Adopt "pretty accessors" in MLIR

[lattner]

MLIR mainline added the ability to synthesize get/setters with a properly camel cased and get/set-prefixed name, see this patch and this announcement.

We should do a merge from MLIR mainline to get this, and then adopt it in the CIRCT dialects. I don't think we need to do the multistage adoption thing, we can just jump directly to _Prefixed

[thatTPR]

Should this be closed or is it still available?

[lattner]

I think the Merge was done, but we haven't adopted the new names yet.

[maerhart]

There were still a few things missing in MLIR-tablegen to generate printers from the assembly-format etc. with the new prefixes which were addressed in https://github.com/llvm/llvm-project/commit/6a99423390995f874ee4e345157523f4139ccbef We should bump the LLVM version to that first. It might also make sense to wait until MLIR switches the default to 'Both' here, then we can avoid setting that flag separately for every dialect.

[lattner]

Aha, right, I thought we already had that, thanks.

[maerhart]

Dialects that have adopted prefixed accessors so far:

• [ ] Calyx
• [x] Comb
• [ ] ESI
• [x] FIRRTL
• [ ] FSM
• [ ] Handshake
• [x] HW
• [ ] HWArith
• [x] LLHD
• [x] Moore
• [ ] MSFT
• [x] Seq
• [ ] StaticLogic
• [x] SV