[PATCH] D103062: [ObjC][ARC] Ignore operand bundle "clang.arc.attachedcall" on a call if the call's return type is void

[Akira Hatanaka via Phabricator via llvm-commits]

ahatanak created this revision.
ahatanak added a reviewer: fhahn.
ahatanak added a project: LLVM.
Herald added subscribers: dexonsmith, hiraditya.
ahatanak requested review of this revision.

Instead of trying hard to prevent global optimization passes such as deadargelim from changing the return type to void, just ignore the bundle if the return type is void. clang currently emits calls to `@llvm.objc.clang.arc.noop.use`, which consumes the function call result, immediately after the function call to prevent changes to the return type, but optimization passes can delete the call to `@llvm.objc.clang.arc.noop.use` if the function call doesn't return, which enables deadargelim to change the return type.

rdar://76671438


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D103062

Files:
  llvm/include/llvm/Analysis/ObjCARCUtil.h
  llvm/lib/IR/Verifier.cpp
  llvm/test/Transforms/ObjCARC/contract-rv-attr.ll
  llvm/test/Verifier/operand-bundles.ll

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