[PATCH v1] x86: Change padlock instructions prefix as rep

[Jan Beulich]

On 16.12.2024 08:03, Mayshao-oc wrote:
> Hi all:
>   This patch change the display of all padlock instructions prefix 
> from repz to rep, because padlock instructions don't effect zf flag.

"Affect" doesn't matter for REP/REPZ/REPNZ. What may matter is that ZF
isn't checked by these insns. However, can you confirm that on the VIA
CPUs the same opcodes prefixed with REPNZ wouldn't have the same
behavior? I have a sneaking suspicion that while not documented that
way, either REP would have been "fine" (just like is the case for e.g.
LODS, MOVS, and STOS). If that was the case, then sticking to REPZ in
disassembly may be better.

As to the actual changes, two remarks:

Why do you fiddle with the comments in gas/testsuite/gas/i386/padlock.s,
opcodes/i386-opc.h, and opcodes/i386-opc.tbl? (Even if that was
appropriate for some reason, please can you avoid spelling Zhaoxin all
uppercase? That's the cosmetic adjustment which I meant to do to the
earlier patch that Haochen ended up rushing in. Aiui VIA is an
abbreviation while Zhaoxin isn't.)

In the comment immediately ahead of PADLOCK_Fixup() you want to change
from singular to plural, now that the function deals with multiple
insns.

As to the mechanical ChangeLog - you don't really delete MONTMUL_Fixup()
and introduce a brand new PADLOCK_Fixup(). Instead you rename the former
to the latter.

Jan