gcc/valtrack.h

   1 /* Infrastructure for tracking user variable locations and values
   2    throughout compilation.
   3    Copyright (C) 2010-2014 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 #include "basic-block.h"
  29 #include "hash-table.h"
  30
  31 /* Debug uses of dead regs.  */
  32
  33 /* Entry that maps a dead pseudo (REG) used in a debug insns that dies
  34    at different blocks to the debug temp (DTEMP) it was replaced
  35    with.  */
  36
  37 struct dead_debug_global_entry
  38 {
  39   rtx reg;
  40   rtx dtemp;
  41 };
  42
  43 /* Descriptor for hash_table to hash by dead_debug_global_entry's REG
  44    and map to DTEMP.  */
  45
  46 struct dead_debug_hash_descr
  47 {
  48   /* The hash table contains pointers to entries of this type.  */
  49   typedef struct dead_debug_global_entry value_type;
  50   typedef struct dead_debug_global_entry compare_type;
  51   /* Hash on the pseudo number.  */
  52   static inline hashval_t hash (const value_type *my);
  53   /* Entries are identical if they refer to the same pseudo.  */
  54   static inline bool equal (const value_type *my, const compare_type *other);
  55   /* Release entries when they're removed.  */
  56   static inline void remove (value_type *p);
  57 };
  58
  59 /* Hash on the pseudo number.  */
  60 inline hashval_t
  61 dead_debug_hash_descr::hash (const value_type *my)
  62 {
  63   return REGNO (my->reg);
  64 }
  65
  66 /* Entries are identical if they refer to the same pseudo.  */
  67 inline bool
  68 dead_debug_hash_descr::equal (const value_type *my, const compare_type *other)
  69 {
  70   return my->reg == other->reg;
  71 }
  72
  73 /* Release entries when they're removed.  */
  74 inline void
  75 dead_debug_hash_descr::remove (value_type *p)
  76 {
  77   XDELETE (p);
  78 }
  79
  80 /* Maintain a global table of pseudos used in debug insns after their
  81    deaths in other blocks, and debug temps their deathpoint values are
  82    to be bound to.  */
  83
  84 struct dead_debug_global
  85 {
  86   /* This hash table that maps pseudos to debug temps.  */
  87   hash_table<dead_debug_hash_descr> *htab;
  88   /* For each entry in htab, the bit corresponding to its REGNO will
  89      be set.  */
  90   bitmap used;
  91 };
  92
  93 /* Node of a linked list of uses of dead REGs in debug insns.  */
  94
  95 struct dead_debug_use
  96 {
  97   df_ref use;
  98   struct dead_debug_use *next;
  99 };
 100
 101 /* Linked list of the above, with a bitmap of the REGs in the
 102    list.  */
 103
 104 struct dead_debug_local
 105 {
 106   /* The first dead_debug_use entry in the list.  */
 107   struct dead_debug_use *head;
 108   /* A pointer to the global tracking data structure.  */
 109   struct dead_debug_global *global;
 110   /* A bitmap that has bits set for each REG used in the
 111      dead_debug_use list, and for each entry in the global hash
 112      table.  */
 113   bitmap used;
 114   /* A bitmap that has bits set for each INSN that is to be
 115      rescanned.  */
 116   bitmap to_rescan;
 117 };
 118
 119 /* This type controls the behavior of dead_debug_insert_temp WRT
 120    UREGNO and INSN.  */
 121
 122 enum debug_temp_where
 123   {
 124     /* Bind a newly-created debug temporary to a REG for UREGNO, and
 125        insert the debug insn before INSN.  REG is expected to die at
 126        INSN.  */
 127     DEBUG_TEMP_BEFORE_WITH_REG = -1,
 128     /* Bind a newly-created debug temporary to the value INSN stores
 129        in REG, and insert the debug insn before INSN.  */
 130     DEBUG_TEMP_BEFORE_WITH_VALUE = 0,
 131     /* Bind a newly-created debug temporary to a REG for UREGNO, and
 132        insert the debug insn after INSN.  REG is expected to be set at
 133        INSN.  */
 134     DEBUG_TEMP_AFTER_WITH_REG = 1,
 135     /* Like DEBUG_TEMP_AFTER_WITH_REG, but force addition of a debug
 136        temporary even if there is just a single debug use.  This is used
 137        on regs that are becoming REG_DEAD on INSN and so uses of the
 138        reg later on are invalid.  */
 139     DEBUG_TEMP_AFTER_WITH_REG_FORCE = 2
 140   };
 141
 142 extern void dead_debug_global_init (struct dead_debug_global *, bitmap);
 143 extern void dead_debug_global_finish (struct dead_debug_global *, bitmap);
 144 extern void dead_debug_local_init (struct dead_debug_local *, bitmap,
 145                                    struct dead_debug_global *);
 146 extern void dead_debug_local_finish (struct dead_debug_local *, bitmap);
 147 extern void dead_debug_add (struct dead_debug_local *, df_ref, unsigned int);
 148 extern int dead_debug_insert_temp (struct dead_debug_local *,
 149                                    unsigned int uregno, rtx insn,
 150                                    enum debug_temp_where);
 151
 152 extern void propagate_for_debug (rtx, rtx, rtx, rtx, basic_block);
 153
 154
 155 #endif /* GCC_VALTRACK_H */