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From: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>
To: Wainer dos Santos Moschetta <wainersm@linux.vnet.ibm.com>
Cc: <libc-alpha@sourceware.org>
Subject: Re: [PATCH] powerpc64: Add POWER8 strnlen
Date: Thu, 23 Mar 2017 21:15:00 -0000	[thread overview]
Message-ID: <955A086F-92D5-420A-A063-9D5FBA6F2D18@linux.vnet.ibm.com> (raw)
In-Reply-To: <20170321201144.10513-1-wainersm@linux.vnet.ibm.com>



On 3/21/17, 5:11 PM, "Wainer dos Santos Moschetta" <libc-alpha-owner@sourceware.org on behalf of wainersm@linux.vnet.ibm.com> wrote:

    Added strnlen POWER8 otimized for long strings. It delivers
    same performance as POWER7 implementation for short strings.
    
    This takes advantage of reasonably performing unaligned loads
    and bit permutes to check the first 1-16 bytes until
    quadword aligned, then checks in 64 bytes strides until unsafe,
    then 16 bytes, truncating the count if need be.
    
    Likewise, the POWER7 code is recycled for less than 32 bytes strings.
    
    Tested on ppc64 and ppc64le.
    


LGTM


--
Carlos Eduardo Seo
Software Engineer - Linux on Power Toolchain
cseo@linux.vnet.ibm.com
 
 


  reply	other threads:[~2017-03-23 21:15 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-21 20:11 Wainer dos Santos Moschetta
2017-03-23 21:15 ` Carlos Eduardo Seo [this message]
2017-03-31 20:55   ` Wainer dos Santos Moschetta
2017-04-05 14:51     ` Tulio Magno Quites Machado Filho

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