On Wed, Apr 26, 2017 at 01:44:43PM -0700, Ricardo Neri wrote:
> I regard that the role of this function is to obtain the the segment
> selector from either of the prefixes or inferred from the operands. It
> is the role of caller to determine if the segment selector should be
> ignored.

No, this is wrong. The function is called resolve_seg_selector() and it
gives you the segment selector. CS, DS, ES, and SS in 64-bit mode are
treated as null segments and your function should return/signal exactly
that, i.e, saying that those should be ignored in that case.

> I double-checked the latest version of the Intel Software Development
> manual [2], in the table 3-5 in section 3.7.4 mentions that DS is
> default segment for all data references, except string destinations. I
> tested this code with the UMIP-protected instructions and whenever I use
> %edi the default segment is %ds.

Yes, all correct. Except that we're adding a more-or-less generic x86
insn decoder so we should make it so...

> Is this example valid? The documentation of MOVS specifies that it
> always moves DS:(E)SI to ES:(E)DI.

... that the decoder should do exactly that:

        if (MOVS and rDI)
                return SEG_ES;

And you're handing in struct insn * so you can easily check which insn
you're looking at.

Thanks.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imend├Ârffer, Jane Smithard, Graham Norton, HRB 21284 
(AG N├╝rnberg)
-- 
--
To unsubscribe from this list: send the line "unsubscribe linux-msdos" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to