[Bug inline-asm/11819] rejects-valid: GCC inline assembler rejects valid MMX constraints

bkausbk at web dot de gcc-bugzilla@gcc.gnu.org
Wed Aug 6 14:08:00 GMT 2003


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11819



------- Additional Comments From bkausbk at web dot de  2003-08-06 14:08 -------
But as far as I understand constraints, it should also be possible to use "=y" 
constraint.
With "+y" compiler also keep the original value that was stored in "a" before 
asm() call. But this isn't needed sometimes. Like it is possible for general 
purpose registers it should also be possible for MMX registers. Correct code 
for "=y" should be:

	movq	-16(%ebp), %mm1
/APP
.intel_syntax noprefix
       pxor %mm0, %mm0
       paddb %mm0, %mm1
/NO_APP
	movq	%mm0, -8(%ebp)



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