MMX & Floating point insn suport for reversible debugging

Hui Zhu teawater@gmail.com
Thu May 14 07:11:00 GMT 2009


On Thu, May 14, 2009 at 00:44, paawan oza <paawan1982@yahoo.com> wrote:
>
> I have gone through i387-tdep.c.
> and I have come up with following doubts.
>
>  here I start adding floating point register support.
>  I think curerntly it records the memory
>
>  so remaining thing for floating point is store
>  registers st0 to st7.
>
>
>> > code to be added here...
>> >   /* floats */
>> >      /* It just record the memory change of
>> instrcution. */
>> >    case 0xd8:
>> >    case 0xd9:
>> >    case 0xda:
>> >    case 0xdb:
>> >    case 0xdc:
>> >    case 0xdd:
>> >    case 0xde:
>> >    case 0xdf:
>> >
>> >
>    do we need to collect affect FPU flags !!

If gdb can output and set this flags, you need to do it.
And I suggest you post more clear information about your question that
you know when you have question with it.  It will make people reply
you mail easyly, right?  :)

>
>    and another thing is ;
>    take floating point insn
>    opcode  mnemnic   desc
>    DE F9   FDIVP     Divide ST(1) by ST(0),
>                      store result in ST(1), and
>                      pop the register stack.
>
> I do not think code is taking care of 2 bytes floating
> instruction..
> I suspoe ModR/M and SIB byte encoding is taken care
> with respect to floating point.

Why you can't put the code for "DE F9" in:
>> >    case 0xde:


Thanks,
Hui



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