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Fix hash to size conversion #362

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Fix hash to size conversion #362

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12 changes: 6 additions & 6 deletions include/cuco/detail/probing_scheme_impl.inl
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Original file line number Diff line number Diff line change
Expand Up @@ -100,7 +100,7 @@ __host__ __device__ constexpr auto linear_probing<CGSize, Hash>::operator()(
{
using size_type = typename Extent::value_type;
return detail::probing_iterator<Extent>{
cuco::detail::sanitize_hash<size_type>(hash_(probe_key)) % upper_bound,
cuco::detail::hash_to_index<size_type>(hash_(probe_key)) % upper_bound,
1, // step size is 1
upper_bound};
}
Expand All @@ -114,7 +114,7 @@ __host__ __device__ constexpr auto linear_probing<CGSize, Hash>::operator()(
{
using size_type = typename Extent::value_type;
return detail::probing_iterator<Extent>{
cuco::detail::sanitize_hash<size_type>(hash_(probe_key) + g.thread_rank()) % upper_bound,
cuco::detail::hash_to_index<size_type>(hash_(probe_key), g.thread_rank()) % upper_bound,
cg_size,
upper_bound};
}
Expand All @@ -133,9 +133,9 @@ __host__ __device__ constexpr auto double_hashing<CGSize, Hash1, Hash2>::operato
{
using size_type = typename Extent::value_type;
return detail::probing_iterator<Extent>{
cuco::detail::sanitize_hash<size_type>(hash1_(probe_key)) % upper_bound,
cuco::detail::hash_to_index<size_type>(hash1_(probe_key)) % upper_bound,
max(size_type{1},
cuco::detail::sanitize_hash<size_type>(hash2_(probe_key)) %
cuco::detail::hash_to_index<size_type>(hash2_(probe_key)) %
upper_bound), // step size in range [1, prime - 1]
upper_bound};
}
Expand All @@ -149,8 +149,8 @@ __host__ __device__ constexpr auto double_hashing<CGSize, Hash1, Hash2>::operato
{
using size_type = typename Extent::value_type;
return detail::probing_iterator<Extent>{
cuco::detail::sanitize_hash<size_type>(hash1_(probe_key) + g.thread_rank()) % upper_bound,
static_cast<size_type>((cuco::detail::sanitize_hash<size_type>(hash2_(probe_key)) %
cuco::detail::hash_to_index<size_type>(hash1_(probe_key), g.thread_rank()) % upper_bound,
static_cast<size_type>((cuco::detail::hash_to_index<size_type>(hash2_(probe_key)) %
(upper_bound.value() / cg_size - 1) +
1) *
cg_size),
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16 changes: 12 additions & 4 deletions include/cuco/detail/utils.cuh
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Original file line number Diff line number Diff line change
Expand Up @@ -112,15 +112,23 @@ struct strong_type {
* @tparam SizeType The target type
* @tparam HashType The input type
*
* @param[in] hash The hash value
* @param[in] thread_rank Local thread offset during CG probing
*
* @return Converted hash value
*/
template <typename SizeType, typename HashType>
__host__ __device__ constexpr SizeType sanitize_hash(HashType hash) noexcept
__host__ __device__ constexpr SizeType hash_to_index(HashType hash,
uint32_t thread_rank = 0) noexcept
{
if constexpr (cuda::std::is_signed_v<SizeType>) {
return cuda::std::abs(static_cast<SizeType>(hash));
if constexpr (std::is_unsigned_v<SizeType>) {
constexpr auto max_size = static_cast<HashType>(cuda::std::numeric_limits<SizeType>::max());
return static_cast<SizeType>((hash + thread_rank) & max_size);
} else {
return static_cast<SizeType>(hash);
using larger_type =
cuda::std::conditional_t<sizeof(HashType) >= sizeof(SizeType), HashType, SizeType>;
constexpr auto max_size = static_cast<larger_type>(cuda::std::numeric_limits<SizeType>::max());
return static_cast<SizeType>((hash & max_size + thread_rank) & max_size);
}
}

Expand Down