[clang] [llvm] Add source file name for template instantiations in -ftime-trace (PR #98320)

[Ilya Biryukov via cfe-commits]

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@@ -60,39 +74,65 @@ bool compileFromString(StringRef Code, StringRef Standard, StringRef FileName) {
   return Compiler.ExecuteAction(Action);
 }
 
+std::string GetMetadata(json::Object *Event) {
+  std::string Metadata = "";
+  if (json::Object *Args = Event->getObject("args")) {
+    if (StringRef Detail = Args->getString("detail").value_or("");
+        !Detail.empty())
+      Metadata += Detail.str();
+    if (StringRef File = Args->getString("filename").value_or("");
+        !File.empty())
+      Metadata += ", " + File.str();
+  }
+  return Metadata;
+}
+
 // Returns pretty-printed trace graph.
 std::string buildTraceGraph(StringRef Json) {
   struct EventRecord {
     int64_t TimestampBegin;
     int64_t TimestampEnd;
-    StringRef Name;
-    StringRef Detail;
+    std::string Name;
+    std::string Metadata;
   };
   std::vector<EventRecord> Events;
 
   // Parse `EventRecord`s from JSON dump.
   Expected<json::Value> Root = json::parse(Json);
   if (!Root)
     return "";
+  std::stack<json::Object *> SourceEvents;
   for (json::Value &TraceEventValue :
        *Root->getAsObject()->getArray("traceEvents")) {
     json::Object *TraceEventObj = TraceEventValue.getAsObject();
 
     int64_t TimestampBegin = TraceEventObj->getInteger("ts").value_or(0);
     int64_t TimestampEnd =
         TimestampBegin + TraceEventObj->getInteger("dur").value_or(0);
-    StringRef Name = TraceEventObj->getString("name").value_or("");
-    StringRef Detail = "";
-    if (json::Object *Args = TraceEventObj->getObject("args"))
-      Detail = Args->getString("detail").value_or("");
+    std::string Name = TraceEventObj->getString("name").value_or("").str();
+    std::string Metadata = GetMetadata(TraceEventObj);
+
+    if (Name == "Source") {
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ilya-biryukov wrote:

But why do we do this in the unit-tests, and not production code, and why do we need to do this in this change?
I am still vague on the motivation for this diff.

https://github.com/llvm/llvm-project/pull/98320