[llvm] [Utils] Fix incorrect LCSSA PHI nodes when splitting critical edges with MergeIdenticalEdges (PR #131744)

[Nikita Popov via llvm-commits]

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@@ -438,6 +438,63 @@ define void @crit_edge(i1 %cond0, i1 %cond1) {
   EXPECT_TRUE(PDT.verify());
 }
 
+TEST(BasicBlockUtils, SplitLoopCriticalEdge) {
+  LLVMContext C;
+  std::unique_ptr<Module> M = parseIR(C, R"IR(
+declare dso_local i1 @predicate(ptr noundef %p)
+
+define dso_local ptr @Parse(ptr noundef %gp) {
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nikic wrote:

Drop the unnecessary dso_local / noundef.

https://github.com/llvm/llvm-project/pull/131744