[Valgrind-users] Need test case for: REPE then 0xF: Unhandled REPE case

[Julian S. <js...@ac...>]

Hello.  I'm trying to put together bug fixes for 1.9.6.

Several people reported this panic:

   REPE then 0xF

   valgrind: the `impossible' happened:
      Unhandled REPE case

I'd like to fix it, since it seems to afflict quite a number
of people.  However, reading my Intel P4 documentation I can't
figure out what instruction this is.

So: does anyone have a smallish test case I can use to reproduce
this with?  Or (not so good, but it would be a help) can anyone
tell me what the byte after the 0xF is?  You can find out
by changing vg_to_ucode.c:4321 from

         VG_(printf)("REPE then 0x%x\n", (UInt)abyte);

to

         VG_(printf)("REPE then 0x%x 0x%x\n", (UInt)abyte,
                                              (UInt)getUChar(eip));

I prefer a test case tho, so I can test any fix I make.

Thanks,

J