[turbofan] fold constants in compares

src/compiler/machine-operator-reducer.h

Index: src/compiler/machine-operator-reducer.h
diff --git a/src/compiler/machine-operator-reducer.h b/src/compiler/machine-operator-reducer.h
index 475ed2ecdd9db413d5f41642aebd5edc3f1d27c2..0f6651a92ea8aff12475e9801d956ce33e1a46ae 100644
--- a/src/compiler/machine-operator-reducer.h
+++ b/src/compiler/machine-operator-reducer.h
@@ -61,6 +61,14 @@ class MachineOperatorReducer FINAL : public Reducer {
     return Replace(Int64Constant(value));
   }
 
+  Reduction ReduceWord32Equal(Node* node);
+  Reduction ReduceWord64Equal(Node* node);
+  Reduction ReduceInt32LessThan(Node* node);
+  Reduction ReduceInt32LessThanOrEqual(Node* node);
+  Reduction ReduceUint32LessThan(Node* node);
+  Reduction ReduceUint32LessThanOrEqual(Node* node);
+  Reduction ReduceCompare32(Node* node);
+
   Reduction ReduceInt32Div(Node* node);
   Reduction ReduceUint32Div(Node* node);
   Reduction ReduceInt32Mod(Node* node);