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From: Florian Weimer <fw@deneb.enyo.de>
To: "H.J. Lu via Libc-alpha" <libc-alpha@sourceware.org>
Cc: Noah Goldstein <goldstein.w.n@gmail.com>,  GCC Development
 <gcc@gcc.gnu.org>,  "H.J. Lu" <hjl.tools@gmail.com>,  Arjan van de Ven
 <arjan@linux.intel.com>
Subject: Re: [PATCH] x86-64: Optimize memset for zeroing
References: <20211231182010.107040-1-hjl.tools@gmail.com>
 <CAFUsyfJ5wHJHkfcL84j+GLCX-Dba4qVt_RuCpu=aLy7-_YbHLA@mail.gmail.com>
 <CAMe9rOq0cW28i-_DeLfdxD3HDRTXy17ie9ZC1NxsqfRLjBz4Yw@mail.gmail.com>
Date: Fri, 31 Dec 2021 21:43:22 +0100
In-Reply-To: <CAMe9rOq0cW28i-_DeLfdxD3HDRTXy17ie9ZC1NxsqfRLjBz4Yw@mail.gmail.com>
 (H. J. Lu via Libc-alpha's message of "Fri, 31 Dec 2021 12:35:44
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* H. J. Lu via Libc-alpha:

> bzero is an alias of SSE2 memset in glibc.   Should we add __memsetzero
> like __memcmpeq?  It should be almost free in glibc.  GCC can use
> __memsetzero if it is available.

bzero does not have the interface ambiguity that bcmp has.  So the
only reason for not using it would be namespace cleanliness.