Re: PATCH: Move operand/address-size override prefixes before SIMD prefix

["H. J. Lu" <hjl at lucon dot org>]

On Wed, Dec 06, 2006 at 12:07:42PM +1030, Alan Modra wrote:
> On Tue, Dec 05, 2006 at 04:04:32PM -0800, H. J. Lu wrote:
> > On Wed, Dec 06, 2006 at 10:20:04AM +1030, Alan Modra wrote:
> > > Please add a comment as to why this is desirable.
> >     WAIT_PREFIX must be the first prefix since FWAIT is really is an
> > -   instruction, and so must come before any prefixes.  */
> > +   instruction, and so must come before any prefixes.
> > +   ADDR_PREFIX and DATA_PREFIX are preferred before LOCKREP_PREFIX.  */
> 
> Really?  My old copy of the Intel instruction set reference says:
> "For each instruction, one prefix may be used from each of these
> groups and be placed in any order."

Any order will work. But the preferred order is ADDR_PREFIX,
DATA_PREFIX, LOCKREP_PREFIX due to SIMD.


H.J.