On Wednesday 08 March 2006 21:45, "Richard Fish" <[EMAIL PROTECTED]> wrote about 'Re: [gentoo-user] equery, make.conf USE flag mismatch on amd64': > On 3/8/06, Kumar Golap <[EMAIL PROTECTED]> wrote: > > Thanks all for your help...and I know why now mmx flag was getting > > masked. Its in the use.mask as suggested by Martins. > > The mmx USE flag is not supported on the amd64 profile. The processor > does support mmx instructions, but (I think) only when operating in > 32-bit mode.
I know it supports them, and I'm fairly sure the work in 64-bit mode. > So it probably doesn't make sense to have an amd64 > profile with the mmx/sse/3dnow use flags. Presumably there are better > processor instructions for a true 64-bit multi-media application to > use... Actually, since ALL x86_64 processors support these instructions, it's kinda silly to compile without using these instruction sets. There are few, if any, extended instruction sets for x86_64, AFAIK, so mmx3/sse2 is probably the fastest code path for multimedia operations. -- "If there's one thing we've established over the years, it's that the vast majority of our users don't have the slightest clue what's best for them in terms of package stability." -- Gentoo Developer Ciaran McCreesh -- gentoo-user@gentoo.org mailing list
