Re: LC040 FPU emulation

[Meelis Roos <mroos@linux.ee>]

>> A wild idea: if the appropriate exception is not generated, why do I get an
>> 'Illegal instruction' exception? If I catch all the other exceptions and check
>> whether there was a FPU instruction before the problem, would it help?

One more data point: sometimes it gives SIGILL, sometimes SIGSEGV, and usually
SIGBUS. This all from the same binary with the same arguments.

>>         - Insertion of a NOP before the FPU instruction solves the
>>           problem.

JaW> Now, _this_ is interesting! Couldn't the program loader be patched to
JaW> insert a NOP before any and all FPU instruction?

I doubt it would be easy enough. Inserting a command would shift all the
following commands so code offsets would change.

-- 
Meelis Roos (mroos@linux.ee)