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> 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. */ 28struct 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 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; 58 59 /* Set of variables that this pointer may point to. */ 60 bitmap vars; 61}; 62 63 64/* Simplified and cached information about a memory reference tree. 65 Used by the alias-oracle internally and externally in alternate 66 interfaces. */ 67struct ao_ref 68{ 69 /* The original full memory reference tree or NULL_TREE if that is 70 not available. */ 71 tree ref; 72 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; 84 85 /* The alias set of the access or -1 if not yet computed. */ 86 alias_set_type ref_alias_set; 87 88 /* The alias set of the base object or -1 if not yet computed. */ 89 alias_set_type base_alias_set; 90 91 /* Whether the memory is considered a volatile access. */ 92 bool volatile_p; 93}; 94 95 96/* In tree-ssa-alias.c */ 97extern void ao_ref_init (ao_ref *, tree); 98extern void ao_ref_init_from_ptr_and_size (ao_ref *, tree, tree); 99extern tree ao_ref_base (ao_ref *); 100extern alias_set_type ao_ref_alias_set (ao_ref *); 101extern alias_set_type ao_ref_base_alias_set (ao_ref *); 102extern bool ptr_deref_may_alias_global_p (tree); 103extern bool ptr_derefs_may_alias_p (tree, tree); 104extern bool ref_may_alias_global_p (tree); 105extern bool ref_may_alias_global_p (ao_ref *); 106extern bool refs_may_alias_p (tree, tree); 107extern bool refs_may_alias_p_1 (ao_ref *, ao_ref *, bool); 108extern bool refs_anti_dependent_p (tree, tree); 109extern bool refs_output_dependent_p (tree, tree); 110extern bool ref_maybe_used_by_stmt_p (gimple, tree); 111extern bool ref_maybe_used_by_stmt_p (gimple, ao_ref *); 112extern bool stmt_may_clobber_global_p (gimple); 113extern bool stmt_may_clobber_ref_p (gimple, tree); 114extern bool stmt_may_clobber_ref_p_1 (gimple, ao_ref *); 115extern bool call_may_clobber_ref_p (gcall *, tree); 116extern bool call_may_clobber_ref_p_1 (gcall *, ao_ref *); 117extern bool stmt_kills_ref_p (gimple, tree); 118extern bool stmt_kills_ref_p (gimple, ao_ref *); 119extern tree get_continuation_for_phi (gimple, ao_ref *, 120 unsigned int *, bitmap *, bool, 121 void *(*)(ao_ref *, tree, void *, bool), 122 void *); 123extern 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 *); 129extern unsigned int walk_aliased_vdefs (ao_ref *, tree, 130 bool (*)(ao_ref *, tree, void *), 131 void *, bitmap *, 132 bool *function_entry_reached = NULL); 133extern void dump_alias_info (FILE *); 134extern void debug_alias_info (void); 135extern void dump_points_to_solution (FILE *, struct pt_solution *); 136extern void debug (pt_solution &ref); 137extern void debug (pt_solution *ptr); 138extern void dump_points_to_info_for (FILE *, tree); 139extern void debug_points_to_info_for (tree); 140extern void dump_alias_stats (FILE *); 141 142 143/* In tree-ssa-structalias.c */ 144extern unsigned int compute_may_aliases (void); 145extern bool pt_solution_empty_p (struct pt_solution *); 146extern bool pt_solution_singleton_p (struct pt_solution *, unsigned *); 147extern bool pt_solution_includes_global (struct pt_solution *); 148extern bool pt_solution_includes (struct pt_solution *, const_tree); 149extern bool pt_solutions_intersect (struct pt_solution *, struct pt_solution *); 150extern void pt_solution_reset (struct pt_solution *); 151extern void pt_solution_set (struct pt_solution *, bitmap, bool); 152extern void pt_solution_set_var (struct pt_solution *, tree); 153 154extern void dump_pta_stats (FILE *); 155 156extern GTY(()) struct pt_solution ipa_escaped_pt; 157 158/* 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. */ 161 162static inline bool 163ranges_overlap_p (HOST_WIDE_INT pos1, 164 unsigned HOST_WIDE_INT size1, 165 HOST_WIDE_INT pos2, 166 unsigned HOST_WIDE_INT size2) 167{ 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; 176 177 return false; 178} 179 180 181 182#endif /* TREE_SSA_ALIAS_H */ 183