Re: [PATCH v2] x86: ignore high register select bit(s) in 32- and 16-bit modes

["Jan Beulich" <JBeulich at suse dot com>]

>>> On 16.11.17 at 11:53, <hjl.tools@gmail.com> wrote:
> On Wed, Nov 15, 2017 at 7:47 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
>> On Tue, Nov 14, 2017 at 11:57 PM, Jan Beulich <JBeulich@suse.com> wrote:
>>> While commits 9889cbb14e ("Check invalid mask registers") and
>>> abfcb414b9 ("X86: Ignore REX_B bit for 32-bit XOP instructions") went a
>>> bit into the right direction, this wasn't quite enough:
>>> - VEX.vvvv has its high bit ignored
>>> - EVEX.vvvv has its high bit ignored together with EVEX.v'
>>> - the high bits of {,E}VEX.vvvv should not be prematurely zapped, to
>>>   allow proper checking of them when the fields has to hold al ones
>>> - when the high bits of an immediate specify a register, bit 7 is
>>>   ignored
>>> ---
>>> v2: Parts of the test were moved to earlier, already approved (and
>>>     committed) patches.
>>>
>>> gas/
>>> 2017-11-15  Jan Beulich  <jbeulich@suse.com>
>>>
>>>         * testsuite/gas/i386/noextreg.s: Add tests with register index
>>>         bit 3 set.
>>>         * testsuite/gas/i386/noextreg.d: Adjust expectations.
>>>
>>
>> The new test fails on i386 when binutils is configured with:
>>
>> --enable-plugins --disable-gdb --disable-sim --disable-readline
>> --disable-libdecnumber --enable-compressed-debug-sections=gas,ld
>> i686-linux \
>> \
>> --prefix=/usr/local \
>> --with-local-prefix=/usr/local
>>
>> since .code64 isn't supported:
>>
>> Executing on host: sh -c {../as-new  --32  -o dump.o
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s
>> 2>&1}  /dev/null gas.out (timeout = 300)
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:
>> Assembler messages:
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:5:
>> Error: unknown pseudo-op: `.code64'
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:6:
>> Error: too many memory references for `andn'
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:10:
>> Error: unknown pseudo-op: `.code64'
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:11:
>> Error: too many memory references for `tzmsk'
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:15:
>> Error: unknown pseudo-op: `.code64'
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:16:
>> Error: operand size mismatch for `llwpcb'
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:
>> Assembler messages:
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:5:
>> Error: unknown pseudo-op: `.code64'
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:6:
>> Error: too many memory references for `andn'
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:10:
>> Error: unknown pseudo-op: `.code64'
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:11:
>> Error: too many memory references for `tzmsk'
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:15:
>> Error: unknown pseudo-op: `.code64'
>> 
> /export/gnu/import/git/sources/binutils-gdb/gas/testsuite/gas/i386/noextreg.s:16:
>> Error: operand size mismatch for `llwpcb'
>>
>> Please fix it.
> 
> This is what I checked in.

Thanks, but using .byte is what I wanted to specifically avoid as far
as possible. I'd much rather exclude the test for 64-bit incapable
assemblers. But you're the maintainer ...

Jan