[PATCH v8 2/2] x86/AT&T: don't default to byte source for ambiguous for MOVSX/MOVZX

[H.J. Lu]

On Fri, Feb 14, 2020 at 5:54 AM Jan Beulich <jbeulich@suse.com> wrote:
>
> On 14.02.2020 13:28, H.J. Lu wrote:
> > On Fri, Feb 14, 2020 at 4:26 AM Jan Beulich <jbeulich@suse.com> wrote:
> >>
> >> As pointed out in "x86: replace adhoc (partly wrong) ambiguous operand
> >> checking for MOVSX/MOVZX" silently guessing what the programmer may have
> >> meant is not helpful, the more that we don't do so elsewhere anymore
> >> (except in cases where it is overwhelmingly likely that the other case
> >> isn't meant, like here for it meant to be a "sign/zero extension" from
> >> 16 bits to 16 bits).
> >>
> >> gas/
> >> 2020-02-XX  Jan Beulich  <jbeulich@suse.com>
> >>
> >>         PR gas/25438
> >>         * config/tc-i386.c (process_suffix): Default movsx/movzx to byte
> >>         suffix only when destination is a word reg.
> >>         testsuite/gas/i386/noreg16.l, testsuite/gas/i386/noreg32.l,
> >>         testsuite/gas/i386/noreg64.l: Adjust expectations.
> >
> > No need for this since this is documented behavior of AT&T syntax.
>
> I've just looked at the documentation again: As said in the
> other reply to your doc change, these mnemonics aren't
> mentioned as legal in Solaris'es AT&T spec. And I also
> can't find gas doc saying so. Would you please point me at
> where this is being documented?

Solaris spec doesn't mention movsx[bwl] nor movsx.


-- 
H.J.