gcc/gimple-range-cache.h

   1 /* Header file for gimple ranger SSA cache.
   2    Copyright (C) 2017-2021 Free Software Foundation, Inc.
   3    Contributed by Andrew MacLeod <amacleod@redhat.com>.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15  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 GCC_SSA_RANGE_CACHE_H
  22 #define GCC_SSA_RANGE_CACHE_H
  23
  24 #include "gimple-range-gori.h"
  25
  26 // Class used to track non-null references of an SSA name.  A vector
  27 // of bitmaps indexed by SSA name is maintained.  When indexed by
  28 // basic block, an on-bit indicates there is a non-null dereference
  29 // for that SSA in that block.
  30
  31 class non_null_ref
  32 {
  33 public:
  34   non_null_ref ();
  35   ~non_null_ref ();
  36   bool non_null_deref_p (tree name, basic_block bb, bool search_dom = true);
  37   bool adjust_range (irange &r, tree name, basic_block bb,
  38                      bool search_dom = true);
  39 private:
  40   vec <bitmap> m_nn;
  41   void process_name (tree name);
  42   bitmap_obstack m_bitmaps;
  43 };
  44
  45 // This class manages a vector of pointers to ssa_block ranges.  It
  46 // provides the basis for the "range on entry" cache for all
  47 // SSA names.
  48
  49 class block_range_cache
  50 {
  51 public:
  52   block_range_cache ();
  53   ~block_range_cache ();
  54
  55   bool set_bb_range (tree name, const_basic_block bb, const irange &r);
  56   bool get_bb_range (irange &r, tree name, const_basic_block bb);
  57   bool bb_range_p (tree name, const_basic_block bb);
  58
  59   void dump (FILE *f);
  60   void dump (FILE *f, basic_block bb, bool print_varying = true);
  61 private:
  62   vec<class ssa_block_ranges *> m_ssa_ranges;
  63   ssa_block_ranges &get_block_ranges (tree name);
  64   ssa_block_ranges *query_block_ranges (tree name);
  65   irange_allocator *m_irange_allocator;
  66   bitmap_obstack m_bitmaps;
  67 };
  68
  69 // This global cache is used with the range engine as markers for what
  70 // has been visited during this incarnation.  Once the ranger evaluates
  71 // a name, it is typically not re-evaluated again.
  72
  73 class ssa_global_cache
  74 {
  75 public:
  76   ssa_global_cache ();
  77   ~ssa_global_cache ();
  78   bool get_global_range (irange &r, tree name) const;
  79   bool set_global_range (tree name, const irange &r);
  80   void clear_global_range (tree name);
  81   void clear ();
  82   void dump (FILE *f = stderr);
  83 private:
  84   vec<irange *> m_tab;
  85   class irange_allocator *m_irange_allocator;
  86 };
  87
  88 // This class provides all the caches a global ranger may need, and makes
  89 // them available for gori-computes to query so outgoing edges can be
  90 // properly calculated.
  91
  92 class ranger_cache : public range_query
  93 {
  94 public:
  95   ranger_cache ();
  96   ~ranger_cache ();
  97
  98   virtual bool range_of_expr (irange &r, tree name, gimple *stmt);
  99   virtual bool range_on_edge (irange &r, edge e, tree expr);
 100   bool block_range (irange &r, basic_block bb, tree name, bool calc = true);
 101
 102   bool get_global_range (irange &r, tree name) const;
 103   bool get_non_stale_global_range (irange &r, tree name);
 104   void set_global_range (tree name, const irange &r);
 105
 106   non_null_ref m_non_null;
 107   gori_compute m_gori;
 108
 109   void dump_bb (FILE *f, basic_block bb);
 110   virtual void dump (FILE *f) OVERRIDE;
 111 private:
 112   ssa_global_cache m_globals;
 113   block_range_cache m_on_entry;
 114   class temporal_cache *m_temporal;
 115   void add_to_update (basic_block bb);
 116   void fill_block_cache (tree name, basic_block bb, basic_block def_bb);
 117   void propagate_cache (tree name);
 118
 119   void range_of_def (irange &r, tree name, basic_block bb = NULL);
 120   void entry_range (irange &r, tree expr, basic_block bb);
 121   void exit_range (irange &r, tree expr, basic_block bb);
 122
 123   void propagate_updated_value (tree name, basic_block bb);
 124
 125   bitmap m_propfail;
 126   vec<basic_block> m_workback;
 127   vec<basic_block> m_update_list;
 128 };
 129
 130 #endif // GCC_SSA_RANGE_CACHE_H