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// { dg-options "-std=gnu++17" }
// { dg-do run { target *-*-* } }
// { dg-require-effective-target c++17 }
// { dg-additional-options "-march=x86-64-v4" { target avx512f_runtime } }
// { dg-require-cmath "" }
#include <experimental/simd>
namespace stdx = std::experimental;
using T = std::uint64_t;
template <typename U, int N>
using V = stdx::simd<U, stdx::simd_abi::deduce_t<U, N>>;
[[gnu::noinline, gnu::noipa]]
int reduce(V<T, 4> x)
{
static_assert(stdx::find_last_set(V<T, 4>([](unsigned i) { return i; }) != V<T, 4>(0)) == 3);
return stdx::find_last_set(x != -1);
}
[[gnu::noinline, gnu::noipa]]
int reduce2()
{
using M8 = typename V<short, 8>::mask_type;
using M4 = typename V<int, 4>::mask_type;
if constexpr (sizeof(M8) == sizeof(M4)
&& !std::is_same_v<M4, stdx::fixed_size_simd_mask<int, 4>>)
// fixed_size invariant: padding bits of masks are zero, the memcpy would violate that
{
M4 k;
__builtin_memcpy(&__data(k), &__data(M8(true)), sizeof(M4));
return stdx::find_last_set(k);
}
return 3;
}
int main()
{
const V<T, 4> x {};
const int r = reduce(x);
if (r != 3)
__builtin_abort();
const int r2 = reduce2();
if (r2 != 3)
__builtin_abort();
}
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