[turbofan] Transform x * -1.0 to -0.0 - x.

test/unittests/compiler/node-test-utils.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_UNITTESTS_COMPILER_NODE_TEST_UTILS_H_
 #define V8_UNITTESTS_COMPILER_NODE_TEST_UTILS_H_
 
 #include "src/compiler/machine-operator.h"
 #include "src/compiler/machine-type.h"
 #include "testing/gmock/include/gmock/gmock.h"
@@ skipping 138 matching lines @@
                                        const Matcher<Node*>& rhs_matcher);
 Matcher<Node*> IsChangeFloat64ToInt32(const Matcher<Node*>& input_matcher);
 Matcher<Node*> IsChangeFloat64ToUint32(const Matcher<Node*>& input_matcher);
 Matcher<Node*> IsChangeInt32ToFloat64(const Matcher<Node*>& input_matcher);
 Matcher<Node*> IsChangeInt32ToInt64(const Matcher<Node*>& input_matcher);
 Matcher<Node*> IsChangeUint32ToFloat64(const Matcher<Node*>& input_matcher);
 Matcher<Node*> IsChangeUint32ToUint64(const Matcher<Node*>& input_matcher);
 Matcher<Node*> IsTruncateFloat64ToFloat32(const Matcher<Node*>& input_matcher);
 Matcher<Node*> IsTruncateFloat64ToInt32(const Matcher<Node*>& input_matcher);
 Matcher<Node*> IsTruncateInt64ToInt32(const Matcher<Node*>& input_matcher);
+Matcher<Node*> IsFloat64Sub(const Matcher<Node*>& lhs_matcher,
+                            const Matcher<Node*>& rhs_matcher);
 Matcher<Node*> IsFloat64Sqrt(const Matcher<Node*>& input_matcher);
 Matcher<Node*> IsFloat64Floor(const Matcher<Node*>& input_matcher);
 Matcher<Node*> IsFloat64Ceil(const Matcher<Node*>& input_matcher);
 Matcher<Node*> IsFloat64RoundTruncate(const Matcher<Node*>& input_matcher);
 Matcher<Node*> IsFloat64RoundTiesAway(const Matcher<Node*>& input_matcher);
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_UNITTESTS_COMPILER_NODE_TEST_UTILS_H_