[turbofan] Add support for change/truncate to MachineOperatorReducer.

src/compiler/machine-operator-reducer.h

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_COMPILER_MACHINE_OPERATOR_REDUCER_H_
 #define V8_COMPILER_MACHINE_OPERATOR_REDUCER_H_
 
 #include "src/compiler/common-operator.h"
 #include "src/compiler/graph-reducer.h"
 #include "src/compiler/machine-operator.h"
@@ skipping 14 matching lines @@
   MachineOperatorReducer(Graph* graph, CommonNodeCache* cache);
 
   virtual Reduction Reduce(Node* node);
 
  private:
   Graph* graph_;
   CommonNodeCache* cache_;
   CommonOperatorBuilder common_;
   MachineOperatorBuilder machine_;
 
+  Node* Float64Constant(volatile double value);
   Node* Int32Constant(int32_t value);
-  Node* Float64Constant(volatile double value);
+  Node* Int64Constant(int64_t value);
 
   Reduction ReplaceBool(bool value) { return ReplaceInt32(value ? 1 : 0); }
-
+  Reduction ReplaceFloat64(volatile double value) {
+    return Replace(Float64Constant(value));
+  }
   Reduction ReplaceInt32(int32_t value) {
     return Replace(Int32Constant(value));
   }
-
-  Reduction ReplaceFloat64(volatile double value) {
-    return Replace(Float64Constant(value));
+  Reduction ReplaceInt64(int64_t value) {
+    return Replace(Int64Constant(value));
   }
 };
 }
 }
 }  // namespace v8::internal::compiler
 
 #endif  // V8_COMPILER_MACHINE_OPERATOR_REDUCER_H_