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#include <thrust/equal.h>
#include <thrust/execution_policy.h>
#include <thrust/iterator/counting_iterator.h>
#include <thrust/iterator/transform_iterator.h>
#include <thrust/reduce.h>
#include <unittest/unittest.h>
#include <cstdint>
template<typename ExecutionPolicy, typename Iterator1, typename Iterator2, typename Iterator3, typename Iterator4, typename Iterator5>
__global__
void reduce_by_key_kernel(ExecutionPolicy exec,
Iterator1 keys_first, Iterator1 keys_last,
Iterator2 values_first,
Iterator3 keys_result,
Iterator4 values_result,
Iterator5 result)
{
*result = thrust::reduce_by_key(exec, keys_first, keys_last, values_first, keys_result, values_result);
}
template<typename ExecutionPolicy, typename Iterator1, typename Iterator2, typename Iterator3, typename Iterator4, typename BinaryPredicate, typename Iterator5>
__global__
void reduce_by_key_kernel(ExecutionPolicy exec,
Iterator1 keys_first, Iterator1 keys_last,
Iterator2 values_first,
Iterator3 keys_result,
Iterator4 values_result,
BinaryPredicate pred,
Iterator5 result)
{
*result = thrust::reduce_by_key(exec, keys_first, keys_last, values_first, keys_result, values_result, pred);
}
template<typename ExecutionPolicy, typename Iterator1, typename Iterator2, typename Iterator3, typename Iterator4, typename BinaryPredicate, typename BinaryFunction, typename Iterator5>
__global__
void reduce_by_key_kernel(ExecutionPolicy exec,
Iterator1 keys_first, Iterator1 keys_last,
Iterator2 values_first,
Iterator3 keys_result,
Iterator4 values_result,
BinaryPredicate pred,
BinaryFunction binary_op,
Iterator5 result)
{
*result = thrust::reduce_by_key(exec, keys_first, keys_last, values_first, keys_result, values_result, pred, binary_op);
}
template<typename T>
struct is_equal_div_10_reduce
{
__host__ __device__
bool operator()(const T x, const T& y) const { return ((int) x / 10) == ((int) y / 10); }
};
template<typename Vector>
void initialize_keys(Vector& keys)
{
keys.resize(9);
keys[0] = 11;
keys[1] = 11;
keys[2] = 21;
keys[3] = 20;
keys[4] = 21;
keys[5] = 21;
keys[6] = 21;
keys[7] = 37;
keys[8] = 37;
}
template<typename Vector>
void initialize_values(Vector& values)
{
values.resize(9);
values[0] = 0;
values[1] = 1;
values[2] = 2;
values[3] = 3;
values[4] = 4;
values[5] = 5;
values[6] = 6;
values[7] = 7;
values[8] = 8;
}
template<typename ExecutionPolicy>
void TestReduceByKeyDevice(ExecutionPolicy exec)
{
typedef int T;
thrust::device_vector<T> keys;
thrust::device_vector<T> values;
typedef typename thrust::pair<
typename thrust::device_vector<T>::iterator,
typename thrust::device_vector<T>::iterator
> iterator_pair;
thrust::device_vector<iterator_pair> new_last_vec(1);
iterator_pair new_last;
// basic test
initialize_keys(keys); initialize_values(values);
thrust::device_vector<T> output_keys(keys.size());
thrust::device_vector<T> output_values(values.size());
reduce_by_key_kernel<<<1,1>>>(exec, keys.begin(), keys.end(), values.begin(), output_keys.begin(), output_values.begin(), new_last_vec.begin());
{
cudaError_t const err = cudaDeviceSynchronize();
ASSERT_EQUAL(cudaSuccess, err);
}
new_last = new_last_vec[0];
ASSERT_EQUAL(new_last.first - output_keys.begin(), 5);
ASSERT_EQUAL(new_last.second - output_values.begin(), 5);
ASSERT_EQUAL(output_keys[0], 11);
ASSERT_EQUAL(output_keys[1], 21);
ASSERT_EQUAL(output_keys[2], 20);
ASSERT_EQUAL(output_keys[3], 21);
ASSERT_EQUAL(output_keys[4], 37);
ASSERT_EQUAL(output_values[0], 1);
ASSERT_EQUAL(output_values[1], 2);
ASSERT_EQUAL(output_values[2], 3);
ASSERT_EQUAL(output_values[3], 15);
ASSERT_EQUAL(output_values[4], 15);
// test BinaryPredicate
initialize_keys(keys); initialize_values(values);
reduce_by_key_kernel<<<1,1>>>(exec, keys.begin(), keys.end(), values.begin(), output_keys.begin(), output_values.begin(), is_equal_div_10_reduce<T>(), new_last_vec.begin());
{
cudaError_t const err = cudaDeviceSynchronize();
ASSERT_EQUAL(cudaSuccess, err);
}
new_last = new_last_vec[0];
ASSERT_EQUAL(new_last.first - output_keys.begin(), 3);
ASSERT_EQUAL(new_last.second - output_values.begin(), 3);
ASSERT_EQUAL(output_keys[0], 11);
ASSERT_EQUAL(output_keys[1], 21);
ASSERT_EQUAL(output_keys[2], 37);
ASSERT_EQUAL(output_values[0], 1);
ASSERT_EQUAL(output_values[1], 20);
ASSERT_EQUAL(output_values[2], 15);
// test BinaryFunction
initialize_keys(keys); initialize_values(values);
reduce_by_key_kernel<<<1,1>>>(exec, keys.begin(), keys.end(), values.begin(), output_keys.begin(), output_values.begin(), thrust::equal_to<T>(), thrust::plus<T>(), new_last_vec.begin());
{
cudaError_t const err = cudaDeviceSynchronize();
ASSERT_EQUAL(cudaSuccess, err);
}
new_last = new_last_vec[0];
ASSERT_EQUAL(new_last.first - output_keys.begin(), 5);
ASSERT_EQUAL(new_last.second - output_values.begin(), 5);
ASSERT_EQUAL(output_keys[0], 11);
ASSERT_EQUAL(output_keys[1], 21);
ASSERT_EQUAL(output_keys[2], 20);
ASSERT_EQUAL(output_keys[3], 21);
ASSERT_EQUAL(output_keys[4], 37);
ASSERT_EQUAL(output_values[0], 1);
ASSERT_EQUAL(output_values[1], 2);
ASSERT_EQUAL(output_values[2], 3);
ASSERT_EQUAL(output_values[3], 15);
ASSERT_EQUAL(output_values[4], 15);
}
void TestReduceByKeyDeviceSeq()
{
TestReduceByKeyDevice(thrust::seq);
}
DECLARE_UNITTEST(TestReduceByKeyDeviceSeq);
void TestReduceByKeyDeviceDevice()
{
TestReduceByKeyDevice(thrust::device);
}
DECLARE_UNITTEST(TestReduceByKeyDeviceDevice);
void TestReduceByKeyDeviceNoSync()
{
TestReduceByKeyDevice(thrust::cuda::par_nosync);
}
DECLARE_UNITTEST(TestReduceByKeyDeviceNoSync);
template<typename ExecutionPolicy>
void TestReduceByKeyCudaStreams(ExecutionPolicy policy)
{
typedef thrust::device_vector<int> Vector;
typedef Vector::value_type T;
Vector keys;
Vector values;
thrust::pair<Vector::iterator, Vector::iterator> new_last;
// basic test
initialize_keys(keys); initialize_values(values);
Vector output_keys(keys.size());
Vector output_values(values.size());
cudaStream_t s;
cudaStreamCreate(&s);
auto streampolicy = policy.on(s);
new_last = thrust::reduce_by_key(streampolicy, keys.begin(), keys.end(), values.begin(), output_keys.begin(), output_values.begin());
ASSERT_EQUAL(new_last.first - output_keys.begin(), 5);
ASSERT_EQUAL(new_last.second - output_values.begin(), 5);
ASSERT_EQUAL(output_keys[0], 11);
ASSERT_EQUAL(output_keys[1], 21);
ASSERT_EQUAL(output_keys[2], 20);
ASSERT_EQUAL(output_keys[3], 21);
ASSERT_EQUAL(output_keys[4], 37);
ASSERT_EQUAL(output_values[0], 1);
ASSERT_EQUAL(output_values[1], 2);
ASSERT_EQUAL(output_values[2], 3);
ASSERT_EQUAL(output_values[3], 15);
ASSERT_EQUAL(output_values[4], 15);
// test BinaryPredicate
initialize_keys(keys); initialize_values(values);
new_last = thrust::reduce_by_key(streampolicy, keys.begin(), keys.end(), values.begin(), output_keys.begin(), output_values.begin(), is_equal_div_10_reduce<T>());
ASSERT_EQUAL(new_last.first - output_keys.begin(), 3);
ASSERT_EQUAL(new_last.second - output_values.begin(), 3);
ASSERT_EQUAL(output_keys[0], 11);
ASSERT_EQUAL(output_keys[1], 21);
ASSERT_EQUAL(output_keys[2], 37);
ASSERT_EQUAL(output_values[0], 1);
ASSERT_EQUAL(output_values[1], 20);
ASSERT_EQUAL(output_values[2], 15);
// test BinaryFunction
initialize_keys(keys); initialize_values(values);
new_last = thrust::reduce_by_key(streampolicy, keys.begin(), keys.end(), values.begin(), output_keys.begin(), output_values.begin(), thrust::equal_to<T>(), thrust::plus<T>());
ASSERT_EQUAL(new_last.first - output_keys.begin(), 5);
ASSERT_EQUAL(new_last.second - output_values.begin(), 5);
ASSERT_EQUAL(output_keys[0], 11);
ASSERT_EQUAL(output_keys[1], 21);
ASSERT_EQUAL(output_keys[2], 20);
ASSERT_EQUAL(output_keys[3], 21);
ASSERT_EQUAL(output_keys[4], 37);
ASSERT_EQUAL(output_values[0], 1);
ASSERT_EQUAL(output_values[1], 2);
ASSERT_EQUAL(output_values[2], 3);
ASSERT_EQUAL(output_values[3], 15);
ASSERT_EQUAL(output_values[4], 15);
cudaStreamDestroy(s);
}
void TestReduceByKeyCudaStreamsSync()
{
TestReduceByKeyCudaStreams(thrust::cuda::par);
}
DECLARE_UNITTEST(TestReduceByKeyCudaStreamsSync);
void TestReduceByKeyCudaStreamsNoSync()
{
TestReduceByKeyCudaStreams(thrust::cuda::par_nosync);
}
DECLARE_UNITTEST(TestReduceByKeyCudaStreamsNoSync);
// Maps indices to key ids
class div_op : public thrust::unary_function<std::int64_t, std::int64_t>
{
std::int64_t m_divisor;
public:
__host__ div_op(std::int64_t divisor)
: m_divisor(divisor)
{}
__host__ __device__
std::int64_t operator()(std::int64_t x) const
{
return x / m_divisor;
}
};
// Produces unique sequence for key
class mod_op : public thrust::unary_function<std::int64_t, std::int64_t>
{
std::int64_t m_divisor;
public:
__host__ mod_op(std::int64_t divisor)
: m_divisor(divisor)
{}
__host__ __device__
std::int64_t operator()(std::int64_t x) const
{
// div: 2
// idx: 0 1 2 3 4 5
// key: 0 0 | 1 1 | 2 2
// mod: 0 1 | 0 1 | 0 1
// ret: 0 1 1 2 2 3
return (x % m_divisor) + (x / m_divisor);
}
};
void TestReduceByKeyWithBigIndexesHelper(int magnitude)
{
const std::int64_t key_size_magnitude = 8;
ASSERT_EQUAL(true, key_size_magnitude < magnitude);
const std::int64_t num_items = 1ll << magnitude;
const std::int64_t num_unique_keys = 1ll << key_size_magnitude;
// Size of each key group
const std::int64_t key_size = num_items / num_unique_keys;
using counting_it = thrust::counting_iterator<std::int64_t>;
using transform_key_it = thrust::transform_iterator<div_op, counting_it>;
using transform_val_it = thrust::transform_iterator<mod_op, counting_it>;
counting_it count_begin(0ll);
counting_it count_end = count_begin + num_items;
ASSERT_EQUAL(static_cast<std::int64_t>(thrust::distance(count_begin, count_end)),
num_items);
transform_key_it keys_begin(count_begin, div_op{key_size});
transform_key_it keys_end(count_end, div_op{key_size});
transform_val_it values_begin(count_begin, mod_op{key_size});
thrust::device_vector<std::int64_t> output_keys(num_unique_keys);
thrust::device_vector<std::int64_t> output_values(num_unique_keys);
// example:
// items: 6
// unique_keys: 2
// key_size: 3
// keys: 0 0 0 | 1 1 1
// values: 0 1 2 | 1 2 3
// result: 3 6 = sum(range(key_size)) + key_size * key_id
thrust::reduce_by_key(keys_begin,
keys_end,
values_begin,
output_keys.begin(),
output_values.begin());
ASSERT_EQUAL(
true,
thrust::equal(output_keys.begin(), output_keys.end(), count_begin));
thrust::host_vector<std::int64_t> result = output_values;
const std::int64_t sum = (key_size - 1) * key_size / 2;
for (std::int64_t key_id = 0; key_id < num_unique_keys; key_id++)
{
ASSERT_EQUAL(result[key_id], sum + key_id * key_size);
}
}
void TestReduceByKeyWithBigIndexes()
{
TestReduceByKeyWithBigIndexesHelper(30);
TestReduceByKeyWithBigIndexesHelper(31);
TestReduceByKeyWithBigIndexesHelper(32);
TestReduceByKeyWithBigIndexesHelper(33);
}
DECLARE_UNITTEST(TestReduceByKeyWithBigIndexes);
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