Selectively disable optimization on macro?

I have a macro:

#define EnterCritical()
  do {     SP++;     *(unsigned char idata *)(SP-1) = IE;     EA = 0;   } while (0);

that I call multiple times (along with its complement, ExitCritical()) in a particular function. With C51's optimization level set at 9, the optimizer is turning these in-line macros into a function and calling them -- this obviously won't work, due to the operations on SP.

Is there a way for me to maintain the OPTIMIZE(9,SIZE) settings for the module but ensure that the macro is left in its original in-line state whenever I invoke it?

Thanks,