[clang] [llvm] [RISCV] Add QingKe "XW" compressed opcode extension (PR #97925)

[via llvm-commits]

ArcaneNibble wrote:

Updated the newly-added `clang/test/Driver/print-supported-extensions-riscv.c` test (in addition to simply rebasing)

(I don't normally run *all* tests because of how long it takes, so I didn't notice this change until it failed in CI)

https://github.com/llvm/llvm-project/pull/97925