virtualx-engine/thirdparty/embree/common/algorithms/parallel_partition.cpp
2021-01-14 18:02:07 +01:00

53 lines
1.9 KiB
C++

// Copyright 2009-2020 Intel Corporation
// SPDX-License-Identifier: Apache-2.0
#include "parallel_partition.h"
#include "../sys/regression.h"
namespace embree
{
struct parallel_partition_regression_test : public RegressionTest
{
parallel_partition_regression_test(const char* name) : RegressionTest(name) {
registerRegressionTest(this);
}
bool run ()
{
bool passed = true;
for (size_t i=0; i<100; i++)
{
/* create random permutation */
size_t N = std::rand() % 1000000;
std::vector<unsigned> array(N);
for (unsigned i=0; i<N; i++) array[i] = i;
for (auto& v : array) std::swap(v,array[std::rand()%array.size()]);
size_t split = std::rand() % (N+1);
/* perform parallel partitioning */
size_t left_sum = 0, right_sum = 0;
size_t mid = parallel_partitioning(array.data(),0,array.size(),0,left_sum,right_sum,
[&] ( size_t i ) { return i < split; },
[] ( size_t& sum, unsigned v) { sum += v; },
[] ( size_t& sum, size_t v) { sum += v; },
128);
/*serial_partitioning(array.data(),0,array.size(),left_sum,right_sum,
[&] ( size_t i ) { return i < split; },
[] ( size_t& left_sum, int v) { left_sum += v; });*/
/* verify result */
passed &= mid == split;
passed &= left_sum == split*(split-1)/2;
passed &= right_sum == N*(N-1)/2-left_sum;
for (size_t i=0; i<split; i++) passed &= array[i] < split;
for (size_t i=split; i<N; i++) passed &= array[i] >= split;
}
return passed;
}
};
parallel_partition_regression_test parallel_partition_regression("parallel_partition_regression_test");
}