[all-commits] [llvm/llvm-project] 78abc4: [LoongArch] Improve codegen for atomic cmpxchg ops...

[Lu Weining via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 78abc45c44cdadf76b30e1f3dc24936bb5627d68
      https://github.com/llvm/llvm-project/commit/78abc45c44cdadf76b30e1f3dc24936bb5627d68
  Author: Lu Weining <90239436+SixWeining at users.noreply.github.com>
  Date:   2023-10-19 (Thu, 19 Oct 2023)

  Changed paths:
    M llvm/lib/Target/LoongArch/LoongArchExpandAtomicPseudoInsts.cpp
    M llvm/lib/Target/LoongArch/LoongArchISelLowering.cpp
    M llvm/lib/Target/LoongArch/LoongArchInstrInfo.td
    M llvm/test/CodeGen/LoongArch/ir-instruction/atomic-cmpxchg.ll

  Log Message:
  -----------
  [LoongArch] Improve codegen for atomic cmpxchg ops (#69339)

PR #67391 improved atomic codegen by handling memory ordering specified
by the `cmpxchg` instruction. An acquire barrier needs to be generated
when memory ordering includes an acquire operation. This PR improves the
codegen further by only handling the failure ordering.