[PATCH] D47553: Add TargetLowering::shouldExpandAtomicToLibCall and query it from AtomicExpandPass

[Alex Bradbury via Phabricator via llvm-commits]

asb added a comment.

Thanks Eli, I actually just came to the same conclusion when taking a step back and thinking about it some more. I was caught up on matching RISC-V GCC behaviour in this case, when in fact it seems RISC-V GCC is broken here. The LLVM docs on atomics also do document this requirement https://llvm.org/docs/Atomics.html#atomics-and-codegen. The 'blunt instrument' of MaxSizeInBitsSupported is acting as designed.


Repository:
  rL LLVM

https://reviews.llvm.org/D47553