[Mlir-commits] [mlir] [mlir][Interfaces] Document completeness requirement of `RegionBranchOpInterface` (PR #202018)

[Mehdi Amini]

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@@ -278,6 +301,13 @@ def RegionBranchOpInterface : OpInterface<"RegionBranchOpInterface"> {
     InterfaceMethod<[{
         Returns the potential branching points (predecessors) for a given
         region successor.
+
+        The returned predecessors must include every `RegionBranchPoint` from
+        which control flow could reach `successor`. Omitting a possible
+        predecessor is an incorrect implementation and may cause
+        analyses/transformations to produce incorrect results. It is acceptable
+        to over-approximate by reporting predecessors that turn out to be
+        infeasible at runtime.
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joker-eph wrote:

Ditto.

https://github.com/llvm/llvm-project/pull/202018