1 // -*- C++ -*-
2 //===-- find.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 // Tests for find
11 #include "support/pstl_test_config.h"
12 
13 #include <execution>
14 #include <algorithm>
15 
16 #include "support/utils.h"
17 
18 using namespace TestUtils;
19 
20 struct test_find
21 {
22 #if _PSTL_ICC_17_VC141_TEST_SIMD_LAMBDA_DEBUG_32_BROKEN ||                                                            \
23     _PSTL_ICC_16_VC14_TEST_SIMD_LAMBDA_DEBUG_32_BROKEN //dummy specialization by policy type, in case of broken configuration
24     template <typename Iterator, typename Value>
25     void
26     operator()(pstl::execution::unsequenced_policy, Iterator first, Iterator last, Value value)
27     {
28     }
29     template <typename Iterator, typename Value>
30     void
31     operator()(pstl::execution::parallel_unsequenced_policy, Iterator first, Iterator last, Value value)
32     {
33     }
34 #endif
35 
36     template <typename Policy, typename Iterator, typename Value>
37     void
38     operator()(Policy&& exec, Iterator first, Iterator last, Value value)
39     {
40         auto i = std::find(first, last, value);
41         auto j = find(exec, first, last, value);
42         EXPECT_TRUE(i == j, "wrong return value from find");
43     }
44 };
45 
46 template <typename T, typename Value, typename Hit, typename Miss>
47 void
48 test(Value value, Hit hit, Miss miss)
49 {
50     // Try sequences of various lengths.
51     for (size_t n = 0; n <= 100000; n = n <= 16 ? n + 1 : size_t(3.1415 * n))
52     {
53         Sequence<T> in(n, [&](size_t k) -> T { return miss(n ^ k); });
54         // Try different find positions, including not found.
55         // By going backwards, we can add extra matches that are *not* supposed to be found.
56         // The decreasing exponential gives us O(n) total work for the loop since each find takes O(m) time.
57         for (size_t m = n; m > 0; m *= 0.6)
58         {
59             if (m < n)
60                 in[m] = hit(n ^ m);
61             invoke_on_all_policies(test_find(), in.begin(), in.end(), value);
62             invoke_on_all_policies(test_find(), in.cbegin(), in.cend(), value);
63         }
64     }
65 }
66 
67 // Type defined for sake of checking that std::find works with asymmetric ==.
68 class Weird
69 {
70     Number value;
71 
72   public:
73     friend bool
74     operator==(Number x, Weird y)
75     {
76         return x == y.value;
77     }
78     Weird(int32_t val, OddTag) : value(val, OddTag()) {}
79 };
80 
81 int32_t
82 main()
83 {
84     // Note that the "hit" and "miss" functions here avoid overflow issues.
85     test<Number>(Weird(42, OddTag()), [](int32_t j) { return Number(42, OddTag()); }, // hit
86                  [](int32_t j) { return Number(j == 42 ? 0 : j, OddTag()); });        // miss
87 
88     // Test with value that is equal to two different bit patterns (-0.0 and 0.0)
89     test<float32_t>(-0.0, [](int32_t j) { return j & 1 ? 0.0 : -0.0; }, // hit
90                     [](int32_t j) { return j == 0 ? ~j : j; });         // miss
91 
92     std::cout << done() << std::endl;
93     return 0;
94 }
95