On Thu, May 26, 2011 at 09:10:32AM -0700, Andi Kleen wrote: > Richard Guenther <richard.guent...@gmail.com> writes: > As for why having a builtin: one reason would be portability.
You mean portability to other compilers (I think reasonable amount of them support gcc-ish inline asm), or to other architectures? __builtin_ia32_pause () doesn't look like a builtin you would want to use on PPC. > Then it also seems cleaner to me to cover the instruction > set with builtins like the others. No idea why in this case. Builtins have the advantage that they can be better scheduled, but in this case you don't want to move it around. Jakub