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Date: Wed, 15 May 2019 14:47:00 -0000
From: Michael Matz <matz@suse.de>
To: Jakub Jelinek <jakub@redhat.com>
cc: Aaron Sawdey <acsawdey@linux.ibm.com>,     Richard Biener <richard.guenther@gmail.com>,     GCC Development <gcc@gcc.gnu.org>, Joseph Myers <joseph@codesourcery.com>,     Jeff Law <law@redhat.com>, Segher Boessenkool <segher@kernel.crashing.org>,     David Edelsohn <dje.gcc@gmail.com>, Bill Schmidt <wschmidt@linux.ibm.com>
Subject: Re: Fixing inline expansion of overlapping memmove and non-overlapping memcpy
In-Reply-To: <20190515141106.GK19695@tucnak>
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Hi,

On Wed, 15 May 2019, Jakub Jelinek wrote:

> Just one thing to note, our "memcpy" expectation is that either there is 
> no overlap, or there is 100% overlap (src == dest), both all the current 
> movmem == future cpymem expanders and all the supported library 
> implementations do support that, though the latter just de-facto, it 
> isn't a written guarantee.

Yes, I should have been more precise, complete overlap is always de-facto 
supported as well.


Ciao,
Michael.