On 4/20/11 5:57 PM, Jerry James wrote:
On Wed, Apr 20, 2011 at 3:32 PM, Adam Jackson<ajax(a)redhat.com>
wrote:
> The least capable processor we've gone out of our way to fix things for is
> the AMD Geode GX, which has MMX and 3DNow, but is also slightly less than a
> proper Pentium Pro in that it doesn't have nopl or cmov.
>
> However, rpm sets --march=i686, which implies only Pentium Pro and does not
> imply MMX or anything newer. Not that I know of anyone who's tried running
> Fedora on a bare i686 in recent memory.
OK, that's fine. I'll compile without any of the fancy vector
instructions for i686, then explicitly pass an -march arg of my own (I
see some other packages use -march=pentium4) for the version that will
live in /usr/lib/sse2. For x86_64, I'll make sure that SSE3 and SSSE3
support is off and let it do its thing otherwise.
There do exist amd64 chips with sse3 and above. I don't know offhand
whether there's a %{_libdir}/sse3 for them, though I'd not be surprised
and I suspect a quick read of the ld.so source would tell you.
- ajax