deps: update V8 to 7.3.492.25

PR-URL: https://github.com/nodejs/node/pull/25852
Reviewed-By: Ujjwal Sharma <usharma1998@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Ali Ijaz Sheikh <ofrobots@google.com>

21 files changed, 912 insertions, 688 deletions

diff --git a/deps/v8/src/profiler/allocation-tracker.cc b/deps/v8/src/profiler/allocation-tracker.cc
index 51cb0eb47f..d01060543d 100644
--- a/deps/v8/src/profiler/allocation-tracker.cc
+++ b/deps/v8/src/profiler/allocation-tracker.cc
@@ -213,7 +213,7 @@ void AllocationTracker::AllocationEvent(Address addr, int size) {
   JavaScriptFrameIterator it(isolate);
   while (!it.done() && length < kMaxAllocationTraceLength) {
     JavaScriptFrame* frame = it.frame();
-    SharedFunctionInfo* shared = frame->function()->shared();
+    SharedFunctionInfo shared = frame->function()->shared();
     SnapshotObjectId id = ids_->FindOrAddEntry(
         shared->address(), shared->Size(), false);
     allocation_trace_buffer_[length++] = AddFunctionInfo(shared, id);
@@ -237,8 +237,7 @@ static uint32_t SnapshotObjectIdHash(SnapshotObjectId id) {
   return ComputeUnseededHash(static_cast<uint32_t>(id));
 }
 
-
-unsigned AllocationTracker::AddFunctionInfo(SharedFunctionInfo* shared,
+unsigned AllocationTracker::AddFunctionInfo(SharedFunctionInfo shared,
                                             SnapshotObjectId id) {
   base::HashMap::Entry* entry = id_to_function_info_index_.LookupOrInsert(
       reinterpret_cast<void*>(id), SnapshotObjectIdHash(id));
@@ -247,9 +246,9 @@ unsigned AllocationTracker::AddFunctionInfo(SharedFunctionInfo* shared,
     info->name = names_->GetName(shared->DebugName());
     info->function_id = id;
     if (shared->script()->IsScript()) {
-      Script* script = Script::cast(shared->script());
+      Script script = Script::cast(shared->script());
       if (script->name()->IsName()) {
-        Name* name = Name::cast(script->name());
+        Name name = Name::cast(script->name());
         info->script_name = names_->GetName(name);
       }
       info->script_id = script->id();
@@ -264,7 +263,6 @@ unsigned AllocationTracker::AddFunctionInfo(SharedFunctionInfo* shared,
   return static_cast<unsigned>(reinterpret_cast<intptr_t>((entry->value)));
 }
 
-
 unsigned AllocationTracker::functionInfoIndexForVMState(StateTag state) {
   if (state != OTHER) return 0;
   if (info_index_for_other_state_ == 0) {
@@ -277,20 +275,18 @@ unsigned AllocationTracker::functionInfoIndexForVMState(StateTag state) {
   return info_index_for_other_state_;
 }
 
-
-AllocationTracker::UnresolvedLocation::UnresolvedLocation(
-    Script* script, int start, FunctionInfo* info)
-    : start_position_(start),
-      info_(info) {
+AllocationTracker::UnresolvedLocation::UnresolvedLocation(Script script,
+                                                          int start,
+                                                          FunctionInfo* info)
+    : start_position_(start), info_(info) {
   script_ = script->GetIsolate()->global_handles()->Create(script);
-  GlobalHandles::MakeWeak(reinterpret_cast<Object**>(script_.location()), this,
-                          &HandleWeakScript, v8::WeakCallbackType::kParameter);
+  GlobalHandles::MakeWeak(script_.location(), this, &HandleWeakScript,
+                          v8::WeakCallbackType::kParameter);
 }
 
-
 AllocationTracker::UnresolvedLocation::~UnresolvedLocation() {
   if (!script_.is_null()) {
-    GlobalHandles::Destroy(reinterpret_cast<Object**>(script_.location()));
+    GlobalHandles::Destroy(script_.location());
   }
 }
 
@@ -306,7 +302,7 @@ void AllocationTracker::UnresolvedLocation::HandleWeakScript(
     const v8::WeakCallbackInfo<void>& data) {
   UnresolvedLocation* loc =
       reinterpret_cast<UnresolvedLocation*>(data.GetParameter());
-  GlobalHandles::Destroy(reinterpret_cast<Object**>(loc->script_.location()));
+  GlobalHandles::Destroy(loc->script_.location());
   loc->script_ = Handle<Script>::null();
 }
 
diff --git a/deps/v8/src/profiler/allocation-tracker.h b/deps/v8/src/profiler/allocation-tracker.h
index bff9a62750..5305bdbf2d 100644
--- a/deps/v8/src/profiler/allocation-tracker.h
+++ b/deps/v8/src/profiler/allocation-tracker.h
@@ -120,12 +120,12 @@ class AllocationTracker {
   AddressToTraceMap* address_to_trace() { return &address_to_trace_; }
 
  private:
-  unsigned AddFunctionInfo(SharedFunctionInfo* info, SnapshotObjectId id);
+  unsigned AddFunctionInfo(SharedFunctionInfo info, SnapshotObjectId id);
   unsigned functionInfoIndexForVMState(StateTag state);
 
   class UnresolvedLocation {
    public:
-    UnresolvedLocation(Script* script, int start, FunctionInfo* info);
+    UnresolvedLocation(Script script, int start, FunctionInfo* info);
     ~UnresolvedLocation();
     void Resolve();
 
diff --git a/deps/v8/src/profiler/circular-queue.h b/deps/v8/src/profiler/circular-queue.h
index d3df1d9f38..fcbb898571 100644
--- a/deps/v8/src/profiler/circular-queue.h
+++ b/deps/v8/src/profiler/circular-queue.h
@@ -46,7 +46,7 @@ class SamplingCircularQueue {
              // completely processed by the consumer.
   };
 
-  struct V8_ALIGNED(PROCESSOR_CACHE_LINE_SIZE) Entry {
+  struct alignas(PROCESSOR_CACHE_LINE_SIZE) Entry {
     Entry() : marker(kEmpty) {}
     T record;
     base::Atomic32 marker;
@@ -55,8 +55,8 @@ class SamplingCircularQueue {
   Entry* Next(Entry* entry);
 
   Entry buffer_[Length];
-  V8_ALIGNED(PROCESSOR_CACHE_LINE_SIZE) Entry* enqueue_pos_;
-  V8_ALIGNED(PROCESSOR_CACHE_LINE_SIZE) Entry* dequeue_pos_;
+  alignas(PROCESSOR_CACHE_LINE_SIZE) Entry* enqueue_pos_;
+  alignas(PROCESSOR_CACHE_LINE_SIZE) Entry* dequeue_pos_;
 
   DISALLOW_COPY_AND_ASSIGN(SamplingCircularQueue);
 };
diff --git a/deps/v8/src/profiler/cpu-profiler-inl.h b/deps/v8/src/profiler/cpu-profiler-inl.h
index 9274bc03c6..eb05c5be56 100644
--- a/deps/v8/src/profiler/cpu-profiler-inl.h
+++ b/deps/v8/src/profiler/cpu-profiler-inl.h
@@ -53,8 +53,7 @@ void ReportBuiltinEventRecord::UpdateCodeMap(CodeMap* code_map) {
   entry->SetBuiltinId(builtin_id);
 }
 
-
-TickSample* ProfilerEventsProcessor::StartTickSample() {
+TickSample* SamplingEventsProcessor::StartTickSample() {
   void* address = ticks_buffer_.StartEnqueue();
   if (address == nullptr) return nullptr;
   TickSampleEventRecord* evt =
@@ -62,8 +61,7 @@ TickSample* ProfilerEventsProcessor::StartTickSample() {
   return &evt->sample;
 }
 
-
-void ProfilerEventsProcessor::FinishTickSample() {
+void SamplingEventsProcessor::FinishTickSample() {
   ticks_buffer_.FinishEnqueue();
 }
 
diff --git a/deps/v8/src/profiler/cpu-profiler.cc b/deps/v8/src/profiler/cpu-profiler.cc
index 21d7c9072e..c3fba16879 100644
--- a/deps/v8/src/profiler/cpu-profiler.cc
+++ b/deps/v8/src/profiler/cpu-profiler.cc
@@ -14,7 +14,7 @@
 #include "src/deoptimizer.h"
 #include "src/frames-inl.h"
 #include "src/locked-queue-inl.h"
-#include "src/log-inl.h"
+#include "src/log.h"
 #include "src/profiler/cpu-profiler-inl.h"
 #include "src/vm-state-inl.h"
 
@@ -25,7 +25,7 @@ static const int kProfilerStackSize = 64 * KB;
 
 class CpuSampler : public sampler::Sampler {
  public:
-  CpuSampler(Isolate* isolate, ProfilerEventsProcessor* processor)
+  CpuSampler(Isolate* isolate, SamplingEventsProcessor* processor)
       : sampler::Sampler(reinterpret_cast<v8::Isolate*>(isolate)),
         processor_(processor) {}
 
@@ -42,60 +42,68 @@ class CpuSampler : public sampler::Sampler {
   }
 
  private:
-  ProfilerEventsProcessor* processor_;
+  SamplingEventsProcessor* processor_;
 };
 
 ProfilerEventsProcessor::ProfilerEventsProcessor(Isolate* isolate,
-                                                 ProfileGenerator* generator,
-                                                 base::TimeDelta period)
+                                                 ProfileGenerator* generator)
     : Thread(Thread::Options("v8:ProfEvntProc", kProfilerStackSize)),
       generator_(generator),
-      sampler_(new CpuSampler(isolate, this)),
       running_(1),
-      period_(period),
       last_code_event_id_(0),
-      last_processed_code_event_id_(0) {
-  sampler_->IncreaseProfilingDepth();
-}
+      last_processed_code_event_id_(0),
+      isolate_(isolate) {}
 
-ProfilerEventsProcessor::~ProfilerEventsProcessor() {
-  sampler_->DecreaseProfilingDepth();
+SamplingEventsProcessor::SamplingEventsProcessor(Isolate* isolate,
+                                                 ProfileGenerator* generator,
+                                                 base::TimeDelta period)
+    : ProfilerEventsProcessor(isolate, generator),
+      sampler_(new CpuSampler(isolate, this)),
+      period_(period) {
+  sampler_->Start();
 }
 
+SamplingEventsProcessor::~SamplingEventsProcessor() { sampler_->Stop(); }
+
+ProfilerEventsProcessor::~ProfilerEventsProcessor() = default;
+
 void ProfilerEventsProcessor::Enqueue(const CodeEventsContainer& event) {
   event.generic.order = ++last_code_event_id_;
   events_buffer_.Enqueue(event);
 }
 
-
-void ProfilerEventsProcessor::AddDeoptStack(Isolate* isolate, Address from,
-                                            int fp_to_sp_delta) {
+void ProfilerEventsProcessor::AddDeoptStack(Address from, int fp_to_sp_delta) {
   TickSampleEventRecord record(last_code_event_id_);
   RegisterState regs;
-  Address fp = isolate->c_entry_fp(isolate->thread_local_top());
+  Address fp = isolate_->c_entry_fp(isolate_->thread_local_top());
   regs.sp = reinterpret_cast<void*>(fp - fp_to_sp_delta);
   regs.fp = reinterpret_cast<void*>(fp);
   regs.pc = reinterpret_cast<void*>(from);
-  record.sample.Init(isolate, regs, TickSample::kSkipCEntryFrame, false, false);
+  record.sample.Init(isolate_, regs, TickSample::kSkipCEntryFrame, false,
+                     false);
   ticks_from_vm_buffer_.Enqueue(record);
 }
 
-void ProfilerEventsProcessor::AddCurrentStack(Isolate* isolate,
-                                              bool update_stats) {
+void ProfilerEventsProcessor::AddCurrentStack(bool update_stats) {
   TickSampleEventRecord record(last_code_event_id_);
   RegisterState regs;
-  StackFrameIterator it(isolate);
+  StackFrameIterator it(isolate_);
   if (!it.done()) {
     StackFrame* frame = it.frame();
     regs.sp = reinterpret_cast<void*>(frame->sp());
     regs.fp = reinterpret_cast<void*>(frame->fp());
     regs.pc = reinterpret_cast<void*>(frame->pc());
   }
-  record.sample.Init(isolate, regs, TickSample::kSkipCEntryFrame, update_stats,
+  record.sample.Init(isolate_, regs, TickSample::kSkipCEntryFrame, update_stats,
                      false);
   ticks_from_vm_buffer_.Enqueue(record);
 }
 
+void ProfilerEventsProcessor::AddSample(TickSample sample) {
+  TickSampleEventRecord record(last_code_event_id_);
+  record.sample = sample;
+  ticks_from_vm_buffer_.Enqueue(record);
+}
 
 void ProfilerEventsProcessor::StopSynchronously() {
   if (!base::Relaxed_AtomicExchange(&running_, 0)) return;
@@ -123,8 +131,30 @@ bool ProfilerEventsProcessor::ProcessCodeEvent() {
   return false;
 }
 
+void ProfilerEventsProcessor::CodeEventHandler(
+    const CodeEventsContainer& evt_rec) {
+  switch (evt_rec.generic.type) {
+    case CodeEventRecord::CODE_CREATION:
+    case CodeEventRecord::CODE_MOVE:
+    case CodeEventRecord::CODE_DISABLE_OPT:
+      Enqueue(evt_rec);
+      break;
+    case CodeEventRecord::CODE_DEOPT: {
+      const CodeDeoptEventRecord* rec = &evt_rec.CodeDeoptEventRecord_;
+      Address pc = rec->pc;
+      int fp_to_sp_delta = rec->fp_to_sp_delta;
+      Enqueue(evt_rec);
+      AddDeoptStack(pc, fp_to_sp_delta);
+      break;
+    }
+    case CodeEventRecord::NONE:
+    case CodeEventRecord::REPORT_BUILTIN:
+      UNREACHABLE();
+  }
+}
+
 ProfilerEventsProcessor::SampleProcessingResult
-    ProfilerEventsProcessor::ProcessOneSample() {
+SamplingEventsProcessor::ProcessOneSample() {
   TickSampleEventRecord record1;
   if (ticks_from_vm_buffer_.Peek(&record1) &&
       (record1.order == last_processed_code_event_id_)) {
@@ -147,8 +177,7 @@ ProfilerEventsProcessor::SampleProcessingResult
   return OneSampleProcessed;
 }
 
-
-void ProfilerEventsProcessor::Run() {
+void SamplingEventsProcessor::Run() {
   while (!!base::Relaxed_Load(&running_)) {
     base::TimeTicks nextSampleTime =
         base::TimeTicks::HighResolutionNow() + period_;
@@ -180,8 +209,8 @@ void ProfilerEventsProcessor::Run() {
       }
     }
 
-    // Schedule next sample. sampler_ is nullptr in tests.
-    if (sampler_) sampler_->DoSample();
+    // Schedule next sample.
+    sampler_->DoSample();
   }
 
   // Process remaining tick events.
@@ -193,16 +222,11 @@ void ProfilerEventsProcessor::Run() {
   } while (ProcessCodeEvent());
 }
 
-
-void* ProfilerEventsProcessor::operator new(size_t size) {
-  return AlignedAlloc(size, V8_ALIGNOF(ProfilerEventsProcessor));
-}
-
-
-void ProfilerEventsProcessor::operator delete(void* ptr) {
-  AlignedFree(ptr);
+void* SamplingEventsProcessor::operator new(size_t size) {
+  return AlignedAlloc(size, alignof(SamplingEventsProcessor));
 }
 
+void SamplingEventsProcessor::operator delete(void* ptr) { AlignedFree(ptr); }
 
 int CpuProfiler::GetProfilesCount() {
   // The count of profiles doesn't depend on a security token.
@@ -229,37 +253,17 @@ void CpuProfiler::DeleteProfile(CpuProfile* profile) {
   }
 }
 
-void CpuProfiler::CodeEventHandler(const CodeEventsContainer& evt_rec) {
-  switch (evt_rec.generic.type) {
-    case CodeEventRecord::CODE_CREATION:
-    case CodeEventRecord::CODE_MOVE:
-    case CodeEventRecord::CODE_DISABLE_OPT:
-      processor_->Enqueue(evt_rec);
-      break;
-    case CodeEventRecord::CODE_DEOPT: {
-      const CodeDeoptEventRecord* rec = &evt_rec.CodeDeoptEventRecord_;
-      Address pc = rec->pc;
-      int fp_to_sp_delta = rec->fp_to_sp_delta;
-      processor_->Enqueue(evt_rec);
-      processor_->AddDeoptStack(isolate_, pc, fp_to_sp_delta);
-      break;
-    }
-    default:
-      UNREACHABLE();
-  }
-}
-
 namespace {
 
 class CpuProfilersManager {
  public:
   void AddProfiler(Isolate* isolate, CpuProfiler* profiler) {
-    base::LockGuard<base::Mutex> lock(&mutex_);
+    base::MutexGuard lock(&mutex_);
     profilers_.emplace(isolate, profiler);
   }
 
   void RemoveProfiler(Isolate* isolate, CpuProfiler* profiler) {
-    base::LockGuard<base::Mutex> lock(&mutex_);
+    base::MutexGuard lock(&mutex_);
     auto range = profilers_.equal_range(isolate);
     for (auto it = range.first; it != range.second; ++it) {
       if (it->second != profiler) continue;
@@ -270,7 +274,7 @@ class CpuProfilersManager {
   }
 
   void CallCollectSample(Isolate* isolate) {
-    base::LockGuard<base::Mutex> lock(&mutex_);
+    base::MutexGuard lock(&mutex_);
     auto range = profilers_.equal_range(isolate);
     for (auto it = range.first; it != range.second; ++it) {
       it->second->CollectSample();
@@ -282,8 +286,7 @@ class CpuProfilersManager {
   base::Mutex mutex_;
 };
 
-base::LazyInstance<CpuProfilersManager>::type g_profilers_manager =
-    LAZY_INSTANCE_INITIALIZER;
+DEFINE_LAZY_LEAKY_OBJECT_GETTER(CpuProfilersManager, GetProfilersManager);
 
 }  // namespace
 
@@ -302,12 +305,12 @@ CpuProfiler::CpuProfiler(Isolate* isolate, CpuProfilesCollection* test_profiles,
       processor_(test_processor),
       is_profiling_(false) {
   profiles_->set_cpu_profiler(this);
-  g_profilers_manager.Pointer()->AddProfiler(isolate, this);
+  GetProfilersManager()->AddProfiler(isolate, this);
 }
 
 CpuProfiler::~CpuProfiler() {
   DCHECK(!is_profiling_);
-  g_profilers_manager.Pointer()->RemoveProfiler(isolate_, this);
+  GetProfilersManager()->RemoveProfiler(isolate_, this);
 }
 
 void CpuProfiler::set_sampling_interval(base::TimeDelta value) {
@@ -336,12 +339,12 @@ void CpuProfiler::CreateEntriesForRuntimeCallStats() {
 
 // static
 void CpuProfiler::CollectSample(Isolate* isolate) {
-  g_profilers_manager.Pointer()->CallCollectSample(isolate);
+  GetProfilersManager()->CallCollectSample(isolate);
 }
 
 void CpuProfiler::CollectSample() {
   if (processor_) {
-    processor_->AddCurrentStack(isolate_);
+    processor_->AddCurrentStack();
   }
 }
 
@@ -353,7 +356,7 @@ void CpuProfiler::StartProfiling(const char* title, bool record_samples,
   }
 }
 
-void CpuProfiler::StartProfiling(String* title, bool record_samples,
+void CpuProfiler::StartProfiling(String title, bool record_samples,
                                  ProfilingMode mode) {
   StartProfiling(profiles_->GetName(title), record_samples, mode);
   isolate_->debug()->feature_tracker()->Track(DebugFeatureTracker::kProfiler);
@@ -361,13 +364,13 @@ void CpuProfiler::StartProfiling(String* title, bool record_samples,
 
 void CpuProfiler::StartProcessorIfNotStarted() {
   if (processor_) {
-    processor_->AddCurrentStack(isolate_);
+    processor_->AddCurrentStack();
     return;
   }
   Logger* logger = isolate_->logger();
   // Disable logging when using the new implementation.
-  saved_is_logging_ = logger->is_logging_;
-  logger->is_logging_ = false;
+  saved_is_logging_ = logger->is_logging();
+  logger->set_is_logging(false);
 
   bool codemap_needs_initialization = false;
   if (!generator_) {
@@ -375,10 +378,10 @@ void CpuProfiler::StartProcessorIfNotStarted() {
     codemap_needs_initialization = true;
     CreateEntriesForRuntimeCallStats();
   }
-  processor_.reset(new ProfilerEventsProcessor(isolate_, generator_.get(),
+  processor_.reset(new SamplingEventsProcessor(isolate_, generator_.get(),
                                                sampling_interval_));
   if (!profiler_listener_) {
-    profiler_listener_.reset(new ProfilerListener(isolate_, this));
+    profiler_listener_.reset(new ProfilerListener(isolate_, processor_.get()));
   }
   logger->AddCodeEventListener(profiler_listener_.get());
   is_profiling_ = true;
@@ -394,7 +397,7 @@ void CpuProfiler::StartProcessorIfNotStarted() {
     LogBuiltins();
   }
   // Enable stack sampling.
-  processor_->AddCurrentStack(isolate_);
+  processor_->AddCurrentStack();
   processor_->StartSynchronously();
 }
 
@@ -404,7 +407,7 @@ CpuProfile* CpuProfiler::StopProfiling(const char* title) {
   return profiles_->StopProfiling(title);
 }
 
-CpuProfile* CpuProfiler::StopProfiling(String* title) {
+CpuProfile* CpuProfiler::StopProfiling(String title) {
   return StopProfiling(profiles_->GetName(title));
 }
 
@@ -420,7 +423,7 @@ void CpuProfiler::StopProcessor() {
   logger->RemoveCodeEventListener(profiler_listener_.get());
   processor_->StopSynchronously();
   processor_.reset();
-  logger->is_logging_ = saved_is_logging_;
+  logger->set_is_logging(saved_is_logging_);
 }
 
 
diff --git a/deps/v8/src/profiler/cpu-profiler.h b/deps/v8/src/profiler/cpu-profiler.h
index 6e2acdfde7..ff5975a7a7 100644
--- a/deps/v8/src/profiler/cpu-profiler.h
+++ b/deps/v8/src/profiler/cpu-profiler.h
@@ -42,7 +42,6 @@ class CodeEventRecord {
   enum Type {
     NONE = 0,
     CODE_EVENTS_TYPE_LIST(DECLARE_TYPE)
-    NUMBER_OF_TYPES
   };
 #undef DECLARE_TYPE
 
@@ -131,37 +130,27 @@ class CodeEventsContainer {
 
 // This class implements both the profile events processor thread and
 // methods called by event producers: VM and stack sampler threads.
-class ProfilerEventsProcessor : public base::Thread {
+class ProfilerEventsProcessor : public base::Thread, public CodeEventObserver {
  public:
-  ProfilerEventsProcessor(Isolate* isolate, ProfileGenerator* generator,
-                          base::TimeDelta period);
-  ~ProfilerEventsProcessor() override;
+  virtual ~ProfilerEventsProcessor();
+
+  void CodeEventHandler(const CodeEventsContainer& evt_rec) override;
 
   // Thread control.
-  void Run() override;
+  void Run() override = 0;
   void StopSynchronously();
   V8_INLINE bool running() { return !!base::Relaxed_Load(&running_); }
   void Enqueue(const CodeEventsContainer& event);
 
-  // Puts current stack into tick sample events buffer.
-  void AddCurrentStack(Isolate* isolate, bool update_stats = false);
-  void AddDeoptStack(Isolate* isolate, Address from, int fp_to_sp_delta);
+  // Puts current stack into the tick sample events buffer.
+  void AddCurrentStack(bool update_stats = false);
+  void AddDeoptStack(Address from, int fp_to_sp_delta);
+  // Add a sample into the tick sample events buffer. Used for testing.
+  void AddSample(TickSample sample);
 
-  // Tick sample events are filled directly in the buffer of the circular
-  // queue (because the structure is of fixed width, but usually not all
-  // stack frame entries are filled.) This method returns a pointer to the
-  // next record of the buffer.
-  inline TickSample* StartTickSample();
-  inline void FinishTickSample();
+ protected:
+  ProfilerEventsProcessor(Isolate* isolate, ProfileGenerator* generator);
 
-  // SamplingCircularQueue has stricter alignment requirements than a normal new
-  // can fulfil, so we need to provide our own new/delete here.
-  void* operator new(size_t size);
-  void operator delete(void* ptr);
-
-  sampler::Sampler* sampler() { return sampler_.get(); }
-
- private:
   // Called from events processing thread (Run() method.)
   bool ProcessCodeEvent();
 
@@ -170,24 +159,54 @@ class ProfilerEventsProcessor : public base::Thread {
     FoundSampleForNextCodeEvent,
     NoSamplesInQueue
   };
-  SampleProcessingResult ProcessOneSample();
+  virtual SampleProcessingResult ProcessOneSample() = 0;
 
   ProfileGenerator* generator_;
-  std::unique_ptr<sampler::Sampler> sampler_;
   base::Atomic32 running_;
-  const base::TimeDelta period_;  // Samples & code events processing period.
   LockedQueue<CodeEventsContainer> events_buffer_;
-  static const size_t kTickSampleBufferSize = 1 * MB;
+  LockedQueue<TickSampleEventRecord> ticks_from_vm_buffer_;
+  std::atomic<unsigned> last_code_event_id_;
+  unsigned last_processed_code_event_id_;
+  Isolate* isolate_;
+};
+
+class SamplingEventsProcessor : public ProfilerEventsProcessor {
+ public:
+  SamplingEventsProcessor(Isolate* isolate, ProfileGenerator* generator,
+                          base::TimeDelta period);
+  ~SamplingEventsProcessor() override;
+
+  // SamplingCircularQueue has stricter alignment requirements than a normal new
+  // can fulfil, so we need to provide our own new/delete here.
+  void* operator new(size_t size);
+  void operator delete(void* ptr);
+
+  void Run() override;
+
+  // Tick sample events are filled directly in the buffer of the circular
+  // queue (because the structure is of fixed width, but usually not all
+  // stack frame entries are filled.) This method returns a pointer to the
+  // next record of the buffer.
+  // These methods are not thread-safe and should only ever be called by one
+  // producer (from CpuSampler::SampleStack()). For testing, use AddSample.
+  inline TickSample* StartTickSample();
+  inline void FinishTickSample();
+
+  sampler::Sampler* sampler() { return sampler_.get(); }
+
+ private:
+  SampleProcessingResult ProcessOneSample() override;
+
+  static const size_t kTickSampleBufferSize = 512 * KB;
   static const size_t kTickSampleQueueLength =
       kTickSampleBufferSize / sizeof(TickSampleEventRecord);
   SamplingCircularQueue<TickSampleEventRecord,
                         kTickSampleQueueLength> ticks_buffer_;
-  LockedQueue<TickSampleEventRecord> ticks_from_vm_buffer_;
-  std::atomic<unsigned> last_code_event_id_;
-  unsigned last_processed_code_event_id_;
+  std::unique_ptr<sampler::Sampler> sampler_;
+  const base::TimeDelta period_;  // Samples & code events processing period.
 };
 
-class CpuProfiler : public CodeEventObserver {
+class CpuProfiler {
  public:
   explicit CpuProfiler(Isolate* isolate);
 
@@ -195,7 +214,7 @@ class CpuProfiler : public CodeEventObserver {
               ProfileGenerator* test_generator,
               ProfilerEventsProcessor* test_processor);
 
-  ~CpuProfiler() override;
+  ~CpuProfiler();
 
   static void CollectSample(Isolate* isolate);
 
@@ -205,16 +224,14 @@ class CpuProfiler : public CodeEventObserver {
   void CollectSample();
   void StartProfiling(const char* title, bool record_samples = false,
                       ProfilingMode mode = ProfilingMode::kLeafNodeLineNumbers);
-  void StartProfiling(String* title, bool record_samples, ProfilingMode mode);
+  void StartProfiling(String title, bool record_samples, ProfilingMode mode);
   CpuProfile* StopProfiling(const char* title);
-  CpuProfile* StopProfiling(String* title);
+  CpuProfile* StopProfiling(String title);
   int GetProfilesCount();
   CpuProfile* GetProfile(int index);
   void DeleteAllProfiles();
   void DeleteProfile(CpuProfile* profile);
 
-  void CodeEventHandler(const CodeEventsContainer& evt_rec) override;
-
   bool is_profiling() const { return is_profiling_; }
 
   ProfileGenerator* generator() const { return generator_.get(); }
diff --git a/deps/v8/src/profiler/heap-profiler.cc b/deps/v8/src/profiler/heap-profiler.cc
index 58a8f3851f..495baf9b34 100644
--- a/deps/v8/src/profiler/heap-profiler.cc
+++ b/deps/v8/src/profiler/heap-profiler.cc
@@ -52,12 +52,10 @@ void HeapProfiler::DefineWrapperClass(
   wrapper_callbacks_[class_id] = callback;
 }
 
-
 v8::RetainedObjectInfo* HeapProfiler::ExecuteWrapperClassCallback(
-    uint16_t class_id, Object** wrapper) {
+    uint16_t class_id, Handle<Object> wrapper) {
   if (wrapper_callbacks_.size() <= class_id) return nullptr;
-  return wrapper_callbacks_[class_id](
-      class_id, Utils::ToLocal(Handle<Object>(wrapper)));
+  return wrapper_callbacks_[class_id](class_id, Utils::ToLocal(wrapper));
 }
 
 void HeapProfiler::SetGetRetainerInfosCallback(
@@ -185,7 +183,7 @@ SnapshotObjectId HeapProfiler::GetSnapshotObjectId(Handle<Object> obj) {
 }
 
 void HeapProfiler::ObjectMoveEvent(Address from, Address to, int size) {
-  base::LockGuard<base::Mutex> guard(&profiler_mutex_);
+  base::MutexGuard guard(&profiler_mutex_);
   bool known_object = ids_->MoveObject(from, to, size);
   if (!known_object && allocation_tracker_) {
     allocation_tracker_->address_to_trace()->MoveObject(from, to, size);
@@ -205,18 +203,18 @@ void HeapProfiler::UpdateObjectSizeEvent(Address addr, int size) {
 }
 
 Handle<HeapObject> HeapProfiler::FindHeapObjectById(SnapshotObjectId id) {
-  HeapObject* object = nullptr;
+  HeapObject object;
   HeapIterator iterator(heap(), HeapIterator::kFilterUnreachable);
   // Make sure that object with the given id is still reachable.
-  for (HeapObject* obj = iterator.next(); obj != nullptr;
+  for (HeapObject obj = iterator.next(); !obj.is_null();
        obj = iterator.next()) {
     if (ids_->FindEntry(obj->address()) == id) {
-      DCHECK_NULL(object);
+      DCHECK(object.is_null());
       object = obj;
       // Can't break -- kFilterUnreachable requires full heap traversal.
     }
   }
-  return object != nullptr ? Handle<HeapObject>(object, isolate())
+  return !object.is_null() ? Handle<HeapObject>(object, isolate())
                            : Handle<HeapObject>();
 }
 
@@ -238,8 +236,8 @@ void HeapProfiler::QueryObjects(Handle<Context> context,
   // collect all garbage first.
   heap()->CollectAllAvailableGarbage(GarbageCollectionReason::kHeapProfiler);
   HeapIterator heap_iterator(heap());
-  HeapObject* heap_obj;
-  while ((heap_obj = heap_iterator.next()) != nullptr) {
+  for (HeapObject heap_obj = heap_iterator.next(); !heap_obj.is_null();
+       heap_obj = heap_iterator.next()) {
     if (!heap_obj->IsJSObject() || heap_obj->IsExternal(isolate())) continue;
     v8::Local<v8::Object> v8_obj(
         Utils::ToLocal(handle(JSObject::cast(heap_obj), isolate())));
diff --git a/deps/v8/src/profiler/heap-profiler.h b/deps/v8/src/profiler/heap-profiler.h
index 1e3527765e..efeb8f769b 100644
--- a/deps/v8/src/profiler/heap-profiler.h
+++ b/deps/v8/src/profiler/heap-profiler.h
@@ -65,7 +65,7 @@ class HeapProfiler : public HeapObjectAllocationTracker {
       uint16_t class_id, v8::HeapProfiler::WrapperInfoCallback callback);
 
   v8::RetainedObjectInfo* ExecuteWrapperClassCallback(uint16_t class_id,
-                                                      Object** wrapper);
+                                                      Handle<Object> wrapper);
 
   void SetGetRetainerInfosCallback(
       v8::HeapProfiler::GetRetainerInfosCallback callback);
diff --git a/deps/v8/src/profiler/heap-snapshot-generator.cc b/deps/v8/src/profiler/heap-snapshot-generator.cc
index 57f620f4ec..17daea1964 100644
--- a/deps/v8/src/profiler/heap-snapshot-generator.cc
+++ b/deps/v8/src/profiler/heap-snapshot-generator.cc
@@ -7,7 +7,7 @@
 #include <utility>
 
 #include "src/api-inl.h"
-#include "src/code-stubs.h"
+#include "src/assembler-inl.h"
 #include "src/conversions.h"
 #include "src/debug/debug.h"
 #include "src/global-handles.h"
@@ -15,6 +15,8 @@
 #include "src/objects-body-descriptors.h"
 #include "src/objects-inl.h"
 #include "src/objects/api-callbacks.h"
+#include "src/objects/cell-inl.h"
+#include "src/objects/feedback-cell-inl.h"
 #include "src/objects/hash-table-inl.h"
 #include "src/objects/js-array-buffer-inl.h"
 #include "src/objects/js-array-inl.h"
@@ -23,6 +25,8 @@
 #include "src/objects/js-promise-inl.h"
 #include "src/objects/js-regexp-inl.h"
 #include "src/objects/literal-objects-inl.h"
+#include "src/objects/slots-inl.h"
+#include "src/objects/struct-inl.h"
 #include "src/profiler/allocation-tracker.h"
 #include "src/profiler/heap-profiler.h"
 #include "src/profiler/heap-snapshot-generator-inl.h"
@@ -177,10 +181,10 @@ const char* HeapEntry::TypeAsString() {
 HeapSnapshot::HeapSnapshot(HeapProfiler* profiler) : profiler_(profiler) {
   // It is very important to keep objects that form a heap snapshot
   // as small as possible. Check assumptions about data structure sizes.
-  STATIC_ASSERT((kPointerSize == 4 && sizeof(HeapGraphEdge) == 12) ||
-                (kPointerSize == 8 && sizeof(HeapGraphEdge) == 24));
-  STATIC_ASSERT((kPointerSize == 4 && sizeof(HeapEntry) == 28) ||
-                (kPointerSize == 8 && sizeof(HeapEntry) == 40));
+  STATIC_ASSERT((kTaggedSize == 4 && sizeof(HeapGraphEdge) == 12) ||
+                (kTaggedSize == 8 && sizeof(HeapGraphEdge) == 24));
+  STATIC_ASSERT((kTaggedSize == 4 && sizeof(HeapEntry) == 28) ||
+                (kTaggedSize == 8 && sizeof(HeapEntry) == 40));
   memset(&gc_subroot_entries_, 0, sizeof(gc_subroot_entries_));
 }
 
@@ -389,7 +393,7 @@ void HeapObjectsMap::UpdateHeapObjectsMap() {
   heap_->PreciseCollectAllGarbage(Heap::kNoGCFlags,
                                   GarbageCollectionReason::kHeapProfiler);
   HeapIterator iterator(heap_);
-  for (HeapObject* obj = iterator.next(); obj != nullptr;
+  for (HeapObject obj = iterator.next(); !obj.is_null();
        obj = iterator.next()) {
     FindOrAddEntry(obj->address(), obj->Size());
     if (FLAG_heap_profiler_trace_objects) {
@@ -511,31 +515,32 @@ V8HeapExplorer::V8HeapExplorer(HeapSnapshot* snapshot,
       global_object_name_resolver_(resolver) {}
 
 HeapEntry* V8HeapExplorer::AllocateEntry(HeapThing ptr) {
-  return AddEntry(reinterpret_cast<HeapObject*>(ptr));
+  return AddEntry(HeapObject::cast(Object(reinterpret_cast<Address>(ptr))));
 }
 
-void V8HeapExplorer::ExtractLocation(HeapEntry* entry, HeapObject* object) {
+void V8HeapExplorer::ExtractLocation(HeapEntry* entry, HeapObject object) {
   if (object->IsJSFunction()) {
-    JSFunction* func = JSFunction::cast(object);
+    JSFunction func = JSFunction::cast(object);
     ExtractLocationForJSFunction(entry, func);
 
   } else if (object->IsJSGeneratorObject()) {
-    JSGeneratorObject* gen = JSGeneratorObject::cast(object);
+    JSGeneratorObject gen = JSGeneratorObject::cast(object);
     ExtractLocationForJSFunction(entry, gen->function());
 
   } else if (object->IsJSObject()) {
-    JSObject* obj = JSObject::cast(object);
-    JSFunction* maybe_constructor = GetConstructor(obj);
+    JSObject obj = JSObject::cast(object);
+    JSFunction maybe_constructor = GetConstructor(obj);
 
-    if (maybe_constructor)
+    if (!maybe_constructor.is_null()) {
       ExtractLocationForJSFunction(entry, maybe_constructor);
+    }
   }
 }
 
 void V8HeapExplorer::ExtractLocationForJSFunction(HeapEntry* entry,
-                                                  JSFunction* func) {
+                                                  JSFunction func) {
   if (!func->shared()->script()->IsScript()) return;
-  Script* script = Script::cast(func->shared()->script());
+  Script script = Script::cast(func->shared()->script());
   int scriptId = script->id();
   int start = func->shared()->StartPosition();
   int line = script->GetLineNumber(start);
@@ -543,16 +548,16 @@ void V8HeapExplorer::ExtractLocationForJSFunction(HeapEntry* entry,
   snapshot_->AddLocation(entry, scriptId, line, col);
 }
 
-HeapEntry* V8HeapExplorer::AddEntry(HeapObject* object) {
+HeapEntry* V8HeapExplorer::AddEntry(HeapObject object) {
   if (object->IsJSFunction()) {
-    JSFunction* func = JSFunction::cast(object);
-    SharedFunctionInfo* shared = func->shared();
+    JSFunction func = JSFunction::cast(object);
+    SharedFunctionInfo shared = func->shared();
     const char* name = names_->GetName(shared->Name());
     return AddEntry(object, HeapEntry::kClosure, name);
   } else if (object->IsJSBoundFunction()) {
     return AddEntry(object, HeapEntry::kClosure, "native_bind");
   } else if (object->IsJSRegExp()) {
-    JSRegExp* re = JSRegExp::cast(object);
+    JSRegExp re = JSRegExp::cast(object);
     return AddEntry(object,
                     HeapEntry::kRegExp,
                     names_->GetName(re->Pattern()));
@@ -567,7 +572,7 @@ HeapEntry* V8HeapExplorer::AddEntry(HeapObject* object) {
     }
     return AddEntry(object, HeapEntry::kObject, name);
   } else if (object->IsString()) {
-    String* string = String::cast(object);
+    String string = String::cast(object);
     if (string->IsConsString()) {
       return AddEntry(object, HeapEntry::kConsString, "(concatenated string)");
     } else if (string->IsSlicedString()) {
@@ -586,10 +591,10 @@ HeapEntry* V8HeapExplorer::AddEntry(HeapObject* object) {
   } else if (object->IsCode()) {
     return AddEntry(object, HeapEntry::kCode, "");
   } else if (object->IsSharedFunctionInfo()) {
-    String* name = SharedFunctionInfo::cast(object)->Name();
+    String name = SharedFunctionInfo::cast(object)->Name();
     return AddEntry(object, HeapEntry::kCode, names_->GetName(name));
   } else if (object->IsScript()) {
-    Object* name = Script::cast(object)->name();
+    Object name = Script::cast(object)->name();
     return AddEntry(
         object, HeapEntry::kCode,
         name->IsString() ? names_->GetName(String::cast(name)) : "");
@@ -606,8 +611,7 @@ HeapEntry* V8HeapExplorer::AddEntry(HeapObject* object) {
   return AddEntry(object, HeapEntry::kHidden, GetSystemEntryName(object));
 }
 
-HeapEntry* V8HeapExplorer::AddEntry(HeapObject* object,
-                                    HeapEntry::Type type,
+HeapEntry* V8HeapExplorer::AddEntry(HeapObject object, HeapEntry::Type type,
                                     const char* name) {
   return AddEntry(object->address(), type, name, object->Size());
 }
@@ -627,7 +631,7 @@ HeapEntry* V8HeapExplorer::AddEntry(Address address,
   return snapshot_->AddEntry(type, name, object_id, size, trace_node_id);
 }
 
-const char* V8HeapExplorer::GetSystemEntryName(HeapObject* object) {
+const char* V8HeapExplorer::GetSystemEntryName(HeapObject object) {
   switch (object->map()->instance_type()) {
     case MAP_TYPE:
       switch (Map::cast(object)->instance_type()) {
@@ -655,56 +659,72 @@ const char* V8HeapExplorer::GetSystemEntryName(HeapObject* object) {
 int V8HeapExplorer::EstimateObjectsCount() {
   HeapIterator it(heap_, HeapIterator::kFilterUnreachable);
   int objects_count = 0;
-  while (it.next()) ++objects_count;
+  while (!it.next().is_null()) ++objects_count;
   return objects_count;
 }
 
 class IndexedReferencesExtractor : public ObjectVisitor {
  public:
-  IndexedReferencesExtractor(V8HeapExplorer* generator, HeapObject* parent_obj,
+  IndexedReferencesExtractor(V8HeapExplorer* generator, HeapObject parent_obj,
                              HeapEntry* parent)
       : generator_(generator),
         parent_obj_(parent_obj),
-        parent_start_(HeapObject::RawField(parent_obj_, 0)),
-        parent_end_(HeapObject::RawField(parent_obj_, parent_obj_->Size())),
-        parent_(parent) {}
-  void VisitPointers(HeapObject* host, Object** start, Object** end) override {
-    VisitPointers(host, reinterpret_cast<MaybeObject**>(start),
-                  reinterpret_cast<MaybeObject**>(end));
-  }
-  void VisitPointers(HeapObject* host, MaybeObject** start,
-                     MaybeObject** end) override {
-    int next_index = 0;
-    for (MaybeObject** p = start; p < end; p++) {
-      int index = static_cast<int>(reinterpret_cast<Object**>(p) -
-                                   HeapObject::RawField(parent_obj_, 0));
-      ++next_index;
-      // |p| could be outside of the object, e.g., while visiting RelocInfo of
-      // code objects.
-      if (reinterpret_cast<Object**>(p) >= parent_start_ &&
-          reinterpret_cast<Object**>(p) < parent_end_ &&
-          generator_->visited_fields_[index]) {
-        generator_->visited_fields_[index] = false;
+        parent_start_(HeapObject::RawMaybeWeakField(parent_obj_, 0)),
+        parent_end_(
+            HeapObject::RawMaybeWeakField(parent_obj_, parent_obj_->Size())),
+        parent_(parent),
+        next_index_(0) {}
+  void VisitPointers(HeapObject host, ObjectSlot start,
+                     ObjectSlot end) override {
+    VisitPointers(host, MaybeObjectSlot(start), MaybeObjectSlot(end));
+  }
+  void VisitPointers(HeapObject host, MaybeObjectSlot start,
+                     MaybeObjectSlot end) override {
+    // [start,end) must be a sub-region of [parent_start_, parent_end), i.e.
+    // all the slots must point inside the object.
+    CHECK_LE(parent_start_, start);
+    CHECK_LE(end, parent_end_);
+    for (MaybeObjectSlot p = start; p < end; ++p) {
+      int field_index = static_cast<int>(p - parent_start_);
+      if (generator_->visited_fields_[field_index]) {
+        generator_->visited_fields_[field_index] = false;
         continue;
       }
-      HeapObject* heap_object;
-      if ((*p)->GetHeapObjectIfWeak(&heap_object) ||
-          (*p)->GetHeapObjectIfStrong(&heap_object)) {
-        generator_->SetHiddenReference(parent_obj_, parent_, next_index,
-                                       heap_object, index * kPointerSize);
+      HeapObject heap_object;
+      if ((*p)->GetHeapObject(&heap_object)) {
+        VisitHeapObjectImpl(heap_object, field_index);
       }
     }
   }
 
+  void VisitCodeTarget(Code host, RelocInfo* rinfo) override {
+    Code target = Code::GetCodeFromTargetAddress(rinfo->target_address());
+    VisitHeapObjectImpl(target, -1);
+  }
+
+  void VisitEmbeddedPointer(Code host, RelocInfo* rinfo) override {
+    VisitHeapObjectImpl(rinfo->target_object(), -1);
+  }
+
  private:
+  V8_INLINE void VisitHeapObjectImpl(HeapObject heap_object, int field_index) {
+    DCHECK_LE(-1, field_index);
+    // The last parameter {field_offset} is only used to check some well-known
+    // skipped references, so passing -1 * kTaggedSize for objects embedded
+    // into code is fine.
+    generator_->SetHiddenReference(parent_obj_, parent_, next_index_++,
+                                   heap_object, field_index * kTaggedSize);
+  }
+
   V8HeapExplorer* generator_;
-  HeapObject* parent_obj_;
-  Object** parent_start_;
-  Object** parent_end_;
+  HeapObject parent_obj_;
+  MaybeObjectSlot parent_start_;
+  MaybeObjectSlot parent_end_;
   HeapEntry* parent_;
+  int next_index_;
 };
 
-void V8HeapExplorer::ExtractReferences(HeapEntry* entry, HeapObject* obj) {
+void V8HeapExplorer::ExtractReferences(HeapEntry* entry, HeapObject obj) {
   if (obj->IsJSGlobalProxy()) {
     ExtractJSGlobalProxyReferences(entry, JSGlobalProxy::cast(obj));
   } else if (obj->IsJSArrayBuffer()) {
@@ -753,6 +773,8 @@ void V8HeapExplorer::ExtractReferences(HeapEntry* entry, HeapObject* obj) {
         entry, ArrayBoilerplateDescription::cast(obj));
   } else if (obj->IsFeedbackVector()) {
     ExtractFeedbackVectorReferences(entry, FeedbackVector::cast(obj));
+  } else if (obj->IsDescriptorArray()) {
+    ExtractDescriptorArrayReferences(entry, DescriptorArray::cast(obj));
   } else if (obj->IsWeakFixedArray()) {
     ExtractWeakArrayReferences(WeakFixedArray::kHeaderSize, entry,
                                WeakFixedArray::cast(obj));
@@ -769,14 +791,14 @@ void V8HeapExplorer::ExtractReferences(HeapEntry* entry, HeapObject* obj) {
 }
 
 void V8HeapExplorer::ExtractJSGlobalProxyReferences(HeapEntry* entry,
-                                                    JSGlobalProxy* proxy) {
+                                                    JSGlobalProxy proxy) {
   SetInternalReference(entry, "native_context", proxy->native_context(),
                        JSGlobalProxy::kNativeContextOffset);
 }
 
 void V8HeapExplorer::ExtractJSObjectReferences(HeapEntry* entry,
-                                               JSObject* js_obj) {
-  HeapObject* obj = js_obj;
+                                               JSObject js_obj) {
+  HeapObject obj = js_obj;
   ExtractPropertyReferences(js_obj, entry);
   ExtractElementReferences(js_obj, entry);
   ExtractInternalReferences(js_obj, entry);
@@ -784,7 +806,7 @@ void V8HeapExplorer::ExtractJSObjectReferences(HeapEntry* entry,
   ReadOnlyRoots roots(heap_);
   SetPropertyReference(entry, roots.proto_string(), iter.GetCurrent());
   if (obj->IsJSBoundFunction()) {
-    JSBoundFunction* js_fun = JSBoundFunction::cast(obj);
+    JSBoundFunction js_fun = JSBoundFunction::cast(obj);
     TagObject(js_fun->bound_arguments(), "(bound arguments)");
     SetInternalReference(entry, "bindings", js_fun->bound_arguments(),
                          JSBoundFunction::kBoundArgumentsOffset);
@@ -793,15 +815,15 @@ void V8HeapExplorer::ExtractJSObjectReferences(HeapEntry* entry,
     SetInternalReference(entry, "bound_function",
                          js_fun->bound_target_function(),
                          JSBoundFunction::kBoundTargetFunctionOffset);
-    FixedArray* bindings = js_fun->bound_arguments();
+    FixedArray bindings = js_fun->bound_arguments();
     for (int i = 0; i < bindings->length(); i++) {
       const char* reference_name = names_->GetFormatted("bound_argument_%d", i);
       SetNativeBindReference(entry, reference_name, bindings->get(i));
     }
   } else if (obj->IsJSFunction()) {
-    JSFunction* js_fun = JSFunction::cast(js_obj);
+    JSFunction js_fun = JSFunction::cast(js_obj);
     if (js_fun->has_prototype_slot()) {
-      Object* proto_or_map = js_fun->prototype_or_initial_map();
+      Object proto_or_map = js_fun->prototype_or_initial_map();
       if (!proto_or_map->IsTheHole(heap_->isolate())) {
         if (!proto_or_map->IsMap()) {
           SetPropertyReference(entry, roots.prototype_string(), proto_or_map,
@@ -815,9 +837,9 @@ void V8HeapExplorer::ExtractJSObjectReferences(HeapEntry* entry,
         }
       }
     }
-    SharedFunctionInfo* shared_info = js_fun->shared();
-    TagObject(js_fun->feedback_cell(), "(function feedback cell)");
-    SetInternalReference(entry, "feedback_cell", js_fun->feedback_cell(),
+    SharedFunctionInfo shared_info = js_fun->shared();
+    TagObject(js_fun->raw_feedback_cell(), "(function feedback cell)");
+    SetInternalReference(entry, "feedback_cell", js_fun->raw_feedback_cell(),
                          JSFunction::kFeedbackCellOffset);
     TagObject(shared_info, "(shared function info)");
     SetInternalReference(entry, "shared", shared_info,
@@ -825,19 +847,18 @@ void V8HeapExplorer::ExtractJSObjectReferences(HeapEntry* entry,
     TagObject(js_fun->context(), "(context)");
     SetInternalReference(entry, "context", js_fun->context(),
                          JSFunction::kContextOffset);
-    TagCodeObject(js_fun->code());
     SetInternalReference(entry, "code", js_fun->code(),
                          JSFunction::kCodeOffset);
   } else if (obj->IsJSGlobalObject()) {
-    JSGlobalObject* global_obj = JSGlobalObject::cast(obj);
+    JSGlobalObject global_obj = JSGlobalObject::cast(obj);
     SetInternalReference(entry, "native_context", global_obj->native_context(),
                          JSGlobalObject::kNativeContextOffset);
     SetInternalReference(entry, "global_proxy", global_obj->global_proxy(),
                          JSGlobalObject::kGlobalProxyOffset);
     STATIC_ASSERT(JSGlobalObject::kSize - JSObject::kHeaderSize ==
-                  2 * kPointerSize);
+                  2 * kTaggedSize);
   } else if (obj->IsJSArrayBufferView()) {
-    JSArrayBufferView* view = JSArrayBufferView::cast(obj);
+    JSArrayBufferView view = JSArrayBufferView::cast(obj);
     SetInternalReference(entry, "buffer", view->buffer(),
                          JSArrayBufferView::kBufferOffset);
   }
@@ -851,47 +872,47 @@ void V8HeapExplorer::ExtractJSObjectReferences(HeapEntry* entry,
                        JSObject::kElementsOffset);
 }
 
-void V8HeapExplorer::ExtractStringReferences(HeapEntry* entry, String* string) {
+void V8HeapExplorer::ExtractStringReferences(HeapEntry* entry, String string) {
   if (string->IsConsString()) {
-    ConsString* cs = ConsString::cast(string);
+    ConsString cs = ConsString::cast(string);
     SetInternalReference(entry, "first", cs->first(), ConsString::kFirstOffset);
     SetInternalReference(entry, "second", cs->second(),
                          ConsString::kSecondOffset);
   } else if (string->IsSlicedString()) {
-    SlicedString* ss = SlicedString::cast(string);
+    SlicedString ss = SlicedString::cast(string);
     SetInternalReference(entry, "parent", ss->parent(),
                          SlicedString::kParentOffset);
   } else if (string->IsThinString()) {
-    ThinString* ts = ThinString::cast(string);
+    ThinString ts = ThinString::cast(string);
     SetInternalReference(entry, "actual", ts->actual(),
                          ThinString::kActualOffset);
   }
 }
 
-void V8HeapExplorer::ExtractSymbolReferences(HeapEntry* entry, Symbol* symbol) {
+void V8HeapExplorer::ExtractSymbolReferences(HeapEntry* entry, Symbol symbol) {
   SetInternalReference(entry, "name", symbol->name(), Symbol::kNameOffset);
 }
 
 void V8HeapExplorer::ExtractJSCollectionReferences(HeapEntry* entry,
-                                                   JSCollection* collection) {
+                                                   JSCollection collection) {
   SetInternalReference(entry, "table", collection->table(),
                        JSCollection::kTableOffset);
 }
 
 void V8HeapExplorer::ExtractJSWeakCollectionReferences(HeapEntry* entry,
-                                                       JSWeakCollection* obj) {
+                                                       JSWeakCollection obj) {
   SetInternalReference(entry, "table", obj->table(),
                        JSWeakCollection::kTableOffset);
 }
 
 void V8HeapExplorer::ExtractEphemeronHashTableReferences(
-    HeapEntry* entry, EphemeronHashTable* table) {
+    HeapEntry* entry, EphemeronHashTable table) {
   for (int i = 0, capacity = table->Capacity(); i < capacity; ++i) {
     int key_index = EphemeronHashTable::EntryToIndex(i) +
                     EphemeronHashTable::kEntryKeyIndex;
     int value_index = EphemeronHashTable::EntryToValueIndex(i);
-    Object* key = table->get(key_index);
-    Object* value = table->get(value_index);
+    Object key = table->get(key_index);
+    Object value = table->get(value_index);
     SetWeakReference(entry, key_index, key,
                      table->OffsetOfElementAt(key_index));
     SetWeakReference(entry, value_index, value,
@@ -916,23 +937,23 @@ static const struct {
 } native_context_names[] = {
 #define CONTEXT_FIELD_INDEX_NAME(index, _, name) {Context::index, #name},
     NATIVE_CONTEXT_FIELDS(CONTEXT_FIELD_INDEX_NAME)
-#undef CONTEXT_FIELD_INDEX
+#undef CONTEXT_FIELD_INDEX_NAME
 };
 
 void V8HeapExplorer::ExtractContextReferences(HeapEntry* entry,
-                                              Context* context) {
+                                              Context context) {
   if (!context->IsNativeContext() && context->is_declaration_context()) {
-    ScopeInfo* scope_info = context->scope_info();
+    ScopeInfo scope_info = context->scope_info();
     // Add context allocated locals.
     int context_locals = scope_info->ContextLocalCount();
     for (int i = 0; i < context_locals; ++i) {
-      String* local_name = scope_info->ContextLocalName(i);
+      String local_name = scope_info->ContextLocalName(i);
       int idx = Context::MIN_CONTEXT_SLOTS + i;
       SetContextReference(entry, local_name, context->get(idx),
                           Context::OffsetOfElementAt(idx));
     }
     if (scope_info->HasFunctionName()) {
-      String* name = String::cast(scope_info->FunctionName());
+      String name = String::cast(scope_info->FunctionName());
       int idx = scope_info->FunctionContextSlotIndex(name);
       if (idx >= 0) {
         SetContextReference(entry, name, context->get(idx),
@@ -979,9 +1000,9 @@ void V8HeapExplorer::ExtractContextReferences(HeapEntry* entry,
   }
 }
 
-void V8HeapExplorer::ExtractMapReferences(HeapEntry* entry, Map* map) {
-  MaybeObject* maybe_raw_transitions_or_prototype_info = map->raw_transitions();
-  HeapObject* raw_transitions_or_prototype_info;
+void V8HeapExplorer::ExtractMapReferences(HeapEntry* entry, Map map) {
+  MaybeObject maybe_raw_transitions_or_prototype_info = map->raw_transitions();
+  HeapObject raw_transitions_or_prototype_info;
   if (maybe_raw_transitions_or_prototype_info->GetHeapObjectIfWeak(
           &raw_transitions_or_prototype_info)) {
     DCHECK(raw_transitions_or_prototype_info->IsMap());
@@ -990,7 +1011,7 @@ void V8HeapExplorer::ExtractMapReferences(HeapEntry* entry, Map* map) {
   } else if (maybe_raw_transitions_or_prototype_info->GetHeapObjectIfStrong(
                  &raw_transitions_or_prototype_info)) {
     if (raw_transitions_or_prototype_info->IsTransitionArray()) {
-      TransitionArray* transitions =
+      TransitionArray transitions =
           TransitionArray::cast(raw_transitions_or_prototype_info);
       if (map->CanTransition() && transitions->HasPrototypeTransitions()) {
         TagObject(transitions->GetPrototypeTransitions(),
@@ -1012,7 +1033,7 @@ void V8HeapExplorer::ExtractMapReferences(HeapEntry* entry, Map* map) {
                            Map::kTransitionsOrPrototypeInfoOffset);
     }
   }
-  DescriptorArray* descriptors = map->instance_descriptors();
+  DescriptorArray descriptors = map->instance_descriptors();
   TagObject(descriptors, "(map descriptors)");
   SetInternalReference(entry, "descriptors", descriptors,
                        Map::kDescriptorsOffset);
@@ -1022,7 +1043,7 @@ void V8HeapExplorer::ExtractMapReferences(HeapEntry* entry, Map* map) {
     SetInternalReference(entry, "layout_descriptor", map->layout_descriptor(),
                          Map::kLayoutDescriptorOffset);
   }
-  Object* constructor_or_backpointer = map->constructor_or_backpointer();
+  Object constructor_or_backpointer = map->constructor_or_backpointer();
   if (constructor_or_backpointer->IsMap()) {
     TagObject(constructor_or_backpointer, "(back pointer)");
     SetInternalReference(entry, "back_pointer", constructor_or_backpointer,
@@ -1042,8 +1063,8 @@ void V8HeapExplorer::ExtractMapReferences(HeapEntry* entry, Map* map) {
 }
 
 void V8HeapExplorer::ExtractSharedFunctionInfoReferences(
-    HeapEntry* entry, SharedFunctionInfo* shared) {
-  String* shared_name = shared->DebugName();
+    HeapEntry* entry, SharedFunctionInfo shared) {
+  String shared_name = shared->DebugName();
   const char* name = nullptr;
   if (shared_name != ReadOnlyRoots(heap_).empty_string()) {
     name = names_->GetName(shared_name);
@@ -1071,7 +1092,7 @@ void V8HeapExplorer::ExtractSharedFunctionInfoReferences(
       SharedFunctionInfo::kOuterScopeInfoOrFeedbackMetadataOffset);
 }
 
-void V8HeapExplorer::ExtractScriptReferences(HeapEntry* entry, Script* script) {
+void V8HeapExplorer::ExtractScriptReferences(HeapEntry* entry, Script script) {
   SetInternalReference(entry, "source", script->source(),
                        Script::kSourceOffset);
   SetInternalReference(entry, "name", script->name(), Script::kNameOffset);
@@ -1082,8 +1103,8 @@ void V8HeapExplorer::ExtractScriptReferences(HeapEntry* entry, Script* script) {
                        Script::kLineEndsOffset);
 }
 
-void V8HeapExplorer::ExtractAccessorInfoReferences(
-    HeapEntry* entry, AccessorInfo* accessor_info) {
+void V8HeapExplorer::ExtractAccessorInfoReferences(HeapEntry* entry,
+                                                   AccessorInfo accessor_info) {
   SetInternalReference(entry, "name", accessor_info->name(),
                        AccessorInfo::kNameOffset);
   SetInternalReference(entry, "expected_receiver_type",
@@ -1098,27 +1119,18 @@ void V8HeapExplorer::ExtractAccessorInfoReferences(
 }
 
 void V8HeapExplorer::ExtractAccessorPairReferences(HeapEntry* entry,
-                                                   AccessorPair* accessors) {
+                                                   AccessorPair accessors) {
   SetInternalReference(entry, "getter", accessors->getter(),
                        AccessorPair::kGetterOffset);
   SetInternalReference(entry, "setter", accessors->setter(),
                        AccessorPair::kSetterOffset);
 }
 
-void V8HeapExplorer::TagBuiltinCodeObject(Code* code, const char* name) {
+void V8HeapExplorer::TagBuiltinCodeObject(Code code, const char* name) {
   TagObject(code, names_->GetFormatted("(%s builtin)", name));
 }
 
-void V8HeapExplorer::TagCodeObject(Code* code) {
-  if (code->kind() == Code::STUB) {
-    TagObject(code, names_->GetFormatted(
-                        "(%s code)",
-                        CodeStub::MajorName(CodeStub::GetMajorKey(code))));
-  }
-}
-
-void V8HeapExplorer::ExtractCodeReferences(HeapEntry* entry, Code* code) {
-  TagCodeObject(code);
+void V8HeapExplorer::ExtractCodeReferences(HeapEntry* entry, Code code) {
   TagObject(code->relocation_info(), "(code relocation info)");
   SetInternalReference(entry, "relocation_info", code->relocation_info(),
                        Code::kRelocationInfoOffset);
@@ -1132,19 +1144,19 @@ void V8HeapExplorer::ExtractCodeReferences(HeapEntry* entry, Code* code) {
                        Code::kSourcePositionTableOffset);
 }
 
-void V8HeapExplorer::ExtractCellReferences(HeapEntry* entry, Cell* cell) {
+void V8HeapExplorer::ExtractCellReferences(HeapEntry* entry, Cell cell) {
   SetInternalReference(entry, "value", cell->value(), Cell::kValueOffset);
 }
 
-void V8HeapExplorer::ExtractFeedbackCellReferences(
-    HeapEntry* entry, FeedbackCell* feedback_cell) {
+void V8HeapExplorer::ExtractFeedbackCellReferences(HeapEntry* entry,
+                                                   FeedbackCell feedback_cell) {
   TagObject(feedback_cell, "(feedback cell)");
   SetInternalReference(entry, "value", feedback_cell->value(),
                        FeedbackCell::kValueOffset);
 }
 
 void V8HeapExplorer::ExtractPropertyCellReferences(HeapEntry* entry,
-                                                   PropertyCell* cell) {
+                                                   PropertyCell cell) {
   SetInternalReference(entry, "value", cell->value(),
                        PropertyCell::kValueOffset);
   TagObject(cell->dependent_code(), "(dependent code)");
@@ -1153,7 +1165,7 @@ void V8HeapExplorer::ExtractPropertyCellReferences(HeapEntry* entry,
 }
 
 void V8HeapExplorer::ExtractAllocationSiteReferences(HeapEntry* entry,
-                                                     AllocationSite* site) {
+                                                     AllocationSite site) {
   SetInternalReference(entry, "transition_info",
                        site->transition_info_or_boilerplate(),
                        AllocationSite::kTransitionInfoOrBoilerplateOffset);
@@ -1165,7 +1177,7 @@ void V8HeapExplorer::ExtractAllocationSiteReferences(HeapEntry* entry,
 }
 
 void V8HeapExplorer::ExtractArrayBoilerplateDescriptionReferences(
-    HeapEntry* entry, ArrayBoilerplateDescription* value) {
+    HeapEntry* entry, ArrayBoilerplateDescription value) {
   SetInternalReference(entry, "constant_elements", value->constant_elements(),
                        ArrayBoilerplateDescription::kConstantElementsOffset);
 }
@@ -1187,10 +1199,9 @@ class JSArrayBufferDataEntryAllocator : public HeapEntriesAllocator {
 };
 
 void V8HeapExplorer::ExtractJSArrayBufferReferences(HeapEntry* entry,
-                                                    JSArrayBuffer* buffer) {
+                                                    JSArrayBuffer buffer) {
   // Setup a reference to a native memory backing_store object.
-  if (!buffer->backing_store())
-    return;
+  if (!buffer->backing_store()) return;
   size_t data_size = buffer->byte_length();
   JSArrayBufferDataEntryAllocator allocator(data_size, this);
   HeapEntry* data_entry =
@@ -1200,14 +1211,14 @@ void V8HeapExplorer::ExtractJSArrayBufferReferences(HeapEntry* entry,
 }
 
 void V8HeapExplorer::ExtractJSPromiseReferences(HeapEntry* entry,
-                                                JSPromise* promise) {
+                                                JSPromise promise) {
   SetInternalReference(entry, "reactions_or_result",
                        promise->reactions_or_result(),
                        JSPromise::kReactionsOrResultOffset);
 }
 
 void V8HeapExplorer::ExtractJSGeneratorObjectReferences(
-    HeapEntry* entry, JSGeneratorObject* generator) {
+    HeapEntry* entry, JSGeneratorObject generator) {
   SetInternalReference(entry, "function", generator->function(),
                        JSGeneratorObject::kFunctionOffset);
   SetInternalReference(entry, "context", generator->context(),
@@ -1220,7 +1231,7 @@ void V8HeapExplorer::ExtractJSGeneratorObjectReferences(
 }
 
 void V8HeapExplorer::ExtractFixedArrayReferences(HeapEntry* entry,
-                                                 FixedArray* array) {
+                                                 FixedArray array) {
   for (int i = 0, l = array->length(); i < l; ++i) {
     DCHECK(!HasWeakHeapObjectTag(array->get(i)));
     SetInternalReference(entry, i, array->get(i), array->OffsetOfElementAt(i));
@@ -1228,35 +1239,55 @@ void V8HeapExplorer::ExtractFixedArrayReferences(HeapEntry* entry,
 }
 
 void V8HeapExplorer::ExtractFeedbackVectorReferences(
-    HeapEntry* entry, FeedbackVector* feedback_vector) {
-  MaybeObject* code = feedback_vector->optimized_code_weak_or_smi();
-  HeapObject* code_heap_object;
+    HeapEntry* entry, FeedbackVector feedback_vector) {
+  MaybeObject code = feedback_vector->optimized_code_weak_or_smi();
+  HeapObject code_heap_object;
   if (code->GetHeapObjectIfWeak(&code_heap_object)) {
     SetWeakReference(entry, "optimized code", code_heap_object,
                      FeedbackVector::kOptimizedCodeOffset);
   }
 }
 
+void V8HeapExplorer::ExtractDescriptorArrayReferences(HeapEntry* entry,
+                                                      DescriptorArray array) {
+  SetInternalReference(entry, "enum_cache", array->enum_cache(),
+                       DescriptorArray::kEnumCacheOffset);
+  MaybeObjectSlot start = MaybeObjectSlot(array->GetDescriptorSlot(0));
+  MaybeObjectSlot end = MaybeObjectSlot(
+      array->GetDescriptorSlot(array->number_of_all_descriptors()));
+  for (int i = 0; start + i < end; ++i) {
+    MaybeObjectSlot slot = start + i;
+    int offset = static_cast<int>(slot.address() - array->address());
+    MaybeObject object = *slot;
+    HeapObject heap_object;
+    if (object->GetHeapObjectIfWeak(&heap_object)) {
+      SetWeakReference(entry, i, heap_object, offset);
+    } else if (object->GetHeapObjectIfStrong(&heap_object)) {
+      SetInternalReference(entry, i, heap_object, offset);
+    }
+  }
+}
+
 template <typename T>
 void V8HeapExplorer::ExtractWeakArrayReferences(int header_size,
-                                                HeapEntry* entry, T* array) {
+                                                HeapEntry* entry, T array) {
   for (int i = 0; i < array->length(); ++i) {
-    MaybeObject* object = array->Get(i);
-    HeapObject* heap_object;
+    MaybeObject object = array->Get(i);
+    HeapObject heap_object;
     if (object->GetHeapObjectIfWeak(&heap_object)) {
-      SetWeakReference(entry, i, heap_object, header_size + i * kPointerSize);
+      SetWeakReference(entry, i, heap_object, header_size + i * kTaggedSize);
     } else if (object->GetHeapObjectIfStrong(&heap_object)) {
       SetInternalReference(entry, i, heap_object,
-                           header_size + i * kPointerSize);
+                           header_size + i * kTaggedSize);
     }
   }
 }
 
-void V8HeapExplorer::ExtractPropertyReferences(JSObject* js_obj,
+void V8HeapExplorer::ExtractPropertyReferences(JSObject js_obj,
                                                HeapEntry* entry) {
   Isolate* isolate = js_obj->GetIsolate();
   if (js_obj->HasFastProperties()) {
-    DescriptorArray* descs = js_obj->map()->instance_descriptors();
+    DescriptorArray descs = js_obj->map()->instance_descriptors();
     int real_size = js_obj->map()->NumberOfOwnDescriptors();
     for (int i = 0; i < real_size; i++) {
       PropertyDetails details = descs->GetDetails(i);
@@ -1265,9 +1296,9 @@ void V8HeapExplorer::ExtractPropertyReferences(JSObject* js_obj,
           Representation r = details.representation();
           if (r.IsSmi() || r.IsDouble()) break;
 
-          Name* k = descs->GetKey(i);
+          Name k = descs->GetKey(i);
           FieldIndex field_index = FieldIndex::ForDescriptor(js_obj->map(), i);
-          Object* value = js_obj->RawFastPropertyAt(field_index);
+          Object value = js_obj->RawFastPropertyAt(field_index);
           int field_offset =
               field_index.is_inobject() ? field_index.offset() : -1;
 
@@ -1284,26 +1315,26 @@ void V8HeapExplorer::ExtractPropertyReferences(JSObject* js_obj,
     }
   } else if (js_obj->IsJSGlobalObject()) {
     // We assume that global objects can only have slow properties.
-    GlobalDictionary* dictionary =
+    GlobalDictionary dictionary =
         JSGlobalObject::cast(js_obj)->global_dictionary();
     int length = dictionary->Capacity();
     ReadOnlyRoots roots(isolate);
     for (int i = 0; i < length; ++i) {
       if (!dictionary->IsKey(roots, dictionary->KeyAt(i))) continue;
-      PropertyCell* cell = dictionary->CellAt(i);
-      Name* name = cell->name();
-      Object* value = cell->value();
+      PropertyCell cell = dictionary->CellAt(i);
+      Name name = cell->name();
+      Object value = cell->value();
       PropertyDetails details = cell->property_details();
       SetDataOrAccessorPropertyReference(details.kind(), entry, name, value);
     }
   } else {
-    NameDictionary* dictionary = js_obj->property_dictionary();
+    NameDictionary dictionary = js_obj->property_dictionary();
     int length = dictionary->Capacity();
     ReadOnlyRoots roots(isolate);
     for (int i = 0; i < length; ++i) {
-      Object* k = dictionary->KeyAt(i);
+      Object k = dictionary->KeyAt(i);
       if (!dictionary->IsKey(roots, k)) continue;
-      Object* value = dictionary->ValueAt(i);
+      Object value = dictionary->ValueAt(i);
       PropertyDetails details = dictionary->DetailsAt(i);
       SetDataOrAccessorPropertyReference(details.kind(), entry, Name::cast(k),
                                          value);
@@ -1311,27 +1342,27 @@ void V8HeapExplorer::ExtractPropertyReferences(JSObject* js_obj,
   }
 }
 
-void V8HeapExplorer::ExtractAccessorPairProperty(HeapEntry* entry, Name* key,
-                                                 Object* callback_obj,
+void V8HeapExplorer::ExtractAccessorPairProperty(HeapEntry* entry, Name key,
+                                                 Object callback_obj,
                                                  int field_offset) {
   if (!callback_obj->IsAccessorPair()) return;
-  AccessorPair* accessors = AccessorPair::cast(callback_obj);
+  AccessorPair accessors = AccessorPair::cast(callback_obj);
   SetPropertyReference(entry, key, accessors, nullptr, field_offset);
-  Object* getter = accessors->getter();
+  Object getter = accessors->getter();
   if (!getter->IsOddball()) {
     SetPropertyReference(entry, key, getter, "get %s");
   }
-  Object* setter = accessors->setter();
+  Object setter = accessors->setter();
   if (!setter->IsOddball()) {
     SetPropertyReference(entry, key, setter, "set %s");
   }
 }
 
-void V8HeapExplorer::ExtractElementReferences(JSObject* js_obj,
+void V8HeapExplorer::ExtractElementReferences(JSObject js_obj,
                                               HeapEntry* entry) {
   ReadOnlyRoots roots = js_obj->GetReadOnlyRoots();
   if (js_obj->HasObjectElements()) {
-    FixedArray* elements = FixedArray::cast(js_obj->elements());
+    FixedArray elements = FixedArray::cast(js_obj->elements());
     int length = js_obj->IsJSArray()
                      ? Smi::ToInt(JSArray::cast(js_obj)->length())
                      : elements->length();
@@ -1341,10 +1372,10 @@ void V8HeapExplorer::ExtractElementReferences(JSObject* js_obj,
       }
     }
   } else if (js_obj->HasDictionaryElements()) {
-    NumberDictionary* dictionary = js_obj->element_dictionary();
+    NumberDictionary dictionary = js_obj->element_dictionary();
     int length = dictionary->Capacity();
     for (int i = 0; i < length; ++i) {
-      Object* k = dictionary->KeyAt(i);
+      Object k = dictionary->KeyAt(i);
       if (!dictionary->IsKey(roots, k)) continue;
       DCHECK(k->IsNumber());
       uint32_t index = static_cast<uint32_t>(k->Number());
@@ -1353,28 +1384,28 @@ void V8HeapExplorer::ExtractElementReferences(JSObject* js_obj,
   }
 }
 
-void V8HeapExplorer::ExtractInternalReferences(JSObject* js_obj,
+void V8HeapExplorer::ExtractInternalReferences(JSObject js_obj,
                                                HeapEntry* entry) {
   int length = js_obj->GetEmbedderFieldCount();
   for (int i = 0; i < length; ++i) {
-    Object* o = js_obj->GetEmbedderField(i);
+    Object o = js_obj->GetEmbedderField(i);
     SetInternalReference(entry, i, o, js_obj->GetEmbedderFieldOffset(i));
   }
 }
 
-JSFunction* V8HeapExplorer::GetConstructor(JSReceiver* receiver) {
+JSFunction V8HeapExplorer::GetConstructor(JSReceiver receiver) {
   Isolate* isolate = receiver->GetIsolate();
   DisallowHeapAllocation no_gc;
   HandleScope scope(isolate);
   MaybeHandle<JSFunction> maybe_constructor =
       JSReceiver::GetConstructor(handle(receiver, isolate));
 
-  if (maybe_constructor.is_null()) return nullptr;
+  if (maybe_constructor.is_null()) return JSFunction();
 
   return *maybe_constructor.ToHandleChecked();
 }
 
-String* V8HeapExplorer::GetConstructorName(JSObject* object) {
+String V8HeapExplorer::GetConstructorName(JSObject object) {
   Isolate* isolate = object->GetIsolate();
   if (object->IsJSFunction()) return ReadOnlyRoots(isolate).closure_string();
   DisallowHeapAllocation no_gc;
@@ -1382,8 +1413,10 @@ String* V8HeapExplorer::GetConstructorName(JSObject* object) {
   return *JSReceiver::GetConstructorName(handle(object, isolate));
 }
 
-HeapEntry* V8HeapExplorer::GetEntry(Object* obj) {
-  return obj->IsHeapObject() ? generator_->FindOrAddEntry(obj, this) : nullptr;
+HeapEntry* V8HeapExplorer::GetEntry(Object obj) {
+  return obj->IsHeapObject() ? generator_->FindOrAddEntry(
+                                   reinterpret_cast<void*>(obj.ptr()), this)
+                             : nullptr;
 }
 
 class RootsReferencesExtractor : public RootVisitor {
@@ -1394,7 +1427,7 @@ class RootsReferencesExtractor : public RootVisitor {
   void SetVisitingWeakRoots() { visiting_weak_roots_ = true; }
 
   void VisitRootPointer(Root root, const char* description,
-                        Object** object) override {
+                        FullObjectSlot object) override {
     if (root == Root::kBuiltins) {
       explorer_->TagBuiltinCodeObject(Code::cast(*object), description);
     }
@@ -1402,10 +1435,11 @@ class RootsReferencesExtractor : public RootVisitor {
                                      *object);
   }
 
-  void VisitRootPointers(Root root, const char* description, Object** start,
-                         Object** end) override {
-    for (Object** p = start; p < end; p++)
+  void VisitRootPointers(Root root, const char* description,
+                         FullObjectSlot start, FullObjectSlot end) override {
+    for (FullObjectSlot p = start; p < end; ++p) {
       VisitRootPointer(root, description, p);
+    }
   }
 
  private:
@@ -1427,7 +1461,8 @@ bool V8HeapExplorer::IterateAndExtractReferences(
   // first. Otherwise a particular JSFunction object could set
   // its custom name to a generic builtin.
   RootsReferencesExtractor extractor(this);
-  heap_->IterateRoots(&extractor, VISIT_ONLY_STRONG_FOR_SERIALIZATION);
+  ReadOnlyRoots(heap_).Iterate(&extractor);
+  heap_->IterateRoots(&extractor, VISIT_ONLY_STRONG);
   extractor.SetVisitingWeakRoots();
   heap_->IterateWeakGlobalHandles(&extractor);
 
@@ -1435,11 +1470,11 @@ bool V8HeapExplorer::IterateAndExtractReferences(
 
   HeapIterator iterator(heap_, HeapIterator::kFilterUnreachable);
   // Heap iteration with filtering must be finished in any case.
-  for (HeapObject *obj = iterator.next(); obj != nullptr;
+  for (HeapObject obj = iterator.next(); !obj.is_null();
        obj = iterator.next(), progress_->ProgressStep()) {
     if (interrupted) continue;
 
-    size_t max_pointer = obj->Size() / kPointerSize;
+    size_t max_pointer = obj->Size() / kTaggedSize;
     if (max_pointer > visited_fields_.size()) {
       // Clear the current bits.
       std::vector<bool>().swap(visited_fields_);
@@ -1470,8 +1505,7 @@ bool V8HeapExplorer::IterateAndExtractReferences(
   return interrupted ? false : progress_->ProgressReport(true);
 }
 
-
-bool V8HeapExplorer::IsEssentialObject(Object* object) {
+bool V8HeapExplorer::IsEssentialObject(Object object) {
   ReadOnlyRoots roots(heap_);
   return object->IsHeapObject() && !object->IsOddball() &&
          object != roots.empty_byte_array() &&
@@ -1486,7 +1520,7 @@ bool V8HeapExplorer::IsEssentialObject(Object* object) {
          object != roots.two_pointer_filler_map();
 }
 
-bool V8HeapExplorer::IsEssentialHiddenReference(Object* parent,
+bool V8HeapExplorer::IsEssentialHiddenReference(Object parent,
                                                 int field_offset) {
   if (parent->IsAllocationSite() &&
       field_offset == AllocationSite::kWeakNextOffset)
@@ -1501,8 +1535,8 @@ bool V8HeapExplorer::IsEssentialHiddenReference(Object* parent,
 }
 
 void V8HeapExplorer::SetContextReference(HeapEntry* parent_entry,
-                                         String* reference_name,
-                                         Object* child_obj, int field_offset) {
+                                         String reference_name,
+                                         Object child_obj, int field_offset) {
   HeapEntry* child_entry = GetEntry(child_obj);
   if (child_entry == nullptr) return;
   parent_entry->SetNamedReference(HeapGraphEdge::kContextVariable,
@@ -1512,14 +1546,14 @@ void V8HeapExplorer::SetContextReference(HeapEntry* parent_entry,
 
 void V8HeapExplorer::MarkVisitedField(int offset) {
   if (offset < 0) return;
-  int index = offset / kPointerSize;
+  int index = offset / kTaggedSize;
   DCHECK(!visited_fields_[index]);
   visited_fields_[index] = true;
 }
 
 void V8HeapExplorer::SetNativeBindReference(HeapEntry* parent_entry,
                                             const char* reference_name,
-                                            Object* child_obj) {
+                                            Object child_obj) {
   HeapEntry* child_entry = GetEntry(child_obj);
   if (child_entry == nullptr) return;
   parent_entry->SetNamedReference(HeapGraphEdge::kShortcut, reference_name,
@@ -1527,7 +1561,7 @@ void V8HeapExplorer::SetNativeBindReference(HeapEntry* parent_entry,
 }
 
 void V8HeapExplorer::SetElementReference(HeapEntry* parent_entry, int index,
-                                         Object* child_obj) {
+                                         Object child_obj) {
   HeapEntry* child_entry = GetEntry(child_obj);
   if (child_entry == nullptr) return;
   parent_entry->SetIndexedReference(HeapGraphEdge::kElement, index,
@@ -1536,7 +1570,7 @@ void V8HeapExplorer::SetElementReference(HeapEntry* parent_entry, int index,
 
 void V8HeapExplorer::SetInternalReference(HeapEntry* parent_entry,
                                           const char* reference_name,
-                                          Object* child_obj, int field_offset) {
+                                          Object child_obj, int field_offset) {
   HeapEntry* child_entry = GetEntry(child_obj);
   if (child_entry == nullptr) return;
   if (IsEssentialObject(child_obj)) {
@@ -1547,7 +1581,7 @@ void V8HeapExplorer::SetInternalReference(HeapEntry* parent_entry,
 }
 
 void V8HeapExplorer::SetInternalReference(HeapEntry* parent_entry, int index,
-                                          Object* child_obj, int field_offset) {
+                                          Object child_obj, int field_offset) {
   HeapEntry* child_entry = GetEntry(child_obj);
   if (child_entry == nullptr) return;
   if (IsEssentialObject(child_obj)) {
@@ -1557,9 +1591,9 @@ void V8HeapExplorer::SetInternalReference(HeapEntry* parent_entry, int index,
   MarkVisitedField(field_offset);
 }
 
-void V8HeapExplorer::SetHiddenReference(HeapObject* parent_obj,
+void V8HeapExplorer::SetHiddenReference(HeapObject parent_obj,
                                         HeapEntry* parent_entry, int index,
-                                        Object* child_obj, int field_offset) {
+                                        Object child_obj, int field_offset) {
   DCHECK_EQ(parent_entry, GetEntry(parent_obj));
   HeapEntry* child_entry = GetEntry(child_obj);
   if (child_entry != nullptr && IsEssentialObject(child_obj) &&
@@ -1571,7 +1605,7 @@ void V8HeapExplorer::SetHiddenReference(HeapObject* parent_obj,
 
 void V8HeapExplorer::SetWeakReference(HeapEntry* parent_entry,
                                       const char* reference_name,
-                                      Object* child_obj, int field_offset) {
+                                      Object child_obj, int field_offset) {
   HeapEntry* child_entry = GetEntry(child_obj);
   if (child_entry == nullptr) return;
   if (IsEssentialObject(child_obj)) {
@@ -1582,7 +1616,7 @@ void V8HeapExplorer::SetWeakReference(HeapEntry* parent_entry,
 }
 
 void V8HeapExplorer::SetWeakReference(HeapEntry* parent_entry, int index,
-                                      Object* child_obj, int field_offset) {
+                                      Object child_obj, int field_offset) {
   HeapEntry* child_entry = GetEntry(child_obj);
   if (child_entry == nullptr) return;
   if (IsEssentialObject(child_obj)) {
@@ -1593,8 +1627,8 @@ void V8HeapExplorer::SetWeakReference(HeapEntry* parent_entry, int index,
 }
 
 void V8HeapExplorer::SetDataOrAccessorPropertyReference(
-    PropertyKind kind, HeapEntry* parent_entry, Name* reference_name,
-    Object* child_obj, const char* name_format_string, int field_offset) {
+    PropertyKind kind, HeapEntry* parent_entry, Name reference_name,
+    Object child_obj, const char* name_format_string, int field_offset) {
   if (kind == kAccessor) {
     ExtractAccessorPairProperty(parent_entry, reference_name, child_obj,
                                 field_offset);
@@ -1605,8 +1639,7 @@ void V8HeapExplorer::SetDataOrAccessorPropertyReference(
 }
 
 void V8HeapExplorer::SetPropertyReference(HeapEntry* parent_entry,
-                                          Name* reference_name,
-                                          Object* child_obj,
+                                          Name reference_name, Object child_obj,
                                           const char* name_format_string,
                                           int field_offset) {
   HeapEntry* child_entry = GetEntry(child_obj);
@@ -1633,7 +1666,7 @@ void V8HeapExplorer::SetRootGcRootsReference() {
                                                   snapshot_->gc_roots());
 }
 
-void V8HeapExplorer::SetUserGlobalReference(Object* child_obj) {
+void V8HeapExplorer::SetUserGlobalReference(Object child_obj) {
   HeapEntry* child_entry = GetEntry(child_obj);
   DCHECK_NOT_NULL(child_entry);
   snapshot_->root()->SetNamedAutoIndexReference(HeapGraphEdge::kShortcut,
@@ -1646,7 +1679,7 @@ void V8HeapExplorer::SetGcRootsReference(Root root) {
 }
 
 void V8HeapExplorer::SetGcSubrootReference(Root root, const char* description,
-                                           bool is_weak, Object* child_obj) {
+                                           bool is_weak, Object child_obj) {
   HeapEntry* child_entry = GetEntry(child_obj);
   if (child_entry == nullptr) return;
   const char* name = GetStrongGcSubrootName(child_obj);
@@ -1665,7 +1698,7 @@ void V8HeapExplorer::SetGcSubrootReference(Root root, const char* description,
   // also used as starting points in distance calculations.
   if (is_weak || !child_obj->IsNativeContext()) return;
 
-  JSGlobalObject* global = Context::cast(child_obj)->global_object();
+  JSGlobalObject global = Context::cast(child_obj)->global_object();
   if (!global->IsJSGlobalObject()) return;
 
   if (!user_roots_.insert(global).second) return;
@@ -1673,24 +1706,13 @@ void V8HeapExplorer::SetGcSubrootReference(Root root, const char* description,
   SetUserGlobalReference(global);
 }
 
-// This static array is used to prevent excessive code-size in
-// GetStrongGcSubrootName below, which would happen if we called emplace() for
-// every root in a macro.
-static const char* root_names[] = {
-#define ROOT_NAME(type, name, CamelName) #name,
-    READ_ONLY_ROOT_LIST(ROOT_NAME) MUTABLE_ROOT_LIST(ROOT_NAME)
-#undef ROOT_NAME
-};
-STATIC_ASSERT(static_cast<uint16_t>(RootIndex::kRootListLength) ==
-              arraysize(root_names));
-
-const char* V8HeapExplorer::GetStrongGcSubrootName(Object* object) {
+const char* V8HeapExplorer::GetStrongGcSubrootName(Object object) {
   if (strong_gc_subroot_names_.empty()) {
-    for (uint16_t i = 0; i < static_cast<uint16_t>(RootIndex::kRootListLength);
-         i++) {
-      const char* name = root_names[i];
-      RootIndex index = static_cast<RootIndex>(i);
-      strong_gc_subroot_names_.emplace(heap_->root(index), name);
+    Isolate* isolate = heap_->isolate();
+    for (RootIndex root_index = RootIndex::kFirstStrongOrReadOnlyRoot;
+         root_index <= RootIndex::kLastStrongOrReadOnlyRoot; ++root_index) {
+      const char* name = RootsTable::name(root_index);
+      strong_gc_subroot_names_.emplace(isolate->root(root_index), name);
     }
     CHECK(!strong_gc_subroot_names_.empty());
   }
@@ -1698,7 +1720,7 @@ const char* V8HeapExplorer::GetStrongGcSubrootName(Object* object) {
   return it != strong_gc_subroot_names_.end() ? it->second : nullptr;
 }
 
-void V8HeapExplorer::TagObject(Object* obj, const char* tag) {
+void V8HeapExplorer::TagObject(Object obj, const char* tag) {
   if (IsEssentialObject(obj)) {
     HeapEntry* entry = GetEntry(obj);
     if (entry->name()[0] == '\0') {
@@ -1709,13 +1731,13 @@ void V8HeapExplorer::TagObject(Object* obj, const char* tag) {
 
 class GlobalObjectsEnumerator : public RootVisitor {
  public:
-  void VisitRootPointers(Root root, const char* description, Object** start,
-                         Object** end) override {
-    for (Object** p = start; p < end; p++) {
+  void VisitRootPointers(Root root, const char* description,
+                         FullObjectSlot start, FullObjectSlot end) override {
+    for (FullObjectSlot p = start; p < end; ++p) {
       if (!(*p)->IsNativeContext()) continue;
-      JSObject* proxy = Context::cast(*p)->global_proxy();
+      JSObject proxy = Context::cast(*p)->global_proxy();
       if (!proxy->IsJSGlobalProxy()) continue;
-      Object* global = proxy->map()->prototype();
+      Object global = proxy->map()->prototype();
       if (!global->IsJSGlobalObject()) continue;
       objects_.push_back(Handle<JSGlobalObject>(JSGlobalObject::cast(global),
                                                 proxy->GetIsolate()));
@@ -1759,8 +1781,8 @@ class EmbedderGraphImpl : public EmbedderGraph {
 
   class V8NodeImpl : public Node {
    public:
-    explicit V8NodeImpl(Object* object) : object_(object) {}
-    Object* GetObject() { return object_; }
+    explicit V8NodeImpl(Object object) : object_(object) {}
+    Object GetObject() { return object_; }
 
     // Node overrides.
     bool IsEmbedderNode() override { return false; }
@@ -1776,7 +1798,7 @@ class EmbedderGraphImpl : public EmbedderGraph {
     }
 
    private:
-    Object* object_;
+    Object object_;
   };
 
   Node* V8Node(const v8::Local<v8::Value>& value) final {
@@ -1811,7 +1833,7 @@ class GlobalHandlesExtractor : public PersistentHandleVisitor {
   void VisitPersistentHandle(Persistent<Value>* value,
                              uint16_t class_id) override {
     Handle<Object> object = Utils::OpenPersistent(value);
-    explorer_->VisitSubtreeWrapper(object.location(), class_id);
+    explorer_->VisitSubtreeWrapper(object, class_id);
   }
 
  private:
@@ -1948,7 +1970,7 @@ NativeObjectsExplorer::~NativeObjectsExplorer() {
   for (auto map_entry : objects_by_info_) {
     v8::RetainedObjectInfo* info = map_entry.first;
     info->Dispose();
-    std::vector<HeapObject*>* objects = map_entry.second;
+    std::vector<HeapObject>* objects = map_entry.second;
     delete objects;
   }
   for (auto map_entry : native_groups_) {
@@ -1970,14 +1992,14 @@ void NativeObjectsExplorer::FillRetainedObjects() {
   v8::HeapProfiler::RetainerInfos infos =
       snapshot_->profiler()->GetRetainerInfos(isolate_);
   for (auto& pair : infos.groups) {
-    std::vector<HeapObject*>* info = GetVectorMaybeDisposeInfo(pair.first);
+    std::vector<HeapObject>* info = GetVectorMaybeDisposeInfo(pair.first);
     for (auto& persistent : pair.second) {
       if (persistent->IsEmpty()) continue;
 
       Handle<Object> object = v8::Utils::OpenHandle(
           *persistent->Get(reinterpret_cast<v8::Isolate*>(isolate_)));
       DCHECK(!object.is_null());
-      HeapObject* heap_object = HeapObject::cast(*object);
+      HeapObject heap_object = HeapObject::cast(*object);
       info->push_back(heap_object);
       in_groups_.insert(heap_object);
     }
@@ -1999,27 +2021,27 @@ void NativeObjectsExplorer::FillEdges() {
 
     Handle<Object> parent_object = v8::Utils::OpenHandle(
         *pair.first->Get(reinterpret_cast<v8::Isolate*>(isolate_)));
-    HeapObject* parent = HeapObject::cast(*parent_object);
-    HeapEntry* parent_entry =
-        generator_->FindOrAddEntry(parent, native_entries_allocator_.get());
+    HeapObject parent = HeapObject::cast(*parent_object);
+    HeapEntry* parent_entry = generator_->FindOrAddEntry(
+        reinterpret_cast<void*>(parent.ptr()), native_entries_allocator_.get());
     DCHECK_NOT_NULL(parent_entry);
     Handle<Object> child_object = v8::Utils::OpenHandle(
         *pair.second->Get(reinterpret_cast<v8::Isolate*>(isolate_)));
-    HeapObject* child = HeapObject::cast(*child_object);
-    HeapEntry* child_entry =
-        generator_->FindOrAddEntry(child, native_entries_allocator_.get());
+    HeapObject child = HeapObject::cast(*child_object);
+    HeapEntry* child_entry = generator_->FindOrAddEntry(
+        reinterpret_cast<void*>(child.ptr()), native_entries_allocator_.get());
     parent_entry->SetNamedReference(HeapGraphEdge::kInternal, "native",
                                     child_entry);
   }
   edges_.clear();
 }
 
-std::vector<HeapObject*>* NativeObjectsExplorer::GetVectorMaybeDisposeInfo(
+std::vector<HeapObject>* NativeObjectsExplorer::GetVectorMaybeDisposeInfo(
     v8::RetainedObjectInfo* info) {
   if (objects_by_info_.count(info)) {
     info->Dispose();
   } else {
-    objects_by_info_[info] = new std::vector<HeapObject*>();
+    objects_by_info_[info] = new std::vector<HeapObject>();
   }
   return objects_by_info_[info];
 }
@@ -2036,9 +2058,10 @@ HeapEntry* NativeObjectsExplorer::EntryForEmbedderGraphNode(
   } else {
     EmbedderGraphImpl::V8NodeImpl* v8_node =
         static_cast<EmbedderGraphImpl::V8NodeImpl*>(node);
-    Object* object = v8_node->GetObject();
+    Object object = v8_node->GetObject();
     if (object->IsSmi()) return nullptr;
-    return generator_->FindEntry(HeapObject::cast(object));
+    return generator_->FindEntry(
+        reinterpret_cast<void*>(Object::cast(object).ptr()));
   }
 }
 
@@ -2088,8 +2111,8 @@ bool NativeObjectsExplorer::IterateAndExtractReferences(
       for (auto map_entry : objects_by_info_) {
         v8::RetainedObjectInfo* info = map_entry.first;
         SetNativeRootReference(info);
-        std::vector<HeapObject*>* objects = map_entry.second;
-        for (HeapObject* object : *objects) {
+        std::vector<HeapObject>* objects = map_entry.second;
+        for (HeapObject object : *objects) {
           SetWrapperNativeReferences(object, info);
         }
       }
@@ -2123,8 +2146,9 @@ void NativeObjectsExplorer::SetNativeRootReference(
 }
 
 void NativeObjectsExplorer::SetWrapperNativeReferences(
-    HeapObject* wrapper, v8::RetainedObjectInfo* info) {
-  HeapEntry* wrapper_entry = generator_->FindEntry(wrapper);
+    HeapObject wrapper, v8::RetainedObjectInfo* info) {
+  HeapEntry* wrapper_entry =
+      generator_->FindEntry(reinterpret_cast<void*>(wrapper.ptr()));
   DCHECK_NOT_NULL(wrapper_entry);
   HeapEntry* info_entry =
       generator_->FindOrAddEntry(info, native_entries_allocator_.get());
@@ -2146,7 +2170,8 @@ void NativeObjectsExplorer::SetRootNativeRootsReference() {
   }
 }
 
-void NativeObjectsExplorer::VisitSubtreeWrapper(Object** p, uint16_t class_id) {
+void NativeObjectsExplorer::VisitSubtreeWrapper(Handle<Object> p,
+                                                uint16_t class_id) {
   if (in_groups_.count(*p)) return;
   v8::RetainedObjectInfo* info =
       isolate_->heap_profiler()->ExecuteWrapperClassCallback(class_id, p);
@@ -2171,13 +2196,13 @@ class NullContextScope {
  public:
   explicit NullContextScope(Isolate* isolate)
       : isolate_(isolate), prev_(isolate->context()) {
-    isolate_->set_context(nullptr);
+    isolate_->set_context(Context());
   }
   ~NullContextScope() { isolate_->set_context(prev_); }
 
  private:
   Isolate* isolate_;
-  Context* prev_;
+  Context prev_;
 };
 }  //  namespace
 
diff --git a/deps/v8/src/profiler/heap-snapshot-generator.h b/deps/v8/src/profiler/heap-snapshot-generator.h
index 1f8f364912..14cce75f90 100644
--- a/deps/v8/src/profiler/heap-snapshot-generator.h
+++ b/deps/v8/src/profiler/heap-snapshot-generator.h
@@ -15,6 +15,8 @@
 #include "src/objects.h"
 #include "src/objects/fixed-array.h"
 #include "src/objects/hash-table.h"
+#include "src/objects/heap-object.h"
+#include "src/objects/js-objects.h"
 #include "src/objects/literal-objects.h"
 #include "src/profiler/strings-storage.h"
 #include "src/string-hasher.h"
@@ -322,106 +324,105 @@ class V8HeapExplorer : public HeapEntriesAllocator {
   int EstimateObjectsCount();
   bool IterateAndExtractReferences(HeapSnapshotGenerator* generator);
   void TagGlobalObjects();
-  void TagCodeObject(Code* code);
-  void TagBuiltinCodeObject(Code* code, const char* name);
+  void TagBuiltinCodeObject(Code code, const char* name);
   HeapEntry* AddEntry(Address address,
                       HeapEntry::Type type,
                       const char* name,
                       size_t size);
 
-  static JSFunction* GetConstructor(JSReceiver* receiver);
-  static String* GetConstructorName(JSObject* object);
+  static JSFunction GetConstructor(JSReceiver receiver);
+  static String GetConstructorName(JSObject object);
 
  private:
   void MarkVisitedField(int offset);
 
-  HeapEntry* AddEntry(HeapObject* object);
-  HeapEntry* AddEntry(HeapObject* object,
-                      HeapEntry::Type type,
+  HeapEntry* AddEntry(HeapObject object);
+  HeapEntry* AddEntry(HeapObject object, HeapEntry::Type type,
                       const char* name);
 
-  const char* GetSystemEntryName(HeapObject* object);
-
-  void ExtractLocation(HeapEntry* entry, HeapObject* object);
-  void ExtractLocationForJSFunction(HeapEntry* entry, JSFunction* func);
-  void ExtractReferences(HeapEntry* entry, HeapObject* obj);
-  void ExtractJSGlobalProxyReferences(HeapEntry* entry, JSGlobalProxy* proxy);
-  void ExtractJSObjectReferences(HeapEntry* entry, JSObject* js_obj);
-  void ExtractStringReferences(HeapEntry* entry, String* obj);
-  void ExtractSymbolReferences(HeapEntry* entry, Symbol* symbol);
-  void ExtractJSCollectionReferences(HeapEntry* entry,
-                                     JSCollection* collection);
+  const char* GetSystemEntryName(HeapObject object);
+
+  void ExtractLocation(HeapEntry* entry, HeapObject object);
+  void ExtractLocationForJSFunction(HeapEntry* entry, JSFunction func);
+  void ExtractReferences(HeapEntry* entry, HeapObject obj);
+  void ExtractJSGlobalProxyReferences(HeapEntry* entry, JSGlobalProxy proxy);
+  void ExtractJSObjectReferences(HeapEntry* entry, JSObject js_obj);
+  void ExtractStringReferences(HeapEntry* entry, String obj);
+  void ExtractSymbolReferences(HeapEntry* entry, Symbol symbol);
+  void ExtractJSCollectionReferences(HeapEntry* entry, JSCollection collection);
   void ExtractJSWeakCollectionReferences(HeapEntry* entry,
-                                         JSWeakCollection* collection);
+                                         JSWeakCollection collection);
   void ExtractEphemeronHashTableReferences(HeapEntry* entry,
-                                           EphemeronHashTable* table);
-  void ExtractContextReferences(HeapEntry* entry, Context* context);
-  void ExtractMapReferences(HeapEntry* entry, Map* map);
+                                           EphemeronHashTable table);
+  void ExtractContextReferences(HeapEntry* entry, Context context);
+  void ExtractMapReferences(HeapEntry* entry, Map map);
   void ExtractSharedFunctionInfoReferences(HeapEntry* entry,
-                                           SharedFunctionInfo* shared);
-  void ExtractScriptReferences(HeapEntry* entry, Script* script);
+                                           SharedFunctionInfo shared);
+  void ExtractScriptReferences(HeapEntry* entry, Script script);
   void ExtractAccessorInfoReferences(HeapEntry* entry,
-                                     AccessorInfo* accessor_info);
-  void ExtractAccessorPairReferences(HeapEntry* entry, AccessorPair* accessors);
-  void ExtractCodeReferences(HeapEntry* entry, Code* code);
-  void ExtractCellReferences(HeapEntry* entry, Cell* cell);
+                                     AccessorInfo accessor_info);
+  void ExtractAccessorPairReferences(HeapEntry* entry, AccessorPair accessors);
+  void ExtractCodeReferences(HeapEntry* entry, Code code);
+  void ExtractCellReferences(HeapEntry* entry, Cell cell);
   void ExtractFeedbackCellReferences(HeapEntry* entry,
-                                     FeedbackCell* feedback_cell);
-  void ExtractPropertyCellReferences(HeapEntry* entry, PropertyCell* cell);
-  void ExtractAllocationSiteReferences(HeapEntry* entry, AllocationSite* site);
+                                     FeedbackCell feedback_cell);
+  void ExtractPropertyCellReferences(HeapEntry* entry, PropertyCell cell);
+  void ExtractAllocationSiteReferences(HeapEntry* entry, AllocationSite site);
   void ExtractArrayBoilerplateDescriptionReferences(
-      HeapEntry* entry, ArrayBoilerplateDescription* value);
-  void ExtractJSArrayBufferReferences(HeapEntry* entry, JSArrayBuffer* buffer);
-  void ExtractJSPromiseReferences(HeapEntry* entry, JSPromise* promise);
+      HeapEntry* entry, ArrayBoilerplateDescription value);
+  void ExtractJSArrayBufferReferences(HeapEntry* entry, JSArrayBuffer buffer);
+  void ExtractJSPromiseReferences(HeapEntry* entry, JSPromise promise);
   void ExtractJSGeneratorObjectReferences(HeapEntry* entry,
-                                          JSGeneratorObject* generator);
-  void ExtractFixedArrayReferences(HeapEntry* entry, FixedArray* array);
+                                          JSGeneratorObject generator);
+  void ExtractFixedArrayReferences(HeapEntry* entry, FixedArray array);
   void ExtractFeedbackVectorReferences(HeapEntry* entry,
-                                       FeedbackVector* feedback_vector);
+                                       FeedbackVector feedback_vector);
+  void ExtractDescriptorArrayReferences(HeapEntry* entry,
+                                        DescriptorArray array);
   template <typename T>
-  void ExtractWeakArrayReferences(int header_size, HeapEntry* entry, T* array);
-  void ExtractPropertyReferences(JSObject* js_obj, HeapEntry* entry);
-  void ExtractAccessorPairProperty(HeapEntry* entry, Name* key,
-                                   Object* callback_obj, int field_offset = -1);
-  void ExtractElementReferences(JSObject* js_obj, HeapEntry* entry);
-  void ExtractInternalReferences(JSObject* js_obj, HeapEntry* entry);
-
-  bool IsEssentialObject(Object* object);
-  bool IsEssentialHiddenReference(Object* parent, int field_offset);
-
-  void SetContextReference(HeapEntry* parent_entry, String* reference_name,
-                           Object* child, int field_offset);
+  void ExtractWeakArrayReferences(int header_size, HeapEntry* entry, T array);
+  void ExtractPropertyReferences(JSObject js_obj, HeapEntry* entry);
+  void ExtractAccessorPairProperty(HeapEntry* entry, Name key,
+                                   Object callback_obj, int field_offset = -1);
+  void ExtractElementReferences(JSObject js_obj, HeapEntry* entry);
+  void ExtractInternalReferences(JSObject js_obj, HeapEntry* entry);
+
+  bool IsEssentialObject(Object object);
+  bool IsEssentialHiddenReference(Object parent, int field_offset);
+
+  void SetContextReference(HeapEntry* parent_entry, String reference_name,
+                           Object child, int field_offset);
   void SetNativeBindReference(HeapEntry* parent_entry,
-                              const char* reference_name, Object* child);
-  void SetElementReference(HeapEntry* parent_entry, int index, Object* child);
+                              const char* reference_name, Object child);
+  void SetElementReference(HeapEntry* parent_entry, int index, Object child);
   void SetInternalReference(HeapEntry* parent_entry, const char* reference_name,
-                            Object* child, int field_offset = -1);
-  void SetInternalReference(HeapEntry* parent_entry, int index, Object* child,
+                            Object child, int field_offset = -1);
+  void SetInternalReference(HeapEntry* parent_entry, int index, Object child,
                             int field_offset = -1);
-  void SetHiddenReference(HeapObject* parent_obj, HeapEntry* parent_entry,
-                          int index, Object* child, int field_offset);
+  void SetHiddenReference(HeapObject parent_obj, HeapEntry* parent_entry,
+                          int index, Object child, int field_offset);
   void SetWeakReference(HeapEntry* parent_entry, const char* reference_name,
-                        Object* child_obj, int field_offset);
-  void SetWeakReference(HeapEntry* parent_entry, int index, Object* child_obj,
+                        Object child_obj, int field_offset);
+  void SetWeakReference(HeapEntry* parent_entry, int index, Object child_obj,
                         int field_offset);
-  void SetPropertyReference(HeapEntry* parent_entry, Name* reference_name,
-                            Object* child,
+  void SetPropertyReference(HeapEntry* parent_entry, Name reference_name,
+                            Object child,
                             const char* name_format_string = nullptr,
                             int field_offset = -1);
   void SetDataOrAccessorPropertyReference(
-      PropertyKind kind, HeapEntry* parent_entry, Name* reference_name,
-      Object* child, const char* name_format_string = nullptr,
+      PropertyKind kind, HeapEntry* parent_entry, Name reference_name,
+      Object child, const char* name_format_string = nullptr,
       int field_offset = -1);
 
-  void SetUserGlobalReference(Object* user_global);
+  void SetUserGlobalReference(Object user_global);
   void SetRootGcRootsReference();
   void SetGcRootsReference(Root root);
   void SetGcSubrootReference(Root root, const char* description, bool is_weak,
-                             Object* child);
-  const char* GetStrongGcSubrootName(Object* object);
-  void TagObject(Object* obj, const char* tag);
+                             Object child);
+  const char* GetStrongGcSubrootName(Object object);
+  void TagObject(Object obj, const char* tag);
 
-  HeapEntry* GetEntry(Object* obj);
+  HeapEntry* GetEntry(Object obj);
 
   Heap* heap_;
   HeapSnapshot* snapshot_;
@@ -429,9 +430,10 @@ class V8HeapExplorer : public HeapEntriesAllocator {
   HeapObjectsMap* heap_object_map_;
   SnapshottingProgressReportingInterface* progress_;
   HeapSnapshotGenerator* generator_ = nullptr;
-  std::unordered_map<JSGlobalObject*, const char*> objects_tags_;
-  std::unordered_map<Object*, const char*> strong_gc_subroot_names_;
-  std::unordered_set<JSGlobalObject*> user_roots_;
+  std::unordered_map<JSGlobalObject, const char*, Object::Hasher> objects_tags_;
+  std::unordered_map<Object, const char*, Object::Hasher>
+      strong_gc_subroot_names_;
+  std::unordered_set<JSGlobalObject, Object::Hasher> user_roots_;
   v8::HeapProfiler::ObjectNameResolver* global_object_name_resolver_;
 
   std::vector<bool> visited_fields_;
@@ -458,13 +460,13 @@ class NativeObjectsExplorer {
  private:
   void FillRetainedObjects();
   void FillEdges();
-  std::vector<HeapObject*>* GetVectorMaybeDisposeInfo(
+  std::vector<HeapObject>* GetVectorMaybeDisposeInfo(
       v8::RetainedObjectInfo* info);
   void SetNativeRootReference(v8::RetainedObjectInfo* info);
   void SetRootNativeRootsReference();
-  void SetWrapperNativeReferences(HeapObject* wrapper,
-                                      v8::RetainedObjectInfo* info);
-  void VisitSubtreeWrapper(Object** p, uint16_t class_id);
+  void SetWrapperNativeReferences(HeapObject wrapper,
+                                  v8::RetainedObjectInfo* info);
+  void VisitSubtreeWrapper(Handle<Object> p, uint16_t class_id);
 
   struct RetainedInfoHasher {
     std::size_t operator()(v8::RetainedObjectInfo* info) const {
@@ -486,8 +488,8 @@ class NativeObjectsExplorer {
   HeapSnapshot* snapshot_;
   StringsStorage* names_;
   bool embedder_queried_;
-  std::unordered_set<Object*> in_groups_;
-  std::unordered_map<v8::RetainedObjectInfo*, std::vector<HeapObject*>*,
+  std::unordered_set<Object, Object::Hasher> in_groups_;
+  std::unordered_map<v8::RetainedObjectInfo*, std::vector<HeapObject>*,
                      RetainedInfoHasher, RetainedInfoEquals>
       objects_by_info_;
   std::unordered_map<const char*, NativeGroupRetainedObjectInfo*,
diff --git a/deps/v8/src/profiler/profile-generator.cc b/deps/v8/src/profiler/profile-generator.cc
index d60da5a44d..8ce9fb392e 100644
--- a/deps/v8/src/profiler/profile-generator.cc
+++ b/deps/v8/src/profiler/profile-generator.cc
@@ -18,7 +18,8 @@
 namespace v8 {
 namespace internal {
 
-void SourcePositionTable::SetPosition(int pc_offset, int line) {
+void SourcePositionTable::SetPosition(int pc_offset, int line,
+                                      int inlining_id) {
   DCHECK_GE(pc_offset, 0);
   DCHECK_GT(line, 0);  // The 1-based number of the source line.
   // Check that we are inserting in ascending order, so that the vector remains
@@ -26,8 +27,9 @@ void SourcePositionTable::SetPosition(int pc_offset, int line) {
   DCHECK(pc_offsets_to_lines_.empty() ||
          pc_offsets_to_lines_.back().pc_offset < pc_offset);
   if (pc_offsets_to_lines_.empty() ||
-      pc_offsets_to_lines_.back().line_number != line) {
-    pc_offsets_to_lines_.push_back({pc_offset, line});
+      pc_offsets_to_lines_.back().line_number != line ||
+      pc_offsets_to_lines_.back().inlining_id != inlining_id) {
+    pc_offsets_to_lines_.push_back({pc_offset, line, inlining_id});
   }
 }
 
@@ -35,13 +37,33 @@ int SourcePositionTable::GetSourceLineNumber(int pc_offset) const {
   if (pc_offsets_to_lines_.empty()) {
     return v8::CpuProfileNode::kNoLineNumberInfo;
   }
-  auto it =
-      std::upper_bound(pc_offsets_to_lines_.begin(), pc_offsets_to_lines_.end(),
-                       PCOffsetAndLineNumber{pc_offset, 0});
+  auto it = std::lower_bound(
+      pc_offsets_to_lines_.begin(), pc_offsets_to_lines_.end(),
+      SourcePositionTuple{pc_offset, 0, SourcePosition::kNotInlined});
   if (it != pc_offsets_to_lines_.begin()) --it;
   return it->line_number;
 }
 
+int SourcePositionTable::GetInliningId(int pc_offset) const {
+  if (pc_offsets_to_lines_.empty()) {
+    return SourcePosition::kNotInlined;
+  }
+  auto it = std::lower_bound(
+      pc_offsets_to_lines_.begin(), pc_offsets_to_lines_.end(),
+      SourcePositionTuple{pc_offset, 0, SourcePosition::kNotInlined});
+  if (it != pc_offsets_to_lines_.begin()) --it;
+  return it->inlining_id;
+}
+
+void SourcePositionTable::print() const {
+  base::OS::Print(" - source position table at %p\n", this);
+  for (const SourcePositionTuple& pos_info : pc_offsets_to_lines_) {
+    base::OS::Print("    %d --> line_number: %d inlining_id: %d\n",
+                    pos_info.pc_offset, pos_info.line_number,
+                    pos_info.inlining_id);
+  }
+}
+
 const char* const CodeEntry::kWasmResourceNamePrefix = "wasm ";
 const char* const CodeEntry::kEmptyResourceName = "";
 const char* const CodeEntry::kEmptyBailoutReason = "";
@@ -66,20 +88,22 @@ base::LazyDynamicInstance<CodeEntry,
     CodeEntry::kUnresolvedEntry = LAZY_DYNAMIC_INSTANCE_INITIALIZER;
 
 CodeEntry* CodeEntry::ProgramEntryCreateTrait::Create() {
-  return new CodeEntry(Logger::FUNCTION_TAG, CodeEntry::kProgramEntryName);
+  return new CodeEntry(CodeEventListener::FUNCTION_TAG,
+                       CodeEntry::kProgramEntryName);
 }
 
 CodeEntry* CodeEntry::IdleEntryCreateTrait::Create() {
-  return new CodeEntry(Logger::FUNCTION_TAG, CodeEntry::kIdleEntryName);
+  return new CodeEntry(CodeEventListener::FUNCTION_TAG,
+                       CodeEntry::kIdleEntryName);
 }
 
 CodeEntry* CodeEntry::GCEntryCreateTrait::Create() {
-  return new CodeEntry(Logger::BUILTIN_TAG,
+  return new CodeEntry(CodeEventListener::BUILTIN_TAG,
                        CodeEntry::kGarbageCollectorEntryName);
 }
 
 CodeEntry* CodeEntry::UnresolvedEntryCreateTrait::Create() {
-  return new CodeEntry(Logger::FUNCTION_TAG,
+  return new CodeEntry(CodeEventListener::FUNCTION_TAG,
                        CodeEntry::kUnresolvedFunctionName);
 }
 
@@ -119,17 +143,25 @@ int CodeEntry::GetSourceLine(int pc_offset) const {
   return v8::CpuProfileNode::kNoLineNumberInfo;
 }
 
-void CodeEntry::AddInlineStack(
-    int pc_offset, std::vector<std::unique_ptr<CodeEntry>> inline_stack) {
-  EnsureRareData()->inline_locations_.insert(
-      std::make_pair(pc_offset, std::move(inline_stack)));
+void CodeEntry::SetInlineStacks(
+    std::unordered_set<std::unique_ptr<CodeEntry>, Hasher, Equals>
+        inline_entries,
+    std::unordered_map<int, std::vector<CodeEntryAndLineNumber>>
+        inline_stacks) {
+  EnsureRareData()->inline_entries_ = std::move(inline_entries);
+  rare_data_->inline_stacks_ = std::move(inline_stacks);
 }
 
-const std::vector<std::unique_ptr<CodeEntry>>* CodeEntry::GetInlineStack(
+const std::vector<CodeEntryAndLineNumber>* CodeEntry::GetInlineStack(
     int pc_offset) const {
-  if (!rare_data_) return nullptr;
-  auto it = rare_data_->inline_locations_.find(pc_offset);
-  return it != rare_data_->inline_locations_.end() ? &it->second : nullptr;
+  if (!line_info_) return nullptr;
+
+  int inlining_id = line_info_->GetInliningId(pc_offset);
+  if (inlining_id == SourcePosition::kNotInlined) return nullptr;
+  DCHECK(rare_data_);
+
+  auto it = rare_data_->inline_stacks_.find(inlining_id);
+  return it != rare_data_->inline_stacks_.end() ? &it->second : nullptr;
 }
 
 void CodeEntry::set_deopt_info(
@@ -142,9 +174,9 @@ void CodeEntry::set_deopt_info(
   rare_data->deopt_inlined_frames_ = std::move(inlined_frames);
 }
 
-void CodeEntry::FillFunctionInfo(SharedFunctionInfo* shared) {
+void CodeEntry::FillFunctionInfo(SharedFunctionInfo shared) {
   if (!shared->script()->IsScript()) return;
-  Script* script = Script::cast(shared->script());
+  Script script = Script::cast(shared->script());
   set_script_id(script->id());
   set_position(shared->StartPosition());
   if (shared->optimization_disabled()) {
@@ -174,6 +206,55 @@ CodeEntry::RareData* CodeEntry::EnsureRareData() {
   return rare_data_.get();
 }
 
+void CodeEntry::print() const {
+  base::OS::Print("CodeEntry: at %p\n", this);
+
+  base::OS::Print(" - name: %s\n", name_);
+  base::OS::Print(" - resource_name: %s\n", resource_name_);
+  base::OS::Print(" - line_number: %d\n", line_number_);
+  base::OS::Print(" - column_number: %d\n", column_number_);
+  base::OS::Print(" - script_id: %d\n", script_id_);
+  base::OS::Print(" - position: %d\n", position_);
+  base::OS::Print(" - instruction_start: %p\n",
+                  reinterpret_cast<void*>(instruction_start_));
+
+  if (line_info_) {
+    line_info_->print();
+  }
+
+  if (rare_data_) {
+    base::OS::Print(" - deopt_reason: %s\n", rare_data_->deopt_reason_);
+    base::OS::Print(" - bailout_reason: %s\n", rare_data_->bailout_reason_);
+    base::OS::Print(" - deopt_id: %d\n", rare_data_->deopt_id_);
+
+    if (!rare_data_->inline_stacks_.empty()) {
+      base::OS::Print(" - inline stacks:\n");
+      for (auto it = rare_data_->inline_stacks_.begin();
+           it != rare_data_->inline_stacks_.end(); it++) {
+        base::OS::Print("    inlining_id: [%d]\n", it->first);
+        for (const auto& e : it->second) {
+          base::OS::Print("     %s --> %d\n", e.code_entry->name(),
+                          e.line_number);
+        }
+      }
+    } else {
+      base::OS::Print(" - inline stacks: (empty)\n");
+    }
+
+    if (!rare_data_->deopt_inlined_frames_.empty()) {
+      base::OS::Print(" - deopt inlined frames:\n");
+      for (const CpuProfileDeoptFrame& frame :
+           rare_data_->deopt_inlined_frames_) {
+        base::OS::Print("script_id: %d position: %zu\n", frame.script_id,
+                        frame.position);
+      }
+    } else {
+      base::OS::Print(" - deopt inlined frames: (empty)\n");
+    }
+  }
+  base::OS::Print("\n");
+}
+
 void ProfileNode::CollectDeoptInfo(CodeEntry* entry) {
   deopt_infos_.push_back(entry->GetDeoptInfo());
   entry->clear_deopt_info();
@@ -759,15 +840,22 @@ void ProfileGenerator::RecordTickSample(const TickSample& sample) {
         int pc_offset =
             static_cast<int>(stack_pos - entry->instruction_start());
         // TODO(petermarshall): pc_offset can still be negative in some cases.
-        const std::vector<std::unique_ptr<CodeEntry>>* inline_stack =
+        const std::vector<CodeEntryAndLineNumber>* inline_stack =
             entry->GetInlineStack(pc_offset);
         if (inline_stack) {
-          std::transform(
-              inline_stack->rbegin(), inline_stack->rend(),
-              std::back_inserter(stack_trace),
-              [=](const std::unique_ptr<CodeEntry>& ptr) {
-                return CodeEntryAndLineNumber{ptr.get(), no_line_info};
-              });
+          int most_inlined_frame_line_number = entry->GetSourceLine(pc_offset);
+          stack_trace.insert(stack_trace.end(), inline_stack->begin(),
+                             inline_stack->end());
+          // This is a bit of a messy hack. The line number for the most-inlined
+          // frame (the function at the end of the chain of function calls) has
+          // the wrong line number in inline_stack. The actual line number in
+          // this function is stored in the SourcePositionTable in entry. We fix
+          // up the line number for the most-inlined frame here.
+          // TODO(petermarshall): Remove this and use a tree with a node per
+          // inlining_id.
+          DCHECK(!inline_stack->empty());
+          size_t index = stack_trace.size() - inline_stack->size();
+          stack_trace[index].line_number = most_inlined_frame_line_number;
         }
         // Skip unresolved frames (e.g. internal frame) and get source line of
         // the first JS caller.
@@ -779,6 +867,12 @@ void ProfileGenerator::RecordTickSample(const TickSample& sample) {
           src_line_not_found = false;
         }
         line_number = entry->GetSourceLine(pc_offset);
+
+        // The inline stack contains the top-level function i.e. the same
+        // function as entry. We don't want to add it twice. The one from the
+        // inline stack has the correct line number for this particular inlining
+        // so we use it instead of pushing entry to stack_trace.
+        if (inline_stack) continue;
       }
       stack_trace.push_back({entry, line_number});
     }
diff --git a/deps/v8/src/profiler/profile-generator.h b/deps/v8/src/profiler/profile-generator.h
index ac9506ab21..ebb4f0ea2c 100644
--- a/deps/v8/src/profiler/profile-generator.h
+++ b/deps/v8/src/profiler/profile-generator.h
@@ -16,7 +16,8 @@
 
 #include "include/v8-profiler.h"
 #include "src/allocation.h"
-#include "src/log.h"
+#include "src/builtins/builtins.h"
+#include "src/code-events.h"
 #include "src/profiler/strings-storage.h"
 #include "src/source-position.h"
 
@@ -26,29 +27,35 @@ namespace internal {
 struct TickSample;
 
 // Provides a mapping from the offsets within generated code or a bytecode array
-// to the source line.
+// to the source line and inlining id.
 class SourcePositionTable : public Malloced {
  public:
   SourcePositionTable() = default;
 
-  void SetPosition(int pc_offset, int line);
+  void SetPosition(int pc_offset, int line, int inlining_id);
   int GetSourceLineNumber(int pc_offset) const;
+  int GetInliningId(int pc_offset) const;
+
+  void print() const;
 
  private:
-  struct PCOffsetAndLineNumber {
-    bool operator<(const PCOffsetAndLineNumber& other) const {
+  struct SourcePositionTuple {
+    bool operator<(const SourcePositionTuple& other) const {
       return pc_offset < other.pc_offset;
     }
     int pc_offset;
     int line_number;
+    int inlining_id;
   };
-  // This is logically a map, but we store it as a vector of pairs, sorted by
+  // This is logically a map, but we store it as a vector of tuples, sorted by
   // the pc offset, so that we can save space and look up items using binary
   // search.
-  std::vector<PCOffsetAndLineNumber> pc_offsets_to_lines_;
+  std::vector<SourcePositionTuple> pc_offsets_to_lines_;
   DISALLOW_COPY_AND_ASSIGN(SourcePositionTable);
 };
 
+struct CodeEntryAndLineNumber;
+
 class CodeEntry {
  public:
   // CodeEntry doesn't own name strings, just references them.
@@ -91,7 +98,7 @@ class CodeEntry {
   void mark_used() { bit_field_ = UsedField::update(bit_field_, true); }
   bool used() const { return UsedField::decode(bit_field_); }
 
-  void FillFunctionInfo(SharedFunctionInfo* shared);
+  void FillFunctionInfo(SharedFunctionInfo shared);
 
   void SetBuiltinId(Builtins::Name id);
   Builtins::Name builtin_id() const {
@@ -103,9 +110,24 @@ class CodeEntry {
 
   int GetSourceLine(int pc_offset) const;
 
-  void AddInlineStack(int pc_offset,
-                      std::vector<std::unique_ptr<CodeEntry>> inline_stack);
-  const std::vector<std::unique_ptr<CodeEntry>>* GetInlineStack(
+  struct Equals {
+    bool operator()(const std::unique_ptr<CodeEntry>& lhs,
+                    const std::unique_ptr<CodeEntry>& rhs) const {
+      return lhs.get()->IsSameFunctionAs(rhs.get());
+    }
+  };
+  struct Hasher {
+    std::size_t operator()(const std::unique_ptr<CodeEntry>& e) const {
+      return e->GetHash();
+    }
+  };
+
+  void SetInlineStacks(
+      std::unordered_set<std::unique_ptr<CodeEntry>, Hasher, Equals>
+          inline_entries,
+      std::unordered_map<int, std::vector<CodeEntryAndLineNumber>>
+          inline_stacks);
+  const std::vector<CodeEntryAndLineNumber>* GetInlineStack(
       int pc_offset) const;
 
   void set_instruction_start(Address start) { instruction_start_ = start; }
@@ -136,13 +158,16 @@ class CodeEntry {
     return kUnresolvedEntry.Pointer();
   }
 
+  void print() const;
+
  private:
   struct RareData {
     const char* deopt_reason_ = kNoDeoptReason;
     const char* bailout_reason_ = kEmptyBailoutReason;
     int deopt_id_ = kNoDeoptimizationId;
-    std::unordered_map<int, std::vector<std::unique_ptr<CodeEntry>>>
-        inline_locations_;
+    std::unordered_map<int, std::vector<CodeEntryAndLineNumber>> inline_stacks_;
+    std::unordered_set<std::unique_ptr<CodeEntry>, Hasher, Equals>
+        inline_entries_;
     std::vector<CpuProfileDeoptFrame> deopt_inlined_frames_;
   };
 
@@ -170,7 +195,7 @@ class CodeEntry {
   static base::LazyDynamicInstance<CodeEntry, UnresolvedEntryCreateTrait>::type
       kUnresolvedEntry;
 
-  using TagField = BitField<Logger::LogEventsAndTags, 0, 8>;
+  using TagField = BitField<CodeEventListener::LogEventsAndTags, 0, 8>;
   using BuiltinIdField = BitField<Builtins::Name, 8, 23>;
   using UsedField = BitField<bool, 31, 1>;
 
@@ -313,6 +338,7 @@ class ProfileTree {
   DISALLOW_COPY_AND_ASSIGN(ProfileTree);
 };
 
+class CpuProfiler;
 
 class CpuProfile {
  public:
@@ -412,7 +438,7 @@ class CpuProfilesCollection {
   std::vector<std::unique_ptr<CpuProfile>>* profiles() {
     return &finished_profiles_;
   }
-  const char* GetName(Name* name) { return resource_names_.GetName(name); }
+  const char* GetName(Name name) { return resource_names_.GetName(name); }
   bool IsLastProfile(const char* title);
   void RemoveProfile(CpuProfile* profile);
 
diff --git a/deps/v8/src/profiler/profiler-listener.cc b/deps/v8/src/profiler/profiler-listener.cc
index f90a2e11d3..2aac98f61f 100644
--- a/deps/v8/src/profiler/profiler-listener.cc
+++ b/deps/v8/src/profiler/profiler-listener.cc
@@ -5,10 +5,11 @@
 #include "src/profiler/profiler-listener.h"
 
 #include "src/deoptimizer.h"
-#include "src/instruction-stream.h"
 #include "src/objects-inl.h"
 #include "src/profiler/cpu-profiler.h"
 #include "src/profiler/profile-generator-inl.h"
+#include "src/reloc-info.h"
+#include "src/snapshot/embedded-data.h"
 #include "src/source-position-table.h"
 #include "src/wasm/wasm-code-manager.h"
 
@@ -21,7 +22,7 @@ ProfilerListener::ProfilerListener(Isolate* isolate,
 
 ProfilerListener::~ProfilerListener() = default;
 
-void ProfilerListener::CallbackEvent(Name* name, Address entry_point) {
+void ProfilerListener::CallbackEvent(Name name, Address entry_point) {
   CodeEventsContainer evt_rec(CodeEventRecord::CODE_CREATION);
   CodeCreateEventRecord* rec = &evt_rec.CodeCreateEventRecord_;
   rec->instruction_start = entry_point;
@@ -31,7 +32,7 @@ void ProfilerListener::CallbackEvent(Name* name, Address entry_point) {
 }
 
 void ProfilerListener::CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
-                                       AbstractCode* code, const char* name) {
+                                       AbstractCode code, const char* name) {
   CodeEventsContainer evt_rec(CodeEventRecord::CODE_CREATION);
   CodeCreateEventRecord* rec = &evt_rec.CodeCreateEventRecord_;
   rec->instruction_start = code->InstructionStart();
@@ -39,13 +40,12 @@ void ProfilerListener::CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
                             CpuProfileNode::kNoLineNumberInfo,
                             CpuProfileNode::kNoColumnNumberInfo, nullptr,
                             code->InstructionStart());
-  RecordInliningInfo(rec->entry, code);
   rec->instruction_size = code->InstructionSize();
   DispatchCodeEvent(evt_rec);
 }
 
 void ProfilerListener::CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
-                                       AbstractCode* code, Name* name) {
+                                       AbstractCode code, Name name) {
   CodeEventsContainer evt_rec(CodeEventRecord::CODE_CREATION);
   CodeCreateEventRecord* rec = &evt_rec.CodeCreateEventRecord_;
   rec->instruction_start = code->InstructionStart();
@@ -53,15 +53,14 @@ void ProfilerListener::CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
                             CpuProfileNode::kNoLineNumberInfo,
                             CpuProfileNode::kNoColumnNumberInfo, nullptr,
                             code->InstructionStart());
-  RecordInliningInfo(rec->entry, code);
   rec->instruction_size = code->InstructionSize();
   DispatchCodeEvent(evt_rec);
 }
 
 void ProfilerListener::CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
-                                       AbstractCode* code,
-                                       SharedFunctionInfo* shared,
-                                       Name* script_name) {
+                                       AbstractCode code,
+                                       SharedFunctionInfo shared,
+                                       Name script_name) {
   CodeEventsContainer evt_rec(CodeEventRecord::CODE_CREATION);
   CodeCreateEventRecord* rec = &evt_rec.CodeCreateEventRecord_;
   rec->instruction_start = code->InstructionStart();
@@ -70,40 +69,113 @@ void ProfilerListener::CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
                             CpuProfileNode::kNoLineNumberInfo,
                             CpuProfileNode::kNoColumnNumberInfo, nullptr,
                             code->InstructionStart());
-  RecordInliningInfo(rec->entry, code);
+  DCHECK(!code->IsCode());
   rec->entry->FillFunctionInfo(shared);
   rec->instruction_size = code->InstructionSize();
   DispatchCodeEvent(evt_rec);
 }
 
+namespace {
+
+CodeEntry* GetOrInsertCachedEntry(
+    std::unordered_set<std::unique_ptr<CodeEntry>, CodeEntry::Hasher,
+                       CodeEntry::Equals>* entries,
+    std::unique_ptr<CodeEntry> search_value) {
+  auto it = entries->find(search_value);
+  if (it != entries->end()) return it->get();
+  CodeEntry* ret = search_value.get();
+  entries->insert(std::move(search_value));
+  return ret;
+}
+
+}  // namespace
+
 void ProfilerListener::CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
-                                       AbstractCode* abstract_code,
-                                       SharedFunctionInfo* shared,
-                                       Name* script_name, int line,
-                                       int column) {
+                                       AbstractCode abstract_code,
+                                       SharedFunctionInfo shared,
+                                       Name script_name, int line, int column) {
   CodeEventsContainer evt_rec(CodeEventRecord::CODE_CREATION);
   CodeCreateEventRecord* rec = &evt_rec.CodeCreateEventRecord_;
   rec->instruction_start = abstract_code->InstructionStart();
   std::unique_ptr<SourcePositionTable> line_table;
+  std::unordered_map<int, std::vector<CodeEntryAndLineNumber>> inline_stacks;
+  std::unordered_set<std::unique_ptr<CodeEntry>, CodeEntry::Hasher,
+                     CodeEntry::Equals>
+      cached_inline_entries;
   if (shared->script()->IsScript()) {
-    Script* script = Script::cast(shared->script());
+    Script script = Script::cast(shared->script());
     line_table.reset(new SourcePositionTable());
+    HandleScope scope(isolate_);
+
+    // Add each position to the source position table and store inlining stacks
+    // for inline positions. We store almost the same information in the
+    // profiler as is stored on the code object, except that we transform source
+    // positions to line numbers here, because we only care about attributing
+    // ticks to a given line.
     for (SourcePositionTableIterator it(abstract_code->source_position_table());
          !it.done(); it.Advance()) {
-      // TODO(alph,tebbi) Skipping inlined positions for now, because they might
-      // refer to a different script.
-      if (it.source_position().InliningId() != SourcePosition::kNotInlined)
-        continue;
       int position = it.source_position().ScriptOffset();
       int line_number = script->GetLineNumber(position) + 1;
-      line_table->SetPosition(it.code_offset(), line_number);
+      int inlining_id = it.source_position().InliningId();
+      line_table->SetPosition(it.code_offset(), line_number, inlining_id);
+
+      if (inlining_id != SourcePosition::kNotInlined) {
+        DCHECK(abstract_code->IsCode());
+        Code code = abstract_code->GetCode();
+        std::vector<SourcePositionInfo> stack =
+            it.source_position().InliningStack(handle(code, isolate_));
+        DCHECK(!stack.empty());
+
+        std::vector<CodeEntryAndLineNumber> inline_stack;
+        for (SourcePositionInfo& pos_info : stack) {
+          if (pos_info.position.ScriptOffset() == kNoSourcePosition) continue;
+          if (pos_info.script.is_null()) continue;
+
+          int line_number =
+              pos_info.script->GetLineNumber(pos_info.position.ScriptOffset()) +
+              1;
+
+          const char* resource_name =
+              (pos_info.script->name()->IsName())
+                  ? GetName(Name::cast(pos_info.script->name()))
+                  : CodeEntry::kEmptyResourceName;
+
+          // We need the start line number and column number of the function for
+          // kLeafNodeLineNumbers mode. Creating a SourcePositionInfo is a handy
+          // way of getting both easily.
+          SourcePositionInfo start_pos_info(
+              SourcePosition(pos_info.shared->StartPosition()),
+              pos_info.shared);
+
+          std::unique_ptr<CodeEntry> inline_entry =
+              base::make_unique<CodeEntry>(
+                  tag, GetName(pos_info.shared->DebugName()), resource_name,
+                  start_pos_info.line + 1, start_pos_info.column + 1, nullptr,
+                  code->InstructionStart());
+          inline_entry->FillFunctionInfo(*pos_info.shared);
+
+          // Create a canonical CodeEntry for each inlined frame and then re-use
+          // them for subsequent inline stacks to avoid a lot of duplication.
+          CodeEntry* cached_entry = GetOrInsertCachedEntry(
+              &cached_inline_entries, std::move(inline_entry));
+
+          inline_stack.push_back(
+              CodeEntryAndLineNumber{cached_entry, line_number});
+        }
+        DCHECK(!inline_stack.empty());
+        inline_stacks.emplace(inlining_id, std::move(inline_stack));
+      }
     }
   }
   rec->entry =
       NewCodeEntry(tag, GetName(shared->DebugName()),
                    GetName(InferScriptName(script_name, shared)), line, column,
                    std::move(line_table), abstract_code->InstructionStart());
-  RecordInliningInfo(rec->entry, abstract_code);
+  if (!inline_stacks.empty()) {
+    rec->entry->SetInlineStacks(std::move(cached_inline_entries),
+                                std::move(inline_stacks));
+  }
+
   rec->entry->FillFunctionInfo(shared);
   rec->instruction_size = abstract_code->InstructionSize();
   DispatchCodeEvent(evt_rec);
@@ -123,7 +195,7 @@ void ProfilerListener::CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
   DispatchCodeEvent(evt_rec);
 }
 
-void ProfilerListener::CodeMoveEvent(AbstractCode* from, AbstractCode* to) {
+void ProfilerListener::CodeMoveEvent(AbstractCode from, AbstractCode to) {
   CodeEventsContainer evt_rec(CodeEventRecord::CODE_MOVE);
   CodeMoveEventRecord* rec = &evt_rec.CodeMoveEventRecord_;
   rec->from_instruction_start = from->InstructionStart();
@@ -131,8 +203,8 @@ void ProfilerListener::CodeMoveEvent(AbstractCode* from, AbstractCode* to) {
   DispatchCodeEvent(evt_rec);
 }
 
-void ProfilerListener::CodeDisableOptEvent(AbstractCode* code,
-                                           SharedFunctionInfo* shared) {
+void ProfilerListener::CodeDisableOptEvent(AbstractCode code,
+                                           SharedFunctionInfo shared) {
   CodeEventsContainer evt_rec(CodeEventRecord::CODE_DISABLE_OPT);
   CodeDisableOptEventRecord* rec = &evt_rec.CodeDisableOptEventRecord_;
   rec->instruction_start = code->InstructionStart();
@@ -140,7 +212,7 @@ void ProfilerListener::CodeDisableOptEvent(AbstractCode* code,
   DispatchCodeEvent(evt_rec);
 }
 
-void ProfilerListener::CodeDeoptEvent(Code* code, DeoptimizeKind kind,
+void ProfilerListener::CodeDeoptEvent(Code code, DeoptimizeKind kind,
                                       Address pc, int fp_to_sp_delta) {
   CodeEventsContainer evt_rec(CodeEventRecord::CODE_DEOPT);
   CodeDeoptEventRecord* rec = &evt_rec.CodeDeoptEventRecord_;
@@ -157,7 +229,7 @@ void ProfilerListener::CodeDeoptEvent(Code* code, DeoptimizeKind kind,
   DispatchCodeEvent(evt_rec);
 }
 
-void ProfilerListener::GetterCallbackEvent(Name* name, Address entry_point) {
+void ProfilerListener::GetterCallbackEvent(Name name, Address entry_point) {
   CodeEventsContainer evt_rec(CodeEventRecord::CODE_CREATION);
   CodeCreateEventRecord* rec = &evt_rec.CodeCreateEventRecord_;
   rec->instruction_start = entry_point;
@@ -167,8 +239,7 @@ void ProfilerListener::GetterCallbackEvent(Name* name, Address entry_point) {
   DispatchCodeEvent(evt_rec);
 }
 
-void ProfilerListener::RegExpCodeCreateEvent(AbstractCode* code,
-                                             String* source) {
+void ProfilerListener::RegExpCodeCreateEvent(AbstractCode code, String source) {
   CodeEventsContainer evt_rec(CodeEventRecord::CODE_CREATION);
   CodeCreateEventRecord* rec = &evt_rec.CodeCreateEventRecord_;
   rec->instruction_start = code->InstructionStart();
@@ -180,7 +251,7 @@ void ProfilerListener::RegExpCodeCreateEvent(AbstractCode* code,
   DispatchCodeEvent(evt_rec);
 }
 
-void ProfilerListener::SetterCallbackEvent(Name* name, Address entry_point) {
+void ProfilerListener::SetterCallbackEvent(Name name, Address entry_point) {
   CodeEventsContainer evt_rec(CodeEventRecord::CODE_CREATION);
   CodeCreateEventRecord* rec = &evt_rec.CodeCreateEventRecord_;
   rec->instruction_start = entry_point;
@@ -190,67 +261,14 @@ void ProfilerListener::SetterCallbackEvent(Name* name, Address entry_point) {
   DispatchCodeEvent(evt_rec);
 }
 
-Name* ProfilerListener::InferScriptName(Name* name, SharedFunctionInfo* info) {
+Name ProfilerListener::InferScriptName(Name name, SharedFunctionInfo info) {
   if (name->IsString() && String::cast(name)->length()) return name;
   if (!info->script()->IsScript()) return name;
-  Object* source_url = Script::cast(info->script())->source_url();
+  Object source_url = Script::cast(info->script())->source_url();
   return source_url->IsName() ? Name::cast(source_url) : name;
 }
 
-void ProfilerListener::RecordInliningInfo(CodeEntry* entry,
-                                          AbstractCode* abstract_code) {
-  if (!abstract_code->IsCode()) return;
-  Code* code = abstract_code->GetCode();
-  if (code->kind() != Code::OPTIMIZED_FUNCTION) return;
-  DeoptimizationData* deopt_input_data =
-      DeoptimizationData::cast(code->deoptimization_data());
-  int deopt_count = deopt_input_data->DeoptCount();
-  for (int i = 0; i < deopt_count; i++) {
-    int pc_offset = deopt_input_data->Pc(i)->value();
-    if (pc_offset == -1) continue;
-    int translation_index = deopt_input_data->TranslationIndex(i)->value();
-    TranslationIterator it(deopt_input_data->TranslationByteArray(),
-                           translation_index);
-    Translation::Opcode opcode = static_cast<Translation::Opcode>(it.Next());
-    DCHECK_EQ(Translation::BEGIN, opcode);
-    it.Skip(Translation::NumberOfOperandsFor(opcode));
-    int depth = 0;
-    std::vector<std::unique_ptr<CodeEntry>> inline_stack;
-    while (it.HasNext() &&
-           Translation::BEGIN !=
-               (opcode = static_cast<Translation::Opcode>(it.Next()))) {
-      if (opcode != Translation::INTERPRETED_FRAME) {
-        it.Skip(Translation::NumberOfOperandsFor(opcode));
-        continue;
-      }
-      it.Next();  // Skip ast_id
-      int shared_info_id = it.Next();
-      it.Next();  // Skip height
-      SharedFunctionInfo* shared_info = SharedFunctionInfo::cast(
-          deopt_input_data->LiteralArray()->get(shared_info_id));
-      if (!depth++) continue;  // Skip the current function itself.
-
-      const char* resource_name =
-          (shared_info->script()->IsScript() &&
-           Script::cast(shared_info->script())->name()->IsName())
-              ? GetName(Name::cast(Script::cast(shared_info->script())->name()))
-              : CodeEntry::kEmptyResourceName;
-
-      CodeEntry* inline_entry =
-          new CodeEntry(entry->tag(), GetName(shared_info->DebugName()),
-                        resource_name, CpuProfileNode::kNoLineNumberInfo,
-                        CpuProfileNode::kNoColumnNumberInfo, nullptr,
-                        code->InstructionStart());
-      inline_entry->FillFunctionInfo(shared_info);
-      inline_stack.emplace_back(inline_entry);
-    }
-    if (!inline_stack.empty()) {
-      entry->AddInlineStack(pc_offset, std::move(inline_stack));
-    }
-  }
-}
-
-void ProfilerListener::AttachDeoptInlinedFrames(Code* code,
+void ProfilerListener::AttachDeoptInlinedFrames(Code code,
                                                 CodeDeoptEventRecord* rec) {
   int deopt_id = rec->deopt_id;
   SourcePosition last_position = SourcePosition::Unknown();
diff --git a/deps/v8/src/profiler/profiler-listener.h b/deps/v8/src/profiler/profiler-listener.h
index 51fba18a60..6bd794df70 100644
--- a/deps/v8/src/profiler/profiler-listener.h
+++ b/deps/v8/src/profiler/profiler-listener.h
@@ -28,30 +28,30 @@ class ProfilerListener : public CodeEventListener {
   ProfilerListener(Isolate*, CodeEventObserver*);
   ~ProfilerListener() override;
 
-  void CallbackEvent(Name* name, Address entry_point) override;
+  void CallbackEvent(Name name, Address entry_point) override;
   void CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
-                       AbstractCode* code, const char* comment) override;
+                       AbstractCode code, const char* comment) override;
   void CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
-                       AbstractCode* code, Name* name) override;
+                       AbstractCode code, Name name) override;
   void CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
-                       AbstractCode* code, SharedFunctionInfo* shared,
-                       Name* script_name) override;
+                       AbstractCode code, SharedFunctionInfo shared,
+                       Name script_name) override;
   void CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
-                       AbstractCode* code, SharedFunctionInfo* shared,
-                       Name* script_name, int line, int column) override;
+                       AbstractCode code, SharedFunctionInfo shared,
+                       Name script_name, int line, int column) override;
   void CodeCreateEvent(CodeEventListener::LogEventsAndTags tag,
                        const wasm::WasmCode* code,
                        wasm::WasmName name) override;
 
   void CodeMovingGCEvent() override {}
-  void CodeMoveEvent(AbstractCode* from, AbstractCode* to) override;
-  void CodeDisableOptEvent(AbstractCode* code,
-                           SharedFunctionInfo* shared) override;
-  void CodeDeoptEvent(Code* code, DeoptimizeKind kind, Address pc,
+  void CodeMoveEvent(AbstractCode from, AbstractCode to) override;
+  void CodeDisableOptEvent(AbstractCode code,
+                           SharedFunctionInfo shared) override;
+  void CodeDeoptEvent(Code code, DeoptimizeKind kind, Address pc,
                       int fp_to_sp_delta) override;
-  void GetterCallbackEvent(Name* name, Address entry_point) override;
-  void RegExpCodeCreateEvent(AbstractCode* code, String* source) override;
-  void SetterCallbackEvent(Name* name, Address entry_point) override;
+  void GetterCallbackEvent(Name name, Address entry_point) override;
+  void RegExpCodeCreateEvent(AbstractCode code, String source) override;
+  void SetterCallbackEvent(Name name, Address entry_point) override;
   void SharedFunctionInfoMoveEvent(Address from, Address to) override {}
 
   CodeEntry* NewCodeEntry(
@@ -62,7 +62,7 @@ class ProfilerListener : public CodeEventListener {
       std::unique_ptr<SourcePositionTable> line_info = nullptr,
       Address instruction_start = kNullAddress);
 
-  const char* GetName(Name* name) {
+  const char* GetName(Name name) {
     return function_and_resource_names_.GetName(name);
   }
   const char* GetName(int args_count) {
@@ -71,14 +71,13 @@ class ProfilerListener : public CodeEventListener {
   const char* GetName(const char* name) {
     return function_and_resource_names_.GetCopy(name);
   }
-  const char* GetConsName(const char* prefix, Name* name) {
+  const char* GetConsName(const char* prefix, Name name) {
     return function_and_resource_names_.GetConsName(prefix, name);
   }
 
  private:
-  void RecordInliningInfo(CodeEntry* entry, AbstractCode* abstract_code);
-  void AttachDeoptInlinedFrames(Code* code, CodeDeoptEventRecord* rec);
-  Name* InferScriptName(Name* name, SharedFunctionInfo* info);
+  void AttachDeoptInlinedFrames(Code code, CodeDeoptEventRecord* rec);
+  Name InferScriptName(Name name, SharedFunctionInfo info);
   V8_INLINE void DispatchCodeEvent(const CodeEventsContainer& evt_rec) {
     observer_->CodeEventHandler(evt_rec);
   }
diff --git a/deps/v8/src/profiler/sampling-heap-profiler.cc b/deps/v8/src/profiler/sampling-heap-profiler.cc
index 2e07135d85..3e158544fd 100644
--- a/deps/v8/src/profiler/sampling-heap-profiler.cc
+++ b/deps/v8/src/profiler/sampling-heap-profiler.cc
@@ -31,8 +31,8 @@ intptr_t SamplingAllocationObserver::GetNextSampleInterval(uint64_t rate) {
   }
   double u = random_->NextDouble();
   double next = (-base::ieee754::log(u)) * rate;
-  return next < kPointerSize
-             ? kPointerSize
+  return next < kTaggedSize
+             ? kTaggedSize
              : (next > INT_MAX ? INT_MAX : static_cast<intptr_t>(next));
 }
 
@@ -44,7 +44,7 @@ intptr_t SamplingAllocationObserver::GetNextSampleInterval(uint64_t rate) {
 // approximate the true number of allocations with size *size* given that
 // *count* samples were observed.
 v8::AllocationProfile::Allocation SamplingHeapProfiler::ScaleSample(
-    size_t size, unsigned int count) {
+    size_t size, unsigned int count) const {
   double scale = 1.0 / (1.0 - std::exp(-static_cast<double>(size) / rate_));
   // Round count instead of truncating.
   return {size, static_cast<unsigned int>(count * scale + 0.5)};
@@ -62,40 +62,39 @@ SamplingHeapProfiler::SamplingHeapProfiler(
           heap_, static_cast<intptr_t>(rate), rate, this,
           heap->isolate()->random_number_generator())),
       names_(names),
-      profile_root_(nullptr, "(root)", v8::UnboundScript::kNoScriptId, 0),
+      profile_root_(nullptr, "(root)", v8::UnboundScript::kNoScriptId, 0,
+                    next_node_id()),
       stack_depth_(stack_depth),
       rate_(rate),
       flags_(flags) {
   CHECK_GT(rate_, 0u);
-
   heap_->AddAllocationObserversToAllSpaces(other_spaces_observer_.get(),
                                            new_space_observer_.get());
 }
 
-
 SamplingHeapProfiler::~SamplingHeapProfiler() {
   heap_->RemoveAllocationObserversFromAllSpaces(other_spaces_observer_.get(),
                                                 new_space_observer_.get());
 }
 
-
 void SamplingHeapProfiler::SampleObject(Address soon_object, size_t size) {
   DisallowHeapAllocation no_allocation;
 
   HandleScope scope(isolate_);
-  HeapObject* heap_object = HeapObject::FromAddress(soon_object);
+  HeapObject heap_object = HeapObject::FromAddress(soon_object);
   Handle<Object> obj(heap_object, isolate_);
 
   // Mark the new block as FreeSpace to make sure the heap is iterable while we
   // are taking the sample.
-  heap()->CreateFillerObjectAt(soon_object, static_cast<int>(size),
-                               ClearRecordedSlots::kNo);
+  heap_->CreateFillerObjectAt(soon_object, static_cast<int>(size),
+                              ClearRecordedSlots::kNo);
 
   Local<v8::Value> loc = v8::Utils::ToLocal(obj);
 
   AllocationNode* node = AddStack();
   node->allocations_[size]++;
-  auto sample = base::make_unique<Sample>(size, node, loc, this);
+  auto sample =
+      base::make_unique<Sample>(size, node, loc, this, next_sample_id());
   sample->global.SetWeak(sample.get(), OnWeakCallback,
                          WeakCallbackType::kParameter);
 #if __clang__
@@ -132,25 +131,25 @@ void SamplingHeapProfiler::OnWeakCallback(
   // sample is deleted because its unique ptr was erased from samples_.
 }
 
-SamplingHeapProfiler::AllocationNode*
-SamplingHeapProfiler::AllocationNode::FindOrAddChildNode(const char* name,
-                                                         int script_id,
-                                                         int start_position) {
-  FunctionId id = function_id(script_id, start_position, name);
-  auto it = children_.find(id);
-  if (it != children_.end()) {
-    DCHECK_EQ(strcmp(it->second->name_, name), 0);
-    return it->second.get();
+SamplingHeapProfiler::AllocationNode* SamplingHeapProfiler::FindOrAddChildNode(
+    AllocationNode* parent, const char* name, int script_id,
+    int start_position) {
+  AllocationNode::FunctionId id =
+      AllocationNode::function_id(script_id, start_position, name);
+  AllocationNode* child = parent->FindChildNode(id);
+  if (child) {
+    DCHECK_EQ(strcmp(child->name_, name), 0);
+    return child;
   }
-  auto child =
-      base::make_unique<AllocationNode>(this, name, script_id, start_position);
-  return children_.emplace(id, std::move(child)).first->second.get();
+  auto new_child = base::make_unique<AllocationNode>(
+      parent, name, script_id, start_position, next_node_id());
+  return parent->AddChildNode(id, std::move(new_child));
 }
 
 SamplingHeapProfiler::AllocationNode* SamplingHeapProfiler::AddStack() {
   AllocationNode* node = &profile_root_;
 
-  std::vector<SharedFunctionInfo*> stack;
+  std::vector<SharedFunctionInfo> stack;
   JavaScriptFrameIterator it(isolate_);
   int frames_captured = 0;
   bool found_arguments_marker_frames = false;
@@ -162,7 +161,7 @@ SamplingHeapProfiler::AllocationNode* SamplingHeapProfiler::AddStack() {
     // in the top frames of the stack). The allocations made in this
     // sensitive moment belong to the formerly optimized frame anyway.
     if (frame->unchecked_function()->IsJSFunction()) {
-      SharedFunctionInfo* shared = frame->function()->shared();
+      SharedFunctionInfo shared = frame->function()->shared();
       stack.push_back(shared);
       frames_captured++;
     } else {
@@ -199,25 +198,25 @@ SamplingHeapProfiler::AllocationNode* SamplingHeapProfiler::AddStack() {
         name = "(JS)";
         break;
     }
-    return node->FindOrAddChildNode(name, v8::UnboundScript::kNoScriptId, 0);
+    return FindOrAddChildNode(node, name, v8::UnboundScript::kNoScriptId, 0);
   }
 
   // We need to process the stack in reverse order as the top of the stack is
   // the first element in the list.
   for (auto it = stack.rbegin(); it != stack.rend(); ++it) {
-    SharedFunctionInfo* shared = *it;
+    SharedFunctionInfo shared = *it;
     const char* name = this->names()->GetName(shared->DebugName());
     int script_id = v8::UnboundScript::kNoScriptId;
     if (shared->script()->IsScript()) {
-      Script* script = Script::cast(shared->script());
+      Script script = Script::cast(shared->script());
       script_id = script->id();
     }
-    node = node->FindOrAddChildNode(name, script_id, shared->StartPosition());
+    node = FindOrAddChildNode(node, name, script_id, shared->StartPosition());
   }
 
   if (found_arguments_marker_frames) {
     node =
-        node->FindOrAddChildNode("(deopt)", v8::UnboundScript::kNoScriptId, 0);
+        FindOrAddChildNode(node, "(deopt)", v8::UnboundScript::kNoScriptId, 0);
   }
 
   return node;
@@ -243,7 +242,7 @@ v8::AllocationProfile::Node* SamplingHeapProfiler::TranslateAllocationNode(
     Handle<Script> script = non_const_scripts[node->script_id_];
     if (!script.is_null()) {
       if (script->name()->IsName()) {
-        Name* name = Name::cast(script->name());
+        Name name = Name::cast(script->name());
         script_name = ToApiHandle<v8::String>(
             isolate_->factory()->InternalizeUtf8String(names_->GetName(name)));
       }
@@ -255,12 +254,12 @@ v8::AllocationProfile::Node* SamplingHeapProfiler::TranslateAllocationNode(
     allocations.push_back(ScaleSample(alloc.first, alloc.second));
   }
 
-  profile->nodes().push_back(v8::AllocationProfile::Node{
+  profile->nodes_.push_back(v8::AllocationProfile::Node{
       ToApiHandle<v8::String>(
           isolate_->factory()->InternalizeUtf8String(node->name_)),
       script_name, node->script_id_, node->script_position_, line, column,
-      std::vector<v8::AllocationProfile::Node*>(), allocations});
-  v8::AllocationProfile::Node* current = &profile->nodes().back();
+      node->id_, std::vector<v8::AllocationProfile::Node*>(), allocations});
+  v8::AllocationProfile::Node* current = &profile->nodes_.back();
   // The |children_| map may have nodes inserted into it during translation
   // because the translation may allocate strings on the JS heap that have
   // the potential to be sampled. That's ok since map iterators are not
@@ -283,14 +282,30 @@ v8::AllocationProfile* SamplingHeapProfiler::GetAllocationProfile() {
   std::map<int, Handle<Script>> scripts;
   {
     Script::Iterator iterator(isolate_);
-    while (Script* script = iterator.Next()) {
+    for (Script script = iterator.Next(); !script.is_null();
+         script = iterator.Next()) {
       scripts[script->id()] = handle(script, isolate_);
     }
   }
   auto profile = new v8::internal::AllocationProfile();
   TranslateAllocationNode(profile, &profile_root_, scripts);
+  profile->samples_ = SamplingHeapProfiler::BuildSamples();
+
   return profile;
 }
 
+const std::vector<v8::AllocationProfile::Sample>
+SamplingHeapProfiler::BuildSamples() const {
+  std::vector<v8::AllocationProfile::Sample> samples;
+  samples.reserve(samples_.size());
+  for (const auto& it : samples_) {
+    const Sample* sample = it.second.get();
+    samples.emplace_back(v8::AllocationProfile::Sample{
+        sample->owner->id_, sample->size, ScaleSample(sample->size, 1).count,
+        sample->sample_id});
+  }
+  return samples;
+}
+
 }  // namespace internal
 }  // namespace v8
diff --git a/deps/v8/src/profiler/sampling-heap-profiler.h b/deps/v8/src/profiler/sampling-heap-profiler.h
index 072c5eb677..818c33581d 100644
--- a/deps/v8/src/profiler/sampling-heap-profiler.h
+++ b/deps/v8/src/profiler/sampling-heap-profiler.h
@@ -25,62 +25,48 @@ class SamplingAllocationObserver;
 
 class AllocationProfile : public v8::AllocationProfile {
  public:
-  AllocationProfile() : nodes_() {}
+  AllocationProfile() = default;
 
   v8::AllocationProfile::Node* GetRootNode() override {
     return nodes_.size() == 0 ? nullptr : &nodes_.front();
   }
 
-  std::deque<v8::AllocationProfile::Node>& nodes() { return nodes_; }
+  const std::vector<v8::AllocationProfile::Sample>& GetSamples() override {
+    return samples_;
+  }
 
  private:
   std::deque<v8::AllocationProfile::Node> nodes_;
+  std::vector<v8::AllocationProfile::Sample> samples_;
+
+  friend class SamplingHeapProfiler;
 
   DISALLOW_COPY_AND_ASSIGN(AllocationProfile);
 };
 
 class SamplingHeapProfiler {
  public:
-  SamplingHeapProfiler(Heap* heap, StringsStorage* names, uint64_t rate,
-                       int stack_depth, v8::HeapProfiler::SamplingFlags flags);
-  ~SamplingHeapProfiler();
-
-  v8::AllocationProfile* GetAllocationProfile();
-
-  StringsStorage* names() const { return names_; }
-
-  class AllocationNode;
-
-  struct Sample {
-   public:
-    Sample(size_t size_, AllocationNode* owner_, Local<Value> local_,
-           SamplingHeapProfiler* profiler_)
-        : size(size_),
-          owner(owner_),
-          global(Global<Value>(
-              reinterpret_cast<v8::Isolate*>(profiler_->isolate_), local_)),
-          profiler(profiler_) {}
-    ~Sample() { global.Reset(); }
-    const size_t size;
-    AllocationNode* const owner;
-    Global<Value> global;
-    SamplingHeapProfiler* const profiler;
-
-   private:
-    DISALLOW_COPY_AND_ASSIGN(Sample);
-  };
-
   class AllocationNode {
    public:
+    typedef uint64_t FunctionId;
     AllocationNode(AllocationNode* parent, const char* name, int script_id,
-                   int start_position)
+                   int start_position, uint32_t id)
         : parent_(parent),
           script_id_(script_id),
           script_position_(start_position),
-          name_(name) {}
+          name_(name),
+          id_(id) {}
+
+    AllocationNode* FindChildNode(FunctionId id) {
+      auto it = children_.find(id);
+      return it != children_.end() ? it->second.get() : nullptr;
+    }
+
+    AllocationNode* AddChildNode(FunctionId id,
+                                 std::unique_ptr<AllocationNode> node) {
+      return children_.emplace(id, std::move(node)).first->second.get();
+    }
 
-   private:
-    typedef uint64_t FunctionId;
     static FunctionId function_id(int script_id, int start_position,
                                   const char* name) {
       // script_id == kNoScriptId case:
@@ -96,8 +82,8 @@ class SamplingHeapProfiler {
       DCHECK(static_cast<unsigned>(start_position) < (1u << 31));
       return (static_cast<uint64_t>(script_id) << 32) + (start_position << 1);
     }
-    AllocationNode* FindOrAddChildNode(const char* name, int script_id,
-                                       int start_position);
+
+   private:
     // TODO(alph): make use of unordered_map's here. Pay attention to
     // iterator invalidation during TranslateAllocationNode.
     std::map<size_t, unsigned int> allocations_;
@@ -106,6 +92,7 @@ class SamplingHeapProfiler {
     const int script_id_;
     const int script_position_;
     const char* const name_;
+    uint32_t id_;
     bool pinned_ = false;
 
     friend class SamplingHeapProfiler;
@@ -113,13 +100,45 @@ class SamplingHeapProfiler {
     DISALLOW_COPY_AND_ASSIGN(AllocationNode);
   };
 
- private:
-  Heap* heap() const { return heap_; }
+  struct Sample {
+    Sample(size_t size_, AllocationNode* owner_, Local<Value> local_,
+           SamplingHeapProfiler* profiler_, uint64_t sample_id)
+        : size(size_),
+          owner(owner_),
+          global(Global<Value>(
+              reinterpret_cast<v8::Isolate*>(profiler_->isolate_), local_)),
+          profiler(profiler_),
+          sample_id(sample_id) {}
+    ~Sample() { global.Reset(); }
+    const size_t size;
+    AllocationNode* const owner;
+    Global<Value> global;
+    SamplingHeapProfiler* const profiler;
+    const uint64_t sample_id;
+
+   private:
+    DISALLOW_COPY_AND_ASSIGN(Sample);
+  };
 
+  SamplingHeapProfiler(Heap* heap, StringsStorage* names, uint64_t rate,
+                       int stack_depth, v8::HeapProfiler::SamplingFlags flags);
+  ~SamplingHeapProfiler();
+
+  v8::AllocationProfile* GetAllocationProfile();
+  StringsStorage* names() const { return names_; }
+
+ private:
   void SampleObject(Address soon_object, size_t size);
 
+  const std::vector<v8::AllocationProfile::Sample> BuildSamples() const;
+
+  AllocationNode* FindOrAddChildNode(AllocationNode* parent, const char* name,
+                                     int script_id, int start_position);
   static void OnWeakCallback(const WeakCallbackInfo<Sample>& data);
 
+  uint32_t next_node_id() { return ++last_node_id_; }
+  uint64_t next_sample_id() { return ++last_sample_id_; }
+
   // Methods that construct v8::AllocationProfile.
 
   // Translates the provided AllocationNode *node* returning an equivalent
@@ -131,11 +150,13 @@ class SamplingHeapProfiler {
       AllocationProfile* profile, SamplingHeapProfiler::AllocationNode* node,
       const std::map<int, Handle<Script>>& scripts);
   v8::AllocationProfile::Allocation ScaleSample(size_t size,
-                                                unsigned int count);
+                                                unsigned int count) const;
   AllocationNode* AddStack();
 
   Isolate* const isolate_;
   Heap* const heap_;
+  uint64_t last_sample_id_ = 0;
+  uint32_t last_node_id_ = 0;
   std::unique_ptr<SamplingAllocationObserver> new_space_observer_;
   std::unique_ptr<SamplingAllocationObserver> other_spaces_observer_;
   StringsStorage* const names_;
diff --git a/deps/v8/src/profiler/strings-storage.cc b/deps/v8/src/profiler/strings-storage.cc
index 9a5a006ff4..04a2379707 100644
--- a/deps/v8/src/profiler/strings-storage.cc
+++ b/deps/v8/src/profiler/strings-storage.cc
@@ -69,9 +69,9 @@ const char* StringsStorage::GetVFormatted(const char* format, va_list args) {
   return AddOrDisposeString(str.start(), len);
 }
 
-const char* StringsStorage::GetName(Name* name) {
+const char* StringsStorage::GetName(Name name) {
   if (name->IsString()) {
-    String* str = String::cast(name);
+    String str = String::cast(name);
     int length = Min(FLAG_heap_snapshot_string_limit, str->length());
     int actual_length = 0;
     std::unique_ptr<char[]> data = str->ToCString(
@@ -87,9 +87,9 @@ const char* StringsStorage::GetName(int index) {
   return GetFormatted("%d", index);
 }
 
-const char* StringsStorage::GetConsName(const char* prefix, Name* name) {
+const char* StringsStorage::GetConsName(const char* prefix, Name name) {
   if (name->IsString()) {
-    String* str = String::cast(name);
+    String str = String::cast(name);
     int length = Min(FLAG_heap_snapshot_string_limit, str->length());
     int actual_length = 0;
     std::unique_ptr<char[]> data = str->ToCString(
diff --git a/deps/v8/src/profiler/strings-storage.h b/deps/v8/src/profiler/strings-storage.h
index 5c0f8afd93..9b56a6e412 100644
--- a/deps/v8/src/profiler/strings-storage.h
+++ b/deps/v8/src/profiler/strings-storage.h
@@ -29,12 +29,12 @@ class V8_EXPORT_PRIVATE StringsStorage {
   // Returns a formatted string, de-duplicated via the storage.
   PRINTF_FORMAT(2, 3) const char* GetFormatted(const char* format, ...);
   // Returns a stored string resulting from name, or "<symbol>" for a symbol.
-  const char* GetName(Name* name);
+  const char* GetName(Name name);
   // Returns the string representation of the int from the store.
   const char* GetName(int index);
   // Appends string resulting from name to prefix, then returns the stored
   // result.
-  const char* GetConsName(const char* prefix, Name* name);
+  const char* GetConsName(const char* prefix, Name name);
 
  private:
   static bool StringsMatch(void* key1, void* key2);
diff --git a/deps/v8/src/profiler/tick-sample.cc b/deps/v8/src/profiler/tick-sample.cc
index 69a6bbf778..501dbd63a8 100644
--- a/deps/v8/src/profiler/tick-sample.cc
+++ b/deps/v8/src/profiler/tick-sample.cc
@@ -255,17 +255,16 @@ bool TickSample::GetStackSample(Isolate* v8_isolate, RegisterState* regs,
       // bytecode_array might be garbage, so don't actually dereference it. We
       // avoid the frame->GetXXX functions since they call BytecodeArray::cast,
       // which has a heap access in its DCHECK.
-      i::Object* bytecode_array = i::Memory<i::Object*>(
+      i::Address bytecode_array = i::Memory<i::Address>(
           frame->fp() + i::InterpreterFrameConstants::kBytecodeArrayFromFp);
-      i::Object* bytecode_offset = i::Memory<i::Object*>(
+      i::Address bytecode_offset = i::Memory<i::Address>(
           frame->fp() + i::InterpreterFrameConstants::kBytecodeOffsetFromFp);
 
       // If the bytecode array is a heap object and the bytecode offset is a
       // Smi, use those, otherwise fall back to using the frame's pc.
       if (HAS_HEAP_OBJECT_TAG(bytecode_array) && HAS_SMI_TAG(bytecode_offset)) {
         frames[i++] = reinterpret_cast<void*>(
-            reinterpret_cast<i::Address>(bytecode_array) +
-            i::Internals::SmiValue(bytecode_offset));
+            bytecode_array + i::Internals::SmiValue(bytecode_offset));
         continue;
       }
     }
@@ -287,5 +286,20 @@ void TickSample::Init(Isolate* isolate, const v8::RegisterState& state,
   timestamp = base::TimeTicks::HighResolutionNow();
 }
 
+void TickSample::print() const {
+  PrintF("TickSample: at %p\n", this);
+  PrintF(" - state: %s\n", StateToString(state));
+  PrintF(" - pc: %p\n", pc);
+  PrintF(" - stack: (%u frames)\n", frames_count);
+  for (unsigned i = 0; i < frames_count; i++) {
+    PrintF("    %p\n", stack[i]);
+  }
+  PrintF(" - has_external_callback: %d\n", has_external_callback);
+  PrintF(" - %s: %p\n",
+         has_external_callback ? "external_callback_entry" : "tos", tos);
+  PrintF(" - update_stats: %d\n", update_stats);
+  PrintF("\n");
+}
+
 }  // namespace internal
 }  // namespace v8
diff --git a/deps/v8/src/profiler/tick-sample.h b/deps/v8/src/profiler/tick-sample.h
index 819b862388..ea66010632 100644
--- a/deps/v8/src/profiler/tick-sample.h
+++ b/deps/v8/src/profiler/tick-sample.h
@@ -19,6 +19,8 @@ struct TickSample : public v8::TickSample {
             RecordCEntryFrame record_c_entry_frame, bool update_stats,
             bool use_simulator_reg_state = true);
   base::TimeTicks timestamp;
+
+  void print() const;
 };
 
 }  // namespace internal
diff --git a/deps/v8/src/profiler/tracing-cpu-profiler.cc b/deps/v8/src/profiler/tracing-cpu-profiler.cc
index 875478139d..0cb502bdf1 100644
--- a/deps/v8/src/profiler/tracing-cpu-profiler.cc
+++ b/deps/v8/src/profiler/tracing-cpu-profiler.cc
@@ -13,10 +13,6 @@ namespace internal {
 
 TracingCpuProfilerImpl::TracingCpuProfilerImpl(Isolate* isolate)
     : isolate_(isolate), profiling_enabled_(false) {
-  // Make sure tracing system notices profiler categories.
-  TRACE_EVENT_WARMUP_CATEGORY(TRACE_DISABLED_BY_DEFAULT("v8.cpu_profiler"));
-  TRACE_EVENT_WARMUP_CATEGORY(
-      TRACE_DISABLED_BY_DEFAULT("v8.cpu_profiler.hires"));
   V8::GetCurrentPlatform()->GetTracingController()->AddTraceStateObserver(this);
 }
 
@@ -40,7 +36,7 @@ void TracingCpuProfilerImpl::OnTraceEnabled() {
 }
 
 void TracingCpuProfilerImpl::OnTraceDisabled() {
-  base::LockGuard<base::Mutex> lock(&mutex_);
+  base::MutexGuard lock(&mutex_);
   if (!profiling_enabled_) return;
   profiling_enabled_ = false;
   isolate_->RequestInterrupt(
@@ -51,7 +47,7 @@ void TracingCpuProfilerImpl::OnTraceDisabled() {
 }
 
 void TracingCpuProfilerImpl::StartProfiling() {
-  base::LockGuard<base::Mutex> lock(&mutex_);
+  base::MutexGuard lock(&mutex_);
   if (!profiling_enabled_ || profiler_) return;
   bool enabled;
   TRACE_EVENT_CATEGORY_GROUP_ENABLED(
@@ -64,7 +60,7 @@ void TracingCpuProfilerImpl::StartProfiling() {
 }
 
 void TracingCpuProfilerImpl::StopProfiling() {
-  base::LockGuard<base::Mutex> lock(&mutex_);
+  base::MutexGuard lock(&mutex_);
   if (!profiler_) return;
   profiler_->StopProfiling("");
   profiler_.reset();