[PATCH] Support APX zero-upper

[Cui, Lili]

> On 09.05.2024 09:56, Cui, Lili wrote:
> >> On 28.04.2024 12:54, Cui, Lili wrote:
> >>> @@ -528,6 +530,7 @@ loopne, 0xe0, x64,
> >>> JumpByte|No_bSuf|No_wSuf|No_sSuf|NoRex64, { Disp8 }
> >>>
> >>>  // Set byte on flag instructions.
> >>>  set<cc>, 0xf9<cc:opc>/0, i386,
> >> Modrm|No_wSuf|No_lSuf|No_sSuf|No_qSuf,
> >>> { Reg8|Unspecified|BaseIndex }
> >>> +setzu<cc>, 0xf24<cc:opc>/0, APX_F,
> >>> +Modrm|No_wSuf|No_lSuf|No_sSuf|No_qSuf|EVexMap4|ZU, { Reg8 }
> >>
> >> Didn't we kind of agree to also permit
> >>
> >> set<cc>, 0xf24<cc:opc>/0, APX_F,
> Modrm|No_bSuf|No_sSuf|EVexMap4|ZU,
> >> { Reg32|Reg64 }
> >>
> >
> > We discussed this internally, and the spec folks thought that adding two
> SETZU formats to the spec was a bit redundant and might confuse users.
> Therefore, the spec will not be updated, it's a bit strange that binutils adds a
> separate format.
> 
> People who feel confused can use SETZU. But why make life more difficult for
> people like me, who don't feel confused? If I feel confused by anything, then
> by the odd ZU infix in especially SETZUNZ and SETZUZ. If they want to avoid
> confusion, they can limit ZU as a suffix (Intel) or infix (AT&T) to IMUL, while
> leaving SETcc to remain entirely without.
> 

Personally, I think you always have a good understanding of command formats and names. But I don't have the final say, sorry about that.

Lili.