1 files changed, 94 insertions, 0 deletions
diff --git a/contrib/llvm-project/libcxx/include/__random/is_valid.h b/contrib/llvm-project/libcxx/include/__random/is_valid.h
new file mode 100644
index 000000000000..a3e0f143ae86
--- /dev/null
+++ b/contrib/llvm-project/libcxx/include/__random/is_valid.h
@@ -0,0 +1,94 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___RANDOM_IS_VALID_H
+#define _LIBCPP___RANDOM_IS_VALID_H
+
+#include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_unsigned.h>
+#include <__utility/declval.h>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// [rand.req.genl]/1.4:
+// The effect of instantiating a template that has a template type parameter
+// named RealType is undefined unless the corresponding template argument is
+// cv-unqualified and is one of float, double, or long double.
+
+template <class>
+struct __libcpp_random_is_valid_realtype : false_type {};
+template <>
+struct __libcpp_random_is_valid_realtype<float> : true_type {};
+template <>
+struct __libcpp_random_is_valid_realtype<double> : true_type {};
+template <>
+struct __libcpp_random_is_valid_realtype<long double> : true_type {};
+
+// [rand.req.genl]/1.5:
+// The effect of instantiating a template that has a template type parameter
+// named IntType is undefined unless the corresponding template argument is
+// cv-unqualified and is one of short, int, long, long long, unsigned short,
+// unsigned int, unsigned long, or unsigned long long.
+
+template <class>
+struct __libcpp_random_is_valid_inttype : false_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<int8_t> : true_type {}; // extension
+template <>
+struct __libcpp_random_is_valid_inttype<short> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<int> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<long> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<long long> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<uint8_t> : true_type {}; // extension
+template <>
+struct __libcpp_random_is_valid_inttype<unsigned short> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<unsigned int> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<unsigned long> : true_type {};
+template <>
+struct __libcpp_random_is_valid_inttype<unsigned long long> : true_type {};
+
+#ifndef _LIBCPP_HAS_NO_INT128
+template <>
+struct __libcpp_random_is_valid_inttype<__int128_t> : true_type {}; // extension
+template <>
+struct __libcpp_random_is_valid_inttype<__uint128_t> : true_type {}; // extension
+#endif                                                               // _LIBCPP_HAS_NO_INT128
+
+// [rand.req.urng]/3:
+// A class G meets the uniform random bit generator requirements if G models
+// uniform_random_bit_generator, invoke_result_t<G&> is an unsigned integer type,
+// and G provides a nested typedef-name result_type that denotes the same type
+// as invoke_result_t<G&>.
+// (In particular, reject URNGs with signed result_types; our distributions cannot
+// handle such generator types.)
+
+template <class, class = void>
+struct __libcpp_random_is_valid_urng : false_type {};
+template <class _Gp>
+struct __libcpp_random_is_valid_urng<
+    _Gp,
+    __enable_if_t< is_unsigned<typename _Gp::result_type>::value &&
+                   _IsSame<decltype(std::declval<_Gp&>()()), typename _Gp::result_type>::value > > : true_type {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___RANDOM_IS_VALID_H