gcc/valtrack.h

   1 /* Infrastructure for tracking user variable locations and values
   2    throughout compilation.
   3    Copyright (C) 2010-2015 Free Software Foundation, Inc.
   4    Contributed by Alexandre Oliva <aoliva@redhat.com>.
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #ifndef GCC_VALTRACK_H
  23 #define GCC_VALTRACK_H
  24
  25 #include "bitmap.h"
  26 #include "df.h"
  27 #include "rtl.h"
  28
  29 /* Debug uses of dead regs.  */
  30
  31 /* Entry that maps a dead pseudo (REG) used in a debug insns that dies
  32    at different blocks to the debug temp (DTEMP) it was replaced
  33    with.  */
  34
  35 struct dead_debug_global_entry
  36 {
  37   rtx reg;
  38   rtx dtemp;
  39 };
  40
  41 /* Descriptor for hash_table to hash by dead_debug_global_entry's REG
  42    and map to DTEMP.  */
  43
  44 struct dead_debug_hash_descr : free_ptr_hash <dead_debug_global_entry>
  45 {
  46   /* Hash on the pseudo number.  */
  47   static inline hashval_t hash (const dead_debug_global_entry *my);
  48   /* Entries are identical if they refer to the same pseudo.  */
  49   static inline bool equal (const dead_debug_global_entry *my,
  50                             const dead_debug_global_entry *other);
  51 };
  52
  53 /* Hash on the pseudo number.  */
  54 inline hashval_t
  55 dead_debug_hash_descr::hash (const dead_debug_global_entry *my)
  56 {
  57   return REGNO (my->reg);
  58 }
  59
  60 /* Entries are identical if they refer to the same pseudo.  */
  61 inline bool
  62 dead_debug_hash_descr::equal (const dead_debug_global_entry *my,
  63                               const dead_debug_global_entry *other)
  64 {
  65   return my->reg == other->reg;
  66 }
  67
  68 /* Maintain a global table of pseudos used in debug insns after their
  69    deaths in other blocks, and debug temps their deathpoint values are
  70    to be bound to.  */
  71
  72 struct dead_debug_global
  73 {
  74   /* This hash table that maps pseudos to debug temps.  */
  75   hash_table<dead_debug_hash_descr> *htab;
  76   /* For each entry in htab, the bit corresponding to its REGNO will
  77      be set.  */
  78   bitmap used;
  79 };
  80
  81 /* Node of a linked list of uses of dead REGs in debug insns.  */
  82
  83 struct dead_debug_use
  84 {
  85   df_ref use;
  86   struct dead_debug_use *next;
  87 };
  88
  89 /* Linked list of the above, with a bitmap of the REGs in the
  90    list.  */
  91
  92 struct dead_debug_local
  93 {
  94   /* The first dead_debug_use entry in the list.  */
  95   struct dead_debug_use *head;
  96   /* A pointer to the global tracking data structure.  */
  97   struct dead_debug_global *global;
  98   /* A bitmap that has bits set for each REG used in the
  99      dead_debug_use list, and for each entry in the global hash
 100      table.  */
 101   bitmap used;
 102   /* A bitmap that has bits set for each INSN that is to be
 103      rescanned.  */
 104   bitmap to_rescan;
 105 };
 106
 107 /* This type controls the behavior of dead_debug_insert_temp WRT
 108    UREGNO and INSN.  */
 109
 110 enum debug_temp_where
 111   {
 112     /* Bind a newly-created debug temporary to a REG for UREGNO, and
 113        insert the debug insn before INSN.  REG is expected to die at
 114        INSN.  */
 115     DEBUG_TEMP_BEFORE_WITH_REG = -1,
 116     /* Bind a newly-created debug temporary to the value INSN stores
 117        in REG, and insert the debug insn before INSN.  */
 118     DEBUG_TEMP_BEFORE_WITH_VALUE = 0,
 119     /* Bind a newly-created debug temporary to a REG for UREGNO, and
 120        insert the debug insn after INSN.  REG is expected to be set at
 121        INSN.  */
 122     DEBUG_TEMP_AFTER_WITH_REG = 1,
 123     /* Like DEBUG_TEMP_AFTER_WITH_REG, but force addition of a debug
 124        temporary even if there is just a single debug use.  This is used
 125        on regs that are becoming REG_DEAD on INSN and so uses of the
 126        reg later on are invalid.  */
 127     DEBUG_TEMP_AFTER_WITH_REG_FORCE = 2
 128   };
 129
 130 extern void dead_debug_global_init (struct dead_debug_global *, bitmap);
 131 extern void dead_debug_global_finish (struct dead_debug_global *, bitmap);
 132 extern void dead_debug_local_init (struct dead_debug_local *, bitmap,
 133                                    struct dead_debug_global *);
 134 extern void dead_debug_local_finish (struct dead_debug_local *, bitmap);
 135 extern void dead_debug_add (struct dead_debug_local *, df_ref, unsigned int);
 136 extern int dead_debug_insert_temp (struct dead_debug_local *,
 137                                    unsigned int uregno, rtx_insn *insn,
 138                                    enum debug_temp_where);
 139
 140 extern void propagate_for_debug (rtx_insn *, rtx_insn *, rtx, rtx, basic_block);
 141
 142
 143 #endif /* GCC_VALTRACK_H */