2015-09-21 Steven G. Kargl <kargl@gcc.gnu.org>
[official-gcc.git] / gcc / tree-ssa-alias.h
blob67d9bcb17509dea5655848418a60fba01c147f4f
1 /* Tree based alias analysis and alias oracle.
2 Copyright (C) 2008-2015 Free Software Foundation, Inc.
3 Contributed by Richard Guenther <rguenther@suse.de>
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify
8 under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 #ifndef TREE_SSA_ALIAS_H
22 #define TREE_SSA_ALIAS_H
24 /* The points-to solution.
26 The points-to solution is a union of pt_vars and the abstract
27 sets specified by the flags. */
28 struct GTY(()) pt_solution
30 /* Nonzero if points-to analysis couldn't determine where this pointer
31 is pointing to. */
32 unsigned int anything : 1;
34 /* Nonzero if the points-to set includes any global memory. Note that
35 even if this is zero pt_vars can still include global variables. */
36 unsigned int nonlocal : 1;
38 /* Nonzero if the points-to set includes the local escaped solution by
39 reference. */
40 unsigned int escaped : 1;
42 /* Nonzero if the points-to set includes the IPA escaped solution by
43 reference. */
44 unsigned int ipa_escaped : 1;
46 /* Nonzero if the points-to set includes 'nothing', the points-to set
47 includes memory at address NULL. */
48 unsigned int null : 1;
51 /* Nonzero if the vars bitmap includes a variable included in 'nonlocal'. */
52 unsigned int vars_contains_nonlocal : 1;
53 /* Nonzero if the vars bitmap includes a variable included in 'escaped'. */
54 unsigned int vars_contains_escaped : 1;
55 /* Nonzero if the vars bitmap includes a anonymous heap variable that
56 escaped the function and thus became global. */
57 unsigned int vars_contains_escaped_heap : 1;
59 /* Set of variables that this pointer may point to. */
60 bitmap vars;
64 /* Simplified and cached information about a memory reference tree.
65 Used by the alias-oracle internally and externally in alternate
66 interfaces. */
67 struct ao_ref
69 /* The original full memory reference tree or NULL_TREE if that is
70 not available. */
71 tree ref;
73 /* The following fields are the decomposed reference as returned
74 by get_ref_base_and_extent. */
75 /* The base object of the memory reference or NULL_TREE if all of
76 the following fields are not yet computed. */
77 tree base;
78 /* The offset relative to the base. */
79 HOST_WIDE_INT offset;
80 /* The size of the access. */
81 HOST_WIDE_INT size;
82 /* The maximum possible extent of the access or -1 if unconstrained. */
83 HOST_WIDE_INT max_size;
85 /* The alias set of the access or -1 if not yet computed. */
86 alias_set_type ref_alias_set;
88 /* The alias set of the base object or -1 if not yet computed. */
89 alias_set_type base_alias_set;
91 /* Whether the memory is considered a volatile access. */
92 bool volatile_p;
96 /* In tree-ssa-alias.c */
97 extern void ao_ref_init (ao_ref *, tree);
98 extern void ao_ref_init_from_ptr_and_size (ao_ref *, tree, tree);
99 extern tree ao_ref_base (ao_ref *);
100 extern alias_set_type ao_ref_alias_set (ao_ref *);
101 extern alias_set_type ao_ref_base_alias_set (ao_ref *);
102 extern bool ptr_deref_may_alias_global_p (tree);
103 extern bool ptr_derefs_may_alias_p (tree, tree);
104 extern bool ref_may_alias_global_p (tree);
105 extern bool ref_may_alias_global_p (ao_ref *);
106 extern bool refs_may_alias_p (tree, tree);
107 extern bool refs_may_alias_p_1 (ao_ref *, ao_ref *, bool);
108 extern bool refs_anti_dependent_p (tree, tree);
109 extern bool refs_output_dependent_p (tree, tree);
110 extern bool ref_maybe_used_by_stmt_p (gimple *, tree);
111 extern bool ref_maybe_used_by_stmt_p (gimple *, ao_ref *);
112 extern bool stmt_may_clobber_global_p (gimple *);
113 extern bool stmt_may_clobber_ref_p (gimple *, tree);
114 extern bool stmt_may_clobber_ref_p_1 (gimple *, ao_ref *);
115 extern bool call_may_clobber_ref_p (gcall *, tree);
116 extern bool call_may_clobber_ref_p_1 (gcall *, ao_ref *);
117 extern bool stmt_kills_ref_p (gimple *, tree);
118 extern bool stmt_kills_ref_p (gimple *, ao_ref *);
119 extern tree get_continuation_for_phi (gimple *, ao_ref *,
120 unsigned int *, bitmap *, bool,
121 void *(*)(ao_ref *, tree, void *, bool),
122 void *);
123 extern void *walk_non_aliased_vuses (ao_ref *, tree,
124 void *(*)(ao_ref *, tree,
125 unsigned int, void *),
126 void *(*)(ao_ref *, tree, void *, bool),
127 tree (*)(tree),
128 void *);
129 extern unsigned int walk_aliased_vdefs (ao_ref *, tree,
130 bool (*)(ao_ref *, tree, void *),
131 void *, bitmap *,
132 bool *function_entry_reached = NULL);
133 extern void dump_alias_info (FILE *);
134 extern void debug_alias_info (void);
135 extern void dump_points_to_solution (FILE *, struct pt_solution *);
136 extern void debug (pt_solution &ref);
137 extern void debug (pt_solution *ptr);
138 extern void dump_points_to_info_for (FILE *, tree);
139 extern void debug_points_to_info_for (tree);
140 extern void dump_alias_stats (FILE *);
143 /* In tree-ssa-structalias.c */
144 extern unsigned int compute_may_aliases (void);
145 extern bool pt_solution_empty_p (struct pt_solution *);
146 extern bool pt_solution_singleton_p (struct pt_solution *, unsigned *);
147 extern bool pt_solution_includes_global (struct pt_solution *);
148 extern bool pt_solution_includes (struct pt_solution *, const_tree);
149 extern bool pt_solutions_intersect (struct pt_solution *, struct pt_solution *);
150 extern void pt_solution_reset (struct pt_solution *);
151 extern void pt_solution_set (struct pt_solution *, bitmap, bool);
152 extern void pt_solution_set_var (struct pt_solution *, tree);
154 extern void dump_pta_stats (FILE *);
156 extern GTY(()) struct pt_solution ipa_escaped_pt;
158 /* Return true, if the two ranges [POS1, SIZE1] and [POS2, SIZE2]
159 overlap. SIZE1 and/or SIZE2 can be (unsigned)-1 in which case the
160 range is open-ended. Otherwise return false. */
162 static inline bool
163 ranges_overlap_p (HOST_WIDE_INT pos1,
164 unsigned HOST_WIDE_INT size1,
165 HOST_WIDE_INT pos2,
166 unsigned HOST_WIDE_INT size2)
168 if (pos1 >= pos2
169 && (size2 == (unsigned HOST_WIDE_INT)-1
170 || pos1 < (pos2 + (HOST_WIDE_INT) size2)))
171 return true;
172 if (pos2 >= pos1
173 && (size1 == (unsigned HOST_WIDE_INT)-1
174 || pos2 < (pos1 + (HOST_WIDE_INT) size1)))
175 return true;
177 return false;
182 #endif /* TREE_SSA_ALIAS_H */