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, range_query *q = NULL);
  41 bool fold_range (vrange &r, gimple *s, vrange &r1, vrange &r2,
  42                  range_query *q = NULL);
  43 bool fold_range (vrange &r, gimple *s, unsigned num_elements, vrange **vector,
  44                  range_query *q = NULL);
  45
  46 // This routine will return a relation trio for stmt S.
  47 relation_trio fold_relations (gimple *s, range_query *q = NULL);
  48
  49 // Return the type of range which statement S calculates.  If the type is
  50 // unsupported or no type can be determined, return NULL_TREE.
  51
  52 inline tree
  53 gimple_range_type (const gimple *s)
  54 {
  55   tree lhs = gimple_get_lhs (s);
  56   tree type = NULL_TREE;
  57   if (lhs)
  58     type = TREE_TYPE (lhs);
  59   else
  60     {
  61       enum gimple_code code = gimple_code (s);
  62       if (code == GIMPLE_COND)
  63         type = boolean_type_node;
  64       else if (code == GIMPLE_PHI)
  65         type = TREE_TYPE (gimple_phi_result (s));
  66       else if (code == GIMPLE_CALL)
  67         {
  68           type = gimple_call_fntype (s);
  69           // If it has a type, get the return type.
  70           if (type)
  71             type = TREE_TYPE (type);
  72         }
  73     }
  74   if (type && Value_Range::supports_type_p (type))
  75     return type;
  76   return NULL_TREE;
  77 }
  78
  79 // Return EXP if it is an SSA_NAME with a type supported by gimple ranges.
  80
  81 inline tree
  82 gimple_range_ssa_p (tree exp)
  83 {
  84   if (exp && TREE_CODE (exp) == SSA_NAME &&
  85       !SSA_NAME_IS_VIRTUAL_OPERAND (exp) &&
  86       !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (exp) &&
  87       Value_Range::supports_type_p (TREE_TYPE (exp)))
  88     return exp;
  89   return NULL_TREE;
  90 }
  91
  92 // Return true if TYPE1 and TYPE2 are compatible range types.
  93
  94 inline bool
  95 range_compatible_p (tree type1, tree type2)
  96 {
  97   // types_compatible_p requires conversion in both directions to be useless.
  98   // GIMPLE only requires a cast one way in order to be compatible.
  99   // Ranges really only need the sign and precision to be the same.
 100   return (TYPE_PRECISION (type1) == TYPE_PRECISION (type2)
 101           && TYPE_SIGN (type1) == TYPE_SIGN (type2));
 102 }
 103
 104 // Source of all operands for fold_using_range and gori_compute.
 105 // It abstracts out the source of an operand so it can come from a stmt or
 106 // and edge or anywhere a derived class of fur_source wants.
 107 // The default simply picks up ranges from the current range_query.
 108
 109 class fur_source
 110 {
 111 public:
 112   fur_source (range_query *q = NULL);
 113   inline range_query *query () { return m_query; }
 114   inline class gori_compute *gori () { return m_gori; };
 115   virtual bool get_operand (vrange &r, tree expr);
 116   virtual bool get_phi_operand (vrange &r, tree expr, edge e);
 117   virtual relation_kind query_relation (tree op1, tree op2);
 118   virtual void register_relation (gimple *stmt, relation_kind k, tree op1,
 119                                   tree op2);
 120   virtual void register_relation (edge e, relation_kind k, tree op1,
 121                                   tree op2);
 122   void register_outgoing_edges (gcond *, irange &lhs_range, edge e0, edge e1);
 123 protected:
 124   range_query *m_query;
 125   gori_compute *m_gori;
 126 };
 127
 128 // fur_stmt is the specification for drawing an operand from range_query Q
 129 // via a range_of_Expr call on stmt S.
 130
 131 class fur_stmt : public fur_source
 132 {
 133 public:
 134   fur_stmt (gimple *s, range_query *q = NULL);
 135   virtual bool get_operand (vrange &r, tree expr) override;
 136   virtual bool get_phi_operand (vrange &r, tree expr, edge e) override;
 137   virtual relation_kind query_relation (tree op1, tree op2) override;
 138 private:
 139   gimple *m_stmt;
 140 };
 141
 142 // This version of fur_source will pick a range from a stmt, and also register
 143 // dependencies via a gori_compute object.  This is mostly an internal API.
 144
 145 class fur_depend : public fur_stmt
 146 {
 147 public:
 148   fur_depend (gimple *s, gori_compute *gori, range_query *q = NULL);
 149   virtual void register_relation (gimple *stmt, relation_kind k, tree op1,
 150                                   tree op2) override;
 151   virtual void register_relation (edge e, relation_kind k, tree op1,
 152                                   tree op2) override;
 153 protected:
 154   relation_oracle *m_oracle;
 155 };
 156
 157 // This class uses ranges to fold a gimple statement producing a range for
 158 // the LHS.  The source of all operands is supplied via the fur_source class
 159 // which provides a range_query as well as a source location and any other
 160 // required information.
 161
 162 class fold_using_range
 163 {
 164 public:
 165   bool fold_stmt (vrange &r, gimple *s, class fur_source &src,
 166                   tree name = NULL_TREE);
 167 protected:
 168   bool range_of_range_op (vrange &r, gimple_range_op_handler &handler,
 169                           fur_source &src);
 170   bool range_of_call (vrange &r, gcall *call, fur_source &src);
 171   bool range_of_cond_expr (vrange &r, gassign* cond, fur_source &src);
 172   bool range_of_address (irange &r, gimple *s, fur_source &src);
 173   bool range_of_phi (vrange &r, gphi *phi, fur_source &src);
 174   void range_of_ssa_name_with_loop_info (vrange &, tree, class loop *, gphi *,
 175                                          fur_source &src);
 176   void relation_fold_and_or (irange& lhs_range, gimple *s, fur_source &src);
 177 };
 178 #endif // GCC_GIMPLE_RANGE_FOLD_H