tree-hash-traits.h (tree_ssa_name_hasher): New class.

gcc/
	* tree-hash-traits.h (tree_ssa_name_hasher): New class.
	* sese.c: Include tree-hash-traits.h.
	(rename_map_hasher): Use tree_ssa_name_hasher.

From-SVN: r224969

gcc/ChangeLog

 2015-06-25  Richard Sandiford  <richard.sandiford@arm.com>
 
+	* tree-hash-traits.h (tree_ssa_name_hasher): New class.
+	* sese.c: Include tree-hash-traits.h.
+	(rename_map_hasher): Use tree_ssa_name_hasher.
+
+2015-06-25  Richard Sandiford  <richard.sandiford@arm.com>
+
 	* tree-hash-traits.h (tree_decl_hash): New class.
 	* tree-ssa-strlen.c: Include tree-hash-traits.h.
 	(stridxlist_hash_traits): Use tree_decl_hash.

gcc/sese.c

@@ -60,6 +60,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "value-prof.h"
 #include "sese.h"
 #include "tree-ssa-propagate.h"
+#include "tree-hash-traits.h"
 
 /* Helper function for debug_rename_map.  */
 
@@ -75,22 +76,7 @@ debug_rename_map_1 (tree_node *const &old_name, tree_node *const &expr,
   return true;
 }
 
-
-/* Hashtable helpers.  */
-
-struct rename_map_hasher : default_hashmap_traits
-{
-  static inline hashval_t hash (tree);
-};
-
-/* Computes a hash function for database element ELT.  */
-
-inline hashval_t
-rename_map_hasher::hash (tree old_name)
-{
-  return SSA_NAME_VERSION (old_name);
-}
-
+typedef simple_hashmap_traits<tree_ssa_name_hash> rename_map_hasher;
 typedef hash_map<tree, tree, rename_map_hasher> rename_map_type;
 
 

gcc/tree-hash-traits.h

@@ -53,4 +53,18 @@ tree_decl_hash::hash (tree t)
   return DECL_UID (t);
 }
 
+/* Hash for SSA_NAMEs in the same function.  Pointer equality is enough
+   here, but the SSA_NAME_VERSION is a better hash than the pointer
+   value and gives a predictable traversal order.  */
+struct tree_ssa_name_hash : ggc_ptr_hash <tree_node>
+{
+  static inline hashval_t hash (tree);
+};
+
+inline hashval_t
+tree_ssa_name_hash::hash (tree t)
+{
+  return SSA_NAME_VERSION (t);
+}
+
 #endif