[llvm] [AMDGPU][AsmParser] Support structured HWREG operands. (PR #82805)

[Jay Foad via llvm-commits]

jayfoad wrote:

> I assume this is a syntax sp3 supports?

Yes. I believe SP3 started supporting it in the GFX11 timeframe, but it has backported the syntax to instructions that predate GFX11 like getreg/setreg, and accepts the syntax even when assembling for a pre-GFX11 ASIC.

https://github.com/llvm/llvm-project/pull/82805