[intrinsics] Kill the %_IsMinusZero intrinsic.

src/compiler/js-intrinsic-lowering.cc

Index: src/compiler/js-intrinsic-lowering.cc
diff --git a/src/compiler/js-intrinsic-lowering.cc b/src/compiler/js-intrinsic-lowering.cc
index ef0b0ff04217a90df9fe08f83db7a02ce611ab5a..e0b772d1f2a295f72e536fcf4bf0af337e20449c 100644
--- a/src/compiler/js-intrinsic-lowering.cc
+++ b/src/compiler/js-intrinsic-lowering.cc
@@ -69,8 +69,6 @@ Reduction JSIntrinsicLowering::Reduce(Node* node) {
       return ReduceMathSqrt(node);
     case Runtime::kInlineValueOf:
       return ReduceValueOf(node);
-    case Runtime::kInlineIsMinusZero:
-      return ReduceIsMinusZero(node);
     case Runtime::kInlineFixedArrayGet:
       return ReduceFixedArrayGet(node);
     case Runtime::kInlineFixedArraySet:
@@ -338,30 +336,6 @@ Reduction JSIntrinsicLowering::Change(Node* node, const Operator* op) {
 }
 
 
-Reduction JSIntrinsicLowering::ReduceIsMinusZero(Node* node) {
-  Node* value = NodeProperties::GetValueInput(node, 0);
-  Node* effect = NodeProperties::GetEffectInput(node);
-
-  Node* double_lo =
-      graph()->NewNode(machine()->Float64ExtractLowWord32(), value);
-  Node* check1 = graph()->NewNode(machine()->Word32Equal(), double_lo,
-                                  jsgraph()->ZeroConstant());
-
-  Node* double_hi =
-      graph()->NewNode(machine()->Float64ExtractHighWord32(), value);
-  Node* check2 = graph()->NewNode(
-      machine()->Word32Equal(), double_hi,
-      jsgraph()->Int32Constant(static_cast<int32_t>(0x80000000)));
-
-  ReplaceWithValue(node, node, effect);
-
-  Node* and_result = graph()->NewNode(machine()->Word32And(), check1, check2);
-
-  return Change(node, machine()->Word32Equal(), and_result,
-                jsgraph()->Int32Constant(1));
-}
-
-
 Reduction JSIntrinsicLowering::ReduceFixedArrayGet(Node* node) {
   Node* base = node->InputAt(0);
   Node* index = node->InputAt(1);