From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH] x86: Add optimized popcnt variants
Date: Tue, 23 Feb 2010 09:34:04 -0800
Message-ID: <4B84118C.90203@zytor.com>
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Cc: Michal Marek <mmarek@suse.cz>,
	linux-kbuild <linux-kbuild@vger.kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Wu Fengguang <fengguang.wu@intel.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Jamie Lokier <jamie@shareable.org>,
	Roland Dreier <rdreier@cisco.com>,
	Al Viro <viro@ZenIV.linux.org.uk>,
	"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
	Ingo Molnar <mingo@elte.hu>, Brian Gerst <brgerst@gmail.com>
To: Borislav Petkov <bp@amd64.org>
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On 02/23/2010 07:58 AM, Borislav Petkov wrote:
>
> Hmm, we cannot do that with the current design since __arch_hweight64
> is being inlined into every callsite and AFAICT we would have to build
> every callsite with "-fcall-saved-rdi" which is clearly too much. The
> explicit "=D" dummy constraint is straightforward, instead.
>

Uh... the -fcall-saved-rdi would go with all the other ones.  Assuming 
it can actually work and that gcc doesn't choke on an inbound argument 
being saved.

	-hpa