Re: [OpenRISC] [PATCH v3 09/25] openrisc: add optimized atomic operations

[Richard Henderson]

On 02/23/2017 01:22 AM, Stafford Horne wrote:
> > static inline int __atomic_add_unless(atomic_t *v, int a, int u)
> > {
> > 	int old, tmp;
> >
> > 	__asm__ __volatile__(
> > 		"1:     l.lwa %0, 0(%2)         \n"
> > 		"       l.sfeq %0, %4           \n"
> > 		"       l.bf 2f                 \n"
> > 		"        l.nop                  \n"
> > 		"	l.add %1, %0, %3	\n"

You can move this add into the delay slot and drop the preceding nop.


r~