xref: /llvm-project/pstl/test/std/numerics/numeric.ops/scan.pass.cpp (revision 3b9a1bb1af90db9472340ef2122d3855eb9ba3fc)
1 // -*- C++ -*-
2 //===-- scan.pass.cpp -----------------------------------------------------===//
3 //
4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 // See https://llvm.org/LICENSE.txt for license information.
6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //
8 //===----------------------------------------------------------------------===//
9 
10 // UNSUPPORTED: c++03, c++11, c++14
11 
12 #include "support/pstl_test_config.h"
13 
14 #include <execution>
15 #include <numeric>
16 
17 #include "support/utils.h"
18 
19 using namespace TestUtils;
20 
21 // We provide the no execution policy versions of the exclusive_scan and inclusive_scan due checking correctness result of the versions with execution policies.
22 //TODO: to add a macro for availability of ver implementations
23 template <class InputIterator, class OutputIterator, class T>
24 OutputIterator
exclusive_scan_serial(InputIterator first,InputIterator last,OutputIterator result,T init)25 exclusive_scan_serial(InputIterator first, InputIterator last, OutputIterator result, T init)
26 {
27     for (; first != last; ++first, ++result)
28     {
29         *result = init;
30         init = init + *first;
31     }
32     return result;
33 }
34 
35 template <class InputIterator, class OutputIterator, class T, class BinaryOperation>
36 OutputIterator
exclusive_scan_serial(InputIterator first,InputIterator last,OutputIterator result,T init,BinaryOperation binary_op)37 exclusive_scan_serial(InputIterator first, InputIterator last, OutputIterator result, T init, BinaryOperation binary_op)
38 {
39     for (; first != last; ++first, ++result)
40     {
41         *result = init;
42         init = binary_op(init, *first);
43     }
44     return result;
45 }
46 
47 // Note: N4582 is missing the ", class T".  Issue was reported 2016-Apr-11 to cxxeditor@gmail.com
48 template <class InputIterator, class OutputIterator, class BinaryOperation, class T>
49 OutputIterator
inclusive_scan_serial(InputIterator first,InputIterator last,OutputIterator result,BinaryOperation binary_op,T init)50 inclusive_scan_serial(InputIterator first, InputIterator last, OutputIterator result, BinaryOperation binary_op, T init)
51 {
52     for (; first != last; ++first, ++result)
53     {
54         init = binary_op(init, *first);
55         *result = init;
56     }
57     return result;
58 }
59 
60 template <class InputIterator, class OutputIterator, class BinaryOperation>
61 OutputIterator
inclusive_scan_serial(InputIterator first,InputIterator last,OutputIterator result,BinaryOperation binary_op)62 inclusive_scan_serial(InputIterator first, InputIterator last, OutputIterator result, BinaryOperation binary_op)
63 {
64     if (first != last)
65     {
66         auto tmp = *first;
67         *result = tmp;
68         return inclusive_scan_serial(++first, last, ++result, binary_op, tmp);
69     }
70     else
71     {
72         return result;
73     }
74 }
75 
76 template <class InputIterator, class OutputIterator>
77 OutputIterator
inclusive_scan_serial(InputIterator first,InputIterator last,OutputIterator result)78 inclusive_scan_serial(InputIterator first, InputIterator last, OutputIterator result)
79 {
80     typedef typename std::iterator_traits<InputIterator>::value_type input_type;
81     return inclusive_scan_serial(first, last, result, std::plus<input_type>());
82 }
83 
84 // Most of the framework required for testing inclusive and exclusive scan is identical,
85 // so the tests for both are in this file.  Which is being tested is controlled by the global
86 // flag inclusive, which is set to each alternative by main().
87 static bool inclusive;
88 
89 template <typename Iterator, typename Size, typename T>
90 void
check_and_reset(Iterator expected_first,Iterator out_first,Size n,T trash)91 check_and_reset(Iterator expected_first, Iterator out_first, Size n, T trash)
92 {
93     EXPECT_EQ_N(expected_first, out_first, n,
94                 inclusive ? "wrong result from inclusive_scan" : "wrong result from exclusive_scan");
95     std::fill_n(out_first, n, trash);
96 }
97 
98 struct test_scan_with_plus
99 {
100     template <typename Policy, typename Iterator1, typename Iterator2, typename Iterator3, typename Size, typename T>
101     void
operator ()test_scan_with_plus102     operator()(Policy&& exec, Iterator1 in_first, Iterator1 in_last, Iterator2 out_first, Iterator2 out_last,
103                Iterator3 expected_first, Iterator3, Size n, T init, T trash)
104     {
105         using namespace std;
106 
107         auto orr1 = inclusive ? inclusive_scan_serial(in_first, in_last, expected_first)
108                               : exclusive_scan_serial(in_first, in_last, expected_first, init);
109         (void)orr1;
110         auto orr = inclusive ? inclusive_scan(exec, in_first, in_last, out_first)
111                              : exclusive_scan(exec, in_first, in_last, out_first, init);
112         EXPECT_TRUE(out_last == orr,
113                     inclusive ? "inclusive_scan returned wrong iterator" : "exclusive_scan returned wrong iterator");
114 
115         check_and_reset(expected_first, out_first, n, trash);
116         fill(out_first, out_last, trash);
117     }
118 };
119 
120 template <typename T, typename Convert>
121 void
test_with_plus(T init,T trash,Convert convert)122 test_with_plus(T init, T trash, Convert convert)
123 {
124     for (size_t n = 0; n <= 100000; n = n <= 16 ? n + 1 : size_t(3.1415 * n))
125     {
126         Sequence<T> in(n, convert);
127         Sequence<T> expected(in);
128         Sequence<T> out(n, [&](int32_t) { return trash; });
129 
130         invoke_on_all_policies(test_scan_with_plus(), in.begin(), in.end(), out.begin(), out.end(), expected.begin(),
131                                expected.end(), in.size(), init, trash);
132         invoke_on_all_policies(test_scan_with_plus(), in.cbegin(), in.cend(), out.begin(), out.end(), expected.begin(),
133                                expected.end(), in.size(), init, trash);
134     }
135 }
136 struct test_scan_with_binary_op
137 {
138     template <typename Policy, typename Iterator1, typename Iterator2, typename Iterator3, typename Size, typename T,
139               typename BinaryOp>
140     typename std::enable_if<!TestUtils::isReverse<Iterator1>::value, void>::type
operator ()test_scan_with_binary_op141     operator()(Policy&& exec, Iterator1 in_first, Iterator1 in_last, Iterator2 out_first, Iterator2 out_last,
142                Iterator3 expected_first, Iterator3, Size n, T init, BinaryOp binary_op, T trash)
143     {
144         using namespace std;
145 
146         auto orr1 = inclusive ? inclusive_scan_serial(in_first, in_last, expected_first, binary_op, init)
147                               : exclusive_scan_serial(in_first, in_last, expected_first, init, binary_op);
148         (void)orr1;
149         auto orr = inclusive ? inclusive_scan(exec, in_first, in_last, out_first, binary_op, init)
150                              : exclusive_scan(exec, in_first, in_last, out_first, init, binary_op);
151 
152         EXPECT_TRUE(out_last == orr, "scan returned wrong iterator");
153         check_and_reset(expected_first, out_first, n, trash);
154     }
155 
156     template <typename Policy, typename Iterator1, typename Iterator2, typename Iterator3, typename Size, typename T,
157               typename BinaryOp>
158     typename std::enable_if<TestUtils::isReverse<Iterator1>::value, void>::type
operator ()test_scan_with_binary_op159     operator()(Policy&&, Iterator1, Iterator1, Iterator2, Iterator2, Iterator3, Iterator3, Size, T, BinaryOp, T)
160     {
161     }
162 };
163 
164 template <typename In, typename Out, typename BinaryOp>
165 void
test_matrix(Out init,BinaryOp binary_op,Out trash)166 test_matrix(Out init, BinaryOp binary_op, Out trash)
167 {
168     for (size_t n = 0; n <= 100000; n = n <= 16 ? n + 1 : size_t(3.1415 * n))
169     {
170         Sequence<In> in(n, [](size_t k) { return In(k, k + 1); });
171 
172         Sequence<Out> out(n, [&](size_t) { return trash; });
173         Sequence<Out> expected(n, [&](size_t) { return trash; });
174 
175         invoke_on_all_policies(test_scan_with_binary_op(), in.begin(), in.end(), out.begin(), out.end(),
176                                expected.begin(), expected.end(), in.size(), init, binary_op, trash);
177         invoke_on_all_policies(test_scan_with_binary_op(), in.cbegin(), in.cend(), out.begin(), out.end(),
178                                expected.begin(), expected.end(), in.size(), init, binary_op, trash);
179     }
180 }
181 
182 int
main()183 main()
184 {
185     for (int32_t mode = 0; mode < 2; ++mode)
186     {
187         inclusive = mode != 0;
188 #if !defined(_PSTL_ICC_19_TEST_SIMD_UDS_WINDOWS_RELEASE_BROKEN)
189         // Test with highly restricted type and associative but not commutative operation
190         test_matrix<Matrix2x2<int32_t>, Matrix2x2<int32_t>>(Matrix2x2<int32_t>(), multiply_matrix<int32_t>,
191                                                             Matrix2x2<int32_t>(-666, 666));
192 #endif
193 
194         // Since the implict "+" forms of the scan delegate to the generic forms,
195         // there's little point in using a highly restricted type, so just use double.
196         test_with_plus<float64_t>(inclusive ? 0.0 : -1.0, -666.0,
197                                   [](uint32_t k) { return float64_t((k % 991 + 1) ^ (k % 997 + 2)); });
198     }
199     std::cout << done() << std::endl;
200     return 0;
201 }
202