gcc/print-rtl.h

   1 /* Print RTL for GCC.
   2    Copyright (C) 1987-2021 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 #ifndef GCC_PRINT_RTL_H
  21 #define GCC_PRINT_RTL_H
  22
  23 #ifndef GENERATOR_FILE
  24 #include "bitmap.h"
  25 #endif /* #ifndef GENERATOR_FILE */
  26
  27 class rtx_reuse_manager;
  28
  29 /* A class for writing rtx to a FILE *.  */
  30
  31 class rtx_writer
  32 {
  33  public:
  34   rtx_writer (FILE *outfile, int ind, bool simple, bool compact,
  35               rtx_reuse_manager *reuse_manager);
  36
  37   void print_rtx (const_rtx in_rtx);
  38   void print_rtl (const_rtx rtx_first);
  39   int print_rtl_single_with_indent (const_rtx x, int ind);
  40
  41   void finish_directive ();
  42
  43  private:
  44   void print_rtx_operand_code_0 (const_rtx in_rtx, int idx);
  45   void print_rtx_operand_code_e (const_rtx in_rtx, int idx);
  46   void print_rtx_operand_codes_E_and_V (const_rtx in_rtx, int idx);
  47   void print_rtx_operand_code_i (const_rtx in_rtx, int idx);
  48   void print_rtx_operand_code_r (const_rtx in_rtx);
  49   void print_rtx_operand_code_u (const_rtx in_rtx, int idx);
  50   void print_rtx_operand (const_rtx in_rtx, int idx);
  51   bool operand_has_default_value_p (const_rtx in_rtx, int idx);
  52
  53  private:
  54   FILE *m_outfile;
  55   int m_sawclose;
  56   int m_indent;
  57   bool m_in_call_function_usage;
  58
  59   /* True means use simplified format without flags, modes, etc.  */
  60   bool m_simple;
  61
  62   /* If true, use compact dump format:
  63      - PREV/NEXT_INSN UIDs are omitted
  64      - INSN_CODEs are omitted,
  65      - register numbers are omitted for hard and virtual regs, and
  66        non-virtual pseudos are offset relative to the first such reg, and
  67        printed with a '%' sigil e.g. "%0" for (LAST_VIRTUAL_REGISTER + 1),
  68      - insn names are prefixed with "c" (e.g. "cinsn", "cnote", etc).  */
  69   bool m_compact;
  70
  71   /* An optional instance of rtx_reuse_manager.  */
  72   rtx_reuse_manager *m_rtx_reuse_manager;
  73 };
  74
  75 #ifdef BUFSIZ
  76 extern void print_rtl (FILE *, const_rtx);
  77 #endif
  78 extern void print_rtx_insn_vec (FILE *file, const vec<rtx_insn *> &vec);
  79
  80 extern void dump_value_slim (FILE *, const_rtx, int);
  81 extern void dump_insn_slim (FILE *, const rtx_insn *);
  82 extern void dump_rtl_slim (FILE *, const rtx_insn *, const rtx_insn *,
  83                            int, int);
  84 extern void print_value (pretty_printer *, const_rtx, int);
  85 extern void print_pattern (pretty_printer *, const_rtx, int);
  86 extern void print_insn (pretty_printer *pp, const rtx_insn *x, int verbose);
  87 extern void print_insn_with_notes (pretty_printer *, const rtx_insn *);
  88
  89 extern void rtl_dump_bb_for_graph (pretty_printer *, basic_block);
  90 extern const char *str_pattern_slim (const_rtx);
  91
  92 extern void print_rtx_function (FILE *file, function *fn, bool compact);
  93
  94 #ifndef GENERATOR_FILE
  95
  96 /* For some rtx codes (such as SCRATCH), instances are defined to only be
  97    equal for pointer equality: two distinct SCRATCH instances are non-equal.
  98    copy_rtx preserves this equality by reusing the SCRATCH instance.
  99
 100    For example, in this x86 instruction:
 101
 102       (cinsn (set (mem/v:BLK (scratch:DI) [0  A8])
 103                     (unspec:BLK [
 104                             (mem/v:BLK (scratch:DI) [0  A8])
 105                         ] UNSPEC_MEMORY_BLOCKAGE)) "test.c":2
 106                  (nil))
 107
 108    the two instances of "(scratch:DI)" are actually the same underlying
 109    rtx pointer (and thus "equal"), and the insn will only be recognized
 110    (as "*memory_blockage") if this pointer-equality is preserved.
 111
 112    To be able to preserve this pointer-equality when round-tripping
 113    through dumping/loading the rtl, we need some syntax.  The first
 114    time a reused rtx is encountered in the dump, we prefix it with
 115    a reuse ID:
 116
 117       (0|scratch:DI)
 118
 119    Subsequent references to the rtx in the dump can be expressed using
 120    "reuse_rtx" e.g.:
 121
 122       (reuse_rtx 0)
 123
 124    This class is responsible for tracking a set of reuse IDs during a dump.
 125
 126    Dumping with reuse-support is done in two passes:
 127
 128    (a) a first pass in which "preprocess" is called on each top-level rtx
 129        to be seen in the dump.  This traverses the rtx and its descendents,
 130        identifying rtx that will be seen more than once in the actual dump,
 131        and assigning them reuse IDs.
 132
 133    (b) the actual dump, via print_rtx etc.  print_rtx detect the presence
 134        of a live rtx_reuse_manager and uses it if there is one.  Any rtx
 135        that were assigned reuse IDs will be printed with it the first time
 136        that they are seen, and then printed as "(reuse_rtx ID)" subsequently.
 137
 138    The first phase is needed since otherwise there would be no way to tell
 139    if an rtx will be reused when first encountering it.  */
 140
 141 class rtx_reuse_manager
 142 {
 143  public:
 144   rtx_reuse_manager ();
 145
 146   /* The first pass.  */
 147   void preprocess (const_rtx x);
 148
 149   /* The second pass (within print_rtx).  */
 150   bool has_reuse_id (const_rtx x, int *out);
 151   bool seen_def_p (int reuse_id);
 152   void set_seen_def (int reuse_id);
 153
 154  private:
 155   hash_map<const_rtx, int> m_rtx_occurrence_count;
 156   hash_map<const_rtx, int> m_rtx_reuse_ids;
 157   auto_bitmap m_defs_seen;
 158   int m_next_id;
 159 };
 160
 161 #endif /* #ifndef GENERATOR_FILE */
 162
 163 #endif  // GCC_PRINT_RTL_H