[llvm] [SandboxVec][DependencyGraph] Fix dependency node iterators (PR #125616)

[Sriraman Tallam via llvm-commits]

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@@ -14,6 +14,20 @@
 
 namespace llvm::sandboxir {
 
+User::op_iterator PredIterator::skipBadIt(User::op_iterator OpIt,
+                                          User::op_iterator OpItE,
+                                          const DependencyGraph &DAG) {
+  auto Skip = [&DAG](auto OpIt) {
+    auto *I = dyn_cast<Instruction>((*OpIt).get());
+    if (I == nullptr)
+      return true;
+    return DAG.getNode(I) == nullptr;
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tmsri wrote:

return (I == nullptr || DAG.getNode(I) == nullptr);

https://github.com/llvm/llvm-project/pull/125616