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Fix string_view construction from std::string_view (NVIDIA#6291) (NVIDIA#6301)
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3 files changed

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-10
lines changed

3 files changed

+141
-10
lines changed

‎libcudacxx/include/cuda/std/__fwd/char_traits.h‎

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@@ -42,6 +42,11 @@ template <>
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struct char_traits<wchar_t>;
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#endif // _CCCL_HAS_WCHAR_T()
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template <class _Tp>
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inline constexpr bool __is_cuda_std_char_traits_v = false;
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template <class _Tp>
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inline constexpr bool __is_cuda_std_char_traits_v<char_traits<_Tp>> = true;
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_LIBCUDACXX_END_NAMESPACE_STD
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#include <cuda/std/__cccl/epilogue.h>

‎libcudacxx/include/cuda/std/string_view‎

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Original file line numberDiff line numberDiff line change
@@ -84,6 +84,13 @@ template <class _CharT, class _Traits, class _Alloc>
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inline constexpr bool __cccl_is_std_string_v<::std::basic_string<_CharT, _Traits, _Alloc>> = true;
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#endif // !_CCCL_COMPILER(NVRTC)
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template <class _Tp>
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inline constexpr bool __is_std_char_traits_v = false;
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#if !_CCCL_COMPILER(NVRTC)
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template <class _Tp>
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inline constexpr bool __is_std_char_traits_v<::std::char_traits<_Tp>> = true;
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#endif // !_CCCL_COMPILER(NVRTC)
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template <class _Tp>
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inline constexpr bool __cccl_is_std_string_view_v = false;
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#if __cpp_lib_string_view >= 201606L
@@ -134,6 +141,13 @@ _CCCL_CONCEPT __cccl_basic_sv_compatible_range = _CCCL_REQUIRES_EXPR((_Range, _C
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|| __cccl_basic_sv_compatible_range_check_traits_std_ext<_Range, _CharT, _Traits>) )) //
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);
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template <class _Traits, class _HostTraits>
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_CCCL_CONCEPT __cccl_basic_sv_is_std_to_cuda_std_char_traits = _CCCL_REQUIRES_EXPR((_Traits, _HostTraits)) //
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( //
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requires(__is_cuda_std_char_traits_v<_Traits>), //
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requires(__is_std_char_traits_v<_HostTraits>) //
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);
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template <class _CharT, class _Traits>
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class _CCCL_TYPE_VISIBILITY_DEFAULT basic_string_view
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{
@@ -201,30 +215,32 @@ public:
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}
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#if !_CCCL_COMPILER(NVRTC)
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_CCCL_TEMPLATE(class _Traits2 = _Traits, class _Alloc)
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_CCCL_REQUIRES(is_same_v<_Traits2, char_traits<_CharT>>)
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_CCCL_HOST_API constexpr basic_string_view(
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const ::std::basic_string<_CharT, ::std::char_traits<_CharT>, _Alloc>& __sv) noexcept
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_CCCL_TEMPLATE(class _Traits2, class _Alloc)
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_CCCL_REQUIRES(__cccl_basic_sv_is_std_to_cuda_std_char_traits<_Traits, _Traits2>)
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_CCCL_HOST_API constexpr basic_string_view(const ::std::basic_string<_CharT, _Traits2, _Alloc>& __sv) noexcept
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: __data_{__sv.data()}
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, __size_{__sv.size()}
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{}
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template <class _Alloc>
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_CCCL_HOST_API constexpr basic_string_view(const ::std::basic_string<_CharT, _Traits, _Alloc>& __sv) noexcept
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_CCCL_TEMPLATE(class _Traits2, class _Alloc)
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_CCCL_REQUIRES(is_same_v<_Traits, _Traits2>)
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_CCCL_HOST_API constexpr basic_string_view(const ::std::basic_string<_CharT, _Traits2, _Alloc>& __sv) noexcept
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: __data_{__sv.data()}
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, __size_{__sv.size()}
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{}
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#endif // !_CCCL_COMPILER(NVRTC)
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#if __cpp_lib_string_view >= 201606L
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_CCCL_TEMPLATE(class _Traits2 = _Traits)
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_CCCL_REQUIRES(is_same_v<_Traits2, char_traits<_CharT>>)
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_CCCL_HOST_API constexpr basic_string_view(::std::basic_string_view<_CharT> __s) noexcept
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_CCCL_TEMPLATE(class _Traits2)
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_CCCL_REQUIRES(__cccl_basic_sv_is_std_to_cuda_std_char_traits<_Traits, _Traits2>)
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_CCCL_HOST_API constexpr basic_string_view(const ::std::basic_string_view<_CharT, _Traits2>& __s) noexcept
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: __data_{__s.data()}
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, __size_{__s.size()}
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{}
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_CCCL_HOST_API constexpr basic_string_view(::std::basic_string_view<_CharT, _Traits> __s) noexcept
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_CCCL_TEMPLATE(class _Traits2)
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_CCCL_REQUIRES(is_same_v<_Traits, _Traits2>)
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_CCCL_HOST_API constexpr basic_string_view(const ::std::basic_string_view<_CharT, _Traits2>& __s) noexcept
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: __data_{__s.data()}
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, __size_{__s.size()}
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{}

‎libcudacxx/test/libcudacxx/cuda/strings/std_interop/deleted_std_char_traits.compile.pass.cpp‎

Lines changed: 110 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,110 @@
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//===----------------------------------------------------------------------===//
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//
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// Part of the libcu++ 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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// SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES.
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//
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//===----------------------------------------------------------------------===//
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// <cuda/std/string_view>
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// UNSUPPORTED: nvrtc
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#include <cuda/std/cassert>
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#include <cuda/std/string_view>
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#include <cuda/std/type_traits>
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#include <string>
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#include "literal.h"
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enum class MyChar : char
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{
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};
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template <>
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struct std::char_traits<MyChar>
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{};
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template <>
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struct cuda::std::char_traits<MyChar>
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{
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using base = cuda::std::char_traits<char>;
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using char_type = MyChar;
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using int_type = typename base::int_type;
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__host__ __device__ static constexpr void assign(char_type& __lhs, const char_type& __rhs) noexcept
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{
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__lhs = __rhs;
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}
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[[nodiscard]] __host__ __device__ static constexpr bool eq(char_type __lhs, char_type __rhs) noexcept
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{
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return __lhs == __rhs;
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}
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[[nodiscard]] __host__ __device__ static constexpr bool lt(char_type __lhs, char_type __rhs) noexcept
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{
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return static_cast<unsigned char>(__lhs) < static_cast<unsigned char>(__rhs);
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}
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[[nodiscard]] __host__ __device__ static constexpr int
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compare(const char_type* __lhs, const char_type* __rhs, size_t __count) noexcept
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{
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return ::cuda::std::__cccl_memcmp(__lhs, __rhs, __count);
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}
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[[nodiscard]] __host__ __device__ inline static size_t constexpr length(const char_type* __s) noexcept
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{
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return ::cuda::std::__cccl_strlen(__s);
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}
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[[nodiscard]] __host__ __device__ static constexpr const char_type*
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find(const char_type* __s, size_t __n, const char_type& __a) noexcept
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{
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return ::cuda::std::__cccl_memchr<const char_type>(__s, __a, __n);
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}
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__host__ __device__ static constexpr char_type* move(char_type* __s1, const char_type* __s2, size_t __n) noexcept
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{
72+
return ::cuda::std::__cccl_memmove(__s1, __s2, __n);
73+
}
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75+
__host__ __device__ static constexpr char_type* copy(char_type* __s1, const char_type* __s2, size_t __n) noexcept
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{
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return ::cuda::std::__cccl_memcpy(__s1, __s2, __n);
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}
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__host__ __device__ static constexpr char_type* assign(char_type* __s, size_t __n, char_type __a) noexcept
81+
{
82+
return ::cuda::std::__cccl_memset(__s, __a, __n);
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}
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[[nodiscard]] __host__ __device__ static constexpr char_type to_char_type(int_type __c) noexcept
86+
{
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return char_type(__c);
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}
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[[nodiscard]] __host__ __device__ static constexpr int_type to_int_type(char_type __c) noexcept
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{
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return int_type(static_cast<unsigned char>(__c));
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}
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[[nodiscard]] __host__ __device__ static constexpr bool eq_int_type(int_type __lhs, int_type __rhs) noexcept
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{
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return __lhs == __rhs;
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}
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};
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bool test()
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{
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[[maybe_unused]] cuda::std::basic_string_view<MyChar> str{reinterpret_cast<const MyChar*>("test")};
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return true;
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}
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int main(int, char**)
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{
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return 0;
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}

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