[intrinsics] Kill the %_IsMinusZero intrinsic.

src/full-codegen/mips64/full-codegen-mips64.cc

Index: src/full-codegen/mips64/full-codegen-mips64.cc
diff --git a/src/full-codegen/mips64/full-codegen-mips64.cc b/src/full-codegen/mips64/full-codegen-mips64.cc
index bbe9f7ffe4ceea6e6136a816b8fd4a4eda34ea0c..9e2caf1fea0eef5c367b174661b26cb9b45e1764 100644
--- a/src/full-codegen/mips64/full-codegen-mips64.cc
+++ b/src/full-codegen/mips64/full-codegen-mips64.cc
@@ -3020,36 +3020,6 @@ void FullCodeGenerator::EmitIsSimdValue(CallRuntime* expr) {
 }
 
 
-void FullCodeGenerator::EmitIsMinusZero(CallRuntime* expr) {
-  ZoneList<Expression*>* args = expr->arguments();
-  DCHECK(args->length() == 1);
-
-  VisitForAccumulatorValue(args->at(0));
-
-  Label materialize_true, materialize_false;
-  Label* if_true = NULL;
-  Label* if_false = NULL;
-  Label* fall_through = NULL;
-  context()->PrepareTest(&materialize_true, &materialize_false,
-                         &if_true, &if_false, &fall_through);
-
-  __ CheckMap(v0, a1, Heap::kHeapNumberMapRootIndex, if_false, DO_SMI_CHECK);
-  __ lwu(a2, FieldMemOperand(v0, HeapNumber::kExponentOffset));
-  __ lwu(a1, FieldMemOperand(v0, HeapNumber::kMantissaOffset));
-  __ li(a4, 0x80000000);
-  Label not_nan;
-  __ Branch(&not_nan, ne, a2, Operand(a4));
-  __ mov(a4, zero_reg);
-  __ mov(a2, a1);
-  __ bind(&not_nan);
-
-  PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
-  Split(eq, a2, Operand(a4), if_true, if_false, fall_through);
-
-  context()->Plug(if_true, if_false);
-}
-
-
 void FullCodeGenerator::EmitIsArray(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 1);