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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++98, c++03, c++11
// <experimental/any>
// Check that the size and alignment of any are what we expect.
#include <experimental/any>
#include "any_helpers.h"
constexpr std::size_t BufferSize = (sizeof(void*) * 3);
constexpr std::size_t BufferAlignment = alignof(void*);
// Clang doesn't like "alignof(BufferAlignment * 2)" due to PR13986.
// So we create "DoubleBufferAlignment" instead.
constexpr std::size_t DoubleBufferAlignment = BufferAlignment * 2;
class SmallThrowsDtor
{
public:
SmallThrowsDtor() {}
SmallThrowsDtor(SmallThrowsDtor const &) noexcept {}
SmallThrowsDtor(SmallThrowsDtor &&) noexcept {}
~SmallThrowsDtor() noexcept(false) {}
};
struct alignas(1) MaxSizeType {
char buff[BufferSize];
};
struct alignas(BufferAlignment) MaxAlignType {
};
struct alignas(BufferAlignment) MaxSizeAndAlignType {
char buff[BufferSize];
};
struct alignas(1) OverSizeType {
char buff[BufferSize + 1];
};
struct alignas(DoubleBufferAlignment) OverAlignedType {
};
struct alignas(DoubleBufferAlignment) OverSizeAndAlignedType {
char buff[BufferSize + 1];
};
int main()
{
using std::experimental::any;
using std::experimental::__any_imp::_IsSmallObject;
static_assert(_IsSmallObject<small>::value, "");
static_assert(_IsSmallObject<void*>::value, "");
static_assert(!_IsSmallObject<SmallThrowsDtor>::value, "");
static_assert(!_IsSmallObject<large>::value, "");
{
// Check a type that meets the size requirement *exactly* and has
// a lesser alignment requirement is considered small.
typedef MaxSizeType T;
static_assert(sizeof(T) == BufferSize, "");
static_assert(alignof(T) < BufferAlignment, "");
static_assert(_IsSmallObject<T>::value, "");
}
{
// Check a type that meets the alignment requirement *exactly* and has
// a lesser size is considered small.
typedef MaxAlignType T;
static_assert(sizeof(T) < BufferSize, "");
static_assert(alignof(T) == BufferAlignment, "");
static_assert(_IsSmallObject<T>::value, "");
}
{
// Check a type that meets the size and alignment requirements *exactly*
// is considered small.
typedef MaxSizeAndAlignType T;
static_assert(sizeof(T) == BufferSize, "");
static_assert(alignof(T) == BufferAlignment, "");
static_assert(_IsSmallObject<T>::value, "");
}
{
// Check a type that meets the alignment requirements but is over-sized
// is not considered small.
typedef OverSizeType T;
static_assert(sizeof(T) > BufferSize, "");
static_assert(alignof(T) < BufferAlignment, "");
static_assert(!_IsSmallObject<T>::value, "");
}
{
// Check a type that meets the size requirements but is over-aligned
// is not considered small.
typedef OverAlignedType T;
static_assert(sizeof(T) < BufferSize, "");
static_assert(alignof(T) > BufferAlignment, "");
static_assert(!_IsSmallObject<T>::value, "");
}
{
// Check a type that exceeds both the size an alignment requirements
// is not considered small.
typedef OverSizeAndAlignedType T;
static_assert(sizeof(T) > BufferSize, "");
static_assert(alignof(T) > BufferAlignment, "");
static_assert(!_IsSmallObject<T>::value, "");
}
}
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