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Date: Tue, 24 Apr 2012 10:27:22 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Juri Lelli <juri.lelli@gmail.com>
Subject: Re: [RFC][PATCH 0/3] gcc work-around and math128
References: <20120424161039.293018424@chello.nl> <4F96E154.2060100@zytor.com>
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On 04/24/2012 10:22 AM, H. Peter Anvin wrote:
> On 04/24/2012 09:10 AM, Peter Zijlstra wrote:
>>
>> So far its just mult, add and cmp for u128, no divisions quite yet. I realize
>> that on 32bit archs mult_u128 will result in like 8 multiplication
>> instructions that's still nowhere near the most expensive thing ever.
>>
> 
> Please add shifts, at the very least.
> 

Oh, and a constant constructor.

	-hpa