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Date: Tue, 10 May 2016 21:10:42 +0200
From: Borislav Petkov <bp@suse.de>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>, x86-ml <x86@kernel.org>,
        Denys Vlasenko <dvlasenk@redhat.com>, Brian Gerst <brgerst@gmail.com>,
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        Andy Lutomirski <luto@amacapital.net>
Subject: Re: [PATCH -v2] x86/hweight: Get rid of the special calling
 convention
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On Tue, May 10, 2016 at 12:03:48PM -0700, H. Peter Anvin wrote:
> Also, to be fair... if the problem is with these being in C then we
> could just do it in assembly easily enough.

I thought about converting the __sw_hweight* variants to asm but
__sw_hweight32, for example, is 55 bytes here and that's a lot.

Or do you have a better idea?

peterz's sounds ok to me: we call a thunk which then calls __sw_hweight*
after having saved regs properly - problem solved.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--