// Copyright 2021 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 INCLUDE_CPPGC_OBJECT_SIZE_TRAIT_H_
#define INCLUDE_CPPGC_OBJECT_SIZE_TRAIT_H_
#include <cstddef>
#include "cppgc/type-traits.h"
#include "v8config.h" // NOLINT(build/include_directory)
namespace cppgc {
namespace internal {
struct V8_EXPORT BaseObjectSizeTrait {
protected:
static size_t GetObjectSizeForGarbageCollected(const void*);
static size_t GetObjectSizeForGarbageCollectedMixin(const void*);
};
} // namespace internal
namespace subtle {
/**
* Trait specifying how to get the size of an object that was allocated using
* `MakeGarbageCollected()`. Also supports querying the size with an inner
* pointer to a mixin.
*/
template <typename T, bool = IsGarbageCollectedMixinTypeV<T>>
struct ObjectSizeTrait;
template <typename T>
struct ObjectSizeTrait<T, false> : cppgc::internal::BaseObjectSizeTrait {
static_assert(sizeof(T), "T must be fully defined");
static_assert(IsGarbageCollectedTypeV<T>,
"T must be of type GarbageCollected or GarbageCollectedMixin");
static size_t GetSize(const T& object) {
return GetObjectSizeForGarbageCollected(&object);
}
};
template <typename T>
struct ObjectSizeTrait<T, true> : cppgc::internal::BaseObjectSizeTrait {
static_assert(sizeof(T), "T must be fully defined");
static size_t GetSize(const T& object) {
return GetObjectSizeForGarbageCollectedMixin(&object);
}
};
} // namespace subtle
} // namespace cppgc
#endif // INCLUDE_CPPGC_OBJECT_SIZE_TRAIT_H_
