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// Copyright 2020 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_HEAP_BASE_SPACE_H_
#define V8_HEAP_BASE_SPACE_H_
#include <atomic>
#include "src/base/macros.h"
#include "src/common/globals.h"
#include "src/heap/heap-verifier.h"
#include "src/utils/allocation.h"
namespace v8 {
namespace internal {
class Heap;
// ----------------------------------------------------------------------------
// BaseSpace is the abstract superclass for all allocation spaces.
class V8_EXPORT_PRIVATE BaseSpace : public Malloced {
public:
BaseSpace(const BaseSpace&) = delete;
BaseSpace& operator=(const BaseSpace&) = delete;
Heap* heap() const {
DCHECK_NOT_NULL(heap_);
return heap_;
}
AllocationSpace identity() const { return id_; }
// Return the total amount committed memory for this space, i.e., allocatable
// memory and page headers.
virtual size_t CommittedMemory() const { return committed_; }
virtual size_t MaximumCommittedMemory() const { return max_committed_; }
// Approximate amount of physical memory committed for this space.
virtual size_t CommittedPhysicalMemory() const = 0;
// Returns allocated size.
virtual size_t Size() const = 0;
#ifdef VERIFY_HEAP
virtual void Verify(Isolate* isolate,
SpaceVerificationVisitor* visitor) const = 0;
#endif // VERIFY_HEAP
protected:
BaseSpace(Heap* heap, AllocationSpace id) : heap_(heap), id_(id) {}
virtual ~BaseSpace() = default;
void AccountCommitted(size_t bytes) {
DCHECK_GE(committed_ + bytes, committed_);
committed_ += bytes;
if (committed_ > max_committed_) {
max_committed_ = committed_;
}
}
void AccountUncommitted(size_t bytes) {
DCHECK_GE(committed_, committed_ - bytes);
committed_ -= bytes;
}
protected:
Heap* heap_;
AllocationSpace id_;
// Keeps track of committed memory in a space.
std::atomic<size_t> committed_{0};
size_t max_committed_ = 0;
};
} // namespace internal
} // namespace v8
#endif // V8_HEAP_BASE_SPACE_H_
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