commit 91bebaac72e6b076c959a118215d0c31c27b45e4
author Marek Kurdej <marek@quasardb.net> Tue Nov 24 21:07:06 2020 +0100
committer Copybara-Service <copybara-worker@google.com> Tue Nov 24 12:11:11 2020 -0800
tree 6ab4505cd6bb3c9bf9523048c49b32bedb90e4ae
parent 5b20ae95da1f6a0aa6c79430f31d8f15b4526ba8

[libc++] [P0482] [C++20] Implement missing bits for atomic

Added: ATOMIC_CHAR8_T_LOCK_FREE, atomic<char8_t>, atomic_char8_t.
http://wg21.link/P0482

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D91706

GitOrigin-RevId: 9c97e4ef4529ee2b518af6c1f2f68d2634946b3a

include/atomic

diff --git a/include/atomic b/include/atomic
index 70f1769..2652256 100644
--- a/include/atomic
+++ b/include/atomic
@@ -48,6 +48,7 @@
 
 #define ATOMIC_BOOL_LOCK_FREE unspecified
 #define ATOMIC_CHAR_LOCK_FREE unspecified
+#define ATOMIC_CHAR8_T_LOCK_FREE unspecified // C++20
 #define ATOMIC_CHAR16_T_LOCK_FREE unspecified
 #define ATOMIC_CHAR32_T_LOCK_FREE unspecified
 #define ATOMIC_WCHAR_T_LOCK_FREE unspecified
@@ -465,6 +466,7 @@
 typedef atomic<unsigned long>      atomic_ulong;
 typedef atomic<long long>          atomic_llong;
 typedef atomic<unsigned long long> atomic_ullong;
+typedef atomic<char8_t>            atomic_char8_t; // C++20
 typedef atomic<char16_t>           atomic_char16_t;
 typedef atomic<char32_t>           atomic_char32_t;
 typedef atomic<wchar_t>            atomic_wchar_t;
@@ -1125,6 +1127,9 @@
 #if defined(__CLANG_ATOMIC_BOOL_LOCK_FREE)
 # define ATOMIC_BOOL_LOCK_FREE      __CLANG_ATOMIC_BOOL_LOCK_FREE
 # define ATOMIC_CHAR_LOCK_FREE      __CLANG_ATOMIC_CHAR_LOCK_FREE
+#ifndef _LIBCPP_NO_HAS_CHAR8_T
+# define ATOMIC_CHAR8_T_LOCK_FREE   __CLANG_ATOMIC_CHAR8_T_LOCK_FREE
+#endif
 # define ATOMIC_CHAR16_T_LOCK_FREE  __CLANG_ATOMIC_CHAR16_T_LOCK_FREE
 # define ATOMIC_CHAR32_T_LOCK_FREE  __CLANG_ATOMIC_CHAR32_T_LOCK_FREE
 # define ATOMIC_WCHAR_T_LOCK_FREE   __CLANG_ATOMIC_WCHAR_T_LOCK_FREE
@@ -1136,6 +1141,9 @@
 #elif defined(__GCC_ATOMIC_BOOL_LOCK_FREE)
 # define ATOMIC_BOOL_LOCK_FREE      __GCC_ATOMIC_BOOL_LOCK_FREE
 # define ATOMIC_CHAR_LOCK_FREE      __GCC_ATOMIC_CHAR_LOCK_FREE
+#ifndef _LIBCPP_NO_HAS_CHAR8_T
+# define ATOMIC_CHAR8_T_LOCK_FREE   __GCC_ATOMIC_CHAR8_T_LOCK_FREE
+#endif
 # define ATOMIC_CHAR16_T_LOCK_FREE  __GCC_ATOMIC_CHAR16_T_LOCK_FREE
 # define ATOMIC_CHAR32_T_LOCK_FREE  __GCC_ATOMIC_CHAR32_T_LOCK_FREE
 # define ATOMIC_WCHAR_T_LOCK_FREE   __GCC_ATOMIC_WCHAR_T_LOCK_FREE
@@ -1450,6 +1458,9 @@
 template<> struct __cxx_is_always_lock_free<char> { enum { __value = 2 == ATOMIC_CHAR_LOCK_FREE }; };
 template<> struct __cxx_is_always_lock_free<signed char> { enum { __value = 2 == ATOMIC_CHAR_LOCK_FREE }; };
 template<> struct __cxx_is_always_lock_free<unsigned char> { enum { __value = 2 == ATOMIC_CHAR_LOCK_FREE }; };
+#ifndef _LIBCPP_NO_HAS_CHAR8_T
+template<> struct __cxx_is_always_lock_free<char8_t> { enum { __value = 2 == ATOMIC_CHAR8_T_LOCK_FREE }; };
+#endif
 template<> struct __cxx_is_always_lock_free<char16_t> { enum { __value = 2 == ATOMIC_CHAR16_T_LOCK_FREE }; };
 template<> struct __cxx_is_always_lock_free<char32_t> { enum { __value = 2 == ATOMIC_CHAR32_T_LOCK_FREE }; };
 template<> struct __cxx_is_always_lock_free<wchar_t> { enum { __value = 2 == ATOMIC_WCHAR_T_LOCK_FREE }; };
@@ -2721,6 +2732,9 @@
 typedef atomic<unsigned long>      atomic_ulong;
 typedef atomic<long long>          atomic_llong;
 typedef atomic<unsigned long long> atomic_ullong;
+#ifndef _LIBCPP_NO_HAS_CHAR8_T
+typedef atomic<char8_t>            atomic_char8_t;
+#endif
 typedef atomic<char16_t>           atomic_char16_t;
 typedef atomic<char32_t>           atomic_char32_t;
 typedef atomic<wchar_t>            atomic_wchar_t;