Avoid pushing arguments twice in GenericBinaryOpStub....

src/ia32/code-stubs-ia32.cc

Index: src/ia32/code-stubs-ia32.cc
===================================================================
--- src/ia32/code-stubs-ia32.cc	(revision 5415)
+++ src/ia32/code-stubs-ia32.cc	(working copy)
@@ -1044,12 +1044,13 @@
       StringAddStub string_add_left_stub(NO_STRING_CHECK_LEFT_IN_STUB);
       __ TailCallStub(&string_add_left_stub);
 
+      Label call_runtime_with_args;
       // Left operand is not a string, test right.
       __ bind(&lhs_not_string);
       __ test(rhs, Immediate(kSmiTagMask));
-      __ j(zero, &call_runtime);
+      __ j(zero, &call_runtime_with_args);
       __ CmpObjectType(rhs, FIRST_NONSTRING_TYPE, ecx);
-      __ j(above_equal, &call_runtime);
+      __ j(above_equal, &call_runtime_with_args);
 
       StringAddStub string_add_right_stub(NO_STRING_CHECK_RIGHT_IN_STUB);
       __ TailCallStub(&string_add_right_stub);
@@ -1059,6 +1060,7 @@
       if (HasArgsInRegisters()) {
         GenerateRegisterArgsPush(masm);
       }
+      __ bind(&call_runtime_with_args);
       __ InvokeBuiltin(Builtins::ADD, JUMP_FUNCTION);
       break;
     }