1/* Tree based alias analysis and alias oracle. 2 Copyright (C) 2008 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#include "coretypes.h" 25 26 27/* The points-to solution. 28 29 The points-to solution is a union of pt_vars and the abstract 30 sets specified by the flags. */ 31struct GTY(()) pt_solution 32{ 33 /* Nonzero if points-to analysis couldn't determine where this pointer 34 is pointing to. */ 35 unsigned int anything : 1; 36 37 /* Nonzero if the points-to set includes any global memory. Note that 38 even if this is zero pt_vars can still include global variables. */ 39 unsigned int nonlocal : 1; 40 41 /* Nonzero if the points-to set includes any escaped local variable. */ 42 unsigned int escaped : 1; 43 44 /* Nonzero if the points-to set includes 'nothing', the points-to set 45 includes memory at address NULL. */ 46 unsigned int null : 1; 47 48 49 /* Nonzero if the pt_vars bitmap includes a global variable. */ 50 unsigned int vars_contains_global : 1; 51 52 /* Nonzero if the pt_vars bitmap includes a restrict tag variable. */ 53 unsigned int vars_contains_restrict : 1; 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. */ 63typedef 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} ao_ref; 87 88 89/* In tree-ssa-alias.c */ 90extern void ao_ref_init (ao_ref *, tree); 91extern void ao_ref_init_from_ptr_and_size (ao_ref *, tree, tree); 92extern tree ao_ref_base (ao_ref *); 93extern alias_set_type ao_ref_alias_set (ao_ref *); 94extern bool ptr_deref_may_alias_global_p (tree); 95extern bool refs_may_alias_p (tree, tree); 96extern bool refs_may_alias_p_1 (ao_ref *, ao_ref *, bool); 97extern bool refs_anti_dependent_p (tree, tree); 98extern bool refs_output_dependent_p (tree, tree); 99extern bool ref_maybe_used_by_stmt_p (gimple, tree); 100extern bool stmt_may_clobber_ref_p (gimple, tree); 101extern bool stmt_may_clobber_ref_p_1 (gimple, ao_ref *); 102extern tree get_continuation_for_phi (gimple, ao_ref *, bitmap *); 103extern void *walk_non_aliased_vuses (ao_ref *, tree, 104 void *(*)(ao_ref *, tree, void *), 105 void *(*)(ao_ref *, tree, void *), void *); 106extern unsigned int walk_aliased_vdefs (ao_ref *, tree, 107 bool (*)(ao_ref *, tree, void *), 108 void *, bitmap *); 109extern struct ptr_info_def *get_ptr_info (tree); 110extern void dump_alias_info (FILE *); 111extern void debug_alias_info (void); 112extern void dump_points_to_solution (FILE *, struct pt_solution *); 113extern void dump_points_to_info_for (FILE *, tree); 114extern void debug_points_to_info_for (tree); 115extern void dump_alias_stats (FILE *); 116 117 118/* In tree-ssa-structalias.c */ 119extern unsigned int compute_may_aliases (void); 120extern void delete_alias_heapvars (void); 121extern bool pt_solution_includes_global (struct pt_solution *); 122extern bool pt_solution_includes (struct pt_solution *, const_tree); 123extern bool pt_solutions_intersect (struct pt_solution *, struct pt_solution *); 124extern bool pt_solutions_same_restrict_base (struct pt_solution *, 125 struct pt_solution *); 126extern void pt_solution_reset (struct pt_solution *); 127extern void pt_solution_set (struct pt_solution *, bitmap); 128extern void dump_pta_stats (FILE *); 129 130 131#endif /* TREE_SSA_ALIAS_H */ 132