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Lu" Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Mon, Apr 22, 2024 at 4:42=E2=80=AFPM Jan Beulich wro= te: > > On 22.04.2024 09:47, Hongtao Liu wrote: > > On Mon, Apr 22, 2024 at 3:44=E2=80=AFPM Cui, Lili = wrote: > >>> On 22.04.2024 06:09, Hongtao Liu wrote: > >>>> On Fri, Apr 19, 2024 at 5:29=E2=80=AFPM Jan Beulich wrote: > >>>>> > >>>>> Since we uniformly permit D suffixes in Intel mode whenever in AT&T > >>>>> mode an L suffix may be used, we need to be consistent with this. > >>>> I think we need to forbid the D suffix for APX NDD SHL/SHR under Int= el > >>>> mode to avoid ambiguity. > >>> > >>> Hmm. Special casing just two insns is out of question imo (in fact th= at's what > >>> is - unintentionally - partly happening prior to the change here). > >>> > > I know the suffix L is needed in AT&T mode to specify the operand > > size to avoid ambiguity. > > But why do we need the suffix D for Intel mode? > > We don't need it. But that's not just here; the vast majority of insns sh= ould > never have permitted suffixes in Intel syntax. Yet here we are. And the > question is what to do about it. What I've been considering in the meanti= me > is to disallow suffixes where not needed by default, but have a command l= ine > option to restore original behavior (perhaps right away with a deprecatio= n > warning), just to allow people to get their (bogus) code to build again (= or, > if need be, to work around issues we might introduce, i.e. mistakenly > refusing use of a suffix where one might in fact be needed). Thoughts? I prefer to issue a deprecation warning and drop the support in some future release. Easy maintenance. > > Jan --=20 BR, Hongtao