[Lldb-commits] [lldb] [LLDB][Stats] Calculate active time to first Bt (PR #161604)

[Greg Clayton via lldb-commits]

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@@ -513,6 +518,63 @@ llvm::json::Value DebuggerStats::ReportStatistics(
   return std::move(global_stats);
 }
 
+void TargetStats::SetFirstBtTime(lldb::ProcessSP process_sp, Thread &thread) {
+  if (m_first_bt_time_set)
+    return;
+
+  // Our goal here is to calculate the total active time to get to the first bt
+  // so this will be the target creation time, or the load core time plus all
+  // the time to load and index modules and their debug info.
+  double elapsed_time = 0.0;
+  // GetStackFrameCount can be expensive, but at this point we should
+  // have completed a BT successfully, so the frames should already
+  // exist.
+  for (size_t i = 0; i < thread.GetStackFrameCount(); ++i) {
+    lldb::StackFrameSP frame_sp = thread.GetStackFrameAtIndex(i);
+    if (!frame_sp)
+      continue;
+
+    lldb::ModuleSP module_sp =
+        frame_sp->GetSymbolContext(lldb::eSymbolContextModule).module_sp;
+    if (!module_sp)
+      continue;
+
+    // Add the time it took to load and index the module.
+    elapsed_time += module_sp->GetSymtabParseTime().get().count();
+    elapsed_time += module_sp->GetSymtabParseTime().get().count();
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clayborg wrote:

Why are you doing this twice? And also, why are we adding the symbol table parse time for each stack frame? What if we have a stack with 12 frames from the "a.out" module? Why would we keep adding this? Also, if we are doing a re-use dap scenario, or debugging in Xcode which uses `lldb-rpc-server` then there is no guarantee that the symbol table parsing time would need to be included here if a previous target had already indexes this module.

https://github.com/llvm/llvm-project/pull/161604