Retro68/gcc/gcc/gimple-range-cache.h
2022-10-27 20:55:19 +02:00

161 lines
5.2 KiB
C++

/* Header file for gimple ranger SSA cache.
Copyright (C) 2017-2022 Free Software Foundation, Inc.
Contributed by Andrew MacLeod <amacleod@redhat.com>.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, 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 GCC_SSA_RANGE_CACHE_H
#define GCC_SSA_RANGE_CACHE_H
#include "gimple-range-gori.h"
// Class used to track non-null references of an SSA name. A vector
// of bitmaps indexed by SSA name is maintained. When indexed by
// basic block, an on-bit indicates there is a non-null dereference
// for that SSA in that block.
class non_null_ref
{
public:
non_null_ref ();
~non_null_ref ();
bool non_null_deref_p (tree name, basic_block bb, bool search_dom = true);
bool adjust_range (irange &r, tree name, basic_block bb,
bool search_dom = true);
bool set_nonnull (basic_block bb, tree name);
private:
vec <bitmap> m_nn;
void process_name (tree name);
bitmap_obstack m_bitmaps;
};
// If NAME has a non-null dereference in block BB, adjust R with the
// non-zero information from non_null_deref_p, and return TRUE. If
// SEARCH_DOM is true, non_null_deref_p should search the dominator tree.
inline bool
non_null_ref::adjust_range (irange &r, tree name, basic_block bb,
bool search_dom)
{
// Non-call exceptions mean we could throw in the middle of the
// block, so just punt on those for now.
if (cfun->can_throw_non_call_exceptions)
return false;
// We only care about the null / non-null property of pointers.
if (!POINTER_TYPE_P (TREE_TYPE (name)))
return false;
if (r.undefined_p () || r.lower_bound () != 0 || r.upper_bound () == 0)
return false;
// Check if pointers have any non-null dereferences.
if (non_null_deref_p (name, bb, search_dom))
{
// Remove zero from the range.
unsigned prec = TYPE_PRECISION (TREE_TYPE (name));
r.intersect (wi::one (prec), wi::max_value (prec, UNSIGNED));
return true;
}
return false;
}
// This class manages a vector of pointers to ssa_block ranges. It
// provides the basis for the "range on entry" cache for all
// SSA names.
class block_range_cache
{
public:
block_range_cache ();
~block_range_cache ();
bool set_bb_range (tree name, const_basic_block bb, const irange &r);
bool get_bb_range (irange &r, tree name, const_basic_block bb);
bool bb_range_p (tree name, const_basic_block bb);
void dump (FILE *f);
void dump (FILE *f, basic_block bb, bool print_varying = true);
private:
vec<class ssa_block_ranges *> m_ssa_ranges;
ssa_block_ranges &get_block_ranges (tree name);
ssa_block_ranges *query_block_ranges (tree name);
irange_allocator *m_irange_allocator;
bitmap_obstack m_bitmaps;
};
// This global cache is used with the range engine as markers for what
// has been visited during this incarnation. Once the ranger evaluates
// a name, it is typically not re-evaluated again.
class ssa_global_cache
{
public:
ssa_global_cache ();
~ssa_global_cache ();
bool get_global_range (irange &r, tree name) const;
bool set_global_range (tree name, const irange &r);
void clear_global_range (tree name);
void clear ();
void dump (FILE *f = stderr);
private:
vec<irange *> m_tab;
class irange_allocator *m_irange_allocator;
};
// This class provides all the caches a global ranger may need, and makes
// them available for gori-computes to query so outgoing edges can be
// properly calculated.
class ranger_cache : public range_query
{
public:
ranger_cache (int not_executable_flag);
~ranger_cache ();
virtual bool range_of_expr (irange &r, tree name, gimple *stmt);
virtual bool range_on_edge (irange &r, edge e, tree expr);
bool block_range (irange &r, basic_block bb, tree name, bool calc = true);
bool range_from_dom (irange &r, tree name, basic_block bb);
bool get_global_range (irange &r, tree name) const;
bool get_global_range (irange &r, tree name, bool &current_p);
void set_global_range (tree name, const irange &r);
void propagate_updated_value (tree name, basic_block bb);
void block_apply_nonnull (gimple *s);
void update_to_nonnull (basic_block bb, tree name);
non_null_ref m_non_null;
gori_compute m_gori;
void dump_bb (FILE *f, basic_block bb);
virtual void dump (FILE *f) OVERRIDE;
private:
ssa_global_cache m_globals;
block_range_cache m_on_entry;
class temporal_cache *m_temporal;
void fill_block_cache (tree name, basic_block bb, basic_block def_bb);
void propagate_cache (tree name);
void range_of_def (irange &r, tree name, basic_block bb = NULL);
void entry_range (irange &r, tree expr, basic_block bb);
void exit_range (irange &r, tree expr, basic_block bb);
vec<basic_block> m_workback;
class update_list *m_update;
};
#endif // GCC_SSA_RANGE_CACHE_H