gcc/gimple-range-infer.h

   1 /* Header file for gimple range inference.
   2    Copyright (C) 2022-2024 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, bool use_rangeops = false);
  35   gimple_infer_range (tree name, vrange &r);
  36   inline unsigned num () const { return num_args; }
  37   inline tree name (unsigned index) const
  38     { gcc_checking_assert (index < num_args); return m_names[index]; }
  39   inline const vrange& range (unsigned index) const
  40     { gcc_checking_assert (index < num_args); return m_ranges[index]; }
  41 private:
  42   void add_range (tree name, vrange &range);
  43   void add_nonzero (tree name);
  44   void check_assume_func (gcall *call);
  45   unsigned num_args;
  46   static const int size_limit = 10;
  47   tree m_names[size_limit];
  48   value_range m_ranges[size_limit];
  49   inline void bump_index () { if (num_args < size_limit - 1) num_args++; }
  50   friend class non_null_wrapper;
  51 };
  52
  53 // This is the basic infer oracle API.  Default functionaility does nothing.
  54
  55 class infer_range_oracle
  56 {
  57 public:
  58   infer_range_oracle () { }
  59   virtual ~infer_range_oracle () { }
  60   virtual void add_ranges (gimple *, gimple_infer_range &) { }
  61   virtual bool has_range_p (basic_block, tree = NULL_TREE) { return false; }
  62   virtual bool maybe_adjust_range (vrange &, tree, basic_block)
  63       { return false; }
  64 };
  65
  66 // This class manages a list of inferred ranges for each basic block.
  67 // As inferences are made, they can be registered to a block and later
  68 // queried.  When constructed with a TRUE flag, immediate uses chains are
  69 // followed the first time a name is referenced and block populated if
  70 // there are any inferred ranges.
  71
  72 class infer_range_manager : public infer_range_oracle
  73 {
  74 public:
  75   infer_range_manager (bool do_search);
  76   virtual ~infer_range_manager ();
  77   virtual void add_ranges (gimple *s, gimple_infer_range &ir);
  78   virtual bool has_range_p (basic_block bb, tree name = NULL_TREE);
  79   virtual bool maybe_adjust_range (vrange &r, tree name, basic_block bb);
  80 private:
  81   void add_range (tree name, gimple *s, const vrange &r);
  82   void add_nonzero (tree name, gimple *s);
  83   class exit_range_head
  84   {
  85   public:
  86     bitmap m_names;             // list of names with an outgoing range.
  87     class exit_range *head;
  88     int m_num_ranges;
  89     exit_range *find_ptr (tree name);
  90   };
  91   void register_all_uses (tree name);
  92   vec <exit_range_head> m_on_exit;
  93   const vrange &get_nonzero (tree name);
  94   vec <vrange *> m_nonzero;
  95   bitmap m_seen;
  96   bitmap_obstack m_bitmaps;
  97   struct obstack m_list_obstack;
  98   class vrange_allocator *m_range_allocator;
  99 };
 100
 101 #endif // GCC_GIMPLE_RANGE_SIDE_H