EarlyCSE: fix CmpPredicate duplicate-hashing

Fixes #119893.

Author: artagnon

llvm/include/llvm/IR/CmpPredicate.h

@@ -71,13 +71,7 @@ class CmpPredicate {
 
   /// Get the swapped predicate of a CmpInst.
   static CmpPredicate getSwapped(const CmpInst *Cmp);
-
-  /// Provided to facilitate storing a CmpPredicate in data structures that
-  /// require hashing.
-  friend hash_code hash_value(const CmpPredicate &Arg); // NOLINT
 };
-
-[[nodiscard]] hash_code hash_value(const CmpPredicate &Arg);
 } // namespace llvm
 
 #endif

llvm/lib/IR/Instructions.cpp

@@ -3946,10 +3946,6 @@ CmpPredicate CmpPredicate::getSwapped(const CmpInst *Cmp) {
   return getSwapped(get(Cmp));
 }
 
-hash_code llvm::hash_value(const CmpPredicate &Arg) { // NOLINT
-  return hash_combine(Arg.Pred, Arg.HasSameSign);
-}
-
 //===----------------------------------------------------------------------===//
 //                        SwitchInst Implementation
 //===----------------------------------------------------------------------===//

llvm/lib/Transforms/Scalar/EarlyCSE.cpp

@@ -290,7 +290,8 @@ static unsigned getHashValueImpl(SimpleValue Val) {
       Pred = CmpInst::getInversePredicate(Pred);
       std::swap(A, B);
     }
-    return hash_combine(Inst->getOpcode(), Pred, X, Y, A, B);
+    return hash_combine(Inst->getOpcode(),
+                        static_cast<CmpInst::Predicate>(Pred), X, Y, A, B);
   }
 
   if (CastInst *CI = dyn_cast<CastInst>(Inst))