This is the mail archive of the
mailing list for the glibc project.
Re: [PATCH][AArch64] Optimized memcpy/memmove
- From: Marcus Shawcroft <marcus dot shawcroft at gmail dot com>
- To: Wilco Dijkstra <Wilco dot Dijkstra at arm dot com>
- Cc: GNU C Library <libc-alpha at sourceware dot org>, nd <nd at arm dot com>
- Date: Thu, 12 May 2016 16:39:59 +0100
- Subject: Re: [PATCH][AArch64] Optimized memcpy/memmove
- Authentication-results: sourceware.org; auth=none
- References: <AM3PR08MB00884C9733FDD45E7E75974783EE0 at AM3PR08MB0088 dot eurprd08 dot prod dot outlook dot com>
On 15 December 2015 at 16:40, Wilco Dijkstra <Wilco.Dijkstra@arm.com> wrote:
> -----Original Message-----
> From: Wilco Dijkstra [mailto:email@example.com]
> Sent: 25 September 2015 14:17
> To: 'GNU C Library'
> Subject: [PATCH][AArch64] Optimized memcpy/memmove
> Further optimize memcpy/memmove for AArch64. Copies are split into 3 main cases: small copies of up to 16 bytes, medium copies of 17..96 bytes which are fully unrolled. Large copies of more than 96 bytes align the destination and use an unrolled loop processing 64 bytes per iteration. In order to share code with memmove, small and medium copies read all data before writing, allowing any kind of overlap. All memmoves except for the large backwards case fall into memcpy for optimal performance. On a random copy test memcpy/memmove are 40% faster on A57 and 28% on A53.
> OK for commit?
> 2015-09-25 Wilco Dijkstra <firstname.lastname@example.org>
> * sysdeps/aarch64/memcpy.S (memcpy):
> Rewrite of optimized memcpy and memmove.
> * sysdeps/aarch64/memmove.S (memmove): Remove
> memmove code (merged into memcpy.S).
Hi, There appear to be odd tab characters inserted throughout the
comments, for example:
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ boundaries on both loads and stores. There are at least 96 bytes
+ to copy, so copy 16 bytes unaligned and then align. The loop
Please fix, (and check for other instances) and post a the respin.