[clang] [llvm] Added instant events and marking defered templated instantiation. (PR #103039)

[Ilya Biryukov via cfe-commits]

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@@ -104,6 +105,23 @@ struct llvm::TimeTraceProfilerEntry {
   }
 };
 
+struct InProgressEntry {
+  std::unique_ptr<TimeTraceProfilerEntry> Event;
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ilya-biryukov wrote:

Could we store it directly as `TimeTraceProfilerEntry` without unique_ptr?
We are already creating `InProgressEntry` in the heap, so the stability of pointers for its members should be guaranteed.

Having exactly one of `InProgressEntry` or the corresponding `TimeTraceProfilerEntry` in the heap should be enough.

https://github.com/llvm/llvm-project/pull/103039