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Re: ENTER/BOUND operands order.

>>> On 23.01.14 at 12:05, "Michael V. Zolotukhin" <> wrote:
>>  I don't think EVEX.W determines the scaling factor here. The
>> input consists of dword elements, hence the scaling ought to
>> be 4. I think the manual even states so (but I didn't re-check).
> No, it's EVEX.W who defines scaling in this case.  The manual says that
> VPMULU?DQ has FV (full vector) in 'operand encoding' column, and the table 
> 4-6
> gives the scaling factors for different operand encoding depending on 
> broadcasting, and vector length.  For the given instruction is yields 8.

But then again it says

VPMULDQ zmm1 {k1}{z}, zmm2, zmm3/m512/m32bcst
VPMULUDQ zmm1 {k1}{z}, zmm2, zmm3/m512/m32bcst

Using 8-byte granular scaling with 4-byte broadcast operands
would make little sense.

The table you refer to also says 64bit in the Input column, which
clearly is wrong for these two instructions. Hence I consider this
table inapplicable here, and an explicit note about the scaling
factor would then be desirable.


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