[lldb] Add support for unique target ids

lldb/include/lldb/API/SBDebugger.h

@@ -359,6 +359,9 @@ class LLDB_API SBDebugger {
   lldb::SBTarget FindTargetWithFileAndArch(const char *filename,
                                            const char *arch);
 
+  /// Find a target with the specified unique ID
+  lldb::SBTarget FindTargetWithUniqueID(uint32_t id);
+
   /// Get the number of targets in the debugger.
   uint32_t GetNumTargets();
 

lldb/include/lldb/API/SBTarget.h

@@ -357,6 +357,8 @@ class LLDB_API SBTarget {
 
   const char *GetLabel() const;
 
+  uint32_t GetUniqueID() const;
+
   SBError SetLabel(const char *label);
 
   /// Architecture opcode byte size width accessor

lldb/include/lldb/Target/Target.h

@@ -600,6 +600,12 @@ class Target : public std::enable_shared_from_this<Target>,
 
   bool IsDummyTarget() const { return m_is_dummy_target; }
 
+  /// Get the unique ID for this target.
+  ///
+  /// \return
+  ///     The unique ID for this target, or 0 if no ID has been assigned.
+  uint32_t GetUniqueID() const { return m_target_unique_id; }
+
   const std::string &GetLabel() const { return m_label; }
 
   /// Set a label for a target.
@@ -1651,6 +1657,8 @@ class Target : public std::enable_shared_from_this<Target>,
   bool m_suppress_stop_hooks; /// Used to not run stop hooks for expressions
   bool m_is_dummy_target;
   unsigned m_next_persistent_variable_index = 0;
+  uint32_t m_target_unique_id =
+      LLDB_INVALID_TARGET_ID; /// The unique ID assigned to this target
   /// An optional \a lldb_private::Trace object containing processor trace
   /// information of this target.
   lldb::TraceSP m_trace_sp;

lldb/include/lldb/Target/TargetList.h

@@ -159,6 +159,8 @@ class TargetList : public Broadcaster {
 
   lldb::TargetSP FindTargetWithProcess(lldb_private::Process *process) const;
 
+  lldb::TargetSP FindTargetWithUniqueID(uint32_t id) const;
+
   lldb::TargetSP GetTargetSP(Target *target) const;
 
   /// Send an async interrupt to one or all processes.

lldb/include/lldb/lldb-defines.h

@@ -96,6 +96,7 @@
 #define LLDB_INVALID_QUEUE_ID 0
 #define LLDB_INVALID_CPU_ID UINT32_MAX
 #define LLDB_INVALID_WATCHPOINT_RESOURCE_ID UINT32_MAX
+#define LLDB_INVALID_TARGET_ID 0
 
 /// CPU Type definitions
 #define LLDB_ARCH_DEFAULT "systemArch"

lldb/source/API/SBDebugger.cpp

@@ -983,6 +983,16 @@ uint32_t SBDebugger::GetIndexOfTarget(lldb::SBTarget target) {
   return m_opaque_sp->GetTargetList().GetIndexOfTarget(target.GetSP());
 }
 
+SBTarget SBDebugger::FindTargetWithUniqueID(uint32_t id) {
+  LLDB_INSTRUMENT_VA(this, id);
+  SBTarget sb_target;
+  if (m_opaque_sp) {
+    // No need to lock, the target list is thread safe
+    sb_target.SetSP(m_opaque_sp->GetTargetList().FindTargetWithUniqueID(id));
+  }
+  return sb_target;
+}
+
 SBTarget SBDebugger::FindTargetWithProcessID(lldb::pid_t pid) {
   LLDB_INSTRUMENT_VA(this, pid);
 

lldb/source/API/SBTarget.cpp

@@ -1632,6 +1632,14 @@ const char *SBTarget::GetLabel() const {
   return nullptr;
 }
 
+uint32_t SBTarget::GetUniqueID() const {
+  LLDB_INSTRUMENT_VA(this);
+
+  if (TargetSP target_sp = GetSP())
+    return target_sp->GetUniqueID();
+  return LLDB_INVALID_TARGET_ID;
+}
+
 SBError SBTarget::SetLabel(const char *label) {
   LLDB_INSTRUMENT_VA(this, label);
 

lldb/source/Target/Target.cpp

@@ -139,6 +139,8 @@ struct MainExecutableInstaller {
 };
 } // namespace
 
+static uint32_t g_target_unique_id = 1;
+
 template <typename Installer>
 static Status installExecutable(const Installer &installer) {
   if (!installer.m_local_file || !installer.m_remote_file)
@@ -183,6 +185,7 @@ Target::Target(Debugger &debugger, const ArchSpec &target_arch,
       m_source_manager_up(), m_stop_hooks(), m_stop_hook_next_id(0),
       m_latest_stop_hook_id(0), m_valid(true), m_suppress_stop_hooks(false),
       m_is_dummy_target(is_dummy_target),
+      m_target_unique_id(g_target_unique_id++),
       m_frame_recognizer_manager_up(
           std::make_unique<StackFrameRecognizerManager>()) {
   SetEventName(eBroadcastBitBreakpointChanged, "breakpoint-changed");

lldb/source/Target/TargetList.cpp

@@ -428,6 +428,18 @@ TargetSP TargetList::FindTargetWithProcess(Process *process) const {
   return target_sp;
 }
 
+TargetSP TargetList::FindTargetWithUniqueID(uint32_t id) const {
+  std::lock_guard<std::recursive_mutex> guard(m_target_list_mutex);
+  auto it = llvm::find_if(m_target_list, [id](const TargetSP &item) {
+    return item->GetUniqueID() == id;
+  });
+
+  if (it != m_target_list.end())
+    return *it;
+
+  return TargetSP();
+}
+
 TargetSP TargetList::GetTargetSP(Target *target) const {
   TargetSP target_sp;
   if (!target)

lldb/test/API/python_api/debugger/TestDebuggerAPI.py

@@ -294,3 +294,106 @@ def test_version(self):
 
         self.assertEqual(instance_str, class_str)
         self.assertEqual(class_str, property_str)
+
+    def test_find_target_with_unique_id(self):
+        """Test SBDebugger.FindTargetWithUniqueID() functionality."""
+
+        # Test with invalid ID - should return invalid target
+        invalid_target = self.dbg.FindTargetWithUniqueID(999999)
+        self.assertFalse(invalid_target.IsValid())
+
+        # Test with ID 0 - should return invalid target
+        zero_target = self.dbg.FindTargetWithUniqueID(0)
+        self.assertFalse(zero_target.IsValid())
+
+        # Build a real executable and create target with it
+        self.build()
+        exe = self.getBuildArtifact("a.out")
+        target = self.dbg.CreateTarget(exe)
+        self.assertTrue(target.IsValid())
+
+        # Find the target using its unique ID
+        unique_id = target.GetUniqueID()
+        self.assertNotEqual(unique_id, 0)
+        found_target = self.dbg.FindTargetWithUniqueID(unique_id)
+        self.assertTrue(found_target.IsValid())
+        self.assertEqual(
+            self.dbg.GetIndexOfTarget(target), self.dbg.GetIndexOfTarget(found_target)
+        )
+        self.assertEqual(found_target.GetUniqueID(), unique_id)
+
+    def test_target_unique_id_uniqueness(self):
+        """Test that Target.GetUniqueID() returns unique values across multiple targets."""
+
+        # Create multiple targets and verify they all have unique IDs
+        self.build()
+        exe = self.getBuildArtifact("a.out")
+        targets = []
+        unique_ids = set()
+
+        for i in range(10):
+            target = self.dbg.CreateTarget(exe)
+            self.assertTrue(target.IsValid())
+
+            unique_id = target.GetUniqueID()
+            self.assertNotEqual(unique_id, 0)
+
+            # Verify this ID hasn't been used before
+            self.assertNotIn(
+                unique_id, unique_ids, f"Duplicate unique ID found: {unique_id}"
+            )
+
+            unique_ids.add(unique_id)
+            targets.append(target)
+
+        # Verify all targets can still be found by their IDs
+        for target in targets:
+            unique_id = target.GetUniqueID()
+            found = self.dbg.FindTargetWithUniqueID(unique_id)
+            self.assertTrue(found.IsValid())
+            self.assertEqual(found.GetUniqueID(), unique_id)
+
+    def test_target_unique_id_uniqueness_after_deletion(self):
+        """Test finding targets have unique ID after target deletion."""
+        # Create two targets
+        self.build()
+        exe = self.getBuildArtifact("a.out")
+        target1 = self.dbg.CreateTarget(exe)
+        target2 = self.dbg.CreateTarget(exe)
+        self.assertTrue(target1.IsValid())
+        self.assertTrue(target2.IsValid())
+
+        unique_id1 = target1.GetUniqueID()
+        unique_id2 = target2.GetUniqueID()
+        self.assertNotEqual(unique_id1, 0)
+        self.assertNotEqual(unique_id2, 0)
+        self.assertNotEqual(unique_id1, unique_id2)
+
+        # Verify we can find them initially
+        found_target1 = self.dbg.FindTargetWithUniqueID(unique_id1)
+        found_target2 = self.dbg.FindTargetWithUniqueID(unique_id2)
+        self.assertTrue(found_target1.IsValid())
+        self.assertTrue(found_target2.IsValid())
+        target2_index = self.dbg.GetIndexOfTarget(target2)
+
+        # Delete target 2
+        deleted = self.dbg.DeleteTarget(target2)
+        self.assertTrue(deleted)
+
+        # Try to find the deleted target - should not be found
+        not_found_target = self.dbg.FindTargetWithUniqueID(unique_id2)
+        self.assertFalse(not_found_target.IsValid())
+
+        # Create a new target
+        target3 = self.dbg.CreateTarget(exe)
+        self.assertTrue(target3.IsValid())
+        # Target list index of target3 should be the same as target2's
+        # since it was deleted, but it should have a distinct unique ID
+        target3_index = self.dbg.GetIndexOfTarget(target3)
+        unique_id3 = target3.GetUniqueID()
+        self.assertEqual(target3_index, target2_index)
+        self.assertNotEqual(unique_id3, unique_id2)
+        self.assertNotEqual(unique_id3, unique_id1)
+        # Make sure we can find the new target
+        found_target3 = self.dbg.FindTargetWithUniqueID(target3.GetUniqueID())
+        self.assertTrue(found_target3.IsValid())