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

[Oleksandr Alex Zinenko]

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@@ -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();
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ftynse wrote:

Not exactly, this is more of a hotfix. Generally, we shouldn't transform IR in an irreversible way if the transformation can later fail.

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