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/*
* Copyright (C) 2010 Google Inc. All rights reserved.
* Copyright (C) 2017 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include <type_traits>
#include <utility>
#include <wtf/Assertions.h>
#include <wtf/RefCounted.h>
#include <wtf/RefPtr.h>
#include <wtf/Vector.h>
namespace WTF {
#if !defined(NDEBUG) || ENABLE(SECURITY_ASSERTIONS)
struct SameSizeAsRefCounted {
int a;
bool b;
bool c;
bool d;
bool e;
// The debug version may get bigger.
};
#else
struct SameSizeAsRefCounted {
int a;
// Don't add anything here because this should stay small.
};
#endif
static_assert(sizeof(RefCounted<int>) == sizeof(SameSizeAsRefCounted), "RefCounted should stay small!");
static_assert(sizeof(RefPtr<RefCounted<int>>) == sizeof(int*), "RefPtr should stay small!");
#if !ASAN_ENABLED
template<typename T, unsigned inlineCapacity = 0>
struct SameSizeAsVectorWithInlineCapacity;
template<typename T>
struct SameSizeAsVectorWithInlineCapacity<T, 0> {
WTF_MAKE_NONCOPYABLE(SameSizeAsVectorWithInlineCapacity);
public:
void* bufferPointer;
unsigned capacity;
unsigned size;
};
template<typename T>
struct SameSizeAsVectorWithInlineCapacityBase : SameSizeAsVectorWithInlineCapacity<T> {
};
template<typename T, unsigned inlineCapacity>
struct SameSizeAsVectorWithInlineCapacity : SameSizeAsVectorWithInlineCapacityBase<T> {
WTF_MAKE_NONCOPYABLE(SameSizeAsVectorWithInlineCapacity);
public:
typename std::aligned_storage<sizeof(T), std::alignment_of<T>::value>::type inlineBuffer[inlineCapacity];
};
static_assert(sizeof(Vector<int>) == sizeof(SameSizeAsVectorWithInlineCapacity<int>), "Vector should stay small!");
static_assert(sizeof(Vector<int, 1>) == sizeof(SameSizeAsVectorWithInlineCapacity<int, 1>), "Vector should stay small!");
static_assert(sizeof(Vector<int, 2>) == sizeof(SameSizeAsVectorWithInlineCapacity<int, 2>), "Vector should stay small!");
static_assert(sizeof(Vector<int, 3>) == sizeof(SameSizeAsVectorWithInlineCapacity<int, 3>), "Vector should stay small!");
#endif
}