gcc/insn-notes.def

   1 /* Insn note definitions.
   2    Copyright (C) 2004 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 2, 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 COPYING.  If not, write to the Free
  18 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  19 02111-1307, USA.  */
  20
  21 /* This file defines all the codes that may appear in the
  22    NOTE_LINE_NUMBER field of a NOTE insn for kinds of notes that are
  23    not line numbers.  Source files define DEF_INSN_NOTE appropriately
  24    before including this file.
  25
  26    We are slowly removing the concept of insn-chain notes from the
  27    compiler.  Adding new codes to this file is STRONGLY DISCOURAGED.
  28    If you think you need one, look for other ways to express what you
  29    mean, such as register notes or bits in the basic-block structure.  */
  30
  31 /* Shorthand.  */
  32 #define INSN_NOTE(NAME) DEF_INSN_NOTE (NOTE_INSN_##NAME)
  33
  34 /* This note is used to get rid of an insn when it isn't safe to patch
  35    the insn out of the chain.  */
  36 INSN_NOTE (DELETED)
  37
  38 /* Generated in place of user-declared labels when they are deleted.  */
  39 INSN_NOTE (DELETED_LABEL)
  40
  41 /* These are used to mark the beginning and end of a lexical block.
  42    See NOTE_BLOCK and reorder_blocks.  */
  43 INSN_NOTE (BLOCK_BEG)
  44 INSN_NOTE (BLOCK_END)
  45
  46 /* These mark the extremes of a loop.  */
  47 INSN_NOTE (LOOP_BEG)
  48 INSN_NOTE (LOOP_END)
  49
  50 /* This note indicates the start of the real body of the function,
  51    i.e. the point just after all of the parms have been moved into
  52    their homes, etc.  */
  53 INSN_NOTE (FUNCTION_BEG)
  54
  55 /* This kind of note is generated at the end of the function body,
  56    just before the return insn or return label.  In an optimizing
  57    compilation it is deleted by the first jump optimization, after
  58    enabling that optimizer to determine whether control can fall
  59    off the end of the function body without a return statement.  */
  60 INSN_NOTE (FUNCTION_END)
  61
  62 /* This marks the point immediately after the last prologue insn.  */
  63 INSN_NOTE (PROLOGUE_END)
  64
  65 /* This marks the point immediately prior to the first epilogue insn.  */
  66 INSN_NOTE (EPILOGUE_BEG)
  67
  68 /* These note where exception handling regions begin and end.
  69    Uses NOTE_EH_HANDLER to identify the region in question.  */
  70 INSN_NOTE (EH_REGION_BEG)
  71 INSN_NOTE (EH_REGION_END)
  72
  73 /* Generated whenever a duplicate line number note is output.
  74    For example, one is output after the end of an inline function,
  75    in order to prevent the line containing the inline call from
  76    being counted twice in gcov.  */
  77 INSN_NOTE (REPEATED_LINE_NUMBER)
  78
  79 /* The location of a variable.  */
  80 INSN_NOTE (VAR_LOCATION)
  81
  82 /* Record the expected value of a register at a location.  Uses
  83    NOTE_EXPECTED_VALUE; stored as (eq (reg) (const_int)).  */
  84 INSN_NOTE (EXPECTED_VALUE)
  85
  86 /* Record the struct for the following basic block.  Uses
  87    NOTE_BASIC_BLOCK.  FIXME: Redundant with the basic block pointer
  88    now included in every insn.  */
  89 INSN_NOTE (BASIC_BLOCK)
  90
  91 /* Record that the current basic block is unlikely to be executed and
  92    should be moved to the UNLIKELY_EXECUTED_TEXT_SECTION.  FIXME: Make
  93    this a bit on the basic block structure.  */
  94 INSN_NOTE (UNLIKELY_EXECUTED_CODE)
  95
  96 #undef INSN_NOTE