[libcxx-commits] [libcxx] [libc++] Implement P2897R7 aligned_accessor: An mdspan accessor expressing pointer over-alignment (PR #122603)
Damien L-G via libcxx-commits
libcxx-commits at lists.llvm.org
Fri Jan 31 18:42:35 PST 2025
https://github.com/dalg24 updated https://github.com/llvm/llvm-project/pull/122603
>From 2766103a12489bcbfa75b3df0b6225a35e33543d Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Sat, 11 Jan 2025 13:22:17 -0500
Subject: [PATCH 01/13] [libc++] Implement P2897R7 aligned_accessor: An mdspan
accessor expressing pointer over-alignment
---
libcxx/docs/FeatureTestMacroTable.rst | 4 +
libcxx/docs/Status/Cxx2cPapers.csv | 2 +-
libcxx/include/CMakeLists.txt | 2 +
libcxx/include/__mdspan/aligned_accessor.h | 86 ++++++++++++++
libcxx/include/__mdspan/mdspan.h | 9 +-
.../__memory/is_sufficiently_aligned.h | 34 ++++++
libcxx/include/mdspan | 38 ++++++-
libcxx/include/memory | 4 +
libcxx/include/module.modulemap | 2 +
libcxx/modules/std/mdspan.inc | 5 +
libcxx/modules/std/memory.inc | 3 +
.../mdspan/aligned_accessor/access.pass.cpp | 61 ++++++++++
.../byte_alignment.verify.cpp | 29 +++++
....conversion.from.default_accessor.pass.cpp | 81 ++++++++++++++
.../aligned_accessor/ctor.conversion.pass.cpp | 104 +++++++++++++++++
.../aligned_accessor/ctor.default.pass.cpp | 56 ++++++++++
.../aligned_accessor/element_type.verify.cpp | 32 ++++++
.../mdspan/aligned_accessor/offset.pass.cpp | 61 ++++++++++
...or.conversion.to.default_accessor.pass.cpp | 80 +++++++++++++
.../mdspan/aligned_accessor/types.pass.cpp | 70 ++++++++++++
.../is_sufficiently_aligned.pass.cpp | 105 ++++++++++++++++++
21 files changed, 862 insertions(+), 6 deletions(-)
create mode 100644 libcxx/include/__mdspan/aligned_accessor.h
create mode 100644 libcxx/include/__memory/is_sufficiently_aligned.h
create mode 100644 libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp
create mode 100644 libcxx/test/std/containers/views/mdspan/aligned_accessor/byte_alignment.verify.cpp
create mode 100644 libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.from.default_accessor.pass.cpp
create mode 100644 libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.pass.cpp
create mode 100644 libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.default.pass.cpp
create mode 100644 libcxx/test/std/containers/views/mdspan/aligned_accessor/element_type.verify.cpp
create mode 100644 libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp
create mode 100644 libcxx/test/std/containers/views/mdspan/aligned_accessor/operator.conversion.to.default_accessor.pass.cpp
create mode 100644 libcxx/test/std/containers/views/mdspan/aligned_accessor/types.pass.cpp
create mode 100644 libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp
diff --git a/libcxx/docs/FeatureTestMacroTable.rst b/libcxx/docs/FeatureTestMacroTable.rst
index cfb0e5cfb129ce..ae8cbe61fd7d17 100644
--- a/libcxx/docs/FeatureTestMacroTable.rst
+++ b/libcxx/docs/FeatureTestMacroTable.rst
@@ -406,6 +406,8 @@ Status
----------------------------------------------------------------------------
``__cpp_lib_associative_heterogeneous_insertion`` *unimplemented*
---------------------------------------------------------- -----------------
+ ``__cpp_lib_aligned_accessor`` ``202411L``
+ ---------------------------------------------------------- -----------------
``__cpp_lib_atomic_min_max`` *unimplemented*
---------------------------------------------------------- -----------------
``__cpp_lib_bind_front`` ``202306L``
@@ -450,6 +452,8 @@ Status
---------------------------------------------------------- -----------------
``__cpp_lib_inplace_vector`` *unimplemented*
---------------------------------------------------------- -----------------
+ ``__cpp_lib_is_sufficiently_aligned`` ``202411L``
+ ---------------------------------------------------------- -----------------
``__cpp_lib_is_virtual_base_of`` ``202406L``
---------------------------------------------------------- -----------------
``__cpp_lib_is_within_lifetime`` *unimplemented*
diff --git a/libcxx/docs/Status/Cxx2cPapers.csv b/libcxx/docs/Status/Cxx2cPapers.csv
index aa896e85fcb1fe..ae1f887947fe06 100644
--- a/libcxx/docs/Status/Cxx2cPapers.csv
+++ b/libcxx/docs/Status/Cxx2cPapers.csv
@@ -81,7 +81,7 @@
"`P3379R0 <https://wg21.link/P3379R0>`__","Constrain ``std::expected`` equality operators","2024-11 (Wrocław)","","",""
"`P0472R2 <https://wg21.link/P0472R2>`__","Put ``std::monostate`` in ``<utility>``","2024-11 (Wrocław)","","",""
"`P2862R1 <https://wg21.link/P2862R1>`__","``text_encoding::name()`` should never return null values","2024-11 (Wrocław)","","",""
-"`P2897R7 <https://wg21.link/P2897R7>`__","``aligned_accessor``: An ``mdspan`` accessor expressing pointer over-alignment","2024-11 (Wrocław)","","",""
+"`P2897R7 <https://wg21.link/P2897R7>`__","``aligned_accessor``: An ``mdspan`` accessor expressing pointer over-alignment","2024-11 (Wrocław)","|Complete|","20",""
"`P3355R1 <https://wg21.link/P3355R1>`__","Fix ``submdspan`` for C++26","2024-11 (Wrocław)","","",""
"`P3222R0 <https://wg21.link/P3222R0>`__","Fix C++26 by adding transposed special cases for P2642 layouts","2024-11 (Wrocław)","","",""
"`P3050R2 <https://wg21.link/P3050R2>`__","Fix C++26 by optimizing ``linalg::conjugated`` for noncomplex value types","2024-11 (Wrocław)","","",""
diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index f7721b1047b81e..ad7574b8993d08 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -529,6 +529,7 @@ set(files
__math/traits.h
__math/trigonometric_functions.h
__mbstate_t.h
+ __mdspan/aligned_accessor.h
__mdspan/default_accessor.h
__mdspan/extents.h
__mdspan/layout_left.h
@@ -553,6 +554,7 @@ set(files
__memory/construct_at.h
__memory/destruct_n.h
__memory/inout_ptr.h
+ __memory/is_sufficiently_aligned.h
__memory/noexcept_move_assign_container.h
__memory/out_ptr.h
__memory/pointer_traits.h
diff --git a/libcxx/include/__mdspan/aligned_accessor.h b/libcxx/include/__mdspan/aligned_accessor.h
new file mode 100644
index 00000000000000..441c144c11aebb
--- /dev/null
+++ b/libcxx/include/__mdspan/aligned_accessor.h
@@ -0,0 +1,86 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+// Kokkos v. 4.0
+// Copyright (2022) National Technology & Engineering
+// Solutions of Sandia, LLC (NTESS).
+//
+// Under the terms of Contract DE-NA0003525 with NTESS,
+// the U.S. Government retains certain rights in this software.
+//
+//===---------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MDSPAN_ALIGNED_ACCESSOR_H
+#define _LIBCPP___MDSPAN_ALIGNED_ACCESSOR_H
+
+#include <__config>
+#include <__cstddef/size_t.h>
+#include <__memory/assume_aligned.h>
+#include <__type_traits/is_abstract.h>
+#include <__type_traits/is_array.h>
+#include <__type_traits/is_convertible.h>
+#include <__type_traits/remove_const.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 26
+
+template <class _ElementType, size_t _ByteAlignment>
+struct aligned_accessor {
+ static_assert(_ByteAlignment != 0 && (_ByteAlignment & (_ByteAlignment - 1)) == 0,
+ "aligned_accessor: byte alignment must be a power of two");
+ static_assert(_ByteAlignment >= alignof(_ElementType), "aligned_accessor: insufficient byte alignment");
+ static_assert(!is_array_v<_ElementType>, "aligned_accessor: template argument may not be an array type");
+ static_assert(!is_abstract_v<_ElementType>, "aligned_accessor: template argument may not be an abstract class");
+
+ using offset_policy = default_accessor<_ElementType>;
+ using element_type = _ElementType;
+ using reference = _ElementType&;
+ using data_handle_type = _ElementType*;
+
+ static constexpr size_t byte_alignment = _ByteAlignment;
+
+ _LIBCPP_HIDE_FROM_ABI constexpr aligned_accessor() noexcept = default;
+
+ template <class _OtherElementType, size_t _OtherByteAlignment>
+ requires(is_convertible_v<_OtherElementType (*)[], element_type (*)[]> && _OtherByteAlignment >= byte_alignment)
+ _LIBCPP_HIDE_FROM_ABI constexpr aligned_accessor(aligned_accessor<_OtherElementType, _OtherByteAlignment>) noexcept {}
+
+ template <class _OtherElementType>
+ requires(is_convertible_v<_OtherElementType (*)[], element_type (*)[]>)
+ _LIBCPP_HIDE_FROM_ABI explicit constexpr aligned_accessor(default_accessor<_OtherElementType>) noexcept {}
+
+ template <class _OtherElementType>
+ requires(is_convertible_v<element_type (*)[], _OtherElementType (*)[]>)
+ _LIBCPP_HIDE_FROM_ABI constexpr operator default_accessor<_OtherElementType>() const noexcept {
+ return {};
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr reference access(data_handle_type __p, size_t __i) const noexcept {
+ return std::assume_aligned<byte_alignment>(__p)[__i];
+ }
+
+ _LIBCPP_HIDE_FROM_ABI constexpr typename offset_policy::data_handle_type
+ offset(data_handle_type __p, size_t __i) const noexcept {
+ return std::assume_aligned<byte_alignment>(__p) + __i;
+ }
+};
+
+#endif // _LIBCPP_STD_VER >= 26
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___MDSPAN_ALIGNED_ACCESSOR_H
diff --git a/libcxx/include/__mdspan/mdspan.h b/libcxx/include/__mdspan/mdspan.h
index 3f9b35b185b167..ef8db9f1f9789a 100644
--- a/libcxx/include/__mdspan/mdspan.h
+++ b/libcxx/include/__mdspan/mdspan.h
@@ -20,6 +20,7 @@
#include <__assert>
#include <__config>
#include <__fwd/mdspan.h>
+#include <__mdspan/aligned_accessor.h>
#include <__mdspan/default_accessor.h>
#include <__mdspan/extents.h>
#include <__type_traits/extent.h>
@@ -266,13 +267,13 @@ class mdspan {
# if _LIBCPP_STD_VER >= 26
template <class _ElementType, class... _OtherIndexTypes>
requires((is_convertible_v<_OtherIndexTypes, size_t> && ...) && (sizeof...(_OtherIndexTypes) > 0))
-explicit mdspan(_ElementType*,
- _OtherIndexTypes...) -> mdspan<_ElementType, extents<size_t, __maybe_static_ext<_OtherIndexTypes>...>>;
+explicit mdspan(_ElementType*, _OtherIndexTypes...)
+ -> mdspan<_ElementType, extents<size_t, __maybe_static_ext<_OtherIndexTypes>...>>;
# else
template <class _ElementType, class... _OtherIndexTypes>
requires((is_convertible_v<_OtherIndexTypes, size_t> && ...) && (sizeof...(_OtherIndexTypes) > 0))
-explicit mdspan(_ElementType*,
- _OtherIndexTypes...) -> mdspan<_ElementType, dextents<size_t, sizeof...(_OtherIndexTypes)>>;
+explicit mdspan(_ElementType*, _OtherIndexTypes...)
+ -> mdspan<_ElementType, dextents<size_t, sizeof...(_OtherIndexTypes)>>;
# endif
template <class _Pointer>
diff --git a/libcxx/include/__memory/is_sufficiently_aligned.h b/libcxx/include/__memory/is_sufficiently_aligned.h
new file mode 100644
index 00000000000000..4280920cabb4bc
--- /dev/null
+++ b/libcxx/include/__memory/is_sufficiently_aligned.h
@@ -0,0 +1,34 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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___MEMORY_IS_SUFFICIENTLY_ALIGNED_H
+#define _LIBCPP___MEMORY_IS_SUFFICIENTLY_ALIGNED_H
+
+#include <__config>
+#include <__cstddef/size_t.h>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 26
+
+template <size_t _Alignment, class _Tp>
+_LIBCPP_HIDE_FROM_ABI bool is_sufficiently_aligned(_Tp* __ptr) {
+ return reinterpret_cast<uintptr_t>(__ptr) % _Alignment == 0;
+}
+
+#endif // _LIBCPP_STD_VER >= 26
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_IS_SUFFICIENTLY_ALIGNED_H
diff --git a/libcxx/include/mdspan b/libcxx/include/mdspan
index a67ed1834e3bde..61f1b210dd03af 100644
--- a/libcxx/include/mdspan
+++ b/libcxx/include/mdspan
@@ -33,10 +33,14 @@ namespace std {
template<class ElementType>
class default_accessor;
+ // [mdspan.accessor.aligned], class template aligned_accessor
+ template<class ElementType, size_t ByteAlignment>
+ class aligned_accessor; // since C++26
+
// [mdspan.mdspan], class template mdspan
template<class ElementType, class Extents, class LayoutPolicy = layout_right,
class AccessorPolicy = default_accessor<ElementType>>
- class mdspan; // not implemented yet
+ class mdspan;
}
// extents synopsis
@@ -269,6 +273,38 @@ namespace std {
};
}
+// aligned_accessor synopsis
+
+namespace std {
+ template<class ElementType, size_t ByteAlignment>
+ struct aligned_accessor {
+ using offset_policy = default_accessor<ElementType>;
+ using element_type = ElementType;
+ using reference = ElementType&;
+ using data_handle_type = ElementType*;
+
+ static constexpr size_t byte_alignment = ByteAlignment;
+
+ constexpr aligned_accessor() noexcept = default;
+
+ template<class OtherElementType, size_t OtherByteAlignment>
+ constexpr aligned_accessor(
+ aligned_accessor<OtherElementType, OtherByteAlignment>) noexcept;
+
+ template<class OtherElementType>
+ explicit constexpr aligned_accessor(
+ default_accessor<OtherElementType>) noexcept;
+
+ template<class OtherElementType>
+ constexpr operator default_accessor<OtherElementType>() const noexcept;
+
+ constexpr reference access(data_handle_type p, size_t i) const noexcept;
+
+ constexpr typename offset_policy::data_handle_type
+ offset(data_handle_type p, size_t i) const noexcept;
+ };
+}
+
// mdspan synopsis
namespace std {
diff --git a/libcxx/include/memory b/libcxx/include/memory
index fc62606ea0fd33..a6400bd29f4437 100644
--- a/libcxx/include/memory
+++ b/libcxx/include/memory
@@ -912,6 +912,9 @@ void* align(size_t alignment, size_t size, void*& ptr, size_t& space);
template<size_t N, class T>
[[nodiscard]] constexpr T* assume_aligned(T* ptr); // since C++20
+template<size_t Alignment, class T>
+ bool is_sufficiently_aligned(T* ptr); // since C++26
+
// [out.ptr.t], class template out_ptr_t
template<class Smart, class Pointer, class... Args>
class out_ptr_t; // since c++23
@@ -945,6 +948,7 @@ template<class Pointer = void, class Smart, class... Args>
# include <__memory/allocator_traits.h>
# include <__memory/auto_ptr.h>
# include <__memory/inout_ptr.h>
+# include <__memory/is_sufficiently_aligned.h>
# include <__memory/out_ptr.h>
# include <__memory/pointer_traits.h>
# include <__memory/raw_storage_iterator.h>
diff --git a/libcxx/include/module.modulemap b/libcxx/include/module.modulemap
index 07ab5649ae45cb..c4beb2dfa4f383 100644
--- a/libcxx/include/module.modulemap
+++ b/libcxx/include/module.modulemap
@@ -1504,6 +1504,7 @@ module std [system] {
}
module mdspan {
+ module aligned_accessor { header "__mdspan/aligned_accessor.h" }
module default_accessor { header "__mdspan/default_accessor.h" }
module extents { header "__mdspan/extents.h" }
module fwd { header "__fwd/mdspan.h" }
@@ -1539,6 +1540,7 @@ module std [system] {
module destruct_n { header "__memory/destruct_n.h" }
module fwd { header "__fwd/memory.h" }
module inout_ptr { header "__memory/inout_ptr.h" }
+ module is_sufficiently_aligned { header "__memory/is_sufficiently_aligned.h" }
module noexcept_move_assign_container { header "__memory/noexcept_move_assign_container.h" }
module out_ptr { header "__memory/out_ptr.h" }
module pointer_traits { header "__memory/pointer_traits.h" }
diff --git a/libcxx/modules/std/mdspan.inc b/libcxx/modules/std/mdspan.inc
index 5e65993383cdc0..c8cc78badb7d59 100644
--- a/libcxx/modules/std/mdspan.inc
+++ b/libcxx/modules/std/mdspan.inc
@@ -28,6 +28,11 @@ export namespace std {
// [mdspan.accessor.default], class template default_accessor
using std::default_accessor;
+# if _LIBCPP_STD_VER >= 26
+ // [mdspan.accessor.aligned], class template aligned_accessor
+ using std::aligned_accessor;
+# endif // _LIBCPP_STD_VER >= 26
+
// [mdspan.mdspan], class template mdspan
using std::mdspan;
#endif // _LIBCPP_STD_VER >= 23
diff --git a/libcxx/modules/std/memory.inc b/libcxx/modules/std/memory.inc
index 82056e426d06c9..c25e9e3443e9cf 100644
--- a/libcxx/modules/std/memory.inc
+++ b/libcxx/modules/std/memory.inc
@@ -17,6 +17,9 @@ export namespace std {
// [ptr.align], pointer alignment
using std::align;
using std::assume_aligned;
+#if _LIBCPP_STD_VER >= 26
+ using std::is_sufficiently_aligned;
+#endif
// [obj.lifetime], explicit lifetime management
// using std::start_lifetime_as;
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp
new file mode 100644
index 00000000000000..145dc79eda73d4
--- /dev/null
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp
@@ -0,0 +1,61 @@
+//===----------------------------------------------------------------------===//
+//
+// 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++03, c++11, c++14, c++17, c++20, c++23
+
+// <mdspan>
+
+// constexpr reference access(data_handle_type p, size_t i) const noexcept;
+//
+// Effects: Equivalent to: return assume_aligned<byte_alignment>(p)[i];
+
+#include <mdspan>
+#include <cassert>
+#include <type_traits>
+
+#include "test_macros.h"
+
+#include "../MinimalElementType.h"
+
+template <class T, size_t N>
+constexpr void test_access() {
+ ElementPool<std::remove_const_t<T>, 10 + N> data;
+ T* ptr = data.get_ptr();
+ std::aligned_accessor<T, N> acc;
+ for (size_t i = 0; i < 10 + N; i++) {
+ if (reinterpret_cast<std::uintptr_t>(ptr + i) % N == 0) {
+ std::same_as<typename std::aligned_accessor<T, N>::reference> decltype(auto) x = acc.access(ptr, i);
+ ASSERT_NOEXCEPT(acc.access(ptr, i));
+ assert(&x == ptr + i);
+ }
+ }
+}
+
+template <class T>
+constexpr void test_it() {
+ constexpr size_t N = alignof(T);
+ test_access<T, N>();
+ test_access<T, 2 * N>();
+ test_access<T, 4 * N>();
+ test_access<T, 8 * N>();
+ test_access<T, 16 * N>();
+}
+
+constexpr bool test() {
+ test_it<int>();
+ test_it<const int>();
+ test_it<MinimalElementType>();
+ test_it<const MinimalElementType>();
+ return true;
+}
+
+int main(int, char**) {
+ test();
+ //static_assert(test());
+ return 0;
+}
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/byte_alignment.verify.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/byte_alignment.verify.cpp
new file mode 100644
index 00000000000000..fbc8386a72dede
--- /dev/null
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/byte_alignment.verify.cpp
@@ -0,0 +1,29 @@
+//
+// 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++03, c++11, c++14, c++17, c++20, c++23
+
+// <mdspan>
+
+// template<class ElementType, size_t ByteAlignment>
+// class aligned_accessor;
+
+// ByteAlignement is required to be a power of two and greater or equal to alignof(ElementType).
+
+#include <mdspan>
+
+void not_power_of_two() {
+ // expected-error-re@*:* {{static assertion failed {{.*}}aligned_accessor: byte alignment must be a power of two}}
+ [[maybe_unused]] std::aligned_accessor<int, 12> acc;
+}
+
+struct alignas(8) S {};
+
+void insufficiently_aligned() {
+ // expected-error-re@*:* {{static assertion failed {{.*}}aligned_accessor: insufficient byte alignment}}
+ [[maybe_unused]] std::aligned_accessor<S, 4> acc;
+}
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.from.default_accessor.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.from.default_accessor.pass.cpp
new file mode 100644
index 00000000000000..339c12bb7c6c54
--- /dev/null
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.from.default_accessor.pass.cpp
@@ -0,0 +1,81 @@
+//===----------------------------------------------------------------------===//
+//
+// 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++03, c++11, c++14, c++17, c++20, c++23
+
+// <mdspan>
+//
+// template<class OtherElementType>
+// explicit constexpr aligned_accessor(
+// default_accessor<OtherElementType>) noexcept {}
+//
+// Constraints: is_convertible_v<OtherElementType(*)[], element_type(*)[]> is true.
+
+#include <mdspan>
+#include <cassert>
+#include <cstdint>
+#include <type_traits>
+
+#include "test_macros.h"
+
+#include "../MinimalElementType.h"
+
+struct Base {};
+struct Derived : public Base {};
+
+template <class FromT, class ToT, size_t ToN>
+constexpr void test_conversion() {
+ std::default_accessor<FromT> from;
+ ASSERT_NOEXCEPT(std::aligned_accessor<ToT, ToN>(from));
+ [[maybe_unused]] std::aligned_accessor<ToT, ToN> to(from);
+ // check that the constructor is explicit
+ static_assert(std::is_nothrow_constructible_v<std::aligned_accessor<ToT, ToN>, std::default_accessor<ToT>>);
+ static_assert(!std::is_convertible_v<std::default_accessor<ToT>, std::aligned_accessor<ToT, ToN>>);
+}
+
+template <class From, class To>
+constexpr void test_it() {
+ constexpr size_t N = alignof(To);
+ test_conversion<From, To, N>();
+ test_conversion<From, To, 2 * N>();
+ test_conversion<From, To, 4 * N>();
+ test_conversion<From, To, 8 * N>();
+ test_conversion<From, To, 16 * N>();
+ test_conversion<From, To, 32 * N>();
+}
+
+constexpr bool test() {
+ test_it<int, int>();
+ test_it<int, const int>();
+ test_it<const int, const int>();
+ test_it<MinimalElementType, MinimalElementType>();
+ test_it<MinimalElementType, const MinimalElementType>();
+ test_it<const MinimalElementType, const MinimalElementType>();
+
+ // char is convertible to int, but accessors are not
+ static_assert(!std::is_constructible_v<std::aligned_accessor<int, 4>, std::default_accessor<char>>);
+ // don't allow conversion from const elements to non-const
+ static_assert(!std::is_constructible_v<std::aligned_accessor<int, 4>, std::default_accessor<const int>>);
+ // MinimalElementType is constructible from int, but accessors should not be convertible
+ static_assert(!std::is_constructible_v<std::aligned_accessor<MinimalElementType, 8>, std::default_accessor<int>>);
+ // don't allow conversion from const elements to non-const
+ static_assert(!std::is_constructible_v<std::aligned_accessor<MinimalElementType, 16>,
+ std::default_accessor<const MinimalElementType>>);
+ // don't allow conversion from Base to Derived
+ static_assert(!std::is_constructible_v<std::aligned_accessor<Derived, 2>, std::default_accessor<Base>>);
+ // don't allow conversion from Derived to Base
+ static_assert(!std::is_constructible_v<std::aligned_accessor<Base, 2>, std::default_accessor<Derived>>);
+
+ return true;
+}
+
+int main(int, char**) {
+ test();
+ static_assert(test());
+ return 0;
+}
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.pass.cpp
new file mode 100644
index 00000000000000..0cdfc97dea0aae
--- /dev/null
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.pass.cpp
@@ -0,0 +1,104 @@
+//===----------------------------------------------------------------------===//
+//
+// 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++03, c++11, c++14, c++17, c++20, c++23
+
+// <mdspan>
+//
+// template<class OtherElementType, size_t OtherByteAlignment>
+// constexpr aligned_accessor(aligned_accessor<OtherElementType, OtherByteAlignment>) noexcept {}
+//
+// Constraints:
+// - is_convertible_v<OtherElementType(*)[], element_type(*)[]> is true.
+// - OtherByteAlignment >= byte_alignment is true.
+
+#include <mdspan>
+#include <cassert>
+#include <cstdint>
+#include <type_traits>
+
+#include "test_macros.h"
+
+#include "../MinimalElementType.h"
+
+struct Base {};
+struct Derived : public Base {};
+
+template <class FromT, size_t FromN, class ToT, size_t ToN>
+constexpr void test_conversion() {
+ std::aligned_accessor<FromT, FromN> acc_from;
+ ASSERT_NOEXCEPT(std::aligned_accessor<ToT, ToN>(acc_from));
+ [[maybe_unused]] std::aligned_accessor<ToT, ToN> acc_to(acc_from);
+}
+
+template <class From, class To>
+constexpr void test_it() {
+ constexpr size_t N = alignof(From);
+ static_assert(N == alignof(To));
+
+ test_conversion<From, N, To, N>();
+ test_conversion<From, 2 * N, To, N>();
+ test_conversion<From, 4 * N, To, N>();
+ test_conversion<From, 8 * N, To, N>();
+ test_conversion<From, 16 * N, To, N>();
+ test_conversion<From, 32 * N, To, N>();
+
+ test_conversion<From, 2 * N, To, 2 * N>();
+ test_conversion<From, 4 * N, To, 2 * N>();
+ test_conversion<From, 8 * N, To, 2 * N>();
+ test_conversion<From, 16 * N, To, 2 * N>();
+ test_conversion<From, 32 * N, To, 2 * N>();
+
+ test_conversion<From, 4 * N, To, 4 * N>();
+ test_conversion<From, 8 * N, To, 4 * N>();
+ test_conversion<From, 16 * N, To, 4 * N>();
+ test_conversion<From, 32 * N, To, 4 * N>();
+
+ test_conversion<From, 8 * N, To, 8 * N>();
+ test_conversion<From, 16 * N, To, 8 * N>();
+ test_conversion<From, 32 * N, To, 8 * N>();
+
+ test_conversion<From, 16 * N, To, 16 * N>();
+ test_conversion<From, 32 * N, To, 16 * N>();
+
+ test_conversion<From, 32 * N, To, 32 * N>();
+}
+
+constexpr bool test() {
+ test_it<int, int>();
+ test_it<int, const int>();
+ test_it<const int, const int>();
+ test_it<MinimalElementType, MinimalElementType>();
+ test_it<MinimalElementType, const MinimalElementType>();
+ test_it<const MinimalElementType, const MinimalElementType>();
+
+ // char is convertible to int, but accessors are not
+ static_assert(!std::is_constructible_v<std::aligned_accessor<int, 4>, std::aligned_accessor<char, 4>>);
+ // don't allow conversion from const elements to non-const
+ static_assert(!std::is_constructible_v<std::aligned_accessor<int, 4>, std::aligned_accessor<const int, 4>>);
+ // don't allow conversion from less to more alignment
+ static_assert(!std::is_constructible_v<std::aligned_accessor<int, 8>, std::aligned_accessor<int, 4>>);
+ static_assert(!std::is_constructible_v<std::aligned_accessor<const int, 8>, std::aligned_accessor<const int, 4>>);
+ // MinimalElementType is constructible from int, but accessors should not be convertible
+ static_assert(!std::is_constructible_v<std::aligned_accessor<MinimalElementType, 8>, std::aligned_accessor<int, 8>>);
+ // don't allow conversion from const elements to non-const
+ static_assert(!std::is_constructible_v<std::aligned_accessor<MinimalElementType, 16>,
+ std::aligned_accessor<const MinimalElementType, 16>>);
+ // don't allow conversion from Base to Derived
+ static_assert(!std::is_constructible_v<std::aligned_accessor<Derived, 1>, std::aligned_accessor<Base, 1>>);
+ // don't allow conversion from Derived to Base
+ static_assert(!std::is_constructible_v<std::aligned_accessor<Base, 1>, std::aligned_accessor<Derived, 1>>);
+
+ return true;
+}
+
+int main(int, char**) {
+ test();
+ static_assert(test());
+ return 0;
+}
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.default.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.default.pass.cpp
new file mode 100644
index 00000000000000..4e0b4314c51687
--- /dev/null
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.default.pass.cpp
@@ -0,0 +1,56 @@
+//===----------------------------------------------------------------------===//
+//
+// 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++03, c++11, c++14, c++17, c++20, c++23
+
+// <mdspan>
+
+// Test default construction:
+//
+// constexpr aligned_accessor() noexcept = default;
+
+#include <mdspan>
+#include <cassert>
+#include <cstdint>
+#include <type_traits>
+
+#include "test_macros.h"
+
+#include "../MinimalElementType.h"
+
+template <class T, size_t N>
+constexpr void test_construction() {
+ ASSERT_NOEXCEPT(std::aligned_accessor<T, N>{});
+ [[maybe_unused]] std::aligned_accessor<T, N> acc;
+ static_assert(std::is_trivially_default_constructible_v<std::aligned_accessor<T, N>>);
+}
+
+template <class T>
+constexpr void test_it() {
+ constexpr size_t N = alignof(T);
+ test_construction<T, N>();
+ test_construction<T, 2 * N>();
+ test_construction<T, 4 * N>();
+ test_construction<T, 8 * N>();
+ test_construction<T, 16 * N>();
+ test_construction<T, 32 * N>();
+}
+
+constexpr bool test() {
+ test_it<int>();
+ test_it<const int>();
+ test_it<MinimalElementType>();
+ test_it<const MinimalElementType>();
+ return true;
+}
+
+int main(int, char**) {
+ test();
+ static_assert(test());
+ return 0;
+}
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/element_type.verify.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/element_type.verify.cpp
new file mode 100644
index 00000000000000..91510a99aeec9a
--- /dev/null
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/element_type.verify.cpp
@@ -0,0 +1,32 @@
+//
+// 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++03, c++11, c++14, c++17, c++20, c++23
+
+// <mdspan>
+
+// template<class ElementType, size_t ByteAlignment>
+// class aligned_accessor;
+
+// ElementType is required to be a complete object type that is neither an abstract class type nor an array type.
+
+#include <mdspan>
+
+class AbstractClass {
+public:
+ virtual void method() = 0;
+};
+
+void not_abstract_class() {
+ // expected-error-re@*:* {{static assertion failed {{.*}}aligned_accessor: template argument may not be an abstract class}}
+ [[maybe_unused]] std::aligned_accessor<AbstractClass, 8> acc;
+}
+
+void not_array_type() {
+ // expected-error-re@*:* {{static assertion failed {{.*}}aligned_accessor: template argument may not be an array type}}
+ [[maybe_unused]] std::aligned_accessor<int[5], 128> acc;
+}
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp
new file mode 100644
index 00000000000000..de6d2c6ebf121c
--- /dev/null
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp
@@ -0,0 +1,61 @@
+//===----------------------------------------------------------------------===//
+//
+// 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++03, c++11, c++14, c++17, c++20, c++23
+
+// <mdspan>
+
+// constexpr typename offset_policy::data_handle_type offset(data_handle_type p, size_t i) const noexcept;
+//
+// Effects: Equivalent to: return assume_aligned<byte_alignment>(p) + i;
+
+#include <mdspan>
+#include <cassert>
+#include <type_traits>
+
+#include "test_macros.h"
+
+#include "../MinimalElementType.h"
+
+template <class T, size_t N>
+constexpr void test_offset() {
+ ElementPool<std::remove_const_t<T>, 10 + N> data;
+ T* ptr = data.get_ptr();
+ std::aligned_accessor<T, N> acc;
+ for (size_t i = 0; i < 10 + N; i++) {
+ if (reinterpret_cast<std::uintptr_t>(ptr + i) % N == 0) {
+ static_assert(std::is_same_v<decltype(acc.offset(ptr, i)), typename std::default_accessor<T>::data_handle_type>);
+ ASSERT_NOEXCEPT(acc.offset(ptr, i));
+ assert(acc.offset(ptr, i) == ptr + i);
+ }
+ }
+}
+
+template <class T>
+constexpr void test_it() {
+ constexpr size_t N = alignof(T);
+ test_offset<T, N>();
+ test_offset<T, 2 * N>();
+ test_offset<T, 4 * N>();
+ test_offset<T, 8 * N>();
+ test_offset<T, 16 * N>();
+}
+
+constexpr bool test() {
+ test_it<int>();
+ test_it<const int>();
+ test_it<MinimalElementType>();
+ test_it<const MinimalElementType>();
+ return true;
+}
+
+int main(int, char**) {
+ test();
+ //static_assert(test());
+ return 0;
+}
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/operator.conversion.to.default_accessor.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/operator.conversion.to.default_accessor.pass.cpp
new file mode 100644
index 00000000000000..5b72718c89ec2a
--- /dev/null
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/operator.conversion.to.default_accessor.pass.cpp
@@ -0,0 +1,80 @@
+//===----------------------------------------------------------------------===//
+//
+// 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++03, c++11, c++14, c++17, c++20, c++23
+
+// <mdspan>
+//
+// template<class OtherElementType>
+// constexpr operator default_accessor<OtherElementType>() const noexcept;
+//
+// Constraints: is_convertible_v<element_type(*)[], OtherElementType(*)[]> is true.
+
+#include <mdspan>
+#include <cassert>
+#include <cstdint>
+#include <type_traits>
+
+#include "test_macros.h"
+
+#include "../MinimalElementType.h"
+
+struct Base {};
+struct Derived : public Base {};
+
+template <class FromT, size_t FromN, class ToT>
+constexpr void test_conversion() {
+ std::aligned_accessor<FromT, FromN> from;
+ ASSERT_NOEXCEPT(std::default_accessor<ToT>(from));
+ [[maybe_unused]] std::default_accessor<ToT> to(from);
+ // check that the conversion is implicit
+ static_assert(std::is_nothrow_convertible_v<std::aligned_accessor<FromT, FromN>, std::default_accessor<ToT>>);
+ static_assert(std::is_nothrow_constructible_v<std::default_accessor<ToT>, std::aligned_accessor<FromT, FromN>>);
+}
+
+template <class From, class To>
+constexpr void test_it() {
+ constexpr size_t N = alignof(From);
+ test_conversion<From, N, To>();
+ test_conversion<From, 2 * N, To>();
+ test_conversion<From, 4 * N, To>();
+ test_conversion<From, 8 * N, To>();
+ test_conversion<From, 16 * N, To>();
+ test_conversion<From, 32 * N, To>();
+}
+
+constexpr bool test() {
+ test_it<int, int>();
+ test_it<int, const int>();
+ test_it<const int, const int>();
+ test_it<MinimalElementType, MinimalElementType>();
+ test_it<MinimalElementType, const MinimalElementType>();
+ test_it<const MinimalElementType, const MinimalElementType>();
+
+ // char is convertible to int, but accessors are not
+ static_assert(!std::is_constructible_v<std::default_accessor<int>, std::aligned_accessor<char, 4>>);
+ // don't allow conversion from const elements to non-const
+ static_assert(!std::is_constructible_v<std::default_accessor<int>, std::aligned_accessor<const int, 8>>);
+ // MinimalElementType is constructible from int, but accessors should not be convertible
+ static_assert(!std::is_constructible_v<std::default_accessor<MinimalElementType>, std::aligned_accessor<int, 4>>);
+ // don't allow conversion from const elements to non-const
+ static_assert(!std::is_constructible_v<std::default_accessor<MinimalElementType>,
+ std::aligned_accessor<const MinimalElementType, 4>>);
+ // don't allow conversion from Base to Derived
+ static_assert(!std::is_constructible_v<std::default_accessor<Derived>, std::aligned_accessor<Base, 1>>);
+ // don't allow conversion from Derived to Base
+ static_assert(!std::is_constructible_v<std::default_accessor<Base>, std::aligned_accessor<Derived, 1>>);
+
+ return true;
+}
+
+int main(int, char**) {
+ test();
+ static_assert(test());
+ return 0;
+}
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/types.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/types.pass.cpp
new file mode 100644
index 00000000000000..98de91e20c6392
--- /dev/null
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/types.pass.cpp
@@ -0,0 +1,70 @@
+//===----------------------------------------------------------------------===//
+//
+// 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++03, c++11, c++14, c++17, c++20, c++23
+
+// <mdspan>
+
+// template<class ElementType, size_t ByteAlignment>
+// struct aligned_accessor {
+// using offset_policy = default_accessor<ElementType>;
+// using element_type = ElementType;
+// using reference = ElementType&;
+// using data_handle_type = ElementType*;
+//
+// static constexpr size_t byte_alignment = ByteAlignment;
+//
+// ...
+// };
+//
+// Each specialization of aligned_accessor is a trivially copyable type that models semiregular.
+
+#include <mdspan>
+#include <type_traits>
+#include <concepts>
+#include <cassert>
+
+#include "test_macros.h"
+
+#include "../MinimalElementType.h"
+
+template <class T, size_t N>
+void test_types() {
+ using A = std::aligned_accessor<T, N>;
+ ASSERT_SAME_TYPE(typename A::offset_policy, std::default_accessor<T>);
+ ASSERT_SAME_TYPE(typename A::element_type, T);
+ ASSERT_SAME_TYPE(typename A::reference, T&);
+ ASSERT_SAME_TYPE(typename A::data_handle_type, T*);
+
+ ASSERT_SAME_TYPE(decltype(A::byte_alignment), const size_t);
+ static_assert(A::byte_alignment == N);
+
+ static_assert(std::semiregular<A>);
+ static_assert(std::is_trivially_copyable_v<A>);
+
+ LIBCPP_STATIC_ASSERT(std::is_empty_v<A>);
+}
+
+template <class T>
+constexpr void test() {
+ constexpr size_t N = alignof(T);
+ test_types<T, N>();
+ test_types<T, 2 * N>();
+ test_types<T, 4 * N>();
+ test_types<T, 8 * N>();
+ test_types<T, 16 * N>();
+ test_types<T, 32 * N>();
+}
+
+int main(int, char**) {
+ test<int>();
+ test<const int>();
+ test<MinimalElementType>();
+ test<const MinimalElementType>();
+ return 0;
+}
diff --git a/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp b/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp
new file mode 100644
index 00000000000000..38ca87a3a1771a
--- /dev/null
+++ b/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp
@@ -0,0 +1,105 @@
+//===----------------------------------------------------------------------===//
+//
+// 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++03, c++11, c++14, c++17, c++20, c++23
+
+// #include <memory>
+
+// template<size_t Alignment, class T>
+// bool is_sufficiently_aligned(T* ptr);
+//
+//
+
+#include <cassert>
+#include <cstddef>
+#include <memory>
+
+#include "test_macros.h"
+
+template <typename T>
+constexpr void test_is_sufficiently_aligned() {
+ constexpr std::size_t N = alignof(T);
+
+ alignas(8 * N) std::remove_cv_t<T> buf[5];
+
+ assert(std::is_sufficiently_aligned<N>(&buf[0]));
+ assert(std::is_sufficiently_aligned<2 * N>(&buf[0]));
+ assert(std::is_sufficiently_aligned<4 * N>(&buf[0]));
+ assert(std::is_sufficiently_aligned<8 * N>(&buf[0]));
+
+ assert(std::is_sufficiently_aligned<N>(&buf[1]));
+ assert(!std::is_sufficiently_aligned<2 * N>(&buf[1]));
+ assert(!std::is_sufficiently_aligned<4 * N>(&buf[1]));
+ assert(!std::is_sufficiently_aligned<8 * N>(&buf[1]));
+
+ assert(std::is_sufficiently_aligned<N>(&buf[2]));
+ assert(std::is_sufficiently_aligned<2 * N>(&buf[2]));
+ assert(!std::is_sufficiently_aligned<4 * N>(&buf[2]));
+ assert(!std::is_sufficiently_aligned<8 * N>(&buf[2]));
+
+ assert(std::is_sufficiently_aligned<N>(&buf[3]));
+ assert(!std::is_sufficiently_aligned<2 * N>(&buf[3]));
+ assert(!std::is_sufficiently_aligned<4 * N>(&buf[3]));
+ assert(!std::is_sufficiently_aligned<8 * N>(&buf[3]));
+
+ assert(std::is_sufficiently_aligned<N>(&buf[4]));
+ assert(std::is_sufficiently_aligned<2 * N>(&buf[4]));
+ assert(std::is_sufficiently_aligned<4 * N>(&buf[4]));
+ assert(!std::is_sufficiently_aligned<8 * N>(&buf[4]));
+}
+
+template <typename T>
+constexpr void check(T* p) {
+ ASSERT_SAME_TYPE(bool, decltype(std::is_sufficiently_aligned<alignof(T)>(p)));
+ test_is_sufficiently_aligned<T>();
+ test_is_sufficiently_aligned<const T>();
+}
+
+struct S {};
+struct alignas(4) S4 {};
+struct alignas(8) S8 {};
+struct alignas(16) S16 {};
+struct alignas(32) S32 {};
+struct alignas(64) S64 {};
+struct alignas(128) S128 {};
+
+constexpr bool tests() {
+ char c;
+ int i;
+ long l;
+ double d;
+ long double ld;
+ check(&c);
+ check(&i);
+ check(&l);
+ check(&d);
+ check(&ld);
+
+ S s;
+ S4 s4;
+ S8 s8;
+ S16 s16;
+ S32 s32;
+ S64 s64;
+ S128 s128;
+ check(&s);
+ check(&s4);
+ check(&s8);
+ check(&s16);
+ check(&s32);
+ check(&s64);
+ check(&s128);
+
+ return true;
+}
+
+int main(int, char**) {
+ tests();
+
+ return 0;
+}
>From e36bc1cc588e9c668202e789ee3580819d0c438d Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Sat, 11 Jan 2025 21:42:50 -0500
Subject: [PATCH 02/13] Run the generate scripts
---
libcxx/docs/FeatureTestMacroTable.rst | 4 +-
libcxx/include/version | 4 ++
.../mdspan.version.compile.pass.cpp | 28 ++++++++++
.../memory.version.compile.pass.cpp | 28 ++++++++++
.../version.version.compile.pass.cpp | 56 +++++++++++++++++++
.../generate_feature_test_macro_components.py | 10 ++++
6 files changed, 128 insertions(+), 2 deletions(-)
diff --git a/libcxx/docs/FeatureTestMacroTable.rst b/libcxx/docs/FeatureTestMacroTable.rst
index ae8cbe61fd7d17..462b94bc6bc058 100644
--- a/libcxx/docs/FeatureTestMacroTable.rst
+++ b/libcxx/docs/FeatureTestMacroTable.rst
@@ -404,10 +404,10 @@ Status
---------------------------------------------------------- -----------------
**C++26**
----------------------------------------------------------------------------
- ``__cpp_lib_associative_heterogeneous_insertion`` *unimplemented*
- ---------------------------------------------------------- -----------------
``__cpp_lib_aligned_accessor`` ``202411L``
---------------------------------------------------------- -----------------
+ ``__cpp_lib_associative_heterogeneous_insertion`` *unimplemented*
+ ---------------------------------------------------------- -----------------
``__cpp_lib_atomic_min_max`` *unimplemented*
---------------------------------------------------------- -----------------
``__cpp_lib_bind_front`` ``202306L``
diff --git a/libcxx/include/version b/libcxx/include/version
index f5b5e7a906f504..b81bc3458116b3 100644
--- a/libcxx/include/version
+++ b/libcxx/include/version
@@ -16,6 +16,7 @@
Macro name Value Headers
__cpp_lib_adaptor_iterator_pair_constructor 202106L <queue> <stack>
__cpp_lib_addressof_constexpr 201603L <memory>
+__cpp_lib_aligned_accessor 202411L <mdspan>
__cpp_lib_allocate_at_least 202302L <memory>
__cpp_lib_allocator_traits_is_always_equal 201411L <deque> <forward_list> <list>
<map> <memory> <scoped_allocator>
@@ -145,6 +146,7 @@ __cpp_lib_is_nothrow_convertible 201806L <type_traits>
__cpp_lib_is_null_pointer 201309L <type_traits>
__cpp_lib_is_pointer_interconvertible 201907L <type_traits>
__cpp_lib_is_scoped_enum 202011L <type_traits>
+__cpp_lib_is_sufficiently_aligned 202411L <memory>
__cpp_lib_is_swappable 201603L <type_traits>
__cpp_lib_is_virtual_base_of 202406L <type_traits>
__cpp_lib_is_within_lifetime 202306L <type_traits>
@@ -523,6 +525,7 @@ __cpp_lib_void_t 201411L <type_traits>
#endif
#if _LIBCPP_STD_VER >= 26
+# define __cpp_lib_aligned_accessor 202411L
// # define __cpp_lib_associative_heterogeneous_insertion 202306L
// # define __cpp_lib_atomic_min_max 202403L
# undef __cpp_lib_bind_front
@@ -551,6 +554,7 @@ __cpp_lib_void_t 201411L <type_traits>
// # define __cpp_lib_generate_random 202403L
// # define __cpp_lib_hazard_pointer 202306L
// # define __cpp_lib_inplace_vector 202406L
+# define __cpp_lib_is_sufficiently_aligned 202411L
# if __has_builtin(__builtin_is_virtual_base_of)
# define __cpp_lib_is_virtual_base_of 202406L
# endif
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/mdspan.version.compile.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/mdspan.version.compile.pass.cpp
index 64d1c99b223f42..dbba48047949d9 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/mdspan.version.compile.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/mdspan.version.compile.pass.cpp
@@ -16,6 +16,7 @@
// Test the feature test macros defined by <mdspan>
/* Constant Value
+ __cpp_lib_aligned_accessor 202411L [C++26]
__cpp_lib_freestanding_mdspan 202311L [C++26]
__cpp_lib_mdspan 202207L [C++23]
202406L [C++26]
@@ -27,6 +28,10 @@
#if TEST_STD_VER < 14
+# ifdef __cpp_lib_aligned_accessor
+# error "__cpp_lib_aligned_accessor should not be defined before c++26"
+# endif
+
# ifdef __cpp_lib_freestanding_mdspan
# error "__cpp_lib_freestanding_mdspan should not be defined before c++26"
# endif
@@ -41,6 +46,10 @@
#elif TEST_STD_VER == 14
+# ifdef __cpp_lib_aligned_accessor
+# error "__cpp_lib_aligned_accessor should not be defined before c++26"
+# endif
+
# ifdef __cpp_lib_freestanding_mdspan
# error "__cpp_lib_freestanding_mdspan should not be defined before c++26"
# endif
@@ -55,6 +64,10 @@
#elif TEST_STD_VER == 17
+# ifdef __cpp_lib_aligned_accessor
+# error "__cpp_lib_aligned_accessor should not be defined before c++26"
+# endif
+
# ifdef __cpp_lib_freestanding_mdspan
# error "__cpp_lib_freestanding_mdspan should not be defined before c++26"
# endif
@@ -69,6 +82,10 @@
#elif TEST_STD_VER == 20
+# ifdef __cpp_lib_aligned_accessor
+# error "__cpp_lib_aligned_accessor should not be defined before c++26"
+# endif
+
# ifdef __cpp_lib_freestanding_mdspan
# error "__cpp_lib_freestanding_mdspan should not be defined before c++26"
# endif
@@ -83,6 +100,10 @@
#elif TEST_STD_VER == 23
+# ifdef __cpp_lib_aligned_accessor
+# error "__cpp_lib_aligned_accessor should not be defined before c++26"
+# endif
+
# ifdef __cpp_lib_freestanding_mdspan
# error "__cpp_lib_freestanding_mdspan should not be defined before c++26"
# endif
@@ -100,6 +121,13 @@
#elif TEST_STD_VER > 23
+# ifndef __cpp_lib_aligned_accessor
+# error "__cpp_lib_aligned_accessor should be defined in c++26"
+# endif
+# if __cpp_lib_aligned_accessor != 202411L
+# error "__cpp_lib_aligned_accessor should have the value 202411L in c++26"
+# endif
+
# if !defined(_LIBCPP_VERSION)
# ifndef __cpp_lib_freestanding_mdspan
# error "__cpp_lib_freestanding_mdspan should be defined in c++26"
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/memory.version.compile.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/memory.version.compile.pass.cpp
index 0094bed44be071..5d2ce6042bf6bd 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/memory.version.compile.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/memory.version.compile.pass.cpp
@@ -25,6 +25,7 @@
__cpp_lib_constexpr_memory 201811L [C++20]
202202L [C++23]
__cpp_lib_enable_shared_from_this 201603L [C++17]
+ __cpp_lib_is_sufficiently_aligned 202411L [C++26]
__cpp_lib_make_unique 201304L [C++14]
__cpp_lib_out_ptr 202106L [C++23]
202311L [C++26]
@@ -78,6 +79,10 @@
# error "__cpp_lib_enable_shared_from_this should not be defined before c++17"
# endif
+# ifdef __cpp_lib_is_sufficiently_aligned
+# error "__cpp_lib_is_sufficiently_aligned should not be defined before c++26"
+# endif
+
# ifdef __cpp_lib_make_unique
# error "__cpp_lib_make_unique should not be defined before c++14"
# endif
@@ -152,6 +157,10 @@
# error "__cpp_lib_enable_shared_from_this should not be defined before c++17"
# endif
+# ifdef __cpp_lib_is_sufficiently_aligned
+# error "__cpp_lib_is_sufficiently_aligned should not be defined before c++26"
+# endif
+
# ifndef __cpp_lib_make_unique
# error "__cpp_lib_make_unique should be defined in c++14"
# endif
@@ -241,6 +250,10 @@
# error "__cpp_lib_enable_shared_from_this should have the value 201603L in c++17"
# endif
+# ifdef __cpp_lib_is_sufficiently_aligned
+# error "__cpp_lib_is_sufficiently_aligned should not be defined before c++26"
+# endif
+
# ifndef __cpp_lib_make_unique
# error "__cpp_lib_make_unique should be defined in c++17"
# endif
@@ -351,6 +364,10 @@
# error "__cpp_lib_enable_shared_from_this should have the value 201603L in c++20"
# endif
+# ifdef __cpp_lib_is_sufficiently_aligned
+# error "__cpp_lib_is_sufficiently_aligned should not be defined before c++26"
+# endif
+
# ifndef __cpp_lib_make_unique
# error "__cpp_lib_make_unique should be defined in c++20"
# endif
@@ -473,6 +490,10 @@
# error "__cpp_lib_enable_shared_from_this should have the value 201603L in c++23"
# endif
+# ifdef __cpp_lib_is_sufficiently_aligned
+# error "__cpp_lib_is_sufficiently_aligned should not be defined before c++26"
+# endif
+
# ifndef __cpp_lib_make_unique
# error "__cpp_lib_make_unique should be defined in c++23"
# endif
@@ -598,6 +619,13 @@
# error "__cpp_lib_enable_shared_from_this should have the value 201603L in c++26"
# endif
+# ifndef __cpp_lib_is_sufficiently_aligned
+# error "__cpp_lib_is_sufficiently_aligned should be defined in c++26"
+# endif
+# if __cpp_lib_is_sufficiently_aligned != 202411L
+# error "__cpp_lib_is_sufficiently_aligned should have the value 202411L in c++26"
+# endif
+
# ifndef __cpp_lib_make_unique
# error "__cpp_lib_make_unique should be defined in c++26"
# endif
diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/version.version.compile.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/version.version.compile.pass.cpp
index 7c03955df681d5..a8614245028ab7 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/version.version.compile.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/version.version.compile.pass.cpp
@@ -18,6 +18,7 @@
/* Constant Value
__cpp_lib_adaptor_iterator_pair_constructor 202106L [C++23]
__cpp_lib_addressof_constexpr 201603L [C++17]
+ __cpp_lib_aligned_accessor 202411L [C++26]
__cpp_lib_allocate_at_least 202302L [C++23]
__cpp_lib_allocator_traits_is_always_equal 201411L [C++17]
__cpp_lib_any 201606L [C++17]
@@ -132,6 +133,7 @@
__cpp_lib_is_null_pointer 201309L [C++14]
__cpp_lib_is_pointer_interconvertible 201907L [C++20]
__cpp_lib_is_scoped_enum 202011L [C++23]
+ __cpp_lib_is_sufficiently_aligned 202411L [C++26]
__cpp_lib_is_swappable 201603L [C++17]
__cpp_lib_is_virtual_base_of 202406L [C++26]
__cpp_lib_is_within_lifetime 202306L [C++26]
@@ -264,6 +266,10 @@
# error "__cpp_lib_addressof_constexpr should not be defined before c++17"
# endif
+# ifdef __cpp_lib_aligned_accessor
+# error "__cpp_lib_aligned_accessor should not be defined before c++26"
+# endif
+
# ifdef __cpp_lib_allocate_at_least
# error "__cpp_lib_allocate_at_least should not be defined before c++23"
# endif
@@ -704,6 +710,10 @@
# error "__cpp_lib_is_scoped_enum should not be defined before c++23"
# endif
+# ifdef __cpp_lib_is_sufficiently_aligned
+# error "__cpp_lib_is_sufficiently_aligned should not be defined before c++26"
+# endif
+
# ifdef __cpp_lib_is_swappable
# error "__cpp_lib_is_swappable should not be defined before c++17"
# endif
@@ -1126,6 +1136,10 @@
# error "__cpp_lib_addressof_constexpr should not be defined before c++17"
# endif
+# ifdef __cpp_lib_aligned_accessor
+# error "__cpp_lib_aligned_accessor should not be defined before c++26"
+# endif
+
# ifdef __cpp_lib_allocate_at_least
# error "__cpp_lib_allocate_at_least should not be defined before c++23"
# endif
@@ -1590,6 +1604,10 @@
# error "__cpp_lib_is_scoped_enum should not be defined before c++23"
# endif
+# ifdef __cpp_lib_is_sufficiently_aligned
+# error "__cpp_lib_is_sufficiently_aligned should not be defined before c++26"
+# endif
+
# ifdef __cpp_lib_is_swappable
# error "__cpp_lib_is_swappable should not be defined before c++17"
# endif
@@ -2063,6 +2081,10 @@
# error "__cpp_lib_addressof_constexpr should have the value 201603L in c++17"
# endif
+# ifdef __cpp_lib_aligned_accessor
+# error "__cpp_lib_aligned_accessor should not be defined before c++26"
+# endif
+
# ifdef __cpp_lib_allocate_at_least
# error "__cpp_lib_allocate_at_least should not be defined before c++23"
# endif
@@ -2611,6 +2633,10 @@
# error "__cpp_lib_is_scoped_enum should not be defined before c++23"
# endif
+# ifdef __cpp_lib_is_sufficiently_aligned
+# error "__cpp_lib_is_sufficiently_aligned should not be defined before c++26"
+# endif
+
# ifndef __cpp_lib_is_swappable
# error "__cpp_lib_is_swappable should be defined in c++17"
# endif
@@ -3195,6 +3221,10 @@
# error "__cpp_lib_addressof_constexpr should have the value 201603L in c++20"
# endif
+# ifdef __cpp_lib_aligned_accessor
+# error "__cpp_lib_aligned_accessor should not be defined before c++26"
+# endif
+
# ifdef __cpp_lib_allocate_at_least
# error "__cpp_lib_allocate_at_least should not be defined before c++23"
# endif
@@ -3914,6 +3944,10 @@
# error "__cpp_lib_is_scoped_enum should not be defined before c++23"
# endif
+# ifdef __cpp_lib_is_sufficiently_aligned
+# error "__cpp_lib_is_sufficiently_aligned should not be defined before c++26"
+# endif
+
# ifndef __cpp_lib_is_swappable
# error "__cpp_lib_is_swappable should be defined in c++20"
# endif
@@ -4594,6 +4628,10 @@
# error "__cpp_lib_addressof_constexpr should have the value 201603L in c++23"
# endif
+# ifdef __cpp_lib_aligned_accessor
+# error "__cpp_lib_aligned_accessor should not be defined before c++26"
+# endif
+
# ifndef __cpp_lib_allocate_at_least
# error "__cpp_lib_allocate_at_least should be defined in c++23"
# endif
@@ -5388,6 +5426,10 @@
# error "__cpp_lib_is_scoped_enum should have the value 202011L in c++23"
# endif
+# ifdef __cpp_lib_is_sufficiently_aligned
+# error "__cpp_lib_is_sufficiently_aligned should not be defined before c++26"
+# endif
+
# ifndef __cpp_lib_is_swappable
# error "__cpp_lib_is_swappable should be defined in c++23"
# endif
@@ -6215,6 +6257,13 @@
# error "__cpp_lib_addressof_constexpr should have the value 201603L in c++26"
# endif
+# ifndef __cpp_lib_aligned_accessor
+# error "__cpp_lib_aligned_accessor should be defined in c++26"
+# endif
+# if __cpp_lib_aligned_accessor != 202411L
+# error "__cpp_lib_aligned_accessor should have the value 202411L in c++26"
+# endif
+
# ifndef __cpp_lib_allocate_at_least
# error "__cpp_lib_allocate_at_least should be defined in c++26"
# endif
@@ -7201,6 +7250,13 @@
# error "__cpp_lib_is_scoped_enum should have the value 202011L in c++26"
# endif
+# ifndef __cpp_lib_is_sufficiently_aligned
+# error "__cpp_lib_is_sufficiently_aligned should be defined in c++26"
+# endif
+# if __cpp_lib_is_sufficiently_aligned != 202411L
+# error "__cpp_lib_is_sufficiently_aligned should have the value 202411L in c++26"
+# endif
+
# ifndef __cpp_lib_is_swappable
# error "__cpp_lib_is_swappable should be defined in c++26"
# endif
diff --git a/libcxx/utils/generate_feature_test_macro_components.py b/libcxx/utils/generate_feature_test_macro_components.py
index dae827f5de50c2..e35e34bbdd76bc 100755
--- a/libcxx/utils/generate_feature_test_macro_components.py
+++ b/libcxx/utils/generate_feature_test_macro_components.py
@@ -89,6 +89,11 @@ def add_version_header(tc):
"values": {"c++17": 201603},
"headers": ["memory"],
},
+ {
+ "name": "__cpp_lib_aligned_accessor",
+ "values": {"c++26": 202411},
+ "headers": ["mdspan"],
+ },
{
"name": "__cpp_lib_allocate_at_least",
"values": {
@@ -781,6 +786,11 @@ def add_version_header(tc):
"values": {"c++23": 202011},
"headers": ["type_traits"],
},
+ {
+ "name": "__cpp_lib_is_sufficiently_aligned",
+ "values": {"c++26": 202411},
+ "headers": ["memory"],
+ },
{
"name": "__cpp_lib_is_swappable",
"values": {"c++17": 201603},
>From 1c57f2058899cc9ff5f3ecab929a0fe9180464fc Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Sun, 12 Jan 2025 21:49:31 -0500
Subject: [PATCH 03/13] Add missing header include for default_accessor
---
libcxx/include/__mdspan/aligned_accessor.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/libcxx/include/__mdspan/aligned_accessor.h b/libcxx/include/__mdspan/aligned_accessor.h
index 441c144c11aebb..2b8d4c52d87374 100644
--- a/libcxx/include/__mdspan/aligned_accessor.h
+++ b/libcxx/include/__mdspan/aligned_accessor.h
@@ -19,6 +19,7 @@
#include <__config>
#include <__cstddef/size_t.h>
+#include <__mdspan/default_accessor.h>
#include <__memory/assume_aligned.h>
#include <__type_traits/is_abstract.h>
#include <__type_traits/is_array.h>
>From 68ea16753e8303d8015bec1638555f359b52c495 Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Sun, 12 Jan 2025 23:53:39 -0500
Subject: [PATCH 04/13] Missing header includes in tests
---
.../views/mdspan/aligned_accessor/access.pass.cpp | 2 ++
.../views/mdspan/aligned_accessor/offset.pass.cpp | 6 ++++--
.../memory/ptr.align/is_sufficiently_aligned.pass.cpp | 1 +
3 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp
index 145dc79eda73d4..40ec85fe56a4dd 100644
--- a/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp
@@ -16,6 +16,8 @@
#include <mdspan>
#include <cassert>
+#include <cstdint>
+#include <concepts>
#include <type_traits>
#include "test_macros.h"
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp
index de6d2c6ebf121c..64e37fd7344b27 100644
--- a/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp
@@ -16,6 +16,8 @@
#include <mdspan>
#include <cassert>
+#include <cstdint>
+#include <concepts>
#include <type_traits>
#include "test_macros.h"
@@ -29,9 +31,9 @@ constexpr void test_offset() {
std::aligned_accessor<T, N> acc;
for (size_t i = 0; i < 10 + N; i++) {
if (reinterpret_cast<std::uintptr_t>(ptr + i) % N == 0) {
- static_assert(std::is_same_v<decltype(acc.offset(ptr, i)), typename std::default_accessor<T>::data_handle_type>);
+ std::same_as<typename std::default_accessor<T>::data_handle_type> decltype(auto) x = acc.offset(ptr, i);
ASSERT_NOEXCEPT(acc.offset(ptr, i));
- assert(acc.offset(ptr, i) == ptr + i);
+ assert(x == ptr + i);
}
}
}
diff --git a/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp b/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp
index 38ca87a3a1771a..4616018ef87977 100644
--- a/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp
+++ b/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp
@@ -18,6 +18,7 @@
#include <cassert>
#include <cstddef>
#include <memory>
+#include <type_traits>
#include "test_macros.h"
>From 1db762c06622806e15ff5fd65b7cfc4bdd607999 Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Mon, 13 Jan 2025 13:12:29 -0500
Subject: [PATCH 05/13] Fix access and offset tests
Align the pointer and check 10 elements
---
.../views/mdspan/aligned_accessor/access.pass.cpp | 15 ++++++++++-----
.../views/mdspan/aligned_accessor/offset.pass.cpp | 15 ++++++++++-----
2 files changed, 20 insertions(+), 10 deletions(-)
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp
index 40ec85fe56a4dd..70ccaff779c515 100644
--- a/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp
@@ -28,14 +28,19 @@ template <class T, size_t N>
constexpr void test_access() {
ElementPool<std::remove_const_t<T>, 10 + N> data;
T* ptr = data.get_ptr();
- std::aligned_accessor<T, N> acc;
- for (size_t i = 0; i < 10 + N; i++) {
+ // align ptr
+ for (size_t i = 0; i < N; ++i) {
if (reinterpret_cast<std::uintptr_t>(ptr + i) % N == 0) {
- std::same_as<typename std::aligned_accessor<T, N>::reference> decltype(auto) x = acc.access(ptr, i);
- ASSERT_NOEXCEPT(acc.access(ptr, i));
- assert(&x == ptr + i);
+ ptr += i;
+ break;
}
}
+ std::aligned_accessor<T, N> acc;
+ for (size_t i = 0; i < 10; ++i) {
+ std::same_as<typename std::aligned_accessor<T, N>::reference> decltype(auto) x = acc.access(ptr, i);
+ ASSERT_NOEXCEPT(acc.access(ptr, i));
+ assert(&x == ptr + i);
+ }
}
template <class T>
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp
index 64e37fd7344b27..ae4dac5504f66e 100644
--- a/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp
@@ -28,14 +28,19 @@ template <class T, size_t N>
constexpr void test_offset() {
ElementPool<std::remove_const_t<T>, 10 + N> data;
T* ptr = data.get_ptr();
- std::aligned_accessor<T, N> acc;
- for (size_t i = 0; i < 10 + N; i++) {
+ // align ptr
+ for (size_t i = 0; i < N; ++i) {
if (reinterpret_cast<std::uintptr_t>(ptr + i) % N == 0) {
- std::same_as<typename std::default_accessor<T>::data_handle_type> decltype(auto) x = acc.offset(ptr, i);
- ASSERT_NOEXCEPT(acc.offset(ptr, i));
- assert(x == ptr + i);
+ ptr += i;
+ break;
}
}
+ std::aligned_accessor<T, N> acc;
+ for (size_t i = 0; i < 10; ++i) {
+ std::same_as<typename std::default_accessor<T>::data_handle_type> decltype(auto) x = acc.offset(ptr, i);
+ ASSERT_NOEXCEPT(acc.offset(ptr, i));
+ assert(x == ptr + i);
+ }
}
template <class T>
>From d2eccee834ddc65ac7c20fb68a93c311b3a07dc6 Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Fri, 31 Jan 2025 17:27:59 -0500
Subject: [PATCH 06/13] Add a release note
---
libcxx/docs/ReleaseNotes/21.rst | 1 +
1 file changed, 1 insertion(+)
diff --git a/libcxx/docs/ReleaseNotes/21.rst b/libcxx/docs/ReleaseNotes/21.rst
index 82f1de6bad3942..f0fcfc5cb57809 100644
--- a/libcxx/docs/ReleaseNotes/21.rst
+++ b/libcxx/docs/ReleaseNotes/21.rst
@@ -39,6 +39,7 @@ Implemented Papers
------------------
- N4258: Cleaning-up noexcept in the Library (`Github <https://github.com/llvm/llvm-project/issues/99937>`__)
+- P2897R7: ``aligned_accessor``: An mdspan accessor expressing pointer over-alignment (`Github <https://github.com/llvm/llvm-project/issues/118372>`__)
Improvements and New Features
-----------------------------
>From 64f14e789d727f45355ff6dfdec07662a9e47edf Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Fri, 31 Jan 2025 17:32:04 -0500
Subject: [PATCH 07/13] Update release version 20 -> 21
---
libcxx/docs/Status/Cxx2cPapers.csv | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libcxx/docs/Status/Cxx2cPapers.csv b/libcxx/docs/Status/Cxx2cPapers.csv
index 0c31bb58a1c4a9..f086ec08a005f3 100644
--- a/libcxx/docs/Status/Cxx2cPapers.csv
+++ b/libcxx/docs/Status/Cxx2cPapers.csv
@@ -81,7 +81,7 @@
"`P3379R0 <https://wg21.link/P3379R0>`__","Constrain ``std::expected`` equality operators","2024-11 (Wrocław)","","",""
"`P0472R2 <https://wg21.link/P0472R2>`__","Put ``std::monostate`` in ``<utility>``","2024-11 (Wrocław)","","",""
"`P2862R1 <https://wg21.link/P2862R1>`__","``text_encoding::name()`` should never return null values","2024-11 (Wrocław)","","",""
-"`P2897R7 <https://wg21.link/P2897R7>`__","``aligned_accessor``: An ``mdspan`` accessor expressing pointer over-alignment","2024-11 (Wrocław)","|Complete|","20",""
+"`P2897R7 <https://wg21.link/P2897R7>`__","``aligned_accessor``: An ``mdspan`` accessor expressing pointer over-alignment","2024-11 (Wrocław)","|Complete|","21",""
"`P3355R1 <https://wg21.link/P3355R1>`__","Fix ``submdspan`` for C++26","2024-11 (Wrocław)","","",""
"`P3222R0 <https://wg21.link/P3222R0>`__","Fix C++26 by adding transposed special cases for P2642 layouts","2024-11 (Wrocław)","","",""
"`P3050R2 <https://wg21.link/P3050R2>`__","Fix C++26 by optimizing ``linalg::conjugated`` for noncomplex value types","2024-11 (Wrocław)","","",""
>From baefcf92ae9d67f5c5e22042d83cb9b7fae8c5f7 Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Fri, 31 Jan 2025 17:35:42 -0500
Subject: [PATCH 08/13] Fix header include <cstd{int -> def}> and qualify
std::size_t
---
.../ctor.conversion.from.default_accessor.pass.cpp | 6 +++---
.../views/mdspan/aligned_accessor/ctor.conversion.pass.cpp | 6 +++---
.../views/mdspan/aligned_accessor/ctor.default.pass.cpp | 6 +++---
3 files changed, 9 insertions(+), 9 deletions(-)
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.from.default_accessor.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.from.default_accessor.pass.cpp
index 339c12bb7c6c54..3c465e89b77b9a 100644
--- a/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.from.default_accessor.pass.cpp
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.from.default_accessor.pass.cpp
@@ -18,7 +18,7 @@
#include <mdspan>
#include <cassert>
-#include <cstdint>
+#include <cstddef>
#include <type_traits>
#include "test_macros.h"
@@ -28,7 +28,7 @@
struct Base {};
struct Derived : public Base {};
-template <class FromT, class ToT, size_t ToN>
+template <class FromT, class ToT, std::size_t ToN>
constexpr void test_conversion() {
std::default_accessor<FromT> from;
ASSERT_NOEXCEPT(std::aligned_accessor<ToT, ToN>(from));
@@ -40,7 +40,7 @@ constexpr void test_conversion() {
template <class From, class To>
constexpr void test_it() {
- constexpr size_t N = alignof(To);
+ constexpr std::size_t N = alignof(To);
test_conversion<From, To, N>();
test_conversion<From, To, 2 * N>();
test_conversion<From, To, 4 * N>();
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.pass.cpp
index 0cdfc97dea0aae..0263e7c1d2e3a8 100644
--- a/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.pass.cpp
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.conversion.pass.cpp
@@ -19,7 +19,7 @@
#include <mdspan>
#include <cassert>
-#include <cstdint>
+#include <cstddef>
#include <type_traits>
#include "test_macros.h"
@@ -29,7 +29,7 @@
struct Base {};
struct Derived : public Base {};
-template <class FromT, size_t FromN, class ToT, size_t ToN>
+template <class FromT, std::size_t FromN, class ToT, std::size_t ToN>
constexpr void test_conversion() {
std::aligned_accessor<FromT, FromN> acc_from;
ASSERT_NOEXCEPT(std::aligned_accessor<ToT, ToN>(acc_from));
@@ -38,7 +38,7 @@ constexpr void test_conversion() {
template <class From, class To>
constexpr void test_it() {
- constexpr size_t N = alignof(From);
+ constexpr std::size_t N = alignof(From);
static_assert(N == alignof(To));
test_conversion<From, N, To, N>();
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.default.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.default.pass.cpp
index 4e0b4314c51687..a1a2449bd4c679 100644
--- a/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.default.pass.cpp
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/ctor.default.pass.cpp
@@ -16,14 +16,14 @@
#include <mdspan>
#include <cassert>
-#include <cstdint>
+#include <cstddef>
#include <type_traits>
#include "test_macros.h"
#include "../MinimalElementType.h"
-template <class T, size_t N>
+template <class T, std::size_t N>
constexpr void test_construction() {
ASSERT_NOEXCEPT(std::aligned_accessor<T, N>{});
[[maybe_unused]] std::aligned_accessor<T, N> acc;
@@ -32,7 +32,7 @@ constexpr void test_construction() {
template <class T>
constexpr void test_it() {
- constexpr size_t N = alignof(T);
+ constexpr std::size_t N = alignof(T);
test_construction<T, N>();
test_construction<T, 2 * N>();
test_construction<T, 4 * N>();
>From 47d3c567be830ace70ff885087345411f134f61a Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Fri, 31 Jan 2025 17:45:58 -0500
Subject: [PATCH 09/13] Move verify tests to test/libcxx/
---
.../views/mdspan/aligned_accessor/byte_alignment.verify.cpp | 0
.../views/mdspan/aligned_accessor/element_type.verify.cpp | 0
2 files changed, 0 insertions(+), 0 deletions(-)
rename libcxx/test/{std => libcxx}/containers/views/mdspan/aligned_accessor/byte_alignment.verify.cpp (100%)
rename libcxx/test/{std => libcxx}/containers/views/mdspan/aligned_accessor/element_type.verify.cpp (100%)
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/byte_alignment.verify.cpp b/libcxx/test/libcxx/containers/views/mdspan/aligned_accessor/byte_alignment.verify.cpp
similarity index 100%
rename from libcxx/test/std/containers/views/mdspan/aligned_accessor/byte_alignment.verify.cpp
rename to libcxx/test/libcxx/containers/views/mdspan/aligned_accessor/byte_alignment.verify.cpp
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/element_type.verify.cpp b/libcxx/test/libcxx/containers/views/mdspan/aligned_accessor/element_type.verify.cpp
similarity index 100%
rename from libcxx/test/std/containers/views/mdspan/aligned_accessor/element_type.verify.cpp
rename to libcxx/test/libcxx/containers/views/mdspan/aligned_accessor/element_type.verify.cpp
>From eda70390adcc52cfdd545f117d6ddc3637144308 Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Fri, 31 Jan 2025 17:52:29 -0500
Subject: [PATCH 10/13] Drop superfluous constexpr, fix includes, and qualify
std::size_t
---
.../views/mdspan/aligned_accessor/types.pass.cpp | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/types.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/types.pass.cpp
index 98de91e20c6392..1fed971f3bb13a 100644
--- a/libcxx/test/std/containers/views/mdspan/aligned_accessor/types.pass.cpp
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/types.pass.cpp
@@ -25,15 +25,16 @@
// Each specialization of aligned_accessor is a trivially copyable type that models semiregular.
#include <mdspan>
-#include <type_traits>
-#include <concepts>
#include <cassert>
+#include <concepts>
+#include <cstddef>
+#include <type_traits>
#include "test_macros.h"
#include "../MinimalElementType.h"
-template <class T, size_t N>
+template <class T, std::size_t N>
void test_types() {
using A = std::aligned_accessor<T, N>;
ASSERT_SAME_TYPE(typename A::offset_policy, std::default_accessor<T>);
@@ -41,7 +42,7 @@ void test_types() {
ASSERT_SAME_TYPE(typename A::reference, T&);
ASSERT_SAME_TYPE(typename A::data_handle_type, T*);
- ASSERT_SAME_TYPE(decltype(A::byte_alignment), const size_t);
+ ASSERT_SAME_TYPE(decltype(A::byte_alignment), const std::size_t);
static_assert(A::byte_alignment == N);
static_assert(std::semiregular<A>);
@@ -51,8 +52,8 @@ void test_types() {
}
template <class T>
-constexpr void test() {
- constexpr size_t N = alignof(T);
+void test() {
+ constexpr std::size_t N = alignof(T);
test_types<T, N>();
test_types<T, 2 * N>();
test_types<T, 4 * N>();
>From 2cd1d2815ff58131d4a3b899fec3cc8af91382a5 Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Fri, 31 Jan 2025 17:54:55 -0500
Subject: [PATCH 11/13] Drop stray commented empty lines and superfluous
constexpr
---
.../memory/ptr.align/is_sufficiently_aligned.pass.cpp | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp b/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp
index 4616018ef87977..7db3e0cf0e6ba1 100644
--- a/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp
+++ b/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp
@@ -12,8 +12,6 @@
// template<size_t Alignment, class T>
// bool is_sufficiently_aligned(T* ptr);
-//
-//
#include <cassert>
#include <cstddef>
@@ -23,7 +21,7 @@
#include "test_macros.h"
template <typename T>
-constexpr void test_is_sufficiently_aligned() {
+void test_is_sufficiently_aligned() {
constexpr std::size_t N = alignof(T);
alignas(8 * N) std::remove_cv_t<T> buf[5];
@@ -55,7 +53,7 @@ constexpr void test_is_sufficiently_aligned() {
}
template <typename T>
-constexpr void check(T* p) {
+void check(T* p) {
ASSERT_SAME_TYPE(bool, decltype(std::is_sufficiently_aligned<alignof(T)>(p)));
test_is_sufficiently_aligned<T>();
test_is_sufficiently_aligned<const T>();
>From 8376d2ffcaf2bac6b623b410417bceb4692a1461 Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Fri, 31 Jan 2025 18:18:32 -0500
Subject: [PATCH 12/13] Fix access and offset tests to work with constexpr
---
.../mdspan/aligned_accessor/access.pass.cpp | 38 ++++++++++---------
.../mdspan/aligned_accessor/offset.pass.cpp | 38 ++++++++++---------
2 files changed, 42 insertions(+), 34 deletions(-)
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp
index 70ccaff779c515..deca1226e47cae 100644
--- a/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/access.pass.cpp
@@ -16,27 +16,31 @@
#include <mdspan>
#include <cassert>
-#include <cstdint>
+#include <cstddef>
#include <concepts>
#include <type_traits>
#include "test_macros.h"
-#include "../MinimalElementType.h"
+// We are not using MinimalElementType.h because MinimalElementType is not
+// default consructible and uninitialized storage does not work in constexpr.
-template <class T, size_t N>
+// Same as MinimalElementType but with a defaulted default constructor
+struct MyMinimalElementType {
+ int val;
+ constexpr MyMinimalElementType() = default;
+ constexpr MyMinimalElementType(const MyMinimalElementType&) = delete;
+ constexpr explicit MyMinimalElementType(int v) noexcept : val(v) {}
+ constexpr MyMinimalElementType& operator=(const MyMinimalElementType&) = delete;
+};
+
+template <class T, std::size_t N>
constexpr void test_access() {
- ElementPool<std::remove_const_t<T>, 10 + N> data;
- T* ptr = data.get_ptr();
- // align ptr
- for (size_t i = 0; i < N; ++i) {
- if (reinterpret_cast<std::uintptr_t>(ptr + i) % N == 0) {
- ptr += i;
- break;
- }
- }
+ constexpr std::size_t Sz = 10;
+ alignas(N) T data[Sz]{};
+ T* ptr = &data[0];
std::aligned_accessor<T, N> acc;
- for (size_t i = 0; i < 10; ++i) {
+ for (std::size_t i = 0; i < Sz; ++i) {
std::same_as<typename std::aligned_accessor<T, N>::reference> decltype(auto) x = acc.access(ptr, i);
ASSERT_NOEXCEPT(acc.access(ptr, i));
assert(&x == ptr + i);
@@ -45,7 +49,7 @@ constexpr void test_access() {
template <class T>
constexpr void test_it() {
- constexpr size_t N = alignof(T);
+ constexpr std::size_t N = alignof(T);
test_access<T, N>();
test_access<T, 2 * N>();
test_access<T, 4 * N>();
@@ -56,13 +60,13 @@ constexpr void test_it() {
constexpr bool test() {
test_it<int>();
test_it<const int>();
- test_it<MinimalElementType>();
- test_it<const MinimalElementType>();
+ test_it<MyMinimalElementType>();
+ test_it<const MyMinimalElementType>();
return true;
}
int main(int, char**) {
test();
- //static_assert(test());
+ static_assert(test());
return 0;
}
diff --git a/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp b/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp
index ae4dac5504f66e..66c30da787a8d3 100644
--- a/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp
+++ b/libcxx/test/std/containers/views/mdspan/aligned_accessor/offset.pass.cpp
@@ -16,27 +16,31 @@
#include <mdspan>
#include <cassert>
-#include <cstdint>
+#include <cstddef>
#include <concepts>
#include <type_traits>
#include "test_macros.h"
-#include "../MinimalElementType.h"
+// We are not using MinimalElementType.h because MinimalElementType is not
+// default consructible and uninitialized storage does not work in constexpr.
-template <class T, size_t N>
+// Same as MinimalElementType but with a defaulted default constructor
+struct MyMinimalElementType {
+ int val;
+ constexpr MyMinimalElementType() = default;
+ constexpr MyMinimalElementType(const MyMinimalElementType&) = delete;
+ constexpr explicit MyMinimalElementType(int v) noexcept : val(v) {}
+ constexpr MyMinimalElementType& operator=(const MyMinimalElementType&) = delete;
+};
+
+template <class T, std::size_t N>
constexpr void test_offset() {
- ElementPool<std::remove_const_t<T>, 10 + N> data;
- T* ptr = data.get_ptr();
- // align ptr
- for (size_t i = 0; i < N; ++i) {
- if (reinterpret_cast<std::uintptr_t>(ptr + i) % N == 0) {
- ptr += i;
- break;
- }
- }
+ constexpr std::size_t Sz = 10;
+ alignas(N) T data[Sz]{};
+ T* ptr = &data[0];
std::aligned_accessor<T, N> acc;
- for (size_t i = 0; i < 10; ++i) {
+ for (std::size_t i = 0; i < Sz; ++i) {
std::same_as<typename std::default_accessor<T>::data_handle_type> decltype(auto) x = acc.offset(ptr, i);
ASSERT_NOEXCEPT(acc.offset(ptr, i));
assert(x == ptr + i);
@@ -45,7 +49,7 @@ constexpr void test_offset() {
template <class T>
constexpr void test_it() {
- constexpr size_t N = alignof(T);
+ constexpr std::size_t N = alignof(T);
test_offset<T, N>();
test_offset<T, 2 * N>();
test_offset<T, 4 * N>();
@@ -56,13 +60,13 @@ constexpr void test_it() {
constexpr bool test() {
test_it<int>();
test_it<const int>();
- test_it<MinimalElementType>();
- test_it<const MinimalElementType>();
+ test_it<MyMinimalElementType>();
+ test_it<const MyMinimalElementType>();
return true;
}
int main(int, char**) {
test();
- //static_assert(test());
+ static_assert(test());
return 0;
}
>From a863a600b17a14c69921105e97e877b17f38ee7f Mon Sep 17 00:00:00 2001
From: Damien L-G <dalg24 at gmail.com>
Date: Fri, 31 Jan 2025 21:41:34 -0500
Subject: [PATCH 13/13] Correct oversight stray constexpr
---
.../utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp b/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp
index 7db3e0cf0e6ba1..139767d40af3b1 100644
--- a/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp
+++ b/libcxx/test/std/utilities/memory/ptr.align/is_sufficiently_aligned.pass.cpp
@@ -67,7 +67,7 @@ struct alignas(32) S32 {};
struct alignas(64) S64 {};
struct alignas(128) S128 {};
-constexpr bool tests() {
+bool tests() {
char c;
int i;
long l;
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