1 /* Tree based alias analysis and alias oracle. 2 Copyright (C) 2008-2013 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 51 /* Nonzero if the pt_vars bitmap includes a global variable. */ 52 unsigned int vars_contains_global : 1; 53 54 55 /* Set of variables that this pointer may point to. */ 56 bitmap vars; 57 }; 58 59 60 /* Simplified and cached information about a memory reference tree. 61 Used by the alias-oracle internally and externally in alternate 62 interfaces. */ 63 typedef struct ao_ref_s 64 { 65 /* The original full memory reference tree or NULL_TREE if that is 66 not available. */ 67 tree ref; 68 69 /* The following fields are the decomposed reference as returned 70 by get_ref_base_and_extent. */ 71 /* The base object of the memory reference or NULL_TREE if all of 72 the following fields are not yet computed. */ 73 tree base; 74 /* The offset relative to the base. */ 75 HOST_WIDE_INT offset; 76 /* The size of the access. */ 77 HOST_WIDE_INT size; 78 /* The maximum possible extent of the access or -1 if unconstrained. */ 79 HOST_WIDE_INT max_size; 80 81 /* The alias set of the access or -1 if not yet computed. */ 82 alias_set_type ref_alias_set; 83 84 /* The alias set of the base object or -1 if not yet computed. */ 85 alias_set_type base_alias_set; 86 87 /* Whether the memory is considered a volatile access. */ 88 bool volatile_p; 89 } ao_ref; 90 91 92 /* In tree-ssa-alias.c */ 93 extern void ao_ref_init (ao_ref *, tree); 94 extern void ao_ref_init_from_ptr_and_size (ao_ref *, tree, tree); 95 extern tree ao_ref_base (ao_ref *); 96 extern alias_set_type ao_ref_alias_set (ao_ref *); 97 extern bool ptr_deref_may_alias_global_p (tree); 98 extern bool ptr_derefs_may_alias_p (tree, tree); 99 extern bool ref_may_alias_global_p (tree); 100 extern bool refs_may_alias_p (tree, tree); 101 extern bool refs_may_alias_p_1 (ao_ref *, ao_ref *, bool); 102 extern bool refs_anti_dependent_p (tree, tree); 103 extern bool refs_output_dependent_p (tree, tree); 104 extern bool ref_maybe_used_by_stmt_p (gimple, tree); 105 extern bool stmt_may_clobber_global_p (gimple); 106 extern bool stmt_may_clobber_ref_p (gimple, tree); 107 extern bool stmt_may_clobber_ref_p_1 (gimple, ao_ref *); 108 extern bool call_may_clobber_ref_p (gimple, tree); 109 extern bool stmt_kills_ref_p (gimple, tree); 110 extern tree get_continuation_for_phi (gimple, ao_ref *, 111 unsigned int *, bitmap *, bool); 112 extern void *walk_non_aliased_vuses (ao_ref *, tree, 113 void *(*)(ao_ref *, tree, 114 unsigned int, void *), 115 void *(*)(ao_ref *, tree, void *), void *); 116 extern unsigned int walk_aliased_vdefs (ao_ref *, tree, 117 bool (*)(ao_ref *, tree, void *), 118 void *, bitmap *); 119 extern struct ptr_info_def *get_ptr_info (tree); 120 extern void dump_alias_info (FILE *); 121 extern void debug_alias_info (void); 122 extern void dump_points_to_solution (FILE *, struct pt_solution *); 123 extern void dump_points_to_info_for (FILE *, tree); 124 extern void debug_points_to_info_for (tree); 125 extern void dump_alias_stats (FILE *); 126 127 128 /* In tree-ssa-structalias.c */ 129 extern unsigned int compute_may_aliases (void); 130 extern bool pt_solution_empty_p (struct pt_solution *); 131 extern bool pt_solution_singleton_p (struct pt_solution *, unsigned *); 132 extern bool pt_solution_includes_global (struct pt_solution *); 133 extern bool pt_solution_includes (struct pt_solution *, const_tree); 134 extern bool pt_solutions_intersect (struct pt_solution *, struct pt_solution *); 135 extern void pt_solution_reset (struct pt_solution *); 136 extern void pt_solution_set (struct pt_solution *, bitmap, bool); 137 extern void pt_solution_set_var (struct pt_solution *, tree); 138 139 extern void dump_pta_stats (FILE *); 140 141 extern GTY(()) struct pt_solution ipa_escaped_pt; 142 143 144 #endif /* TREE_SSA_ALIAS_H */ 145