[Mlir-commits] [mlir] [MLIR][LLVM] Block address support (PR #134335)

[Tobias Gysi]

https://github.com/gysit commented:

Yet another try to comment on the correct pr...

As probably have realized the block address semantics is quite tricky to replicate in MLIR and we probably have to make sure certain optimizations don't apply:
- Inlining should not happen if a function contains a tag (I commented hopefully on the right PR who to prevent inlinig)
- The unreachable block issue should probably result in an hard error since there is not much we can do if there is a tag in an unreachable block?
- What happens if MLIR merges two block (e.g. when running region simplify) with different tags? I guess this could still be exported but the LLVM IR before and after MLIR would be semantically different since two block addresses would be merged into one block address. Does LLVM proper also merge block addresses if two blocks can be merged?

https://github.com/llvm/llvm-project/pull/134335