[Valgrind-developers] vex amd64->IR: unhandled instruction bytes: 0x48 0x8C 0xDB 0x48

[Konstantin S. <kon...@gm...>]

Hi,
While trying to run one of my tests under helgrind (unmodified valgrind
3.3.0 on x86_64) I've got the following message:

vex amd64->IR: unhandled instruction bytes: 0x48 0x8C 0xDB 0x48
==25817== valgrind: Unrecognised instruction at address 0x22CA8185.
==25817== Your program just tried to execute an instruction that Valgrind
==25817== did not recognise.  There are two possible reasons for this.
==25817== 1. Your program has a bug and erroneously jumped to a non-code
==25817==    location.  If you are running Memcheck and you just saw a
==25817==    warning about a bad jump, it's probably your program's fault.
==25817== 2. The instruction is legitimate but Valgrind doesn't handle it,
==25817==    i.e. it's Valgrind's fault.  If you think this is the case or
==25817==    you are not sure, please let us know and we'll try to fix it.
==25817== Either way, Valgrind will now raise a SIGILL signal which will
==25817== probably kill your program.


Surprisingly, it only happens under helgrind, memcheck works fine.
I am not sure if this is 'Your program has a bug and erroneously jumped to a
non-code' or 'The instruction is legitimate but Valgrind doesn't handle it'.

Is there anything I could do to figure this out?


--kcc