Implement P1023: constexpr comparison operators for std::array

llvm-svn: 338668

diff --git a/libcxx/include/array b/libcxx/include/array
index 1e6a650..ba4ff42 100644 (file)
--- a/libcxx/include/array
+++ b/libcxx/include/array
@@ -367,7 +367,7 @@ array(_Tp, _Args...)
 
 template <class _Tp, size_t _Size>
 inline _LIBCPP_INLINE_VISIBILITY
-bool
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
 operator==(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
 {
     return _VSTD::equal(__x.begin(), __x.end(), __y.begin());
@@ -375,7 +375,7 @@ operator==(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
 
 template <class _Tp, size_t _Size>
 inline _LIBCPP_INLINE_VISIBILITY
-bool
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
 operator!=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
 {
     return !(__x == __y);
@@ -383,7 +383,7 @@ operator!=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
 
 template <class _Tp, size_t _Size>
 inline _LIBCPP_INLINE_VISIBILITY
-bool
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
 operator<(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
 {
     return _VSTD::lexicographical_compare(__x.begin(), __x.end(),
@@ -392,7 +392,7 @@ operator<(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
 
 template <class _Tp, size_t _Size>
 inline _LIBCPP_INLINE_VISIBILITY
-bool
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
 operator>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
 {
     return __y < __x;
@@ -400,7 +400,7 @@ operator>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
 
 template <class _Tp, size_t _Size>
 inline _LIBCPP_INLINE_VISIBILITY
-bool
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
 operator<=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
 {
     return !(__y < __x);
@@ -408,7 +408,7 @@ operator<=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
 
 template <class _Tp, size_t _Size>
 inline _LIBCPP_INLINE_VISIBILITY
-bool
+_LIBCPP_CONSTEXPR_AFTER_CXX17 bool
 operator>=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
 {
     return !(__x < __y);

diff --git a/libcxx/test/std/containers/sequences/array/compare.pass.cpp b/libcxx/test/std/containers/sequences/array/compare.pass.cpp
index c8bcf75..f3e72b7 100644 (file)
--- a/libcxx/test/std/containers/sequences/array/compare.pass.cpp
+++ b/libcxx/test/std/containers/sequences/array/compare.pass.cpp
@@ -9,6 +9,7 @@
 
 // <array>
 
+//  These are all constexpr in C++20
 // bool operator==(array<T, N> const&, array<T, N> const&);
 // bool operator!=(array<T, N> const&, array<T, N> const&);
 // bool operator<(array<T, N> const&, array<T, N> const&);
@@ -40,6 +41,41 @@ void test_compare(const Array& LHS, const Array& RHS) {
   assert((LHS >= RHS) == (LHSV >= RHSV));
 }
 
+#if TEST_STD_VER > 17
+template <class Array>
+constexpr bool constexpr_compare(const Array &lhs, const Array &rhs, bool isEqual, bool isLess)
+{
+  if (isEqual)
+  {
+    if (!(lhs == rhs)) return false;
+    if ( (lhs != rhs)) return false;
+    if ( (lhs  < rhs)) return false;
+    if (!(lhs <= rhs)) return false;
+    if ( (lhs  > rhs)) return false;
+    if (!(lhs >= rhs)) return false;
+  }
+  else if (isLess)
+  {
+    if ( (lhs == rhs)) return false;
+    if (!(lhs != rhs)) return false;
+    if (!(lhs  < rhs)) return false;
+    if (!(lhs <= rhs)) return false;
+    if ( (lhs  > rhs)) return false;
+    if ( (lhs >= rhs)) return false;
+  }
+  else // greater
+  {
+    if ( (lhs == rhs)) return false;
+    if (!(lhs != rhs)) return false;
+    if ( (lhs  < rhs)) return false;
+    if ( (lhs <= rhs)) return false;
+    if (!(lhs  > rhs)) return false;
+    if (!(lhs >= rhs)) return false;
+  }
+  return true;  
+}
+#endif
+
 int main()
 {
   {
@@ -60,4 +96,14 @@ int main()
     C c2 = {};
     test_compare(c1, c2);
   }
+
+#if TEST_STD_VER > 17
+  {
+  constexpr std::array<int, 3> a1 = {1, 2, 3};
+  constexpr std::array<int, 3> a2 = {2, 3, 4};
+  static_assert(constexpr_compare(a1, a1, true, false), "");
+  static_assert(constexpr_compare(a1, a2, false, true), "");
+  static_assert(constexpr_compare(a2, a1, false, false), "");
+  }
+#endif
 }

diff --git a/libcxx/www/cxx2a_status.html b/libcxx/www/cxx2a_status.html
index fc69b29..fa6a47a 100644 (file)
--- a/libcxx/www/cxx2a_status.html
+++ b/libcxx/www/cxx2a_status.html
@@ -72,7 +72,7 @@
        <tr><td><a href="https://wg21.link/P0767R1">P0767R1</a></td><td>CWG</td><td>Deprecate POD</td><td>Albuquerque</td><td>Complete</td><td>7.0</td></tr>
        <tr><td><a href="https://wg21.link/P0768R1">P0768R1</a></td><td>CWG</td><td>Library Support for the Spaceship (Comparison) Operator</td><td>Albuquerque</td><td></td><td></td></tr>
        <tr><td><a href="https://wg21.link/P0777R1">P0777R1</a></td><td>LWG</td><td>Treating Unnecessary <tt>decay</tt></td><td>Albuquerque</td><td>Complete</td><td>7.0</td></tr>
-       <tr><td><a href="https://wg21.link/P0122R7">P0122R7</a></td><td>LWG</td><td>&lt;span&gt;</td><td>Jacksonville</td><td><i>Complete</i></td><td>7.0</td></tr>
+       <tr><td><a href="https://wg21.link/P0122R7">P0122R7</a></td><td>LWG</td><td>&lt;span&gt;</td><td>Jacksonville</td><td>Complete</td><td>7.0</td></tr>
        <tr><td><a href="https://wg21.link/P0355R7">P0355R7</a></td><td>LWG</td><td>Extending chrono to Calendars and Time Zones</td><td>Jacksonville</td><td></td><td></td></tr>
        <tr><td><a href="https://wg21.link/P0551R3">P0551R3</a></td><td>LWG</td><td>Thou Shalt Not Specialize <tt>std</tt> Function Templates!</td><td>Jacksonville</td><td></td><td></td></tr>
        <tr><td><a href="https://wg21.link/P0753R2">P0753R2</a></td><td>LWG</td><td>Manipulators for C++ Synchronized Buffered Ostream</td><td>Jacksonville</td><td></td><td></td></tr>
@@ -98,12 +98,12 @@
        <tr><td><a href="https://wg21.link/P0769R2">P0769R2</a></td><td>LWG</td><td>Add shift to &lt;algorithm&gt;</td><td>Rapperswil</td><td></td><td></td></tr>
        <tr><td><a href="https://wg21.link/P0788R3">P0788R3</a></td><td>LWG</td><td>Standard Library Specification in a Concepts and Contracts World</td><td>Rapperswil</td><td></td><td></td></tr>
        <tr><td><a href="https://wg21.link/P0879R0">P0879R0</a></td><td>LWG</td><td>Constexpr for swap and swap related functions Also resolves LWG issue 2800.</td><td>Rapperswil</td><td></td><td></td></tr>
-       <tr><td><a href="https://wg21.link/P0887R1">P0887R1</a></td><td>LWG</td><td>The identity metafunction</td><td>Rapperswil</td><td></td><td></td></tr>
+       <tr><td><a href="https://wg21.link/P0887R1">P0887R1</a></td><td>LWG</td><td>The identity metafunction</td><td>Rapperswil</td><td>Complete</td><td>8.0</td></tr>
        <tr><td><a href="https://wg21.link/P0892R2">P0892R2</a></td><td>CWG</td><td>explicit(bool)</td><td>Rapperswil</td><td></td><td></td></tr>
        <tr><td><a href="https://wg21.link/P0898R3">P0898R3</a></td><td>LWG</td><td>Standard Library Concepts</td><td>Rapperswil</td><td></td><td></td></tr>
        <tr><td><a href="https://wg21.link/P0935R0">P0935R0</a></td><td>LWG</td><td>Eradicating unnecessarily explicit default constructors from the standard library</td><td>Rapperswil</td><td></td><td></td></tr>
        <tr><td><a href="https://wg21.link/P0941R2">P0941R2</a></td><td>CWG</td><td>Integrating feature-test macros into the C++ WD</td><td>Rapperswil</td><td></td><td></td></tr>
-       <tr><td><a href="https://wg21.link/P1023R0">P1023R0</a></td><td>LWG</td><td>constexpr comparison operators for std::array</td><td>Rapperswil</td><td></td><td></td></tr>
+       <tr><td><a href="https://wg21.link/P1023R0">P1023R0</a></td><td>LWG</td><td>constexpr comparison operators for std::array</td><td>Rapperswil</td><td>Complete</td><td>8.0</td></tr>
        <tr><td><a href="https://wg21.link/P1025R1">P1025R1</a></td><td>CWG</td><td>Update The Reference To The Unicode Standard</td><td>Rapperswil</td><td></td><td></td></tr>
        <tr><td><a href="https://wg21.link/P1120R0">P1120R0</a></td><td>CWG</td><td>Consistency improvements for &lt;=&gt; and other comparison operators</td><td>Rapperswil</td><td></td><td></td></tr>
 
@@ -222,7 +222,7 @@
 <!--   <tr><td></td><td></td><td></td><td></td></tr> -->
   </table>
 
-  <p>Last Updated: 23-Jul-2018</p>
+  <p>Last Updated: 1-Aug-2018</p>
 </div>
 </body>
 </html>