gcc/gimple-range-fold.h

   1 /* Header file for the GIMPLE fold_using_range interface.
   2    Copyright (C) 2019-2023 Free Software Foundation, Inc.
   3    Contributed by Andrew MacLeod <amacleod@redhat.com>
   4    and Aldy Hernandez <aldyh@redhat.com>.
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16  for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #ifndef GCC_GIMPLE_RANGE_FOLD_H
  23 #define GCC_GIMPLE_RANGE_FOLD_H
  24
  25 // This file is the main include point for gimple range folding.
  26 // These routines will fold stmt S into the result range R.
  27 // Any ssa_names on the stmt will be calculated using the range_query
  28 // parameter via a call to range_of_expr.
  29 // If no range_query is provided, current global range info will be used.
  30 // The second variation specifies an edge, and stmt S is recalculated as if
  31 // it appeared on that edge.
  32
  33 // Fold stmt S into range R using range query Q.
  34 bool fold_range (vrange &r, gimple *s, range_query *q = NULL);
  35 // Recalculate stmt S into R using range query Q as if it were on edge ON_EDGE.
  36 bool fold_range (vrange &v, gimple *s, edge on_edge, range_query *q = NULL);
  37
  38 // These routines the operands to be specified when manually folding.
  39 // Any excess queries will be drawn from the current range_query.
  40 bool fold_range (vrange &r, gimple *s, vrange &r1);
  41 bool fold_range (vrange &r, gimple *s, vrange &r1, vrange &r2);
  42 bool fold_range (vrange &r, gimple *s, unsigned num_elements, vrange **vector);
  43
  44 // Return the type of range which statement S calculates.  If the type is
  45 // unsupported or no type can be determined, return NULL_TREE.
  46
  47 inline tree
  48 gimple_range_type (const gimple *s)
  49 {
  50   tree lhs = gimple_get_lhs (s);
  51   tree type = NULL_TREE;
  52   if (lhs)
  53     type = TREE_TYPE (lhs);
  54   else
  55     {
  56       enum gimple_code code = gimple_code (s);
  57       if (code == GIMPLE_COND)
  58         type = boolean_type_node;
  59       else if (code == GIMPLE_PHI)
  60         type = TREE_TYPE (gimple_phi_result (s));
  61       else if (code == GIMPLE_CALL)
  62         {
  63           type = gimple_call_fntype (s);
  64           // If it has a type, get the return type.
  65           if (type)
  66             type = TREE_TYPE (type);
  67         }
  68     }
  69   if (type && Value_Range::supports_type_p (type))
  70     return type;
  71   return NULL_TREE;
  72 }
  73
  74 // Return EXP if it is an SSA_NAME with a type supported by gimple ranges.
  75
  76 inline tree
  77 gimple_range_ssa_p (tree exp)
  78 {
  79   if (exp && TREE_CODE (exp) == SSA_NAME &&
  80       !SSA_NAME_IS_VIRTUAL_OPERAND (exp) &&
  81       !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (exp) &&
  82       Value_Range::supports_type_p (TREE_TYPE (exp)))
  83     return exp;
  84   return NULL_TREE;
  85 }
  86
  87 // Return true if TYPE1 and TYPE2 are compatible range types.
  88
  89 inline bool
  90 range_compatible_p (tree type1, tree type2)
  91 {
  92   // types_compatible_p requires conversion in both directions to be useless.
  93   // GIMPLE only requires a cast one way in order to be compatible.
  94   // Ranges really only need the sign and precision to be the same.
  95   return (TYPE_PRECISION (type1) == TYPE_PRECISION (type2)
  96           && TYPE_SIGN (type1) == TYPE_SIGN (type2));
  97 }
  98
  99 // Source of all operands for fold_using_range and gori_compute.
 100 // It abstracts out the source of an operand so it can come from a stmt or
 101 // and edge or anywhere a derived class of fur_source wants.
 102 // The default simply picks up ranges from the current range_query.
 103
 104 class fur_source
 105 {
 106 public:
 107   fur_source (range_query *q = NULL);
 108   inline range_query *query () { return m_query; }
 109   inline class gori_compute *gori () { return m_gori; };
 110   virtual bool get_operand (vrange &r, tree expr);
 111   virtual bool get_phi_operand (vrange &r, tree expr, edge e);
 112   virtual relation_kind query_relation (tree op1, tree op2);
 113   virtual void register_relation (gimple *stmt, relation_kind k, tree op1,
 114                                   tree op2);
 115   virtual void register_relation (edge e, relation_kind k, tree op1,
 116                                   tree op2);
 117   void register_outgoing_edges (gcond *, irange &lhs_range, edge e0, edge e1);
 118 protected:
 119   range_query *m_query;
 120   gori_compute *m_gori;
 121 };
 122
 123 // fur_stmt is the specification for drawing an operand from range_query Q
 124 // via a range_of_Expr call on stmt S.
 125
 126 class fur_stmt : public fur_source
 127 {
 128 public:
 129   fur_stmt (gimple *s, range_query *q = NULL);
 130   virtual bool get_operand (vrange &r, tree expr) override;
 131   virtual bool get_phi_operand (vrange &r, tree expr, edge e) override;
 132   virtual relation_kind query_relation (tree op1, tree op2) override;
 133 private:
 134   gimple *m_stmt;
 135 };
 136
 137 // This version of fur_source will pick a range from a stmt, and also register
 138 // dependencies via a gori_compute object.  This is mostly an internal API.
 139
 140 class fur_depend : public fur_stmt
 141 {
 142 public:
 143   fur_depend (gimple *s, gori_compute *gori, range_query *q = NULL);
 144   virtual void register_relation (gimple *stmt, relation_kind k, tree op1,
 145                                   tree op2) override;
 146   virtual void register_relation (edge e, relation_kind k, tree op1,
 147                                   tree op2) override;
 148 protected:
 149   relation_oracle *m_oracle;
 150 };
 151
 152 // This class uses ranges to fold a gimple statement producing a range for
 153 // the LHS.  The source of all operands is supplied via the fur_source class
 154 // which provides a range_query as well as a source location and any other
 155 // required information.
 156
 157 class fold_using_range
 158 {
 159 public:
 160   bool fold_stmt (vrange &r, gimple *s, class fur_source &src,
 161                   tree name = NULL_TREE);
 162 protected:
 163   bool range_of_range_op (vrange &r, gimple_range_op_handler &handler,
 164                           fur_source &src);
 165   bool range_of_call (vrange &r, gcall *call, fur_source &src);
 166   bool range_of_cond_expr (vrange &r, gassign* cond, fur_source &src);
 167   bool range_of_address (irange &r, gimple *s, fur_source &src);
 168   bool range_of_phi (vrange &r, gphi *phi, fur_source &src);
 169   void range_of_ssa_name_with_loop_info (vrange &, tree, class loop *, gphi *,
 170                                          fur_source &src);
 171   void relation_fold_and_or (irange& lhs_range, gimple *s, fur_source &src);
 172 };
 173 #endif // GCC_GIMPLE_RANGE_FOLD_H