Update libcxx & libcxxabi to LLVM 17.0.4 (#20707)

On top of the main library code changes, each fix that was necessary for
Emscripten has own commit message within the PR.

Author: aheejin

system/lib/libcxx/CREDITS.TXT

@@ -92,6 +92,11 @@ E: stl@microsoft.com
 E: stl@nuwen.net
 D: Implemented floating-point to_chars.
 
+N: Damien Lebrun-Grandie
+E: dalg24@gmail.com
+E: lebrungrandt@ornl.gov
+D: Implementation of mdspan.
+
 N: Microsoft Corporation
 D: Contributed floating-point to_chars.
 
@@ -149,6 +154,10 @@ N: Stephan Tolksdorf
 E: st@quanttec.com
 D: Minor <atomic> fix
 
+N: Christian Trott
+E: crtrott@sandia.gov
+D: Implementation of mdspan.
+
 N: Ruben Van Boxem
 E: vanboxem dot ruben at gmail dot com
 D: Initial Windows patches.

system/lib/libcxx/include/__algorithm/adjacent_find.h

@@ -20,6 +20,9 @@
 #  pragma GCC system_header
 #endif
 
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
 _LIBCPP_BEGIN_NAMESPACE_STD
 
 template <class _Iter, class _Sent, class _BinaryPredicate>
@@ -50,4 +53,6 @@ adjacent_find(_ForwardIterator __first, _ForwardIterator __last) {
 
 _LIBCPP_END_NAMESPACE_STD
 
+_LIBCPP_POP_MACROS
+
 #endif // _LIBCPP___ALGORITHM_ADJACENT_FIND_H

system/lib/libcxx/include/__algorithm/all_of.h

@@ -19,7 +19,7 @@
 _LIBCPP_BEGIN_NAMESPACE_STD
 
 template <class _InputIterator, class _Predicate>
-_LIBCPP_NODISCARD_EXT inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+_LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
 all_of(_InputIterator __first, _InputIterator __last, _Predicate __pred) {
   for (; __first != __last; ++__first)
     if (!__pred(*__first))

system/lib/libcxx/include/__algorithm/binary_search.h

@@ -37,8 +37,7 @@ _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20
 bool
 binary_search(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value)
 {
-    return std::binary_search(__first, __last, __value,
-                              __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>());
+    return std::binary_search(__first, __last, __value, __less<>());
 }
 
 _LIBCPP_END_NAMESPACE_STD

system/lib/libcxx/include/__algorithm/clamp.h

@@ -19,14 +19,14 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if _LIBCPP_STD_VER > 14
+#if _LIBCPP_STD_VER >= 17
 template<class _Tp, class _Compare>
 _LIBCPP_NODISCARD_EXT inline
 _LIBCPP_INLINE_VISIBILITY constexpr
 const _Tp&
 clamp(const _Tp& __v, const _Tp& __lo, const _Tp& __hi, _Compare __comp)
 {
-    _LIBCPP_ASSERT(!__comp(__hi, __lo), "Bad bounds passed to std::clamp");
+    _LIBCPP_ASSERT_UNCATEGORIZED(!__comp(__hi, __lo), "Bad bounds passed to std::clamp");
     return __comp(__v, __lo) ? __lo : __comp(__hi, __v) ? __hi : __v;
 
 }
@@ -37,7 +37,7 @@ _LIBCPP_INLINE_VISIBILITY constexpr
 const _Tp&
 clamp(const _Tp& __v, const _Tp& __lo, const _Tp& __hi)
 {
-    return _VSTD::clamp(__v, __lo, __hi, __less<_Tp>());
+    return _VSTD::clamp(__v, __lo, __hi, __less<>());
 }
 #endif
 

system/lib/libcxx/include/__algorithm/comp.h

@@ -10,6 +10,8 @@
 #define _LIBCPP___ALGORITHM_COMP_H
 
 #include <__config>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/predicate_traits.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
@@ -24,41 +26,20 @@ struct __equal_to {
   }
 };
 
-template <class _T1, class _T2 = _T1>
-struct __less
-{
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX14
-    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
+template <class _Lhs, class _Rhs>
+struct __is_trivial_equality_predicate<__equal_to, _Lhs, _Rhs> : true_type {};
 
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX14
-    bool operator()(const _T1& __x, const _T2& __y) const {return __x < __y;}
+// The definition is required because __less is part of the ABI, but it's empty
+// because all comparisons should be transparent.
+template <class _T1 = void, class _T2 = _T1>
+struct __less {};
 
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX14
-    bool operator()(const _T2& __x, const _T1& __y) const {return __x < __y;}
-
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX14
-    bool operator()(const _T2& __x, const _T2& __y) const {return __x < __y;}
-};
-
-template <class _T1>
-struct __less<_T1, _T1>
-{
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX14
-    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
-};
-
-template <class _T1>
-struct __less<const _T1, _T1>
-{
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX14
-    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
-};
-
-template <class _T1>
-struct __less<_T1, const _T1>
-{
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX14
-    bool operator()(const _T1& __x, const _T1& __y) const {return __x < __y;}
+template <>
+struct __less<void, void> {
+  template <class _Tp, class _Up>
+  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator()(const _Tp& __lhs, const _Up& __rhs) const {
+    return __lhs < __rhs;
+  }
 };
 
 _LIBCPP_END_NAMESPACE_STD

system/lib/libcxx/include/__algorithm/comp_ref_type.h

@@ -9,8 +9,8 @@
 #ifndef _LIBCPP___ALGORITHM_COMP_REF_TYPE_H
 #define _LIBCPP___ALGORITHM_COMP_REF_TYPE_H
 
+#include <__assert>
 #include <__config>
-#include <__debug>
 #include <__utility/declval.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
@@ -23,11 +23,10 @@ template <class _Compare>
 struct __debug_less
 {
     _Compare &__comp_;
-    _LIBCPP_CONSTEXPR_SINCE_CXX14
-    __debug_less(_Compare& __c) : __comp_(__c) {}
+    _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI __debug_less(_Compare& __c) : __comp_(__c) {}
 
     template <class _Tp, class _Up>
-    _LIBCPP_CONSTEXPR_SINCE_CXX14
+    _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
     bool operator()(const _Tp& __x,  const _Up& __y)
     {
         bool __r = __comp_(__x, __y);
@@ -37,7 +36,7 @@ struct __debug_less
     }
 
     template <class _Tp, class _Up>
-    _LIBCPP_CONSTEXPR_SINCE_CXX14
+    _LIBCPP_CONSTEXPR_SINCE_CXX14 _LIBCPP_HIDE_FROM_ABI
     bool operator()(_Tp& __x,  _Up& __y)
     {
         bool __r = __comp_(__x, __y);
@@ -52,7 +51,7 @@ struct __debug_less
     decltype((void)std::declval<_Compare&>()(
         std::declval<_LHS &>(), std::declval<_RHS &>()))
     __do_compare_assert(int, _LHS & __l, _RHS & __r) {
-        _LIBCPP_DEBUG_ASSERT(!__comp_(__l, __r),
+        _LIBCPP_ASSERT_UNCATEGORIZED(!__comp_(__l, __r),
             "Comparator does not induce a strict weak ordering");
         (void)__l;
         (void)__r;
@@ -66,7 +65,7 @@ struct __debug_less
 
 // Pass the comparator by lvalue reference. Or in debug mode, using a
 // debugging wrapper that stores a reference.
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
+#if _LIBCPP_ENABLE_DEBUG_MODE
 template <class _Comp>
 using __comp_ref_type = __debug_less<_Comp>;
 #else

system/lib/libcxx/include/__algorithm/copy.h

@@ -10,6 +10,7 @@
 #define _LIBCPP___ALGORITHM_COPY_H
 
 #include <__algorithm/copy_move_common.h>
+#include <__algorithm/for_each_segment.h>
 #include <__algorithm/iterator_operations.h>
 #include <__algorithm/min.h>
 #include <__config>
@@ -44,36 +45,34 @@ struct __copy_loop {
     return std::make_pair(std::move(__first), std::move(__result));
   }
 
-  template <class _InIter, class _OutIter, __enable_if_t<__is_segmented_iterator<_InIter>::value, int> = 0>
-  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
-  operator()(_InIter __first, _InIter __last, _OutIter __result) const {
+  template <class _InIter, class _OutIter>
+  struct _CopySegment {
     using _Traits = __segmented_iterator_traits<_InIter>;
-    auto __sfirst = _Traits::__segment(__first);
-    auto __slast  = _Traits::__segment(__last);
-    if (__sfirst == __slast) {
-      auto __iters = std::__copy<_AlgPolicy>(_Traits::__local(__first), _Traits::__local(__last), std::move(__result));
-      return std::make_pair(__last, std::move(__iters.second));
-    }
 
-    __result = std::__copy<_AlgPolicy>(_Traits::__local(__first), _Traits::__end(__sfirst), std::move(__result)).second;
-    ++__sfirst;
-    while (__sfirst != __slast) {
-      __result =
-          std::__copy<_AlgPolicy>(_Traits::__begin(__sfirst), _Traits::__end(__sfirst), std::move(__result)).second;
-      ++__sfirst;
+    _OutIter& __result_;
+
+    _LIBCPP_HIDE_FROM_ABI _CopySegment(_OutIter& __result) : __result_(__result) {}
+
+    _LIBCPP_HIDE_FROM_ABI void
+    operator()(typename _Traits::__local_iterator __lfirst, typename _Traits::__local_iterator __llast) {
+      __result_ = std::__copy<_AlgPolicy>(__lfirst, __llast, std::move(__result_)).second;
     }
-    __result =
-        std::__copy<_AlgPolicy>(_Traits::__begin(__sfirst), _Traits::__local(__last), std::move(__result)).second;
+  };
+
+  template <class _InIter, class _OutIter, __enable_if_t<__is_segmented_iterator<_InIter>::value, int> = 0>
+  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
+  operator()(_InIter __first, _InIter __last, _OutIter __result) const {
+    std::__for_each_segment(__first, __last, _CopySegment<_InIter, _OutIter>(__result));
     return std::make_pair(__last, std::move(__result));
   }
 
   template <class _InIter,
             class _OutIter,
-            __enable_if_t<__is_cpp17_random_access_iterator<_InIter>::value &&
+            __enable_if_t<__has_random_access_iterator_category<_InIter>::value &&
                               !__is_segmented_iterator<_InIter>::value && __is_segmented_iterator<_OutIter>::value,
                           int> = 0>
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
-  operator()(_InIter __first, _InIter __last, _OutIter __result) {
+  operator()(_InIter __first, _InIter __last, _OutIter __result) const {
     using _Traits = __segmented_iterator_traits<_OutIter>;
     using _DiffT  = typename common_type<__iter_diff_t<_InIter>, __iter_diff_t<_OutIter> >::type;
 
@@ -98,8 +97,7 @@ struct __copy_loop {
 
 struct __copy_trivial {
   // At this point, the iterators have been unwrapped so any `contiguous_iterator` has been unwrapped to a pointer.
-  template <class _In, class _Out,
-            __enable_if_t<__can_lower_copy_assignment_to_memmove<_In, _Out>::value, int> = 0>
+  template <class _In, class _Out, __enable_if_t<__can_lower_copy_assignment_to_memmove<_In, _Out>::value, int> = 0>
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_In*, _Out*>
   operator()(_In* __first, _In* __last, _Out* __result) const {
     return std::__copy_trivial_impl(__first, __last, __result);

system/lib/libcxx/include/__algorithm/copy_backward.h

@@ -76,11 +76,11 @@ struct __copy_backward_loop {
 
   template <class _InIter,
             class _OutIter,
-            __enable_if_t<__is_cpp17_random_access_iterator<_InIter>::value &&
+            __enable_if_t<__has_random_access_iterator_category<_InIter>::value &&
                               !__is_segmented_iterator<_InIter>::value && __is_segmented_iterator<_OutIter>::value,
                           int> = 0>
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_InIter, _OutIter>
-  operator()(_InIter __first, _InIter __last, _OutIter __result) {
+  operator()(_InIter __first, _InIter __last, _OutIter __result) const {
     using _Traits           = __segmented_iterator_traits<_OutIter>;
     auto __orig_last        = __last;
     auto __segment_iterator = _Traits::__segment(__result);

system/lib/libcxx/include/__algorithm/copy_move_common.h

@@ -15,6 +15,7 @@
 #include <__config>
 #include <__iterator/iterator_traits.h>
 #include <__memory/pointer_traits.h>
+#include <__string/constexpr_c_functions.h>
 #include <__type_traits/enable_if.h>
 #include <__type_traits/is_always_bitcastable.h>
 #include <__type_traits/is_constant_evaluated.h>
@@ -61,7 +62,8 @@ template <class _In, class _Out>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_In*, _Out*>
 __copy_trivial_impl(_In* __first, _In* __last, _Out* __result) {
   const size_t __n = static_cast<size_t>(__last - __first);
-  ::__builtin_memmove(__result, __first, __n * sizeof(_Out));
+
+  std::__constexpr_memmove(__result, __first, __element_count(__n));
 
   return std::make_pair(__last, __result + __n);
 }
@@ -72,7 +74,7 @@ __copy_backward_trivial_impl(_In* __first, _In* __last, _Out* __result) {
   const size_t __n = static_cast<size_t>(__last - __first);
   __result -= __n;
 
-  ::__builtin_memmove(__result, __first, __n * sizeof(_Out));
+  std::__constexpr_memmove(__result, __first, __element_count(__n));
 
   return std::make_pair(__last, __result);
 }
@@ -119,16 +121,6 @@ __unwrap_and_dispatch(_InIter __first, _Sent __last, _OutIter __out_first) {
   return _Algorithm()(std::move(__first), std::move(__last), std::move(__out_first));
 }
 
-template <class _IterOps, class _InValue, class _OutIter, class = void>
-struct __can_copy_without_conversion : false_type {};
-
-template <class _IterOps, class _InValue, class _OutIter>
-struct __can_copy_without_conversion<
-    _IterOps,
-    _InValue,
-    _OutIter,
-    __enable_if_t<is_same<_InValue, typename _IterOps::template __value_type<_OutIter> >::value> > : true_type {};
-
 template <class _AlgPolicy,
           class _NaiveAlgorithm,
           class _OptimizedAlgorithm,
@@ -137,23 +129,6 @@ template <class _AlgPolicy,
           class _OutIter>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 pair<_InIter, _OutIter>
 __dispatch_copy_or_move(_InIter __first, _Sent __last, _OutIter __out_first) {
-#ifdef _LIBCPP_COMPILER_GCC
-  // GCC doesn't support `__builtin_memmove` during constant evaluation.
-  if (__libcpp_is_constant_evaluated()) {
-    return std::__unwrap_and_dispatch<_NaiveAlgorithm>(std::move(__first), std::move(__last), std::move(__out_first));
-  }
-#else
-  // In Clang, `__builtin_memmove` only supports fully trivially copyable types (just having trivial copy assignment is
-  // insufficient). Also, conversions are not supported.
-  if (__libcpp_is_constant_evaluated()) {
-    using _InValue = typename _IterOps<_AlgPolicy>::template __value_type<_InIter>;
-    if (!is_trivially_copyable<_InValue>::value ||
-        !__can_copy_without_conversion<_IterOps<_AlgPolicy>, _InValue, _OutIter>::value) {
-      return std::__unwrap_and_dispatch<_NaiveAlgorithm>(std::move(__first), std::move(__last), std::move(__out_first));
-    }
-  }
-#endif // _LIBCPP_COMPILER_GCC
-
   using _Algorithm = __overload<_NaiveAlgorithm, _OptimizedAlgorithm>;
   return std::__unwrap_and_dispatch<_Algorithm>(std::move(__first), std::move(__last), std::move(__out_first));
 }