1 // -*- C++ -*-
2 //===-- remove_copy.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 <algorithm>
16 
17 #include "support/utils.h"
18 
19 using namespace TestUtils;
20 
21 struct run_remove_copy
22 {
23     template <typename Policy, typename InputIterator, typename OutputIterator, typename OutputIterator2, typename Size,
24               typename T>
25     void
26     operator()(Policy&& exec, InputIterator first, InputIterator last, OutputIterator out_first,
27                OutputIterator out_last, OutputIterator2 expected_first, OutputIterator2, Size n, const T& value,
28                T trash)
29     {
30         // Cleaning
31         std::fill_n(expected_first, n, trash);
32         std::fill_n(out_first, n, trash);
33 
34         // Run copy_if
35         auto i = std::remove_copy(first, last, expected_first, value);
36         (void)i;
37         auto k = std::remove_copy(exec, first, last, out_first, value);
38         EXPECT_EQ_N(expected_first, out_first, n, "wrong remove_copy effect");
39         for (size_t j = 0; j < GuardSize; ++j)
40         {
41             ++k;
42         }
43         EXPECT_TRUE(out_last == k, "wrong return value from remove_copy");
44     }
45 };
46 
47 template <typename T, typename Convert>
48 void
49 test(T trash, const T& value, Convert convert, bool check_weakness = true)
50 {
51     // Try sequences of various lengths.
52     for (size_t n = 0; n <= 100000; n = n <= 16 ? n + 1 : size_t(3.1415 * n))
53     {
54         // count is number of output elements, plus a handful
55         // more for sake of detecting buffer overruns.
56         size_t count = GuardSize;
57         Sequence<T> in(n, [&](size_t k) -> T {
58             T x = convert(n ^ k);
59             count += !(x == value) ? 1 : 0;
60             return x;
61         });
62         using namespace std;
63 
64         Sequence<T> out(count, [=](size_t) { return trash; });
65         Sequence<T> expected(count, [=](size_t) { return trash; });
66         if (check_weakness)
67         {
68             auto expected_result = remove_copy(in.cfbegin(), in.cfend(), expected.begin(), value);
69             size_t m = expected_result - expected.begin();
70             EXPECT_TRUE(n / 4 <= m && m <= 3 * (n + 1) / 4, "weak test for remove_copy");
71         }
72         invoke_on_all_policies(run_remove_copy(), in.begin(), in.end(), out.begin(), out.end(), expected.begin(),
73                                expected.end(), count, value, trash);
74         invoke_on_all_policies(run_remove_copy(), in.cbegin(), in.cend(), out.begin(), out.end(), expected.begin(),
75                                expected.end(), count, value, trash);
76     }
77 }
78 
79 int
80 main()
81 {
82 
83     test<float64_t>(-666.0, 8.5, [](size_t j) { return ((j + 1) % 7 & 2) != 0 ? 8.5 : float64_t(j % 32 + j); });
84 
85     test<int32_t>(-666, 42, [](size_t j) { return ((j + 1) % 5 & 2) != 0 ? 42 : -1 - int32_t(j); });
86 
87     test<Number>(Number(42, OddTag()), Number(2001, OddTag()),
88                  [](int32_t j) { return ((j + 1) % 3 & 2) != 0 ? Number(2001, OddTag()) : Number(j, OddTag()); });
89     std::cout << done() << std::endl;
90     return 0;
91 }
92