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/* Tree based alias analysis and alias oracle.
Copyright (C) 2008-2021 Free Software Foundation, Inc.
Contributed by Richard Guenther <rguenther@suse.de>
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
GCC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
#ifndef TREE_SSA_ALIAS_H
#define TREE_SSA_ALIAS_H
/* The points-to solution.
The points-to solution is a union of pt_vars and the abstract
sets specified by the flags. */
struct GTY(()) pt_solution
{
/* Nonzero if points-to analysis couldn't determine where this pointer
is pointing to. */
unsigned int anything : 1;
/* Nonzero if the points-to set includes any global memory. Note that
even if this is zero pt_vars can still include global variables. */
unsigned int nonlocal : 1;
/* Nonzero if the points-to set includes the local escaped solution by
reference. */
unsigned int escaped : 1;
/* Nonzero if the points-to set includes the IPA escaped solution by
reference. */
unsigned int ipa_escaped : 1;
/* Nonzero if the points-to set includes 'nothing', the points-to set
includes memory at address NULL. */
unsigned int null : 1;
/* Nonzero if the vars bitmap includes a variable included in 'nonlocal'. */
unsigned int vars_contains_nonlocal : 1;
/* Nonzero if the vars bitmap includes a variable included in 'escaped'. */
unsigned int vars_contains_escaped : 1;
/* Nonzero if the vars bitmap includes a anonymous heap variable that
escaped the function and thus became global. */
unsigned int vars_contains_escaped_heap : 1;
/* Nonzero if the vars bitmap includes a anonymous variable used to
represent storage pointed to by a restrict qualified pointer. */
unsigned int vars_contains_restrict : 1;
/* Nonzero if the vars bitmap includes an interposable variable. */
unsigned int vars_contains_interposable : 1;
/* Set of variables that this pointer may point to. */
bitmap vars;
};
/* Simplified and cached information about a memory reference tree.
Used by the alias-oracle internally and externally in alternate
interfaces. */
class ao_ref
{
public:
/* The original full memory reference tree or NULL_TREE if that is
not available. */
tree ref;
/* The following fields are the decomposed reference as returned
by get_ref_base_and_extent. */
/* The base object of the memory reference or NULL_TREE if all of
the following fields are not yet computed. */
tree base;
/* The offset relative to the base. */
poly_int64 offset;
/* The size of the access. */
poly_int64 size;
/* The maximum possible extent of the access or -1 if unconstrained. */
poly_int64 max_size;
/* The alias set of the access or -1 if not yet computed. */
alias_set_type ref_alias_set;
/* The alias set of the base object or -1 if not yet computed. */
alias_set_type base_alias_set;
/* Whether the memory is considered a volatile access. */
bool volatile_p;
bool max_size_known_p () const;
};
/* Return true if the maximum size is known, rather than the special -1
marker. */
inline bool
ao_ref::max_size_known_p () const
{
return known_size_p (max_size);
}
/* In tree-ssa-alias.c */
extern void ao_ref_init (ao_ref *, tree);
extern void ao_ref_init_from_ptr_and_size (ao_ref *, tree, tree);
extern tree ao_ref_base (ao_ref *);
extern alias_set_type ao_ref_alias_set (ao_ref *);
extern alias_set_type ao_ref_base_alias_set (ao_ref *);
extern tree ao_ref_alias_ptr_type (ao_ref *);
extern tree ao_ref_base_alias_ptr_type (ao_ref *);
extern bool ptr_deref_may_alias_global_p (tree);
extern bool ptr_derefs_may_alias_p (tree, tree);
extern bool ptrs_compare_unequal (tree, tree);
extern bool ref_may_alias_global_p (tree);
extern bool ref_may_alias_global_p (ao_ref *);
extern bool refs_may_alias_p (tree, tree, bool = true);
extern bool refs_may_alias_p_1 (ao_ref *, ao_ref *, bool);
extern bool refs_anti_dependent_p (tree, tree);
extern bool refs_output_dependent_p (tree, tree);
extern bool ref_maybe_used_by_stmt_p (gimple *, tree, bool = true);
extern bool ref_maybe_used_by_stmt_p (gimple *, ao_ref *, bool = true);
extern bool stmt_may_clobber_global_p (gimple *);
extern bool stmt_may_clobber_ref_p (gimple *, tree, bool = true);
extern bool stmt_may_clobber_ref_p_1 (gimple *, ao_ref *, bool = true);
extern bool call_may_clobber_ref_p (gcall *, tree, bool = true);
extern bool call_may_clobber_ref_p_1 (gcall *, ao_ref *, bool = true);
extern bool stmt_kills_ref_p (gimple *, tree);
extern bool stmt_kills_ref_p (gimple *, ao_ref *);
enum translate_flags
{ TR_TRANSLATE, TR_VALUEIZE_AND_DISAMBIGUATE, TR_DISAMBIGUATE };
extern tree get_continuation_for_phi (gimple *, ao_ref *, bool,
unsigned int &, bitmap *, bool,
void *(*)(ao_ref *, tree, void *,
translate_flags *),
void *, translate_flags
= TR_VALUEIZE_AND_DISAMBIGUATE);
extern void *walk_non_aliased_vuses (ao_ref *, tree, bool,
void *(*)(ao_ref *, tree, void *),
void *(*)(ao_ref *, tree, void *,
translate_flags *),
tree (*)(tree), unsigned &, void *);
extern int walk_aliased_vdefs (ao_ref *, tree,
bool (*)(ao_ref *, tree, void *),
void *, bitmap *,
bool *function_entry_reached = NULL,
unsigned int limit = 0);
extern void dump_alias_info (FILE *);
extern void debug_alias_info (void);
extern void dump_points_to_solution (FILE *, struct pt_solution *);
extern void debug (pt_solution &ref);
extern void debug (pt_solution *ptr);
extern void dump_points_to_info_for (FILE *, tree);
extern void debug_points_to_info_for (tree);
extern void dump_alias_stats (FILE *);
/* In tree-ssa-structalias.c */
extern unsigned int compute_may_aliases (void);
extern bool pt_solution_empty_p (const pt_solution *);
extern bool pt_solution_singleton_or_null_p (struct pt_solution *, unsigned *);
extern bool pt_solution_includes_global (struct pt_solution *);
extern bool pt_solution_includes (struct pt_solution *, const_tree);
extern bool pt_solutions_intersect (struct pt_solution *, struct pt_solution *);
extern void pt_solution_reset (struct pt_solution *);
extern void pt_solution_set (struct pt_solution *, bitmap, bool);
extern void pt_solution_set_var (struct pt_solution *, tree);
extern void dump_pta_stats (FILE *);
extern GTY(()) struct pt_solution ipa_escaped_pt;
/* Return true, if the two ranges [POS1, SIZE1] and [POS2, SIZE2]
overlap. SIZE1 and/or SIZE2 can be (unsigned)-1 in which case the
range is open-ended. Otherwise return false. */
static inline bool
ranges_overlap_p (HOST_WIDE_INT pos1,
unsigned HOST_WIDE_INT size1,
HOST_WIDE_INT pos2,
unsigned HOST_WIDE_INT size2)
{
if (size1 == 0 || size2 == 0)
return false;
if (pos1 >= pos2
&& (size2 == (unsigned HOST_WIDE_INT)-1
|| pos1 < (pos2 + (HOST_WIDE_INT) size2)))
return true;
if (pos2 >= pos1
&& (size1 == (unsigned HOST_WIDE_INT)-1
|| pos2 < (pos1 + (HOST_WIDE_INT) size1)))
return true;
return false;
}
#endif /* TREE_SSA_ALIAS_H */