qemu-ppc64le uncaught target signal 4 (Illegal instruction)

[Luc]

qemu-ppc64le version 2.12.0
host machine: x86_64 Arch Linux

I'm currently working on VSX support in libVPX, I'm using qemu to test, on line 723 of vpx_dsp/ppc/loopfilter_vsx.c, when I change the vec_sub to vec_subs I get:

qemu: uncaught target signal 4 (Illegal instruction) - core dumped

Thread 1 "qemu-ppc64le" received signal SIGILL, Illegal instruction.
0x00007ffff66d1bf6 in sigsuspend () from /usr/lib/libc.so.6
(gdb) bt
#0 0x00007ffff66d1bf6 in sigsuspend () from /usr/lib/libc.so.6
#1 0x000055555567ee68 in ?? ()
#2 0x000055555567fd18 in ?? ()
#3 0x00005555556805ef in process_pending_signals ()
#4 0x0000555555661e69 in cpu_loop ()
#5 0x000055555561fd72 in main ()

This can be reproduced by downloading this patch (patchset 1):

https://chromium-review.googlesource.com/c/webm/libvpx/+/1134034

and running

qemu-ppc64le -L /home/ltrudeau/x-tools/powerpc64le-unknown-linux-gnu/powerpc64le-unknown-linux-gnu/sysroot/ ./test_libvpx --gtest_also_run_disabled_tests "--gtest_filter=VSX/*Loop*/*"

I don't observe any issues when running the code on a POWER9 machine.

[Laurent Vivier (laurent-vivier)]

If it works fine on a POWER9 machine, you should try to run qemu-ppc64le with "-cpu power9".

[Luc (luctrudeau)]

Thanks for the reply.

I tried with the -cpu power9 and it works!

However, I tried with -cpu power8 and it does not work. I tried the code on a real power8 and it works. So -cpu power8 should work

[Thomas Huth (th-huth)]

The QEMU project is currently considering to move its bug tracking to
another system. For this we need to know which bugs are still valid
and which could be closed already. Thus we are setting older bugs to
"Incomplete" now.

If you still think this bug report here is valid, then please switch
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will be marked as "Expired". Or please mark it as "Fix Released" if
the problem has been solved with a newer version of QEMU already.

Thank you and sorry for the inconvenience.

[Launchpad Janitor (janitor)]

[Expired for QEMU because there has been no activity for 60 days.]