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Re: valgrind support for glibc/kernel arm64 HWCAPS
- From: Florian Weimer <fweimer at redhat dot com>
- To: Siddhesh Poyarekar <siddhesh at gotplt dot org>, Mark Wielaard <mark at klomp dot org>
- Cc: GNU C Library <libc-alpha at sourceware dot org>, valgrind-developers at lists dot sourceforge dot net
- Date: Wed, 5 Jul 2017 21:04:15 +0200
- Subject: Re: valgrind support for glibc/kernel arm64 HWCAPS
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On 07/05/2017 08:56 PM, Siddhesh Poyarekar wrote:
> On Wednesday 05 July 2017 09:12 PM, Mark Wielaard wrote:
>> I am not sure I understand this part.
>> What are micro-architecture specific routines?
>
> These are routines written specifically for vendor CPUs, such as the
> thunderx version of memcpy and memmove. The HWCAP_CPUID allows for such
> routines to be launched on the correct hardware, but when run under
> valgrind, those routines will not get called and any potential bugs in
> those routines may get masked.
Why do you expect valgrind to be able to execute code specific to vendor
CPUs? That's not even true for i386 and x86-64 and micro-architecture
ISA extensions.
Thanks,
Florian