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From: Florian Weimer <fweimer@gapps.redhat.com>
Date: Thu, 25 May 2017 21:12:00 -0000
Message-ID: <CAO3sB51R4_CyoadfLZjeV2gW7EN3MVmMudJt9B8=2bFafz53eQ@mail.gmail.com>
Subject: Re: Ping: [Patch] aarch64: Thunderx specific memcpy and memmove
To: Ramana Radhakrishnan <ramana.gcc@googlemail.com>
Cc: Siddhesh Poyarekar <siddhesh@gotplt.org>, Wilco Dijkstra <Wilco.Dijkstra@arm.com>, 
	Andrew Pinski <pinskia@gmail.com>, Szabolcs Nagy <Szabolcs.Nagy@arm.com>, 
	"Ellcey, Steve" <Steve.Ellcey@cavium.com>, libc-alpha <libc-alpha@sourceware.org>, nd <nd@arm.com>
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On Thu, May 25, 2017 at 11:04 PM, Ramana Radhakrishnan
<ramana.gcc@googlemail.com> wrote:
> The difference in the ARM world compared to the x86 world is the number
> of micro-architectures that target the same architectural baseline.
> Pushing in a memcpy
> for every single micro-architecture out there will make the library a
> maintenance nightmare !

In this case, you should reconsider putting the string functions into
the vDSO.  This will push the implementation to the kernel, but it
does more than just shifting the work: the kernel has more direct
means to provide hardware capabilities, and it also can use
just-in-time code generation (which we want to avoid in glibc).

Thanks,
Florian