[RISCV][WIP] Add assembler support for Zvma

[FantasqueX]

No description provided.

[topperc]

SiFive has patches for this we are planning to post soon.

[sequencer]

Hi, @topperc we are depending on this for our zvma SW smoke test development this week. 🫣
Is there any schedule for SiFive’s upstreaming plan?
If it’s soon in this week, we will drop this PR, and wait for your work. Otherwise we might miss the AME meeting presentation.
Another choice is asking @FantasqueX adding this as draft until your review or close it until SiFive’s upstreaming their patches.
WDYT?

[kasanovic]

The patch should use custom names, not Zvma, as the extension is not official RVIA spec.

[sequencer]

@kasanovic is fine to change the name to XSfame or some other names, what's your suggestion?

[topperc]

Hi, @topperc we are depending on this for our zvma SW smoke test development this week. 🫣 Is there any schedule for SiFive’s upstreaming plan? If it’s soon in this week, we will drop this PR, and wait for your work. Otherwise we might miss the AME meeting presentation. Another choice is asking @FantasqueX adding this as draft until your review or close it until SiFive’s upstreaming their patches. WDYT?

I have posted our patch. #133031

[sequencer]

Appreciate your work!