[Mlir-commits] [mlir] [mlir][reducer] Change mlir-reducer apply pattern logic (PR #195997)

[llvmlistbot at llvm.org]

aidint wrote:

@linuxlonelyeagle no worries, I don't have commit access yet. Thank you for pinging me here. 

I don't believe this solves the core issue. Seems to me that this will cause segfault if both of these are true:
1. The root module is interesting because of a trivially dead operation
2. `eraseOpsNotInRange` is `false`

With these changes, bug is pushed to a further point in the flow. So basically this can happen on second `findOptimal` invocation, specifically here: https://github.com/linuxlonelyeagle/llvm-project/blob/8d849fb6e4e84186ae86ca6055c1fe64b4f84804/mlir/lib/Reducer/ReductionTreePass.cpp#L207

https://github.com/llvm/llvm-project/pull/195997