[Mlir-commits] [mlir] [MLIR] Fuse parent region location when hoisting constants (PR #75258)

[Billy Zhu]

zyx-billy wrote:

So I saw [this comment](https://github.com/llvm/llvm-project/pull/74670#issuecomment-1854587470) from the previous PR warning about OOM / timeouts, and I wonder if we need to make a tradeoff between tracking everything & efficiency.

Would you be open to doing something lossy, like what was done in LLVM, where whenever we move / materialize / deduplicate constants, we just set the location to the parent location (and throw away the original locations). That achieves the same ultimate effect (clearer op location meaning & no out-of-order stepping) without dragging all the original source locations along. While it may feel weird throwing away locations, that's essentially what was done before the previous PR (except for an arbitrary one that was kept).

https://github.com/llvm/llvm-project/pull/75258