Home | History | Annotate | Download | only in include
      1 /* Tree based alias analysis and alias oracle.
      2    Copyright (C) 2008-2013 Free Software Foundation, Inc.
      3    Contributed by Richard Guenther  <rguenther (at) 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