[lldb] Add count for number of DWO files loaded in statistics

lldb/include/lldb/Symbol/SymbolFile.h

@@ -425,6 +425,11 @@ class SymbolFile : public PluginInterface {
   /// Reset the statistics for the symbol file.
   virtual void ResetStatistics() {}
 
+  /// Get the number of loaded DWO files for this symbol file.
+  /// This is used for statistics gathering and will return 0 for most
+  /// symbol file implementations except DWARF symbol files.
+  virtual uint32_t GetLoadedDwoFileCount() const { return 0; }
+
   /// Get the additional modules that this symbol file uses to parse debug info.
   ///
   /// Some debug info is stored in stand alone object files that are represented

lldb/packages/Python/lldbsuite/test/builders/builder.py

@@ -247,13 +247,24 @@ def getLLDBObjRoot(self):
     def _getDebugInfoArgs(self, debug_info):
         if debug_info is None:
             return []
-        if debug_info == "dwarf":
-            return ["MAKE_DSYM=NO"]
-        if debug_info == "dwo":
-            return ["MAKE_DSYM=NO", "MAKE_DWO=YES"]
-        if debug_info == "gmodules":
-            return ["MAKE_DSYM=NO", "MAKE_GMODULES=YES"]
-        return None
+
+        debug_options = debug_info if isinstance(debug_info, list) else [debug_info]
+        option_flags = {
+            "dwarf": {"MAKE_DSYM": "NO"},
+            "dwo": {"MAKE_DSYM": "NO", "MAKE_DWO": "YES"},
+            "gmodules": {"MAKE_DSYM": "NO", "MAKE_GMODULES": "YES"},
+            "debug_names": {"MAKE_DEBUG_NAMES": "YES"},
+        }
+
+        # Collect all flags, with later options overriding earlier ones
+        flags = {}
+
+        for option in debug_options:
+            if not option or option not in option_flags:
+                return None # Invalid options
+            flags.update(option_flags[option])
+
+        return [f"{key}={value}" for key, value in flags.items()]
 
     def getBuildCommand(
         self,

lldb/packages/Python/lldbsuite/test/make/Makefile.rules

@@ -276,6 +276,10 @@ ifeq "$(MAKE_DWO)" "YES"
 	CFLAGS += -gsplit-dwarf
 endif
 
+ifeq "$(MAKE_DEBUG_NAMES)" "YES"
+	CFLAGS += -gpubnames
+endif
+
 ifeq "$(USE_PRIVATE_MODULE_CACHE)" "YES"
 THE_CLANG_MODULE_CACHE_DIR := $(BUILDDIR)/private-module-cache
 else

lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp

@@ -4358,6 +4358,7 @@ StatsDuration::Duration SymbolFileDWARF::GetDebugInfoIndexTime() {
 
 void SymbolFileDWARF::ResetStatistics() {
   m_parse_time.reset();
+  m_loaded_dwo_file_count = 0;
   if (m_index)
     return m_index->ResetStatistics();
 }

lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h

@@ -315,6 +315,11 @@ class SymbolFileDWARF : public SymbolFileCommon {
 
   void ResetStatistics() override;
 
+  /// Get the number of loaded DWO files for this symbol file
+  uint32_t GetLoadedDwoFileCount() const override {
+    return m_loaded_dwo_file_count;
+  }
+
   virtual lldb::offset_t
   GetVendorDWARFOpcodeSize(const DataExtractor &data,
                            const lldb::offset_t data_offset,
@@ -497,6 +502,8 @@ class SymbolFileDWARF : public SymbolFileCommon {
 
   void InitializeFirstCodeAddress();
 
+  void IncrementLoadedDwoFileCount() { m_loaded_dwo_file_count++; }
+
   void
   GetCompileOptions(std::unordered_map<lldb::CompUnitSP, Args> &args) override;
 
@@ -550,6 +557,8 @@ class SymbolFileDWARF : public SymbolFileCommon {
   /// valid value that can be used in DIERef objects which will contain
   /// an index that identifies the .DWO or .o file.
   std::optional<uint64_t> m_file_index;
+  /// Count of loaded DWO files for this symbol file
+  uint32_t m_loaded_dwo_file_count = 0;
 };
 } // namespace dwarf
 } // namespace lldb_private::plugin

lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.cpp

@@ -31,7 +31,7 @@ SymbolFileDWARFDwo::SymbolFileDWARFDwo(SymbolFileDWARF &base_symbol_file,
                                    /*update_module_section_list*/ false)),
       m_base_symbol_file(base_symbol_file) {
   SetFileIndex(id);
-
+  m_base_symbol_file.IncrementLoadedDwoFileCount();
   // Parsing of the dwarf unit index is not thread-safe, so we need to prime it
   // to enable subsequent concurrent lookups.
   m_context.GetAsLLVM().getCUIndex();

lldb/source/Target/Statistics.cpp

@@ -322,6 +322,7 @@ llvm::json::Value DebuggerStats::ReportStatistics(
   uint32_t num_modules_with_incomplete_types = 0;
   uint32_t num_stripped_modules = 0;
   uint32_t symtab_symbol_count = 0;
+  uint32_t total_loaded_dwo_file_count = 0;
   for (size_t image_idx = 0; image_idx < num_modules; ++image_idx) {
     Module *module = target != nullptr
                          ? target->GetImages().GetModuleAtIndex(image_idx).get()
@@ -353,6 +354,9 @@ llvm::json::Value DebuggerStats::ReportStatistics(
         for (const auto &symbol_module : symbol_modules.Modules())
           module_stat.symfile_modules.push_back((intptr_t)symbol_module.get());
       }
+      // Add DWO file count from this symbol file (will be 0 for non-DWARF
+      // symbol files)
+      total_loaded_dwo_file_count += sym_file->GetLoadedDwoFileCount();
       module_stat.debug_info_index_loaded_from_cache =
           sym_file->GetDebugInfoIndexWasLoadedFromCache();
       if (module_stat.debug_info_index_loaded_from_cache)
@@ -427,6 +431,7 @@ llvm::json::Value DebuggerStats::ReportStatistics(
       {"totalDebugInfoEnabled", num_debug_info_enabled_modules},
       {"totalSymbolTableStripped", num_stripped_modules},
       {"totalSymbolTableSymbolCount", symtab_symbol_count},
+      {"totalLoadedDwoFileCount", total_loaded_dwo_file_count},
   };
 
   if (include_targets) {

lldb/test/API/commands/statistics/basic/TestStats.py

@@ -177,6 +177,7 @@ def test_default_no_run(self):
             "totalDebugInfoIndexLoadedFromCache",
             "totalDebugInfoIndexSavedToCache",
             "totalDebugInfoParseTime",
+            "totalLoadedDwoFileCount",
         ]
         self.verify_keys(debug_stats, '"debug_stats"', debug_stat_keys, None)
         if self.getPlatform() != "windows":
@@ -287,6 +288,7 @@ def test_default_with_run(self):
             "totalDebugInfoIndexLoadedFromCache",
             "totalDebugInfoIndexSavedToCache",
             "totalDebugInfoParseTime",
+            "totalLoadedDwoFileCount",
         ]
         self.verify_keys(debug_stats, '"debug_stats"', debug_stat_keys, None)
         stats = debug_stats["targets"][0]
@@ -325,6 +327,7 @@ def test_memory(self):
             "totalDebugInfoIndexLoadedFromCache",
             "totalDebugInfoIndexSavedToCache",
             "totalDebugInfoByteSize",
+            "totalLoadedDwoFileCount",
         ]
         self.verify_keys(debug_stats, '"debug_stats"', debug_stat_keys, None)
 
@@ -377,6 +380,7 @@ def test_modules(self):
             "totalDebugInfoIndexLoadedFromCache",
             "totalDebugInfoIndexSavedToCache",
             "totalDebugInfoByteSize",
+            "totalLoadedDwoFileCount",
         ]
         self.verify_keys(debug_stats, '"debug_stats"', debug_stat_keys, None)
         stats = debug_stats["targets"][0]
@@ -485,6 +489,7 @@ def test_breakpoints(self):
             "totalDebugInfoIndexLoadedFromCache",
             "totalDebugInfoIndexSavedToCache",
             "totalDebugInfoByteSize",
+            "totalLoadedDwoFileCount",
         ]
         self.verify_keys(debug_stats, '"debug_stats"', debug_stat_keys, None)
         target_stats = debug_stats["targets"][0]
@@ -512,6 +517,32 @@ def test_breakpoints(self):
             self.verify_keys(
                 breakpoint, 'target_stats["breakpoints"]', bp_keys_exist, None
             )
+
+    def test_loaded_dwo_file_count(self):
+        """
+        Test "statistics dump" and the loaded dwo file count.
+        Builds a binary w/ separate .dwo files and debug_names, and then
+        verifies the loaded dwo file count is the expected count after running
+        various commands
+        """
+        da = {"CXX_SOURCES": "third.cpp baz.cpp", "EXE": self.getBuildArtifact("a.out")}
+        self.build(dictionary=da, debug_info=["dwo", "debug_names"])
+        self.addTearDownCleanup(dictionary=da)
+        exe = self.getBuildArtifact("a.out")
+        target = self.createTestTarget(file_path=exe)
+        debug_stats = self.get_stats()
+
+        self.assertIn("totalLoadedDwoFileCount", debug_stats)
+        self.assertEqual(debug_stats["totalLoadedDwoFileCount"], 0)
+
+        self.runCmd("b main")
+        debug_stats_after_main = self.get_stats()
+        self.assertEqual(debug_stats_after_main["totalLoadedDwoFileCount"], 1)
+
+        self.runCmd("type lookup Baz")
+        debug_stats_after_type_lookup = self.get_stats()
+        self.assertEqual(debug_stats_after_type_lookup["totalLoadedDwoFileCount"], 2)
+
 
     @skipUnlessDarwin
     @no_debug_info_test

lldb/test/API/commands/statistics/basic/baz.cpp

@@ -0,0 +1,12 @@
+// Helper that the lldb command `statistics dump` works in split-dwarf mode.
+
+struct Baz {
+  int x;
+  bool y;
+};
+
+void baz() {
+  Baz b;
+  b.x = 1;
+  b.y = true;
+}

lldb/test/API/commands/statistics/basic/third.cpp

@@ -0,0 +1,7 @@
+// Test that the lldb command `statistics dump` works.
+
+void baz();
+int main(void) {
+  baz();
+  return 0;
+}