LCOV - code coverage report
Current view: top level - gcc/rtl-ssa - change-utils.h (source / functions) Coverage Total Hit
Test: gcc.info Lines: 100.0 % 12 12
Test Date: 2024-03-23 14:05:01 Functions: 100.0 % 3 3
Legend: Lines: hit not hit | Branches: + taken - not taken # not executed Branches: - 0 0

             Branch data     Line data    Source code
       1                 :             : // RTL SSA utility functions for changing instructions              -*- C++ -*-
       2                 :             : // Copyright (C) 2020-2024 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                 :             : namespace rtl_ssa {
      21                 :             : 
      22                 :             : // Return true if INSN is one of the instructions being changed by CHANGES.
      23                 :             : inline bool
      24                 :             : insn_is_changing (array_slice<insn_change *const> changes,
      25                 :             :                   const insn_info *insn)
      26                 :             : {
      27                 :             :   for (const insn_change *change : changes)
      28                 :             :     if (change->insn () == insn)
      29                 :             :       return true;
      30                 :             :   return false;
      31                 :             : }
      32                 :             : 
      33                 :             : // Return a closure of insn_is_changing, for use as a predicate.
      34                 :             : // This could be done using local lambdas instead, but the predicate is
      35                 :             : // used often enough that having a class should be more convenient and allow
      36                 :             : // reuse of template instantiations.
      37                 :             : //
      38                 :             : // We don't use std::bind because it would involve an indirect function call,
      39                 :             : // whereas this function is used in relatively performance-critical code.
      40                 :             : inline insn_is_changing_closure
      41                 :             : insn_is_changing (array_slice<insn_change *const> changes)
      42                 :             : {
      43                 :             :   return insn_is_changing_closure (changes);
      44                 :             : }
      45                 :             : 
      46                 :             : // Restrict CHANGE.move_range so that the changed instruction can perform
      47                 :             : // all its definitions and uses.  Assume that if:
      48                 :             : //
      49                 :             : // - CHANGE contains an access A1 of resource R;
      50                 :             : // - an instruction I2 contains another access A2 to R; and
      51                 :             : // - IGNORE (I2) is true
      52                 :             : //
      53                 :             : // then either:
      54                 :             : //
      55                 :             : // - A2 will be removed; or
      56                 :             : // - something will ensure that A1 and A2 maintain their current order,
      57                 :             : //   without this having to be enforced by CHANGE's move range.
      58                 :             : //
      59                 :             : // IGNORE should return true for CHANGE.insn ().
      60                 :             : //
      61                 :             : // Return true on success, otherwise leave CHANGE.move_range in an invalid
      62                 :             : // state.
      63                 :             : //
      64                 :             : // This function only works correctly for instructions that remain within
      65                 :             : // the same extended basic block.
      66                 :             : template<typename IgnorePredicate>
      67                 :             : bool
      68                 :    28221481 : restrict_movement_ignoring (insn_change &change, IgnorePredicate ignore)
      69                 :             : {
      70                 :             :   // Uses generally lead to failure quicker, so test those first.
      71                 :    28221481 :   return (restrict_movement_for_uses_ignoring (change.move_range,
      72                 :             :                                                change.new_uses, ignore)
      73                 :    26975150 :           && restrict_movement_for_defs_ignoring (change.move_range,
      74                 :             :                                                   change.new_defs, ignore)
      75                 :    55196631 :           && canonicalize_move_range (change.move_range, change.insn ()));
      76                 :             : }
      77                 :             : 
      78                 :             : // Like restrict_movement_ignoring, but ignore only the instruction
      79                 :             : // that is being changed.
      80                 :             : inline bool
      81                 :    28221481 : restrict_movement (insn_change &change)
      82                 :             : {
      83                 :    28221481 :   return restrict_movement_ignoring (change, insn_is (change.insn ()));
      84                 :             : }
      85                 :             : 
      86                 :             : using add_regno_clobber_fn = std::function<bool (insn_change &,
      87                 :             :                                                  unsigned int)>;
      88                 :             : bool recog_internal (insn_change &, add_regno_clobber_fn);
      89                 :             : 
      90                 :             : // Try to recognize the new instruction pattern for CHANGE, potentially
      91                 :             : // tweaking the pattern or adding extra clobbers in order to make it match.
      92                 :             : //
      93                 :             : // When adding an extra clobber for register R, restrict CHANGE.move_range
      94                 :             : // to a range of instructions for which R is not live.  When determining
      95                 :             : // whether R is live, ignore accesses made by an instruction I if
      96                 :             : // IGNORE (I) is true.  The caller then assumes the responsibility
      97                 :             : // of ensuring that CHANGE and I are placed in a valid order.
      98                 :             : //
      99                 :             : // IGNORE should return true for CHANGE.insn ().
     100                 :             : //
     101                 :             : // Return true on success.  Leave CHANGE unmodified on failure.
     102                 :             : template<typename IgnorePredicate>
     103                 :             : inline bool
     104                 :    15064319 : recog_ignoring (obstack_watermark &watermark, insn_change &change,
     105                 :             :                 IgnorePredicate ignore)
     106                 :             : {
     107                 :    15064319 :   auto add_regno_clobber = [&](insn_change &change, unsigned int regno)
     108                 :             :     {
     109                 :     1600361 :       return crtl->ssa->add_regno_clobber (watermark, change, regno, ignore);
     110                 :             :     };
     111                 :    15064319 :   return recog_internal (change, add_regno_clobber);
     112                 :             : }
     113                 :             : 
     114                 :             : // As for recog_ignoring, but ignore only the instruction that is being
     115                 :             : // changed.
     116                 :             : inline bool
     117                 :    15064319 : recog (obstack_watermark &watermark, insn_change &change)
     118                 :             : {
     119                 :    15064319 :   return recog_ignoring (watermark, change, insn_is (change.insn ()));
     120                 :             : }
     121                 :             : 
     122                 :             : // Check whether insn costs indicate that the net effect of the changes
     123                 :             : // in CHANGES is worthwhile.  Require a strict improvement if STRICT_P,
     124                 :             : // otherwise allow the new instructions to be the same cost as the old
     125                 :             : // instructions.
     126                 :             : bool changes_are_worthwhile (array_slice<insn_change *const> changes,
     127                 :             :                              bool strict_p = false);
     128                 :             : 
     129                 :             : // Like changes_are_worthwhile, but for a single change.
     130                 :             : inline bool
     131                 :             : change_is_worthwhile (insn_change &change, bool strict_p = false)
     132                 :             : {
     133                 :             :   insn_change *changes[] = { &change };
     134                 :             :   return changes_are_worthwhile (changes, strict_p);
     135                 :             : }
     136                 :             : 
     137                 :             : }
        

Generated by: LCOV version 2.0-1

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,rust,m2 --enable-host-shared. GCC test suite is run with the built compiler.