cub/util_math.cuh
File members: cub/util_math.cuh
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#pragma once
#include <cub/config.cuh>
#if defined(_CCCL_IMPLICIT_SYSTEM_HEADER_GCC)
# pragma GCC system_header
#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_CLANG)
# pragma clang system_header
#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_MSVC)
# pragma system_header
#endif // no system header
#include <cuda/cmath>
#include <cuda/std/type_traits>
CUB_NAMESPACE_BEGIN
namespace detail
{
template <typename T>
using is_integral_or_enum =
::cuda::std::integral_constant<bool, ::cuda::std::is_integral<T>::value || ::cuda::std::is_enum<T>::value>;
template <typename OffsetT>
_CCCL_HOST_DEVICE _CCCL_FORCEINLINE OffsetT safe_add_bound_to_max(OffsetT lhs, OffsetT rhs)
{
static_assert(::cuda::std::is_integral<OffsetT>::value, "OffsetT must be an integral type");
static_assert(sizeof(OffsetT) >= 4, "OffsetT must be at least 32 bits in size");
auto const capped_operand_rhs = (cub::min)(rhs, ::cuda::std::numeric_limits<OffsetT>::max() - lhs);
return lhs + capped_operand_rhs;
}
} // namespace detail
template <typename NumeratorT, typename DenominatorT>
CUB_DEPRECATED_BECAUSE("Use cuda::ceil_div instead")
_CCCL_HOST_DEVICE _CCCL_FORCEINLINE constexpr NumeratorT DivideAndRoundUp(NumeratorT n, DenominatorT d)
{
static_assert(
cub::detail::is_integral_or_enum<NumeratorT>::value && cub::detail::is_integral_or_enum<DenominatorT>::value,
"DivideAndRoundUp is only intended for integral types.");
return ::cuda::ceil_div(n, d);
}
constexpr _CCCL_HOST_DEVICE int Nominal4BItemsToItemsCombined(int nominal_4b_items_per_thread, int combined_bytes)
{
return (cub::min)(nominal_4b_items_per_thread, (cub::max)(1, nominal_4b_items_per_thread * 8 / combined_bytes));
}
template <typename T>
constexpr _CCCL_HOST_DEVICE int Nominal4BItemsToItems(int nominal_4b_items_per_thread)
{
return (cub::min)(nominal_4b_items_per_thread,
(cub::max)(1, nominal_4b_items_per_thread * 4 / static_cast<int>(sizeof(T))));
}
template <typename ItemT>
constexpr _CCCL_HOST_DEVICE int Nominal8BItemsToItems(int nominal_8b_items_per_thread)
{
return sizeof(ItemT) <= 8u
? nominal_8b_items_per_thread
: (cub::min)(nominal_8b_items_per_thread,
(cub::max)(1,
((nominal_8b_items_per_thread * 8) + static_cast<int>(sizeof(ItemT)) - 1)
/ static_cast<int>(sizeof(ItemT))));
}
template <typename T>
constexpr _CCCL_HOST_DEVICE T MidPoint(T begin, T end)
{
return begin + (end - begin) / 2;
}
CUB_NAMESPACE_END