[PATCH v1] x86: Support ZHAOXIN padlock instructions

[Jiang, Haochen]

> From: Mayshao-oc <Mayshao-oc@zhaoxin.com>
> Sent: Friday, December 13, 2024 11:25 AM
> 
> Hi all:
> 
>       This patch adds support for Zhaoxin padlock instructions, and display all the
> padlock instructions using rep prefix instead of repz, because all padlock
> instructions don't effect zf flag.
> 

A quick reminder. From documentation, it seems that Zhaoxin is going to extend
the usage for old bits for new instructions. If you are only using inline asm in the
future (and I suppose so since I did not get PadLock in GCC code base from my quick
search), it should be ok. But there will be a potential issue for illegal instruction on
HW if the assumption is wrong since I don't see a way to reject those insts.

For the patch, could you split it into two patch, one to replace repz and one to add
new insts? It will help to get a clearer picture on refactoring.

Thx,
Haochen