libcxx/test/std/numerics/numeric.ops/numeric.ops.midpoint/midpoint.pointer.pass.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-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // UNSUPPORTED: c++03, c++11, c++14, c++17
  10 // <numeric>
  11
  12 // template <class _Tp>
  13 // _Tp* midpoint(_Tp* __a, _Tp* __b) noexcept
  14 //
  15
  16 #include <numeric>
  17 #include <cassert>
  18
  19 #include "test_macros.h"
  20
  21
  22
  23 template <typename T>
  24 constexpr void constexpr_test()
  25 {
  26     constexpr T array[1000] = {};
  27     ASSERT_SAME_TYPE(decltype(std::midpoint(array, array)), const T*);
  28     ASSERT_NOEXCEPT(          std::midpoint(array, array));
  29
  30     static_assert(std::midpoint(array, array)        == array, "");
  31     static_assert(std::midpoint(array, array + 1000) == array + 500, "");
  32
  33     static_assert(std::midpoint(array, array +    9) == array + 4, "");
  34     static_assert(std::midpoint(array, array +   10) == array + 5, "");
  35     static_assert(std::midpoint(array, array +   11) == array + 5, "");
  36     static_assert(std::midpoint(array +    9, array) == array + 5, "");
  37     static_assert(std::midpoint(array +   10, array) == array + 5, "");
  38     static_assert(std::midpoint(array +   11, array) == array + 6, "");
  39 }
  40
  41 template <typename T>
  42 void runtime_test()
  43 {
  44     T array[1000] = {}; // we need an array to make valid pointers
  45     ASSERT_SAME_TYPE(decltype(std::midpoint(array, array)), T*);
  46     ASSERT_NOEXCEPT(          std::midpoint(array, array));
  47
  48     assert(std::midpoint(array, array)        == array);
  49     assert(std::midpoint(array, array + 1000) == array + 500);
  50
  51     assert(std::midpoint(array, array +    9) == array + 4);
  52     assert(std::midpoint(array, array +   10) == array + 5);
  53     assert(std::midpoint(array, array +   11) == array + 5);
  54     assert(std::midpoint(array +    9, array) == array + 5);
  55     assert(std::midpoint(array +   10, array) == array + 5);
  56     assert(std::midpoint(array +   11, array) == array + 6);
  57
  58     // explicit instantiation
  59     ASSERT_SAME_TYPE(decltype(std::midpoint<T>(array, array)), T*);
  60     ASSERT_NOEXCEPT(std::midpoint<T>(array, array));
  61     assert(std::midpoint<T>(array, array) == array);
  62     assert(std::midpoint<T>(array, array + 1000) == array + 500);
  63 }
  64
  65 template <typename T>
  66 void pointer_test()
  67 {
  68     runtime_test<               T>();
  69     runtime_test<const          T>();
  70     runtime_test<      volatile T>();
  71     runtime_test<const volatile T>();
  72
  73 //  The constexpr tests are always const, but we can test them anyway.
  74     constexpr_test<               T>();
  75     constexpr_test<const          T>();
  76
  77 //  GCC 9.0.1 (unreleased as of 2019-03) barfs on this, but we have a bot for it.
  78 //  Uncomment when gcc 9.1 is released
  79 #ifndef TEST_COMPILER_GCC
  80     constexpr_test<      volatile T>();
  81     constexpr_test<const volatile T>();
  82 #endif
  83 }
  84
  85
  86 int main(int, char**)
  87 {
  88     pointer_test<char>();
  89     pointer_test<int>();
  90     pointer_test<double>();
  91
  92     return 0;
  93 }