[libcxx-commits] [libcxx] r366776 - Implement most of P1612R1: Relocate endian. Moves the std::endian functionality from 'type-traits' to 'bit'. No other change. The reason that this is 'partial' is that P1621 also recommends a feature-test macro, but I don't have the value for that one yet. In a month or so, I'll add that
Marshall Clow via libcxx-commits
libcxx-commits at lists.llvm.org
Mon Jul 22 21:20:19 PDT 2019
Author: marshall
Date: Mon Jul 22 21:20:19 2019
New Revision: 366776
URL: http://llvm.org/viewvc/llvm-project?rev=366776&view=rev
Log:
Implement most of P1612R1: Relocate endian. Moves the std::endian functionality from 'type-traits' to 'bit'. No other change. The reason that this is 'partial' is that P1621 also recommends a feature-test macro, but I don't have the value for that one yet. In a month or so, I'll add that
Added:
libcxx/trunk/test/std/numerics/bit/bit.endian/
libcxx/trunk/test/std/numerics/bit/bit.endian/endian.pass.cpp
Removed:
libcxx/trunk/test/std/utilities/meta/meta.type.synop/endian.pass.cpp
Modified:
libcxx/trunk/include/bit
libcxx/trunk/include/type_traits
Modified: libcxx/trunk/include/bit
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/bit?rev=366776&r1=366775&r2=366776&view=diff
==============================================================================
--- libcxx/trunk/include/bit (original)
+++ libcxx/trunk/include/bit Mon Jul 22 21:20:19 2019
@@ -42,6 +42,13 @@ namespace std {
template<class T>
constexpr int popcount(T x) noexcept; // C++20
+ // 20.15.9, endian
+ enum class endian {
+ little = see below, // C++20
+ big = see below, // C++20
+ native = see below // C++20
+};
+
} // namespace std
*/
@@ -456,6 +463,20 @@ log2p1(_Tp __t) noexcept
return __t == 0 ? 0 : __bit_log2(__t) + 1;
}
+
+enum class endian
+{
+ little = 0xDEAD,
+ big = 0xFACE,
+#if defined(_LIBCPP_LITTLE_ENDIAN)
+ native = little
+#elif defined(_LIBCPP_BIG_ENDIAN)
+ native = big
+#else
+ native = 0xCAFE
+#endif
+};
+
#endif // _LIBCPP_STD_VER > 17
_LIBCPP_END_NAMESPACE_STD
Modified: libcxx/trunk/include/type_traits
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/type_traits?rev=366776&r1=366775&r2=366776&view=diff
==============================================================================
--- libcxx/trunk/include/type_traits (original)
+++ libcxx/trunk/include/type_traits Mon Jul 22 21:20:19 2019
@@ -3985,21 +3985,6 @@ struct __can_extract_map_key<_ValTy, _Ke
#endif
-#if _LIBCPP_STD_VER > 17
-enum class endian
-{
- little = 0xDEAD,
- big = 0xFACE,
-#if defined(_LIBCPP_LITTLE_ENDIAN)
- native = little
-#elif defined(_LIBCPP_BIG_ENDIAN)
- native = big
-#else
- native = 0xCAFE
-#endif
-};
-#endif
-
#ifndef _LIBCPP_HAS_NO_BUILTIN_IS_CONSTANT_EVALUATED
#if _LIBCPP_STD_VER > 17
_LIBCPP_INLINE_VISIBILITY
Added: libcxx/trunk/test/std/numerics/bit/bit.endian/endian.pass.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/std/numerics/bit/bit.endian/endian.pass.cpp?rev=366776&view=auto
==============================================================================
--- libcxx/trunk/test/std/numerics/bit/bit.endian/endian.pass.cpp (added)
+++ libcxx/trunk/test/std/numerics/bit/bit.endian/endian.pass.cpp Mon Jul 22 21:20:19 2019
@@ -0,0 +1,49 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
+
+// enum class endian;
+// <bit>
+
+#include <bit>
+#include <cstring>
+#include <cassert>
+#include <cstdint>
+
+#include "test_macros.h"
+
+int main(int, char**) {
+ static_assert(std::is_enum<std::endian>::value, "");
+
+// Check that E is a scoped enum by checking for conversions.
+ typedef std::underlying_type<std::endian>::type UT;
+ static_assert(!std::is_convertible<std::endian, UT>::value, "");
+
+// test that the enumeration values exist
+ static_assert( std::endian::little == std::endian::little );
+ static_assert( std::endian::big == std::endian::big );
+ static_assert( std::endian::native == std::endian::native );
+ static_assert( std::endian::little != std::endian::big );
+
+// Technically not required, but true on all existing machines
+ static_assert( std::endian::native == std::endian::little ||
+ std::endian::native == std::endian::big );
+
+// Try to check at runtime
+ {
+ uint32_t i = 0x01020304;
+ char c[4];
+ static_assert(sizeof(i) == sizeof(c));
+ std::memcpy(c, &i, sizeof(c));
+
+ assert ((c[0] == 1) == (std::endian::native == std::endian::big));
+ }
+
+ return 0;
+}
Removed: libcxx/trunk/test/std/utilities/meta/meta.type.synop/endian.pass.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/std/utilities/meta/meta.type.synop/endian.pass.cpp?rev=366775&view=auto
==============================================================================
--- libcxx/trunk/test/std/utilities/meta/meta.type.synop/endian.pass.cpp (original)
+++ libcxx/trunk/test/std/utilities/meta/meta.type.synop/endian.pass.cpp (removed)
@@ -1,48 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
-
-// enum class endian;
-
-#include <type_traits>
-#include <cstring>
-#include <cassert>
-#include <cstdint>
-
-#include "test_macros.h"
-
-int main(int, char**) {
- static_assert(std::is_enum<std::endian>::value, "");
-
-// Check that E is a scoped enum by checking for conversions.
- typedef std::underlying_type<std::endian>::type UT;
- static_assert(!std::is_convertible<std::endian, UT>::value, "");
-
-// test that the enumeration values exist
- static_assert( std::endian::little == std::endian::little );
- static_assert( std::endian::big == std::endian::big );
- static_assert( std::endian::native == std::endian::native );
- static_assert( std::endian::little != std::endian::big );
-
-// Technically not required, but true on all existing machines
- static_assert( std::endian::native == std::endian::little ||
- std::endian::native == std::endian::big );
-
-// Try to check at runtime
- {
- uint32_t i = 0x01020304;
- char c[4];
- static_assert(sizeof(i) == sizeof(c));
- std::memcpy(c, &i, sizeof(c));
-
- assert ((c[0] == 1) == (std::endian::native == std::endian::big));
- }
-
- return 0;
-}
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