Reclaim the CreatedFromSnapshot bit and use it to indicate VM Heap object

runtime/vm/object.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 381 matching lines @@
 
   Heap* heap = isolate->heap();
 
   // Allocate and initialize the null instance.
   // 'null_' must be the first object allocated as it is used in allocation to
   // clear the object.
   {
     uword address = heap->Allocate(Instance::InstanceSize(), Heap::kOld);
     null_ = reinterpret_cast<RawInstance*>(address + kHeapObjectTag);
     // The call below is using 'null_' to initialize itself.
-    InitializeObject(address, kNullCid, Instance::InstanceSize());
+    InitializeObject(address, kNullCid, Instance::InstanceSize(), true);
   }
 }
 
 
 void Object::InitOnce(Isolate* isolate) {
   // Should only be run by the vm isolate.
   ASSERT(isolate == Dart::vm_isolate());
 
   // Initialize the static vtable values.
   {
@@ skipping 42 matching lines @@
   *empty_array_ = Array::null();
   *zero_array_ = Array::null();
 
   Class& cls = Class::Handle();
 
   // Allocate and initialize the class class.
   {
     intptr_t size = Class::InstanceSize();
     uword address = heap->Allocate(size, Heap::kOld);
     class_class_ = reinterpret_cast<RawClass*>(address + kHeapObjectTag);
-    InitializeObject(address, Class::kClassId, size);
+    InitializeObject(address, Class::kClassId, size, true);
 
     Class fake;
     // Initialization from Class::New<Class>.
     // Directly set raw_ to break a circular dependency: SetRaw will attempt
     // to lookup class class in the class table where it is not registered yet.
     cls.raw_ = class_class_;
     cls.set_handle_vtable(fake.vtable());
     cls.set_instance_size(Class::InstanceSize());
     cls.set_next_field_offset(Class::NextFieldOffset());
     cls.set_id(Class::kClassId);
@@ skipping 152 matching lines @@
   // need it when reading in the token stream of bootstrap classes in the VM
   // isolate.
   Class::NewExternalTypedDataClass(kExternalTypedDataUint8ArrayCid);
 
   // Needed for object pools of VM isolate stubs.
   Class::NewTypedDataClass(kTypedDataInt8ArrayCid);
 
   // Allocate and initialize the empty_array instance.
   {
     uword address = heap->Allocate(Array::InstanceSize(0), Heap::kOld);
-    InitializeObject(address, kImmutableArrayCid, Array::InstanceSize(0));
+    InitializeObject(address, kImmutableArrayCid, Array::InstanceSize(0), true);
     Array::initializeHandle(
         empty_array_,
         reinterpret_cast<RawArray*>(address + kHeapObjectTag));
     empty_array_->StoreSmi(&empty_array_->raw_ptr()->length_, Smi::New(0));
   }
 
   Smi& smi = Smi::Handle();
   // Allocate and initialize the zero_array instance.
   {
     uword address = heap->Allocate(Array::InstanceSize(1), Heap::kOld);
-    InitializeObject(address, kImmutableArrayCid, Array::InstanceSize(1));
+    InitializeObject(address, kImmutableArrayCid, Array::InstanceSize(1), true);
     Array::initializeHandle(
         zero_array_,
         reinterpret_cast<RawArray*>(address + kHeapObjectTag));
     zero_array_->StoreSmi(&zero_array_->raw_ptr()->length_, Smi::New(1));
     smi = Smi::New(0);
     zero_array_->SetAt(0, smi);
   }
 
   // Allocate and initialize the canonical empty object pool object.
   {
     uword address =
         heap->Allocate(ObjectPool::InstanceSize(0), Heap::kOld);
     InitializeObject(address,
                      kObjectPoolCid,
-                     ObjectPool::InstanceSize(0));
+                     ObjectPool::InstanceSize(0),
+                     true);
     ObjectPool::initializeHandle(
         empty_object_pool_,
         reinterpret_cast<RawObjectPool*>(address + kHeapObjectTag));
     empty_object_pool_->StoreNonPointer(
         &empty_object_pool_->raw_ptr()->length_, 0);
   }
 
   // Allocate and initialize the empty_descriptors instance.
   {
     uword address = heap->Allocate(PcDescriptors::InstanceSize(0), Heap::kOld);
     InitializeObject(address, kPcDescriptorsCid,
-                     PcDescriptors::InstanceSize(0));
+                     PcDescriptors::InstanceSize(0),
+                     true);
     PcDescriptors::initializeHandle(
         empty_descriptors_,
         reinterpret_cast<RawPcDescriptors*>(address + kHeapObjectTag));
     empty_descriptors_->StoreNonPointer(&empty_descriptors_->raw_ptr()->length_,
                                         0);
   }
 
   // Allocate and initialize the canonical empty variable descriptor object.
   {
     uword address =
         heap->Allocate(LocalVarDescriptors::InstanceSize(0), Heap::kOld);
     InitializeObject(address,
                      kLocalVarDescriptorsCid,
-                     LocalVarDescriptors::InstanceSize(0));
+                     LocalVarDescriptors::InstanceSize(0),
+                     true);
     LocalVarDescriptors::initializeHandle(
         empty_var_descriptors_,
         reinterpret_cast<RawLocalVarDescriptors*>(address + kHeapObjectTag));
     empty_var_descriptors_->StoreNonPointer(
         &empty_var_descriptors_->raw_ptr()->num_entries_, 0);
   }
 
   // Allocate and initialize the canonical empty exception handler info object.
   // The vast majority of all functions do not contain an exception handler
   // and can share this canonical descriptor.
   {
     uword address =
         heap->Allocate(ExceptionHandlers::InstanceSize(0), Heap::kOld);
     InitializeObject(address,
                      kExceptionHandlersCid,
-                     ExceptionHandlers::InstanceSize(0));
+                     ExceptionHandlers::InstanceSize(0),
+                     true);
     ExceptionHandlers::initializeHandle(
         empty_exception_handlers_,
         reinterpret_cast<RawExceptionHandlers*>(address + kHeapObjectTag));
     empty_exception_handlers_->StoreNonPointer(
         &empty_exception_handlers_->raw_ptr()->num_entries_, 0);
   }
 
   // The VM isolate snapshot object table is initialized to an empty array
   // as we do not have any VM isolate snapshot at this time.
   *vm_isolate_snapshot_object_table_ = Object::empty_array().raw();
@@ skipping 85 matching lines @@
 // An object visitor which will mark all visited objects. This is used to
 // premark all objects in the vm_isolate_ heap.
 class PremarkingVisitor : public ObjectVisitor {
  public:
   explicit PremarkingVisitor(Isolate* isolate) : ObjectVisitor(isolate) {}
 
   void VisitObject(RawObject* obj) {
     ASSERT(!obj->IsMarked());
     // Free list elements should never be marked.
     if (!obj->IsFreeListElement()) {
+      ASSERT(obj->IsVMHeapObject());
       obj->SetMarkBitUnsynchronized();
     }
   }
 };
 
 
 #define SET_CLASS_NAME(class_name, name)                                       \
   cls = class_name##_class();                                                  \
   cls.set_name(Symbols::name());                                               \
 
@@ skipping 845 matching lines @@
     return;
   }
 }
 
 
 RawString* Object::DictionaryName() const {
   return String::null();
 }
 
 
-void Object::InitializeObject(uword address, intptr_t class_id, intptr_t size) {
+void Object::InitializeObject(uword address,
+                              intptr_t class_id,
+                              intptr_t size,
+                              bool is_vm_object) {
   // TODO(iposva): Get a proper halt instruction from the assembler which
   // would be needed here for code objects.
   uword initial_value = reinterpret_cast<uword>(null_);
   uword cur = address;
   uword end = address + size;
   while (cur < end) {
     *reinterpret_cast<uword*>(cur) = initial_value;
     cur += kWordSize;
   }
   uword tags = 0;
   ASSERT(class_id != kIllegalCid);
   tags = RawObject::ClassIdTag::update(class_id, tags);
   tags = RawObject::SizeTag::update(size, tags);
+  tags = RawObject::VMHeapObjectTag::update(is_vm_object, tags);
   reinterpret_cast<RawObject*>(address)->tags_ = tags;
+  ASSERT(is_vm_object == RawObject::IsVMHeapObject(tags));
   VerifiedMemory::Accept(address, size);
 }
 
 
 void Object::CheckHandle() const {
 #if defined(DEBUG)
   if (raw_ != Object::null()) {
     if ((reinterpret_cast<uword>(raw_) & kSmiTagMask) == kSmiTag) {
       ASSERT(vtable() == Smi::handle_vtable_);
       return;
@@ skipping 37 matching lines @@
   if (space == Heap::kNew) {
     class_table->UpdateAllocatedNew(cls_id, size);
   } else {
     class_table->UpdateAllocatedOld(cls_id, size);
   }
   const Class& cls = Class::Handle(class_table->At(cls_id));
   if (cls.trace_allocation()) {
     Profiler::RecordAllocation(isolate, cls_id);
   }
   NoSafepointScope no_safepoint;
-  InitializeObject(address, cls_id, size);
+  InitializeObject(address, cls_id, size, (isolate == Dart::vm_isolate()));
   RawObject* raw_obj = reinterpret_cast<RawObject*>(address + kHeapObjectTag);
   ASSERT(cls_id == RawObject::ClassIdTag::decode(raw_obj->ptr()->tags_));
   return raw_obj;
 }
 
 
 class StoreBufferUpdateVisitor : public ObjectPointerVisitor {
  public:
   explicit StoreBufferUpdateVisitor(Thread* thread, RawObject* obj) :
       ObjectPointerVisitor(thread->isolate()), thread_(thread), old_obj_(obj) {
@@ skipping 73 matching lines @@
   return GeneratePrettyName();
 }
 
 
 RawString* Class::UserVisibleName() const {
   ASSERT(raw_ptr()->user_name_ != String::null());
   return raw_ptr()->user_name_;
 }
 
 
+bool Class::IsInFullSnapshot() const {
+  NoSafepointScope no_safepoint;
+  return raw_ptr()->library_->ptr()->is_in_fullsnapshot_;
+}
+
+
 RawType* Class::SignatureType() const {
   ASSERT(IsSignatureClass());
   const Function& function = Function::Handle(signature_function());
   ASSERT(!function.IsNull());
   if (function.signature_class() != raw()) {
     // This class is a function type alias. Return the canonical signature type.
     const Class& canonical_class = Class::Handle(function.signature_class());
     return canonical_class.SignatureType();
   }
   // Return the first canonical signature type if already computed at class
@@ skipping 7966 matching lines @@
                       GrowableObjectArray::New(4, Heap::kOld));
   result.StorePointer(&result.raw_ptr()->anonymous_classes_,
                       Object::empty_array().raw());
   result.StoreNonPointer(&result.raw_ptr()->num_anonymous_, 0);
   result.StorePointer(&result.raw_ptr()->imports_, Object::empty_array().raw());
   result.StorePointer(&result.raw_ptr()->exports_, Object::empty_array().raw());
   result.StorePointer(&result.raw_ptr()->loaded_scripts_, Array::null());
   result.StorePointer(&result.raw_ptr()->load_error_, Instance::null());
   result.set_native_entry_resolver(NULL);
   result.set_native_entry_symbol_resolver(NULL);
+  result.set_is_in_fullsnapshot(false);
   result.StoreNonPointer(&result.raw_ptr()->corelib_imported_, true);
   result.set_debuggable(false);
   result.set_is_dart_scheme(url.StartsWith(Symbols::DartScheme()));
   result.StoreNonPointer(&result.raw_ptr()->load_state_,
                          RawLibrary::kAllocated);
   result.StoreNonPointer(&result.raw_ptr()->index_, -1);
   const intptr_t kInitialNameCacheSize = 64;
   result.InitResolvedNamesCache(kInitialNameCacheSize);
   result.InitClassDictionary();
   result.InitImportList();
@@ skipping 5412 matching lines @@
     type ^= type.Canonicalize();
   }
   ASSERT(type.IsFinalized());
   return type.raw();
 }
 
 
 void Type::SetIsFinalized() const {
   ASSERT(!IsFinalized());
   if (IsInstantiated()) {
+    ASSERT(HasResolvedTypeClass());
     set_type_state(RawType::kFinalizedInstantiated);
   } else {
     set_type_state(RawType::kFinalizedUninstantiated);
   }
 }
 
 
 void Type::ResetIsFinalized() const {
   ASSERT(IsFinalized());
   set_type_state(RawType::kBeingFinalized);
@@ skipping 6072 matching lines @@
   return tag_label.ToCString();
 }
 
 
 void UserTag::PrintJSONImpl(JSONStream* stream, bool ref) const {
   Instance::PrintJSONImpl(stream, ref);
 }
 
 
 }  // namespace dart