[llvm] Revert "[NVPTX] Add Volta Load/Store Atomics (.relaxed, .acquire, .release) and Volatile (.mmio/.volatile) support" (PR #99695)

[via llvm-commits]

gonzalobg wrote:

The problem is that XLA is using `atomic unordered` in their code generation, which the patch being reverted here disabled because it was not supported by the NVPTX backend (the code generation for it was just accidentally falling through a branch causing it to "do something incorrect").

This looks like a mistake on XLA's side, which should be using `atomic monotonic` instead.

#99709 updates this patch to provide `atomic unordered` the same code-generation as `atomic monotonic`.


https://github.com/llvm/llvm-project/pull/99695