Re: [RFC PATCH 0/4] improve coverage of vector backend

[Alex Bennée]

Taylor Simpson <tsimpson@quicinc.com> writes:

>> -----Original Message-----
>> From: Alex Bennée <alex.bennee@linaro.org>
>> Sent: Thursday, February 3, 2022 11:50 AM
>> To: Taylor Simpson <tsimpson@quicinc.com>
>> Cc: richard.henderson@linaro.org; qemu-devel@nongnu.org; qemu-
>> arm@nongnu.org; fam@euphon.net; berrange@redhat.com;
>> f4bug@amsat.org; aurelien@aurel32.net; pbonzini@redhat.com;
>> stefanha@redhat.com; crosa@redhat.com
>> Subject: Re: [RFC PATCH 0/4] improve coverage of vector backend
>> 
>> Taylor Simpson <tsimpson@quicinc.com> writes:
>> 
>> > Quick update - I ran the test on the hardware and have the same error
>> messages.
>> >
>> > So, it doesn't look like a QEMU problem.  I'll investigate if the
>> > problem is due to something in the toolchain.
>> 
>> That reminds me what is the status of the binary toolchain. The last attempt
>> had some issues so we are still using the hand-built one upstream.
>
> No progress on that.  The team hasn't had the bandwidth to work on it.
>
> However, I'm less suspicious of the toolchain now. I built with a
> couple of different compiler options and a couple of different
> versions of the toolchain, including the C library that runs in
> production. In all cases, I see the same result.
>
> Any chance the problem is in the test itself (e.g., some sort of
> undefined behavior or a 64-bit vs 32-bit difference)?

It does have a 64 bit byteswap in - it's possible I broke it copying
from the upstream:

  https://ccodearchive.net/info/crypto/sha512.html

but it does pass on *all* the other architectures which is a mix of 32
and 64 bit code. I did have to hack the endian detection code though.
Does:

  #if BYTE_ORDER == BIG_ENDIAN

work for your compiler?


>
> Thanks,
> Taylor


-- 
Alex Bennée