[flang] [llvm] [clang-tools-extra] [clang] [libcxx] [libc] [compiler-rt] [AMDGPU] Produce better memoperand for LDS DMA (PR #75247)

[Jay Foad via cfe-commits]

jayfoad wrote:

> Use PoisonValue instead of nullptr for load memop as a Value.

What is the effect of that? I thought nullptr was supposed to represent an unknown value, so you have to conservatively assume it might alias with anything.

https://github.com/llvm/llvm-project/pull/75247