arkcompiler_ets_runtime/ecmascript/ecma_handle_scope.h

/*
 * Copyright (c) 2021 Huawei Device Co., Ltd.
 * 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 ECMASCRIPT_HANDLE_SCOPE_H
#define ECMASCRIPT_HANDLE_SCOPE_H

#include "ecmascript/js_tagged_value.h"
#include "ecmascript/js_thread.h"
#ifdef ECMASCRIPT_ENABLE_HANDLE_LEAK_CHECK
#include "ecmascript/platform/backtrace.h"
#include "ecmascript/log_wrapper.h"
#include "ecmascript/mem/clock_scope.h"
#endif

namespace panda::ecmascript {
/*
 * Handles are only valid within a HandleScope. When a handle is created for an object a cell is allocated in the
 * current HandleScope.
 */
class EcmaHandleScope {
public:
    inline explicit EcmaHandleScope(JSThread *thread) :
        thread_(thread), prevNext_(thread->handleScopeStorageNext_), prevEnd_(thread->handleScopeStorageEnd_),
        prevHandleStorageIndex_(thread->currentHandleStorageIndex_)
    {
#ifdef ECMASCRIPT_ENABLE_HANDLE_LEAK_CHECK
        thread_->HandleScopeCountAdd();
        prevHandleScope_ = thread->GetLastHandleScope();
        thread_->SetLastHandleScope(this);
#endif
    }

    inline ~EcmaHandleScope()
    {
#ifdef ECMASCRIPT_ENABLE_HANDLE_LEAK_CHECK
        thread_->HandleScopeCountDec();
        thread_->SetLastHandleScope(prevHandleScope_);
        prevHandleScope_ = nullptr;
#endif
        thread_->handleScopeStorageNext_ = prevNext_;
        if (thread_->handleScopeStorageEnd_ != prevEnd_) {
            thread_->handleScopeStorageEnd_ = prevEnd_;
            thread_->ShrinkHandleStorage(prevHandleStorageIndex_);
        }
    }

    static inline uintptr_t PUBLIC_API NewHandle(JSThread *thread, JSTaggedType value)
    {
#ifdef ECMASCRIPT_ENABLE_HANDLE_LEAK_CHECK
        // Each Handle must be managed by HandleScope, otherwise it may cause Handle leakage.
        if (thread->handleScopeCount_ <= 0) {
            LOG_ECMA(ERROR) << "New handle must be in handlescope" << thread->handleScopeCount_;
        }
        static const long MAYBE_HANDLE_LEAK_TIME_MS = 5000;
        if (thread->GetLastHandleScope() != nullptr) {
            float totalSpentTime = thread->GetLastHandleScope()->scope_.TotalSpentTime();
            if (totalSpentTime >= MAYBE_HANDLE_LEAK_TIME_MS) {
                LOG_ECMA(INFO) << "New handle in scope count:" << thread->handleScopeCount_
                               << ", time:" << totalSpentTime << "ms";
                std::ostringstream stack;
                Backtrace(stack, true);
                LOG_ECMA(INFO) << stack.str();
            }
        }
#endif
#if ECMASCRIPT_ENABLE_NEW_HANDLE_CHECK
        thread->CheckJSTaggedType(value);
#endif
        auto result = thread->handleScopeStorageNext_;
        if (result == thread->handleScopeStorageEnd_) {
            result = reinterpret_cast<JSTaggedType *>(thread->ExpandHandleStorage());
        }
        // NOLINTNEXTLINE(cppcoreguidelines-pro-bounds-pointer-arithmetic)
        thread->handleScopeStorageNext_ = result + 1;
        *result = value;
        return reinterpret_cast<uintptr_t>(result);
    }

    JSThread *GetThread() const
    {
        return thread_;
    }

private:
    JSThread *thread_;
    JSTaggedType *prevNext_;
    JSTaggedType *prevEnd_;
    int prevHandleStorageIndex_ {-1};
#ifdef ECMASCRIPT_ENABLE_HANDLE_LEAK_CHECK
    ClockScope scope_;
    EcmaHandleScope *prevHandleScope_ {nullptr};
#endif

    NO_COPY_SEMANTIC(EcmaHandleScope);
    NO_MOVE_SEMANTIC(EcmaHandleScope);
};
}  // namespace panda::ecmascript
#endif  // ECMASCRIPT_HANDLE_SCOPE_H