On 9 January 2015 at 11:24, Paolo Bonzini <pbonz...@redhat.com> wrote: > On 09/01/2015 12:04, Frediano Ziglio wrote: >> I think that I'll write two patches. One implementing using the int128 >> as you suggested (which is much easier to read that current one and >> assembly ones) that another for x86_64 optimization. > > Right, that's even better.
Personally I would prefer we didn't write inline assembly functions if we can avoid them. So I'd rather see an int128 version, and if the compiler doesn't do a good enough job then go talk to the compiler folks to improve things. > Out of curiosity, have you seen it in some profiles? I would absolutely want to see significant perf uplift on a real workload before we start putting inline asm into qemu-common.h... -- PMM