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Re: [PATCH] aarch64: Optimized implementation of memrchr
- From: Wilco Dijkstra <Wilco dot Dijkstra at arm dot com>
- To: Xuelei Zhang <zhangxuelei4 at huawei dot com>, "libc-alpha at sourceware dot org" <libc-alpha at sourceware dot org>, "siddhesh at gotplt dot org" <siddhesh at gotplt dot org>, Szabolcs Nagy <Szabolcs dot Nagy at arm dot com>, "jiangyikun at huawei dot com" <jiangyikun at huawei dot com>, "yikunkero at gmail dot com" <yikunkero at gmail dot com>
- Cc: nd <nd at arm dot com>
- Date: Tue, 22 Oct 2019 17:01:33 +0000
- Subject: Re: [PATCH] aarch64: Optimized implementation of memrchr
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- References: <20191017145155.14076-1-zhangxuelei4@huawei.com>
Hi Xuelei,
> Considering the excellent performance of memchr.S on glibc 2.30, the
> same algorithm is used to find chrin. Compared to memrchr.c, this
> method with memrchr.S achieves an average performance improvement
> of 58% based on benchtest and its extension cases.
For larger sizes it's more than 4 times faster than the generic version. The
implementation is very similar to memchr.S so this is OK.
Wilco