Revert of [x86] Use better left operand heuristic for Float64Add and...

Revert of [x86] Use better left operand heuristic for Float64Add and Float64Mul. (patchset #1 id:1 of https://codereview.chromium.org/958583003/)

Reason for revert:
Tanks on Atom and Haswell

Original issue's description:
> [x86] Use better left operand heuristic for Float64Add and Float64Mul.
>
> R=dcarney@chromium.org
>
> Committed: https://crrev.com/9da259fb1f4ecfefeb2cf7efbe449d8aa1904032
> Cr-Commit-Position: refs/heads/master@{#26849}

TBR=dcarney@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/972243002

Cr-Commit-Position: refs/heads/master@{#26973}

src/compiler/ia32/instruction-selector-ia32.cc

@@ -634,15 +634,12 @@ void InstructionSelector::VisitTruncateFloat64ToFloat32(Node* node) {
 
 void InstructionSelector::VisitFloat64Add(Node* node) {
   IA32OperandGenerator g(this);
-  Node* left = node->InputAt(0);
-  Node* right = node->InputAt(1);
-  if (g.CanBeBetterLeftOperand(right)) std::swap(left, right);
   if (IsSupported(AVX)) {
-    Emit(kAVXFloat64Add, g.DefineAsRegister(node), g.UseRegister(left),
-         g.Use(right));
+    Emit(kAVXFloat64Add, g.DefineAsRegister(node),
+         g.UseRegister(node->InputAt(0)), g.Use(node->InputAt(1)));
   } else {
-    Emit(kSSEFloat64Add, g.DefineSameAsFirst(node), g.UseRegister(left),
-         g.Use(right));
+    Emit(kSSEFloat64Add, g.DefineSameAsFirst(node),
+         g.UseRegister(node->InputAt(0)), g.Use(node->InputAt(1)));
   }
 }
 
@@ -661,15 +658,12 @@ void InstructionSelector::VisitFloat64Sub(Node* node) {
 
 void InstructionSelector::VisitFloat64Mul(Node* node) {
   IA32OperandGenerator g(this);
-  Node* left = node->InputAt(0);
-  Node* right = node->InputAt(1);
-  if (g.CanBeBetterLeftOperand(right)) std::swap(left, right);
   if (IsSupported(AVX)) {
-    Emit(kAVXFloat64Mul, g.DefineAsRegister(node), g.UseRegister(left),
-         g.Use(right));
+    Emit(kAVXFloat64Mul, g.DefineAsRegister(node),
+         g.UseRegister(node->InputAt(0)), g.Use(node->InputAt(1)));
   } else {
-    Emit(kSSEFloat64Mul, g.DefineSameAsFirst(node), g.UseRegister(left),
-         g.Use(right));
+    Emit(kSSEFloat64Mul, g.DefineSameAsFirst(node),
+         g.UseRegister(node->InputAt(0)), g.Use(node->InputAt(1)));
   }
 }
 

src/compiler/x64/instruction-selector-x64.cc

@@ -832,15 +832,12 @@ void InstructionSelector::VisitTruncateInt64ToInt32(Node* node) {
 
 void InstructionSelector::VisitFloat64Add(Node* node) {
   X64OperandGenerator g(this);
-  Node* left = node->InputAt(0);
-  Node* right = node->InputAt(1);
-  if (g.CanBeBetterLeftOperand(right)) std::swap(left, right);
   if (IsSupported(AVX)) {
-    Emit(kAVXFloat64Add, g.DefineAsRegister(node), g.UseRegister(left),
-         g.Use(right));
+    Emit(kAVXFloat64Add, g.DefineAsRegister(node),
+         g.UseRegister(node->InputAt(0)), g.Use(node->InputAt(1)));
   } else {
-    Emit(kSSEFloat64Add, g.DefineSameAsFirst(node), g.UseRegister(left),
-         g.Use(right));
+    Emit(kSSEFloat64Add, g.DefineSameAsFirst(node),
+         g.UseRegister(node->InputAt(0)), g.Use(node->InputAt(1)));
   }
 }
 
@@ -859,15 +856,12 @@ void InstructionSelector::VisitFloat64Sub(Node* node) {
 
 void InstructionSelector::VisitFloat64Mul(Node* node) {
   X64OperandGenerator g(this);
-  Node* left = node->InputAt(0);
-  Node* right = node->InputAt(1);
-  if (g.CanBeBetterLeftOperand(right)) std::swap(left, right);
   if (IsSupported(AVX)) {
-    Emit(kAVXFloat64Mul, g.DefineAsRegister(node), g.UseRegister(left),
-         g.Use(right));
+    Emit(kAVXFloat64Mul, g.DefineAsRegister(node),
+         g.UseRegister(node->InputAt(0)), g.Use(node->InputAt(1)));
   } else {
-    Emit(kSSEFloat64Mul, g.DefineSameAsFirst(node), g.UseRegister(left),
-         g.Use(right));
+    Emit(kSSEFloat64Mul, g.DefineSameAsFirst(node),
+         g.UseRegister(node->InputAt(0)), g.Use(node->InputAt(1)));
   }
 }