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