gcc/gimple-range-infer.h

   1 /* Header file for gimple range inference.
   2    Copyright (C) 2022 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_GIMPLE_RANGE_SIDE_H
  22 #define GCC_GIMPLE_RANGE_SIDE_H
  23
  24 // Inferred ranges are ranges which are applied to use operands as a by product
  25 // of executing an operation.
  26
  27 // This class manages an on-demand summary of inferred ranges for a statement.
  28 // It can be instantiated as required and provides a list of inferred ranges.
  29 // New inferred ranges should be added in the constructor of this class.
  30
  31 class gimple_infer_range
  32 {
  33 public:
  34   gimple_infer_range (gimple *s);
  35   inline unsigned num () const { return num_args; }
  36   inline tree name (unsigned index) const
  37     { gcc_checking_assert (index < num_args); return m_names[index]; }
  38   inline const vrange& range (unsigned index) const
  39     { gcc_checking_assert (index < num_args); return m_ranges[index]; }
  40   void add_range (tree name, vrange &range);
  41   void add_nonzero (tree name);
  42 private:
  43   unsigned num_args;
  44   static const int size_limit = 10;
  45   tree m_names[size_limit];
  46   Value_Range m_ranges[size_limit];
  47   inline void bump_index () { if (num_args < size_limit - 1) num_args++; }
  48 };
  49
  50 // This class manages a list of inferred ranges for each basic block.
  51 // As inferences are made, they can be registered to a block and later
  52 // queried.  When constructed with a TRUE flag, immediate uses chains are
  53 // followed the first time a name is referenced and block populated if
  54 // there are any inferred ranges.
  55
  56 class infer_range_manager
  57 {
  58 public:
  59   infer_range_manager (bool do_search);
  60   ~infer_range_manager ();
  61   void add_range (tree name, basic_block bb, const vrange &r);
  62   void add_nonzero (tree name, basic_block bb);
  63   bool has_range_p (tree name, basic_block bb);
  64   bool maybe_adjust_range (vrange &r, tree name, basic_block bb);
  65 private:
  66   class exit_range_head
  67   {
  68   public:
  69     bitmap m_names;             // list of names with an outgoing range.
  70     class exit_range *head;
  71     int m_num_ranges;
  72     exit_range *find_ptr (tree name);
  73   };
  74   void register_all_uses (tree name);
  75   vec <exit_range_head> m_on_exit;
  76   const vrange &get_nonzero (tree name);
  77   vec <vrange *> m_nonzero;
  78   bitmap m_seen;
  79   bitmap_obstack m_bitmaps;
  80   struct obstack m_list_obstack;
  81   class obstack_vrange_allocator *m_range_allocator;
  82 };
  83
  84 #endif // GCC_GIMPLE_RANGE_SIDE_H