1 | /* Tree based alias analysis and alias oracle. |
2 | Copyright (C) 2008-2023 Free Software Foundation, Inc. |
3 | Contributed by Richard Guenther <rguenther@suse.de> |
4 | |
5 | This file is part of GCC. |
6 | |
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. |
11 | |
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. |
16 | |
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/>. */ |
20 | |
21 | #ifndef TREE_SSA_ALIAS_H |
22 | #define TREE_SSA_ALIAS_H |
23 | |
24 | /* The points-to solution. |
25 | |
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 |
29 | { |
30 | /* Nonzero if points-to analysis couldn't determine where this pointer |
31 | is pointing to. */ |
32 | unsigned int anything : 1; |
33 | |
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; |
37 | |
38 | /* Nonzero if the points-to set includes the local escaped solution by |
39 | reference. */ |
40 | unsigned int escaped : 1; |
41 | |
42 | /* Nonzero if the points-to set includes the IPA escaped solution by |
43 | reference. */ |
44 | unsigned int ipa_escaped : 1; |
45 | |
46 | /* Nonzero if the points-to set includes 'nothing', the points-to set |
47 | includes memory at address NULL. */ |
48 | unsigned int null : 1; |
49 | |
50 | /* Nonzero if the vars bitmap includes a variable included in 'nonlocal'. */ |
51 | unsigned int vars_contains_nonlocal : 1; |
52 | /* Nonzero if the vars bitmap includes a variable included in 'escaped'. */ |
53 | unsigned int vars_contains_escaped : 1; |
54 | /* Nonzero if the vars bitmap includes a anonymous heap variable that |
55 | escaped the function and thus became global. */ |
56 | unsigned int vars_contains_escaped_heap : 1; |
57 | /* Nonzero if the vars bitmap includes a anonymous variable used to |
58 | represent storage pointed to by a restrict qualified pointer. */ |
59 | unsigned int vars_contains_restrict : 1; |
60 | /* Nonzero if the vars bitmap includes an interposable variable. */ |
61 | unsigned int vars_contains_interposable : 1; |
62 | |
63 | /* Set of variables that this pointer may point to. */ |
64 | bitmap vars; |
65 | }; |
66 | |
67 | |
68 | /* Simplified and cached information about a memory reference tree. |
69 | Used by the alias-oracle internally and externally in alternate |
70 | interfaces. */ |
71 | class ao_ref |
72 | { |
73 | public: |
74 | /* The original full memory reference tree or NULL_TREE if that is |
75 | not available. */ |
76 | tree ref; |
77 | |
78 | /* The following fields are the decomposed reference as returned |
79 | by get_ref_base_and_extent. */ |
80 | /* The base object of the memory reference or NULL_TREE if all of |
81 | the following fields are not yet computed. */ |
82 | tree base; |
83 | /* The offset relative to the base. */ |
84 | poly_int64 offset; |
85 | /* The size of the access. */ |
86 | poly_int64 size; |
87 | /* The maximum possible extent of the access or -1 if unconstrained. */ |
88 | poly_int64 max_size; |
89 | |
90 | /* The alias set of the access or -1 if not yet computed. */ |
91 | alias_set_type ref_alias_set; |
92 | |
93 | /* The alias set of the base object or -1 if not yet computed. */ |
94 | alias_set_type base_alias_set; |
95 | |
96 | /* Whether the memory is considered a volatile access. */ |
97 | bool volatile_p; |
98 | |
99 | bool max_size_known_p () const; |
100 | }; |
101 | |
102 | /* Return true if the maximum size is known, rather than the special -1 |
103 | marker. */ |
104 | |
105 | inline bool |
106 | ao_ref::max_size_known_p () const |
107 | { |
108 | return known_size_p (a: max_size); |
109 | } |
110 | |
111 | /* In tree-ssa-alias.cc */ |
112 | extern void ao_ref_init (ao_ref *, tree); |
113 | extern void ao_ref_init_from_ptr_and_size (ao_ref *, tree, tree); |
114 | extern void ao_ref_init_from_ptr_and_range (ao_ref *, tree, bool, |
115 | poly_int64, poly_int64, |
116 | poly_int64); |
117 | extern tree ao_ref_base (ao_ref *); |
118 | extern alias_set_type ao_ref_alias_set (ao_ref *); |
119 | extern alias_set_type ao_ref_base_alias_set (ao_ref *); |
120 | extern tree ao_ref_alias_ptr_type (ao_ref *); |
121 | extern tree ao_ref_base_alias_ptr_type (ao_ref *); |
122 | extern bool ao_ref_alignment (ao_ref *, unsigned int *, |
123 | unsigned HOST_WIDE_INT *); |
124 | extern bool ptr_deref_may_alias_global_p (tree, bool); |
125 | extern bool ptr_derefs_may_alias_p (tree, tree); |
126 | extern bool ptrs_compare_unequal (tree, tree); |
127 | extern bool ref_may_alias_global_p (tree, bool); |
128 | extern bool ref_may_alias_global_p (ao_ref *, bool); |
129 | extern bool refs_may_alias_p (tree, tree, bool = true); |
130 | extern bool refs_may_alias_p_1 (ao_ref *, ao_ref *, bool); |
131 | extern bool refs_anti_dependent_p (tree, tree); |
132 | extern bool refs_output_dependent_p (tree, tree); |
133 | extern bool ref_maybe_used_by_stmt_p (gimple *, tree, bool = true); |
134 | extern bool ref_maybe_used_by_stmt_p (gimple *, ao_ref *, bool = true); |
135 | extern bool stmt_may_clobber_global_p (gimple *, bool); |
136 | extern bool stmt_may_clobber_ref_p (gimple *, tree, bool = true); |
137 | extern bool stmt_may_clobber_ref_p_1 (gimple *, ao_ref *, bool = true); |
138 | extern bool call_may_clobber_ref_p (gcall *, tree, bool = true); |
139 | extern bool call_may_clobber_ref_p_1 (gcall *, ao_ref *, bool = true); |
140 | extern bool stmt_kills_ref_p (gimple *, tree); |
141 | extern bool stmt_kills_ref_p (gimple *, ao_ref *); |
142 | enum translate_flags |
143 | { TR_TRANSLATE, TR_VALUEIZE_AND_DISAMBIGUATE, TR_DISAMBIGUATE }; |
144 | extern tree get_continuation_for_phi (gimple *, ao_ref *, bool, |
145 | unsigned int &, bitmap *, bool, |
146 | void *(*)(ao_ref *, tree, void *, |
147 | translate_flags *), |
148 | void *, translate_flags |
149 | = TR_VALUEIZE_AND_DISAMBIGUATE); |
150 | extern void *walk_non_aliased_vuses (ao_ref *, tree, bool, |
151 | void *(*)(ao_ref *, tree, void *), |
152 | void *(*)(ao_ref *, tree, void *, |
153 | translate_flags *), |
154 | tree (*)(tree), unsigned &, void *); |
155 | extern int walk_aliased_vdefs (ao_ref *, tree, |
156 | bool (*)(ao_ref *, tree, void *), |
157 | void *, bitmap *, |
158 | bool *function_entry_reached = NULL, |
159 | unsigned int limit = 0); |
160 | extern void dump_alias_info (FILE *); |
161 | extern void debug_alias_info (void); |
162 | extern void dump_points_to_solution (FILE *, struct pt_solution *); |
163 | extern void debug (pt_solution &ref); |
164 | extern void debug (pt_solution *ptr); |
165 | extern void dump_points_to_info_for (FILE *, tree); |
166 | extern void debug_points_to_info_for (tree); |
167 | extern void dump_alias_stats (FILE *); |
168 | |
169 | |
170 | /* In tree-ssa-structalias.cc */ |
171 | extern unsigned int compute_may_aliases (void); |
172 | extern bool pt_solution_empty_p (const pt_solution *); |
173 | extern bool pt_solution_singleton_or_null_p (struct pt_solution *, unsigned *); |
174 | extern bool pt_solution_includes_global (struct pt_solution *, bool); |
175 | extern bool pt_solution_includes (struct pt_solution *, const_tree); |
176 | extern bool pt_solutions_intersect (struct pt_solution *, struct pt_solution *); |
177 | extern void pt_solution_reset (struct pt_solution *); |
178 | extern void pt_solution_set (struct pt_solution *, bitmap, bool); |
179 | extern void pt_solution_set_var (struct pt_solution *, tree); |
180 | |
181 | extern void dump_pta_stats (FILE *); |
182 | |
183 | extern GTY(()) struct pt_solution ipa_escaped_pt; |
184 | |
185 | /* Return true, if the two ranges [POS1, SIZE1] and [POS2, SIZE2] |
186 | overlap. SIZE1 and/or SIZE2 can be (unsigned)-1 in which case the |
187 | range is open-ended. Otherwise return false. */ |
188 | |
189 | inline bool |
190 | ranges_overlap_p (HOST_WIDE_INT pos1, |
191 | unsigned HOST_WIDE_INT size1, |
192 | HOST_WIDE_INT pos2, |
193 | unsigned HOST_WIDE_INT size2) |
194 | { |
195 | if (size1 == 0 || size2 == 0) |
196 | return false; |
197 | if (pos1 >= pos2 |
198 | && (size2 == (unsigned HOST_WIDE_INT)-1 |
199 | || pos1 < (pos2 + (HOST_WIDE_INT) size2))) |
200 | return true; |
201 | if (pos2 >= pos1 |
202 | && (size1 == (unsigned HOST_WIDE_INT)-1 |
203 | || pos2 < (pos1 + (HOST_WIDE_INT) size1))) |
204 | return true; |
205 | |
206 | return false; |
207 | } |
208 | |
209 | |
210 | |
211 | #endif /* TREE_SSA_ALIAS_H */ |
212 | |