Re: RFC: [2.6 patch] better i386 CPU selection

Dave Jones
2003-09-11T11:06:41Z

On Thu, Sep 11, 2003 at 08:28:16AM +0200, Adrian Bunk wrote:

> - Does the Cyrix III support 686 instructions?

Depends on your definition of 686. If you follow the Intel
definition (where CMOV is optional), yes. If you follow the gcc
definition (where CMOV is assumed), no.
Except for the latest Nehemiah cores (which now have CMOV).

> - Do -march=winchip{2,-c6} and -march=c3{,-2} add anything not in
> -march=i686 (except optimizations of otherwise compatible code)?

Not afaik.

> - Which CPUs exactly need X86_ALIGNMENT_16?

Unsure. This could use testing on a few systems.

> - X86_GOOD_APIC: Are there really that many processors with a bad APIC?

Mikael ?

Dave

--
Dave Jones http://www.codemonkey.org.uk