[llvm] Fix non-determinism in debuginfo (PR #68332)

[Paul Kirth via llvm-commits]

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@@ -314,6 +317,25 @@ class AssignmentTrackingPass : public PassInfoMixin<AssignmentTrackingPass> {
 
 /// Return true if assignment tracking is enabled for module \p M.
 bool isAssignmentTrackingEnabled(const Module &M);
+
+template <> struct DenseMapInfo<at::VarRecord> {
+  static inline at::VarRecord getEmptyKey() {
+    return at::VarRecord{nullptr, nullptr};
+  }
+
+  static inline at::VarRecord getTombstoneKey() {
+    return at::VarRecord{nullptr, nullptr};
+  }
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ilovepi wrote:

Thank you. I was 90% sure I was doing this wrong. 

https://github.com/llvm/llvm-project/pull/68332