Fix number tag for no-sse2.

src/ia32/lithium-codegen-ia32.cc

Index: src/ia32/lithium-codegen-ia32.cc
diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index 9a49e16312942f1963adb8c7cac30a4f97f44569..46d0c1f46faaef5b8cbdf286a258fc05f2182dcb 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -5070,6 +5070,7 @@ void LCodeGen::DoNumberTagD(LNumberTagD* instr) {
       __ ucomisd(input_reg, input_reg);
     } else {
       __ fld(0);
+      __ fld(0);
       __ FCmp();
     }
 
@@ -5116,16 +5117,12 @@ void LCodeGen::DoNumberTagD(LNumberTagD* instr) {
     __ jmp(deferred->entry());
   }
   __ bind(deferred->exit());
-  if (CpuFeatures::IsSupported(SSE2)) {
+  if (use_sse2) {
     CpuFeatureScope scope(masm(), SSE2);
     XMMRegister input_reg = ToDoubleRegister(instr->value());
     __ movdbl(FieldOperand(reg, HeapNumber::kValueOffset), input_reg);
   } else {
-    __ fst_d(FieldOperand(reg, HeapNumber::kValueOffset));
-  }
-  if (!use_sse2) {
-    // clean up the stack
-    __ fstp(0);
+    __ fstp_d(FieldOperand(reg, HeapNumber::kValueOffset));
   }
   __ bind(&done);
 }