[intrinsics] Kill the %_IsMinusZero intrinsic.

src/crankshaft/x87/lithium-codegen-x87.cc

Index: src/crankshaft/x87/lithium-codegen-x87.cc
diff --git a/src/crankshaft/x87/lithium-codegen-x87.cc b/src/crankshaft/x87/lithium-codegen-x87.cc
index 3d81843abbedfd6c9b1cfe9fe754606f996b94d0..8c10d119a5c76b936595f24163c7a902ee8b1a58 100644
--- a/src/crankshaft/x87/lithium-codegen-x87.cc
+++ b/src/crankshaft/x87/lithium-codegen-x87.cc
@@ -2505,29 +2505,6 @@ void LCodeGen::DoCmpHoleAndBranch(LCmpHoleAndBranch* instr) {
 }
 
 
-void LCodeGen::DoCompareMinusZeroAndBranch(LCompareMinusZeroAndBranch* instr) {
-  Representation rep = instr->hydrogen()->value()->representation();
-  DCHECK(!rep.IsInteger32());
-
-  if (rep.IsDouble()) {
-    X87Register input = ToX87Register(instr->value());
-    X87LoadForUsage(input);
-    __ FXamMinusZero();
-    EmitBranch(instr, equal);
-  } else {
-    Register value = ToRegister(instr->value());
-    Handle<Map> map = masm()->isolate()->factory()->heap_number_map();
-    __ CheckMap(value, map, instr->FalseLabel(chunk()), DO_SMI_CHECK);
-    __ cmp(FieldOperand(value, HeapNumber::kExponentOffset),
-           Immediate(0x1));
-    EmitFalseBranch(instr, no_overflow);
-    __ cmp(FieldOperand(value, HeapNumber::kMantissaOffset),
-           Immediate(0x00000000));
-    EmitBranch(instr, equal);
-  }
-}
-
-
 Condition LCodeGen::EmitIsString(Register input,
                                  Register temp1,
                                  Label* is_not_string,