[PATCH] D50339: Consistently use MemoryLocation::UnknownSize to indicate unknown access size

[Matthias Braun via Phabricator via llvm-commits]

MatzeB added a comment.

First: My experience with MachineMemOperands is limited, so feel free to correct me where necessary.

About 1): I was always told that machine memory operands are optional to give additional information to alias analysis or relax atomicity constraints. However I assumed one of the basic rules is that dropping them will not introduce correctness problems. Operations without machine mem operands should be handled as conservatively as possible.

About 2), 3): I'd be fine with that if we have a good use case. But shouldn't we naturally know the size of memory operations in the backend? I can't think of any architecture right now where we wouldn't be able to know the size of a memory operation...


Repository:
  rL LLVM

https://reviews.llvm.org/D50339