| /* |
| * Copyright (C) 2011 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include <ctime> |
| |
| #include "object.h" |
| |
| #include "art_field.h" |
| #include "art_field-inl.h" |
| #include "array-inl.h" |
| #include "class.h" |
| #include "class-inl.h" |
| #include "class_linker-inl.h" |
| #include "gc/accounting/card_table-inl.h" |
| #include "gc/heap.h" |
| #include "iftable-inl.h" |
| #include "monitor.h" |
| #include "object-inl.h" |
| #include "object_array-inl.h" |
| #include "object_utils.h" |
| #include "runtime.h" |
| #include "sirt_ref.h" |
| #include "throwable.h" |
| #include "well_known_classes.h" |
| |
| namespace art { |
| namespace mirror { |
| |
| Object* Object::Clone(Thread* self) { |
| Class* c = GetClass(); |
| DCHECK(!c->IsClassClass()); |
| |
| // Object::SizeOf gets the right size even if we're an array. |
| // Using c->AllocObject() here would be wrong. |
| size_t num_bytes = SizeOf(); |
| gc::Heap* heap = Runtime::Current()->GetHeap(); |
| SirtRef<Object> copy(self, heap->AllocObject(self, c, num_bytes)); |
| if (copy.get() == NULL) { |
| return NULL; |
| } |
| |
| // Copy instance data. We assume memcpy copies by words. |
| // TODO: expose and use move32. |
| byte* src_bytes = reinterpret_cast<byte*>(this); |
| byte* dst_bytes = reinterpret_cast<byte*>(copy.get()); |
| size_t offset = sizeof(Object); |
| memcpy(dst_bytes + offset, src_bytes + offset, num_bytes - offset); |
| |
| // Perform write barriers on copied object references. |
| if (c->IsArrayClass()) { |
| if (!c->GetComponentType()->IsPrimitive()) { |
| const ObjectArray<Object>* array = copy->AsObjectArray<Object>(); |
| heap->WriteBarrierArray(copy.get(), 0, array->GetLength()); |
| } |
| } else { |
| for (const Class* klass = c; klass != NULL; klass = klass->GetSuperClass()) { |
| size_t num_reference_fields = klass->NumReferenceInstanceFields(); |
| for (size_t i = 0; i < num_reference_fields; ++i) { |
| ArtField* field = klass->GetInstanceField(i); |
| MemberOffset field_offset = field->GetOffset(); |
| const Object* ref = copy->GetFieldObject<const Object*>(field_offset, false); |
| heap->WriteBarrierField(copy.get(), field_offset, ref); |
| } |
| } |
| } |
| |
| if (c->IsFinalizable()) { |
| heap->AddFinalizerReference(Thread::Current(), copy.get()); |
| } |
| |
| return copy.get(); |
| } |
| |
| int32_t Object::GenerateIdentityHashCode() { |
| static AtomicInteger seed(987654321 + std::time(nullptr)); |
| int32_t expected_value, new_value; |
| do { |
| expected_value = static_cast<uint32_t>(seed.load()); |
| new_value = expected_value * 1103515245 + 12345; |
| } while ((expected_value & LockWord::kHashMask) == 0 || |
| !seed.compare_and_swap(expected_value, new_value)); |
| return expected_value & LockWord::kHashMask; |
| } |
| |
| int32_t Object::IdentityHashCode() const { |
| while (true) { |
| LockWord lw = GetLockWord(); |
| switch (lw.GetState()) { |
| case LockWord::kUnlocked: { |
| // Try to compare and swap in a new hash, if we succeed we will return the hash on the next |
| // loop iteration. |
| LockWord hash_word(LockWord::FromHashCode(GenerateIdentityHashCode())); |
| DCHECK_EQ(hash_word.GetState(), LockWord::kHashCode); |
| if (const_cast<Object*>(this)->CasLockWord(lw, hash_word)) { |
| return hash_word.GetHashCode(); |
| } |
| break; |
| } |
| case LockWord::kThinLocked: { |
| // Inflate the thin lock to a monitor and stick the hash code inside of the monitor. |
| Thread* self = Thread::Current(); |
| Monitor::InflateThinLocked(self, const_cast<Object*>(this), lw, GenerateIdentityHashCode()); |
| break; |
| } |
| case LockWord::kFatLocked: { |
| // Already inflated, return the has stored in the monitor. |
| Monitor* monitor = lw.FatLockMonitor(); |
| DCHECK(monitor != nullptr); |
| return monitor->GetHashCode(); |
| } |
| case LockWord::kHashCode: { |
| return lw.GetHashCode(); |
| } |
| } |
| } |
| LOG(FATAL) << "Unreachable"; |
| return 0; |
| } |
| |
| void Object::CheckFieldAssignmentImpl(MemberOffset field_offset, const Object* new_value) { |
| const Class* c = GetClass(); |
| if (Runtime::Current()->GetClassLinker() == NULL || |
| !Runtime::Current()->GetHeap()->IsObjectValidationEnabled() || |
| !c->IsResolved()) { |
| return; |
| } |
| for (const Class* cur = c; cur != NULL; cur = cur->GetSuperClass()) { |
| ObjectArray<ArtField>* fields = cur->GetIFields(); |
| if (fields != NULL) { |
| size_t num_ref_ifields = cur->NumReferenceInstanceFields(); |
| for (size_t i = 0; i < num_ref_ifields; ++i) { |
| ArtField* field = fields->Get(i); |
| if (field->GetOffset().Int32Value() == field_offset.Int32Value()) { |
| FieldHelper fh(field); |
| CHECK(fh.GetType()->IsAssignableFrom(new_value->GetClass())); |
| return; |
| } |
| } |
| } |
| } |
| if (c->IsArrayClass()) { |
| // Bounds and assign-ability done in the array setter. |
| return; |
| } |
| if (IsClass()) { |
| ObjectArray<ArtField>* fields = AsClass()->GetSFields(); |
| if (fields != NULL) { |
| size_t num_ref_sfields = AsClass()->NumReferenceStaticFields(); |
| for (size_t i = 0; i < num_ref_sfields; ++i) { |
| ArtField* field = fields->Get(i); |
| if (field->GetOffset().Int32Value() == field_offset.Int32Value()) { |
| FieldHelper fh(field); |
| CHECK(fh.GetType()->IsAssignableFrom(new_value->GetClass())); |
| return; |
| } |
| } |
| } |
| } |
| LOG(FATAL) << "Failed to find field for assignment to " << reinterpret_cast<void*>(this) |
| << " of type " << PrettyDescriptor(c) << " at offset " << field_offset; |
| } |
| |
| } // namespace mirror |
| } // namespace art |