llvm /
llvm /
fae0ff6ec8d98bb94059496965e76b7e88c949e4 Canonicalize all integer "idempotent" atomicrmw ops
For "idempotent" atomicrmw instructions which we can't simply turn into load, canonicalize the operation and constant. This reduces the matching needed elsewhere in the optimizer, but doesn't directly impact codegen.
For any architecture where OR/Zero is not a good default choice, you can extend the AtomicExpand lowerIdempotentRMWIntoFencedLoad mechanism. I reviewed X86 to make sure this works well, haven't audited other backends.
Differential Revision: https://reviews.llvm.org/D58244
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354058 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed