On Mon, 2006-06-05 at 12:47, Wolfgang Mües wrote:
> > /* Output the address of an operand. */
> > #define ARM_PRINT_OPERAND_ADDRESS(STREAM, X) \
> > { \
> > int is_minus = GET_CODE (X) == MINUS;
> > \
> > \
> > if (GET_CODE (X) == REG)
> > \
> > asm_fprintf (STREAM, "[%r]", REGNO (X));
> > \
>
> I don't know why the form "[%r, #0]" was coded before, because the
> assembler understands "[%r]" very well for all instructions. The form
> "[%r]" has a wider usage because it covers swp too.
Historical reasons. In the past gas would incorrectly assemble '[rn]'
as '[rn], #0' which was unpredictable if rn appeared in the load/store
target. However, this bug was fixed several years ago now, so it's
probably safe to switch back to the short form.
R.
