Changed GeneratePow ensure xmm1 is loaded with y before making the test for NaN

Review URL: http://codereview.chromium.org/660172

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3966 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/ia32/codegen-ia32.cc

@@ -5368,13 +5368,12 @@ void CodeGenerator::GeneratePow(ZoneList<Expression*>* args) {
       __ cmp(FieldOperand(y.reg(), HeapObject::kMapOffset),
              Factory::heap_number_map());
       __ j(not_equal, &go_runtime);
+      // Y must be a double.
+      __ movdbl(xmm1, FieldOperand(y.reg(), HeapNumber::kValueOffset));
       // Test if y is nan.
       __ ucomisd(xmm1, xmm1);
       __ j(parity_even, &go_runtime);
 
-      // Y must be a double.
-      __ movdbl(xmm1, FieldOperand(y.reg(), HeapNumber::kValueOffset));
-
       Label x_not_smi;
       Label handle_special_cases;
       __ test(x.reg(), Immediate(kSmiTagMask));