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Re: Rebuilding RPMs results in bad update behavior



On Tue, 2007-06-12 at 23:41 -0400, Dave Jones wrote:
> No surprise really.
> generic isn't targetting either of the processors you mention.
> The idea behind generic is 'optimise for _todays_ CPUs', which
> right now typically means Intel Core, and AMD Opteron/Athlon64.
> On these platforms, cmov isn't a win (and is even a loss in
> some cases).

I thought Core is a revival of the PIII core. At any rate, "generic" is
an -mtune option only, so alone it will not use cmovs anyway because
they're not supported earlier that i686.

I just tried it, gcc compiling for i386 uses cmov for a signed divide by
128 with march = i686, pentiumpro, pentium2, pentium3, pentium4, core2
and k8. Compiling for x86_64, it uses cmov on march = generic, k8 and
core2.

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