1 // RTL SSA classes related to changing instructions -*- C++ -*- 2 // Copyright (C) 2020-2022 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 // A class that describes a change that we're considering making to an 23 // instruction. There are three choices: 24 // 25 // (1) delete the instruction 26 // (2) replace the instruction with a new instruction in-place 27 // (3) replace the instruction with a new instruction at a different location 28 // 29 // Anything related to the "new instruction" is irrelevant for (1). 30 // 31 // The class doesn't actually change anything itself, it simply records 32 // something that we might do. 33 class insn_change 34 { 35 public: 36 enum delete_action { DELETE }; 37 38 // Construct a possible change to INSN. 39 insn_change (insn_info *insn); 40 41 // Construct a possible deletion of INSN. 42 insn_change (insn_info *insn, delete_action); 43 44 // The instruction that we would change. insn()45 insn_info *insn () const { return m_insn; } 46 47 // The rtx_insn of the instruction that we would change. rtl()48 rtx_insn *rtl () const { return m_insn->rtl (); } 49 50 // The basic block that contains insn (). bb()51 bb_info *bb () const { return m_insn->bb (); } 52 53 // The extended basic block that contains insn (). ebb()54 ebb_info *ebb () const { return m_insn->ebb (); } 55 56 // The uid of the instruction that we would change. insn_uid()57 unsigned int insn_uid () const { return m_insn->uid (); } 58 59 // The list of things that the original instruction defined and used. old_defs()60 def_array old_defs () const { return m_insn->defs (); } old_uses()61 use_array old_uses () const { return m_insn->uses (); } 62 63 // The cost of the original instruction, as calculated by the target. old_cost()64 unsigned int old_cost () const { return m_insn->cost (); } 65 66 // Return true if the original instruction would simply be deleted, 67 // rather than being replaced by a new instruction. is_deletion()68 bool is_deletion () const { return m_is_deletion; } 69 70 // Print a description of the change to PP. 71 void print (pretty_printer *pp) const; 72 73 // Return an insn_change for deleting INSN. delete_insn(insn_info * insn)74 static insn_change delete_insn (insn_info *insn) { return { insn, DELETE }; } 75 76 private: 77 // The value returned by insn (). 78 insn_info *m_insn; 79 80 public: 81 // The list of things that the new instruction would define and use. 82 def_array new_defs; 83 use_array new_uses; 84 85 // The range of instructions after which the instruction could be placed. 86 // The range can include INSN itself: placing the instruction after either 87 // INSN or INSN->prev_nondebug_insn () is equivalent to not moving the 88 // instruction. 89 insn_range_info move_range; 90 91 // The cost that the new instruction would have, as calculated by the target. 92 unsigned int new_cost; 93 94 private: 95 // The value returned by is_deletion (). 96 bool m_is_deletion; 97 }; 98 99 // A class that represents a closure of the two-argument form of 100 // insn_is_changing. See the comment above the one-argument form 101 // for details. 102 class insn_is_changing_closure 103 { 104 public: 105 insn_is_changing_closure (array_slice<insn_change *const> changes); 106 bool operator() (const insn_info *) const; 107 108 private: 109 array_slice<insn_change *const> m_changes; 110 }; 111 112 void pp_insn_change (pretty_printer *, const insn_change &); 113 114 } 115 116 void dump (FILE *, const rtl_ssa::insn_change &); 117 118 void DEBUG_FUNCTION debug (const rtl_ssa::insn_change &); 119