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

[Mehdi Amini]

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@@ -247,6 +263,13 @@ def RegionBranchOpInterface : OpInterface<"RegionBranchOpInterface"> {
     InterfaceMethod<[{
         Returns the potential region successors when branching from any
         terminator in `region`.
+
+        The returned successors must include every region successor that any
+        `RegionBranchTerminatorOpInterface` terminator in `region` could
+        branch to. Omitting a successor reachable from any such terminator is
+        an incorrect implementation and may cause analyses/transformations to
+        produce incorrect results. It is acceptable to over-approximate by
+        reporting successors that turn out to be infeasible at runtime.
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joker-eph wrote:

Likewise.

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