126 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++11, c++1410 11// <numeric>12 13// Became constexpr in C++2014// template<class InputIterator, class OutputIterator, class T, class BinaryOperation>15// OutputIterator16// inclusive_scan(InputIterator first, InputIterator last,17// OutputIterator result,18// BinaryOperation binary_op); // C++1719 20#include <algorithm>21#include <array>22#include <cassert>23#include <cstddef>24#include <functional>25#include <numeric>26 27#include "test_macros.h"28#include "test_iterators.h"29 30template <class Iter1, class Op, class T>31TEST_CONSTEXPR_CXX20 void32test(Iter1 first, Iter1 last, Op op, const T *rFirst, const T *rLast)33{34 assert((rLast - rFirst) <= 5); // or else increase the size of "out"35 T out[5];36 37 // Not in place38 T *end = std::inclusive_scan(first, last, out, op);39 assert(std::equal(out, end, rFirst, rLast));40 41 // In place42 std::copy(first, last, out);43 end = std::inclusive_scan(out, end, out, op);44 assert(std::equal(out, end, rFirst, rLast));45}46 47 48template <class Iter>49TEST_CONSTEXPR_CXX20 void50test()51{52 int ia[] = {1, 3, 5, 7, 9};53 const int pRes[] = {1, 4, 9, 16, 25};54 const int mRes[] = {1, 3, 15, 105, 945};55 const unsigned sa = sizeof(ia) / sizeof(ia[0]);56 static_assert(sa == sizeof(pRes) / sizeof(pRes[0])); // just to be sure57 static_assert(sa == sizeof(mRes) / sizeof(mRes[0])); // just to be sure58 59 for (unsigned int i = 0; i < sa; ++i ) {60 test(Iter(ia), Iter(ia + i), std::plus<>(), pRes, pRes + i);61 test(Iter(ia), Iter(ia + i), std::multiplies<>(), mRes, mRes + i);62 }63}64 65constexpr std::size_t triangle(size_t n) { return n*(n+1)/2; }66 67// Basic sanity68TEST_CONSTEXPR_CXX20 void69basic_tests()70{71 {72 std::array<std::size_t, 10> v;73 std::fill(v.begin(), v.end(), 3);74 std::inclusive_scan(v.begin(), v.end(), v.begin(), std::plus<>());75 for (std::size_t i = 0; i < v.size(); ++i)76 assert(v[i] == (i+1) * 3);77 }78 79 {80 std::array<std::size_t, 10> v;81 std::iota(v.begin(), v.end(), 0);82 std::inclusive_scan(v.begin(), v.end(), v.begin(), std::plus<>());83 for (std::size_t i = 0; i < v.size(); ++i)84 assert(v[i] == triangle(i));85 }86 87 {88 std::array<std::size_t, 10> v;89 std::iota(v.begin(), v.end(), 1);90 std::inclusive_scan(v.begin(), v.end(), v.begin(), std::plus<>());91 for (std::size_t i = 0; i < v.size(); ++i)92 assert(v[i] == triangle(i + 1));93 }94 95 {96 std::array<std::size_t, 0> v, res;97 std::inclusive_scan(v.begin(), v.end(), res.begin(), std::plus<>());98 assert(res.empty());99 }100}101 102TEST_CONSTEXPR_CXX20 bool103test()104{105 basic_tests();106 107// All the iterator categories108 test<cpp17_input_iterator <const int*> >();109 test<forward_iterator <const int*> >();110 test<bidirectional_iterator<const int*> >();111 test<random_access_iterator<const int*> >();112 test<const int*>();113 test< int*>();114 115 return true;116}117 118int main(int, char**)119{120 test();121#if TEST_STD_VER > 17122 static_assert(test());123#endif124 return 0;125}126