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Re: reload vs adds with clobbers
On Fri, 2003-06-06 at 05:17, DJ Delorie wrote:
> Unfortunately, all the const_int constraints are used up in that port.
> Does GCC play nice when you use an arbitrary constraint letter for
> const_ints?
No. Reload needs to know that it is a constant constraint letter so
that it can call CONST_OK_FOR_LETTER_P. There is EXTRA_CONSTRAINT that
might work. You can use any letter that isn't used elsewhere in
EXTRA_CONSTRAINT. You have to be careful not to use anything that has a
predefined meaning. Generally capitol letters are safer than lower
case.
You can also use strings as constraint "letters" now, but I don't see
any port using this feature, so it seems risky to try to use it.
Jim