[llvm-branch-commits] [llvm] release/23.x: [RISCV] Add macro fusion support for the Xqci extension instructions (#209542) (PR #212779)

[Tobias Hieta via llvm-branch-commits]

tru wrote:

Now that we're past rc2, I'm inclined to close this as `Won't Merge` — this reads as adding new macro-fusion scheduling support for the Xqci extension rather than fixing a bug/regression, which is what we're limiting backports to at this stage. It also grows `MAX_SUBTARGET_WORDS` from 6 to 7 in `SubtargetFeature.h`, increasing the size of `FeatureBitset` used by value across every target — a real ABI-layout change that wasn't discussed in review. If you think this should still go in, can you provide justification (why it's needed now vs. next release) and an assessment of the risk/blast radius?

https://github.com/llvm/llvm-project/pull/212779