Unify hash functions for pairs (#1161)

CVC4 was implementing multiple, slightly different hash functions for
pairs. With pull request #1157, we have a decent generic hash function
for pairs. This commit replaces the existing hash function
implementations with a typedef of the generic hash function.

1 files changed, 9 insertions, 9 deletions

diff --git a/src/theory/uf/equality_engine_types.h b/src/theory/uf/equality_engine_types.h
index ed0afa904..b3b8ac7d6 100644
--- a/src/theory/uf/equality_engine_types.h
+++ b/src/theory/uf/equality_engine_types.h
@@ -17,10 +17,15 @@
 
 #include "cvc4_private.h"
 
+#ifndef __CVC4__THEORY__UF__EQUALITY_ENGINE_TYPES_H
+#define __CVC4__THEORY__UF__EQUALITY_ENGINE_TYPES_H
+
 #include <string>
 #include <iostream>
 #include <sstream>
 
+#include "util/hash.h"
+
 namespace CVC4 {
 namespace theory {
 namespace eq {
@@ -264,15 +269,8 @@ public:
 
 /** A pair of ids */
 typedef std::pair<EqualityNodeId, EqualityNodeId> EqualityPair;
-
-struct EqualityPairHashFunction {
-  size_t operator () (const EqualityPair& pair) const {
-    size_t hash = 0;
-    hash = 0x9e3779b9 + pair.first;
-    hash ^= 0x9e3779b9 + pair.second + (hash << 6) + (hash >> 2);
-    return hash;
-  }
-};
+using EqualityPairHashFunction =
+    PairHashFunction<EqualityNodeId, EqualityNodeId>;
 
 enum FunctionApplicationType {
   /** This application is an equality a = b */
@@ -362,3 +360,5 @@ struct TriggerInfo {
 } // namespace eq
 } // namespace theory
 } // namespace CVC4
+
+#endif /* __CVC4__THEORY__UF__EQUALITY_ENGINE_TYPES_H */