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// Copyright (C) 2020-2025 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
// expensive: * [1-9] * *
#include "bits/main.h"
template <typename V>
void
test()
{
using T = typename V::value_type;
// V must store V::size() values of type T giving us the lower bound on the
// sizeof
VERIFY(sizeof(V) >= sizeof(T) * V::size());
// For fixed_size, V should not pad more than to the next-power-of-2 of
// sizeof(T) * V::size() (for ABI stability of V), giving us the upper bound
// on the sizeof. For non-fixed_size we give the implementation a bit more
// slack to trade space vs. efficiency.
auto n = sizeof(T) * V::size();
if (n & (n - 1))
{
n = ((n << 1) & ~n) & ~((n >> 1) | (n >> 3));
while (n & (n - 1))
n &= n - 1;
}
if constexpr (
!std::is_same_v<typename V::abi_type,
std::experimental::simd_abi::fixed_size<V::size()>>)
n *= 2;
VERIFY(sizeof(V) <= n) << "\nsizeof(V): " << sizeof(V) << "\nn: " << n;
}
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