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Re: [PATCH] Define HAS_CPUID/HAS_I586/HAS_I686 from -march=
- From: OndÅej BÃlka <neleai at seznam dot cz>
- To: "H.J. Lu" <hjl dot tools at gmail dot com>
- Cc: GNU C Library <libc-alpha at sourceware dot org>
- Date: Tue, 18 Aug 2015 07:24:42 +0200
- Subject: Re: [PATCH] Define HAS_CPUID/HAS_I586/HAS_I686 from -march=
- Authentication-results: sourceware.org; auth=none
- References: <20150817231005 dot GA24205 at intel dot com>
On Mon, Aug 17, 2015 at 04:10:05PM -0700, H.J. Lu wrote:
> cpuid, i586 and i686 instructions are available if the processor
> specified by -march= supports them. We can use this information
> to determine whether those instructions can be used safely.
>
> OK for master?
>
Patch itself looks ok. It fixes theoretical problem that if there would
be new processor without cpuid it would cause problem.
But could you explain rationale? Here you replaced one like with
equivalent longer macro and HAS_I586 is never used. Do you plan followup
patches that use that?