Revert of [turbofan][arm64] Match fneg for -0.0 - x pattern.

src/compiler/arm64/instruction-selector-arm64.cc

 // 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.
 
 #include "src/compiler/instruction-selector-impl.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 1051 matching lines @@
 
 
 void InstructionSelector::VisitFloat64Add(Node* node) {
   VisitRRRFloat64(this, kArm64Float64Add, node);
 }
 
 
 void InstructionSelector::VisitFloat64Sub(Node* node) {
   Arm64OperandGenerator g(this);
   Float64BinopMatcher m(node);
-  if (m.left().IsMinusZero()) {
-    if (m.right().IsFloat64RoundDown() &&
-        CanCover(m.node(), m.right().node())) {
-      if (m.right().InputAt(0)->opcode() == IrOpcode::kFloat64Sub &&
-          CanCover(m.right().node(), m.right().InputAt(0))) {
-        Float64BinopMatcher mright0(m.right().InputAt(0));
-        if (mright0.left().IsMinusZero()) {
-          Emit(kArm64Float64RoundUp, g.DefineAsRegister(node),
-               g.UseRegister(mright0.right().node()));
-          return;
-        }
+  if (m.left().IsMinusZero() && m.right().IsFloat64RoundDown() &&
+      CanCover(m.node(), m.right().node())) {
+    if (m.right().InputAt(0)->opcode() == IrOpcode::kFloat64Sub &&
+        CanCover(m.right().node(), m.right().InputAt(0))) {
+      Float64BinopMatcher mright0(m.right().InputAt(0));
+      if (mright0.left().IsMinusZero()) {
+        Emit(kArm64Float64RoundUp, g.DefineAsRegister(node),
+             g.UseRegister(mright0.right().node()));
+        return;
       }
     }
-    Emit(kArm64Float64Neg, g.DefineAsRegister(node),
-         g.UseRegister(m.right().node()));
-    return;
   }
   VisitRRRFloat64(this, kArm64Float64Sub, node);
 }
 
 
 void InstructionSelector::VisitFloat64Mul(Node* node) {
   VisitRRRFloat64(this, kArm64Float64Mul, node);
 }
 
 
@@ skipping 566 matching lines @@
          MachineOperatorBuilder::kFloat64Max |
          MachineOperatorBuilder::kFloat64Min |
          MachineOperatorBuilder::kWord32ShiftIsSafe |
          MachineOperatorBuilder::kInt32DivIsSafe |
          MachineOperatorBuilder::kUint32DivIsSafe;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8