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Subject: Re: [RFC PATCH] x86/hweight: Get rid of the special calling
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To: Borislav Petkov <bp@suse.de>
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Cc: Brian Gerst <brgerst@gmail.com>, LKML <linux-kernel@vger.kernel.org>,
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From: "H. Peter Anvin" <hpa@zytor.com>
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Date: Wed, 4 May 2016 13:51:14 -0700
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On 05/04/2016 01:22 PM, Borislav Petkov wrote:
> On Wed, May 04, 2016 at 12:49:17PM -0700, H. Peter Anvin wrote:
>> Sigh.  Doesn't look like -Wa is going to help due to the lack of the
>> equivalent of an -include option in gas.
> 
> So much for the register "freedom" - I'll resurrect the hardcoded insn
> bytes. :-\
> 
> Unless my gcc friends have some other ideas...

There is the option of looking for assembler support for popcnt and only
hard-code the register if not supported.  This is where being able to
insert a macro package would help...

	-hpa