This is the mail archive of the
mailing list for the glibc project.
Re: [PATCH] Define HAS_CPUID/HAS_I586/HAS_I686 from -march=
- From: "H.J. Lu" <hjl dot tools at gmail dot com>
- To: OndÅej BÃlka <neleai at seznam dot cz>
- Cc: GNU C Library <libc-alpha at sourceware dot org>
- Date: Tue, 18 Aug 2015 06:34:25 -0700
- 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> <20150818052442 dot GA26531 at domone>
On Mon, Aug 17, 2015 at 10:24 PM, OndÅej BÃlka <email@example.com> wrote:
> 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?
I will use HAS_I586 and HAS_I686 in multi-arch for i486 and i586
I am working on.