[Mlir-commits] [mlir] [mlir][Transforms] Fix crash in `CFGToSCF` when conversion fails (PR #173590)

[NohHyeon Kwon]

================
@@ -1156,8 +1156,10 @@ static FailureOr<SmallVector<Block *>> transformToStructuredCFBranches(
     FailureOr<Operation *> result = interface.createStructuredBranchRegionOp(
         opBuilder, regionEntry->getTerminator(),
         continuation->getArgumentTypes(), conditionalRegions);
-    if (failed(result))
+    if (failed(result)) {
+      regionEntry->getTerminator()->dropAllReferences();
----------------
swote-git wrote:

I missed that point about the invalid IR state.
I've updated the latest commit to splice the blocks back to the parent region.
Please let me know if this looks right.

https://github.com/llvm/llvm-project/pull/173590