1/* Infrastructure for tracking user variable locations and values
2 throughout compilation.
3 Copyright (C) 2010-2017 Free Software Foundation, Inc.
4 Contributed by Alexandre Oliva <aoliva@redhat.com>.
5
6This file is part of GCC.
7
8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
10Software Foundation; either version 3, or (at your option) any later
11version.
12
13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16for more details.
17
18You should have received a copy of the GNU General Public License
19along 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/* Debug uses of dead regs. */
26
27/* Entry that maps a dead pseudo (REG) used in a debug insns that dies
28 at different blocks to the debug temp (DTEMP) it was replaced
29 with. */
30
31struct dead_debug_global_entry
32{
33 rtx reg;
34 rtx dtemp;
35};
36
37/* Descriptor for hash_table to hash by dead_debug_global_entry's REG
38 and map to DTEMP. */
39
40struct dead_debug_hash_descr : free_ptr_hash <dead_debug_global_entry>
41{
42 /* Hash on the pseudo number. */
43 static inline hashval_t hash (const dead_debug_global_entry *my);
44 /* Entries are identical if they refer to the same pseudo. */
45 static inline bool equal (const dead_debug_global_entry *my,
46 const dead_debug_global_entry *other);
47};
48
49/* Hash on the pseudo number. */
50inline hashval_t
51dead_debug_hash_descr::hash (const dead_debug_global_entry *my)
52{
53 return REGNO (my->reg);
54}
55
56/* Entries are identical if they refer to the same pseudo. */
57inline bool
58dead_debug_hash_descr::equal (const dead_debug_global_entry *my,
59 const dead_debug_global_entry *other)
60{
61 return my->reg == other->reg;
62}
63
64/* Maintain a global table of pseudos used in debug insns after their
65 deaths in other blocks, and debug temps their deathpoint values are
66 to be bound to. */
67
68struct dead_debug_global
69{
70 /* This hash table that maps pseudos to debug temps. */
71 hash_table<dead_debug_hash_descr> *htab;
72 /* For each entry in htab, the bit corresponding to its REGNO will
73 be set. */
74 bitmap used;
75};
76
77/* Node of a linked list of uses of dead REGs in debug insns. */
78
79struct dead_debug_use
80{
81 df_ref use;
82 struct dead_debug_use *next;
83};
84
85/* Linked list of the above, with a bitmap of the REGs in the
86 list. */
87
88struct dead_debug_local
89{
90 /* The first dead_debug_use entry in the list. */
91 struct dead_debug_use *head;
92 /* A pointer to the global tracking data structure. */
93 struct dead_debug_global *global;
94 /* A bitmap that has bits set for each REG used in the
95 dead_debug_use list, and for each entry in the global hash
96 table. */
97 bitmap used;
98 /* A bitmap that has bits set for each INSN that is to be
99 rescanned. */
100 bitmap to_rescan;
101};
102
103/* This type controls the behavior of dead_debug_insert_temp WRT
104 UREGNO and INSN. */
105
106enum debug_temp_where
107 {
108 /* Bind a newly-created debug temporary to a REG for UREGNO, and
109 insert the debug insn before INSN. REG is expected to die at
110 INSN. */
111 DEBUG_TEMP_BEFORE_WITH_REG = -1,
112 /* Bind a newly-created debug temporary to the value INSN stores
113 in REG, and insert the debug insn before INSN. */
114 DEBUG_TEMP_BEFORE_WITH_VALUE = 0,
115 /* Bind a newly-created debug temporary to a REG for UREGNO, and
116 insert the debug insn after INSN. REG is expected to be set at
117 INSN. */
118 DEBUG_TEMP_AFTER_WITH_REG = 1,
119 /* Like DEBUG_TEMP_AFTER_WITH_REG, but force addition of a debug
120 temporary even if there is just a single debug use. This is used
121 on regs that are becoming REG_DEAD on INSN and so uses of the
122 reg later on are invalid. */
123 DEBUG_TEMP_AFTER_WITH_REG_FORCE = 2
124 };
125
126extern void dead_debug_global_init (struct dead_debug_global *, bitmap);
127extern void dead_debug_global_finish (struct dead_debug_global *, bitmap);
128extern void dead_debug_local_init (struct dead_debug_local *, bitmap,
129 struct dead_debug_global *);
130extern void dead_debug_local_finish (struct dead_debug_local *, bitmap);
131extern void dead_debug_add (struct dead_debug_local *, df_ref, unsigned int);
132extern int dead_debug_insert_temp (struct dead_debug_local *,
133 unsigned int uregno, rtx_insn *insn,
134 enum debug_temp_where);
135
136extern void propagate_for_debug (rtx_insn *, rtx_insn *, rtx, rtx, basic_block);
137
138
139#endif /* GCC_VALTRACK_H */
140