Subject: Re: [PATCH 2/5] bitops: compile time optimization for
 hweight_long(CONSTANT)
From: Peter Zijlstra <peterz@infradead.org>
To: Borislav Petkov <petkovbb@googlemail.com>
Cc: Borislav Petkov <bp@amd64.org>, "H. Peter Anvin" <hpa@zytor.com>,
       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>
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Date: Sun, 14 Feb 2010 13:23:35 +0100
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On Sun, 2010-02-14 at 12:24 +0100, Borislav Petkov wrote:
> 
> So, if I understand you correctly, your suggestion might work, we
> simply need to rename the lib/hweight.c versions to __sw_hweightN
> and have <asm-generic/bitops/arch_hweight.h> have __arch_hweightN ->
> __sw_hweightN wrappers in the default case, all arches which have an
> optimized version will provide it in their respective bitops header...
> 
I'm not quite sure what the last 'it' refers to, does that refer to:
 1) an __arch_hweightN() implementation, or
 2) __arch_hweightN() -> __sw_hweightN() wrappers ?

If you meant 1, then yes.

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