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

Jan Beulich jbeulich@suse.com
Fri Feb 14 13:54:00 GMT 2020 
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?

Jan
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