[llvm] [SPIR-V] Add SPIR-V structurizer (PR #97606)

[Nathan Gauër via llvm-commits]

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@@ -230,7 +230,8 @@ class ConvergenceRegionAnalyzer {
     auto *Terminator = From->getTerminator();
     for (unsigned i = 0; i < Terminator->getNumSuccessors(); ++i) {
       auto *To = Terminator->getSuccessor(i);
-      if (isBackEdge(From, To))
+      // Ignore back edges and self edges.
+      if (From == To || isBackEdge(From, To))
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Keenuts wrote:

Yes, now that you say it... 🙃 Removed the bogus assert in isBackEdge and reverted this.

https://github.com/llvm/llvm-project/pull/97606