Reapply "[vm] Streamline Zones."

Fix imprecision in Zone::SizeInBytes that was finally noticed by vm/cc/AllocateZone because the size of the initial inline buffer changed.

TEST=ci
Bug: #47399
Change-Id: I152d24d03a59b21267a9a24e5d929b51af57af71
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/215980
Reviewed-by: Siva Annamalai <[email protected]>
Commit-Queue: Ryan Macnak <[email protected]>

Author: rmacnak-google

runtime/vm/benchmark_test.cc

@@ -48,7 +48,6 @@ BENCHMARK(CorelibCompileAll) {
   bin::Builtin::SetNativeResolver(bin::Builtin::kCLILibrary);
   TransitionNativeToVM transition(thread);
   StackZone zone(thread);
-  HANDLESCOPE(thread);
   Timer timer;
   timer.Start();
   const Error& error =
@@ -413,7 +412,6 @@ BENCHMARK_SIZE(CoreSnapshotSize) {
 
   TransitionNativeToVM transition(thread);
   StackZone zone(thread);
-  HANDLESCOPE(thread);
 
   Api::CheckAndFinalizePendingClasses(thread);
 
@@ -451,7 +449,6 @@ BENCHMARK_SIZE(StandaloneSnapshotSize) {
 
   TransitionNativeToVM transition(thread);
   StackZone zone(thread);
-  HANDLESCOPE(thread);
 
   Api::CheckAndFinalizePendingClasses(thread);
 
@@ -496,7 +493,6 @@ BENCHMARK(EnterExitIsolate) {
   {
     TransitionNativeToVM transition(thread);
     StackZone zone(thread);
-    HANDLESCOPE(thread);
     Api::CheckAndFinalizePendingClasses(thread);
   }
   Dart_Isolate isolate = Dart_CurrentIsolate();
@@ -514,7 +510,6 @@ BENCHMARK(EnterExitIsolate) {
 BENCHMARK(SerializeNull) {
   TransitionNativeToVM transition(thread);
   StackZone zone(thread);
-  HANDLESCOPE(thread);
   const Object& null_object = Object::Handle();
   const intptr_t kLoopCount = 1000000;
   Timer timer;
@@ -536,7 +531,6 @@ BENCHMARK(SerializeNull) {
 BENCHMARK(SerializeSmi) {
   TransitionNativeToVM transition(thread);
   StackZone zone(thread);
-  HANDLESCOPE(thread);
   const Integer& smi_object = Integer::Handle(Smi::New(42));
   const intptr_t kLoopCount = 1000000;
   Timer timer;
@@ -558,7 +552,6 @@ BENCHMARK(SerializeSmi) {
 BENCHMARK(SimpleMessage) {
   TransitionNativeToVM transition(thread);
   StackZone zone(thread);
-  HANDLESCOPE(thread);
   const Array& array_object = Array::Handle(Array::New(2));
   array_object.SetAt(0, Integer::Handle(Smi::New(42)));
   array_object.SetAt(1, Object::Handle());
@@ -592,7 +585,6 @@ BENCHMARK(LargeMap) {
   EXPECT_VALID(h_result);
   TransitionNativeToVM transition(thread);
   StackZone zone(thread);
-  HANDLESCOPE(thread);
   Instance& map = Instance::Handle();
   map ^= Api::UnwrapHandle(h_result);
   const intptr_t kLoopCount = 100;

runtime/vm/class_finalizer.cc

@@ -1731,7 +1731,6 @@ void ClassFinalizer::ClearAllCode(bool including_nonchanging_cids) {
   auto const isolate_group = thread->isolate_group();
   SafepointWriteRwLocker ml(thread, isolate_group->program_lock());
   StackZone stack_zone(thread);
-  HANDLESCOPE(thread);
   auto const zone = thread->zone();
 
   class ClearCodeVisitor : public FunctionVisitor {

runtime/vm/compiler/aot/precompiler.cc

@@ -3028,7 +3028,6 @@ void Precompiler::FinalizeAllClasses() {
   // otherwise unreachable constants of dropped classes, which would
   // cause assertion failures during GC after classes are dropped.
   StackZone stack_zone(thread());
-  HANDLESCOPE(thread());
 
   error_ = Library::FinalizeAllClasses();
   if (!error_.IsNull()) {

runtime/vm/compiler/jit/compiler.cc

@@ -1133,7 +1133,6 @@ void BackgroundCompiler::Run() {
       Thread* thread = Thread::Current();
       StackZone stack_zone(thread);
       Zone* zone = stack_zone.GetZone();
-      HANDLESCOPE(thread);
       Function& function = Function::Handle(zone);
       {
         SafepointMonitorLocker ml(&queue_monitor_);

runtime/vm/compiler/runtime_offsets_extracted.h

@@ -1301,7 +1301,6 @@ static Dart_Isolate CreateIsolate(IsolateGroup* group,
   bool success = false;
   {
     StackZone zone(T);
-    HANDLESCOPE(T);
     // We enter an API scope here as InitializeIsolate could compile some
     // bootstrap library files which call out to a tag handler that may create
     // Api Handles when an error is encountered.
@@ -2053,7 +2052,6 @@ DART_EXPORT bool Dart_RunLoopAsync(bool errors_are_fatal,
     auto thread = Thread::Current();
     TransitionNativeToVM transition(thread);
     StackZone zone(thread);
-    HANDLESCOPE(thread);
 
     if (on_error_port != ILLEGAL_PORT) {
       const auto& port =

runtime/vm/dart_api_impl.cc

@@ -3128,7 +3128,6 @@ VM_UNIT_TEST_CASE(DartAPI_PersistentHandles) {
   {
     TransitionNativeToVM transition(thread);
     StackZone zone(thread);
-    HANDLESCOPE(thread);
     for (int i = 0; i < 500; i++) {
       String& str = String::Handle();
       str ^= PersistentHandle::Cast(handles[i])->ptr();
@@ -4551,7 +4550,6 @@ VM_UNIT_TEST_CASE(DartAPI_LocalHandles) {
   {
     TransitionNativeToVM transition1(thread);
     StackZone zone(thread);
-    HANDLESCOPE(thread);
     Smi& val = Smi::Handle();
     TransitionVMToNative transition2(thread);
 
@@ -4619,9 +4617,11 @@ VM_UNIT_TEST_CASE(DartAPI_LocalZoneMemory) {
   Thread* thread = Thread::Current();
   EXPECT(thread != NULL);
   ApiLocalScope* scope = thread->api_top_scope();
+  EXPECT_EQ(0, thread->ZoneSizeInBytes());
   {
     // Start a new scope and allocate some memory.
     Dart_EnterScope();
+    EXPECT_EQ(0, thread->ZoneSizeInBytes());
     for (int i = 0; i < 100; i++) {
       Dart_ScopeAllocate(16);
     }

runtime/vm/dart_api_impl_test.cc

@@ -14,6 +14,4 @@
 
 namespace dart {
 
-RelaxedAtomic<intptr_t> ApiNativeScope::current_memory_usage_ = 0;
-
 }  // namespace dart

runtime/vm/dart_api_state.cc

@@ -110,7 +110,7 @@ class ApiZone {
     if ((thread != NULL) && (thread->zone() == &zone_)) {
       thread->set_zone(zone_.previous_);
     }
-    zone_.DeleteAll();
+    zone_.Reset();
   }
 
  private:
@@ -656,35 +656,18 @@ class ApiNativeScope {
     ASSERT(Current() == NULL);
     OSThread::SetThreadLocal(Api::api_native_key_,
                              reinterpret_cast<uword>(this));
-    // We manually increment the memory usage counter since there is memory
-    // initially allocated within the zone on creation.
-    IncrementNativeScopeMemoryCapacity(zone_.GetZone()->CapacityInBytes());
   }
 
   ~ApiNativeScope() {
     ASSERT(Current() == this);
     OSThread::SetThreadLocal(Api::api_native_key_, 0);
-    // We must also manually decrement the memory usage counter since the native
-    // is still holding it's initial memory and ~Zone() won't be able to
-    // determine which memory usage counter to decrement.
-    DecrementNativeScopeMemoryCapacity(zone_.GetZone()->CapacityInBytes());
   }
 
   static inline ApiNativeScope* Current() {
     return reinterpret_cast<ApiNativeScope*>(
         OSThread::GetThreadLocal(Api::api_native_key_));
   }
 
-  static uintptr_t current_memory_usage() { return current_memory_usage_; }
-
-  static void IncrementNativeScopeMemoryCapacity(intptr_t size) {
-    current_memory_usage_.fetch_add(size);
-  }
-
-  static void DecrementNativeScopeMemoryCapacity(intptr_t size) {
-    current_memory_usage_.fetch_sub(size);
-  }
-
   Zone* zone() {
     Zone* result = zone_.GetZone();
     ASSERT(result->handles()->CountScopedHandles() == 0);
@@ -693,9 +676,6 @@ class ApiNativeScope {
   }
 
  private:
-  // The current total memory usage within ApiNativeScopes.
-  static RelaxedAtomic<intptr_t> current_memory_usage_;
-
   ApiZone zone_;
 };
 

runtime/vm/dart_api_state.h

@@ -19,16 +19,6 @@ namespace dart {
 
 DEFINE_FLAG(bool, verify_handles, false, "Verify handles.");
 
-VMHandles::~VMHandles() {
-  if (FLAG_trace_handles) {
-    OS::PrintErr("***   Handle Counts for 0x(%" Px "):Zone = %d,Scoped = %d\n",
-                 reinterpret_cast<intptr_t>(this), CountZoneHandles(),
-                 CountScopedHandles());
-    OS::PrintErr("*** Deleting VM handle block 0x%" Px "\n",
-                 reinterpret_cast<intptr_t>(this));
-  }
-}
-
 void VMHandles::VisitObjectPointers(ObjectPointerVisitor* visitor) {
   return Handles<kVMHandleSizeInWords, kVMHandlesPerChunk,
                  kOffsetOfRawPtr>::VisitObjectPointers(visitor);

runtime/vm/handles.cc

@@ -107,6 +107,24 @@ class Handles {
     return true;
   }
 
+  intptr_t ZoneHandlesCapacityInBytes() const {
+    intptr_t capacity = 0;
+    for (HandlesBlock* block = zone_blocks_; block != nullptr;
+         block = block->next_block()) {
+      capacity += sizeof(*block);
+    }
+    return capacity;
+  }
+
+  intptr_t ScopedHandlesCapacityInBytes() const {
+    intptr_t capacity = 0;
+    for (HandlesBlock* block = scoped_blocks_; block != nullptr;
+         block = block->next_block()) {
+      capacity += sizeof(*block);
+    }
+    return capacity;
+  }
+
  protected:
   // Returns a count of active handles (used for testing purposes).
   int CountScopedHandles() const;
@@ -126,7 +144,7 @@ class Handles {
   class HandlesBlock : public MallocAllocated {
    public:
     explicit HandlesBlock(HandlesBlock* next)
-        : next_handle_slot_(0), next_block_(next) {}
+        : next_block_(next), next_handle_slot_(0) {}
     ~HandlesBlock();
 
     // Reinitializes handle block for reuse.
@@ -175,9 +193,9 @@ class Handles {
     void set_next_block(HandlesBlock* next) { next_block_ = next; }
 
    private:
-    uword data_[kHandleSizeInWords * kHandlesPerChunk];  // Handles area.
-    intptr_t next_handle_slot_;  // Next slot for allocation in current block.
     HandlesBlock* next_block_;   // Link to next block of handles.
+    intptr_t next_handle_slot_;  // Next slot for allocation in current block.
+    uword data_[kHandleSizeInWords * kHandlesPerChunk];  // Handles area.
 
     DISALLOW_COPY_AND_ASSIGN(HandlesBlock);
   };
@@ -222,7 +240,7 @@ class Handles {
 };
 
 static const int kVMHandleSizeInWords = 2;
-static const int kVMHandlesPerChunk = 64;
+static const int kVMHandlesPerChunk = 63;
 static const int kOffsetOfRawPtr = kWordSize;
 class VMHandles : public Handles<kVMHandleSizeInWords,
                                  kVMHandlesPerChunk,
@@ -232,12 +250,25 @@ class VMHandles : public Handles<kVMHandleSizeInWords,
 
   VMHandles()
       : Handles<kVMHandleSizeInWords, kVMHandlesPerChunk, kOffsetOfRawPtr>() {
+#if defined(DEBUG)
     if (FLAG_trace_handles) {
       OS::PrintErr("*** Starting a new VM handle block 0x%" Px "\n",
                    reinterpret_cast<intptr_t>(this));
     }
+#endif
+  }
+  ~VMHandles() {
+#if defined(DEBUG)
+    if (FLAG_trace_handles) {
+      OS::PrintErr("***   Handle Counts for 0x(%" Px
+                   "):Zone = %d,Scoped = %d\n",
+                   reinterpret_cast<intptr_t>(this), CountZoneHandles(),
+                   CountScopedHandles());
+      OS::PrintErr("*** Deleting VM handle block 0x%" Px "\n",
+                   reinterpret_cast<intptr_t>(this));
+    }
+#endif
   }
-  ~VMHandles();
 
   // Visit all object pointers stored in the various handles.
   void VisitObjectPointers(ObjectPointerVisitor* visitor);

runtime/vm/handles.h

@@ -81,7 +81,6 @@ uword Handles<kHandleSizeInWords, kHandlesPerChunk, kOffsetOfRawPtr>::
     AllocateHandle(Zone* zone) {
 #if defined(DEBUG)
   Thread* thread = Thread::Current();
-  ASSERT(thread->top_handle_scope() != NULL);
   ASSERT(thread->MayAllocateHandles());
 #endif  // DEBUG
   Handles* handles = zone->handles();

runtime/vm/handles_impl.h

@@ -592,7 +592,6 @@ VM_UNIT_TEST_CASE(CleanupBequestNeverReceived) {
       Thread* thread = Thread::Current();
       TransitionNativeToVM transition(thread);
       StackZone zone(thread);
-      HANDLESCOPE(thread);
 
       String& string = String::Handle(String::New(TEST_MESSAGE));
       PersistentHandle* handle =
@@ -626,7 +625,6 @@ VM_UNIT_TEST_CASE(ReceivesSendAndExitMessage) {
     Thread* thread = Thread::Current();
     TransitionNativeToVM transition(thread);
     StackZone zone(thread);
-    HANDLESCOPE(thread);
 
     String& string = String::Handle(String::New(TEST_MESSAGE));
 
@@ -644,7 +642,6 @@ VM_UNIT_TEST_CASE(ReceivesSendAndExitMessage) {
     Thread* thread = Thread::Current();
     TransitionNativeToVM transition(thread);
     StackZone zone(thread);
-    HANDLESCOPE(thread);
 
     EXPECT_EQ(MessageHandler::kOK, handler.HandleNextMessage());
   }

runtime/vm/heap/heap_test.cc

@@ -174,7 +174,6 @@ class RunKernelTask : public ThreadPool::Task {
     Thread* T = Thread::Current();
     ASSERT(I == T->isolate());
     StackZone zone(T);
-    HANDLESCOPE(T);
     // Invoke main which will return the port to which load requests are sent.
     const Library& root_library =
         Library::Handle(Z, I->group()->object_store()->root_library());

runtime/vm/kernel_isolate.cc

@@ -53,7 +53,6 @@ VM_UNIT_TEST_CASE(Metric_OnDemand) {
     Thread* thread = Thread::Current();
     TransitionNativeToVM transition(thread);
     StackZone zone(thread);
-    HANDLESCOPE(thread);
     MyMetric metric;
 
     metric.InitInstance(Isolate::Current(), "a.b.c", "foobar", Metric::kByte);

runtime/vm/metrics_test.cc

@@ -1777,7 +1777,6 @@ void ProfilerService::PrintJSONImpl(Thread* thread,
   ASSERT(buffer != nullptr);
 
   StackZone zone(thread);
-  HANDLESCOPE(thread);
   Profile profile;
   profile.Build(thread, filter, buffer);
   profile.PrintProfileJSON(stream, include_code_samples);