (const_basic_block bb)
     583                 :            : {
     584                 :  194588000 :   rtx_insn *insn;
     585                 :            : 
     586                 :  194588000 :   if (bb == EXIT_BLOCK_PTR_FOR_FN (cfun)
     587                 :  194588000 :       || bb == ENTRY_BLOCK_PTR_FOR_FN (cfun)
     588                 :  194588000 :       || !single_succ_p (bb)
     589                 :  284039000 :       || (single_succ_edge (bb)->flags & EDGE_FAKE) != 0)
     590                 :            :     return false;
     591                 :            : 
     592                 :  571832000 :   for (insn = BB_HEAD (bb); insn != BB_END (bb); insn = NEXT_INSN (insn))
     593                 :  301590000 :     if (INSN_P (insn) && flow_active_insn_p (insn))
     594                 :            :       return false;
     595                 :            : 
     596                 :   28821600 :   return (!INSN_P (insn)
     597                 :   22410100 :           || (JUMP_P (insn) && simplejump_p (insn))
     598                 :   46463300 :           || !flow_active_insn_p (insn));
     599                 :            : }
     600                 :            : 
     601                 :            : /* Likewise, but protect loop latches, headers and preheaders.  */
     602                 :            : /* FIXME: Make this a cfg hook.  */
     603                 :            : 
     604                 :            : bool
     605                 :  194588000 : forwarder_block_p (const_basic_block bb)
     606                 :            : {
     607                 :  194588000 :   if (!contains_no_active_insn_p (bb))
     608                 :            :     return false;
     609                 :            : 
     610                 :            :   /* Protect loop latches, headers and preheaders.  */
     611                 :   11394900 :   if (current_loops)
     612                 :            :     {
     613                 :    5794260 :       basic_block dest;
     614                 :    5794260 :       if (bb->loop_father->header == bb)
     615                 :            :         return false;
     616                 :    5739700 :       dest = EDGE_SUCC (bb, 0)->dest;
     617                 :    5739700 :       if (dest->loop_father->header == dest)
     618                 :     798703 :         return false;
     619                 :            :     }
     620                 :            : 
     621                 :            :   return true;
     622                 :            : }
     623                 :            : 
     624                 :            : /* Return nonzero if we can reach target from src by falling through.  */
     625                 :            : /* FIXME: Make this a cfg hook, the result is only valid in cfgrtl mode.  */
     626                 :            : 
     627                 :            : bool
     628                 :   27073500 : can_fallthru (basic_block src, basic_block target)
     629                 :            : {
     630                 :   27073500 :   rtx_insn *insn = BB_END (src);
     631                 :   27073500 :   rtx_insn *insn2;
     632                 :   27073500 :   edge e;
     633                 :   27073500 :   edge_iterator ei;
     634                 :            : 
     635                 :   27073500 :   if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
     636                 :            :     return true;
     637                 :   26203100 :   if (src->next_bb != target)
     638                 :            :     return false;
     639                 :            : 
     640                 :            :   /* ??? Later we may add code to move jump tables offline.  */
     641                 :   10848800 :   if (tablejump_p (insn, NULL, NULL))
     642                 :            :     return false;
     643                 :            : 
     644                 :   29558700 :   FOR_EACH_EDGE (e, ei, src->succs)
     645                 :   18709800 :     if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)
     646                 :          0 :         && e->flags & EDGE_FALLTHRU)
     647                 :            :       return false;
     648                 :            : 
     649                 :   10848800 :   insn2 = BB_HEAD (target);
     650                 :   10848800 :   if (!active_insn_p (insn2))
     651                 :   10848800 :     insn2 = next_active_insn (insn2);
     652                 :            : 
     653                 :   10848800 :   return next_active_insn (insn) == insn2;
     654                 :            : }
     655                 :            : 
     656                 :            : /* Return nonzero if we could reach target from src by falling through,
     657                 :            :    if the target was made adjacent.  If we already have a fall-through
     658                 :            :    edge to the exit block, we can't do that.  */
     659                 :            : static bool
     660                 :    1458490 : could_fall_through (basic_block src, basic_block target)
     661                 :            : {
     662                 :    1458490 :   edge e;
     663                 :    1458490 :   edge_iterator ei;
     664                 :            : 
     665                 :    1458490 :   if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
     666                 :            :     return true;
     667                 :    4375460 :   FOR_EACH_EDGE (e, ei, src->succs)
     668                 :    2916970 :     if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)
     669                 :          0 :         && e->flags & EDGE_FALLTHRU)
     670                 :            :       return 0;
     671                 :            :   return true;
     672                 :            : }
     673                 :            : 
     674                 :            : /* Return the NOTE_INSN_BASIC_BLOCK of BB.  */
     675                 :            : rtx_note *
     676                 :     643514 : bb_note (basic_block bb)
     677                 :            : {
     678                 :     643514 :   rtx_insn *note;
     679                 :            : 
     680                 :     643514 :   note = BB_HEAD (bb);
     681                 :     643514 :   if (LABEL_P (note))
     682                 :     376866 :     note = NEXT_INSN (note);
     683                 :            : 
     684                 :     643514 :   gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note));
     685                 :     643514 :   return as_a <rtx_note *> (note);
     686                 :            : }
     687                 :            : 
     688                 :            : /* Return the INSN immediately following the NOTE_INSN_BASIC_BLOCK
     689                 :            :    note associated with the BLOCK.  */
     690                 :            : 
     691                 :            : static rtx_insn *
     692                 :       1897 : first_insn_after_basic_block_note (basic_block block)
     693                 :            : {
     694                 :       1897 :   rtx_insn *insn;
     695                 :            : 
     696                 :            :   /* Get the first instruction in the block.  */
     697                 :       1897 :   insn = BB_HEAD (block);
     698                 :            : 
     699                 :       1897 :   if (insn == NULL_RTX)
     700                 :            :     return NULL;
     701                 :       1897 :   if (LABEL_P (insn))
     702                 :       1897 :     insn = NEXT_INSN (insn);
     703                 :       1897 :   gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn));
     704                 :            : 
     705                 :       1897 :   return NEXT_INSN (insn);
     706                 :            : }
     707                 :            : 
     708                 :            : /* Creates a new basic block just after basic block BB by splitting
     709                 :            :    everything after specified instruction INSNP.  */
     710                 :            : 
     711                 :            : static basic_block
     712                 :    1760990 : rtl_split_block (basic_block bb, void *insnp)
     713                 :            : {
     714                 :    1760990 :   basic_block new_bb;
     715                 :    1760990 :   rtx_insn *insn = (rtx_insn *) insnp;
     716                 :    1760990 :   edge e;
     717                 :    1760990 :   edge_iterator ei;
     718                 :            : 
     719                 :    1760990 :   if (!insn)
     720                 :            :     {
     721                 :       1897 :       insn = first_insn_after_basic_block_note (bb);
     722                 :            : 
     723                 :       1897 :       if (insn)
     724                 :            :         {
     725                 :       1884 :           rtx_insn *next = insn;
     726                 :            : 
     727                 :       1884 :           insn = PREV_INSN (insn);
     728                 :            : 
     729                 :            :           /* If the block contains only debug insns, insn would have
     730                 :            :              been NULL in a non-debug compilation, and then we'd end
     731                 :            :              up emitting a DELETED note.  For -fcompare-debug
     732                 :            :              stability, emit the note too.  */
     733                 :       1884 :           if (insn != BB_END (bb)
     734                 :       1803 :               && DEBUG_INSN_P (next)
     735                 :        468 :               && DEBUG_INSN_P (BB_END (bb)))
     736                 :            :             {
     737                 :        158 :               while (next != BB_END (bb) && DEBUG_INSN_P (next))
     738                 :        133 :                 next = NEXT_INSN (next);
     739                 :            : 
     740                 :         25 :               if (next == BB_END (bb))
     741                 :         25 :                 emit_note_after (NOTE_INSN_DELETED, next);
     742                 :            :             }
     743                 :            :         }
     744                 :            :       else
     745                 :         13 :         insn = get_last_insn ();
     746                 :            :     }
     747                 :            : 
     748                 :            :   /* We probably should check type of the insn so that we do not create
     749                 :            :      inconsistent cfg.  It is checked in verify_flow_info anyway, so do not
     750                 :            :      bother.  */
     751                 :    1760990 :   if (insn == BB_END (bb))
     752                 :         94 :     emit_note_after (NOTE_INSN_DELETED, insn);
     753                 :            : 
     754                 :            :   /* Create the new basic block.  */
     755                 :    1760990 :   new_bb = create_basic_block (NEXT_INSN (insn), BB_END (bb), bb);
     756                 :    1760990 :   BB_COPY_PARTITION (new_bb, bb);
     757                 :    1760990 :   BB_END (bb) = insn;
     758                 :            : 
     759                 :            :   /* Redirect the outgoing edges.  */
     760                 :    1760990 :   new_bb->succs = bb->succs;
     761                 :    1760990 :   bb->succs = NULL;
     762                 :    4963710 :   FOR_EACH_EDGE (e, ei, new_bb->succs)
     763                 :    3202720 :     e->src = new_bb;
     764                 :            : 
     765                 :            :   /* The new block starts off being dirty.  */
     766                 :    1760990 :   df_set_bb_dirty (bb);
     767                 :    1760990 :   return new_bb;
     768                 :            : }
     769                 :            : 
     770                 :            : /* Return true if the single edge between blocks A and B is the only place
     771                 :            :    in RTL which holds some unique locus.  */
     772                 :            : 
     773                 :            : static bool
     774                 :     684821 : unique_locus_on_edge_between_p (basic_block a, basic_block b)
     775                 :            : {
     776                 :     684821 :   const location_t goto_locus = EDGE_SUCC (a, 0)->goto_locus;
     777                 :     684821 :   rtx_insn *insn, *end;
     778                 :            : 
     779                 :     684821 :   if (LOCATION_LOCUS (goto_locus) == UNKNOWN_LOCATION)
     780                 :            :     return false;
     781                 :            : 
     782                 :            :   /* First scan block A backward.  */
     783                 :     263753 :   insn = BB_END (a);
     784                 :     263753 :   end = PREV_INSN (BB_HEAD (a));
     785                 :     567149 :   while (insn != end && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn)))
     786                 :      34608 :     insn = PREV_INSN (insn);
     787                 :            : 
     788                 :     263753 :   if (insn != end && INSN_LOCATION (insn) == goto_locus)
     789                 :            :     return false;
     790                 :            : 
     791                 :            :   /* Then scan block B forward.  */
     792                 :      93539 :   insn = BB_HEAD (b);
     793                 :      93539 :   if (insn)
     794                 :            :     {
     795                 :      91362 :       end = NEXT_INSN (BB_END (b));
     796                 :      92144 :       while (insn != end && !NONDEBUG_INSN_P (insn))
     797                 :        782 :         insn = NEXT_INSN (insn);
     798                 :            : 
     799                 :      91282 :       if (insn != end && INSN_HAS_LOCATION (insn)
     800                 :     182526 :           && INSN_LOCATION (insn) == goto_locus)
     801                 :      86919 :         return false;
     802                 :            :     }
     803                 :            : 
     804                 :            :   return true;
     805                 :            : }
     806                 :            : 
     807                 :            : /* If the single edge between blocks A and B is the only place in RTL which
     808                 :            :    holds some unique locus, emit a nop with that locus between the blocks.  */
     809                 :            : 
     810                 :            : static void
     811                 :     684821 : emit_nop_for_unique_locus_between (basic_block a, basic_block b)
     812                 :            : {
     813                 :     684821 :   if (!unique_locus_on_edge_between_p (a, b))
     814                 :            :     return;
     815                 :            : 
     816                 :       6620 :   BB_END (a) = emit_insn_after_noloc (gen_nop (), BB_END (a), a);
     817                 :       6620 :   INSN_LOCATION (BB_END (a)) = EDGE_SUCC (a, 0)->goto_locus;
     818                 :            : }
     819                 :            : 
     820                 :            : /* Blocks A and B are to be merged into a single block A.  The insns
     821                 :            :    are already contiguous.  */
     822                 :            : 
     823                 :            : static void
     824                 :    2323260 : rtl_merge_blocks (basic_block a, basic_block b)
     825                 :            : {
     826                 :            :   /* If B is a forwarder block whose outgoing edge has no location, we'll
     827                 :            :      propagate the locus of the edge between A and B onto it.  */
     828                 :    2323260 :   const bool forward_edge_locus
     829                 :    2323260 :     = (b->flags & BB_FORWARDER_BLOCK) != 0
     830                 :    2323260 :       && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION;
     831                 :    2323260 :   rtx_insn *b_head = BB_HEAD (b), *b_end = BB_END (b), *a_end = BB_END (a);
     832                 :    2323260 :   rtx_insn *del_first = NULL, *del_last = NULL;
     833                 :    2323260 :   rtx_insn *b_debug_start = b_end, *b_debug_end = b_end;
     834                 :    2323260 :   int b_empty = 0;
     835                 :            : 
     836                 :    2323260 :   if (dump_file)
     837                 :        406 :     fprintf (dump_file, "Merging block %d into block %d...\n", b->index,
     838                 :            :              a->index);
     839                 :            : 
     840                 :    2745570 :   while (DEBUG_INSN_P (b_end))
     841                 :     422313 :     b_end = PREV_INSN (b_debug_start = b_end);
     842                 :            : 
     843                 :            :   /* If there was a CODE_LABEL beginning B, delete it.  */
     844                 :    2323260 :   if (LABEL_P (b_head))
     845                 :            :     {
     846                 :            :       /* Detect basic blocks with nothing but a label.  This can happen
     847                 :            :          in particular at the end of a function.  */
     848                 :    1037360 :       if (b_head == b_end)
     849                 :          0 :         b_empty = 1;
     850                 :            : 
     851                 :    1037360 :       del_first = del_last = b_head;
     852                 :    1037360 :       b_head = NEXT_INSN (b_head);
     853                 :            :     }
     854                 :            : 
     855                 :            :   /* Delete the basic block note and handle blocks containing just that
     856                 :            :      note.  */
     857                 :    2323260 :   if (NOTE_INSN_BASIC_BLOCK_P (b_head))
     858                 :            :     {
     859                 :    2323260 :       if (b_head == b_end)
     860                 :     357391 :         b_empty = 1;
     861                 :    2323260 :       if (! del_last)
     862                 :    1285900 :         del_first = b_head;
     863                 :            : 
     864                 :    2323260 :       del_last = b_head;
     865                 :    2323260 :       b_head = NEXT_INSN (b_head);
     866                 :            :     }
     867                 :            : 
     868                 :            :   /* If there was a jump out of A, delete it.  */
     869                 :    2323260 :   if (JUMP_P (a_end))
     870                 :            :     {
     871                 :      29593 :       rtx_insn *prev;
     872                 :            : 
     873                 :      29775 :       for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev))
     874                 :      29775 :         if (!NOTE_P (prev)
     875                 :        188 :             || NOTE_INSN_BASIC_BLOCK_P (prev)
     876                 :        182 :             || prev == BB_HEAD (a))
     877                 :            :           break;
     878                 :            : 
     879                 :            :       del_first = a_end;
     880                 :            : 
     881                 :            :       /* If this was a conditional jump, we need to also delete
     882                 :            :          the insn that set cc0.  */
     883                 :            :       if (HAVE_cc0 && only_sets_cc0_p (prev))
     884                 :            :         {
     885                 :            :           rtx_insn *tmp = prev;
     886                 :            : 
     887                 :            :           prev = prev_nonnote_insn (prev);
     888                 :            :           if (!prev)
     889                 :            :             prev = BB_HEAD (a);
     890                 :            :           del_first = tmp;
     891                 :            :         }
     892                 :            : 
     893                 :    2323260 :       a_end = PREV_INSN (del_first);
     894                 :            :     }
     895                 :    2293670 :   else if (BARRIER_P (NEXT_INSN (a_end)))
     896                 :          0 :     del_first = NEXT_INSN (a_end);
     897                 :            : 
     898                 :            :   /* Delete everything marked above as well as crap that might be
     899                 :            :      hanging out between the two blocks.  */
     900                 :    2323260 :   BB_END (a) = a_end;
     901                 :    2323260 :   BB_HEAD (b) = b_empty ? NULL : b_head;
     902                 :    2323260 :   delete_insn_chain (del_first, del_last, true);
     903                 :            : 
     904                 :            :   /* If not optimizing, preserve the locus of the single edge between
     905                 :            :      blocks A and B if necessary by emitting a nop.  */
     906                 :    2323260 :   if (!optimize
     907                 :     789126 :       && !forward_edge_locus
     908                 :    3007560 :       && !DECL_IGNORED_P (current_function_decl))
     909                 :            :     {
     910                 :     682209 :       emit_nop_for_unique_locus_between (a, b);
     911                 :     682209 :       a_end = BB_END (a);
     912                 :            :     }
     913                 :            : 
     914                 :            :   /* Reassociate the insns of B with A.  */
     915                 :    2323260 :   if (!b_empty)
     916                 :            :     {
     917                 :    1965870 :       update_bb_for_insn_chain (a_end, b_debug_end, a);
     918                 :            : 
     919                 :    1965870 :       BB_END (a) = b_debug_end;
     920                 :    1965870 :       BB_HEAD (b) = NULL;
     921                 :            :     }
     922                 :     357391 :   else if (b_end != b_debug_end)
     923                 :            :     {
     924                 :            :       /* Move any deleted labels and other notes between the end of A
     925                 :            :          and the debug insns that make up B after the debug insns,
     926                 :            :          bringing the debug insns into A while keeping the notes after
     927                 :            :          the end of A.  */
     928                 :      17624 :       if (NEXT_INSN (a_end) != b_debug_start)
     929                 :         27 :         reorder_insns_nobb (NEXT_INSN (a_end), PREV_INSN (b_debug_start),
     930                 :            :                             b_debug_end);
     931                 :      17624 :       update_bb_for_insn_chain (b_debug_start, b_debug_end, a);
     932                 :      17624 :       BB_END (a) = b_debug_end;
     933                 :            :     }
     934                 :            : 
     935                 :    2323260 :   df_bb_delete (b->index);
     936                 :            : 
     937                 :    2323260 :   if (forward_edge_locus)
     938                 :     369167 :     EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus;
     939                 :            : 
     940                 :    2323260 :   if (dump_file)
     941                 :        406 :     fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index);
     942                 :    2323260 : }
     943                 :            : 
     944                 :            : 
     945                 :            : /* Return true when block A and B can be merged.  */
     946                 :            : 
     947                 :            : static bool
     948                 :         52 : rtl_can_merge_blocks (basic_block a, basic_block b)
     949                 :            : {
     950                 :            :   /* If we are partitioning hot/cold basic blocks, we don't want to
     951                 :            :      mess up unconditional or indirect jumps that cross between hot
     952                 :            :      and cold sections.
     953                 :            : 
     954                 :            :      Basic block partitioning may result in some jumps that appear to
     955                 :            :      be optimizable (or blocks that appear to be mergeable), but which really
     956                 :            :      must be left untouched (they are required to make it safely across
     957                 :            :      partition boundaries).  See  the comments at the top of
     958                 :            :      bb-reorder.c:partition_hot_cold_basic_blocks for complete details.  */
     959                 :            : 
     960                 :         52 :   if (BB_PARTITION (a) != BB_PARTITION (b))
     961                 :            :     return false;
     962                 :            : 
     963                 :            :   /* Protect the loop latches.  */
     964                 :         52 :   if (current_loops && b->loop_father->latch == b)
     965                 :            :     return false;
     966                 :            : 
     967                 :            :   /* There must be exactly one edge in between the blocks.  */
     968                 :         52 :   return (single_succ_p (a)
     969                 :         48 :           && single_succ (a) == b
     970                 :         33 :           && single_pred_p (b)
     971                 :         33 :           && a != b
     972                 :            :           /* Must be simple edge.  */
     973                 :         33 :           && !(single_succ_edge (a)->flags & EDGE_COMPLEX)
     974                 :         33 :           && a->next_bb == b
     975                 :         33 :           && a != ENTRY_BLOCK_PTR_FOR_FN (cfun)
     976                 :         33 :           && b != EXIT_BLOCK_PTR_FOR_FN (cfun)
     977                 :            :           /* If the jump insn has side effects,
     978                 :            :              we can't kill the edge.  */
     979                 :         85 :           && (!JUMP_P (BB_END (a))
     980                 :          0 :               || (reload_completed
     981                 :          0 :                   ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a)))));
     982                 :            : }
     983                 :            : 
     984                 :            : /* Return the label in the head of basic block BLOCK.  Create one if it doesn't
     985                 :            :    exist.  */
     986                 :            : 
     987                 :            : rtx_code_label *
     988                 :   10482700 : block_label (basic_block block)
     989                 :            : {
     990                 :   10482700 :   if (block == EXIT_BLOCK_PTR_FOR_FN (cfun))
     991                 :            :     return NULL;
     992                 :            : 
     993                 :   10440500 :   if (!LABEL_P (BB_HEAD (block)))
     994                 :            :     {
     995                 :    3971690 :       BB_HEAD (block) = emit_label_before (gen_label_rtx (), BB_HEAD (block));
     996                 :            :     }
     997                 :            : 
     998                 :   10440500 :   return as_a <rtx_code_label *> (BB_HEAD (block));
     999                 :            : }
    1000                 :            : 
    1001                 :            : /* Remove all barriers from BB_FOOTER of a BB.  */
    1002                 :            : 
    1003                 :            : static void
    1004                 :    2276470 : remove_barriers_from_footer (basic_block bb)
    1005                 :            : {
    1006                 :    2276470 :   rtx_insn *insn = BB_FOOTER (bb);
    1007                 :            : 
    1008                 :            :   /* Remove barriers but keep jumptables.  */
    1009                 :    4402550 :   while (insn)
    1010                 :            :     {
    1011                 :    2126080 :       if (BARRIER_P (insn))
    1012                 :            :         {
    1013                 :    2126060 :           if (PREV_INSN (insn))
    1014                 :         25 :             SET_NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn);
    1015                 :            :           else
    1016                 :    2126040 :             BB_FOOTER (bb) = NEXT_INSN (insn);
    1017                 :    2126060 :           if (NEXT_INSN (insn))
    1018                 :       8051 :             SET_PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn);
    1019                 :            :         }
    1020                 :    2126080 :       if (LABEL_P (insn))
    1021                 :            :         return;
    1022                 :    2126080 :       insn = NEXT_INSN (insn);
    1023                 :            :     }
    1024                 :            : }
    1025                 :            : 
    1026                 :            : /* Attempt to perform edge redirection by replacing possibly complex jump
    1027                 :            :    instruction by unconditional jump or removing jump completely.  This can
    1028                 :            :    apply only if all edges now point to the same block.  The parameters and
    1029                 :            :    return values are equivalent to redirect_edge_and_branch.  */
    1030                 :            : 
    1031                 :            : edge
    1032                 :   28661000 : try_redirect_by_replacing_jump (edge e, basic_block target, bool in_cfglayout)
    1033                 :            : {
    1034                 :   28661000 :   basic_block src = e->src;
    1035                 :   28661000 :   rtx_insn *insn = BB_END (src), *kill_from;
    1036                 :   28661000 :   rtx set;
    1037                 :   28661000 :   int fallthru = 0;
    1038                 :            : 
    1039                 :            :   /* If we are partitioning hot/cold basic blocks, we don't want to
    1040                 :            :      mess up unconditional or indirect jumps that cross between hot
    1041                 :            :      and cold sections.
    1042                 :            : 
    1043                 :            :      Basic block partitioning may result in some jumps that appear to
    1044                 :            :      be optimizable (or blocks that appear to be mergeable), but which really
    1045                 :            :      must be left untouched (they are required to make it safely across
    1046                 :            :      partition boundaries).  See  the comments at the top of
    1047                 :            :      bb-reorder.c:partition_hot_cold_basic_blocks for complete details.  */
    1048                 :            : 
    1049                 :   28661000 :   if (BB_PARTITION (src) != BB_PARTITION (target))
    1050                 :            :     return NULL;
    1051                 :            : 
    1052                 :            :   /* We can replace or remove a complex jump only when we have exactly
    1053                 :            :      two edges.  Also, if we have exactly one outgoing edge, we can
    1054                 :            :      redirect that.  */
    1055                 :   28657900 :   if (EDGE_COUNT (src->succs) >= 3
    1056                 :            :       /* Verify that all targets will be TARGET.  Specifically, the
    1057                 :            :          edge that is not E must also go to TARGET.  */
    1058                 :   28657900 :       || (EDGE_COUNT (src->succs) == 2
    1059                 :   10759800 :           && EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target))
    1060                 :            :     return NULL;
    1061                 :            : 
    1062                 :   17960400 :   if (!onlyjump_p (insn))
    1063                 :            :     return NULL;
    1064                 :   17209800 :   if ((!optimize || reload_completed) && tablejump_p (insn, NULL, NULL))
    1065                 :            :     return NULL;
    1066                 :            : 
    1067                 :            :   /* Avoid removing branch with side effects.  */
    1068                 :   17209200 :   set = single_set (insn);
    1069                 :   17209200 :   if (!set || side_effects_p (set))
    1070                 :          0 :     return NULL;
    1071                 :            : 
    1072                 :            :   /* In case we zap a conditional jump, we'll need to kill
    1073                 :            :      the cc0 setter too.  */
    1074                 :   17209200 :   kill_from = insn;
    1075                 :   17209200 :   if (HAVE_cc0 && reg_mentioned_p (cc0_rtx, PATTERN (insn))
    1076                 :            :       && only_sets_cc0_p (PREV_INSN (insn)))
    1077                 :            :     kill_from = PREV_INSN (insn);
    1078                 :            : 
    1079                 :            :   /* See if we can create the fallthru edge.  */
    1080                 :   17209200 :   if (in_cfglayout || can_fallthru (src, target))
    1081                 :            :     {
    1082                 :    2796040 :       if (dump_file)
    1083                 :        681 :         fprintf (dump_file, "Removing jump %i.\n", INSN_UID (insn));
    1084                 :    2796040 :       fallthru = 1;
    1085                 :            : 
    1086                 :            :       /* Selectively unlink whole insn chain.  */
    1087                 :    2796040 :       if (in_cfglayout)
    1088                 :            :         {
    1089                 :    2276470 :           delete_insn_chain (kill_from, BB_END (src), false);
    1090                 :    2276470 :           remove_barriers_from_footer (src);
    1091                 :            :         }
    1092                 :            :       else
    1093                 :     519573 :         delete_insn_chain (kill_from, PREV_INSN (BB_HEAD (target)),
    1094                 :            :                            false);
    1095                 :            :     }
    1096                 :            : 
    1097                 :            :   /* If this already is simplejump, redirect it.  */
    1098                 :   14413200 :   else if (simplejump_p (insn))
    1099                 :            :     {
    1100                 :   14411900 :       if (e->dest == target)
    1101                 :            :         return NULL;
    1102                 :     346295 :       if (dump_file)
    1103                 :         35 :         fprintf (dump_file, "Redirecting jump %i from %i to %i.\n",
    1104                 :         35 :                  INSN_UID (insn), e->dest->index, target->index);
    1105                 :     346295 :       if (!redirect_jump (as_a <rtx_jump_insn *> (insn),
    1106                 :     346295 :                           block_label (target), 0))
    1107                 :            :         {
    1108                 :          0 :           gcc_assert (target == EXIT_BLOCK_PTR_FOR_FN (cfun));
    1109                 :            :           return NULL;
    1110                 :            :         }
    1111                 :            :     }
    1112                 :            : 
    1113                 :            :   /* Cannot do anything for target exit block.  */
    1114                 :       1311 :   else if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
    1115                 :            :     return NULL;
    1116                 :            : 
    1117                 :            :   /* Or replace possibly complicated jump insn by simple jump insn.  */
    1118                 :            :   else
    1119                 :            :     {
    1120                 :       1311 :       rtx_code_label *target_label = block_label (target);
    1121                 :       1311 :       rtx_insn *barrier;
    1122                 :       1311 :       rtx_insn *label;
    1123                 :       1311 :       rtx_jump_table_data *table;
    1124                 :            : 
    1125                 :       1311 :       emit_jump_insn_after_noloc (targetm.gen_jump (target_label), insn);
    1126                 :       1311 :       JUMP_LABEL (BB_END (src)) = target_label;
    1127                 :       1311 :       LABEL_NUSES (target_label)++;
    1128                 :       1311 :       if (dump_file)
    1129                 :          0 :         fprintf (dump_file, "Replacing insn %i by jump %i\n",
    1130                 :          0 :                  INSN_UID (insn), INSN_UID (BB_END (src)));
    1131                 :            : 
    1132                 :            : 
    1133                 :       1311 :       delete_insn_chain (kill_from, insn, false);
    1134                 :            : 
    1135                 :            :       /* Recognize a tablejump that we are converting to a
    1136                 :            :          simple jump and remove its associated CODE_LABEL
    1137                 :            :          and ADDR_VEC or ADDR_DIFF_VEC.  */
    1138                 :       1311 :       if (tablejump_p (insn, &label, &table))
    1139                 :          5 :         delete_insn_chain (label, table, false);
    1140                 :            : 
    1141                 :       1311 :       barrier = next_nonnote_nondebug_insn (BB_END (src));
    1142                 :       1311 :       if (!barrier || !BARRIER_P (barrier))
    1143                 :       1229 :         emit_barrier_after (BB_END (src));
    1144                 :            :       else
    1145                 :            :         {
    1146                 :         82 :           if (barrier != NEXT_INSN (BB_END (src)))
    1147                 :            :             {
    1148                 :            :               /* Move the jump before barrier so that the notes
    1149                 :            :                  which originally were or were created before jump table are
    1150                 :            :                  inside the basic block.  */
    1151                 :          0 :               rtx_insn *new_insn = BB_END (src);
    1152                 :            : 
    1153                 :          0 :               update_bb_for_insn_chain (NEXT_INSN (BB_END (src)),
    1154                 :            :                                         PREV_INSN (barrier), src);
    1155                 :            : 
    1156                 :          0 :               SET_NEXT_INSN (PREV_INSN (new_insn)) = NEXT_INSN (new_insn);
    1157                 :          0 :               SET_PREV_INSN (NEXT_INSN (new_insn)) = PREV_INSN (new_insn);
    1158                 :            : 
    1159                 :          0 :               SET_NEXT_INSN (new_insn) = barrier;
    1160                 :          0 :               SET_NEXT_INSN (PREV_INSN (barrier)) = new_insn;
    1161                 :            : 
    1162                 :          0 :               SET_PREV_INSN (new_insn) = PREV_INSN (barrier);
    1163                 :          0 :               SET_PREV_INSN (barrier) = new_insn;
    1164                 :            :             }
    1165                 :            :         }
    1166                 :            :     }
    1167                 :            : 
    1168                 :            :   /* Keep only one edge out and set proper flags.  */
    1169                 :    3143640 :   if (!single_succ_p (src))
    1170                 :      69814 :     remove_edge (e);
    1171                 :    3143640 :   gcc_assert (single_succ_p (src));
    1172                 :            : 
    1173                 :    3143640 :   e = single_succ_edge (src);
    1174                 :    3143640 :   if (fallthru)
    1175                 :    2796040 :     e->flags = EDGE_FALLTHRU;
    1176                 :            :   else
    1177                 :     347606 :     e->flags = 0;
    1178                 :            : 
    1179                 :    3143640 :   e->probability = profile_probability::always ();
    1180                 :            : 
    1181                 :    3143640 :   if (e->dest != target)
    1182                 :     490816 :     redirect_edge_succ (e, target);
    1183                 :            :   return e;
    1184                 :            : }
    1185                 :            : 
    1186                 :            : /* Subroutine of redirect_branch_edge that tries to patch the jump
    1187                 :            :    instruction INSN so that it reaches block NEW.  Do this
    1188                 :            :    only when it originally reached block OLD.  Return true if this
    1189                 :            :    worked or the original target wasn't OLD, return false if redirection
    1190                 :            :    doesn't work.  */
    1191                 :            : 
    1192                 :            : static bool
    1193                 :    4024070 : patch_jump_insn (rtx_insn *insn, rtx_insn *old_label, basic_block new_bb)
    1194                 :            : {
    1195                 :    4024070 :   rtx_jump_table_data *table;
    1196                 :    4024070 :   rtx tmp;
    1197                 :            :   /* Recognize a tablejump and adjust all matching cases.  */
    1198                 :    4024070 :   if (tablejump_p (insn, NULL, &table))
    1199                 :            :     {
    1200                 :       4642 :       rtvec vec;
    1201                 :       4642 :       int j;
    1202                 :       4642 :       rtx_code_label *new_label = block_label (new_bb);
    1203                 :            : 
    1204                 :       4642 :       if (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun))
    1205                 :            :         return false;
    1206                 :       4642 :       vec = table->get_labels ();
    1207                 :            : 
    1208                 :     137457 :       for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j)
    1209                 :     132815 :         if (XEXP (RTVEC_ELT (vec, j), 0) == old_label)
    1210                 :            :           {
    1211                 :      30592 :             RTVEC_ELT (vec, j) = gen_rtx_LABEL_REF (Pmode, new_label);
    1212                 :      22662 :             --LABEL_NUSES (old_label);
    1213                 :      22662 :             ++LABEL_NUSES (new_label);
    1214                 :            :           }
    1215                 :            : 
    1216                 :            :       /* Handle casesi dispatch insns.  */
    1217                 :       4642 :       if ((tmp = tablejump_casesi_pattern (insn)) != NULL_RTX
    1218                 :       4642 :           && label_ref_label (XEXP (SET_SRC (tmp), 2)) == old_label)
    1219                 :            :         {
    1220                 :          0 :           XEXP (SET_SRC (tmp), 2) = gen_rtx_LABEL_REF (Pmode,
    1221                 :            :                                                        new_label);
    1222                 :          0 :           --LABEL_NUSES (old_label);
    1223                 :          0 :           ++LABEL_NUSES (new_label);
    1224                 :            :         }
    1225                 :            :     }
    1226                 :    4019420 :   else if ((tmp = extract_asm_operands (PATTERN (insn))) != NULL)
    1227                 :            :     {
    1228                 :        155 :       int i, n = ASM_OPERANDS_LABEL_LENGTH (tmp);
    1229                 :        155 :       rtx note;
    1230                 :            : 
    1231                 :        155 :       if (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun))
    1232                 :            :         return false;
    1233                 :        155 :       rtx_code_label *new_label = block_label (new_bb);
    1234                 :            : 
    1235                 :        362 :       for (i = 0; i < n; ++i)
    1236                 :            :         {
    1237                 :        207 :           rtx old_ref = ASM_OPERANDS_LABEL (tmp, i);
    1238                 :        207 :           gcc_assert (GET_CODE (old_ref) == LABEL_REF);
    1239                 :        207 :           if (XEXP (old_ref, 0) == old_label)
    1240                 :            :             {
    1241                 :        138 :               ASM_OPERANDS_LABEL (tmp, i)
    1242                 :        138 :                 = gen_rtx_LABEL_REF (Pmode, new_label);
    1243                 :        138 :               --LABEL_NUSES (old_label);
    1244                 :        138 :               ++LABEL_NUSES (new_label);
    1245                 :            :             }
    1246                 :            :         }
    1247                 :            : 
    1248                 :        155 :       if (JUMP_LABEL (insn) == old_label)
    1249                 :            :         {
    1250                 :        102 :           JUMP_LABEL (insn) = new_label;
    1251                 :        102 :           note = find_reg_note (insn, REG_LABEL_TARGET, new_label);
    1252                 :        102 :           if (note)
    1253                 :          0 :             remove_note (insn, note);
    1254                 :            :         }
    1255                 :            :       else
    1256                 :            :         {
    1257                 :         53 :           note = find_reg_note (insn, REG_LABEL_TARGET, old_label);
    1258                 :         53 :           if (note)
    1259                 :         34 :             remove_note (insn, note);
    1260                 :         53 :           if (JUMP_LABEL (insn) != new_label
    1261                 :         53 :               && !find_reg_note (insn, REG_LABEL_TARGET, new_label))
    1262                 :         45 :             add_reg_note (insn, REG_LABEL_TARGET, new_label);
    1263                 :            :         }
    1264                 :        310 :       while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label))
    1265                 :        155 :              != NULL_RTX)
    1266                 :          0 :         XEXP (note, 0) = new_label;
    1267                 :            :     }
    1268                 :            :   else
    1269                 :            :     {
    1270                 :            :       /* ?? We may play the games with moving the named labels from
    1271                 :            :          one basic block to the other in case only one computed_jump is
    1272                 :            :          available.  */
    1273                 :    4019270 :       if (computed_jump_p (insn)
    1274                 :            :           /* A return instruction can't be redirected.  */
    1275                 :    4019270 :           || returnjump_p (insn))
    1276                 :          0 :         return false;
    1277                 :            : 
    1278                 :    4019270 :       if (!currently_expanding_to_rtl || JUMP_LABEL (insn) == old_label)
    1279                 :            :         {
    1280                 :            :           /* If the insn doesn't go where we think, we're confused.  */
    1281                 :    4005430 :           gcc_assert (JUMP_LABEL (insn) == old_label);
    1282                 :            : 
    1283                 :            :           /* If the substitution doesn't succeed, die.  This can happen
    1284                 :            :              if the back end emitted unrecognizable instructions or if
    1285                 :            :              target is exit block on some arches.  Or for crossing
    1286                 :            :              jumps.  */
    1287                 :    4005430 :           if (!redirect_jump (as_a <rtx_jump_insn *> (insn),
    1288                 :    4005430 :                               block_label (new_bb), 0))
    1289                 :            :             {
    1290                 :          0 :               gcc_assert (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)
    1291                 :            :                           || CROSSING_JUMP_P (insn));
    1292                 :            :               return false;
    1293                 :            :             }
    1294                 :            :         }
    1295                 :            :     }
    1296                 :            :   return true;
    1297                 :            : }
    1298                 :            : 
    1299                 :            : 
    1300                 :            : /* Redirect edge representing branch of (un)conditional jump or tablejump,
    1301                 :            :    NULL on failure  */
    1302                 :            : static edge
    1303                 :    8700870 : redirect_branch_edge (edge e, basic_block target)
    1304                 :            : {
    1305                 :    8700870 :   rtx_insn *old_label = BB_HEAD (e->dest);
    1306                 :    8700870 :   basic_block src = e->src;
    1307                 :    8700870 :   rtx_insn *insn = BB_END (src);
    1308                 :            : 
    1309                 :            :   /* We can only redirect non-fallthru edges of jump insn.  */
    1310                 :    8700870 :   if (e->flags & EDGE_FALLTHRU)
    1311                 :            :     return NULL;
    1312                 :    4005630 :   else if (!JUMP_P (insn) && !currently_expanding_to_rtl)
    1313                 :            :     return NULL;
    1314                 :            : 
    1315                 :    4005630 :   if (!currently_expanding_to_rtl)
    1316                 :            :     {
    1317                 :    3730390 :       if (!patch_jump_insn (as_a <rtx_jump_insn *> (insn), old_label, target))
    1318                 :            :         return NULL;
    1319                 :            :     }
    1320                 :            :   else
    1321                 :            :     /* When expanding this BB might actually contain multiple
    1322                 :            :        jumps (i.e. not yet split by find_many_sub_basic_blocks).
    1323                 :            :        Redirect all of those that match our label.  */
    1324                 :    7629260 :     FOR_BB_INSNS (src, insn)
    1325                 :    3677010 :       if (JUMP_P (insn) && !patch_jump_insn (as_a <rtx_jump_insn *> (insn),
    1326                 :            :                                              old_label, target))
    1327                 :            :         return NULL;
    1328                 :            : 
    1329                 :    4005630 :   if (dump_file)
    1330                 :        890 :     fprintf (dump_file, "Edge %i->%i redirected to %i\n",
    1331                 :        890 :              e->src->index, e->dest->index, target->index);
    1332                 :            : 
    1333                 :    4005630 :   if (e->dest != target)
    1334                 :    4005630 :     e = redirect_edge_succ_nodup (e, target);
    1335                 :            : 
    1336                 :            :   return e;
    1337                 :            : }
    1338                 :            : 
    1339                 :            : /* Called when edge E has been redirected to a new destination,
    1340                 :            :    in order to update the region crossing flag on the edge and
    1341                 :            :    jump.  */
    1342                 :            : 
    1343                 :            : static void
    1344                 :   11031700 : fixup_partition_crossing (edge e)
    1345                 :            : {
    1346                 :   11031700 :   if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun) || e->dest
    1347                 :   11031700 :       == EXIT_BLOCK_PTR_FOR_FN (cfun))
    1348                 :            :     return;
    1349                 :            :   /* If we redirected an existing edge, it may already be marked
    1350                 :            :      crossing, even though the new src is missing a reg crossing note.
    1351                 :            :      But make sure reg crossing note doesn't already exist before
    1352                 :            :      inserting.  */
    1353                 :   11031700 :   if (BB_PARTITION (e->src) != BB_PARTITION (e->dest))
    1354                 :            :     {
    1355                 :      48132 :       e->flags |= EDGE_CROSSING;
    1356                 :      48132 :       if (JUMP_P (BB_END (e->src)))
    1357                 :      48132 :         CROSSING_JUMP_P (BB_END (e->src)) = 1;
    1358                 :            :     }
    1359                 :   10983600 :   else if (BB_PARTITION (e->src) == BB_PARTITION (e->dest))
    1360                 :            :     {
    1361                 :   10983600 :       e->flags &= ~EDGE_CROSSING;
    1362                 :            :       /* Remove the section crossing note from jump at end of
    1363                 :            :          src if it exists, and if no other successors are
    1364                 :            :          still crossing.  */
    1365                 :   10983600 :       if (JUMP_P (BB_END (e->src)) && CROSSING_JUMP_P (BB_END (e->src)))
    1366                 :            :         {
    1367                 :     132155 :           bool has_crossing_succ = false;
    1368                 :     132155 :           edge e2;
    1369                 :     132155 :           edge_iterator ei;
    1370                 :     227650 :           FOR_EACH_EDGE (e2, ei, e->src->succs)
    1371                 :            :             {
    1372                 :     184495 :               has_crossing_succ |= (e2->flags & EDGE_CROSSING);
    1373                 :     184495 :               if (has_crossing_succ)
    1374                 :            :                 break;
    1375                 :            :             }
    1376                 :     132155 :           if (!has_crossing_succ)
    1377                 :      43155 :             CROSSING_JUMP_P (BB_END (e->src)) = 0;
    1378                 :            :         }
    1379                 :            :     }
    1380                 :            : }
    1381                 :            : 
    1382                 :            : /* Called when block BB has been reassigned to the cold partition,
    1383                 :            :    because it is now dominated by another cold block,
    1384                 :            :    to ensure that the region crossing attributes are updated.  */
    1385                 :            : 
    1386                 :            : static void
    1387                 :         18 : fixup_new_cold_bb (basic_block bb)
    1388                 :            : {
    1389                 :         18 :   edge e;
    1390                 :         18 :   edge_iterator ei;
    1391                 :            : 
    1392                 :            :   /* This is called when a hot bb is found to now be dominated
    1393                 :            :      by a cold bb and therefore needs to become cold. Therefore,
    1394                 :            :      its preds will no longer be region crossing. Any non-dominating
    1395                 :            :      preds that were previously hot would also have become cold
    1396                 :            :      in the caller for the same region. Any preds that were previously
    1397                 :            :      region-crossing will be adjusted in fixup_partition_crossing.  */
    1398                 :         39 :   FOR_EACH_EDGE (e, ei, bb->preds)
    1399                 :            :     {
    1400                 :         21 :       fixup_partition_crossing (e);
    1401                 :            :     }
    1402                 :            : 
    1403                 :            :   /* Possibly need to make bb's successor edges region crossing,
    1404                 :            :      or remove stale region crossing.  */
    1405                 :         38 :   FOR_EACH_EDGE (e, ei, bb->succs)
    1406                 :            :     {
    1407                 :            :       /* We can't have fall-through edges across partition boundaries.
    1408                 :            :          Note that force_nonfallthru will do any necessary partition
    1409                 :            :          boundary fixup by calling fixup_partition_crossing itself.  */
    1410                 :         20 :       if ((e->flags & EDGE_FALLTHRU)
    1411                 :         13 :           && BB_PARTITION (bb) != BB_PARTITION (e->dest)
    1412                 :         13 :           && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
    1413                 :          0 :         force_nonfallthru (e);
    1414                 :            :       else
    1415                 :         20 :         fixup_partition_crossing (e);
    1416                 :            :     }
    1417                 :         18 : }
    1418                 :            : 
    1419                 :            : /* Attempt to change code to redirect edge E to TARGET.  Don't do that on
    1420                 :            :    expense of adding new instructions or reordering basic blocks.
    1421                 :            : 
    1422                 :            :    Function can be also called with edge destination equivalent to the TARGET.
    1423                 :            :    Then it should try the simplifications and do nothing if none is possible.
    1424                 :            : 
    1425                 :            :    Return edge representing the branch if transformation succeeded.  Return NULL
    1426                 :            :    on failure.
    1427                 :            :    We still return NULL in case E already destinated TARGET and we didn't
    1428                 :            :    managed to simplify instruction stream.  */
    1429                 :            : 
    1430                 :            : static edge
    1431                 :    6208330 : rtl_redirect_edge_and_branch (edge e, basic_block target)
    1432                 :            : {
    1433                 :    6208330 :   edge ret;
    1434                 :    6208330 :   basic_block src = e->src;
    1435                 :    6208330 :   basic_block dest = e->dest;
    1436                 :            : 
    1437                 :    6208330 :   if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
    1438                 :            :     return NULL;
    1439                 :            : 
    1440                 :    6208330 :   if (dest == target)
    1441                 :            :     return e;
    1442                 :            : 
    1443                 :    6208320 :   if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL)
    1444                 :            :     {
    1445                 :     405464 :       df_set_bb_dirty (src);
    1446                 :     405464 :       fixup_partition_crossing (ret);
    1447                 :     405464 :       return ret;
    1448                 :            :     }
    1449                 :            : 
    1450                 :    5802860 :   ret = redirect_branch_edge (e, target);
    1451                 :    5802860 :   if (!ret)
    1452                 :            :     return NULL;
    1453                 :            : 
    1454                 :    1107620 :   df_set_bb_dirty (src);
    1455                 :    1107620 :   fixup_partition_crossing (ret);
    1456                 :    1107620 :   return ret;
    1457                 :            : }
    1458                 :            : 
    1459                 :            : /* Emit a barrier after BB, into the footer if we are in CFGLAYOUT mode.  */
    1460                 :            : 
    1461                 :            : void
    1462                 :    3334800 : emit_barrier_after_bb (basic_block bb)
    1463                 :            : {
    1464                 :    3334800 :   rtx_barrier *barrier = emit_barrier_after (BB_END (bb));
    1465                 :    3334800 :   gcc_assert (current_ir_type () == IR_RTL_CFGRTL
    1466                 :            :               || current_ir_type () == IR_RTL_CFGLAYOUT);
    1467                 :    3334800 :   if (current_ir_type () == IR_RTL_CFGLAYOUT)
    1468                 :            :     {
    1469                 :      46973 :       rtx_insn *insn = unlink_insn_chain (barrier, barrier);
    1470                 :            : 
    1471                 :      46973 :       if (BB_FOOTER (bb))
    1472                 :            :         {
    1473                 :            :           rtx_insn *footer_tail = BB_FOOTER (bb);
    1474                 :            : 
    1475                 :       1843 :           while (NEXT_INSN (footer_tail))
    1476                 :       1843 :             footer_tail = NEXT_INSN (footer_tail);
    1477                 :       1843 :           if (!BARRIER_P (footer_tail))
    1478                 :            :             {
    1479                 :          1 :               SET_NEXT_INSN (footer_tail) = insn;
    1480                 :          1 :               SET_PREV_INSN (insn) = footer_tail;
    1481                 :            :             }
    1482                 :            :         }
    1483                 :            :       else
    1484                 :      45130 :         BB_FOOTER (bb) = insn;
    1485                 :            :     }
    1486                 :    3334800 : }
    1487                 :            : 
    1488                 :            : /* Like force_nonfallthru below, but additionally performs redirection
    1489                 :            :    Used by redirect_edge_and_branch_force.  JUMP_LABEL is used only
    1490                 :            :    when redirecting to the EXIT_BLOCK, it is either ret_rtx or
    1491                 :            :    simple_return_rtx, indicating which kind of returnjump to create.
    1492                 :            :    It should be NULL otherwise.  */
    1493                 :            : 
    1494                 :            : basic_block
    1495                 :    3258890 : force_nonfallthru_and_redirect (edge e, basic_block target, rtx jump_label)
    1496                 :            : {
    1497                 :    3258890 :   basic_block jump_block, new_bb = NULL, src = e->src;
    1498                 :    3258890 :   rtx note;
    1499                 :    3258890 :   edge new_edge;
    1500                 :    3258890 :   int abnormal_edge_flags = 0;
    1501                 :    3258890 :   bool asm_goto_edge = false;
    1502                 :    3258890 :   int loc;
    1503                 :            : 
    1504                 :            :   /* In the case the last instruction is conditional jump to the next
    1505                 :            :      instruction, first redirect the jump itself and then continue
    1506                 :            :      by creating a basic block afterwards to redirect fallthru edge.  */
    1507                 :    3258890 :   if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
    1508                 :    3258870 :       && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)
    1509                 :    3258870 :       && any_condjump_p (BB_END (e->src))
    1510                 :    3755000 :       && JUMP_LABEL (BB_END (e->src)) == BB_HEAD (e->dest))
    1511                 :            :     {
    1512                 :          0 :       rtx note;
    1513                 :          0 :       edge b = unchecked_make_edge (e->src, target, 0);
    1514                 :          0 :       bool redirected;
    1515                 :            : 
    1516                 :          0 :       redirected = redirect_jump (as_a <rtx_jump_insn *> (BB_END (e->src)),
    1517                 :          0 :                                   block_label (target), 0);
    1518                 :          0 :       gcc_assert (redirected);
    1519                 :            : 
    1520                 :          0 :       note = find_reg_note (BB_END (e->src), REG_BR_PROB, NULL_RTX);
    1521                 :          0 :       if (note)
    1522                 :            :         {
    1523                 :          0 :           int prob = XINT (note, 0);
    1524                 :            : 
    1525                 :          0 :           b->probability = profile_probability::from_reg_br_prob_note (prob);
    1526                 :          0 :           e->probability -= e->probability;
    1527                 :            :         }
    1528                 :            :     }
    1529                 :            : 
    1530                 :    3258890 :   if (e->flags & EDGE_ABNORMAL)
    1531                 :            :     {
    1532                 :            :       /* Irritating special case - fallthru edge to the same block as abnormal
    1533                 :            :          edge.
    1534                 :            :          We can't redirect abnormal edge, but we still can split the fallthru
    1535                 :            :          one and create separate abnormal edge to original destination.
    1536                 :            :          This allows bb-reorder to make such edge non-fallthru.  */
    1537                 :          0 :       gcc_assert (e->dest == target);
    1538                 :          0 :       abnormal_edge_flags = e->flags & ~EDGE_FALLTHRU;
    1539                 :          0 :       e->flags &= EDGE_FALLTHRU;
    1540                 :            :     }
    1541                 :            :   else
    1542                 :            :     {
    1543                 :    3258890 :       gcc_assert (e->flags & EDGE_FALLTHRU);
    1544                 :    3258890 :       if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun))
    1545                 :            :         {
    1546                 :            :           /* We can't redirect the entry block.  Create an empty block
    1547                 :            :              at the start of the function which we use to add the new
    1548                 :            :              jump.  */
    1549                 :         23 :           edge tmp;
    1550                 :         23 :           edge_iterator ei;
    1551                 :         23 :           bool found = false;
    1552                 :            : 
    1553                 :         23 :           basic_block bb = create_basic_block (BB_HEAD (e->dest), NULL,
    1554                 :            :                                                ENTRY_BLOCK_PTR_FOR_FN (cfun));
    1555                 :         23 :           bb->count = ENTRY_BLOCK_PTR_FOR_FN (cfun)->count;
    1556                 :            : 
    1557                 :            :           /* Make sure new block ends up in correct hot/cold section.  */
    1558                 :         23 :           BB_COPY_PARTITION (bb, e->dest);
    1559                 :            : 
    1560                 :            :           /* Change the existing edge's source to be the new block, and add
    1561                 :            :              a new edge from the entry block to the new block.  */
    1562                 :         23 :           e->src = bb;
    1563                 :         23 :           for (ei = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs);
    1564                 :         23 :                (tmp = ei_safe_edge (ei)); )
    1565                 :            :             {
    1566                 :         23 :               if (tmp == e)
    1567                 :            :                 {
    1568                 :         23 :                   ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs->unordered_remove (ei.index);
    1569                 :         23 :                   found = true;
    1570                 :         23 :                   break;
    1571                 :            :                 }
    1572                 :            :               else
    1573                 :          0 :                 ei_next (&ei);
    1574                 :            :             }
    1575                 :            : 
    1576                 :          0 :           gcc_assert (found);
    1577                 :            : 
    1578                 :         23 :           vec_safe_push (bb->succs, e);
    1579                 :         23 :           make_single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun), bb,
    1580                 :            :                                  EDGE_FALLTHRU);
    1581                 :            :         }
    1582                 :            :     }
    1583                 :            : 
    1584                 :            :   /* If e->src ends with asm goto, see if any of the ASM_OPERANDS_LABELs
    1585                 :            :      don't point to the target or fallthru label.  */
    1586                 :    3258890 :   if (JUMP_P (BB_END (e->src))
    1587                 :     496184 :       && target != EXIT_BLOCK_PTR_FOR_FN (cfun)
    1588                 :     496184 :       && (e->flags & EDGE_FALLTHRU)
    1589                 :    3755070 :       && (note = extract_asm_operands (PATTERN (BB_END (e->src)))))
    1590                 :            :     {
    1591                 :         76 :       int i, n = ASM_OPERANDS_LABEL_LENGTH (note);
    1592                 :         76 :       bool adjust_jump_target = false;
    1593                 :            : 
    1594                 :        181 :       for (i = 0; i < n; ++i)
    1595                 :            :         {
    1596                 :        105 :           if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (e->dest))
    1597                 :            :             {
    1598                 :         25 :               LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))--;
    1599                 :         25 :               XEXP (ASM_OPERANDS_LABEL (note, i), 0) = block_label (target);
    1600                 :         25 :               LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))++;
    1601                 :         25 :               adjust_jump_target = true;
    1602                 :            :             }
    1603                 :        105 :           if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (target))
    1604                 :         25 :             asm_goto_edge = true;
    1605                 :            :         }
    1606                 :         76 :       if (adjust_jump_target)
    1607                 :            :         {
    1608                 :         24 :           rtx_insn *insn = BB_END (e->src);
    1609                 :         24 :           rtx note;
    1610                 :         24 :           rtx_insn *old_label = BB_HEAD (e->dest);
    1611                 :         24 :           rtx_insn *new_label = BB_HEAD (target);
    1612                 :            : 
    1613                 :         24 :           if (JUMP_LABEL (insn) == old_label)
    1614                 :            :             {
    1615                 :         16 :               JUMP_LABEL (insn) = new_label;
    1616                 :         16 :               note = find_reg_note (insn, REG_LABEL_TARGET, new_label);
    1617                 :         16 :               if (note)
    1618                 :          0 :                 remove_note (insn, note);
    1619                 :            :             }
    1620                 :            :           else
    1621                 :            :             {
    1622                 :          8 :               note = find_reg_note (insn, REG_LABEL_TARGET, old_label);
    1623                 :          8 :               if (note)
    1624                 :          8 :                 remove_note (insn, note);
    1625                 :          8 :               if (JUMP_LABEL (insn) != new_label
    1626                 :          8 :                   && !find_reg_note (insn, REG_LABEL_TARGET, new_label))
    1627                 :          8 :                 add_reg_note (insn, REG_LABEL_TARGET, new_label);
    1628                 :            :             }
    1629                 :         48 :           while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label))
    1630                 :         24 :                  != NULL_RTX)
    1631                 :          0 :             XEXP (note, 0) = new_label;
    1632                 :            :         }
    1633                 :            :     }
    1634                 :            : 
    1635                 :    3258890 :   if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags || asm_goto_edge)
    1636                 :            :     {
    1637                 :     611373 :       rtx_insn *new_head;
    1638                 :     611373 :       profile_count count = e->count ();
    1639                 :     611373 :       profile_probability probability = e->probability;
    1640                 :            :       /* Create the new structures.  */
    1641                 :            : 
    1642                 :            :       /* If the old block ended with a tablejump, skip its table
    1643                 :            :          by searching forward from there.  Otherwise start searching
    1644                 :            :          forward from the last instruction of the old block.  */
    1645                 :     611373 :       rtx_jump_table_data *table;
    1646                 :     611373 :       if (tablejump_p (BB_END (e->src), NULL, &table))
    1647                 :          0 :         new_head = table;
    1648                 :            :       else
    1649                 :     611373 :         new_head = BB_END (e->src);
    1650                 :     611373 :       new_head = NEXT_INSN (new_head);
    1651                 :            : 
    1652                 :     611373 :       jump_block = create_basic_block (new_head, NULL, e->src);
    1653                 :     611373 :       jump_block->count = count;
    1654                 :            : 
    1655                 :            :       /* Make sure new block ends up in correct hot/cold section.  */
    1656                 :            : 
    1657                 :     611373 :       BB_COPY_PARTITION (jump_block, e->src);
    1658                 :            : 
    1659                 :            :       /* Wire edge in.  */
    1660                 :     611373 :       new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU);
    1661                 :     611373 :       new_edge->probability = probability;
    1662                 :            : 
    1663                 :            :       /* Redirect old edge.  */
    1664                 :     611373 :       redirect_edge_pred (e, jump_block);
    1665                 :     611373 :       e->probability = profile_probability::always ();
    1666                 :            : 
    1667                 :            :       /* If e->src was previously region crossing, it no longer is
    1668                 :            :          and the reg crossing note should be removed.  */
    1669                 :     611373 :       fixup_partition_crossing (new_edge);
    1670                 :            : 
    1671                 :            :       /* If asm goto has any label refs to target's label,
    1672                 :            :          add also edge from asm goto bb to target.  */
    1673                 :     611373 :       if (asm_goto_edge)
    1674                 :            :         {
    1675                 :         24 :           new_edge->probability = new_edge->probability.apply_scale (1, 2);
    1676                 :         24 :           jump_block->count = jump_block->count.apply_scale (1, 2);
    1677                 :         48 :           edge new_edge2 = make_edge (new_edge->src, target,
    1678                 :         24 :                                       e->flags & ~EDGE_FALLTHRU);
    1679                 :         24 :           new_edge2->probability = probability - new_edge->probability;
    1680                 :            :         }
    1681                 :            : 
    1682                 :     611373 :       new_bb = jump_block;
    1683                 :            :     }
    1684                 :            :   else
    1685                 :            :     jump_block = e->src;
    1686                 :            : 
    1687                 :    3258890 :   loc = e->goto_locus;
    1688                 :    3258890 :   e->flags &= ~EDGE_FALLTHRU;
    1689                 :    3258890 :   if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
    1690                 :            :     {
    1691                 :          0 :       if (jump_label == ret_rtx)
    1692                 :          0 :         emit_jump_insn_after_setloc (targetm.gen_return (),
    1693                 :          0 :                                      BB_END (jump_block), loc);
    1694                 :            :       else
    1695                 :            :         {
    1696                 :          0 :           gcc_assert (jump_label == simple_return_rtx);
    1697                 :          0 :           emit_jump_insn_after_setloc (targetm.gen_simple_return (),
    1698                 :          0 :                                        BB_END (jump_block), loc);
    1699                 :            :         }
    1700                 :          0 :       set_return_jump_label (BB_END (jump_block));
    1701                 :            :     }
    1702                 :            :   else
    1703                 :            :     {
    1704                 :    3258890 :       rtx_code_label *label = block_label (target);
    1705                 :    3258890 :       emit_jump_insn_after_setloc (targetm.gen_jump (label),
    1706                 :    3258890 :                                    BB_END (jump_block), loc);
    1707                 :    3258890 :       JUMP_LABEL (BB_END (jump_block)) = label;
    1708                 :    3258890 :       LABEL_NUSES (label)++;
    1709                 :            :     }
    1710                 :            : 
    1711                 :            :   /* We might be in cfg layout mode, and if so, the following routine will
    1712                 :            :      insert the barrier correctly.  */
    1713                 :    3258890 :   emit_barrier_after_bb (jump_block);
    1714                 :    3258890 :   redirect_edge_succ_nodup (e, target);
    1715                 :            : 
    1716                 :    3258890 :   if (abnormal_edge_flags)
    1717                 :          0 :     make_edge (src, target, abnormal_edge_flags);
    1718                 :            : 
    1719                 :    3258890 :   df_mark_solutions_dirty ();
    1720                 :    3258890 :   fixup_partition_crossing (e);
    1721                 :    3258890 :   return new_bb;
    1722                 :            : }
    1723                 :            : 
    1724                 :            : /* Edge E is assumed to be fallthru edge.  Emit needed jump instruction
    1725                 :            :    (and possibly create new basic block) to make edge non-fallthru.
    1726                 :            :    Return newly created BB or NULL if none.  */
    1727                 :            : 
    1728                 :            : static basic_block
    1729                 :     512838 : rtl_force_nonfallthru (edge e)
    1730                 :            : {
    1731                 :     512838 :   return force_nonfallthru_and_redirect (e, e->dest, NULL_RTX);
    1732                 :            : }
    1733                 :            : 
    1734                 :            : /* Redirect edge even at the expense of creating new jump insn or
    1735                 :            :    basic block.  Return new basic block if created, NULL otherwise.
    1736                 :            :    Conversion must be possible.  */
    1737                 :            : 
    1738                 :            : static basic_block
    1739                 :     241179 : rtl_redirect_edge_and_branch_force (edge e, basic_block target)
    1740                 :            : {
    1741                 :     241179 :   if (redirect_edge_and_branch (e, target)
    1742                 :     241179 :       || e->dest == target)
    1743                 :            :     return NULL;
    1744                 :            : 
    1745                 :            :   /* In case the edge redirection failed, try to force it to be non-fallthru
    1746                 :            :      and redirect newly created simplejump.  */
    1747                 :     210591 :   df_set_bb_dirty (e->src);
    1748                 :     210591 :   return force_nonfallthru_and_redirect (e, target, NULL_RTX);
    1749                 :            : }
    1750                 :            : 
    1751                 :            : /* The given edge should potentially be a fallthru edge.  If that is in
    1752                 :            :    fact true, delete the jump and barriers that are in the way.  */
    1753                 :            : 
    1754                 :            : static void
    1755                 :     308484 : rtl_tidy_fallthru_edge (edge e)
    1756                 :            : {
    1757                 :     308484 :   rtx_insn *q;
    1758                 :     308484 :   basic_block b = e->src, c = b->next_bb;
    1759                 :            : 
    1760                 :            :   /* ??? In a late-running flow pass, other folks may have deleted basic
    1761                 :            :      blocks by nopping out blocks, leaving multiple BARRIERs between here
    1762                 :            :      and the target label. They ought to be chastised and fixed.
    1763                 :            : 
    1764                 :            :      We can also wind up with a sequence of undeletable labels between
    1765                 :            :      one block and the next.
    1766                 :            : 
    1767                 :            :      So search through a sequence of barriers, labels, and notes for
    1768                 :            :      the head of block C and assert that we really do fall through.  */
    1769                 :            : 
    1770                 :     320098 :   for (q = NEXT_INSN (BB_END (b)); q != BB_HEAD (c); q = NEXT_INSN (q))
    1771                 :       5807 :     if (NONDEBUG_INSN_P (q))
    1772                 :            :       return;
    1773                 :            : 
    1774                 :            :   /* Remove what will soon cease being the jump insn from the source block.
    1775                 :            :      If block B consisted only of this single jump, turn it into a deleted
    1776                 :            :      note.  */
    1777                 :     308484 :   q = BB_END (b);
    1778                 :     308484 :   if (JUMP_P (q)
    1779                 :      11676 :       && onlyjump_p (q)
    1780                 :     320152 :       && (any_uncondjump_p (q)
    1781                 :       5928 :           || single_succ_p (b)))
    1782                 :            :     {
    1783                 :       5815 :       rtx_insn *label;
    1784                 :       5815 :       rtx_jump_table_data *table;
    1785                 :            : 
    1786                 :       5815 :       if (tablejump_p (q, &label, &table))
    1787                 :            :         {
    1788                 :            :           /* The label is likely mentioned in some instruction before
    1789                 :            :              the tablejump and might not be DCEd, so turn it into
    1790                 :            :              a note instead and move before the tablejump that is going to
    1791                 :            :              be deleted.  */
    1792                 :          0 :           const char *name = LABEL_NAME (label);
    1793                 :          0 :           PUT_CODE (label, NOTE);
    1794                 :          0 :           NOTE_KIND (label) = NOTE_INSN_DELETED_LABEL;
    1795                 :          0 :           NOTE_DELETED_LABEL_NAME (label) = name;
    1796                 :          0 :           reorder_insns (label, label, PREV_INSN (q));
    1797                 :          0 :           delete_insn (table);
    1798                 :            :         }
    1799                 :            : 
    1800                 :            :       /* If this was a conditional jump, we need to also delete
    1801                 :            :          the insn that set cc0.  */
    1802                 :       5815 :       if (HAVE_cc0 && any_condjump_p (q) && only_sets_cc0_p (PREV_INSN (q)))
    1803                 :            :         q = PREV_INSN (q);
    1804                 :            : 
    1805                 :       5815 :       q = PREV_INSN (q);
    1806                 :            :     }
    1807                 :            :   /* Unconditional jumps with side-effects (i.e. which we can't just delete
    1808                 :            :      together with the barrier) should never have a fallthru edge.  */
    1809                 :     302669 :   else if (JUMP_P (q) && any_uncondjump_p (q))
    1810                 :            :     return;
    1811                 :            : 
    1812                 :            :   /* Selectively unlink the sequence.  */
    1813                 :     308484 :   if (q != PREV_INSN (BB_HEAD (c)))
    1814                 :       5834 :     delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c)), false);
    1815                 :            : 
    1816                 :     308484 :   e->flags |= EDGE_FALLTHRU;
    1817                 :            : }
    1818                 :            : 
    1819                 :            : /* Should move basic block BB after basic block AFTER.  NIY.  */
    1820                 :            : 
    1821                 :            : static bool
    1822                 :     339843 : rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED,
    1823                 :            :                       basic_block after ATTRIBUTE_UNUSED)
    1824                 :            : {
    1825                 :     339843 :   return false;
    1826                 :            : }
    1827                 :            : 
    1828                 :            : /* Locate the last bb in the same partition as START_BB.  */
    1829                 :            : 
    1830                 :            : static basic_block
    1831                 :          0 : last_bb_in_partition (basic_block start_bb)
    1832                 :            : {
    1833                 :          0 :   basic_block bb;
    1834                 :          0 :   FOR_BB_BETWEEN (bb, start_bb, EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
    1835                 :            :     {
    1836                 :   24354100 :       if (BB_PARTITION (start_bb) != BB_PARTITION (bb->next_bb))
    1837                 :          0 :         return bb;
    1838                 :            :     }
    1839                 :            :   /* Return bb before the exit block.  */
    1840                 :          0 :   return bb->prev_bb;
    1841                 :            : }
    1842                 :            : 
    1843                 :            : /* Split a (typically critical) edge.  Return the new block.
    1844                 :            :    The edge must not be abnormal.
    1845                 :            : 
    1846                 :            :    ??? The code generally expects to be called on critical edges.
    1847                 :            :    The case of a block ending in an unconditional jump to a
    1848                 :            :    block with multiple predecessors is not handled optimally.  */
    1849                 :            : 
    1850                 :            : static basic_block
    1851                 :     719391 : rtl_split_edge (edge edge_in)
    1852                 :            : {
    1853                 :     719391 :   basic_block bb, new_bb;
    1854                 :     719391 :   rtx_insn *before;
    1855                 :            : 
    1856                 :            :   /* Abnormal edges cannot be split.  */
    1857                 :     719391 :   gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
    1858                 :            : 
    1859                 :            :   /* We are going to place the new block in front of edge destination.
    1860                 :            :      Avoid existence of fallthru predecessors.  */
    1861                 :     719391 :   if ((edge_in->flags & EDGE_FALLTHRU) == 0)
    1862                 :            :     {
    1863                 :     459295 :       edge e = find_fallthru_edge (edge_in->dest->preds);
    1864                 :            : 
    1865                 :     459295 :       if (e)
    1866                 :     343251 :         force_nonfallthru (e);
    1867                 :            :     }
    1868                 :            : 
    1869                 :            :   /* Create the basic block note.  */
    1870                 :     719391 :   if (edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
    1871                 :     578721 :     before = BB_HEAD (edge_in->dest);
    1872                 :            :   else
    1873                 :            :     before = NULL;
    1874                 :            : 
    1875                 :            :   /* If this is a fall through edge to the exit block, the blocks might be
    1876                 :            :      not adjacent, and the right place is after the source.  */
    1877                 :     719391 :   if ((edge_in->flags & EDGE_FALLTHRU)
    1878                 :     260096 :       && edge_in->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
    1879                 :            :     {
    1880                 :     140670 :       before = NEXT_INSN (BB_END (edge_in->src));
    1881                 :     140670 :       bb = create_basic_block (before, NULL, edge_in->src);
    1882                 :     140670 :       BB_COPY_PARTITION (bb, edge_in->src);
    1883                 :            :     }
    1884                 :            :   else
    1885                 :            :     {
    1886                 :     578721 :       if (edge_in->src == ENTRY_BLOCK_PTR_FOR_FN (cfun))
    1887                 :            :         {
    1888                 :      53409 :           bb = create_basic_block (before, NULL, edge_in->dest->prev_bb);
    1889                 :      53409 :           BB_COPY_PARTITION (bb, edge_in->dest);
    1890                 :            :         }
    1891                 :            :       else
    1892                 :            :         {
    1893                 :     525312 :           basic_block after = edge_in->dest->prev_bb;
    1894                 :            :           /* If this is post-bb reordering, and the edge crosses a partition
    1895                 :            :              boundary, the new block needs to be inserted in the bb chain
    1896                 :            :              at the end of the src partition (since we put the new bb into
    1897                 :            :              that partition, see below). Otherwise we may end up creating
    1898                 :            :              an extra partition crossing in the chain, which is illegal.
    1899                 :            :              It can't go after the src, because src may have a fall-through
    1900                 :            :              to a different block.  */
    1901                 :     525312 :           if (crtl->bb_reorder_complete
    1902                 :      71347 :               && (edge_in->flags & EDGE_CROSSING))
    1903                 :            :             {
    1904                 :   24354100 :               after = last_bb_in_partition (edge_in->src);
    1905                 :      37150 :               before = get_last_bb_insn (after);
    1906                 :            :               /* The instruction following the last bb in partition should
    1907                 :            :                  be a barrier, since it cannot end in a fall-through.  */
    1908                 :      37150 :               gcc_checking_assert (BARRIER_P (before));
    1909                 :      37150 :               before = NEXT_INSN (before);
    1910                 :            :             }
    1911                 :     525312 :           bb = create_basic_block (before, NULL, after);
    1912                 :            :           /* Put the split bb into the src partition, to avoid creating
    1913                 :            :              a situation where a cold bb dominates a hot bb, in the case
    1914                 :            :              where src is cold and dest is hot. The src will dominate
    1915                 :            :              the new bb (whereas it might not have dominated dest).  */
    1916                 :     525312 :           BB_COPY_PARTITION (bb, edge_in->src);
    1917                 :            :         }
    1918                 :            :     }
    1919                 :            : 
    1920                 :     719391 :   make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU);
    1921                 :            : 
    1922                 :            :   /* Can't allow a region crossing edge to be fallthrough.  */
    1923                 :     719391 :   if (BB_PARTITION (bb) != BB_PARTITION (edge_in->dest)
    1924                 :      65422 :       && edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
    1925                 :            :     {
    1926                 :      37176 :       new_bb = force_nonfallthru (single_succ_edge (bb));
    1927                 :      37176 :       gcc_assert (!new_bb);
    1928                 :            :     }
    1929                 :            : 
    1930                 :            :   /* For non-fallthru edges, we must adjust the predecessor's
    1931                 :            :      jump instruction to target our new block.  */
    1932                 :     719391 :   if ((edge_in->flags & EDGE_FALLTHRU) == 0)
    1933                 :            :     {
    1934                 :     459295 :       edge redirected = redirect_edge_and_branch (edge_in, bb);
    1935                 :     459295 :       gcc_assert (redirected);
    1936                 :            :     }
    1937                 :            :   else
    1938                 :            :     {
    1939                 :     260096 :       if (edge_in->src != ENTRY_BLOCK_PTR_FOR_FN (cfun))
    1940                 :            :         {
    1941                 :            :           /* For asm goto even splitting of fallthru edge might
    1942                 :            :              need insn patching, as other labels might point to the
    1943                 :            :              old label.  */
    1944                 :     206687 :           rtx_insn *last = BB_END (edge_in->src);
    1945                 :     206687 :           if (last
    1946                 :     206687 :               && JUMP_P (last)
    1947                 :      82470 :               && edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)
    1948                 :      59412 :               && (extract_asm_operands (PATTERN (last))
    1949                 :      59410 :                   || JUMP_LABEL (last) == before)
    1950                 :     206689 :               && patch_jump_insn (last, before, bb))
    1951                 :          2 :             df_set_bb_dirty (edge_in->src);
    1952                 :            :         }
    1953                 :     260096 :       redirect_edge_succ (edge_in, bb);
    1954                 :            :     }
    1955                 :            : 
    1956                 :     719391 :   return bb;
    1957                 :            : }
    1958                 :            : 
    1959                 :            : /* Queue instructions for insertion on an edge between two basic blocks.
    1960                 :            :    The new instructions and basic blocks (if any) will not appear in the
    1961                 :            :    CFG until commit_edge_insertions is called.  */
    1962                 :            : 
    1963                 :            : void
    1964                 :    3339680 : insert_insn_on_edge (rtx pattern, edge e)
    1965                 :            : {
    1966                 :            :   /* We cannot insert instructions on an abnormal critical edge.
    1967                 :            :      It will be easier to find the culprit if we die now.  */
    1968                 :    3339680 :   gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e)));
    1969                 :            : 
    1970                 :    3339680 :   if (e->insns.r == NULL_RTX)
    1971                 :    2898590 :     start_sequence ();
    1972                 :            :   else
    1973                 :     441087 :     push_to_sequence (e->insns.r);
    1974                 :            : 
    1975                 :    3339680 :   emit_insn (pattern);
    1976                 :            : 
    1977                 :    3339680 :   e->insns.r = get_insns ();
    1978                 :    3339680 :   end_sequence ();
    1979                 :    3339680 : }
    1980                 :            : 
    1981                 :            : /* Update the CFG for the instructions queued on edge E.  */
    1982                 :            : 
    1983                 :            : void
    1984                 :    2898580 : commit_one_edge_insertion (edge e)
    1985                 :            : {
    1986                 :    2898580 :   rtx_insn *before = NULL, *after = NULL, *insns, *tmp, *last;
    1987                 :    2898580 :   basic_block bb;
    1988                 :            : 
    1989                 :            :   /* Pull the insns off the edge now since the edge might go away.  */
    1990                 :    2898580 :   insns = e->insns.r;
    1991                 :    2898580 :   e->insns.r = NULL;
    1992                 :            : 
    1993                 :            :   /* Figure out where to put these insns.  If the destination has
    1994                 :            :      one predecessor, insert there.  Except for the exit block.  */
    1995                 :    2898580 :   if (single_pred_p (e->dest) && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
    1996                 :            :     {
    1997                 :    1037340 :       bb = e->dest;
    1998                 :            : 
    1999                 :            :       /* Get the location correct wrt a code label, and "nice" wrt
    2000                 :            :          a basic block note, and before everything else.  */
    2001                 :    1037340 :       tmp = BB_HEAD (bb);
    2002                 :    1037340 :       if (LABEL_P (tmp))
    2003                 :      44885 :         tmp = NEXT_INSN (tmp);
    2004                 :    1037340 :       if (NOTE_INSN_BASIC_BLOCK_P (tmp))
    2005                 :    1037340 :         tmp = NEXT_INSN (tmp);
    2006                 :    1037340 :       if (tmp == BB_HEAD (bb))
    2007                 :            :         before = tmp;
    2008                 :    1037340 :       else if (tmp)
    2009                 :    1037340 :         after = PREV_INSN (tmp);
    2010                 :            :       else
    2011                 :          0 :         after = get_last_insn ();
    2012                 :            :     }
    2013                 :            : 
    2014                 :            :   /* If the source has one successor and the edge is not abnormal,
    2015                 :            :      insert there.  Except for the entry block.
    2016                 :            :      Don't do this if the predecessor ends in a jump other than
    2017                 :            :      unconditional simple jump.  E.g. for asm goto that points all
    2018                 :            :      its labels at the fallthru basic block, we can't insert instructions
    2019                 :            :      before the asm goto, as the asm goto can have various of side effects,
    2020                 :            :      and can't emit instructions after the asm goto, as it must end
    2021                 :            :      the basic block.  */
    2022                 :    1861240 :   else if ((e->flags & EDGE_ABNORMAL) == 0
    2023                 :    1861240 :            && single_succ_p (e->src)
    2024                 :    1335600 :            && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
    2025                 :    3195740 :            && (!JUMP_P (BB_END (e->src))
    2026                 :     171135 :                || simplejump_p (BB_END (e->src))))
    2027                 :            :     {
    2028                 :    1334490 :       bb = e->src;
    2029                 :            : 
    2030                 :            :       /* It is possible to have a non-simple jump here.  Consider a target
    2031                 :            :          where some forms of unconditional jumps clobber a register.  This
    2032                 :            :          happens on the fr30 for example.
    2033                 :            : 
    2034                 :            :          We know this block has a single successor, so we can just emit
    2035                 :            :          the queued insns before the jump.  */
    2036                 :    1334490 :       if (JUMP_P (BB_END (bb)))
    2037                 :            :         before = BB_END (bb);
    2038                 :            :       else
    2039                 :            :         {
    2040                 :            :           /* We'd better be fallthru, or we've lost track of what's what.  */
    2041                 :    1163360 :           gcc_assert (e->flags & EDGE_FALLTHRU);
    2042                 :            : 
    2043                 :            :           after = BB_END (bb);
    2044                 :            :         }
    2045                 :            :     }
    2046                 :            : 
    2047                 :            :   /* Otherwise we must split the edge.  */
    2048                 :            :   else
    2049                 :            :     {
    2050                 :     526753 :       bb = split_edge (e);
    2051                 :            : 
    2052                 :            :       /* If E crossed a partition boundary, we needed to make bb end in
    2053                 :            :          a region-crossing jump, even though it was originally fallthru.  */
    2054                 :     526753 :       if (JUMP_P (BB_END (bb)))
    2055                 :            :         before = BB_END (bb);
    2056                 :            :       else
    2057                 :     489577 :         after = BB_END (bb);
    2058                 :            :     }
    2059                 :            : 
    2060                 :            :   /* Now that we've found the spot, do the insertion.  */
    2061                 :    2898580 :   if (before)
    2062                 :            :     {
    2063                 :     208307 :       emit_insn_before_noloc (insns, before, bb);
    2064                 :     208307 :       last = prev_nonnote_insn (before);
    2065                 :            :     }
    2066                 :            :   else
    2067                 :    2690280 :     last = emit_insn_after_noloc (insns, after, bb);
    2068                 :            : 
    2069                 :    2898580 :   if (returnjump_p (last))
    2070                 :            :     {
    2071                 :            :       /* ??? Remove all outgoing edges from BB and add one for EXIT.
    2072                 :            :          This is not currently a problem because this only happens
    2073                 :            :          for the (single) epilogue, which already has a fallthru edge
    2074                 :            :          to EXIT.  */
    2075                 :            : 
    2076                 :     859853 :       e = single_succ_edge (bb);
    2077                 :     859853 :       gcc_assert (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)
    2078                 :            :                   && single_succ_p (bb) && (e->flags & EDGE_FALLTHRU));
    2079                 :            : 
    2080                 :     859853 :       e->flags &= ~EDGE_FALLTHRU;
    2081                 :     859853 :       emit_barrier_after (last);
    2082                 :            : 
    2083                 :     859853 :       if (before)
    2084                 :          0 :         delete_insn (before);
    2085                 :            :     }
    2086                 :            :   else
    2087                 :    2038730 :     gcc_assert (!JUMP_P (last));
    2088                 :    2898580 : }
    2089                 :            : 
    2090                 :            : /* Update the CFG for all queued instructions.  */
    2091                 :            : 
    2092                 :            : void
    2093                 :    2900630 : commit_edge_insertions (void)
    2094                 :            : {
    2095                 :    2900630 :   basic_block bb;
    2096                 :            : 
    2097                 :            :   /* Optimization passes that invoke this routine can cause hot blocks
    2098                 :            :      previously reached by both hot and cold blocks to become dominated only
    2099                 :            :      by cold blocks. This will cause the verification below to fail,
    2100                 :            :      and lead to now cold code in the hot section. In some cases this
    2101                 :            :      may only be visible after newly unreachable blocks are deleted,
    2102                 :            :      which will be done by fixup_partitions.  */
    2103                 :    2900630 :   fixup_partitions ();
    2104                 :            : 
    2105                 :    2900630 :   if (!currently_expanding_to_rtl)
    2106                 :    1957260 :     checking_verify_flow_info ();
    2107                 :            : 
    2108                 :   40304900 :   FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun),
    2109                 :            :                   EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
    2110                 :            :     {
    2111                 :   37404300 :       edge e;
    2112                 :   37404300 :       edge_iterator ei;
    2113                 :            : 
    2114                 :   89081500 :       FOR_EACH_EDGE (e, ei, bb->succs)
    2115                 :   51677200 :         if (e->insns.r)
    2116                 :            :           {
    2117                 :    2867790 :             if (currently_expanding_to_rtl)
    2118                 :     670944 :               rebuild_jump_labels_chain (e->insns.r);
    2119                 :    2867790 :             commit_one_edge_insertion (e);
    2120                 :            :           }
    2121                 :            :     }
    2122                 :    2900630 : }
    2123                 :            : 
    2124                 :            : 
    2125                 :            : /* Print out RTL-specific basic block information (live information
    2126                 :            :    at start and end with TDF_DETAILS).  FLAGS are the TDF_* masks
    2127                 :            :    documented in dumpfile.h.  */
    2128                 :            : 
    2129                 :            : static void
    2130                 :       2723 : rtl_dump_bb (FILE *outf, basic_block bb, int indent, dump_flags_t flags)
    2131                 :            : {
    2132                 :       2723 :   char *s_indent;
    2133                 :            : 
    2134                 :       2723 :   s_indent = (char *) alloca ((size_t) indent + 1);
    2135                 :       2723 :   memset (s_indent, ' ', (size_t) indent);
    2136                 :       2723 :   s_indent[indent] = '\0';
    2137                 :            : 
    2138                 :       2723 :   if (df && (flags & TDF_DETAILS))
    2139                 :            :     {
    2140                 :        743 :       df_dump_top (bb, outf);
    2141                 :        743 :       putc ('\n', outf);
    2142                 :            :     }
    2143                 :            : 
    2144                 :       2723 :   if (bb->index != ENTRY_BLOCK && bb->index != EXIT_BLOCK)
    2145                 :            :     {
    2146                 :       2133 :       rtx_insn *last = BB_END (bb);
    2147                 :       2133 :       if (last)
    2148                 :       2133 :         last = NEXT_INSN (last);
    2149                 :      29957 :       for (rtx_insn *insn = BB_HEAD (bb); insn != last; insn = NEXT_INSN (insn))
    2150                 :            :         {
    2151                 :      13912 :           if (flags & TDF_DETAILS)
    2152                 :       4337 :             df_dump_insn_top (insn, outf);
    2153                 :      13912 :           if (! (flags & TDF_SLIM))
    2154                 :      13880 :             print_rtl_single (outf, insn);
    2155                 :            :           else
    2156                 :         32 :             dump_insn_slim (outf, insn);
    2157                 :      13912 :           if (flags & TDF_DETAILS)
    2158                 :       4337 :             df_dump_insn_bottom (insn, outf);
    2159                 :            :         }
    2160                 :            :     }
    2161                 :            : 
    2162                 :       2723 :   if (df && (flags & TDF_DETAILS))
    2163                 :            :     {
    2164                 :        743 :       df_dump_bottom (bb, outf);
    2165                 :        743 :       putc ('\n', outf);
    2166                 :            :     }
    2167                 :            : 
    2168                 :       2723 : }
    2169                 :            : 
    2170                 :            : /* Like dump_function_to_file, but for RTL.  Print out dataflow information
    2171                 :            :    for the start of each basic block.  FLAGS are the TDF_* masks documented
    2172                 :            :    in dumpfile.h.  */
    2173                 :            : 
    2174                 :            : void
    2175                 :       3519 : print_rtl_with_bb (FILE *outf, const rtx_insn *rtx_first, dump_flags_t flags)
    2176                 :            : {
    2177                 :       3519 :   const rtx_insn *tmp_rtx;
    2178                 :       3519 :   if (rtx_first == 0)
    2179                 :          0 :     fprintf (outf, "(nil)\n");
    2180                 :            :   else
    2181                 :            :     {
    2182                 :       3519 :       enum bb_state { NOT_IN_BB, IN_ONE_BB, IN_MULTIPLE_BB };
    2183                 :       3519 :       int max_uid = get_max_uid ();
    2184                 :       3519 :       basic_block *start = XCNEWVEC (basic_block, max_uid);
    2185                 :       3519 :       basic_block *end = XCNEWVEC (basic_block, max_uid);
    2186                 :       3519 :       enum bb_state *in_bb_p = XCNEWVEC (enum bb_state, max_uid);
    2187                 :       3519 :       basic_block bb;
    2188                 :            : 
    2189                 :            :       /* After freeing the CFG, we still have BLOCK_FOR_INSN set on most
    2190                 :            :          insns, but the CFG is not maintained so the basic block info
    2191                 :            :          is not reliable.  Therefore it's omitted from the dumps.  */
    2192                 :       3519 :       if (! (cfun->curr_properties & PROP_cfg))
    2193                 :        659 :         flags &= ~TDF_BLOCKS;
    2194                 :            : 
    2195                 :       3519 :       if (df)
    2196                 :       2766 :         df_dump_start (outf);
    2197                 :            : 
    2198                 :       3519 :       if (cfun->curr_properties & PROP_cfg)
    2199                 :            :         {
    2200                 :      19396 :           FOR_EACH_BB_REVERSE_FN (bb, cfun)
    2201                 :            :             {
    2202                 :      16536 :               rtx_insn *x;
    2203                 :            : 
    2204                 :      16536 :               start[INSN_UID (BB_HEAD (bb))] = bb;
    2205                 :      16536 :               end[INSN_UID (BB_END (bb))] = bb;
    2206                 :      16536 :               if (flags & TDF_BLOCKS)
    2207                 :            :                 {
    2208                 :      11261 :                   for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x))
    2209                 :            :                     {
    2210                 :       6109 :                       enum bb_state state = IN_MULTIPLE_BB;
    2211                 :            : 
    2212                 :       6109 :                       if (in_bb_p[INSN_UID (x)] == NOT_IN_BB)
    2213                 :       6109 :                         state = IN_ONE_BB;
    2214                 :       6109 :                       in_bb_p[INSN_UID (x)] = state;
    2215                 :            : 
    2216                 :       6109 :                       if (x == BB_END (bb))
    2217                 :            :                         break;
    2218                 :            :                     }
    2219                 :            :                 }
    2220                 :            :             }
    2221                 :            :         }
    2222                 :            : 
    2223                 :     146370 :       for (tmp_rtx = rtx_first; tmp_rtx != NULL; tmp_rtx = NEXT_INSN (tmp_rtx))
    2224                 :            :         {
    2225                 :     142851 :           if (flags & TDF_BLOCKS)
    2226                 :            :             {
    2227                 :       6928 :               bb = start[INSN_UID (tmp_rtx)];
    2228                 :       6928 :               if (bb != NULL)
    2229                 :            :                 {
    2230                 :        957 :                   dump_bb_info (outf, bb, 0, dump_flags, true, false);
    2231                 :        957 :                   if (df && (flags & TDF_DETAILS))
    2232                 :        578 :                     df_dump_top (bb, outf);
    2233                 :            :                 }
    2234                 :            : 
    2235                 :       6928 :               if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB
    2236                 :        819 :                   && !NOTE_P (tmp_rtx)
    2237                 :       7123 :                   && !BARRIER_P (tmp_rtx))
    2238                 :          0 :                 fprintf (outf, ";; Insn is not within a basic block\n");
    2239                 :       6928 :               else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB)
    2240                 :          0 :                 fprintf (outf, ";; Insn is in multiple basic blocks\n");
    2241                 :            :             }
    2242                 :            : 
    2243                 :     142851 :           if (flags & TDF_DETAILS)
    2244                 :      18110 :             df_dump_insn_top (tmp_rtx, outf);
    2245                 :     142851 :           if (! (flags & TDF_SLIM))
    2246                 :     142341 :             print_rtl_single (outf, tmp_rtx);
    2247                 :            :           else
    2248                 :        510 :             dump_insn_slim (outf, tmp_rtx);
    2249                 :     142851 :           if (flags & TDF_DETAILS)
    2250                 :      18110 :             df_dump_insn_bottom (tmp_rtx, outf);
    2251                 :            : 
    2252                 :     142851 :           bb = end[INSN_UID (tmp_rtx)];
    2253                 :     142851 :           if (bb != NULL)
    2254                 :            :             {
    2255                 :      16536 :               if (flags & TDF_BLOCKS)
    2256                 :            :                 {
    2257                 :        957 :                   dump_bb_info (outf, bb, 0, dump_flags, false, true);
    2258                 :        957 :                   if (df && (flags & TDF_DETAILS))
    2259                 :        578 :                     df_dump_bottom (bb, outf);
    2260                 :        957 :                   putc ('\n', outf);
    2261                 :            :                 }
    2262                 :            :               /* Emit a hint if the fallthrough target of current basic block
    2263                 :            :                  isn't the one placed right next.  */
    2264                 :     158305 :               else if (EDGE_COUNT (bb->succs) > 0)
    2265                 :            :                 {
    2266                 :      15454 :                   gcc_assert (BB_END (bb) == tmp_rtx);
    2267                 :      15454 :                   const rtx_insn *ninsn = NEXT_INSN (tmp_rtx);
    2268                 :            :                   /* Bypass intervening deleted-insn notes and debug insns.  */
    2269                 :      18965 :                   while (ninsn
    2270                 :      16648 :                          && !NONDEBUG_INSN_P (ninsn)
    2271                 :      35613 :                          && !start[INSN_UID (ninsn)])
    2272                 :       3511 :                     ninsn = NEXT_INSN (ninsn);
    2273                 :      15454 :                   edge e = find_fallthru_edge (bb->succs);
    2274                 :      15454 :                   if (e && ninsn)
    2275                 :            :                     {
    2276                 :      11399 :                       basic_block dest = e->dest;
    2277                 :      11399 :                       if (start[INSN_UID (ninsn)] != dest)
    2278                 :       2120 :                         fprintf (outf, "%s      ; pc falls through to BB %d\n",
    2279                 :            :                                  print_rtx_head, dest->index);
    2280                 :            :                     }
    2281                 :            :                 }
    2282                 :            :             }
    2283                 :            :         }
    2284                 :            : 
    2285                 :       3519 :       free (start);
    2286                 :       3519 :       free (end);
    2287                 :       3519 :       free (in_bb_p);
    2288                 :            :     }
    2289                 :       3519 : }
    2290                 :            : 
    2291                 :            : /* Update the branch probability of BB if a REG_BR_PROB is present.  */
    2292                 :            : 
    2293                 :            : void
    2294                 :    5880220 : update_br_prob_note (basic_block bb)
    2295                 :            : {
    2296                 :    5880220 :   rtx note;
    2297                 :    5880220 :   note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX);
    2298                 :    5880220 :   if (!JUMP_P (BB_END (bb)) || !BRANCH_EDGE (bb)->probability.initialized_p ())
    2299                 :            :     {
    2300                 :     163293 :       if (note)
    2301                 :            :         {
    2302                 :         50 :           rtx *note_link, this_rtx;
    2303                 :            : 
    2304                 :         50 :           note_link = &REG_NOTES (BB_END (bb));
    2305                 :        100 :           for (this_rtx = *note_link; this_rtx; this_rtx = XEXP (this_rtx, 1))
    2306                 :        100 :             if (this_rtx == note)
    2307                 :            :               {
    2308                 :         50 :                 *note_link = XEXP (this_rtx, 1);
    2309                 :         50 :                 break;
    2310                 :            :               }
    2311                 :            :         }
    2312                 :     163293 :       return;
    2313                 :            :     }
    2314                 :    5716920 :   if (!note
    2315                 :    5716920 :       || XINT (note, 0) == BRANCH_EDGE (bb)->probability.to_reg_br_prob_note ())
    2316                 :            :     return;
    2317                 :      94551 :   XINT (note, 0) = BRANCH_EDGE (bb)->probability.to_reg_br_prob_note ();
    2318                 :            : }
    2319                 :            : 
    2320                 :            : /* Get the last insn associated with block BB (that includes barriers and
    2321                 :            :    tablejumps after BB).  */
    2322                 :            : rtx_insn *
    2323                 :    4052650 : get_last_bb_insn (basic_block bb)
    2324                 :            : {
    2325                 :    4052650 :   rtx_jump_table_data *table;
    2326                 :    4052650 :   rtx_insn *tmp;
    2327                 :    4052650 :   rtx_insn *end = BB_END (bb);
    2328                 :            : 
    2329                 :            :   /* Include any jump table following the basic block.  */
    2330                 :    4052650 :   if (tablejump_p (end, NULL, &table))
    2331                 :          2 :     end = table;
    2332                 :            : 
    2333                 :            :   /* Include any barriers that may follow the basic block.  */
    2334                 :    4052650 :   tmp = next_nonnote_nondebug_insn_bb (end);
    2335                 :    4384410 :   while (tmp && BARRIER_P (tmp))
    2336                 :            :     {
    2337                 :     331760 :       end = tmp;
    2338                 :     331760 :       tmp = next_nonnote_nondebug_insn_bb (end);
    2339                 :            :     }
    2340                 :            : 
    2341                 :    4052650 :   return end;
    2342                 :            : }
    2343                 :            : 
    2344                 :            : /* Add all BBs reachable from entry via hot paths into the SET.  */
    2345                 :            : 
    2346                 :            : void
    2347                 :     415630 : find_bbs_reachable_by_hot_paths (hash_set<basic_block> *set)
    2348                 :            : {
    2349                 :     415630 :   auto_vec<basic_block, 64> worklist;
    2350                 :            : 
    2351                 :     415630 :   set->add (ENTRY_BLOCK_PTR_FOR_FN (cfun));
    2352                 :     415630 :   worklist.safe_push (ENTRY_BLOCK_PTR_FOR_FN (cfun));
    2353                 :            : 
    2354                 :   10177900 :   while (worklist.length () > 0)
    2355                 :            :     {
    2356                 :    9762310 :       basic_block bb = worklist.pop ();
    2357                 :    9762310 :       edge_iterator ei;
    2358                 :    9762310 :       edge e;
    2359                 :            : 
    2360                 :   24871900 :       FOR_EACH_EDGE (e, ei, bb->succs)
    2361                 :   15109600 :         if (BB_PARTITION (e->dest) != BB_COLD_PARTITION
    2362                 :   15109600 :             && !set->add (e->dest))
    2363                 :    9346680 :           worklist.safe_push (e->dest);
    2364                 :            :     }
    2365                 :     415630 : }
    2366                 :            : 
    2367                 :            : /* Sanity check partition hotness to ensure that basic blocks in
    2368                 :            :    the cold partition don't dominate basic blocks in the hot partition.
    2369                 :            :    If FLAG_ONLY is true, report violations as errors. Otherwise
    2370                 :            :    re-mark the dominated blocks as cold, since this is run after
    2371                 :            :    cfg optimizations that may make hot blocks previously reached
    2372                 :            :    by both hot and cold blocks now only reachable along cold paths.  */
    2373                 :            : 
    2374                 :            : static vec<basic_block>
    2375                 :     367330 : find_partition_fixes (bool flag_only)
    2376                 :            : {
    2377                 :     367330 :   basic_block bb;
    2378                 :     367330 :   vec<basic_block> bbs_to_fix = vNULL;
    2379                 :     367330 :   hash_set<basic_block> set;
    2380                 :            : 
    2381                 :            :   /* Callers check this.  */
    2382                 :     367330 :   gcc_checking_assert (crtl->has_bb_partition);
    2383                 :            : 
    2384                 :     367330 :   find_bbs_reachable_by_hot_paths (&set);
    2385                 :            : 
    2386                 :    9567850 :   FOR_EACH_BB_FN (bb, cfun)
    2387                 :    9200520 :     if (!set.contains (bb)
    2388                 :    9200520 :         && BB_PARTITION (bb) != BB_COLD_PARTITION)
    2389                 :            :       {
    2390                 :         18 :         if (flag_only)
    2391                 :          0 :           error ("non-cold basic block %d reachable only "
    2392                 :            :                  "by paths crossing the cold partition", bb->index);
    2393                 :            :         else
    2394                 :         18 :           BB_SET_PARTITION (bb, BB_COLD_PARTITION);
    2395                 :         18 :         bbs_to_fix.safe_push (bb);
    2396                 :            :       }
    2397                 :            : 
    2398                 :     367330 :   return bbs_to_fix;
    2399                 :            : }
    2400                 :            : 
    2401                 :            : /* Perform cleanup on the hot/cold bb partitioning after optimization
    2402                 :            :    passes that modify the cfg.  */
    2403                 :            : 
    2404                 :            : void
    2405                 :    8371360 : fixup_partitions (void)
    2406                 :            : {
    2407                 :    8371360 :   basic_block bb;
    2408                 :            : 
    2409                 :    8371360 :   if (!crtl->has_bb_partition)
    2410                 :    8371360 :     return;
    2411                 :            : 
    2412                 :            :   /* Delete any blocks that became unreachable and weren't
    2413                 :            :      already cleaned up, for example during edge forwarding
    2414                 :            :      and convert_jumps_to_returns. This will expose more
    2415                 :            :      opportunities for fixing the partition boundaries here.
    2416                 :            :      Also, the calculation of the dominance graph during verification
    2417                 :            :      will assert if there are unreachable nodes.  */
    2418                 :     272258 :   delete_unreachable_blocks ();
    2419                 :            : 
    2420                 :            :   /* If there are partitions, do a sanity check on them: A basic block in
    2421                 :            :      a cold partition cannot dominate a basic block in a hot partition.
    2422                 :            :      Fixup any that now violate this requirement, as a result of edge
    2423                 :            :      forwarding and unreachable block deletion.  */
    2424                 :     272258 :   vec<basic_block> bbs_to_fix = find_partition_fixes (false);
    2425                 :            : 
    2426                 :            :   /* Do the partition fixup after all necessary blocks have been converted to
    2427                 :            :      cold, so that we only update the region crossings the minimum number of
    2428                 :            :      places, which can require forcing edges to be non fallthru.  */
    2429                 :     272276 :   while (! bbs_to_fix.is_empty ())
    2430                 :            :     {
    2431                 :         18 :       bb = bbs_to_fix.pop ();
    2432                 :         18 :       fixup_new_cold_bb (bb);
    2433                 :            :     }
    2434                 :            : }
    2435                 :            : 
    2436                 :            : /* Verify, in the basic block chain, that there is at most one switch
    2437                 :            :    between hot/cold partitions. This condition will not be true until
    2438                 :            :    after reorder_basic_blocks is called.  */
    2439                 :            : 
    2440                 :            : static int
    2441                 :   37043700 : verify_hot_cold_block_grouping (void)
    2442                 :            : {
    2443                 :   37043700 :   basic_block bb;
    2444                 :   37043700 :   int err = 0;
    2445                 :   37043700 :   bool switched_sections = false;
    2446                 :   37043700 :   int current_partition = BB_UNPARTITIONED;
    2447                 :            : 
    2448                 :            :   /* Even after bb reordering is complete, we go into cfglayout mode
    2449                 :            :      again (in compgoto). Ensure we don't call this before going back
    2450                 :            :      into linearized RTL when any layout fixes would have been committed.  */
    2451                 :   37043700 :   if (!crtl->bb_reorder_complete
    2452                 :   37043700 :       || current_ir_type () != IR_RTL_CFGRTL)
    2453                 :   32435700 :     return err;
    2454                 :            : 
    2455                 :   75541400 :   FOR_EACH_BB_FN (bb, cfun)
    2456                 :            :     {
    2457                 :   70933400 :       if (current_partition != BB_UNPARTITIONED
    2458                 :   26864300 :           && BB_PARTITION (bb) != current_partition)
    2459                 :            :         {
    2460                 :     494127 :           if (switched_sections)
    2461                 :            :             {
    2462                 :          0 :               error ("multiple hot/cold transitions found (bb %i)",
    2463                 :            :                      bb->index);
    2464                 :          0 :               err = 1;
    2465                 :            :             }
    2466                 :            :           else
    2467                 :            :             switched_sections = true;
    2468                 :            : 
    2469                 :     494127 :           if (!crtl->has_bb_partition)
    2470                 :          0 :             error ("partition found but function partition flag not set");
    2471                 :            :         }
    2472                 :   70933400 :       current_partition = BB_PARTITION (bb);
    2473                 :            :     }
    2474                 :            : 
    2475                 :            :   return err;
    2476                 :            : }
    2477                 :            : 
    2478                 :            : 
    2479                 :            : /* Perform several checks on the edges out of each block, such as
    2480                 :            :    the consistency of the branch probabilities, the correctness
    2481                 :            :    of hot/cold partition crossing edges, and the number of expected
    2482                 :            :    successor edges.  Also verify that the dominance relationship
    2483                 :            :    between hot/cold blocks is sane.  */
    2484                 :            : 
    2485                 :            : static int
    2486                 :   58592500 : rtl_verify_edges (void)
    2487                 :            : {
    2488                 :   58592500 :   int err = 0;
    2489                 :   58592500 :   basic_block bb;
    2490                 :            : 
    2491                 :  674190000 :   FOR_EACH_BB_REVERSE_FN (bb, cfun)
    2492                 :            :     {
    2493                 :  615597000 :       int n_fallthru = 0, n_branch = 0, n_abnormal_call = 0, n_sibcall = 0;
    2494                 :  615597000 :       int n_eh = 0, n_abnormal = 0;
    2495                 :  615597000 :       edge e, fallthru = NULL;
    2496                 :  615597000 :       edge_iterator ei;
    2497                 :  615597000 :       rtx note;
    2498                 :  615597000 :       bool has_crossing_edge = false;
    2499                 :            : 
    2500                 :  615597000 :       if (JUMP_P (BB_END (bb))
    2501                 :  356068000 :           && (note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX))
    2502                 :  244920000 :           && EDGE_COUNT (bb->succs) >= 2
    2503                 :  860517000 :           && any_condjump_p (BB_END (bb)))
    2504                 :            :         {
    2505                 :  244920000 :           if (!BRANCH_EDGE (bb)->probability.initialized_p ())
    2506                 :            :             {
    2507                 :     128480 :               if (profile_status_for_fn (cfun) != PROFILE_ABSENT)
    2508                 :            :                 {
    2509                 :          0 :                   error ("verify_flow_info: "
    2510                 :            :                          "REG_BR_PROB is set but cfg probability is not");
    2511                 :          0 :                   err = 1;
    2512                 :            :                 }
    2513                 :            :             }
    2514                 :  244791000 :           else if (XINT (note, 0)
    2515                 :  244791000 :                    != BRANCH_EDGE (bb)->probability.to_reg_br_prob_note ()
    2516                 :  244791000 :                    && profile_status_for_fn (cfun) != PROFILE_ABSENT)
    2517                 :            :             {
    2518                 :          0 :               error ("verify_flow_info: REG_BR_PROB does not match cfg %i %i",
    2519                 :            :                      XINT (note, 0),
    2520                 :          0 :                      BRANCH_EDGE (bb)->probability.to_reg_br_prob_note ());
    2521                 :          0 :               err = 1;
    2522                 :            :             }
    2523                 :            :         }
    2524                 :            : 
    2525                 : 1509270000 :       FOR_EACH_EDGE (e, ei, bb->succs)
    2526                 :            :         {
    2527                 :  893672000 :           bool is_crossing;
    2528                 :            : 
    2529                 :  893672000 :           if (e->flags & EDGE_FALLTHRU)
    2530                 :  487762000 :             n_fallthru++, fallthru = e;
    2531                 :            : 
    2532                 : 1787340000 :           is_crossing = (BB_PARTITION (e->src) != BB_PARTITION (e->dest)
    2533                 :   23766800 :                          && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
    2534                 :  917439000 :                          && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun));
    2535                 :  893672000 :           has_crossing_edge |= is_crossing;
    2536                 :  893672000 :           if (e->flags & EDGE_CROSSING)
    2537                 :            :             {
    2538                 :   14078200 :               if (!is_crossing)
    2539                 :            :                 {
    2540                 :          0 :                   error ("EDGE_CROSSING incorrectly set across same section");
    2541                 :          0 :                   err = 1;
    2542                 :            :                 }
    2543                 :   14078200 :               if (e->flags & EDGE_FALLTHRU)
    2544                 :            :                 {
    2545                 :          0 :                   error ("fallthru edge crosses section boundary in bb %i",
    2546                 :          0 :                          e->src->index);
    2547                 :          0 :                   err = 1;
    2548                 :            :                 }
    2549                 :   14078200 :               if (e->flags & EDGE_EH)
    2550                 :            :                 {
    2551                 :          0 :                   error ("EH edge crosses section boundary in bb %i",
    2552                 :          0 :                          e->src->index);
    2553                 :          0 :                   err = 1;
    2554                 :            :                 }
    2555                 :   14078200 :               if (JUMP_P (BB_END (bb)) && !CROSSING_JUMP_P (BB_END (bb)))
    2556                 :            :                 {
    2557                 :          0 :                   error ("No region crossing jump at section boundary in bb %i",
    2558                 :            :                          bb->index);
    2559                 :          0 :                   err = 1;
    2560                 :            :                 }
    2561                 :            :             }
    2562                 :  879594000 :           else if (is_crossing)
    2563                 :            :             {
    2564                 :          0 :               error ("EDGE_CROSSING missing across section boundary");
    2565                 :          0 :               err = 1;
    2566                 :            :             }
    2567                 :            : 
    2568                 :  893672000 :           if ((e->flags & ~(EDGE_DFS_BACK
    2569                 :            :                             | EDGE_CAN_FALLTHRU
    2570                 :            :                             | EDGE_IRREDUCIBLE_LOOP
    2571                 :            :                             | EDGE_LOOP_EXIT
    2572                 :            :                             | EDGE_CROSSING
    2573                 :            :                             | EDGE_PRESERVE)) == 0)
    2574                 :  359258000 :             n_branch++;
    2575                 :            : 
    2576                 :  893672000 :           if (e->flags & EDGE_ABNORMAL_CALL)
    2577                 :   32878600 :             n_abnormal_call++;
    2578                 :            : 
    2579                 :  893672000 :           if (e->flags & EDGE_SIBCALL)
    2580                 :    6700720 :             n_sibcall++;
    2581                 :            : 
    2582                 :  893672000 :           if (e->flags & EDGE_EH)
    2583                 :   38315100 :             n_eh++;
    2584                 :            : 
    2585                 :  893672000 :           if (e->flags & EDGE_ABNORMAL)
    2586                 :   46382700 :             n_abnormal++;
    2587                 :            :         }
    2588                 :            : 
    2589                 :  615597000 :       if (!has_crossing_edge
    2590                 :  601528000 :           && JUMP_P (BB_END (bb))
    2591                 :  957603000 :           && CROSSING_JUMP_P (BB_END (bb)))
    2592                 :            :         {
    2593                 :          0 :           print_rtl_with_bb (stderr, get_insns (), TDF_BLOCKS | TDF_DETAILS);
    2594                 :          0 :           error ("Region crossing jump across same section in bb %i",
    2595                 :            :                  bb->index);
    2596                 :          0 :           err = 1;
    2597                 :            :         }
    2598                 :            : 
    2599                 :  615597000 :       if (n_eh && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX))
    2600                 :            :         {
    2601                 :          0 :           error ("missing REG_EH_REGION note at the end of bb %i", bb->index);
    2602                 :          0 :           err = 1;
    2603                 :            :         }
    2604                 :  615597000 :       if (n_eh > 1)
    2605                 :            :         {
    2606                 :          0 :           error ("too many exception handling edges in bb %i", bb->index);
    2607                 :          0 :           err = 1;
    2608                 :            :         }
    2609                 :  615597000 :       if (n_branch
    2610                 :  615597000 :           && (!JUMP_P (BB_END (bb))
    2611                 :  355989000 :               || (n_branch > 1 && (any_uncondjump_p (BB_END (bb))
    2612                 :     474051 :                                    || any_condjump_p (BB_END (bb))))))
    2613                 :            :         {
    2614                 :          0 :           error ("too many outgoing branch edges from bb %i", bb->index);
    2615                 :          0 :           err = 1;
    2616                 :            :         }
    2617                 :  615597000 :       if (n_fallthru && any_uncondjump_p (BB_END (bb)))
    2618                 :            :         {
    2619                 :          0 :           error ("fallthru edge after unconditional jump in bb %i", bb->index);
    2620                 :          0 :           err = 1;
    2621                 :            :         }
    2622                 :  615597000 :       if (n_branch != 1 && any_uncondjump_p (BB_END (bb)))
    2623                 :            :         {
    2624                 :          0 :           error ("wrong number of branch edges after unconditional jump"
    2625                 :            :                  " in bb %i", bb->index);
    2626                 :          0 :           err = 1;
    2627                 :            :         }
    2628                 :  260082000 :       if (n_branch != 1 && any_condjump_p (BB_END (bb))
    2629                 :  615598000 :           && JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest))
    2630                 :            :         {
    2631                 :          0 :           error ("wrong amount of branch edges after conditional jump"
    2632                 :            :                  " in bb %i", bb->index);
    2633                 :          0 :           err = 1;
    2634                 :            :         }
    2635                 :  615597000 :       if (n_abnormal_call && !CALL_P (BB_END (bb)))
    2636                 :            :         {
    2637                 :          0 :           error ("abnormal call edges for non-call insn in bb %i", bb->index);
    2638                 :          0 :           err = 1;
    2639                 :            :         }
    2640                 :  615597000 :       if (n_sibcall && !CALL_P (BB_END (bb)))
    2641                 :            :         {
    2642                 :          0 :           error ("sibcall edges for non-call insn in bb %i", bb->index);
    2643                 :          0 :           err = 1;
    2644                 :            :         }
    2645                 :  615597000 :       if (n_abnormal > n_eh
    2646                 :    6883450 :           && !(CALL_P (BB_END (bb))
    2647                 :    6867420 :                && n_abnormal == n_abnormal_call + n_sibcall)
    2648                 :  615613000 :           && (!JUMP_P (BB_END (bb))
    2649                 :      16033 :               || any_condjump_p (BB_END (bb))
    2650                 :      16033 :               || any_uncondjump_p (BB_END (bb))))
    2651                 :            :         {
    2652                 :          0 :           error ("abnormal edges for no purpose in bb %i", bb->index);
    2653                 :          0 :           err = 1;
    2654                 :            :         }
    2655                 :            : 
    2656                 :  615597000 :       int has_eh = -1;
    2657                 : 1505650000 :       FOR_EACH_EDGE (e, ei, bb->preds)
    2658                 :            :         {
    2659                 :  890049000 :           if (has_eh == -1)
    2660                 :  615513000 :             has_eh = (e->flags & EDGE_EH);
    2661                 :  890049000 :           if ((e->flags & EDGE_EH) == has_eh)
    2662                 :  890049000 :             continue;
    2663                 :          0 :           error ("EH incoming edge mixed with non-EH incoming edges "
    2664                 :            :                  "in bb %i", bb->index);
    2665                 :          0 :           err = 1;
    2666                 :          0 :           break;
    2667                 :            :         }
    2668                 :            :     }
    2669                 :            : 
    2670                 :            :   /* If there are partitions, do a sanity check on them: A basic block in
    2671                 :            :      a cold partition cannot dominate a basic block in a hot partition.  */
    2672                 :    1978770 :   if (crtl->has_bb_partition && !err
    2673                 :   60571300 :       && current_ir_type () == IR_RTL_CFGLAYOUT)
    2674                 :            :     {
    2675                 :      95072 :       vec<basic_block> bbs_to_fix = find_partition_fixes (true);
    2676                 :      95072 :       err = !bbs_to_fix.is_empty ();
    2677                 :            :     }
    2678                 :            : 
    2679                 :            :   /* Clean up.  */
    2680                 :   58592500 :   return err;
    2681                 :            : }
    2682                 :            : 
    2683                 :            : /* Checks on the instructions within blocks. Currently checks that each
    2684                 :            :    block starts with a basic block note, and that basic block notes and
    2685                 :            :    control flow jumps are not found in the middle of the block.  */
    2686                 :            : 
    2687                 :            : static int
    2688                 :   58592500 : rtl_verify_bb_insns (void)
    2689                 :            : {
    2690                 :   58592500 :   rtx_insn *x;
    2691                 :   58592500 :   int err = 0;
    2692                 :   58592500 :   basic_block bb;
    2693                 :            : 
    2694                 :  674190000 :   FOR_EACH_BB_REVERSE_FN (bb, cfun)
    2695                 :            :     {
    2696                 :            :       /* Now check the header of basic
    2697                 :            :          block.  It ought to contain optional CODE_LABEL followed
    2698                 :            :          by NOTE_BASIC_BLOCK.  */
    2699                 :  615597000 :       x = BB_HEAD (bb);
    2700                 :  615597000 :       if (LABEL_P (x))
    2701                 :            :         {
    2702                 :  293951000 :           if (BB_END (bb) == x)
    2703                 :            :             {
    2704                 :          0 :               error ("NOTE_INSN_BASIC_BLOCK is missing for block %d",
    2705                 :            :                      bb->index);
    2706                 :          0 :               err = 1;
    2707                 :            :             }
    2708                 :            : 
    2709                 :  293951000 :           x = NEXT_INSN (x);
    2710                 :            :         }
    2711                 :            : 
    2712                 :  615597000 :       if (!NOTE_INSN_BASIC_BLOCK_P (x) || NOTE_BASIC_BLOCK (x) != bb)
    2713                 :            :         {
    2714                 :          0 :           error ("NOTE_INSN_BASIC_BLOCK is missing for block %d",
    2715                 :            :                  bb->index);
    2716                 :          0 :           err = 1;
    2717                 :            :         }
    2718                 :            : 
    2719                 :  615597000 :       if (BB_END (bb) == x)
    2720                 :            :         /* Do checks for empty blocks here.  */
    2721                 :            :         ;
    2722                 :            :       else
    2723                 :11577800000 :         for (x = NEXT_INSN (x); x; x = NEXT_INSN (x))
    2724                 :            :           {
    2725                 : 6091130000 :             if (NOTE_INSN_BASIC_BLOCK_P (x))
    2726                 :            :               {
    2727                 :          0 :                 error ("NOTE_INSN_BASIC_BLOCK %d in middle of basic block %d",
    2728                 :          0 :                        INSN_UID (x), bb->index);
    2729                 :          0 :                 err = 1;
    2730                 :            :               }
    2731                 :            : 
    2732                 : 6091130000 :             if (x == BB_END (bb))
    2733                 :            :               break;
    2734                 :            : 
    2735                 : 5486670000 :             if (control_flow_insn_p (x))
    2736                 :            :               {
    2737                 :          0 :                 error ("in basic block %d:", bb->index);
    2738                 :          0 :                 fatal_insn ("flow control insn inside a basic block", x);
    2739                 :            :               }
    2740                 :            :           }
    2741                 :            :     }
    2742                 :            : 
    2743                 :            :   /* Clean up.  */
    2744                 :   58592500 :   return err;
    2745                 :            : }
    2746                 :            : 
    2747                 :            : /* Verify that block pointers for instructions in basic blocks, headers and
    2748                 :            :    footers are set appropriately.  */
    2749                 :            : 
    2750                 :            : static int
    2751                 :   58592500 : rtl_verify_bb_pointers (void)
    2752                 :            : {
    2753                 :   58592500 :   int err = 0;
    2754                 :   58592500 :   basic_block bb;
    2755                 :            : 
    2756                 :            :   /* Check the general integrity of the basic blocks.  */
    2757                 :  674190000 :   FOR_EACH_BB_REVERSE_FN (bb, cfun)
    2758                 :            :     {
    2759                 :  615597000 :       rtx_insn *insn;
    2760                 :            : 
    2761                 :  615597000 :       if (!(bb->flags & BB_RTL))
    2762                 :            :         {
    2763                 :          0 :           error ("BB_RTL flag not set for block %d", bb->index);
    2764                 :          0 :           err = 1;
    2765                 :            :         }
    2766                 :            : 
    2767                 :14617000000 :       FOR_BB_INSNS (bb, insn)
    2768                 : 7000680000 :         if (BLOCK_FOR_INSN (insn) != bb)
    2769                 :            :           {
    2770                 :          0 :             error ("insn %d basic block pointer is %d, should be %d",
    2771                 :          0 :                    INSN_UID (insn),
    2772                 :          0 :                    BLOCK_FOR_INSN (insn) ? BLOCK_FOR_INSN (insn)->index : 0,
    2773                 :            :                    bb->index);
    2774                 :          0 :             err = 1;
    2775                 :            :           }
    2776                 :            : 
    2777                 :  615700000 :       for (insn = BB_HEADER (bb); insn; insn = NEXT_INSN (insn))
    2778                 :      51578 :         if (!BARRIER_P (insn)
    2779                 :      51578 :             && BLOCK_FOR_INSN (insn) != NULL)
    2780                 :            :           {
    2781                 :          0 :             error ("insn %d in header of bb %d has non-NULL basic block",
    2782                 :          0 :                    INSN_UID (insn), bb->index);
    2783                 :          0 :             err = 1;
    2784                 :            :           }
    2785                 :  651050000 :       for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn))
    2786                 :   17726200 :         if (!BARRIER_P (insn)
    2787                 :   17726200 :             && BLOCK_FOR_INSN (insn) != NULL)
    2788                 :            :           {
    2789                 :          0 :             error ("insn %d in footer of bb %d has non-NULL basic block",
    2790                 :          0 :                    INSN_UID (insn), bb->index);
    2791                 :          0 :             err = 1;
    2792                 :            :           }
    2793                 :            :     }
    2794                 :            : 
    2795                 :            :   /* Clean up.  */
    2796                 :   58592500 :   return err;
    2797                 :            : }
    2798                 :            : 
    2799                 :            : /* Verify the CFG and RTL consistency common for both underlying RTL and
    2800                 :            :    cfglayout RTL.
    2801                 :            : 
    2802                 :            :    Currently it does following checks:
    2803                 :            : 
    2804                 :            :    - overlapping of basic blocks
    2805                 :            :    - insns with wrong BLOCK_FOR_INSN pointers
    2806                 :            :    - headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note)
    2807                 :            :    - tails of basic blocks (ensure that boundary is necessary)
    2808                 :            :    - scans body of the basic block for JUMP_INSN, CODE_LABEL
    2809                 :            :      and NOTE_INSN_BASIC_BLOCK
    2810                 :            :    - verify that no fall_thru edge crosses hot/cold partition boundaries
    2811                 :            :    - verify that there are no pending RTL branch predictions
    2812                 :            :    - verify that hot blocks are not dominated by cold blocks
    2813                 :            : 
    2814                 :            :    In future it can be extended check a lot of other stuff as well
    2815                 :            :    (reachability of basic blocks, life information, etc. etc.).  */
    2816                 :            : 
    2817                 :            : static int
    2818                 :   58592500 : rtl_verify_flow_info_1 (void)
    2819                 :            : {
    2820                 :   58592500 :   int err = 0;
    2821                 :            : 
    2822                 :   58592500 :   err |= rtl_verify_bb_pointers ();
    2823                 :            : 
    2824                 :   58592500 :   err |= rtl_verify_bb_insns ();
    2825                 :            : 
    2826                 :   58592500 :   err |= rtl_verify_edges ();
    2827                 :            : 
    2828                 :   58592500 :   return err;
    2829                 :            : }
    2830                 :            : 
    2831                 :            : /* Walk the instruction chain and verify that bb head/end pointers
    2832                 :            :   are correct, and that instructions are in exactly one bb and have
    2833                 :            :   correct block pointers.  */
    2834                 :            : 
    2835                 :            : static int
    2836                 :   37043700 : rtl_verify_bb_insn_chain (void)
    2837                 :            : {
    2838                 :   37043700 :   basic_block bb;
    2839                 :   37043700 :   int err = 0;
    2840                 :   37043700 :   rtx_insn *x;
    2841                 :   37043700 :   rtx_insn *last_head = get_last_insn ();
    2842                 :   37043700 :   basic_block *bb_info;
    2843                 :   37043700 :   const int max_uid = get_max_uid ();
    2844                 :            : 
    2845                 :   37043700 :   bb_info = XCNEWVEC (basic_block, max_uid);
    2846                 :            : 
    2847                 :  414991000 :   FOR_EACH_BB_REVERSE_FN (bb, cfun)
    2848                 :            :     {
    2849                 :  377947000 :       rtx_insn *head = BB_HEAD (bb);
    2850                 :  377947000 :       rtx_insn *end = BB_END (bb);
    2851                 :            : 
    2852                 :  672085000 :       for (x = last_head; x != NULL_RTX; x = PREV_INSN (x))
    2853                 :            :         {
    2854                 :            :           /* Verify the end of the basic block is in the INSN chain.  */
    2855                 :  525016000 :           if (x == end)
    2856                 :            :             break;
    2857                 :            : 
    2858                 :            :             /* And that the code outside of basic blocks has NULL bb field.  */
    2859                 :  147069000 :           if (!BARRIER_P (x)
    2860                 :  147069000 :               && BLOCK_FOR_INSN (x) != NULL)
    2861                 :            :             {
    2862                 :          0 :               error ("insn %d outside of basic blocks has non-NULL bb field",
    2863                 :          0 :                      INSN_UID (x));
    2864                 :          0 :               err = 1;
    2865                 :            :             }
    2866                 :            :         }
    2867                 :            : 
    2868                 :  377947000 :       if (!x)
    2869                 :            :         {
    2870                 :          0 :           error ("end insn %d for block %d not found in the insn stream",
    2871                 :          0 :                  INSN_UID (end), bb->index);
    2872                 :          0 :           err = 1;
    2873                 :            :         }
    2874                 :            : 
    2875                 :            :       /* Work backwards from the end to the head of the basic block
    2876                 :            :          to verify the head is in the RTL chain.  */
    2877                 : 8200050000 :       for (; x != NULL_RTX; x = PREV_INSN (x))
    2878                 :            :         {
    2879                 :            :           /* While walking over the insn chain, verify insns appear
    2880                 :            :              in only one basic block.  */
    2881                 : 4289000000 :           if (bb_info[INSN_UID (x)] != NULL)
    2882                 :            :             {
    2883                 :          0 :               error ("insn %d is in multiple basic blocks (%d and %d)",
    2884                 :          0 :                      INSN_UID (x), bb->index, bb_info[INSN_UID (x)]->index);
    2885                 :          0 :               err = 1;
    2886                 :            :             }
    2887                 :            : 
    2888                 : 4289000000 :           bb_info[INSN_UID (x)] = bb;
    2889                 :            : 
    2890                 : 4289000000 :           if (x == head)
    2891                 :            :             break;
    2892                 :            :         }
    2893                 :  377947000 :       if (!x)
    2894                 :            :         {
    2895                 :          0 :           error ("head insn %d for block %d not found in the insn stream",
    2896                 :          0 :                  INSN_UID (head), bb->index);
    2897                 :          0 :           err = 1;
    2898                 :            :         }
    2899                 :            : 
    2900                 :  377947000 :       last_head = PREV_INSN (x);
    2901                 :            :     }
    2902                 :            : 
    2903                 :   74799000 :   for (x = last_head; x != NULL_RTX; x = PREV_INSN (x))
    2904                 :            :     {
    2905                 :            :       /* Check that the code before the first basic block has NULL
    2906                 :            :          bb field.  */
    2907                 :   37755300 :       if (!BARRIER_P (x)
    2908                 :   37755300 :           && BLOCK_FOR_INSN (x) != NULL)
    2909                 :            :         {
    2910                 :          0 :           error ("insn %d outside of basic blocks has non-NULL bb field",
    2911                 :          0 :                  INSN_UID (x));
    2912                 :          0 :           err = 1;
    2913                 :            :         }
    2914                 :            :     }
    2915                 :   37043700 :   free (bb_info);
    2916                 :            : 
    2917                 :   37043700 :   return err;
    2918                 :            : }
    2919                 :            : 
    2920                 :            : /* Verify that fallthru edges point to adjacent blocks in layout order and
    2921                 :            :    that barriers exist after non-fallthru blocks.  */
    2922                 :            : 
    2923                 :            : static int
    2924                 :   37043700 : rtl_verify_fallthru (void)
    2925                 :            : {
    2926                 :   37043700 :   basic_block bb;
    2927                 :   37043700 :   int err = 0;
    2928                 :            : 
    2929                 :  414991000 :   FOR_EACH_BB_REVERSE_FN (bb, cfun)
    2930                 :            :     {
    2931                 :  377947000 :       edge e;
    2932                 :            : 
    2933                 :  377947000 :       e = find_fallthru_edge (bb->succs);
    2934                 :  377947000 :       if (!e)
    2935                 :            :         {
    2936                 :  110481000 :           rtx_insn *insn;
    2937                 :            : 
    2938                 :            :           /* Ensure existence of barrier in BB with no fallthru edges.  */
    2939                 :  110806000 :           for (insn = NEXT_INSN (BB_END (bb)); ; insn = NEXT_INSN (insn))
    2940                 :            :             {
    2941                 :  110806000 :               if (!insn || NOTE_INSN_BASIC_BLOCK_P (insn))
    2942                 :            :                 {
    2943                 :          0 :                   error ("missing barrier after block %i", bb->index);
    2944                 :          0 :                   err = 1;
    2945                 :          0 :                   break;
    2946                 :            :                 }
    2947                 :  110806000 :               if (BARRIER_P (insn))
    2948                 :            :                 break;
    2949                 :            :             }
    2950                 :            :         }
    2951                 :  267466000 :       else if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
    2952                 :  267466000 :                && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
    2953                 :            :         {
    2954                 :  249367000 :           rtx_insn *insn;
    2955                 :            : 
    2956                 :  249367000 :           if (e->src->next_bb != e->dest)
    2957                 :            :             {
    2958                 :          0 :               error
    2959                 :          0 :                 ("verify_flow_info: Incorrect blocks for fallthru %i->%i",
    2960                 :            :                  e->src->index, e->dest->index);
    2961                 :          0 :               err = 1;
    2962                 :            :             }
    2963                 :            :           else
    2964                 :  252938000 :             for (insn = NEXT_INSN (BB_END (e->src)); insn != BB_HEAD (e->dest);
    2965                 :    3571530 :                  insn = NEXT_INSN (insn))
    2966                 :    3571530 :               if (BARRIER_P (insn) || NONDEBUG_INSN_P (insn))
    2967                 :            :                 {
    2968                 :          0 :                   error ("verify_flow_info: Incorrect fallthru %i->%i",
    2969                 :            :                          e->src->index, e->dest->index);
    2970                 :          0 :                   fatal_insn ("wrong insn in the fallthru edge", insn);
    2971                 :            :                   err = 1;
    2972                 :            :                 }
    2973                 :            :         }
    2974                 :            :     }
    2975                 :            : 
    2976                 :   37043700 :    return err;
    2977                 :            : }
    2978                 :            : 
    2979                 :            : /* Verify that blocks are laid out in consecutive order. While walking the
    2980                 :            :    instructions, verify that all expected instructions are inside the basic
    2981                 :            :    blocks, and that all returns are followed by barriers.  */
    2982                 :            : 
    2983                 :            : static int
    2984                 :   37043700 : rtl_verify_bb_layout (void)
    2985                 :            : {
    2986                 :   37043700 :   basic_block bb;
    2987                 :   37043700 :   int err = 0;
    2988                 :   37043700 :   rtx_insn *x, *y;
    2989                 :   37043700 :   int num_bb_notes;
    2990                 :   37043700 :   rtx_insn * const rtx_first = get_insns ();
    2991                 :   37043700 :   basic_block last_bb_seen = ENTRY_BLOCK_PTR_FOR_FN (cfun), curr_bb = NULL;
    2992                 :            : 
    2993                 :   37043700 :   num_bb_notes = 0;
    2994                 :            : 
    2995                 : 8984010000 :   for (x = rtx_first; x; x = NEXT_INSN (x))
    2996                 :            :     {
    2997                 : 4473480000 :       if (NOTE_INSN_BASIC_BLOCK_P (x))
    2998                 :            :         {
    2999                 :  377947000 :           bb = NOTE_BASIC_BLOCK (x);
    3000                 :            : 
    3001                 :  377947000 :           num_bb_notes++;
    3002                 :  377947000 :           if (bb != last_bb_seen->next_bb)
    3003                 :          0 :             internal_error ("basic blocks not laid down consecutively");
    3004                 :            : 
    3005                 :            :           curr_bb = last_bb_seen = bb;
    3006                 :            :         }
    3007                 :            : 
    3008                 : 4473480000 :       if (!curr_bb)
    3009                 :            :         {
    3010                 :  362929000 :           switch (GET_CODE (x))
    3011                 :            :             {
    3012                 :            :             case BARRIER:
    3013                 :            :             case NOTE:
    3014                 :            :               break;
    3015                 :            : 
    3016                 :  178779000 :             case CODE_LABEL:
    3017                 :            :               /* An ADDR_VEC is placed outside any basic block.  */
    3018                 :  178779000 :               if (NEXT_INSN (x)
    3019                 :  178779000 :                   && JUMP_TABLE_DATA_P (NEXT_INSN (x)))
    3020                 : 4473480000 :                 x = NEXT_INSN (x);
    3021                 :            : 
    3022                 :            :               /* But in any case, non-deletable labels can appear anywhere.  */
    3023                 :            :               break;
    3024                 :            : 
    3025                 :          0 :             default:
    3026                 :          0 :               fatal_insn ("insn outside basic block", x);
    3027                 :            :             }
    3028                 :            :         }
    3029                 :            : 
    3030                 : 4473480000 :       if (JUMP_P (x)
    3031                 :  248464000 :           && returnjump_p (x) && ! condjump_p (x)
    3032                 : 4491100000 :           && ! ((y = next_nonnote_nondebug_insn (x))
    3033                 :   17613100 :                 && BARRIER_P (y)))
    3034                 :          0 :             fatal_insn ("return not followed by barrier", x);
    3035                 :            : 
    3036                 : 4473480000 :       if (curr_bb && x == BB_END (curr_bb))
    3037                 :  377947000 :         curr_bb = NULL;
    3038                 :            :     }
    3039                 :            : 
    3040                 :   37043700 :   if (num_bb_notes != n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS)
    3041                 :          0 :     internal_error
    3042                 :          0 :       ("number of bb notes in insn chain (%d) != n_basic_blocks (%d)",
    3043                 :            :        num_bb_notes, n_basic_blocks_for_fn (cfun));
    3044                 :            : 
    3045                 :   37043700 :    return err;
    3046                 :            : }
    3047                 :            : 
    3048                 :            : /* Verify the CFG and RTL consistency common for both underlying RTL and
    3049                 :            :    cfglayout RTL, plus consistency checks specific to linearized RTL mode.
    3050                 :            : 
    3051                 :            :    Currently it does following checks:
    3052                 :            :    - all checks of rtl_verify_flow_info_1
    3053                 :            :    - test head/end pointers
    3054                 :            :    - check that blocks are laid out in consecutive order
    3055                 :            :    - check that all insns are in the basic blocks
    3056                 :            :      (except the switch handling code, barriers and notes)
    3057                 :            :    - check that all returns are followed by barriers
    3058                 :            :    - check that all fallthru edge points to the adjacent blocks
    3059                 :            :    - verify that there is a single hot/cold partition boundary after bbro  */
    3060                 :            : 
    3061                 :            : static int
    3062                 :   37043700 : rtl_verify_flow_info (void)
    3063                 :            : {
    3064                 :   37043700 :   int err = 0;
    3065                 :            : 
    3066                 :   37043700 :   err |= rtl_verify_flow_info_1 ();
    3067                 :            : 
    3068                 :   37043700 :   err |= rtl_verify_bb_insn_chain ();
    3069                 :            : 
    3070                 :   37043700 :   err |= rtl_verify_fallthru ();
    3071                 :            : 
    3072                 :   37043700 :   err |= rtl_verify_bb_layout ();
    3073                 :            : 
    3074                 :   37043700 :   err |= verify_hot_cold_block_grouping ();
    3075                 :            : 
    3076                 :   37043700 :   return err;
    3077                 :            : }
    3078                 :            : 
    3079                 :            : /* Assume that the preceding pass has possibly eliminated jump instructions
    3080                 :            :    or converted the unconditional jumps.  Eliminate the edges from CFG.
    3081                 :            :    Return true if any edges are eliminated.  */
    3082                 :            : 
    3083                 :            : bool
    3084                 :   42900500 : purge_dead_edges (basic_block bb)
    3085                 :            : {
    3086                 :   42900500 :   edge e;
    3087                 :   42900500 :   rtx_insn *insn = BB_END (bb);
    3088                 :   42900500 :   rtx note;
    3089                 :   42900500 :   bool purged = false;
    3090                 :   42900500 :   bool found;
    3091                 :   42900500 :   edge_iterator ei;
    3092                 :            : 
    3093                 :   42900500 :   if (DEBUG_INSN_P (insn) && insn != BB_HEAD (bb))
    3094                 :    4591530 :     do
    3095                 :    4591530 :       insn = PREV_INSN (insn);
    3096                 :    4591530 :     while ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb));
    3097                 :            : 
    3098                 :            :   /* If this instruction cannot trap, remove REG_EH_REGION notes.  */
    3099                 :   42900500 :   if (NONJUMP_INSN_P (insn)
    3100                 :   42900500 :       && (note = find_reg_note (insn, REG_EH_REGION, NULL)))
    3101                 :            :     {
    3102                 :     744494 :       rtx eqnote;
    3103                 :            : 
    3104                 :     744494 :       if (! may_trap_p (PATTERN (insn))
    3105                 :     744494 :           || ((eqnote = find_reg_equal_equiv_note (insn))
    3106                 :         23 :               && ! may_trap_p (XEXP (eqnote, 0))))
    3107                 :        441 :         remove_note (insn, note);
    3108                 :            :     }
    3109                 :            : 
    3110                 :            :   /* Cleanup abnormal edges caused by exceptions or non-local gotos.  */
    3111                 :  103362000 :   for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
    3112                 :            :     {
    3113                 :   60461500 :       bool remove = false;
    3114                 :            : 
    3115                 :            :       /* There are three types of edges we need to handle correctly here: EH
    3116                 :            :          edges, abnormal call EH edges, and abnormal call non-EH edges.  The
    3117                 :            :          latter can appear when nonlocal gotos are used.  */
    3118                 :   60461500 :       if (e->flags & EDGE_ABNORMAL_CALL)
    3119                 :            :         {
    3120                 :    2307410 :           if (!CALL_P (insn))
    3121                 :            :             remove = true;
    3122                 :    2307400 :           else if (can_nonlocal_goto (insn))
    3123                 :            :             ;
    3124                 :    2231760 :           else if ((e->flags & EDGE_EH) && can_throw_internal (insn))
    3125                 :            :             ;
    3126                 :          0 :           else if (flag_tm && find_reg_note (insn, REG_TM, NULL))
    3127                 :            :             ;
    3128                 :            :           else
    3129                 :            :             remove = true;
    3130                 :            :         }
    3131                 :   58154100 :       else if (e->flags & EDGE_EH)
    3132                 :    1161700 :         remove = !can_throw_internal (insn);
    3133                 :            : 
    3134                 :    1161700 :       if (remove)
    3135                 :            :         {
    3136                 :     235614 :           remove_edge (e);
    3137                 :     235614 :           df_set_bb_dirty (bb);
    3138                 :     235614 :           purged = true;
    3139                 :            :         }
    3140                 :            :       else
    3141                 :   60225900 :         ei_next (&ei);
    3142                 :            :     }
    3143                 :            : 
    3144                 :   42900500 :   if (JUMP_P (insn))
    3145                 :            :     {
    3146                 :   21680300 :       rtx note;
    3147                 :   21680300 :       edge b,f;
    3148                 :   21680300 :       edge_iterator ei;
    3149                 :            : 
    3150                 :            :       /* We do care only about conditional jumps and simplejumps.  */
    3151                 :   21680300 :       if (!any_condjump_p (insn)
    3152                 :    5806730 :           && !returnjump_p (insn)
    3153                 :   27243000 :           && !simplejump_p (insn))
    3154                 :            :         return purged;
    3155                 :            : 
    3156                 :            :       /* Branch probability/prediction notes are defined only for
    3157                 :            :          condjumps.  We've possibly turned condjump into simplejump.  */
    3158                 :   21644000 :       if (simplejump_p (insn))
    3159                 :            :         {
    3160                 :    5526360 :           note = find_reg_note (insn, REG_BR_PROB, NULL);
    3161                 :    5526360 :           if (note)
    3162                 :       3543 :             remove_note (insn, note);
    3163                 :    5526360 :           while ((note = find_reg_note (insn, REG_BR_PRED, NULL)))
    3164                 :          0 :             remove_note (insn, note);
    3165                 :            :         }
    3166                 :            : 
    3167                 :   59168600 :       for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
    3168                 :            :         {
    3169                 :            :           /* Avoid abnormal flags to leak from computed jumps turned
    3170                 :            :              into simplejumps.  */
    3171                 :            : 
    3172                 :   37524500 :           e->flags &= ~EDGE_ABNORMAL;
    3173                 :            : 
    3174                 :            :           /* See if this edge is one we should keep.  */
    3175                 :   37524500 :           if ((e->flags & EDGE_FALLTHRU) && any_condjump_p (insn))
    3176                 :            :             /* A conditional jump can fall through into the next
    3177                 :            :                block, so we should keep the edge.  */
    3178                 :            :             {
    3179                 :   15873600 :               ei_next (&ei);
    3180                 :   15873600 :               continue;
    3181                 :            :             }
    3182                 :   21650900 :           else if (e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)
    3183                 :   21406800 :                    && BB_HEAD (e->dest) == JUMP_LABEL (insn))
    3184                 :            :             /* If the destination block is the target of the jump,
    3185                 :            :                keep the edge.  */
    3186                 :            :             {
    3187                 :   21399500 :               ei_next (&ei);
    3188                 :   21399500 :               continue;
    3189                 :            :             }
    3190                 :     495479 :           else if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)
    3191                 :     251390 :                    && returnjump_p (insn))
    3192                 :            :             /* If the destination block is the exit block, and this
    3193                 :            :                instruction is a return, then keep the edge.  */
    3194                 :            :             {
    3195                 :     244089 :               ei_next (&ei);
    3196                 :     244089 :               continue;
    3197                 :            :             }
    3198                 :       7301 :           else if ((e->flags & EDGE_EH) && can_throw_internal (insn))
    3199                 :            :             /* Keep the edges that correspond to exceptions thrown by
    3200                 :            :                this instruction and rematerialize the EDGE_ABNORMAL
    3201                 :            :                flag we just cleared above.  */
    3202                 :            :             {
    3203                 :          0 :               e->flags |= EDGE_ABNORMAL;
    3204                 :          0 :               ei_next (&ei);
    3205                 :          0 :               continue;
    3206                 :            :             }
    3207                 :            : 
    3208                 :            :           /* We do not need this edge.  */
    3209                 :       7301 :           df_set_bb_dirty (bb);
    3210                 :       7301 :           purged = true;
    3211                 :       7301 :           remove_edge (e);
    3212                 :            :         }
    3213                 :            : 
    3214                 :   21768100 :       if (EDGE_COUNT (bb->succs) == 0 || !purged)
    3215                 :            :         return purged;
    3216                 :            : 
    3217                 :      87808 :       if (dump_file)
    3218                 :          0 :         fprintf (dump_file, "Purged edges from bb %i\n", bb->index);
    3219                 :            : 
    3220                 :      87808 :       if (!optimize)
    3221                 :            :         return purged;
    3222                 :            : 
    3223                 :            :       /* Redistribute probabilities.  */
    3224                 :      87657 :       if (single_succ_p (bb))
    3225                 :            :         {
    3226                 :      87657 :           single_succ_edge (bb)->probability = profile_probability::always ();
    3227                 :            :         }
    3228                 :            :       else
    3229                 :            :         {
    3230                 :          0 :           note = find_reg_note (insn, REG_BR_PROB, NULL);
    3231                 :          0 :           if (!note)
    3232                 :            :             return purged;
    3233                 :            : 
    3234                 :          0 :           b = BRANCH_EDGE (bb);
    3235                 :          0 :           f = FALLTHRU_EDGE (bb);
    3236                 :          0 :           b->probability = profile_probability::from_reg_br_prob_note
    3237                 :          0 :                                          (XINT (note, 0));
    3238                 :          0 :           f->probability = b->probability.invert ();
    3239                 :            :         }
    3240                 :            : 
    3241                 :      87657 :       return purged;
    3242                 :            :     }
    3243                 :   21220100 :   else if (CALL_P (insn) && SIBLING_CALL_P (insn))
    3244                 :            :     {
    3245                 :            :       /* First, there should not be any EH or ABCALL edges resulting
    3246                 :            :          from non-local gotos and the like.  If there were, we shouldn't
    3247                 :            :          have created the sibcall in the first place.  Second, there
    3248                 :            :          should of course never have been a fallthru edge.  */
    3249                 :     340814 :       gcc_assert (single_succ_p (bb));
    3250                 :     340814 :       gcc_assert (single_succ_edge (bb)->flags
    3251                 :            :                   == (EDGE_SIBCALL | EDGE_ABNORMAL));
    3252                 :            : 
    3253                 :            :       return 0;
    3254                 :            :     }
    3255                 :            : 
    3256                 :            :   /* If we don't see a jump insn, we don't know exactly why the block would
    3257                 :            :      have been broken at this point.  Look for a simple, non-fallthru edge,
    3258                 :            :      as these are only created by conditional branches.  If we find such an
    3259                 :            :      edge we know that there used to be a jump here and can then safely
    3260                 :            :      remove all non-fallthru edges.  */
    3261                 :   20879300 :   found = false;
    3262                 :   42811700 :   FOR_EACH_EDGE (e, ei, bb->succs)
    3263                 :   22080100 :     if (! (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU)))
    3264                 :            :       {
    3265                 :            :         found = true;
    3266                 :            :         break;
    3267                 :            :       }
    3268                 :            : 
    3269                 :   20879300 :   if (!found)
    3270                 :            :     return purged;
    3271                 :            : 
    3272                 :            :   /* Remove all but the fake and fallthru edges.  The fake edge may be
    3273                 :            :      the only successor for this block in the case of noreturn
    3274                 :            :      calls.  */
    3275                 :     443109 :   for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
    3276                 :            :     {
    3277                 :     295416 :       if (!(e->flags & (EDGE_FALLTHRU | EDGE_FAKE)))
    3278                 :            :         {
    3279                 :     147723 :           df_set_bb_dirty (bb);
    3280                 :     147723 :           remove_edge (e);
    3281                 :     147723 :           purged = true;
    3282                 :            :         }
    3283                 :            :       else
    3284                 :     147693 :         ei_next (&ei);
    3285                 :            :     }
    3286                 :            : 
    3287                 :     147693 :   gcc_assert (single_succ_p (bb));
    3288                 :            : 
    3289                 :     147693 :   single_succ_edge (bb)->probability = profile_probability::always ();
    3290                 :            : 
    3291                 :     147693 :   if (dump_file)
    3292                 :          1 :     fprintf (dump_file, "Purged non-fallthru edges from bb %i\n",
    3293                 :            :              bb->index);
    3294                 :            :   return purged;
    3295                 :            : }
    3296                 :            : 
    3297                 :            : /* Search all basic blocks for potentially dead edges and purge them.  Return
    3298                 :            :    true if some edge has been eliminated.  */
    3299                 :            : 
    3300                 :            : bool
    3301                 :    2021550 : purge_all_dead_edges (void)
    3302                 :            : {
    3303                 :    2021550 :   int purged = false;
    3304                 :    2021550 :   basic_block bb;
    3305                 :            : 
    3306                 :   28584800 :   FOR_EACH_BB_FN (bb, cfun)
    3307                 :            :     {
    3308                 :   26563200 :       bool purged_here = purge_dead_edges (bb);
    3309                 :            : 
    3310                 :   26563200 :       purged |= purged_here;
    3311                 :            :     }
    3312                 :            : 
    3313                 :    2021550 :   return purged;
    3314                 :            : }
    3315                 :            : 
    3316                 :            : /* This is used by a few passes that emit some instructions after abnormal
    3317                 :            :    calls, moving the basic block's end, while they in fact do want to emit
    3318                 :            :    them on the fallthru edge.  Look for abnormal call edges, find backward
    3319                 :            :    the call in the block and insert the instructions on the edge instead.
    3320                 :            : 
    3321                 :            :    Similarly, handle instructions throwing exceptions internally.
    3322                 :            : 
    3323                 :            :    Return true when instructions have been found and inserted on edges.  */
    3324                 :            : 
    3325                 :            : bool
    3326                 :     967242 : fixup_abnormal_edges (void)
    3327                 :            : {
    3328                 :     967242 :   bool inserted = false;
    3329                 :     967242 :   basic_block bb;
    3330                 :            : 
    3331                 :   10820300 :   FOR_EACH_BB_FN (bb, cfun)
    3332                 :            :     {
    3333                 :    9853050 :       edge e;
    3334                 :    9853050 :       edge_iterator ei;
    3335                 :            : 
    3336                 :            :       /* Look for cases we are interested in - calls or instructions causing
    3337                 :            :          exceptions.  */
    3338                 :   23076000 :       FOR_EACH_EDGE (e, ei, bb->succs)
    3339                 :   13711600 :         if ((e->flags & EDGE_ABNORMAL_CALL)
    3340                 :   13303200 :             || ((e->flags & (EDGE_ABNORMAL | EDGE_EH))
    3341                 :            :                 == (EDGE_ABNORMAL | EDGE_EH)))
    3342                 :            :           break;
    3343                 :            : 
    3344                 :    9853050 :       if (e && !CALL_P (BB_END (bb)) && !can_throw_internal (BB_END (bb)))
    3345                 :            :         {
    3346                 :       6119 :           rtx_insn *insn;
    3347                 :            : 
    3348                 :            :           /* Get past the new insns generated.  Allow notes, as the insns
    3349                 :            :              may be already deleted.  */
    3350                 :       6119 :           insn = BB_END (bb);
    3351                 :      17658 :           while ((NONJUMP_INSN_P (insn) || NOTE_P (insn))
    3352                 :      17500 :                  && !can_throw_internal (insn)
    3353                 :      29673 :                  && insn != BB_HEAD (bb))
    3354                 :      11539 :             insn = PREV_INSN (insn);
    3355                 :            : 
    3356                 :       6119 :           if (CALL_P (insn) || can_throw_internal (insn))
    3357                 :            :             {
    3358                 :       5496 :               rtx_insn *stop, *next;
    3359                 :            : 
    3360                 :       5496 :               e = find_fallthru_edge (bb->succs);
    3361                 :            : 
    3362                 :       5496 :               stop = NEXT_INSN (BB_END (bb));
    3363                 :       5496 :               BB_END (bb) = insn;
    3364                 :            : 
    3365                 :       5496 :               for (insn = NEXT_INSN (insn); insn != stop; insn = next)
    3366                 :            :                 {
    3367                 :       9661 :                   next = NEXT_INSN (insn);
    3368                 :       9661 :                   if (INSN_P (insn))
    3369                 :            :                     {
    3370                 :       5268 :                       delete_insn (insn);
    3371                 :            : 
    3372                 :            :                       /* Sometimes there's still the return value USE.
    3373                 :            :                          If it's placed after a trapping call (i.e. that
    3374                 :            :                          call is the last insn anyway), we have no fallthru
    3375                 :            :                          edge.  Simply delete this use and don't try to insert
    3376                 :            :                          on the non-existent edge.
    3377                 :            :                          Similarly, sometimes a call that can throw is
    3378                 :            :                          followed in the source with __builtin_unreachable (),
    3379                 :            :                          meaning that there is UB if the call returns rather
    3380                 :            :                          than throws.  If there weren't any instructions
    3381                 :            :                          following such calls before, supposedly even the ones
    3382                 :            :                          we've deleted aren't significant and can be
    3383                 :            :                          removed.  */
    3384                 :       5268 :                       if (e)
    3385                 :            :                         {
    3386                 :            :                           /* We're not deleting it, we're moving it.  */
    3387                 :       5267 :                           insn->set_undeleted ();
    3388                 :       5267 :                           SET_PREV_INSN (insn) = NULL_RTX;
    3389                 :       5267 :                           SET_NEXT_INSN (insn) = NULL_RTX;
    3390                 :            : 
    3391                 :       5267 :                           insert_insn_on_edge (insn, e);
    3392                 :       5267 :                           inserted = true;
    3393                 :            :                         }
    3394                 :            :                     }
    3395                 :       4393 :                   else if (!BARRIER_P (insn))
    3396                 :      19550 :                     set_block_for_insn (insn, NULL);
    3397                 :            :                 }
    3398                 :            :             }
    3399                 :            : 
    3400                 :            :           /* It may be that we don't find any trapping insn.  In this
    3401                 :            :              case we discovered quite late that the insn that had been
    3402                 :            :              marked as can_throw_internal in fact couldn't trap at all.
    3403                 :            :              So we should in fact delete the EH edges out of the block.  */
    3404                 :            :           else
    3405                 :        623 :             purge_dead_edges (bb);
    3406                 :            :         }
    3407                 :            :     }
    3408                 :            : 
    3409                 :     967242 :   return inserted;
    3410                 :            : }
    3411                 :            : 
    3412                 :            : /* Cut the insns from FIRST to LAST out of the insns stream.  */
    3413                 :            : 
    3414                 :            : rtx_insn *
    3415                 :    7576930 : unlink_insn_chain (rtx_insn *first, rtx_insn *last)
    3416                 :            : {
    3417                 :    7576930 :   rtx_insn *prevfirst = PREV_INSN (first);
    3418                 :    7576930 :   rtx_insn *nextlast = NEXT_INSN (last);
    3419                 :            : 
    3420                 :    7576930 :   SET_PREV_INSN (first) = NULL;
    3421                 :    7576930 :   SET_NEXT_INSN (last) = NULL;
    3422                 :    7576930 :   if (prevfirst)
    3423                 :    5946330 :     SET_NEXT_INSN (prevfirst) = nextlast;
    3424                 :    7576930 :   if (nextlast)
    3425                 :    6628220 :     SET_PREV_INSN (nextlast) = prevfirst;
    3426                 :            :   else
    3427                 :     948706 :     set_last_insn (prevfirst);
    3428                 :    7576930 :   if (!prevfirst)
    3429                 :    1630600 :     set_first_insn (nextlast);
    3430                 :    7576930 :   return first;
    3431                 :            : }
    3432                 :            : 
    3433                 :            : /* Skip over inter-block insns occurring after BB which are typically
    3434                 :            :    associated with BB (e.g., barriers). If there are any such insns,
    3435                 :            :    we return the last one. Otherwise, we return the end of BB.  */
    3436                 :            : 
    3437                 :            : static rtx_insn *
    3438                 :   16724100 : skip_insns_after_block (basic_block bb)
    3439                 :            : {
    3440                 :   16724100 :   rtx_insn *insn, *last_insn, *next_head, *prev;
    3441                 :            : 
    3442                 :   16724100 :   next_head = NULL;
    3443                 :   16724100 :   if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun))
    3444                 :   15093400 :     next_head = BB_HEAD (bb->next_bb);
    3445                 :            : 
    3446                 :   22331400 :   for (last_insn = insn = BB_END (bb); (insn = NEXT_INSN (insn)) != 0; )
    3447                 :            :     {
    3448                 :   20700800 :       if (insn == next_head)
    3449                 :            :         break;
    3450                 :            : 
    3451                 :    5607340 :       switch (GET_CODE (insn))
    3452                 :            :         {
    3453                 :    4899150 :         case BARRIER:
    3454                 :    4899150 :           last_insn = insn;
    3455                 :    4899150 :           continue;
    3456                 :            : 
    3457                 :     695169 :         case NOTE:
    3458                 :     695169 :           switch (NOTE_KIND (insn))
    3459                 :            :             {
    3460                 :          0 :             case NOTE_INSN_BLOCK_END:
    3461                 :          0 :               gcc_unreachable ();
    3462                 :            :               continue;
    3463                 :     695169 :             default:
    3464                 :     695169 :               continue;
    3465                 :            :               break;
    3466                 :            :             }
    3467                 :            :           break;
    3468                 :            : 
    3469                 :      13016 :         case CODE_LABEL:
    3470                 :      13016 :           if (NEXT_INSN (insn)
    3471                 :      13016 :               && JUMP_TABLE_DATA_P (NEXT_INSN (insn)))
    3472                 :            :             {
    3473                 :      13016 :               insn = NEXT_INSN (insn);
    3474                 :      13016 :               last_insn = insn;
    3475                 :      13016 :               continue;
    3476                 :            :             }
    3477                 :            :           break;
    3478                 :            : 
    3479                 :            :         default:
    3480                 :            :           break;
    3481                 :            :         }
    3482                 :            : 
    3483                 :            :       break;
    3484                 :            :     }
    3485                 :            : 
    3486                 :            :   /* It is possible to hit contradictory sequence.  For instance:
    3487                 :            : 
    3488                 :            :      jump_insn
    3489                 :            :      NOTE_INSN_BLOCK_BEG
    3490                 :            :      barrier
    3491                 :            : 
    3492                 :            :      Where barrier belongs to jump_insn, but the note does not.  This can be
    3493                 :            :      created by removing the basic block originally following
    3494                 :            :      NOTE_INSN_BLOCK_BEG.  In such case reorder the notes.  */
    3495                 :            : 
    3496                 :   21649300 :   for (insn = last_insn; insn != BB_END (bb); insn = prev)
    3497                 :            :     {
    3498                 :    4925270 :       prev = PREV_INSN (insn);
    3499                 :    4925270 :       if (NOTE_P (insn))
    3500                 :         84 :         switch (NOTE_KIND (insn))
    3501                 :            :           {
    3502                 :          0 :           case NOTE_INSN_BLOCK_END:
    3503                 :          0 :             gcc_unreachable ();
    3504                 :         84 :             break;
    3505                 :         84 :           case NOTE_INSN_DELETED:
    3506                 :         84 :           case NOTE_INSN_DELETED_LABEL:
    3507                 :         84 :           case NOTE_INSN_DELETED_DEBUG_LABEL:
    3508                 :         84 :             continue;
    3509                 :          0 :           default:
    3510                 :          0 :             reorder_insns (insn, insn, last_insn);
    3511                 :            :           }
    3512                 :            :     }
    3513                 :            : 
    3514                 :   16724100 :   return last_insn;
    3515                 :            : }
    3516                 :            : 
    3517                 :            : /* Locate or create a label for a given basic block.  */
    3518                 :            : 
    3519                 :            : static rtx_insn *
    3520                 :    1458490 : label_for_bb (basic_block bb)
    3521                 :            : {
    3522                 :    1458490 :   rtx_insn *label = BB_HEAD (bb);
    3523                 :            : 
    3524                 :    1458490 :   if (!LABEL_P (label))
    3525                 :            :     {
    3526                 :     896721 :       if (dump_file)
    3527                 :          4 :         fprintf (dump_file, "Emitting label for block %d\n", bb->index);
    3528                 :            : 
    3529                 :     896721 :       label = block_label (bb);
    3530                 :            :     }
    3531                 :            : 
    3532                 :    1458490 :   return label;
    3533                 :            : }
    3534                 :            : 
    3535                 :            : /* Locate the effective beginning and end of the insn chain for each
    3536                 :            :    block, as defined by skip_insns_after_block above.  */
    3537                 :            : 
    3538                 :            : static void
    3539                 :    1630610 : record_effective_endpoints (void)
    3540                 :            : {
    3541                 :    1630610 :   rtx_insn *next_insn;
    3542                 :    1630610 :   basic_block bb;
    3543                 :    1630610 :   rtx_insn *insn;
    3544                 :            : 
    3545                 :    1630610 :   for (insn = get_insns ();
    3546                 :            :        insn
    3547                 :    3263070 :        && NOTE_P (insn)
    3548                 :    6525410 :        && NOTE_KIND (insn) != NOTE_INSN_BASIC_BLOCK;
    3549                 :    1632470 :        insn = NEXT_INSN (insn))
    3550                 :    1632470 :     continue;
    3551                 :            :   /* No basic blocks at all?  */
    3552                 :    1630610 :   gcc_assert (insn);
    3553                 :            : 
    3554                 :    1630610 :   if (PREV_INSN (insn))
    3555                 :    1630600 :     cfg_layout_function_header =
    3556                 :    1630600 :             unlink_insn_chain (get_insns (), PREV_INSN (insn));
    3557                 :            :   else
    3558                 :          1 :     cfg_layout_function_header = NULL;
    3559                 :            : 
    3560                 :    1630610 :   next_insn = get_insns ();
    3561                 :   18354700 :   FOR_EACH_BB_FN (bb, cfun)
    3562                 :            :     {
    3563                 :   16724100 :       rtx_insn *end;
    3564                 :            : 
    3565                 :   16724100 :       if (PREV_INSN (BB_HEAD (bb)) && next_insn != BB_HEAD (bb))
    3566                 :      19725 :         BB_HEADER (bb) = unlink_insn_chain (next_insn,
    3567                 :            :                                                 PREV_INSN (BB_HEAD (bb)));
    3568                 :   16724100 :       end = skip_insns_after_block (bb);
    3569                 :   16724100 :       if (NEXT_INSN (BB_END (bb)) && BB_END (bb) != end)
    3570                 :    4878830 :         BB_FOOTER (bb) = unlink_insn_chain (NEXT_INSN (BB_END (bb)), end);
    3571                 :   16724100 :       next_insn = NEXT_INSN (BB_END (bb));
    3572                 :            :     }
    3573                 :            : 
    3574                 :    1630610 :   cfg_layout_function_footer = next_insn;
    3575                 :    1630610 :   if (cfg_layout_function_footer)
    3576                 :     673488 :     cfg_layout_function_footer = unlink_insn_chain (cfg_layout_function_footer, get_last_insn ());
    3577                 :    1630610 : }
    3578                 :            : 
    3579                 :            : namespace {
    3580                 :            : 
    3581                 :            : const pass_data pass_data_into_cfg_layout_mode =
    3582                 :            : {
    3583                 :            :   RTL_PASS, /* type */
    3584                 :            :   "into_cfglayout", /* name */
    3585                 :            :   OPTGROUP_NONE, /* optinfo_flags */
    3586                 :            :   TV_CFG, /* tv_id */
    3587                 :            :   0, /* properties_required */
    3588                 :            :   PROP_cfglayout, /* properties_provided */
    3589                 :            :   0, /* properties_destroyed */
    3590                 :            :   0, /* todo_flags_start */
    3591                 :            :   0, /* todo_flags_finish */
    3592                 :            : };
    3593                 :            : 
    3594                 :            : class pass_into_cfg_layout_mode : public rtl_opt_pass
    3595                 :            : {
    3596                 :            : public:
    3597                 :     200540 :   pass_into_cfg_layout_mode (gcc::context *ctxt)
    3598                 :     401080 :     : rtl_opt_pass (pass_data_into_cfg_layout_mode, ctxt)
    3599                 :            :   {}
    3600                 :            : 
    3601                 :            :   /* opt_pass methods: */
    3602                 :     942956 :   virtual unsigned int execute (function *)
    3603                 :            :     {
    3604                 :     942956 :       cfg_layout_initialize (0);
    3605                 :     942956 :       return 0;
    3606                 :            :     }
    3607                 :            : 
    3608                 :            : }; // class pass_into_cfg_layout_mode
    3609                 :            : 
    3610                 :            : } // anon namespace
    3611                 :            : 
    3612                 :            : rtl_opt_pass *
    3613                 :     200540 : make_pass_into_cfg_layout_mode (gcc::context *ctxt)
    3614                 :            : {
    3615                 :     200540 :   return new pass_into_cfg_layout_mode (ctxt);
    3616                 :            : }
    3617                 :            : 
    3618                 :            : namespace {
    3619                 :            : 
    3620                 :            : const pass_data pass_data_outof_cfg_layout_mode =
    3621                 :            : {
    3622                 :            :   RTL_PASS, /* type */
    3623                 :            :   "outof_cfglayout", /* name */
    3624                 :            :   OPTGROUP_NONE, /* optinfo_flags */
    3625                 :            :   TV_CFG, /* tv_id */
    3626                 :            :   0, /* properties_required */
    3627                 :            :   0, /* properties_provided */
    3628                 :            :   PROP_cfglayout, /* properties_destroyed */
    3629                 :            :   0, /* todo_flags_start */
    3630                 :            :   0, /* todo_flags_finish */
    3631                 :            : };
    3632                 :            : 
    3633                 :            : class pass_outof_cfg_layout_mode : public rtl_opt_pass
    3634                 :            : {
    3635                 :            : public:
    3636                 :     200540 :   pass_outof_cfg_layout_mode (gcc::context *ctxt)
    3637                 :     401080 :     : rtl_opt_pass (pass_data_outof_cfg_layout_mode, ctxt)
    3638                 :            :   {}
    3639                 :            : 
    3640                 :            :   /* opt_pass methods: */
    3641                 :            :   virtual unsigned int execute (function *);
    3642                 :            : 
    3643                 :            : }; // class pass_outof_cfg_layout_mode
    3644                 :            : 
    3645                 :            : unsigned int
    3646                 :     942957 : pass_outof_cfg_layout_mode::execute (function *fun)
    3647                 :            : {
    3648                 :     942957 :   basic_block bb;
    3649                 :            : 
    3650                 :    9444600 :   FOR_EACH_BB_FN (bb, fun)
    3651                 :    8501650 :     if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (fun))
    3652                 :    7558690 :       bb->aux = bb->next_bb;
    3653                 :            : 
    3654                 :     942957 :   cfg_layout_finalize ();
    3655                 :            : 
    3656                 :     942957 :   return 0;
    3657                 :            : }
    3658                 :            : 
    3659                 :            : } // anon namespace
    3660                 :            : 
    3661                 :            : rtl_opt_pass *
    3662                 :     200540 : make_pass_outof_cfg_layout_mode (gcc::context *ctxt)
    3663                 :            : {
    3664                 :     200540 :   return new pass_outof_cfg_layout_mode (ctxt);
    3665                 :            : }
    3666                 :            : 
    3667                 :            : 
    3668                 :            : /* Link the basic blocks in the correct order, compacting the basic
    3669                 :            :    block queue while at it.  If STAY_IN_CFGLAYOUT_MODE is false, this
    3670                 :            :    function also clears the basic block header and footer fields.
    3671                 :            : 
    3672                 :            :    This function is usually called after a pass (e.g. tracer) finishes
    3673                 :            :    some transformations while in cfglayout mode.  The required sequence
    3674                 :            :    of the basic blocks is in a linked list along the bb->aux field.
    3675                 :            :    This functions re-links the basic block prev_bb and next_bb pointers
    3676                 :            :    accordingly, and it compacts and renumbers the blocks.
    3677                 :            : 
    3678                 :            :    FIXME: This currently works only for RTL, but the only RTL-specific
    3679                 :            :    bits are the STAY_IN_CFGLAYOUT_MODE bits.  The tracer pass was moved
    3680                 :            :    to GIMPLE a long time ago, but it doesn't relink the basic block
    3681                 :            :    chain.  It could do that (to give better initial RTL) if this function
    3682                 :            :    is made IR-agnostic (and moved to cfganal.c or cfg.c while at it).  */
    3683                 :            : 
    3684                 :            : void
    3685                 :    2066900 : relink_block_chain (bool stay_in_cfglayout_mode)
    3686                 :            : {
    3687                 :    2066900 :   basic_block bb, prev_bb;
    3688                 :    2066900 :   int index;
    3689                 :            : 
    3690                 :            :   /* Maybe dump the re-ordered sequence.  */
    3691                 :    2066900 :   if (dump_file)
    3692                 :            :     {
    3693                 :        175 :       fprintf (dump_file, "Reordered sequence:\n");
    3694                 :        175 :       for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb, index =
    3695                 :            :            NUM_FIXED_BLOCKS;
    3696                 :       1095 :            bb;
    3697                 :        920 :            bb = (basic_block) bb->aux, index++)
    3698                 :            :         {
    3699                 :        920 :           fprintf (dump_file, " %i ", index);
    3700                 :        920 :           if (get_bb_original (bb))
    3701                 :         30 :             fprintf (dump_file, "duplicate of %i\n",
    3702                 :         30 :                      get_bb_original (bb)->index);
    3703                 :        890 :           else if (forwarder_block_p (bb)
    3704                 :        890 :                    && !LABEL_P (BB_HEAD (bb)))
    3705                 :         21 :             fprintf (dump_file, "compensation\n");
    3706                 :            :           else
    3707                 :        869 :             fprintf (dump_file, "bb %i\n", bb->index);
    3708                 :            :         }
    3709                 :            :     }
    3710                 :            : 
    3711                 :            :   /* Now reorder the blocks.  */
    3712                 :    2066900 :   prev_bb = ENTRY_BLOCK_PTR_FOR_FN (cfun);
    3713                 :    2066900 :   bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb;
    3714                 :   24493200 :   for (; bb; prev_bb = bb, bb = (basic_block) bb->aux)
    3715                 :            :     {
    3716                 :   22426300 :       bb->prev_bb = prev_bb;
    3717                 :   22426300 :       prev_bb->next_bb = bb;
    3718                 :            :     }
    3719                 :    2066900 :   prev_bb->next_bb = EXIT_BLOCK_PTR_FOR_FN (cfun);
    3720                 :    2066900 :   EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb = prev_bb;
    3721                 :            : 
    3722                 :            :   /* Then, clean up the aux fields.  */
    3723                 :   28627000 :   FOR_ALL_BB_FN (bb, cfun)
    3724                 :            :     {
    3725                 :   26560100 :       bb->aux = NULL;
    3726                 :   26560100 :       if (!stay_in_cfglayout_mode)
    3727                 :   19000700 :         BB_HEADER (bb) = BB_FOOTER (bb) = NULL;
    3728                 :            :     }
    3729                 :            : 
    3730                 :            :   /* Maybe reset the original copy tables, they are not valid anymore
    3731                 :            :      when we renumber the basic blocks in compact_blocks.  If we are
    3732                 :            :      are going out of cfglayout mode, don't re-allocate the tables.  */
    3733                 :    2066900 :   if (original_copy_tables_initialized_p ())
    3734                 :    2066900 :     free_original_copy_tables ();
    3735                 :    2066900 :   if (stay_in_cfglayout_mode)
    3736                 :     436296 :     initialize_original_copy_tables ();
    3737                 :            : 
    3738                 :            :   /* Finally, put basic_block_info in the new order.  */
    3739                 :    2066900 :   compact_blocks ();
    3740                 :    2066900 : }
    3741                 :            : 
    3742                 :            : 
    3743                 :            : /* Given a reorder chain, rearrange the code to match.  */
    3744                 :            : 
    3745                 :            : static void
    3746                 :    1630610 : fixup_reorder_chain (void)
    3747                 :            : {
    3748                 :    1630610 :   basic_block bb;
    3749                 :    1630610 :   rtx_insn *insn = NULL;
    3750                 :            : 
    3751                 :    1630610 :   if (cfg_layout_function_header)
    3752                 :            :     {
    3753                 :    1630600 :       set_first_insn (cfg_layout_function_header);
    3754                 :    1630600 :       insn = cfg_layout_function_header;
    3755                 :    1632470 :       while (NEXT_INSN (insn))
    3756                 :    1632470 :         insn = NEXT_INSN (insn);
    3757                 :            :     }
    3758                 :            : 
    3759                 :            :   /* First do the bulk reordering -- rechain the blocks without regard to
    3760                 :            :      the needed changes to jumps and labels.  */
    3761                 :            : 
    3762                 :   16893900 :   for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb; bb = (basic_block)
    3763                 :            :        bb->aux)
    3764                 :            :     {
    3765                 :   15263300 :       if (BB_HEADER (bb))
    3766                 :            :         {
    3767                 :      19626 :           if (insn)
    3768                 :      19626 :             SET_NEXT_INSN (insn) = BB_HEADER (bb);
    3769                 :            :           else
    3770                 :          0 :             set_first_insn (BB_HEADER (bb));
    3771                 :      19626 :           SET_PREV_INSN (BB_HEADER (bb)) = insn;
    3772                 :      19626 :           insn = BB_HEADER (bb);
    3773                 :      21214 :           while (NEXT_INSN (insn))
    3774                 :      21214 :             insn = NEXT_INSN (insn);
    3775                 :            :         }
    3776                 :   15263300 :       if (insn)
    3777                 :   15263300 :         SET_NEXT_INSN (insn) = BB_HEAD (bb);
    3778                 :            :       else
    3779                 :          2 :         set_first_insn (BB_HEAD (bb));
    3780                 :   15263300 :       SET_PREV_INSN (BB_HEAD (bb)) = insn;
    3781                 :   15263300 :       insn = BB_END (bb);
    3782                 :   15263300 :       if (BB_FOOTER (bb))
    3783                 :            :         {
    3784                 :    1967070 :           SET_NEXT_INSN (insn) = BB_FOOTER (bb);
    3785                 :    1967070 :           SET_PREV_INSN (BB_FOOTER (bb)) = insn;
    3786                 :    3972640 :           while (NEXT_INSN (insn))
    3787                 :    3972640 :             insn = NEXT_INSN (insn);
    3788                 :            :         }
    3789                 :            :     }
    3790                 :            : 
    3791                 :    1630610 :   SET_NEXT_INSN (insn) = cfg_layout_function_footer;
    3792                 :    1630610 :   if (cfg_layout_function_footer)
    3793                 :     673506 :     SET_PREV_INSN (cfg_layout_function_footer) = insn;
    3794                 :            : 
    3795                 :    2304490 :   while (NEXT_INSN (insn))
    3796                 :    2304490 :     insn = NEXT_INSN (insn);
    3797                 :            : 
    3798                 :    1630610 :   set_last_insn (insn);
    3799                 :    1630610 :   if (flag_checking)
    3800                 :    1630580 :     verify_insn_chain ();
    3801                 :            : 
    3802                 :            :   /* Now add jumps and labels as needed to match the blocks new
    3803                 :            :      outgoing edges.  */
    3804                 :            : 
    3805                 :   16893900 :   for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb ; bb = (basic_block)
    3806                 :            :        bb->aux)
    3807                 :            :     {
    3808                 :   15263300 :       edge e_fall, e_taken, e;
    3809                 :   15263300 :       rtx_insn *bb_end_insn;
    3810                 :   15263300 :       rtx ret_label = NULL_RTX;
    3811                 :   15263300 :       basic_block nb;
    3812                 :   15263300 :       edge_iterator ei;
    3813                 :            : 
    3814                 :   15263300 :       if (EDGE_COUNT (bb->succs) == 0)
    3815                 :   12727800 :         continue;
    3816                 :            : 
    3817                 :            :       /* Find the old fallthru edge, and another non-EH edge for
    3818                 :            :          a taken jump.  */
    3819                 :   14396700 :       e_taken = e_fall = NULL;
    3820                 :            : 
    3821                 :   36789900 :       FOR_EACH_EDGE (e, ei, bb->succs)
    3822                 :   22393200 :         if (e->flags & EDGE_FALLTHRU)
    3823                 :            :           e_fall = e;
    3824                 :    9096730 :         else if (! (e->flags & EDGE_EH))
    3825                 :    8175370 :           e_taken = e;
    3826                 :            : 
    3827                 :   14396700 :       bb_end_insn = BB_END (bb);
    3828                 :   14396700 :       if (rtx_jump_insn *bb_end_jump = dyn_cast <rtx_jump_insn *> (bb_end_insn))
    3829                 :            :         {
    3830                 :    7864800 :           ret_label = JUMP_LABEL (bb_end_jump);
    3831                 :    7864800 :           if (any_condjump_p (bb_end_jump))
    3832                 :            :             {
    3833                 :            :               /* This might happen if the conditional jump has side
    3834                 :            :                  effects and could therefore not be optimized away.
    3835                 :            :                  Make the basic block to end with a barrier in order
    3836                 :            :                  to prevent rtl_verify_flow_info from complaining.  */
    3837                 :    7012020 :               if (!e_fall)
    3838                 :            :                 {
    3839                 :          0 :                   gcc_assert (!onlyjump_p (bb_end_jump)
    3840                 :            :                               || returnjump_p (bb_end_jump)
    3841                 :            :                               || (e_taken->flags & EDGE_CROSSING));
    3842                 :          0 :                   emit_barrier_after (bb_end_jump);
    3843                 :          0 :                   continue;
    3844                 :            :                 }
    3845                 :            : 
    3846                 :            :               /* If the old fallthru is still next, nothing to do.  */
    3847                 :    7012020 :               if (bb->aux == e_fall->dest
    3848                 :    1736770 :                   || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
    3849                 :    5275250 :                 continue;
    3850                 :            : 
    3851                 :            :               /* The degenerated case of conditional jump jumping to the next
    3852                 :            :                  instruction can happen for jumps with side effects.  We need
    3853                 :            :                  to construct a forwarder block and this will be done just
    3854                 :            :                  fine by force_nonfallthru below.  */
    3855                 :    1736760 :               if (!e_taken)
    3856                 :            :                 ;
    3857                 :            : 
    3858                 :            :               /* There is another special case: if *neither* block is next,
    3859                 :            :                  such as happens at the very end of a function, then we'll
    3860                 :            :                  need to add a new unconditional jump.  Choose the taken
    3861                 :            :                  edge based on known or assumed probability.  */
    3862                 :    1736760 :               else if (bb->aux != e_taken->dest)
    3863                 :            :                 {
    3864                 :     369307 :                   rtx note = find_reg_note (bb_end_jump, REG_BR_PROB, 0);
    3865                 :            : 
    3866                 :     369307 :                   if (note
    3867                 :            :                       && profile_probability::from_reg_br_prob_note
    3868                 :     587896 :                                  (XINT (note, 0)) < profile_probability::even ()
    3869                 :     503764 :                       && invert_jump (bb_end_jump,
    3870                 :     134457 :                                       (e_fall->dest
    3871                 :     134457 :                                        == EXIT_BLOCK_PTR_FOR_FN (cfun)
    3872                 :            :                                        ? NULL_RTX
    3873                 :     134457 :                                        : label_for_bb (e_fall->dest)), 0))
    3874                 :            :                     {
    3875                 :     134457 :                       e_fall->flags &= ~EDGE_FALLTHRU;
    3876                 :     134457 :                       gcc_checking_assert (could_fall_through
    3877                 :            :                                            (e_taken->src, e_taken->dest));
    3878                 :     134457 :                       e_taken->flags |= EDGE_FALLTHRU;
    3879                 :     134457 :                       update_br_prob_note (bb);
    3880                 :     134457 :                       e = e_fall, e_fall = e_taken, e_taken = e;
    3881                 :            :                     }
    3882                 :            :                 }
    3883                 :            : 
    3884                 :            :               /* If the "jumping" edge is a crossing edge, and the fall
    3885                 :            :                  through edge is non-crossing, leave things as they are.  */
    3886                 :    1367460 :               else if ((e_taken->flags & EDGE_CROSSING)
    3887                 :      43426 :                        && !(e_fall->flags & EDGE_CROSSING))
    3888                 :      43426 :                 continue;
    3889                 :            : 
    3890                 :            :               /* Otherwise we can try to invert the jump.  This will
    3891                 :            :                  basically never fail, however, keep up the pretense.  */
    3892                 :    1324030 :               else if (invert_jump (bb_end_jump,
    3893                 :            :                                     (e_fall->dest
    3894                 :            :                                      == EXIT_BLOCK_PTR_FOR_FN (cfun)
    3895                 :            :                                      ? NULL_RTX
    3896                 :    1324030 :                                      : label_for_bb (e_fall->dest)), 0))
    3897                 :            :                 {
    3898                 :    1324030 :                   e_fall->flags &= ~EDGE_FALLTHRU;
    3899                 :    1324030 :                   gcc_checking_assert (could_fall_through
    3900                 :            :                                        (e_taken->src, e_taken->dest));
    3901                 :    1324030 :                   e_taken->flags |= EDGE_FALLTHRU;
    3902                 :    1324030 :                   update_br_prob_note (bb);
    3903                 :    1324030 :                   if (LABEL_NUSES (ret_label) == 0
    3904                 :    1324030 :                       && single_pred_p (e_taken->dest))
    3905                 :     771021 :                     delete_insn (as_a<rtx_insn *> (ret_label));
    3906                 :    1324030 :                   continue;
    3907                 :            :                 }
    3908                 :            :             }
    3909                 :     852788 :           else if (extract_asm_operands (PATTERN (bb_end_insn)) != NULL)
    3910                 :            :             {
    3911                 :            :               /* If the old fallthru is still next or if
    3912                 :            :                  asm goto doesn't have a fallthru (e.g. when followed by
    3913                 :            :                  __builtin_unreachable ()), nothing to do.  */
    3914                 :        461 :               if (! e_fall
    3915                 :        409 :                   || bb->aux == e_fall->dest
    3916                 :         40 :                   || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
    3917                 :        421 :                 continue;
    3918                 :            : 
    3919                 :            :               /* Otherwise we'll have to use the fallthru fixup below.  */
    3920                 :            :             }
    3921                 :            :           else
    3922                 :            :             {
    3923                 :            :               /* Otherwise we have some return, switch or computed
    3924                 :            :                  jump.  In the 99% case, there should not have been a
    3925                 :            :                  fallthru edge.  */
    3926                 :     852327 :               gcc_assert (returnjump_p (bb_end_insn) || !e_fall);
    3927                 :     852327 :               continue;
    3928                 :            :             }
    3929                 :            :         }
    3930                 :            :       else
    3931                 :            :         {
    3932                 :            :           /* No fallthru implies a noreturn function with EH edges, or
    3933                 :            :              something similarly bizarre.  In any case, we don't need to
    3934                 :            :              do anything.  */
    3935                 :    6531930 :           if (! e_fall)
    3936                 :     247891 :             continue;
    3937                 :            : 
    3938                 :            :           /* If the fallthru block is still next, nothing to do.  */
    3939                 :    6284040 :           if (bb->aux == e_fall->dest)
    3940                 :    3247540 :             continue;
    3941                 :            : 
    3942                 :            :           /* A fallthru to exit block.  */
    3943                 :    3036500 :           if (e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
    3944                 :     870382 :             continue;
    3945                 :            :         }
    3946                 :            : 
    3947                 :            :       /* We got here if we need to add a new jump insn. 
    3948                 :            :          Note force_nonfallthru can delete E_FALL and thus we have to
    3949                 :            :          save E_FALL->src prior to the call to force_nonfallthru.  */
    3950                 :    2535460 :       nb = force_nonfallthru_and_redirect (e_fall, e_fall->dest, ret_label);
    3951                 :    2535460 :       if (nb)
    3952                 :            :         {
    3953                 :     476167 :           nb->aux = bb->aux;
    3954                 :     476167 :           bb->aux = nb;
    3955                 :            :           /* Don't process this new block.  */
    3956                 :     476167 :           bb = nb;
    3957                 :            :         }
    3958                 :            :     }
    3959                 :            : 
    3960                 :    1630610 :   relink_block_chain (/*stay_in_cfglayout_mode=*/false);
    3961                 :            : 
    3962                 :            :   /* Annoying special case - jump around dead jumptables left in the code.  */
    3963                 :   17413500 :   FOR_EACH_BB_FN (bb, cfun)
    3964                 :            :     {
    3965                 :   15782900 :       edge e = find_fallthru_edge (bb->succs);
    3966                 :            : 
    3967                 :   15782900 :       if (e && !can_fallthru (e->src, e->dest))
    3968                 :      43426 :         force_nonfallthru (e);
    3969                 :            :     }
    3970                 :            : 
    3971                 :            :   /* Ensure goto_locus from edges has some instructions with that locus in RTL
    3972                 :            :      when not optimizing.  */
    3973                 :    1630610 :   if (!optimize && !DECL_IGNORED_P (current_function_decl))
    3974                 :    2342440 :     FOR_EACH_BB_FN (bb, cfun)
    3975                 :            :       {
    3976                 :    2088220 :         edge e;
    3977                 :    2088220 :         edge_iterator ei;
    3978                 :            : 
    3979                 :    4961660 :         FOR_EACH_EDGE (e, ei, bb->succs)
    3980                 :    2873440 :           if (LOCATION_LOCUS (e->goto_locus) != UNKNOWN_LOCATION
    3981                 :    2873440 :               && !(e->flags & EDGE_ABNORMAL))
    3982                 :            :             {
    3983                 :     394618 :               edge e2;
    3984                 :     394618 :               edge_iterator ei2;
    3985                 :     394618 :               basic_block dest, nb;
    3986                 :     394618 :               rtx_insn *end;
    3987                 :            : 
    3988                 :     394618 :               insn = BB_END (e->src);
    3989                 :     394618 :               end = PREV_INSN (BB_HEAD (e->src));
    3990                 :     440462 :               while (insn != end
    3991                 :     834927 :                      && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn)))
    3992                 :      45844 :                 insn = PREV_INSN (insn);
    3993                 :     625389 :               if (insn != end
    3994                 :     394618 :                   && INSN_LOCATION (insn) == e->goto_locus)
    3995                 :     253834 :                 continue;
    3996                 :     163847 :               if (simplejump_p (BB_END (e->src))
    3997                 :     163847 :                   && !INSN_HAS_LOCATION (BB_END (e->src)))
    3998                 :            :                 {
    3999                 :          0 :                   INSN_LOCATION (BB_END (e->src)) = e->goto_locus;
    4000                 :          0 :                   continue;
    4001                 :            :                 }
    4002                 :     163847 :               dest = e->dest;
    4003                 :     163847 :               if (dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
    4004                 :            :                 {
    4005                 :            :                   /* Non-fallthru edges to the exit block cannot be split.  */
    4006                 :      70955 :                   if (!(e->flags & EDGE_FALLTHRU))
    4007                 :          0 :                     continue;
    4008                 :            :                 }
    4009                 :            :               else
    4010                 :            :                 {
    4011                 :      92892 :                   insn = BB_HEAD (dest);
    4012                 :      92892 :                   end = NEXT_INSN (BB_END (dest));
    4013                 :     276250 :                   while (insn != end && !NONDEBUG_INSN_P (insn))
    4014                 :     183358 :                     insn = NEXT_INSN (insn);
    4015                 :      51718 :                   if (insn != end && INSN_HAS_LOCATION (insn)
    4016                 :     144369 :                       && INSN_LOCATION (insn) == e->goto_locus)
    4017                 :      23063 :                     continue;
    4018                 :            :                 }
    4019                 :     140784 :               nb = split_edge (e);
    4020                 :     140784 :               if (!INSN_P (BB_END (nb)))
    4021                 :     140784 :                 BB_END (nb) = emit_insn_after_noloc (gen_nop (), BB_END (nb),
    4022                 :            :                                                          nb);
    4023                 :     140784 :               INSN_LOCATION (BB_END (nb)) = e->goto_locus;
    4024                 :            : 
    4025                 :            :               /* If there are other incoming edges to the destination block
    4026                 :            :                  with the same goto locus, redirect them to the new block as
    4027                 :            :                  well, this can prevent other such blocks from being created
    4028                 :            :                  in subsequent iterations of the loop.  */
    4029                 :   33959700 :               for (ei2 = ei_start (dest->preds); (e2 = ei_safe_edge (ei2)); )
    4030                 :   33818900 :                 if (LOCATION_LOCUS (e2->goto_locus) != UNKNOWN_LOCATION
    4031                 :   16890300 :                     && !(e2->flags & (EDGE_ABNORMAL | EDGE_FALLTHRU))
    4032                 :   50709200 :                     && e->goto_locus == e2->goto_locus)
    4033                 :      54989 :                   redirect_edge_and_branch (e2, nb);
    4034                 :            :                 else
    4035                 :   33763900 :                   ei_next (&ei2);
    4036                 :            :             }
    4037                 :            :       }
    4038                 :    1630610 : }
    4039                 :            : 
    4040                 :            : /* Perform sanity checks on the insn chain.
    4041                 :            :    1. Check that next/prev pointers are consistent in both the forward and
    4042                 :            :       reverse direction.
    4043                 :            :    2. Count insns in chain, going both directions, and check if equal.
    4044                 :            :    3. Check that get_last_insn () returns the actual end of chain.  */
    4045                 :            : 
    4046                 :            : DEBUG_FUNCTION void
    4047                 :    3261170 : verify_insn_chain (void)
    4048                 :            : {
    4049                 :    3261170 :   rtx_insn *x, *prevx, *nextx;
    4050                 :    3261170 :   int insn_cnt1, insn_cnt2;
    4051                 :            : 
    4052                 :    3261170 :   for (prevx = NULL, insn_cnt1 = 1, x = get_insns ();
    4053                 :  374927000 :        x != 0;
    4054                 :  371666000 :        prevx = x, insn_cnt1++, x = NEXT_INSN (x))
    4055                 :  371666000 :     gcc_assert (PREV_INSN (x) == prevx);
    4056                 :            : 
    4057                 :    3261170 :   gcc_assert (prevx == get_last_insn ());
    4058                 :            : 
    4059                 :  371666000 :   for (nextx = NULL, insn_cnt2 = 1, x = get_last_insn ();
    4060                 :  374927000 :        x != 0;
    4061                 :  371666000 :        nextx = x, insn_cnt2++, x = PREV_INSN (x))
    4062                 :  371666000 :     gcc_assert (NEXT_INSN (x) == nextx);
    4063                 :            : 
    4064                 :    3261170 :   gcc_assert (insn_cnt1 == insn_cnt2);
    4065                 :    3261170 : }
    4066                 :            : 
    4067                 :            : /* If we have assembler epilogues, the block falling through to exit must
    4068                 :            :    be the last one in the reordered chain when we reach final.  Ensure
    4069                 :            :    that this condition is met.  */
    4070                 :            : static void
    4071                 :          0 : fixup_fallthru_exit_predecessor (void)
    4072                 :            : {
    4073                 :          0 :   edge e;
    4074                 :          0 :   basic_block bb = NULL;
    4075                 :            : 
    4076                 :            :   /* This transformation is not valid before reload, because we might
    4077                 :            :      separate a call from the instruction that copies the return
    4078                 :            :      value.  */
    4079                 :          0 :   gcc_assert (reload_completed);
    4080                 :            : 
    4081                 :          0 :   e = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
    4082                 :          0 :   if (e)
    4083                 :          0 :     bb = e->src;
    4084                 :            : 
    4085                 :          0 :   if (bb && bb->aux)
    4086                 :            :     {
    4087                 :          0 :       basic_block c = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb;
    4088                 :            : 
    4089                 :            :       /* If the very first block is the one with the fall-through exit
    4090                 :            :          edge, we have to split that block.  */
    4091                 :          0 :       if (c == bb)
    4092                 :            :         {
    4093                 :          0 :           bb = split_block_after_labels (bb)->dest;
    4094                 :          0 :           bb->aux = c->aux;
    4095                 :          0 :           c->aux = bb;
    4096                 :          0 :           BB_FOOTER (bb) = BB_FOOTER (c);
    4097                 :          0 :           BB_FOOTER (c) = NULL;
    4098                 :            :         }
    4099                 :            : 
    4100                 :          0 :       while (c->aux != bb)
    4101                 :            :         c = (basic_block) c->aux;
    4102                 :            : 
    4103                 :          0 :       c->aux = bb->aux;
    4104                 :          0 :       while (c->aux)
    4105                 :            :         c = (basic_block) c->aux;
    4106                 :            : 
    4107                 :          0 :       c->aux = bb;
    4108                 :          0 :       bb->aux = NULL;
    4109                 :            :     }
    4110                 :          0 : }
    4111                 :            : 
    4112                 :            : /* In case there are more than one fallthru predecessors of exit, force that
    4113                 :            :    there is only one.  */
    4114                 :            : 
    4115                 :            : static void
    4116                 :    1630610 : force_one_exit_fallthru (void)
    4117                 :            : {
    4118                 :    1630610 :   edge e, predecessor = NULL;
    4119                 :    1630610 :   bool more = false;
    4120                 :    1630610 :   edge_iterator ei;
    4121                 :    1630610 :   basic_block forwarder, bb;
    4122                 :            : 
    4123                 :    3425240 :   FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
    4124                 :    1794640 :     if (e->flags & EDGE_FALLTHRU)
    4125                 :            :       {
    4126                 :     870395 :         if (predecessor == NULL)
    4127                 :            :           predecessor = e;
    4128                 :            :         else
    4129                 :            :           {
    4130                 :            :             more = true;
    4131                 :            :             break;
    4132                 :            :           }
    4133                 :            :       }
    4134                 :            : 
    4135                 :    1630610 :   if (!more)
    4136                 :    1630610 :     return;
    4137                 :            : 
    4138                 :            :   /* Exit has several fallthru predecessors.  Create a forwarder block for
    4139                 :            :      them.  */
    4140                 :          1 :   forwarder = split_edge (predecessor);
    4141                 :          1 :   for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
    4142                 :          3 :        (e = ei_safe_edge (ei)); )
    4143                 :            :     {
    4144                 :          2 :       if (e->src == forwarder
    4145                 :          1 :           || !(e->flags & EDGE_FALLTHRU))
    4146                 :          1 :         ei_next (&ei);
    4147                 :            :       else
    4148                 :          1 :         redirect_edge_and_branch_force (e, forwarder);
    4149                 :            :     }
    4150                 :            : 
    4151                 :            :   /* Fix up the chain of blocks -- make FORWARDER immediately precede the
    4152                 :            :      exit block.  */
    4153                 :          5 :   FOR_EACH_BB_FN (bb, cfun)
    4154                 :            :     {
    4155                 :          5 :       if (bb->aux == NULL && bb != forwarder)
    4156                 :            :         {
    4157                 :          1 :           bb->aux = forwarder;
    4158                 :          1 :           break;
    4159                 :            :         }
    4160                 :            :     }
    4161                 :            : }
    4162                 :            : 
    4163                 :            : /* Return true in case it is possible to duplicate the basic block BB.  */
    4164                 :            : 
    4165                 :            : static bool
    4166                 :    3093600 : cfg_layout_can_duplicate_bb_p (const_basic_block bb)
    4167                 :            : {
    4168                 :            :   /* Do not attempt to duplicate tablejumps, as we need to unshare
    4169                 :            :      the dispatch table.  This is difficult to do, as the instructions
    4170                 :            :      computing jump destination may be hoisted outside the basic block.  */
    4171                 :    3093600 :   if (tablejump_p (BB_END (bb), NULL, NULL))
    4172                 :            :     return false;
    4173                 :            : 
    4174                 :            :   /* Do not duplicate blocks containing insns that can't be copied.  */
    4175                 :    3093440 :   if (targetm.cannot_copy_insn_p)
    4176                 :            :     {
    4177                 :          0 :       rtx_insn *insn = BB_HEAD (bb);
    4178                 :          0 :       while (1)
    4179                 :            :         {
    4180                 :          0 :           if (INSN_P (insn) && targetm.cannot_copy_insn_p (insn))
    4181                 :            :             return false;
    4182                 :          0 :           if (insn == BB_END (bb))
    4183                 :            :             break;
    4184                 :          0 :           insn = NEXT_INSN (insn);
    4185                 :            :         }
    4186                 :            :     }
    4187                 :            : 
    4188                 :            :   return true;
    4189                 :            : }
    4190                 :            : 
    4191                 :            : rtx_insn *
    4192                 :     445510 : duplicate_insn_chain (rtx_insn *from, rtx_insn *to)
    4193                 :            : {
    4194                 :     445510 :   rtx_insn *insn, *next, *copy;
    4195                 :     445510 :   rtx_note *last;
    4196                 :            : 
    4197                 :            :   /* Avoid updating of boundaries of previous basic block.  The
    4198                 :            :      note will get removed from insn stream in fixup.  */
    4199                 :     445510 :   last = emit_note (NOTE_INSN_DELETED);
    4200                 :            : 
    4201                 :            :   /* Create copy at the end of INSN chain.  The chain will
    4202                 :            :      be reordered later.  */
    4203                 :    6025050 :   for (insn = from; insn != NEXT_INSN (to); insn = NEXT_INSN (insn))
    4204                 :            :     {
    4205                 :    2789770 :       switch (GET_CODE (insn))
    4206                 :            :         {
    4207                 :     612507 :         case DEBUG_INSN:
    4208                 :            :           /* Don't duplicate label debug insns.  */
    4209                 :     612507 :           if (DEBUG_BIND_INSN_P (insn)
    4210                 :    1107210 :               && TREE_CODE (INSN_VAR_LOCATION_DECL (insn)) == LABEL_DECL)
    4211                 :            :             break;
    4212                 :            :           /* FALLTHRU */
    4213                 :    1914040 :         case INSN:
    4214                 :    1914040 :         case CALL_INSN:
    4215                 :    1914040 :         case JUMP_INSN:
    4216                 :    1914040 :           copy = emit_copy_of_insn_after (insn, get_last_insn ());
    4217                 :    1914040 :           if (JUMP_P (insn) && JUMP_LABEL (insn) != NULL_RTX
    4218                 :     241279 :               && ANY_RETURN_P (JUMP_LABEL (insn)))
    4219                 :      97054 :             JUMP_LABEL (copy) = JUMP_LABEL (insn);
    4220                 :    1914040 :           maybe_copy_prologue_epilogue_insn (insn, copy);
    4221                 :    1914040 :           break;
    4222                 :            : 
    4223                 :          0 :         case JUMP_TABLE_DATA:
    4224                 :            :           /* Avoid copying of dispatch tables.  We never duplicate
    4225                 :            :              tablejumps, so this can hit only in case the table got
    4226                 :            :              moved far from original jump.
    4227                 :            :              Avoid copying following barrier as well if any
    4228                 :            :              (and debug insns in between).  */
    4229                 :          0 :           for (next = NEXT_INSN (insn);
    4230                 :          0 :                next != NEXT_INSN (to);
    4231                 :          0 :                next = NEXT_INSN (next))
    4232                 :          0 :             if (!DEBUG_INSN_P (next))
    4233                 :            :               break;
    4234                 :          0 :           if (next != NEXT_INSN (to) && BARRIER_P (next))
    4235                 :          0 :             insn = next;
    4236                 :            :           break;
    4237                 :            : 
    4238                 :            :         case CODE_LABEL:
    4239                 :            :           break;
    4240                 :            : 
    4241                 :      97814 :         case BARRIER:
    4242                 :      97814 :           emit_barrier ();
    4243                 :      97814 :           break;
    4244                 :            : 
    4245                 :     468020 :         case NOTE:
    4246                 :     468020 :           switch (NOTE_KIND (insn))
    4247                 :            :             {
    4248                 :            :               /* In case prologue is empty and function contain label
    4249                 :            :                  in first BB, we may want to copy the block.  */
    4250                 :            :             case NOTE_INSN_PROLOGUE_END:
    4251                 :            : 
    4252                 :            :             case NOTE_INSN_DELETED:
    4253                 :            :             case NOTE_INSN_DELETED_LABEL:
    4254                 :            :             case NOTE_INSN_DELETED_DEBUG_LABEL:
    4255                 :            :               /* No problem to strip these.  */
    4256                 :            :             case NOTE_INSN_FUNCTION_BEG:
    4257                 :            :               /* There is always just single entry to function.  */
    4258                 :            :             case NOTE_INSN_BASIC_BLOCK:
    4259                 :            :               /* We should only switch text sections once.  */
    4260                 :            :             case NOTE_INSN_SWITCH_TEXT_SECTIONS:
    4261                 :            :               break;
    4262                 :            : 
    4263                 :      96618 :             case NOTE_INSN_EPILOGUE_BEG:
    4264                 :      96618 :             case NOTE_INSN_UPDATE_SJLJ_CONTEXT:
    4265                 :      96618 :               emit_note_copy (as_a <rtx_note *> (insn));
    4266                 :      96618 :               break;
    4267                 :            : 
    4268                 :          0 :             default:
    4269                 :            :               /* All other notes should have already been eliminated.  */
    4270                 :          0 :               gcc_unreachable ();
    4271                 :            :             }
    4272                 :            :           break;
    4273                 :          0 :         default:
    4274                 :          0 :           gcc_unreachable ();
    4275                 :            :         }
    4276                 :            :     }
    4277                 :     445510 :   insn = NEXT_INSN (last);
    4278                 :     445510 :   delete_insn (last);
    4279                 :     445510 :   return insn;
    4280                 :            : }
    4281                 :            : 
    4282                 :            : /* Create a duplicate of the basic block BB.  */
    4283                 :            : 
    4284                 :            : static basic_block
    4285                 :     347511 : cfg_layout_duplicate_bb (basic_block bb, copy_bb_data *)
    4286                 :            : {
    4287                 :     347511 :   rtx_insn *insn;
    4288                 :     347511 :   basic_block new_bb;
    4289                 :            : 
    4290                 :     347511 :   insn = duplicate_insn_chain (BB_HEAD (bb), BB_END (bb));
    4291                 :     347511 :   new_bb = create_basic_block (insn,
    4292                 :            :                                insn ? get_last_insn () : NULL,
    4293                 :     347511 :                                EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb);
    4294                 :            : 
    4295                 :     347511 :   BB_COPY_PARTITION (new_bb, bb);
    4296                 :     347511 :   if (BB_HEADER (bb))
    4297                 :            :     {
    4298                 :            :       insn = BB_HEADER (bb);
    4299                 :        235 :       while (NEXT_INSN (insn))
    4300                 :        235 :         insn = NEXT_INSN (insn);
    4301                 :        235 :       insn = duplicate_insn_chain (BB_HEADER (bb), insn);
    4302                 :        235 :       if (insn)
    4303                 :          0 :         BB_HEADER (new_bb) = unlink_insn_chain (insn, get_last_insn ());
    4304                 :            :     }
    4305                 :            : 
    4306                 :     347511 :   if (BB_FOOTER (bb))
    4307                 :            :     {
    4308                 :            :       insn = BB_FOOTER (bb);
    4309                 :      97816 :       while (NEXT_INSN (insn))
    4310                 :      97816 :         insn = NEXT_INSN (insn);
    4311                 :      97764 :       insn = duplicate_insn_chain (BB_FOOTER (bb), insn);
    4312                 :      97764 :       if (insn)
    4313                 :      97763 :         BB_FOOTER (new_bb) = unlink_insn_chain (insn, get_last_insn ());
    4314                 :            :     }
    4315                 :            : 
    4316                 :     347511 :   return new_bb;
    4317                 :            : }
    4318                 :            : 
    4319                 :            : 
    4320                 :            : /* Main entry point to this module - initialize the datastructures for
    4321                 :            :    CFG layout changes.  It keeps LOOPS up-to-date if not null.
    4322                 :            : 
    4323                 :            :    FLAGS is a set of additional flags to pass to cleanup_cfg().  */
    4324                 :            : 
    4325                 :            : void
    4326                 :    1630610 : cfg_layout_initialize (int flags)
    4327                 :            : {
    4328                 :    1630610 :   rtx_insn_list *x;
    4329                 :    1630610 :   basic_block bb;
    4330                 :            : 
    4331                 :            :   /* Once bb partitioning is complete, cfg layout mode should not be
    4332                 :            :      re-entered.  Entering cfg layout mode may require fixups.  As an
    4333                 :            :      example, if edge forwarding performed when optimizing the cfg
    4334                 :            :      layout required moving a block from the hot to the cold
    4335                 :            :      section. This would create an illegal partitioning unless some
    4336                 :            :      manual fixup was performed.  */
    4337                 :    1630610 :   gcc_assert (!crtl->bb_reorder_complete || !crtl->has_bb_partition);
    4338                 :            : 
    4339                 :    1630610 :   initialize_original_copy_tables ();
    4340                 :            : 
    4341                 :    1630610 :   cfg_layout_rtl_register_cfg_hooks ();
    4342                 :            : 
    4343                 :    1630610 :   record_effective_endpoints ();
    4344                 :            : 
    4345                 :            :   /* Make sure that the targets of non local gotos are marked.  */
    4346                 :    1631480 :   for (x = nonlocal_goto_handler_labels; x; x = x->next ())
    4347                 :            :     {
    4348                 :       2310 :       bb = BLOCK_FOR_INSN (x->insn ());
    4349                 :       2310 :       bb->flags |= BB_NON_LOCAL_GOTO_TARGET;
    4350                 :            :     }
    4351                 :            : 
    4352                 :    1630610 :   cleanup_cfg (CLEANUP_CFGLAYOUT | flags);
    4353                 :    1630610 : }
    4354                 :            : 
    4355                 :            : /* Splits superblocks.  */
    4356                 :            : void
    4357                 :      42934 : break_superblocks (void)
    4358                 :            : {
    4359                 :      42934 :   bool need = false;
    4360                 :      42934 :   basic_block bb;
    4361                 :            : 
    4362                 :      42934 :   auto_sbitmap superblocks (last_basic_block_for_fn (cfun));
    4363                 :      42934 :   bitmap_clear (superblocks);
    4364                 :            : 
    4365                 :    2153860 :   FOR_EACH_BB_FN (bb, cfun)
    4366                 :    2110930 :     if (bb->flags & BB_SUPERBLOCK)
    4367                 :            :       {
    4368                 :     154914 :         bb->flags &= ~BB_SUPERBLOCK;
    4369                 :     154914 :         bitmap_set_bit (superblocks, bb->index);
    4370                 :     154914 :         need = true;
    4371                 :            :       }
    4372                 :            : 
    4373                 :      42934 :   if (need)
    4374                 :            :     {
    4375                 :      35632 :       rebuild_jump_labels (get_insns ());
    4376                 :      35632 :       find_many_sub_basic_blocks (superblocks);
    4377                 :            :     }
    4378                 :      42934 : }
    4379                 :            : 
    4380                 :            : /* Finalize the changes: reorder insn list according to the sequence specified
    4381                 :            :    by aux pointers, enter compensation code, rebuild scope forest.  */
    4382                 :            : 
    4383                 :            : void
    4384                 :    1630610 : cfg_layout_finalize (void)
    4385                 :            : {
    4386                 :    1630610 :   free_dominance_info (CDI_DOMINATORS);
    4387                 :    1630610 :   force_one_exit_fallthru ();
    4388                 :    1630610 :   rtl_register_cfg_hooks ();
    4389                 :    1630610 :   if (reload_completed && !targetm.have_epilogue ())
    4390                 :          0 :     fixup_fallthru_exit_predecessor ();
    4391                 :    1630610 :   fixup_reorder_chain ();
    4392                 :            : 
    4393                 :    1630610 :   rebuild_jump_labels (get_insns ());
    4394                 :    1630610 :   delete_dead_jumptables ();
    4395                 :            : 
    4396                 :    1630610 :   if (flag_checking)
    4397                 :    1630580 :     verify_insn_chain ();
    4398                 :    1630610 :   checking_verify_flow_info ();
    4399                 :    1630610 : }
    4400                 :            : 
    4401                 :            : 
    4402                 :            : /* Same as split_block but update cfg_layout structures.  */
    4403                 :            : 
    4404                 :            : static basic_block
    4405                 :       6355 : cfg_layout_split_block (basic_block bb, void *insnp)
    4406                 :            : {
    4407                 :       6355 :   rtx insn = (rtx) insnp;
    4408                 :       6355 :   basic_block new_bb = rtl_split_block (bb, insn);
    4409                 :            : 
    4410                 :       6355 :   BB_FOOTER (new_bb) = BB_FOOTER (bb);
    4411                 :       6355 :   BB_FOOTER (bb) = NULL;
    4412                 :            : 
    4413                 :       6355 :   return new_bb;
    4414                 :            : }
    4415                 :            : 
    4416                 :            : /* Redirect Edge to DEST.  */
    4417                 :            : static edge
    4418                 :    5803550 : cfg_layout_redirect_edge_and_branch (edge e, basic_block dest)
    4419                 :            : {
    4420                 :    5803550 :   basic_block src = e->src;
    4421                 :    5803550 :   edge ret;
    4422                 :            : 
    4423                 :    5803550 :   if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
    4424                 :            :     return NULL;
    4425                 :            : 
    4426                 :    5803550 :   if (e->dest == dest)
    4427                 :            :     return e;
    4428                 :            : 
    4429                 :    5803550 :   if (e->flags & EDGE_CROSSING
    4430                 :          7 :       && BB_PARTITION (e->src) == BB_PARTITION (dest)
    4431                 :    5803550 :       && simplejump_p (BB_END (src)))
    4432                 :            :     {
    4433                 :          0 :       if (dump_file)
    4434                 :          0 :         fprintf (dump_file,
    4435                 :            :                  "Removing crossing jump while redirecting edge form %i to %i\n",
    4436                 :          0 :                  e->src->index, dest->index);
    4437                 :          0 :       delete_insn (BB_END (src));
    4438                 :          0 :       remove_barriers_from_footer (src);
    4439                 :          0 :       e->flags |= EDGE_FALLTHRU;
    4440                 :            :     }
    4441                 :            : 
    4442                 :    5803550 :   if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
    4443                 :    5803550 :       && (ret = try_redirect_by_replacing_jump (e, dest, true)))
    4444                 :            :     {
    4445                 :     155166 :       df_set_bb_dirty (src);
    4446                 :     155166 :       return ret;
    4447                 :            :     }
    4448                 :            : 
    4449                 :    5648380 :   if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun)
    4450                 :          0 :       && (e->flags & EDGE_FALLTHRU) && !(e->flags & EDGE_COMPLEX))
    4451                 :            :     {
    4452                 :          0 :       if (dump_file)
    4453                 :          0 :         fprintf (dump_file, "Redirecting entry edge from bb %i to %i\n",
    4454                 :            :                  e->src->index, dest->index);
    4455                 :            : 
    4456                 :          0 :       df_set_bb_dirty (e->src);
    4457                 :          0 :       redirect_edge_succ (e, dest);
    4458                 :          0 :       return e;
    4459                 :            :     }
    4460                 :            : 
    4461                 :            :   /* Redirect_edge_and_branch may decide to turn branch into fallthru edge
    4462                 :            :      in the case the basic block appears to be in sequence.  Avoid this
    4463                 :            :      transformation.  */
    4464                 :            : 
    4465                 :    5648380 :   if (e->flags & EDGE_FALLTHRU)
    4466                 :            :     {
    4467                 :            :       /* Redirect any branch edges unified with the fallthru one.  */
    4468                 :    2750410 :       if (JUMP_P (BB_END (src))
    4469                 :    2750410 :           && label_is_jump_target_p (BB_HEAD (e->dest),
    4470                 :            :                                      BB_END (src)))
    4471                 :            :         {
    4472                 :         36 :           edge redirected;
    4473                 :            : 
    4474                 :         36 :           if (dump_file)
    4475                 :          0 :             fprintf (dump_file, "Fallthru edge unified with branch "
    4476                 :            :                      "%i->%i redirected to %i\n",
    4477                 :          0 :                      e->src->index, e->dest->index, dest->index);
    4478                 :         36 :           e->flags &= ~EDGE_FALLTHRU;
    4479                 :         36 :           redirected = redirect_branch_edge (e, dest);
    4480                 :         36 :           gcc_assert (redirected);
    4481                 :         36 :           redirected->flags |= EDGE_FALLTHRU;
    4482                 :         36 :           df_set_bb_dirty (redirected->src);
    4483                 :         36 :           return redirected;
    4484                 :            :         }
    4485                 :            :       /* In case we are redirecting fallthru edge to the branch edge
    4486                 :            :          of conditional jump, remove it.  */
    4487                 :    2750370 :       if (EDGE_COUNT (src->succs) == 2)
    4488                 :            :         {
    4489                 :            :           /* Find the edge that is different from E.  */
    4490                 :    2201150 :           edge s = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e);
    4491                 :            : 
    4492                 :    2201150 :           if (s->dest == dest
    4493                 :          9 :               && any_condjump_p (BB_END (src))
    4494                 :    2201150 :               && onlyjump_p (BB_END (src)))
    4495                 :          0 :             delete_insn (BB_END (src));
    4496                 :            :         }
    4497                 :    2750370 :       if (dump_file)
    4498                 :       2476 :         fprintf (dump_file, "Redirecting fallthru edge %i->%i to %i\n",
    4499                 :       2476 :                  e->src->index, e->dest->index, dest->index);
    4500                 :    2750370 :       ret = redirect_edge_succ_nodup (e, dest);
    4501                 :            :     }
    4502                 :            :   else
    4503                 :    2897980 :     ret = redirect_branch_edge (e, dest);
    4504                 :            : 
    4505                 :    5648340 :   if (!ret)
    4506                 :            :     return NULL;
    4507                 :            : 
    4508                 :    5648340 :   fixup_partition_crossing (ret);
    4509                 :            :   /* We don't want simplejumps in the insn stream during cfglayout.  */
    4510                 :    5648340 :   gcc_assert (!simplejump_p (BB_END (src)) || CROSSING_JUMP_P (BB_END (src)));
    4511                 :            : 
    4512                 :    5648340 :   df_set_bb_dirty (src);
    4513                 :    5648340 :   return ret;
    4514                 :            : }
    4515                 :            : 
    4516                 :            : /* Simple wrapper as we always can redirect fallthru edges.  */
    4517                 :            : static basic_block
    4518                 :    2681870 : cfg_layout_redirect_edge_and_branch_force (edge e, basic_block dest)
    4519                 :            : {
    4520                 :    2681870 :   edge redirected = cfg_layout_redirect_edge_and_branch (e, dest);
    4521                 :            : 
    4522                 :    2681870 :   gcc_assert (redirected);
    4523                 :    2681870 :   return NULL;
    4524                 :            : }
    4525                 :            : 
    4526                 :            : /* Same as delete_basic_block but update cfg_layout structures.  */
    4527                 :            : 
    4528                 :            : static void
    4529                 :    3326430 : cfg_layout_delete_block (basic_block bb)
    4530                 :            : {
    4531                 :    3326430 :   rtx_insn *insn, *next, *prev = PREV_INSN (BB_HEAD (bb)), *remaints;
    4532                 :    3326430 :   rtx_insn **to;
    4533                 :            : 
    4534                 :    3326430 :   if (BB_HEADER (bb))
    4535                 :            :     {
    4536                 :         27 :       next = BB_HEAD (bb);
    4537                 :         27 :       if (prev)
    4538                 :         27 :         SET_NEXT_INSN (prev) = BB_HEADER (bb);
    4539                 :            :       else
    4540                 :          0 :         set_first_insn (BB_HEADER (bb));
    4541                 :         27 :       SET_PREV_INSN (BB_HEADER (bb)) = prev;
    4542                 :         27 :       insn = BB_HEADER (bb);
    4543                 :         27 :       while (NEXT_INSN (insn))
    4544                 :         27 :         insn = NEXT_INSN (insn);
    4545                 :         27 :       SET_NEXT_INSN (insn) = next;
    4546                 :         27 :       SET_PREV_INSN (next) = insn;
    4547                 :            :     }
    4548                 :    3326430 :   next = NEXT_INSN (BB_END (bb));
    4549                 :    3326430 :   if (BB_FOOTER (bb))
    4550                 :            :     {
    4551                 :            :       insn = BB_FOOTER (bb);
    4552                 :    1873810 :       while (insn)
    4553                 :            :         {
    4554                 :     936905 :           if (BARRIER_P (insn))
    4555                 :            :             {
    4556                 :     936904 :               if (PREV_INSN (insn))
    4557                 :          1 :                 SET_NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn);
    4558                 :            :               else
    4559                 :     936903 :                 BB_FOOTER (bb) = NEXT_INSN (insn);
    4560                 :     936904 :               if (NEXT_INSN (insn))
    4561                 :          1 :                 SET_PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn);
    4562                 :            :             }
    4563                 :     936905 :           if (LABEL_P (insn))
    4564                 :            :             break;
    4565                 :     936905 :           insn = NEXT_INSN (insn);
    4566                 :            :         }
    4567                 :     936903 :       if (BB_FOOTER (bb))
    4568                 :            :         {
    4569                 :          1 :           insn = BB_END (bb);
    4570                 :          1 :           SET_NEXT_INSN (insn) = BB_FOOTER (bb);
    4571                 :          1 :           SET_PREV_INSN (BB_FOOTER (bb)) = insn;
    4572                 :          2 :           while (NEXT_INSN (insn))
    4573                 :          2 :             insn = NEXT_INSN (insn);
    4574                 :          1 :           SET_NEXT_INSN (insn) = next;
    4575                 :          1 :           if (next)
    4576                 :          0 :             SET_PREV_INSN (next) = insn;
    4577                 :            :           else
    4578                 :          1 :             set_last_insn (insn);
    4579                 :            :         }
    4580                 :            :     }
    4581                 :    3326430 :   if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun))
    4582                 :    3317250 :     to = &BB_HEADER (bb->next_bb);
    4583                 :            :   else
    4584                 :            :     to = &cfg_layout_function_footer;
    4585                 :            : 
    4586                 :    3326430 :   rtl_delete_block (bb);
    4587                 :            : 
    4588                 :    3326430 :   if (prev)
    4589                 :    3326430 :     prev = NEXT_INSN (prev);
    4590                 :            :   else
    4591                 :          0 :     prev = get_insns ();
    4592                 :    3326430 :   if (next)
    4593                 :    3317250 :     next = PREV_INSN (next);
    4594                 :            :   else
    4595                 :       9177 :     next = get_last_insn ();
    4596                 :            : 
    4597                 :    3326430 :   if (next && NEXT_INSN (next) != prev)
    4598                 :            :     {
    4599                 :        267 :       remaints = unlink_insn_chain (prev, next);
    4600                 :        267 :       insn = remaints;
    4601                 :        359 :       while (NEXT_INSN (insn))
    4602                 :        359 :         insn = NEXT_INSN (insn);
    4603                 :        267 :       SET_NEXT_INSN (insn) = *to;
    4604                 :        267 :       if (*to)
    4605                 :         18 :         SET_PREV_INSN (*to) = insn;
    4606                 :        267 :       *to = remaints;
    4607                 :            :     }
    4608                 :    3326430 : }
    4609                 :            : 
    4610                 :            : /* Return true when blocks A and B can be safely merged.  */
    4611                 :            : 
    4612                 :            : static bool
    4613                 :    1959820 : cfg_layout_can_merge_blocks_p (basic_block a, basic_block b)
    4614                 :            : {
    4615                 :            :   /* If we are partitioning hot/cold basic blocks, we don't want to
    4616                 :            :      mess up unconditional or indirect jumps that cross between hot
    4617                 :            :      and cold sections.
    4618                 :            : 
    4619                 :            :      Basic block partitioning may result in some jumps that appear to
    4620                 :            :      be optimizable (or blocks that appear to be mergeable), but which really
    4621                 :            :      must be left untouched (they are required to make it safely across
    4622                 :            :      partition boundaries).  See  the comments at the top of
    4623                 :            :      bb-reorder.c:partition_hot_cold_basic_blocks for complete details.  */
    4624                 :            : 
    4625                 :    1959820 :   if (BB_PARTITION (a) != BB_PARTITION (b))
    4626                 :            :     return false;
    4627                 :            : 
    4628                 :            :   /* Protect the loop latches.  */
    4629                 :    1855670 :   if (current_loops && b->loop_father->latch == b)
    4630                 :            :     return false;
    4631                 :            : 
    4632                 :            :   /* If we would end up moving B's instructions, make sure it doesn't fall
    4633                 :            :      through into the exit block, since we cannot recover from a fallthrough
    4634                 :            :      edge into the exit block occurring in the middle of a function.  */
    4635                 :    1576710 :   if (NEXT_INSN (BB_END (a)) != BB_HEAD (b))
    4636                 :            :     {
    4637                 :    1021160 :       edge e = find_fallthru_edge (b->succs);
    4638                 :    1021160 :       if (e && e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
    4639                 :            :         return false;
    4640                 :            :     }
    4641                 :            : 
    4642                 :            :   /* There must be exactly one edge in between the blocks.  */
    4643                 :    1018800 :   return (single_succ_p (a)
    4644                 :    1018800 :           && single_succ (a) == b
    4645                 :    1018800 :           && single_pred_p (b) == 1
    4646                 :    1004500 :           && a != b
    4647                 :            :           /* Must be simple edge.  */
    4648                 :    1004500 :           && !(single_succ_edge (a)->flags & EDGE_COMPLEX)
    4649                 :    1004500 :           && a != ENTRY_BLOCK_PTR_FOR_FN (cfun)
    4650                 :    1004500 :           && b != EXIT_BLOCK_PTR_FOR_FN (cfun)
    4651                 :            :           /* If the jump insn has side effects, we can't kill the edge.
    4652                 :            :              When not optimizing, try_redirect_by_replacing_jump will
    4653                 :            :              not allow us to redirect an edge by replacing a table jump.  */
    4654                 :    2023300 :           && (!JUMP_P (BB_END (a))
    4655                 :      77566 :               || ((!optimize || reload_completed)
    4656                 :      77566 :                   ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a)))));
    4657                 :            : }
    4658                 :            : 
    4659                 :            : /* Merge block A and B.  The blocks must be mergeable.  */
    4660                 :            : 
    4661                 :            : static void
    4662                 :     501399 : cfg_layout_merge_blocks (basic_block a, basic_block b)
    4663                 :            : {
    4664                 :            :   /* If B is a forwarder block whose outgoing edge has no location, we'll
    4665                 :            :      propagate the locus of the edge between A and B onto it.  */
    4666                 :     501399 :   const bool forward_edge_locus
    4667                 :     501399 :     = (b->flags & BB_FORWARDER_BLOCK) != 0
    4668                 :     501399 :       && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION;
    4669                 :     501399 :   rtx_insn *insn;
    4670                 :            : 
    4671                 :     501399 :   gcc_checking_assert (cfg_layout_can_merge_blocks_p (a, b));
    4672                 :            : 
    4673                 :     501399 :   if (dump_file)
    4674                 :         77 :     fprintf (dump_file, "Merging block %d into block %d...\n", b->index,
    4675                 :            :                          a->index);
    4676                 :            : 
    4677                 :            :   /* If there was a CODE_LABEL beginning B, delete it.  */
    4678                 :     501399 :   if (LABEL_P (BB_HEAD (b)))
    4679                 :            :     {
    4680                 :     211926 :       delete_insn (BB_HEAD (b));
    4681                 :            :     }
    4682                 :            : 
    4683                 :            :   /* We should have fallthru edge in a, or we can do dummy redirection to get
    4684                 :            :      it cleaned up.  */
    4685                 :     501399 :   if (JUMP_P (BB_END (a)))
    4686                 :      19679 :     try_redirect_by_replacing_jump (EDGE_SUCC (a, 0), b, true);
    4687                 :     501399 :   gcc_assert (!JUMP_P (BB_END (a)));
    4688                 :            : 
    4689                 :            :   /* If not optimizing, preserve the locus of the single edge between
    4690                 :            :      blocks A and B if necessary by emitting a nop.  */
    4691                 :     501399 :   if (!optimize
    4692                 :       2655 :       && !forward_edge_locus
    4693                 :     504011 :       && !DECL_IGNORED_P (current_function_decl))
    4694                 :       2612 :     emit_nop_for_unique_locus_between (a, b);
    4695                 :            : 
    4696                 :            :   /* Move things from b->footer after a->footer.  */
    4697                 :     501399 :   if (BB_FOOTER (b))
    4698                 :            :     {
    4699                 :     139040 :       if (!BB_FOOTER (a))
    4700                 :     139025 :         BB_FOOTER (a) = BB_FOOTER (b);
    4701                 :            :       else
    4702                 :            :         {
    4703                 :            :           rtx_insn *last = BB_FOOTER (a);
    4704                 :            : 
    4705                 :         15 :           while (NEXT_INSN (last))
    4706                 :         15 :             last = NEXT_INSN (last);
    4707                 :         15 :           SET_NEXT_INSN (last) = BB_FOOTER (b);
    4708                 :         15 :           SET_PREV_INSN (BB_FOOTER (b)) = last;
    4709                 :            :         }
    4710                 :     139040 :       BB_FOOTER (b) = NULL;
    4711                 :            :     }
    4712                 :            : 
    4713                 :            :   /* Move things from b->header before a->footer.
    4714                 :            :      Note that this may include dead tablejump data, but we don't clean
    4715                 :            :      those up until we go out of cfglayout mode.  */
    4716                 :     501399 :    if (BB_HEADER (b))
    4717                 :            :      {
    4718                 :        303 :       if (! BB_FOOTER (a))
    4719                 :        255 :         BB_FOOTER (a) = BB_HEADER (b);
    4720                 :            :       else
    4721                 :            :         {
    4722                 :            :           rtx_insn *last = BB_HEADER (b);
    4723                 :            :  
    4724                 :         48 :           while (NEXT_INSN (last))
    4725                 :         48 :             last = NEXT_INSN (last);
    4726                 :         48 :           SET_NEXT_INSN (last) = BB_FOOTER (a);
    4727                 :         48 :           SET_PREV_INSN (BB_FOOTER (a)) = last;
    4728                 :         48 :           BB_FOOTER (a) = BB_HEADER (b);
    4729                 :            :         }
    4730                 :        303 :       BB_HEADER (b) = NULL;
    4731                 :            :     }
    4732                 :            : 
    4733                 :            :   /* In the case basic blocks are not adjacent, move them around.  */
    4734                 :     501399 :   if (NEXT_INSN (BB_END (a)) != BB_HEAD (b))
    4735                 :            :     {
    4736                 :     229278 :       insn = unlink_insn_chain (BB_HEAD (b), BB_END (b));
    4737                 :            : 
    4738                 :     229278 :       emit_insn_after_noloc (insn, BB_END (a), a);
    4739                 :            :     }
    4740                 :            :   /* Otherwise just re-associate the instructions.  */
    4741                 :            :   else
    4742                 :            :     {
    4743                 :     272121 :       insn = BB_HEAD (b);
    4744                 :     272121 :       BB_END (a) = BB_END (b);
    4745                 :            :     }
    4746                 :            : 
    4747                 :            :   /* emit_insn_after_noloc doesn't call df_insn_change_bb.
    4748                 :            :      We need to explicitly call. */
    4749                 :     501399 :   update_bb_for_insn_chain (insn, BB_END (b), a);
    4750                 :            : 
    4751                 :            :   /* Skip possible DELETED_LABEL insn.  */
    4752                 :     501399 :   if (!NOTE_INSN_BASIC_BLOCK_P (insn))
    4753                 :          0 :     insn = NEXT_INSN (insn);
    4754                 :     501399 :   gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn));
    4755                 :     501399 :   BB_HEAD (b) = BB_END (b) = NULL;
    4756                 :     501399 :   delete_insn (insn);
    4757                 :            : 
    4758                 :     501399 :   df_bb_delete (b->index);
    4759                 :            : 
    4760                 :     501399 :   if (forward_edge_locus)
    4761                 :      94525 :     EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus;
    4762                 :            : 
    4763                 :     501399 :   if (dump_file)
    4764                 :         77 :     fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index);
    4765                 :     501399 : }
    4766                 :            : 
    4767                 :            : /* Split edge E.  */
    4768                 :            : 
    4769                 :            : static basic_block
    4770                 :    2031260 : cfg_layout_split_edge (edge e)
    4771                 :            : {
    4772                 :    2031260 :   basic_block new_bb =
    4773                 :    4062510 :     create_basic_block (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
    4774                 :    2031260 :                         ? NEXT_INSN (BB_END (e->src)) : get_insns (),
    4775                 :            :                         NULL_RTX, e->src);
    4776                 :            : 
    4777                 :    2031260 :   if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
    4778                 :          1 :     BB_COPY_PARTITION (new_bb, e->src);
    4779                 :            :   else
    4780                 :    2031250 :     BB_COPY_PARTITION (new_bb, e->dest);
    4781                 :    2031260 :   make_edge (new_bb, e->dest, EDGE_FALLTHRU);
    4782                 :    2031260 :   redirect_edge_and_branch_force (e, new_bb);
    4783                 :            : 
    4784                 :    2031260 :   return new_bb;
    4785                 :            : }
    4786                 :            : 
    4787                 :            : /* Do postprocessing after making a forwarder block joined by edge FALLTHRU.  */
    4788                 :            : 
    4789                 :            : static void
    4790                 :       1163 : rtl_make_forwarder_block (edge fallthru ATTRIBUTE_UNUSED)
    4791                 :            : {
    4792                 :       1163 : }
    4793                 :            : 
    4794                 :            : /* Return true if BB contains only labels or non-executable
    4795                 :            :    instructions.  */
    4796                 :            : 
    4797                 :            : static bool
    4798                 :          0 : rtl_block_empty_p (basic_block bb)
    4799                 :            : {
    4800                 :          0 :   rtx_insn *insn;
    4801                 :            : 
    4802                 :          0 :   if (bb == ENTRY_BLOCK_PTR_FOR_FN (cfun)
    4803                 :          0 :       || bb == EXIT_BLOCK_PTR_FOR_FN (cfun))
    4804                 :            :     return true;
    4805                 :            : 
    4806                 :          0 :   FOR_BB_INSNS (bb, insn)
    4807                 :          0 :     if (NONDEBUG_INSN_P (insn) && !any_uncondjump_p (insn))
    4808                 :            :       return false;
    4809                 :            : 
    4810                 :            :   return true;
    4811                 :            : }
    4812                 :            : 
    4813                 :            : /* Split a basic block if it ends with a conditional branch and if
    4814                 :            :    the other part of the block is not empty.  */
    4815                 :            : 
    4816                 :            : static basic_block
    4817                 :          0 : rtl_split_block_before_cond_jump (basic_block bb)
    4818                 :            : {
    4819                 :          0 :   rtx_insn *insn;
    4820                 :          0 :   rtx_insn *split_point = NULL;
    4821                 :          0 :   rtx_insn *last = NULL;
    4822                 :          0 :   bool found_code = false;
    4823                 :            : 
    4824                 :          0 :   FOR_BB_INSNS (bb, insn)
    4825                 :            :     {
    4826                 :          0 :       if (any_condjump_p (insn))
    4827                 :            :         split_point = last;
    4828                 :          0 :       else if (NONDEBUG_INSN_P (insn))
    4829                 :          0 :         found_code = true;
    4830                 :          0 :       last = insn;
    4831                 :            :     }
    4832                 :            : 
    4833                 :            :   /* Did not find everything.  */ 
    4834                 :          0 :   if (found_code && split_point)
    4835                 :          0 :     return split_block (bb, split_point)->dest;
    4836                 :            :   else 
    4837                 :            :     return NULL;
    4838                 :            : }
    4839                 :            : 
    4840                 :            : /* Return 1 if BB ends with a call, possibly followed by some
    4841                 :            :    instructions that must stay with the call, 0 otherwise.  */
    4842                 :            : 
    4843                 :            : static bool
    4844                 :    6226710 : rtl_block_ends_with_call_p (basic_block bb)
    4845                 :            : {
    4846                 :    6226710 :   rtx_insn *insn = BB_END (bb);
    4847                 :            : 
    4848                 :    7565200 :   while (!CALL_P (insn)
    4849                 :    6587930 :          && insn != BB_HEAD (bb)
    4850                 :   14132800 :          && (keep_with_call_p (insn)
    4851                 :    6567430 :              || NOTE_P (insn)
    4852                 :    6482400 :              || DEBUG_INSN_P (insn)))
    4853                 :    1338500 :     insn = PREV_INSN (insn);
    4854                 :    6226710 :   return (CALL_P (insn));
    4855                 :            : }
    4856                 :            : 
    4857                 :            : /* Return 1 if BB ends with a conditional branch, 0 otherwise.  */
    4858                 :            : 
    4859                 :            : static bool
    4860                 :          0 : rtl_block_ends_with_condjump_p (const_basic_block bb)
    4861                 :            : {
    4862                 :          0 :   return any_condjump_p (BB_END (bb));
    4863                 :            : }
    4864                 :            : 
    4865                 :            : /* Return true if we need to add fake edge to exit.
    4866                 :            :    Helper function for rtl_flow_call_edges_add.  */
    4867                 :            : 
    4868                 :            : static bool
    4869                 :          0 : need_fake_edge_p (const rtx_insn *insn)
    4870                 :            : {
    4871                 :          0 :   if (!INSN_P (insn))
    4872                 :            :     return false;
    4873                 :            : 
    4874                 :          0 :   if ((CALL_P (insn)
    4875                 :          0 :        && !SIBLING_CALL_P (insn)
    4876                 :          0 :        && !find_reg_note (insn, REG_NORETURN, NULL)
    4877                 :          0 :        && !(RTL_CONST_OR_PURE_CALL_P (insn))))
    4878                 :            :     return true;
    4879                 :            : 
    4880                 :          0 :   return ((GET_CODE (PATTERN (insn)) == ASM_OPERANDS
    4881                 :          0 :            && MEM_VOLATILE_P (PATTERN (insn)))
    4882                 :          0 :           || (GET_CODE (PATTERN (insn)) == PARALLEL
    4883                 :          0 :               && asm_noperands (insn) != -1
    4884                 :          0 :               && MEM_VOLATILE_P (XVECEXP (PATTERN (insn), 0, 0)))
    4885                 :          0 :           || GET_CODE (PATTERN (insn)) == ASM_INPUT);
    4886                 :            : }
    4887                 :            : 
    4888                 :            : /* Add fake edges to the function exit for any non constant and non noreturn
    4889                 :            :    calls, volatile inline assembly in the bitmap of blocks specified by
    4890                 :            :    BLOCKS or to the whole CFG if BLOCKS is zero.  Return the number of blocks
    4891                 :            :    that were split.
    4892                 :            : 
    4893                 :            :    The goal is to expose cases in which entering a basic block does not imply
    4894                 :            :    that all subsequent instructions must be executed.  */
    4895                 :            : 
    4896                 :            : static int
    4897                 :          0 : rtl_flow_call_edges_add (sbitmap blocks)
    4898                 :            : {
    4899                 :          0 :   int i;
    4900                 :          0 :   int blocks_split = 0;
    4901                 :          0 :   int last_bb = last_basic_block_for_fn (cfun);
    4902                 :          0 :   bool check_last_block = false;
    4903                 :            : 
    4904                 :          0 :   if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS)
    4905                 :            :     return 0;
    4906                 :            : 
    4907                 :          0 :   if (! blocks)
    4908                 :            :     check_last_block = true;
    4909                 :            :   else
    4910                 :          0 :     check_last_block = bitmap_bit_p (blocks,
    4911                 :          0 :                                      EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb->index);
    4912                 :            : 
    4913                 :            :   /* In the last basic block, before epilogue generation, there will be
    4914                 :            :      a fallthru edge to EXIT.  Special care is required if the last insn
    4915                 :            :      of the last basic block is a call because make_edge folds duplicate
    4916                 :            :      edges, which would result in the fallthru edge also being marked
    4917                 :            :      fake, which would result in the fallthru edge being removed by
    4918                 :            :      remove_fake_edges, which would result in an invalid CFG.
    4919                 :            : 
    4920                 :            :      Moreover, we can't elide the outgoing fake edge, since the block
    4921                 :            :      profiler needs to take this into account in order to solve the minimal
    4922                 :            :      spanning tree in the case that the call doesn't return.
    4923                 :            : 
    4924                 :            :      Handle this by adding a dummy instruction in a new last basic block.  */
    4925                 :          0 :   if (check_last_block)
    4926                 :            :     {
    4927                 :          0 :       basic_block bb = EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb;
    4928                 :          0 :       rtx_insn *insn = BB_END (bb);
    4929                 :            : 
    4930                 :            :       /* Back up past insns that must be kept in the same block as a call.  */
    4931                 :          0 :       while (insn != BB_HEAD (bb)
    4932                 :          0 :              && keep_with_call_p (insn))
    4933                 :          0 :         insn = PREV_INSN (insn);
    4934                 :            : 
    4935                 :          0 :       if (need_fake_edge_p (insn))
    4936                 :            :         {
    4937                 :          0 :           edge e;
    4938                 :            : 
    4939                 :          0 :           e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun));
    4940                 :          0 :           if (e)
    4941                 :            :             {
    4942                 :          0 :               insert_insn_on_edge (gen_use (const0_rtx), e);
    4943                 :          0 :               commit_edge_insertions ();
    4944                 :            :             }
    4945                 :            :         }
    4946                 :            :     }
    4947                 :            : 
    4948                 :            :   /* Now add fake edges to the function exit for any non constant
    4949                 :            :      calls since there is no way that we can determine if they will
    4950                 :            :      return or not...  */
    4951                 :            : 
    4952                 :          0 :   for (i = NUM_FIXED_BLOCKS; i < last_bb; i++)
    4953                 :            :     {
    4954                 :          0 :       basic_block bb = BASIC_BLOCK_FOR_FN (cfun, i);
    4955                 :          0 :       rtx_insn *insn;
    4956                 :          0 :       rtx_insn *prev_insn;
    4957                 :            : 
    4958                 :          0 :       if (!bb)
    4959                 :          0 :         continue;
    4960                 :            : 
    4961                 :          0 :       if (blocks && !bitmap_bit_p (blocks, i))
    4962                 :          0 :         continue;
    4963                 :            : 
    4964                 :          0 :       for (insn = BB_END (bb); ; insn = prev_insn)
    4965                 :            :         {
    4966                 :          0 :           prev_insn = PREV_INSN (insn);
    4967                 :          0 :           if (need_fake_edge_p (insn))
    4968                 :            :             {
    4969                 :          0 :               edge e;
    4970                 :          0 :               rtx_insn *split_at_insn = insn;
    4971                 :            : 
    4972                 :            :               /* Don't split the block between a call and an insn that should
    4973                 :            :                  remain in the same block as the call.  */
    4974                 :          0 :               if (CALL_P (insn))
    4975                 :          0 :                 while (split_at_insn != BB_END (bb)
    4976                 :          0 :                        && keep_with_call_p (NEXT_INSN (split_at_insn)))
    4977                 :          0 :                   split_at_insn = NEXT_INSN (split_at_insn);
    4978                 :            : 
    4979                 :            :               /* The handling above of the final block before the epilogue
    4980                 :            :                  should be enough to verify that there is no edge to the exit
    4981                 :            :                  block in CFG already.  Calling make_edge in such case would
    4982                 :            :                  cause us to mark that edge as fake and remove it later.  */
    4983                 :            : 
    4984                 :          0 :               if (flag_checking && split_at_insn == BB_END (bb))
    4985                 :            :                 {
    4986                 :          0 :                   e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun));
    4987                 :          0 :                   gcc_assert (e == NULL);
    4988                 :            :                 }
    4989                 :            : 
    4990                 :            :               /* Note that the following may create a new basic block
    4991                 :            :                  and renumber the existing basic blocks.  */
    4992                 :          0 :               if (split_at_insn != BB_END (bb))
    4993                 :            :                 {
    4994                 :          0 :                   e = split_block (bb, split_at_insn);
    4995                 :          0 :                   if (e)
    4996                 :          0 :                     blocks_split++;
    4997                 :            :                 }
    4998                 :            : 
    4999                 :          0 :               edge ne = make_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), EDGE_FAKE);
    5000                 :          0 :               ne->probability = profile_probability::guessed_never ();
    5001                 :            :             }
    5002                 :            : 
    5003                 :          0 :           if (insn == BB_HEAD (bb))
    5004                 :            :             break;
    5005                 :            :         }
    5006                 :            :     }
    5007                 :            : 
    5008                 :          0 :   if (blocks_split)
    5009                 :          0 :     verify_flow_info ();
    5010                 :            : 
    5011                 :            :   return blocks_split;
    5012                 :            : }
    5013                 :            : 
    5014                 :            : /* Add COMP_RTX as a condition at end of COND_BB.  FIRST_HEAD is
    5015                 :            :    the conditional branch target, SECOND_HEAD should be the fall-thru
    5016                 :            :    there is no need to handle this here the loop versioning code handles
    5017                 :            :    this.  the reason for SECON_HEAD is that it is needed for condition
    5018                 :            :    in trees, and this should be of the same type since it is a hook.  */
    5019                 :            : static void
    5020                 :          0 : rtl_lv_add_condition_to_bb (basic_block first_head ,
    5021                 :            :                             basic_block second_head ATTRIBUTE_UNUSED,
    5022                 :            :                             basic_block cond_bb, void *comp_rtx)
    5023                 :            : {
    5024                 :          0 :   rtx_code_label *label;
    5025                 :          0 :   rtx_insn *seq, *jump;
    5026                 :          0 :   rtx op0 = XEXP ((rtx)comp_rtx, 0);
    5027                 :          0 :   rtx op1 = XEXP ((rtx)comp_rtx, 1);
    5028                 :          0 :   enum rtx_code comp = GET_CODE ((rtx)comp_rtx);
    5029                 :          0 :   machine_mode mode;
    5030                 :            : 
    5031                 :            : 
    5032                 :          0 :   label = block_label (first_head);
    5033                 :          0 :   mode = GET_MODE (op0);
    5034                 :          0 :   if (mode == VOIDmode)
    5035                 :          0 :     mode = GET_MODE (op1);
    5036                 :            : 
    5037                 :          0 :   start_sequence ();
    5038                 :          0 :   op0 = force_operand (op0, NULL_RTX);
    5039                 :          0 :   op1 = force_operand (op1, NULL_RTX);
    5040                 :          0 :   do_compare_rtx_and_jump (op0, op1, comp, 0, mode, NULL_RTX, NULL, label,
    5041                 :            :                            profile_probability::uninitialized ());
    5042                 :          0 :   jump = get_last_insn ();
    5043                 :          0 :   JUMP_LABEL (jump) = label;
    5044                 :          0 :   LABEL_NUSES (label)++;
    5045                 :          0 :   seq = get_insns ();
    5046                 :          0 :   end_sequence ();
    5047                 :            : 
    5048                 :            :   /* Add the new cond, in the new head.  */
    5049                 :          0 :   emit_insn_after (seq, BB_END (cond_bb));
    5050                 :          0 : }
    5051                 :            : 
    5052                 :            : 
    5053                 :            : /* Given a block B with unconditional branch at its end, get the
    5054                 :            :    store the return the branch edge and the fall-thru edge in
    5055                 :            :    BRANCH_EDGE and FALLTHRU_EDGE respectively.  */
    5056                 :            : static void
    5057                 :          0 : rtl_extract_cond_bb_edges (basic_block b, edge *branch_edge,
    5058                 :            :                            edge *fallthru_edge)
    5059                 :            : {
    5060                 :          0 :   edge e = EDGE_SUCC (b, 0);
    5061                 :            : 
    5062                 :          0 :   if (e->flags & EDGE_FALLTHRU)
    5063                 :            :     {
    5064                 :          0 :       *fallthru_edge = e;
    5065                 :          0 :       *branch_edge = EDGE_SUCC (b, 1);
    5066                 :            :     }
    5067                 :            :   else
    5068                 :            :     {
    5069                 :          0 :       *branch_edge = e;
    5070                 :          0 :       *fallthru_edge = EDGE_SUCC (b, 1);
    5071                 :            :     }
    5072                 :          0 : }
    5073                 :            : 
    5074                 :            : void
    5075                 :   17687200 : init_rtl_bb_info (basic_block bb)
    5076                 :            : {
    5077                 :   17687200 :   gcc_assert (!bb->il.x.rtl);
    5078                 :   17687200 :   bb->il.x.head_ = NULL;
    5079                 :   17687200 :   bb->il.x.rtl = ggc_cleared_alloc<rtl_bb_info> ();
    5080                 :   17687200 : }
    5081                 :            : 
    5082                 :            : /* Returns true if it is possible to remove edge E by redirecting
    5083                 :            :    it to the destination of the other edge from E->src.  */
    5084                 :            : 
    5085                 :            : static bool
    5086                 :      67375 : rtl_can_remove_branch_p (const_edge e)
    5087                 :            : {
    5088                 :      67375 :   const_basic_block src = e->src;
    5089                 :      67375 :   const_basic_block target = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest;
    5090                 :      67375 :   const rtx_insn *insn = BB_END (src);
    5091                 :      67375 :   rtx set;
    5092                 :            : 
    5093                 :            :   /* The conditions are taken from try_redirect_by_replacing_jump.  */
    5094                 :      67375 :   if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
    5095                 :            :     return false;
    5096                 :            : 
    5097                 :      67375 :   if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
    5098                 :            :     return false;
    5099                 :            : 
    5100                 :      67375 :   if (BB_PARTITION (src) != BB_PARTITION (target))
    5101                 :            :     return false;
    5102                 :            : 
    5103                 :      67375 :   if (!onlyjump_p (insn)
    5104                 :      67375 :       || tablejump_p (insn, NULL, NULL))
    5105                 :          0 :     return false;
    5106                 :            : 
    5107                 :      67375 :   set = single_set (insn);
    5108                 :      67375 :   if (!set || side_effects_p (set))
    5109                 :          0 :     return false;
    5110                 :            : 
    5111                 :            :   return true;
    5112                 :            : }
    5113                 :            : 
    5114                 :            : static basic_block
    5115                 :      20611 : rtl_duplicate_bb (basic_block bb, copy_bb_data *id)
    5116                 :            : {
    5117                 :      20611 :   bb = cfg_layout_duplicate_bb (bb, id);
    5118                 :      20611 :   bb->aux = NULL;
    5119                 :      20611 :   return bb;
    5120                 :            : }
    5121                 :            : 
    5122                 :            : /* Do book-keeping of basic block BB for the profile consistency checker.
    5123                 :            :    Store the counting in RECORD.  */
    5124                 :            : static void
    5125                 :          0 : rtl_account_profile_record (basic_block bb, struct profile_record *record)
    5126                 :            : {
    5127                 :          0 :   rtx_insn *insn;
    5128                 :          0 :   FOR_BB_INSNS (bb, insn)
    5129                 :          0 :     if (INSN_P (insn))
    5130                 :            :       {
    5131                 :          0 :         record->size += insn_cost (insn, false);
    5132                 :          0 :         if (bb->count.initialized_p ())
    5133                 :          0 :           record->time
    5134                 :          0 :             += insn_cost (insn, true) * bb->count.to_gcov_type ();
    5135                 :          0 :         else if (profile_status_for_fn (cfun) == PROFILE_GUESSED)
    5136                 :          0 :           record->time
    5137                 :          0 :             += insn_cost (insn, true) * bb->count.to_frequency (cfun);
    5138                 :            :       }
    5139                 :          0 : }
    5140                 :            : 
    5141                 :            : /* Implementation of CFG manipulation for linearized RTL.  */
    5142                 :            : struct cfg_hooks rtl_cfg_hooks = {
    5143                 :            :   "rtl",
    5144                 :            :   rtl_verify_flow_info,
    5145                 :            :   rtl_dump_bb,
    5146                 :            :   rtl_dump_bb_for_graph,
    5147                 :            :   rtl_create_basic_block,
    5148                 :            :   rtl_redirect_edge_and_branch,
    5149                 :            :   rtl_redirect_edge_and_branch_force,
    5150                 :            :   rtl_can_remove_branch_p,
    5151                 :            :   rtl_delete_block,
    5152                 :            :   rtl_split_block,
    5153                 :            :   rtl_move_block_after,
    5154                 :            :   rtl_can_merge_blocks,  /* can_merge_blocks_p */
    5155                 :            :   rtl_merge_blocks,
    5156                 :            :   rtl_predict_edge,
    5157                 :            :   rtl_predicted_by_p,
    5158                 :            :   cfg_layout_can_duplicate_bb_p,
    5159                 :            :   rtl_duplicate_bb,
    5160                 :            :   rtl_split_edge,
    5161                 :            :   rtl_make_forwarder_block,
    5162                 :            :   rtl_tidy_fallthru_edge,
    5163                 :            :   rtl_force_nonfallthru,
    5164                 :            :   rtl_block_ends_with_call_p,
    5165                 :            :   rtl_block_ends_with_condjump_p,
    5166                 :            :   rtl_flow_call_edges_add,
    5167                 :            :   NULL, /* execute_on_growing_pred */
    5168                 :            :   NULL, /* execute_on_shrinking_pred */
    5169                 :            :   NULL, /* duplicate loop for trees */
    5170                 :            :   NULL, /* lv_add_condition_to_bb */
    5171                 :            :   NULL, /* lv_adjust_loop_header_phi*/
    5172                 :            :   NULL, /* extract_cond_bb_edges */
    5173                 :            :   NULL, /* flush_pending_stmts */
    5174                 :            :   rtl_block_empty_p, /* block_empty_p */
    5175                 :            :   rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */
    5176                 :            :   rtl_account_profile_record,
    5177                 :            : };
    5178                 :            : 
    5179                 :            : /* Implementation of CFG manipulation for cfg layout RTL, where
    5180                 :            :    basic block connected via fallthru edges does not have to be adjacent.
    5181                 :            :    This representation will hopefully become the default one in future
    5182                 :            :    version of the compiler.  */
    5183                 :            : 
    5184                 :            : struct cfg_hooks cfg_layout_rtl_cfg_hooks = {
    5185                 :            :   "cfglayout mode",
    5186                 :            :   rtl_verify_flow_info_1,
    5187                 :            :   rtl_dump_bb,
    5188                 :            :   rtl_dump_bb_for_graph,
    5189                 :            :   cfg_layout_create_basic_block,
    5190                 :            :   cfg_layout_redirect_edge_and_branch,
    5191                 :            :   cfg_layout_redirect_edge_and_branch_force,
    5192                 :            :   rtl_can_remove_branch_p,
    5193                 :            :   cfg_layout_delete_block,
    5194                 :            :   cfg_layout_split_block,
    5195                 :            :   rtl_move_block_after,
    5196                 :            :   cfg_layout_can_merge_blocks_p,
    5197                 :            :   cfg_layout_merge_blocks,
    5198                 :            :   rtl_predict_edge,
    5199                 :            :   rtl_predicted_by_p,
    5200                 :            :   cfg_layout_can_duplicate_bb_p,
    5201                 :            :   cfg_layout_duplicate_bb,
    5202                 :            :   cfg_layout_split_edge,
    5203                 :            :   rtl_make_forwarder_block,
    5204                 :            :   NULL, /* tidy_fallthru_edge */
    5205                 :            :   rtl_force_nonfallthru,
    5206                 :            :   rtl_block_ends_with_call_p,
    5207                 :            :   rtl_block_ends_with_condjump_p,
    5208                 :            :   rtl_flow_call_edges_add,
    5209                 :            :   NULL, /* execute_on_growing_pred */
    5210                 :            :   NULL, /* execute_on_shrinking_pred */
    5211                 :            :   duplicate_loop_to_header_edge, /* duplicate loop for trees */
    5212                 :            :   rtl_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
    5213                 :            :   NULL, /* lv_adjust_loop_header_phi*/
    5214                 :            :   rtl_extract_cond_bb_edges, /* extract_cond_bb_edges */
    5215                 :            :   NULL, /* flush_pending_stmts */  
    5216                 :            :   rtl_block_empty_p, /* block_empty_p */
    5217                 :            :   rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */
    5218                 :            :   rtl_account_profile_record,
    5219                 :            : };
    5220                 :            : 
    5221                 :            : #include "gt-cfgrtl.h"
    5222                 :            : 
    5223                 :            : #if __GNUC__ >= 10
    5224                 :            : #  pragma GCC diagnostic pop
    5225                 :            : #endif

Generated by: LCOV version 1.0

LCOV profile is generated on x86_64 machine using following configure options: configure --disable-bootstrap --enable-coverage=opt --enable-languages=c,c++,fortran,go,jit,lto --enable-host-shared. GCC test suite is run with the built compiler.