Re: [PATCH 10/10] x86: correct VFPCLASSP{S,D} operand size handling

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Tue, Aug 6, 2019 at 7:29 AM Jan Beulich <jbeulich@suse.com> wrote:
>
> With AVX512VL disabled (e.g. when writing code for the Knights family
> of processors) these insns aren't ambiguous when used with a memory
> source, and hence should be accepted without suffix or operand size
> specifier. When AVX512VL is enabled, to be consistent with this as
> well as other ambiguous operand size handling it seems better to just
> wanrn about the ambiguity in AT&T mode, and still default to 512-bit
> operands (on the assumption that the code may have been written without
> AVX512VL in mind yet).
>
> gas/
> 2019-08-XX  Jan Beulich  <jbeulich@suse.com>
>
>         * config/tc-i386.c (avx512): New (at file scope), moved from
>         (check_VecOperands): ... here.
>         (process_suffix): Add [XYZ]MMword operand size handling.
>         * testsuite/gas/i386/noavx512-2.s, testsuite/gas/i386/noreg16.s,
>         testsuite/gas/i386/noreg32.s, testsuite/gas/i386/noreg64.s: Add
>         VFPCLASS tests.
>         * testsuite/gas/i386/noavx512-2.l, testsuite/gas/i386/noreg16.d,
>         testsuite/gas/i386/noreg16.l, testsuite/gas/i386/noreg32.d,
>         testsuite/gas/i386/noreg32.l, testsuite/gas/i386/noreg64.d,
>         testsuite/gas/i386/noreg64.l: Adjust expectations.
>
> opcodes/
> 2019-08-XX  Jan Beulich  <jbeulich@suse.com>
>
>         * i386-opc.tbl (vfpclasspd, vfpclassps): Add Unspecified.
>         * i386-tbl.h: Re-generate.
>

We should keep the suffix even if AVX512VL isn't enabled so that
we don't need to check if AVX512VL isn't enabled to interpret the
instruction.

-- 
H.J.