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/*
* Copyright (C) 2015 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.
*/
#ifndef ART_RUNTIME_CLASS_TABLE_INL_H_
#define ART_RUNTIME_CLASS_TABLE_INL_H_
#include "class_table.h"
#include "base/mutex-inl.h"
#include "dex/utf.h"
#include "gc_root-inl.h"
#include "mirror/class.h"
#include "oat_file.h"
#include "obj_ptr-inl.h"
namespace art {
inline uint32_t ClassTable::ClassDescriptorHash::operator()(const TableSlot& slot) const {
std::string temp;
// No read barrier needed, we're reading a chain of constant references for comparison
// with null and retrieval of constant primitive data. See ReadBarrierOption.
return ComputeModifiedUtf8Hash(slot.Read<kWithoutReadBarrier>()->GetDescriptor(&temp));
}
inline uint32_t ClassTable::ClassDescriptorHash::operator()(const DescriptorHashPair& pair) const {
DCHECK_EQ(ComputeModifiedUtf8Hash(pair.first), pair.second);
return pair.second;
}
inline bool ClassTable::ClassDescriptorEquals::operator()(const TableSlot& a,
const TableSlot& b) const {
// No read barrier needed, we're reading a chain of constant references for comparison
// with null and retrieval of constant primitive data. See ReadBarrierOption.
if (a.Hash() != b.Hash()) {
std::string temp;
DCHECK(!a.Read<kWithoutReadBarrier>()->DescriptorEquals(
b.Read<kWithoutReadBarrier>()->GetDescriptor(&temp)));
return false;
}
std::string temp;
return a.Read<kWithoutReadBarrier>()->DescriptorEquals(
b.Read<kWithoutReadBarrier>()->GetDescriptor(&temp));
}
inline bool ClassTable::ClassDescriptorEquals::operator()(const TableSlot& a,
const DescriptorHashPair& b) const {
// No read barrier needed, we're reading a chain of constant references for comparison
// with null and retrieval of constant primitive data. See ReadBarrierOption.
if (!a.MaskedHashEquals(b.second)) {
DCHECK(!a.Read<kWithoutReadBarrier>()->DescriptorEquals(b.first));
return false;
}
return a.Read<kWithoutReadBarrier>()->DescriptorEquals(b.first);
}
template<class Visitor>
void ClassTable::VisitRoots(Visitor& visitor) {
ReaderMutexLock mu(Thread::Current(), lock_);
for (ClassSet& class_set : classes_) {
for (TableSlot& table_slot : class_set) {
table_slot.VisitRoot(visitor);
}
}
for (GcRoot<mirror::Object>& root : strong_roots_) {
visitor.VisitRoot(root.AddressWithoutBarrier());
}
for (const OatFile* oat_file : oat_files_) {
for (GcRoot<mirror::Object>& root : oat_file->GetBssGcRoots()) {
visitor.VisitRootIfNonNull(root.AddressWithoutBarrier());
}
}
}
template<class Visitor>
void ClassTable::VisitRoots(const Visitor& visitor) {
ReaderMutexLock mu(Thread::Current(), lock_);
for (ClassSet& class_set : classes_) {
for (TableSlot& table_slot : class_set) {
table_slot.VisitRoot(visitor);
}
}
for (GcRoot<mirror::Object>& root : strong_roots_) {
visitor.VisitRoot(root.AddressWithoutBarrier());
}
for (const OatFile* oat_file : oat_files_) {
for (GcRoot<mirror::Object>& root : oat_file->GetBssGcRoots()) {
visitor.VisitRootIfNonNull(root.AddressWithoutBarrier());
}
}
}
template <typename Visitor, ReadBarrierOption kReadBarrierOption>
bool ClassTable::Visit(Visitor& visitor) {
ReaderMutexLock mu(Thread::Current(), lock_);
for (ClassSet& class_set : classes_) {
for (TableSlot& table_slot : class_set) {
if (!visitor(table_slot.Read<kReadBarrierOption>())) {
return false;
}
}
}
return true;
}
template <typename Visitor, ReadBarrierOption kReadBarrierOption>
bool ClassTable::Visit(const Visitor& visitor) {
ReaderMutexLock mu(Thread::Current(), lock_);
for (ClassSet& class_set : classes_) {
for (TableSlot& table_slot : class_set) {
if (!visitor(table_slot.Read<kReadBarrierOption>())) {
return false;
}
}
}
return true;
}
inline bool ClassTable::TableSlot::IsNull() const {
return Read<kWithoutReadBarrier>() == nullptr;
}
template<ReadBarrierOption kReadBarrierOption>
inline ObjPtr<mirror::Class> ClassTable::TableSlot::Read() const {
const uint32_t before = data_.load(std::memory_order_relaxed);
const ObjPtr<mirror::Class> before_ptr(ExtractPtr(before));
const ObjPtr<mirror::Class> after_ptr(
GcRoot<mirror::Class>(before_ptr).Read<kReadBarrierOption>());
if (kReadBarrierOption != kWithoutReadBarrier && before_ptr != after_ptr) {
// If another thread raced and updated the reference, do not store the read barrier updated
// one.
data_.CompareAndSetStrongRelease(before, Encode(after_ptr, MaskHash(before)));
}
return after_ptr;
}
template<typename Visitor>
inline void ClassTable::TableSlot::VisitRoot(const Visitor& visitor) const {
const uint32_t before = data_.load(std::memory_order_relaxed);
ObjPtr<mirror::Class> before_ptr(ExtractPtr(before));
GcRoot<mirror::Class> root(before_ptr);
visitor.VisitRoot(root.AddressWithoutBarrier());
ObjPtr<mirror::Class> after_ptr(root.Read<kWithoutReadBarrier>());
if (before_ptr != after_ptr) {
// If another thread raced and updated the reference, do not store the read barrier updated
// one.
data_.CompareAndSetStrongRelease(before, Encode(after_ptr, MaskHash(before)));
}
}
inline ObjPtr<mirror::Class> ClassTable::TableSlot::ExtractPtr(uint32_t data) {
return reinterpret_cast<mirror::Class*>(data & ~kHashMask);
}
inline uint32_t ClassTable::TableSlot::Encode(ObjPtr<mirror::Class> klass, uint32_t hash_bits) {
DCHECK_LE(hash_bits, kHashMask);
return reinterpret_cast<uintptr_t>(klass.Ptr()) | hash_bits;
}
inline ClassTable::TableSlot::TableSlot(ObjPtr<mirror::Class> klass, uint32_t descriptor_hash)
: data_(Encode(klass, MaskHash(descriptor_hash))) {
DCHECK_EQ(descriptor_hash, HashDescriptor(klass));
}
template <typename Filter>
inline void ClassTable::RemoveStrongRoots(const Filter& filter) {
WriterMutexLock mu(Thread::Current(), lock_);
strong_roots_.erase(std::remove_if(strong_roots_.begin(), strong_roots_.end(), filter),
strong_roots_.end());
}
inline ObjPtr<mirror::Class> ClassTable::LookupByDescriptor(ObjPtr<mirror::Class> klass) {
std::string temp;
const char* descriptor = klass->GetDescriptor(&temp);
uint32_t hash = TableSlot::HashDescriptor(klass);
return Lookup(descriptor, hash);
}
} // namespace art
#endif // ART_RUNTIME_CLASS_TABLE_INL_H_
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