Add target modules dump separate-debug-info (#66035)

Add a new command
```
target modules dump separate-debug-info [-j] [<filename> [<filename> [...]]]
```
or
```
image dump separate-debug-info [-j] [<filename> [<filename> [...]]]
```
(since `image` is an alias for `target modules`).
This lists the separate debug info files and their current status
(loaded or not loaded) for the specified modules. This diff implements
this command for mach-O files with OSO and ELF files with dwo.
Example dwo:
```
(lldb) image dump separate-debug-info
Symbol file: /home/toyang/workspace/dwo-scratch/a.out
Type: "dwo"
Dwo ID             Err Dwo Path
------------------ --- -----------------------------------------
0x9a429da5abb6faae     /home/toyang/workspace/scratch-dwo/a-main.dwo
0xbcc129959e76ff33     /home/toyang/workspace/scratch-dwo/a-foo.dwo

(lldb) image dump separate-debug-info -j
[
  {
    "separate-debug-info-files": [
      {
        "comp_dir": "/home/toyang/workspace/dwo-scratch",
        "dwo_id": 11115620165179865774,
        "dwo_name": "a-main.dwo",
        "loaded": true,
        "resolved_dwo_path": "/home/toyang/workspace/dwo-scratch/a-main.dwo"
      },
      {
        "comp_dir": "/home/toyang/workspace/dwo-scratch",
        "dwo_id": 13601198072221073203,
        "dwo_name": "a-foo.dwo",
        "loaded": true,
        "resolved_dwo_path": "/home/toyang/workspace/dwo-scratch/a-foo.dwo"
      }
    ],
    "symfile": "/home/toyang/workspace/dwo-scratch/a.out",
    "type": "dwo"
  }
]
```
Example dwo with missing dwo:
```
(lldb) image dump separate-debug-info
Symbol file: /home/toyang/workspace/dwo-scratch/a.out
Type: "dwo"
Dwo ID             Err Dwo Path
------------------ --- -----------------------------------------
0x9a429da5abb6faae E   unable to locate .dwo debug file "/home/toyang/workspace/scratch-dwo/b.out-main.dwo" for skeleton DIE 0x0000000000000014
0xbcc129959e76ff33 E   unable to locate .dwo debug file "/home/toyang/workspace/scratch-dwo/b.out-foo.dwo" for skeleton DIE 0x000000000000003c

(lldb) image dump separate-debug-info -j
[
  {
    "separate-debug-info-files": [
      {
        "comp_dir": "/home/toyang/workspace/dwo-scratch",
        "dwo_id": 11115620165179865774,
        "dwo_name": "a-main.dwo",
        "error": "unable to locate .dwo debug file \"/home/toyang/workspace/dwo-scratch/a-main.dwo\" for skeleton DIE 0x0000000000000014",
        "loaded": false
      },
      {
        "comp_dir": "/home/toyang/workspace/dwo-scratch",
        "dwo_id": 13601198072221073203,
        "dwo_name": "a-foo.dwo",
        "error": "unable to locate .dwo debug file \"/home/toyang/workspace/dwo-scratch/a-foo.dwo\" for skeleton DIE 0x000000000000003c",
        "loaded": false
      }
    ],
    "symfile": "/home/toyang/workspace/dwo-scratch/a.out",
    "type": "dwo"
  }
]
```
Example output with dwp:
```
(lldb) image dump separate-debug-info
Symbol file: /home/toyang/workspace/dwo-scratch/a.out
Type: "dwo"
Dwo ID             Err Dwo Path
------------------ --- -----------------------------------------
0x9a429da5abb6faae     /home/toyang/workspace/dwo-scratch/a.out.dwp(a-main.dwo)
0xbcc129959e76ff33     /home/toyang/workspace/dwo-scratch/a.out.dwp(a-foo.dwo)
(lldb) image dump separate-debug-info -j
[
  {
    "separate-debug-info-files": [
      {
        "comp_dir": "/home/toyang/workspace/dwo-scratch",
        "dwo_id": 11115620165179865774,
        "dwo_name": "a-main.dwo",
        "loaded": true,
        "resolved_dwo_path": "/home/toyang/workspace/dwo-scratch/a.out.dwp"
      },
      {
        "comp_dir": "/home/toyang/workspace/dwo-scratch",
        "dwo_id": 13601198072221073203,
        "dwo_name": "a-foo.dwo",
        "loaded": true,
        "resolved_dwo_path": "/home/toyang/workspace/dwo-scratch/a.out.dwp"
      }
    ],
    "symfile": "/home/toyang/workspace/dwo-scratch/a.out",
    "type": "dwo"
  }
]
```
Example oso on my Mac:
```
(lldb) image dump separate-debug-info
Symbol file: /Users/toyang/workspace/scratch/a.out
Type: "oso"
Mod Time           Err Oso Path
------------------ --- ---------------------
0x0000000064e64868     /Users/toyang/workspace/scratch/foo.a(foo.o)
0x0000000064e64868     /Users/toyang/workspace/scratch/foo.a(main.o)

(lldb) image dump separate-debug-info -j
[
  {
    "separate-debug-info-files": [
      {
        "loaded": true,
        "oso_mod_time": 1692813416,
        "oso_path": "/Users/toyang/workspace/scratch/foo.a(foo.o)",
        "so_file": "/Users/toyang/workspace/scratch/foo.cpp"
      },
      {
        "loaded": true,
        "oso_mod_time": 1692813416,
        "oso_path": "/Users/toyang/workspace/scratch/foo.a(main.o)",
        "so_file": "/Users/toyang/workspace/scratch/main.cpp"
      }
    ],
    "symfile": "/Users/toyang/workspace/scratch/a.out",
    "type": "oso"
  }
]
```

Test Plan:
Tested on Mac OS and Linux.
```
lldb-dotest -p TestDumpDwo
lldb-dotest -p TestDumpOso
```

---------

Co-authored-by: Tom Yang <toyang@fb.com>

lldb/include/lldb/Symbol/SymbolFile.h

@@ -22,6 +22,7 @@
 #include "lldb/Symbol/TypeList.h"
 #include "lldb/Symbol/TypeSystem.h"
 #include "lldb/Target/Statistics.h"
+#include "lldb/Utility/StructuredData.h"
 #include "lldb/Utility/XcodeSDK.h"
 #include "lldb/lldb-private.h"
 #include "llvm/ADT/DenseSet.h"
@@ -434,6 +435,18 @@ class SymbolFile : public PluginInterface {
   virtual bool GetDebugInfoHadFrameVariableErrors() const = 0;
   virtual void SetDebugInfoHadFrameVariableErrors() = 0;
 
+  /// Return true if separate debug info files are supported and this function
+  /// succeeded, false otherwise.
+  ///
+  /// \param[out] d
+  ///     If this function succeeded, then this will be a dictionary that
+  ///     contains the keys "type", "symfile", and "separate-debug-info-files".
+  ///     "type" can be used to assume the structure of each object in
+  ///     "separate-debug-info-files".
+  virtual bool GetSeparateDebugInfo(StructuredData::Dictionary &d) {
+    return false;
+  };
+
   virtual lldb::TypeSP
   MakeType(lldb::user_id_t uid, ConstString name,
            std::optional<uint64_t> byte_size, SymbolContextScope *context,

lldb/source/Commands/CommandObjectTarget.cpp

@@ -52,6 +52,7 @@
 #include "lldb/Utility/FileSpec.h"
 #include "lldb/Utility/LLDBLog.h"
 #include "lldb/Utility/State.h"
+#include "lldb/Utility/StructuredData.h"
 #include "lldb/Utility/Timer.h"
 #include "lldb/lldb-enumerations.h"
 #include "lldb/lldb-private-enumerations.h"
@@ -61,6 +62,7 @@
 #include "clang/Frontend/CompilerInvocation.h"
 #include "clang/Frontend/FrontendActions.h"
 #include "llvm/ADT/ScopeExit.h"
+#include "llvm/ADT/StringRef.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/FormatAdapters.h"
 
@@ -1462,6 +1464,87 @@ static bool DumpModuleSymbolFile(Stream &strm, Module *module) {
   return false;
 }
 
+static bool GetSeparateDebugInfoList(StructuredData::Array &list,
+                                     Module *module) {
+  if (module) {
+    if (SymbolFile *symbol_file = module->GetSymbolFile(/*can_create=*/true)) {
+      StructuredData::Dictionary d;
+      if (symbol_file->GetSeparateDebugInfo(d)) {
+        list.AddItem(
+            std::make_shared<StructuredData::Dictionary>(std::move(d)));
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
+static void DumpDwoFilesTable(Stream &strm,
+                              StructuredData::Array &dwo_listings) {
+  strm.PutCString("Dwo ID             Err Dwo Path");
+  strm.EOL();
+  strm.PutCString(
+      "------------------ --- -----------------------------------------");
+  strm.EOL();
+  dwo_listings.ForEach([&strm](StructuredData::Object *dwo) {
+    StructuredData::Dictionary *dict = dwo->GetAsDictionary();
+    if (!dict)
+      return false;
+
+    uint64_t dwo_id;
+    if (dict->GetValueForKeyAsInteger("dwo_id", dwo_id))
+      strm.Printf("0x%16.16" PRIx64 " ", dwo_id);
+    else
+      strm.Printf("0x???????????????? ");
+
+    llvm::StringRef error;
+    if (dict->GetValueForKeyAsString("error", error))
+      strm << "E   " << error;
+    else {
+      llvm::StringRef resolved_dwo_path;
+      if (dict->GetValueForKeyAsString("resolved_dwo_path",
+                                       resolved_dwo_path)) {
+        strm << "    " << resolved_dwo_path;
+        if (resolved_dwo_path.ends_with(".dwp")) {
+          llvm::StringRef dwo_name;
+          if (dict->GetValueForKeyAsString("dwo_name", dwo_name))
+            strm << "(" << dwo_name << ")";
+        }
+      }
+    }
+    strm.EOL();
+    return true;
+  });
+}
+
+static void DumpOsoFilesTable(Stream &strm,
+                              StructuredData::Array &oso_listings) {
+  strm.PutCString("Mod Time           Err Oso Path");
+  strm.EOL();
+  strm.PutCString("------------------ --- ---------------------");
+  strm.EOL();
+  oso_listings.ForEach([&strm](StructuredData::Object *oso) {
+    StructuredData::Dictionary *dict = oso->GetAsDictionary();
+    if (!dict)
+      return false;
+
+    uint32_t oso_mod_time;
+    if (dict->GetValueForKeyAsInteger("oso_mod_time", oso_mod_time))
+      strm.Printf("0x%16.16" PRIx32 " ", oso_mod_time);
+
+    llvm::StringRef error;
+    if (dict->GetValueForKeyAsString("error", error))
+      strm << "E   " << error;
+    else {
+      llvm::StringRef oso_path;
+      if (dict->GetValueForKeyAsString("oso_path", oso_path))
+        strm << "    " << oso_path;
+    }
+    strm.EOL();
+    return true;
+  });
+}
+
 static void DumpAddress(ExecutionContextScope *exe_scope,
                         const Address &so_addr, bool verbose, bool all_ranges,
                         Stream &strm) {
@@ -2462,6 +2545,176 @@ class CommandObjectTargetModulesDumpLineTable
   CommandOptions m_options;
 };
 
+#pragma mark CommandObjectTargetModulesDumpSeparateDebugInfoFiles
+#define LLDB_OPTIONS_target_modules_dump_separate_debug_info
+#include "CommandOptions.inc"
+
+// Image debug separate debug info dumping command
+
+class CommandObjectTargetModulesDumpSeparateDebugInfoFiles
+    : public CommandObjectTargetModulesModuleAutoComplete {
+public:
+  CommandObjectTargetModulesDumpSeparateDebugInfoFiles(
+      CommandInterpreter &interpreter)
+      : CommandObjectTargetModulesModuleAutoComplete(
+            interpreter, "target modules dump separate-debug-info",
+            "List the separate debug info symbol files for one or more target "
+            "modules.",
+            nullptr, eCommandRequiresTarget) {}
+
+  ~CommandObjectTargetModulesDumpSeparateDebugInfoFiles() override = default;
+
+  Options *GetOptions() override { return &m_options; }
+
+  class CommandOptions : public Options {
+  public:
+    CommandOptions() = default;
+
+    ~CommandOptions() override = default;
+
+    Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
+                          ExecutionContext *execution_context) override {
+      Status error;
+      const int short_option = m_getopt_table[option_idx].val;
+
+      switch (short_option) {
+      case 'j':
+        m_json.SetCurrentValue(true);
+        m_json.SetOptionWasSet();
+        break;
+
+      default:
+        llvm_unreachable("Unimplemented option");
+      }
+      return error;
+    }
+
+    void OptionParsingStarting(ExecutionContext *execution_context) override {
+      m_json.Clear();
+    }
+
+    llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
+      return llvm::ArrayRef(g_target_modules_dump_separate_debug_info_options);
+    }
+
+    OptionValueBoolean m_json = false;
+  };
+
+protected:
+  bool DoExecute(Args &command, CommandReturnObject &result) override {
+    Target &target = GetSelectedTarget();
+    uint32_t num_dumped = 0;
+
+    uint32_t addr_byte_size = target.GetArchitecture().GetAddressByteSize();
+    result.GetOutputStream().SetAddressByteSize(addr_byte_size);
+    result.GetErrorStream().SetAddressByteSize(addr_byte_size);
+
+    StructuredData::Array separate_debug_info_lists_by_module;
+    if (command.GetArgumentCount() == 0) {
+      // Dump all sections for all modules images
+      const ModuleList &target_modules = target.GetImages();
+      std::lock_guard<std::recursive_mutex> guard(target_modules.GetMutex());
+      const size_t num_modules = target_modules.GetSize();
+      if (num_modules == 0) {
+        result.AppendError("the target has no associated executable images");
+        return false;
+      }
+      for (ModuleSP module_sp : target_modules.ModulesNoLocking()) {
+        if (INTERRUPT_REQUESTED(
+                GetDebugger(),
+                "Interrupted in dumping all "
+                "separate debug info with {0} of {1} modules dumped",
+                num_dumped, num_modules))
+          break;
+
+        if (GetSeparateDebugInfoList(separate_debug_info_lists_by_module,
+                                     module_sp.get()))
+          num_dumped++;
+      }
+    } else {
+      // Dump specified images (by basename or fullpath)
+      const char *arg_cstr;
+      for (int arg_idx = 0;
+           (arg_cstr = command.GetArgumentAtIndex(arg_idx)) != nullptr;
+           ++arg_idx) {
+        ModuleList module_list;
+        const size_t num_matches =
+            FindModulesByName(&target, arg_cstr, module_list, true);
+        if (num_matches > 0) {
+          for (size_t i = 0; i < num_matches; ++i) {
+            if (INTERRUPT_REQUESTED(GetDebugger(),
+                                    "Interrupted dumping {0} "
+                                    "of {1} requested modules",
+                                    i, num_matches))
+              break;
+            Module *module = module_list.GetModulePointerAtIndex(i);
+            if (GetSeparateDebugInfoList(separate_debug_info_lists_by_module,
+                                         module))
+              num_dumped++;
+          }
+        } else
+          result.AppendWarningWithFormat(
+              "Unable to find an image that matches '%s'.\n", arg_cstr);
+      }
+    }
+
+    if (num_dumped > 0) {
+      Stream &strm = result.GetOutputStream();
+      if (m_options.m_json) {
+        separate_debug_info_lists_by_module.Dump(strm,
+                                                 /*pretty_print=*/true);
+      } else {
+        // List the debug info files in human readable form.
+        separate_debug_info_lists_by_module.ForEach(
+            [&result, &strm](StructuredData::Object *obj) {
+              if (!obj) {
+                return false;
+              }
+
+              // Each item in `separate_debug_info_lists_by_module` should be a
+              // valid structured data dictionary.
+              StructuredData::Dictionary *separate_debug_info_list =
+                  obj->GetAsDictionary();
+              if (!separate_debug_info_list) {
+                return false;
+              }
+
+              llvm::StringRef type;
+              llvm::StringRef symfile;
+              StructuredData::Array *files;
+              assert(separate_debug_info_list->GetValueForKeyAsString("type",
+                                                                      type));
+              assert(separate_debug_info_list->GetValueForKeyAsString("symfile",
+                                                                      symfile));
+              assert(separate_debug_info_list->GetValueForKeyAsArray(
+                  "separate-debug-info-files", files));
+
+              strm << "Symbol file: " << symfile;
+              strm.EOL();
+              strm << "Type: \"" << type << "\"";
+              strm.EOL();
+              if (type == "dwo") {
+                DumpDwoFilesTable(strm, *files);
+              } else if (type == "oso") {
+                DumpOsoFilesTable(strm, *files);
+              } else {
+                result.AppendWarningWithFormat(
+                    "Found unsupported debug info type '%s'.\n",
+                    type.str().c_str());
+              }
+              return true;
+            });
+      }
+      result.SetStatus(eReturnStatusSuccessFinishResult);
+    } else {
+      result.AppendError("no matching executable images found");
+    }
+    return result.Succeeded();
+  }
+
+  CommandOptions m_options;
+};
+
 #pragma mark CommandObjectTargetModulesDump
 
 // Dump multi-word command for target modules
@@ -2475,7 +2728,8 @@ class CommandObjectTargetModulesDump : public CommandObjectMultiword {
             "Commands for dumping information about one or more target "
             "modules.",
             "target modules dump "
-            "[objfile|symtab|sections|ast|symfile|line-table|pcm-info] "
+            "[objfile|symtab|sections|ast|symfile|line-table|pcm-info|separate-"
+            "debug-info] "
             "[<file1> <file2> ...]") {
     LoadSubCommand("objfile",
                    CommandObjectSP(
@@ -2499,6 +2753,10 @@ class CommandObjectTargetModulesDump : public CommandObjectMultiword {
         "pcm-info",
         CommandObjectSP(
             new CommandObjectTargetModulesDumpClangPCMInfo(interpreter)));
+    LoadSubCommand("separate-debug-info",
+                   CommandObjectSP(
+                       new CommandObjectTargetModulesDumpSeparateDebugInfoFiles(
+                           interpreter)));
   }
 
   ~CommandObjectTargetModulesDump() override = default;

lldb/source/Commands/Options.td

@@ -8,6 +8,11 @@ let Command = "target modules dump symtab" in {
     Desc<"Do not demangle symbol names before showing them.">;
 }
 
+let Command = "target modules dump separate debug info" in {
+  def tm_json : Option<"json", "j">, Group<1>,
+  Desc<"Output the details in JSON format.">;
+}
+
 let Command = "help" in {
   def help_hide_aliases : Option<"hide-aliases", "a">,
     Desc<"Hide aliases in the command list.">;