gcc/tree-hash-traits.h

   1 /* Traits for hashing trees.
   2    Copyright (C) 2014-2017 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef tree_hash_traits_h
  21 #define tree_hash_traits_h
  22
  23 /* Hash for trees based on operand_equal_p.  */
  24 struct tree_operand_hash : ggc_ptr_hash <tree_node>
  25 {
  26   static inline hashval_t hash (const value_type &);
  27   static inline bool equal (const value_type &,
  28                             const compare_type &);
  29 };
  30
  31 inline hashval_t
  32 tree_operand_hash::hash (const value_type &t)
  33 {
  34   return iterative_hash_expr (t, 0);
  35 }
  36
  37 inline bool
  38 tree_operand_hash::equal (const value_type &t1,
  39                           const compare_type &t2)
  40 {
  41   return operand_equal_p (t1, t2, 0);
  42 }
  43
  44 /* Hasher for tree decls.  Pointer equality is enough here, but the DECL_UID
  45    is a better hash than the pointer value and gives a predictable traversal
  46    order.  */
  47 struct tree_decl_hash : ggc_ptr_hash <tree_node>
  48 {
  49   static inline hashval_t hash (tree);
  50 };
  51
  52 inline hashval_t
  53 tree_decl_hash::hash (tree t)
  54 {
  55   return DECL_UID (t);
  56 }
  57
  58 /* Hash for SSA_NAMEs in the same function.  Pointer equality is enough
  59    here, but the SSA_NAME_VERSION is a better hash than the pointer
  60    value and gives a predictable traversal order.  */
  61 struct tree_ssa_name_hash : ggc_ptr_hash <tree_node>
  62 {
  63   static inline hashval_t hash (tree);
  64 };
  65
  66 inline hashval_t
  67 tree_ssa_name_hash::hash (tree t)
  68 {
  69   return SSA_NAME_VERSION (t);
  70 }
  71
  72 /* Hasher for general trees, based on their TREE_HASH.  */
  73 struct tree_hash : ggc_ptr_hash <tree_node>
  74 {
  75   static hashval_t hash (tree);
  76 };
  77
  78 inline hashval_t
  79 tree_hash::hash (tree t)
  80 {
  81   return TREE_HASH (t);
  82 }
  83
  84 #endif