[Lldb-commits] [lldb] Fix dap stacktrace perf issue (PR #104874)

[via lldb-commits]

https://github.com/jeffreytan81 updated https://github.com/llvm/llvm-project/pull/104874

>From 6e84ab9a14e63c58e1facdbf9a695c093882b37b Mon Sep 17 00:00:00 2001
From: jeffreytan81 <jeffreytan at fb.com>
Date: Mon, 19 Aug 2024 10:57:35 -0700
Subject: [PATCH 1/2] Fix StartDebuggingRequestHandler/ReplModeRequestHandler
 in lldb-dap

---
 lldb/tools/lldb-dap/DAP.h        | 2 --
 lldb/tools/lldb-dap/lldb-dap.cpp | 4 ++--
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/lldb/tools/lldb-dap/DAP.h b/lldb/tools/lldb-dap/DAP.h
index 57562a14983519..7828272aa15a7d 100644
--- a/lldb/tools/lldb-dap/DAP.h
+++ b/lldb/tools/lldb-dap/DAP.h
@@ -192,8 +192,6 @@ struct DAP {
   std::mutex call_mutex;
   std::map<int /* request_seq */, ResponseCallback /* reply handler */>
       inflight_reverse_requests;
-  StartDebuggingRequestHandler start_debugging_request_handler;
-  ReplModeRequestHandler repl_mode_request_handler;
   ReplMode repl_mode;
   std::string command_escape_prefix = "`";
   lldb::SBFormat frame_format;
diff --git a/lldb/tools/lldb-dap/lldb-dap.cpp b/lldb/tools/lldb-dap/lldb-dap.cpp
index ea84f31aec3a6c..f50a6c17310739 100644
--- a/lldb/tools/lldb-dap/lldb-dap.cpp
+++ b/lldb/tools/lldb-dap/lldb-dap.cpp
@@ -1627,12 +1627,12 @@ void request_initialize(const llvm::json::Object &request) {
       "lldb-dap", "Commands for managing lldb-dap.");
   if (GetBoolean(arguments, "supportsStartDebuggingRequest", false)) {
     cmd.AddCommand(
-        "startDebugging", &g_dap.start_debugging_request_handler,
+        "startDebugging", new StartDebuggingRequestHandler(),
         "Sends a startDebugging request from the debug adapter to the client "
         "to start a child debug session of the same type as the caller.");
   }
   cmd.AddCommand(
-      "repl-mode", &g_dap.repl_mode_request_handler,
+      "repl-mode", new ReplModeRequestHandler(),
       "Get or set the repl behavior of lldb-dap evaluation requests.");
 
   g_dap.progress_event_thread = std::thread(ProgressEventThreadFunction);

>From 00f62e2d4cd067b6c46a7646ff152ceae808b1f4 Mon Sep 17 00:00:00 2001
From: jeffreytan81 <jeffreytan at fb.com>
Date: Mon, 19 Aug 2024 14:01:54 -0700
Subject: [PATCH 2/2] Fix stackTrace perf issue in lldb-dap

---
 lldb/tools/lldb-dap/DAP.cpp      |  1 +
 lldb/tools/lldb-dap/DAP.h        |  1 +
 lldb/tools/lldb-dap/lldb-dap.cpp | 15 +++++++++++----
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/lldb/tools/lldb-dap/DAP.cpp b/lldb/tools/lldb-dap/DAP.cpp
index 1fd560f21904ab..57b93c28ce9301 100644
--- a/lldb/tools/lldb-dap/DAP.cpp
+++ b/lldb/tools/lldb-dap/DAP.cpp
@@ -36,6 +36,7 @@ DAP::DAP()
       focus_tid(LLDB_INVALID_THREAD_ID), stop_at_entry(false), is_attach(false),
       enable_auto_variable_summaries(false),
       enable_synthetic_child_debugging(false),
+      enable_display_extended_backtrace(false),
       restarting_process_id(LLDB_INVALID_PROCESS_ID),
       configuration_done_sent(false), waiting_for_run_in_terminal(false),
       progress_event_reporter(
diff --git a/lldb/tools/lldb-dap/DAP.h b/lldb/tools/lldb-dap/DAP.h
index 27ea6c7ff8423f..0fc77ac1e81683 100644
--- a/lldb/tools/lldb-dap/DAP.h
+++ b/lldb/tools/lldb-dap/DAP.h
@@ -181,6 +181,7 @@ struct DAP {
   bool is_attach;
   bool enable_auto_variable_summaries;
   bool enable_synthetic_child_debugging;
+  bool enable_display_extended_backtrace;
   // The process event thread normally responds to process exited events by
   // shutting down the entire adapter. When we're restarting, we keep the id of
   // the old process here so we can detect this case and keep running.
diff --git a/lldb/tools/lldb-dap/lldb-dap.cpp b/lldb/tools/lldb-dap/lldb-dap.cpp
index 7b83767d1afeab..495ed0256120e8 100644
--- a/lldb/tools/lldb-dap/lldb-dap.cpp
+++ b/lldb/tools/lldb-dap/lldb-dap.cpp
@@ -701,6 +701,8 @@ void request_attach(const llvm::json::Object &request) {
       GetBoolean(arguments, "enableAutoVariableSummaries", false);
   g_dap.enable_synthetic_child_debugging =
       GetBoolean(arguments, "enableSyntheticChildDebugging", false);
+  g_dap.enable_display_extended_backtrace =
+      GetBoolean(arguments, "enableDisplayExtendedBacktrace", false);
   g_dap.command_escape_prefix =
       GetString(arguments, "commandEscapePrefix", "`");
   g_dap.SetFrameFormat(GetString(arguments, "customFrameFormat"));
@@ -1925,6 +1927,8 @@ void request_launch(const llvm::json::Object &request) {
       GetBoolean(arguments, "enableAutoVariableSummaries", false);
   g_dap.enable_synthetic_child_debugging =
       GetBoolean(arguments, "enableSyntheticChildDebugging", false);
+  g_dap.enable_display_extended_backtrace =
+      GetBoolean(arguments, "enableDisplayExtendedBacktrace", false);
   g_dap.command_escape_prefix =
       GetString(arguments, "commandEscapePrefix", "`");
   g_dap.SetFrameFormat(GetString(arguments, "customFrameFormat"));
@@ -3111,8 +3115,9 @@ void request_stackTrace(const llvm::json::Object &request) {
     // This will always return an invalid thread when
     // libBacktraceRecording.dylib is not loaded or if there is no extended
     // backtrace.
-    lldb::SBThread queue_backtrace_thread =
-        thread.GetExtendedBacktraceThread("libdispatch");
+    lldb::SBThread queue_backtrace_thread;
+    if (g_dap.enable_display_extended_backtrace)
+      queue_backtrace_thread = thread.GetExtendedBacktraceThread("libdispatch");
     if (queue_backtrace_thread.IsValid()) {
       // One extra frame as a label to mark the enqueued thread.
       totalFrames += queue_backtrace_thread.GetNumFrames() + 1;
@@ -3120,8 +3125,10 @@ void request_stackTrace(const llvm::json::Object &request) {
 
     // This will always return an invalid thread when there is no exception in
     // the current thread.
-    lldb::SBThread exception_backtrace_thread =
-        thread.GetCurrentExceptionBacktrace();
+    lldb::SBThread exception_backtrace_thread;
+    if (g_dap.enable_display_extended_backtrace)
+      exception_backtrace_thread = thread.GetCurrentExceptionBacktrace();
+
     if (exception_backtrace_thread.IsValid()) {
       // One extra frame as a label to mark the exception thread.
       totalFrames += exception_backtrace_thread.GetNumFrames() + 1;