forked from OSchip/llvm-project
				
			
		
			
				
	
	
		
			117 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			117 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			C++
		
	
	
	
| // -*- C++ -*-
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| //===------------------------------ span ---------------------------------===//
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| //
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| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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| // See https://llvm.org/LICENSE.txt for license information.
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| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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| //
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| //===---------------------------------------------------------------------===//
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| // UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
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| 
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| // <span>
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| 
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| // template<size_t N>
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| //     constexpr span(array<value_type, N>& arr) noexcept;
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| // template<size_t N>
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| //     constexpr span(const array<value_type, N>& arr) noexcept;
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| //
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| // Remarks: These constructors shall not participate in overload resolution unless:
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| //   — extent == dynamic_extent || N == extent is true, and
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| //   — remove_pointer_t<decltype(data(arr))>(*)[] is convertible to ElementType(*)[].
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| //
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| 
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| 
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| #include <span>
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| #include <array>
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| #include <cassert>
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| #include <string>
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| 
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| #include "test_macros.h"
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| // std::array is explicitly allowed to be initialized with A a = { init-list };.
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| // Disable the missing braces warning for this reason.
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| #include "disable_missing_braces_warning.h"
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| 
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| 
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| void checkCV()
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| {
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|     std::array<int, 3> arr  = {1,2,3};
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| //  STL says these are not cromulent
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| //  std::array<const int,3> carr = {4,5,6};
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| //  std::array<volatile int, 3> varr = {7,8,9};
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| //  std::array<const volatile int, 3> cvarr = {1,3,5};
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| 
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| //  Types the same (dynamic sized)
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|     {
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|     std::span<               int> s1{  arr};    // a span<               int> pointing at int.
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|     }
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| 
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| //  Types the same (static sized)
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|     {
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|     std::span<               int,3> s1{  arr};  // a span<               int> pointing at int.
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|     }
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| 
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| 
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| //  types different (dynamic sized)
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|     {
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|     std::span<const          int> s1{ arr};     // a span<const          int> pointing at int.
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|     std::span<      volatile int> s2{ arr};     // a span<      volatile int> pointing at int.
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|     std::span<      volatile int> s3{ arr};     // a span<      volatile int> pointing at const int.
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|     std::span<const volatile int> s4{ arr};     // a span<const volatile int> pointing at int.
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|     }
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| 
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| //  types different (static sized)
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|     {
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|     std::span<const          int,3> s1{ arr};   // a span<const          int> pointing at int.
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|     std::span<      volatile int,3> s2{ arr};   // a span<      volatile int> pointing at int.
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|     std::span<      volatile int,3> s3{ arr};   // a span<      volatile int> pointing at const int.
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|     std::span<const volatile int,3> s4{ arr};   // a span<const volatile int> pointing at int.
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|     }
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| }
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| 
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| 
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| template <typename T>
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| constexpr bool testConstexprSpan()
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| {
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|     constexpr std::array<T,2> val = { T(), T() };
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|     ASSERT_NOEXCEPT(std::span<const T>   {val});
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|     ASSERT_NOEXCEPT(std::span<const T, 2>{val});
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|     std::span<const T>    s1{val};
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|     std::span<const T, 2> s2{val};
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|     return
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|         s1.data() == &val[0] && s1.size() == 2
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|     &&  s2.data() == &val[0] && s2.size() == 2;
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| }
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| 
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| 
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| template <typename T>
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| void testRuntimeSpan()
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| {
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|     std::array<T,2> val;
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|     ASSERT_NOEXCEPT(std::span<T>   {val});
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|     ASSERT_NOEXCEPT(std::span<T, 2>{val});
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|     std::span<T>    s1{val};
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|     std::span<T, 2> s2{val};
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|     assert(s1.data() == &val[0] && s1.size() == 2);
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|     assert(s2.data() == &val[0] && s2.size() == 2);
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| }
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| 
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| struct A{};
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| 
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| int main(int, char**)
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| {
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|     static_assert(testConstexprSpan<int>(),    "");
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|     static_assert(testConstexprSpan<long>(),   "");
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|     static_assert(testConstexprSpan<double>(), "");
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|     static_assert(testConstexprSpan<A>(),      "");
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| 
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|     testRuntimeSpan<int>();
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|     testRuntimeSpan<long>();
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|     testRuntimeSpan<double>();
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|     testRuntimeSpan<std::string>();
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|     testRuntimeSpan<A>();
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| 
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|     checkCV();
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| 
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|   return 0;
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| }
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