[libcxx-commits] [libcxxabi] [libcxx] [libcxxabi] Dont throw in make exception ptr if __cxa_init_primary_exception is available (PR #65534)

via libcxx-commits libcxx-commits at lists.llvm.org
Wed Sep 27 08:06:18 PDT 2023


https://github.com/itrofimow updated https://github.com/llvm/llvm-project/pull/65534

>From 69215b35c6da130217846062a5b1f38ffdb9ffeb Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Wed, 23 Aug 2023 17:05:14 +0300
Subject: [PATCH 01/14] [libcxx] [libcxxabi] don't throw+catch in
 std::make_exception_ptr, if possible

Differential Revision: https://reviews.llvm.org/D158620
---
 libcxx/include/__exception/exception_ptr.h    | 27 +++++++++++++++++++
 .../runtime/exception_pointer_cxxabi.ipp      | 18 +++++++++++++
 libcxxabi/include/cxxabi.h                    |  7 +++++
 libcxxabi/src/cxa_exception.cpp               | 25 ++++++++++-------
 4 files changed, 68 insertions(+), 9 deletions(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index 970d8196724b7cb..1db0a24be228023 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -14,6 +14,8 @@
 #include <__memory/addressof.h>
 #include <cstddef>
 #include <cstdlib>
+#include <typeinfo>
+#include <type_traits>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
@@ -26,6 +28,18 @@ namespace std { // purposefully not using versioning namespace
 class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
   void* __ptr_;
 
+  template <class _Ep>
+  static inline void __dest_thunk(void *__x) {
+	static_cast<_Ep*>(__x)->~_Ep();
+  }
+
+  static void *init_ex(size_t, std::type_info*, void (*)(void *)) _NOEXCEPT;
+  static void free_ex(void *) _NOEXCEPT;
+  static exception_ptr from_ex_ptr(void *__e) _NOEXCEPT;
+
+  template <class _Ep>
+  friend _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep) _NOEXCEPT;
+
 public:
   _LIBCPP_HIDE_FROM_ABI exception_ptr() _NOEXCEPT : __ptr_() {}
   _LIBCPP_HIDE_FROM_ABI exception_ptr(nullptr_t) _NOEXCEPT : __ptr_() {}
@@ -51,11 +65,24 @@ class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
 template <class _Ep>
 _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+# if defined(LIBCXX_BUILDING_LIBCXXABI)
+  using _Ep2 = typename decay<_Ep>::type;
+  void *__ex = exception_ptr::init_ex(
+    sizeof(_Ep), const_cast<std::type_info*>(&typeid(_Ep)), exception_ptr::__dest_thunk<_Ep2>);
+  try {
+    ::new (__ex) _Ep2(__e);
+    return exception_ptr::from_ex_ptr(__ex);
+  } catch (...) {
+    exception_ptr::free_ex(__ex);
+    return current_exception();
+  }
+# else
   try {
     throw __e;
   } catch (...) {
     return current_exception();
   }
+# endif
 #  else
   ((void)__e);
   std::abort();
diff --git a/libcxx/src/support/runtime/exception_pointer_cxxabi.ipp b/libcxx/src/support/runtime/exception_pointer_cxxabi.ipp
index 33aa94502b73c9d..277c5b867f679a8 100644
--- a/libcxx/src/support/runtime/exception_pointer_cxxabi.ipp
+++ b/libcxx/src/support/runtime/exception_pointer_cxxabi.ipp
@@ -34,6 +34,24 @@ exception_ptr& exception_ptr::operator=(const exception_ptr& other) noexcept
     return *this;
 }
 
+void *exception_ptr::init_ex(size_t size, type_info *tinfo, void (*dest)(void *)) noexcept {
+  void *__ex = __cxa_allocate_exception(size);
+  (void)__cxa_init_primary_exception(__ex, tinfo, dest);
+  return __ex;
+}
+
+void exception_ptr::free_ex(void *thrown_object) noexcept {
+  __cxa_free_exception(thrown_object);
+}
+
+exception_ptr exception_ptr::from_ex_ptr(void *__e) noexcept {
+    exception_ptr ptr;
+    ptr.__ptr_ = __e;
+    __cxa_increment_exception_refcount(ptr.__ptr_);
+
+    return ptr;
+}
+
 nested_exception::nested_exception() noexcept
     : __ptr_(current_exception())
 {
diff --git a/libcxxabi/include/cxxabi.h b/libcxxabi/include/cxxabi.h
index 6f4f823bc273ff3..3fae04e35c39dbd 100644
--- a/libcxxabi/include/cxxabi.h
+++ b/libcxxabi/include/cxxabi.h
@@ -36,6 +36,9 @@ class type_info; // forward declaration
 
 // runtime routines use C calling conventions, but are in __cxxabiv1 namespace
 namespace __cxxabiv1 {
+
+struct __cxa_exception;
+
 extern "C"  {
 
 // 2.4.2 Allocating the Exception Object
@@ -43,6 +46,10 @@ extern _LIBCXXABI_FUNC_VIS void *
 __cxa_allocate_exception(size_t thrown_size) throw();
 extern _LIBCXXABI_FUNC_VIS void
 __cxa_free_exception(void *thrown_exception) throw();
+// This function is an llvm extension
+extern _LIBCXXABI_FUNC_VIS __cxa_exception *
+__cxa_init_primary_exception(void *object, std::type_info* tinfo,
+		void (_LIBCXXABI_DTOR_FUNC *dest)(void *)) throw();
 
 // 2.4.3 Throwing the Exception Object
 extern _LIBCXXABI_FUNC_VIS _LIBCXXABI_NORETURN void
diff --git a/libcxxabi/src/cxa_exception.cpp b/libcxxabi/src/cxa_exception.cpp
index f723ececfe3327a..d3c445f2c10ac8d 100644
--- a/libcxxabi/src/cxa_exception.cpp
+++ b/libcxxabi/src/cxa_exception.cpp
@@ -206,6 +206,20 @@ void __cxa_free_exception(void *thrown_object) throw() {
     __aligned_free_with_fallback((void *)raw_buffer);
 }
 
+__cxa_exception *__cxa_init_primary_exception(void *object, std::type_info* tinfo,
+		void (_LIBCXXABI_DTOR_FUNC *dest)(void *)) throw() {
+    __cxa_exception* exception_header = cxa_exception_from_thrown_object(object);
+    exception_header->referenceCount = 0;
+    exception_header->unexpectedHandler = std::get_unexpected();
+    exception_header->terminateHandler  = std::get_terminate();
+    exception_header->exceptionType = tinfo;
+    exception_header->exceptionDestructor = dest;
+    setOurExceptionClass(&exception_header->unwindHeader);
+    exception_header->unwindHeader.exception_cleanup = exception_cleanup_func;
+
+    return exception_header;
+}
+
 
 //  This function shall allocate a __cxa_dependent_exception and
 //  return a pointer to it. (Really to the object, not past its' end).
@@ -261,17 +275,10 @@ __cxa_throw(void *thrown_object, std::type_info *tinfo, void *(_LIBCXXABI_DTOR_F
 __cxa_throw(void *thrown_object, std::type_info *tinfo, void (_LIBCXXABI_DTOR_FUNC *dest)(void *)) {
 #endif
     __cxa_eh_globals *globals = __cxa_get_globals();
-    __cxa_exception* exception_header = cxa_exception_from_thrown_object(thrown_object);
-
-    exception_header->unexpectedHandler = std::get_unexpected();
-    exception_header->terminateHandler  = std::get_terminate();
-    exception_header->exceptionType = tinfo;
-    exception_header->exceptionDestructor = dest;
-    setOurExceptionClass(&exception_header->unwindHeader);
-    exception_header->referenceCount = 1;  // This is a newly allocated exception, no need for thread safety.
     globals->uncaughtExceptions += 1;   // Not atomically, since globals are thread-local
 
-    exception_header->unwindHeader.exception_cleanup = exception_cleanup_func;
+    __cxa_exception *exception_header = __cxa_init_primary_exception(thrown_object, tinfo, dest);
+    exception_header->referenceCount = 1;  // This is a newly allocated exception, no need for thread safety.
 
 #if __has_feature(address_sanitizer)
     // Inform the ASan runtime that now might be a good time to clean stuff up.

>From 9165594a0ef3f5b4fb390ba84fa37fe3b334ab9f Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Wed, 23 Aug 2023 17:53:38 +0300
Subject: [PATCH 02/14] + clang-format

---
 libcxx/include/__exception/exception_ptr.h | 22 +++++++++++-----------
 libcxxabi/include/cxxabi.h                 |  5 ++---
 libcxxabi/src/cxa_exception.cpp            | 13 ++++++-------
 3 files changed, 19 insertions(+), 21 deletions(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index 1db0a24be228023..6ca4e9314f1bd14 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -14,8 +14,8 @@
 #include <__memory/addressof.h>
 #include <cstddef>
 #include <cstdlib>
-#include <typeinfo>
 #include <type_traits>
+#include <typeinfo>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
@@ -29,13 +29,13 @@ class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
   void* __ptr_;
 
   template <class _Ep>
-  static inline void __dest_thunk(void *__x) {
-	static_cast<_Ep*>(__x)->~_Ep();
+  static inline void __dest_thunk(void* __x) {
+    static_cast<_Ep*>(__x)->~_Ep();
   }
 
-  static void *init_ex(size_t, std::type_info*, void (*)(void *)) _NOEXCEPT;
-  static void free_ex(void *) _NOEXCEPT;
-  static exception_ptr from_ex_ptr(void *__e) _NOEXCEPT;
+  static void* init_ex(size_t, std::type_info*, void (*)(void*)) _NOEXCEPT;
+  static void free_ex(void*) _NOEXCEPT;
+  static exception_ptr from_ex_ptr(void* __e) _NOEXCEPT;
 
   template <class _Ep>
   friend _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep) _NOEXCEPT;
@@ -65,10 +65,10 @@ class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
 template <class _Ep>
 _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
-# if defined(LIBCXX_BUILDING_LIBCXXABI)
+#    if defined(LIBCXX_BUILDING_LIBCXXABI)
   using _Ep2 = typename decay<_Ep>::type;
-  void *__ex = exception_ptr::init_ex(
-    sizeof(_Ep), const_cast<std::type_info*>(&typeid(_Ep)), exception_ptr::__dest_thunk<_Ep2>);
+  void* __ex =
+      exception_ptr::init_ex(sizeof(_Ep), const_cast<std::type_info*>(&typeid(_Ep)), exception_ptr::__dest_thunk<_Ep2>);
   try {
     ::new (__ex) _Ep2(__e);
     return exception_ptr::from_ex_ptr(__ex);
@@ -76,13 +76,13 @@ _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
     exception_ptr::free_ex(__ex);
     return current_exception();
   }
-# else
+#    else
   try {
     throw __e;
   } catch (...) {
     return current_exception();
   }
-# endif
+#    endif
 #  else
   ((void)__e);
   std::abort();
diff --git a/libcxxabi/include/cxxabi.h b/libcxxabi/include/cxxabi.h
index 3fae04e35c39dbd..03ec7986e209126 100644
--- a/libcxxabi/include/cxxabi.h
+++ b/libcxxabi/include/cxxabi.h
@@ -47,9 +47,8 @@ __cxa_allocate_exception(size_t thrown_size) throw();
 extern _LIBCXXABI_FUNC_VIS void
 __cxa_free_exception(void *thrown_exception) throw();
 // This function is an llvm extension
-extern _LIBCXXABI_FUNC_VIS __cxa_exception *
-__cxa_init_primary_exception(void *object, std::type_info* tinfo,
-		void (_LIBCXXABI_DTOR_FUNC *dest)(void *)) throw();
+extern _LIBCXXABI_FUNC_VIS __cxa_exception*
+__cxa_init_primary_exception(void* object, std::type_info* tinfo, void(_LIBCXXABI_DTOR_FUNC* dest)(void*)) throw();
 
 // 2.4.3 Throwing the Exception Object
 extern _LIBCXXABI_FUNC_VIS _LIBCXXABI_NORETURN void
diff --git a/libcxxabi/src/cxa_exception.cpp b/libcxxabi/src/cxa_exception.cpp
index d3c445f2c10ac8d..1e72d7f34f26a21 100644
--- a/libcxxabi/src/cxa_exception.cpp
+++ b/libcxxabi/src/cxa_exception.cpp
@@ -206,12 +206,12 @@ void __cxa_free_exception(void *thrown_object) throw() {
     __aligned_free_with_fallback((void *)raw_buffer);
 }
 
-__cxa_exception *__cxa_init_primary_exception(void *object, std::type_info* tinfo,
-		void (_LIBCXXABI_DTOR_FUNC *dest)(void *)) throw() {
+__cxa_exception* __cxa_init_primary_exception(void* object, std::type_info* tinfo,
+                                              void(_LIBCXXABI_DTOR_FUNC* dest)(void*)) throw() {
     __cxa_exception* exception_header = cxa_exception_from_thrown_object(object);
     exception_header->referenceCount = 0;
     exception_header->unexpectedHandler = std::get_unexpected();
-    exception_header->terminateHandler  = std::get_terminate();
+    exception_header->terminateHandler = std::get_terminate();
     exception_header->exceptionType = tinfo;
     exception_header->exceptionDestructor = dest;
     setOurExceptionClass(&exception_header->unwindHeader);
@@ -220,7 +220,6 @@ __cxa_exception *__cxa_init_primary_exception(void *object, std::type_info* tinf
     return exception_header;
 }
 
-
 //  This function shall allocate a __cxa_dependent_exception and
 //  return a pointer to it. (Really to the object, not past its' end).
 //  Otherwise, it will work like __cxa_allocate_exception.
@@ -274,11 +273,11 @@ __cxa_throw(void *thrown_object, std::type_info *tinfo, void *(_LIBCXXABI_DTOR_F
 #else
 __cxa_throw(void *thrown_object, std::type_info *tinfo, void (_LIBCXXABI_DTOR_FUNC *dest)(void *)) {
 #endif
-    __cxa_eh_globals *globals = __cxa_get_globals();
+    __cxa_eh_globals* globals = __cxa_get_globals();
     globals->uncaughtExceptions += 1;   // Not atomically, since globals are thread-local
 
-    __cxa_exception *exception_header = __cxa_init_primary_exception(thrown_object, tinfo, dest);
-    exception_header->referenceCount = 1;  // This is a newly allocated exception, no need for thread safety.
+    __cxa_exception* exception_header = __cxa_init_primary_exception(thrown_object, tinfo, dest);
+    exception_header->referenceCount = 1; // This is a newly allocated exception, no need for thread safety.
 
 #if __has_feature(address_sanitizer)
     // Inform the ASan runtime that now might be a good time to clean stuff up.

>From 6d1f4fbbc54666a55efcc70f2721e5ee9b17a1dc Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Wed, 23 Aug 2023 20:18:45 +0300
Subject: [PATCH 03/14] cleanup

---
 libcxx/include/CMakeLists.txt                 |   1 +
 libcxx/include/__exception/exception_ptr.h    |  18 +-
 libcxx/include/__typeinfo/typeinfo.h          | 333 ++++++++++++++++++
 libcxx/include/module.modulemap.in            |   2 +
 libcxx/include/typeinfo                       |   9 +-
 .../runtime/exception_pointer_cxxabi.ipp      |  21 +-
 6 files changed, 361 insertions(+), 23 deletions(-)
 create mode 100644 libcxx/include/__typeinfo/typeinfo.h

diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index 2ec755236dbaee2..484efde56a82e32 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -694,6 +694,7 @@ set(files
   __tuple/tuple_like_ext.h
   __tuple/tuple_size.h
   __tuple/tuple_types.h
+  __typeinfo/typeinfo.h
   __type_traits/add_const.h
   __type_traits/add_cv.h
   __type_traits/add_lvalue_reference.h
diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index 6ca4e9314f1bd14..0e5310c767cbe92 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -12,10 +12,10 @@
 #include <__config>
 #include <__exception/operations.h>
 #include <__memory/addressof.h>
+#include <__typeinfo/typeinfo.h>
 #include <cstddef>
 #include <cstdlib>
 #include <type_traits>
-#include <typeinfo>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
@@ -28,17 +28,19 @@ namespace std { // purposefully not using versioning namespace
 class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
   void* __ptr_;
 
+#  if defined(LIBCXX_BUILDING_LIBCXXABI)
   template <class _Ep>
   static inline void __dest_thunk(void* __x) {
     static_cast<_Ep*>(__x)->~_Ep();
   }
 
-  static void* init_ex(size_t, std::type_info*, void (*)(void*)) _NOEXCEPT;
-  static void free_ex(void*) _NOEXCEPT;
-  static exception_ptr from_ex_ptr(void* __e) _NOEXCEPT;
+  static void* __init_native_exception(size_t, std::type_info*, void (*)(void*)) _NOEXCEPT;
+  static void __free_native_exception(void*) _NOEXCEPT;
+  static exception_ptr __from_native_exception_pointer(void* __e) _NOEXCEPT;
 
   template <class _Ep>
   friend _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep) _NOEXCEPT;
+#  endif
 
 public:
   _LIBCPP_HIDE_FROM_ABI exception_ptr() _NOEXCEPT : __ptr_() {}
@@ -67,13 +69,13 @@ _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
 #  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
 #    if defined(LIBCXX_BUILDING_LIBCXXABI)
   using _Ep2 = typename decay<_Ep>::type;
-  void* __ex =
-      exception_ptr::init_ex(sizeof(_Ep), const_cast<std::type_info*>(&typeid(_Ep)), exception_ptr::__dest_thunk<_Ep2>);
+  void* __ex = exception_ptr::__init_native_exception(
+      sizeof(_Ep), const_cast<std::type_info*>(&typeid(_Ep)), exception_ptr::__dest_thunk<_Ep2>);
   try {
     ::new (__ex) _Ep2(__e);
-    return exception_ptr::from_ex_ptr(__ex);
+    return exception_ptr::__from_native_exception_pointer(__ex);
   } catch (...) {
-    exception_ptr::free_ex(__ex);
+    exception_ptr::__free_native_exception(__ex);
     return current_exception();
   }
 #    else
diff --git a/libcxx/include/__typeinfo/typeinfo.h b/libcxx/include/__typeinfo/typeinfo.h
new file mode 100644
index 000000000000000..64b50711bbfd4e4
--- /dev/null
+++ b/libcxx/include/__typeinfo/typeinfo.h
@@ -0,0 +1,333 @@
+// -*- 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___TYPEINFO_TYPEINFO_H
+#define _LIBCPP___TYPEINFO_TYPEINFO_H
+
+#include <__availability>
+#include <__config>
+#include <__exception/exception.h>
+#include <__type_traits/is_constant_evaluated.h>
+#include <__verbose_abort>
+#include <cstddef>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+#if defined(_LIBCPP_ABI_VCRUNTIME)
+#  include <vcruntime_typeinfo.h>
+#else
+
+namespace std // purposefully not using versioning namespace
+{
+
+#  if defined(_LIBCPP_ABI_MICROSOFT)
+
+class _LIBCPP_EXPORTED_FROM_ABI type_info {
+  type_info& operator=(const type_info&);
+  type_info(const type_info&);
+
+  mutable struct {
+    const char* __undecorated_name;
+    const char __decorated_name[1];
+  } __data;
+
+  int __compare(const type_info& __rhs) const _NOEXCEPT;
+
+public:
+  _LIBCPP_AVAILABILITY_TYPEINFO_VTABLE
+  virtual ~type_info();
+
+  const char* name() const _NOEXCEPT;
+
+  _LIBCPP_INLINE_VISIBILITY bool before(const type_info& __arg) const _NOEXCEPT { return __compare(__arg) < 0; }
+
+  size_t hash_code() const _NOEXCEPT;
+
+  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator==(const type_info& __arg) const _NOEXCEPT {
+    // When evaluated in a constant expression, both type infos simply can't come
+    // from different translation units, so it is sufficient to compare their addresses.
+    if (__libcpp_is_constant_evaluated()) {
+      return this == &__arg;
+    }
+    return __compare(__arg) == 0;
+  }
+
+#    if _LIBCPP_STD_VER <= 17
+  _LIBCPP_INLINE_VISIBILITY bool operator!=(const type_info& __arg) const _NOEXCEPT { return !operator==(__arg); }
+#    endif
+};
+
+#  else // !defined(_LIBCPP_ABI_MICROSOFT)
+
+// ========================================================================== //
+//                           Implementations
+// ========================================================================== //
+// ------------------------------------------------------------------------- //
+//                               Unique
+//               (_LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION = 1)
+// ------------------------------------------------------------------------- //
+// This implementation of type_info assumes a unique copy of the RTTI for a
+// given type inside a program. This is a valid assumption when abiding to the
+// Itanium ABI (http://itanium-cxx-abi.github.io/cxx-abi/abi.html#vtable-components).
+// Under this assumption, we can always compare the addresses of the type names
+// to implement equality-comparison of type_infos instead of having to perform
+// a deep string comparison.
+// -------------------------------------------------------------------------- //
+//                             NonUnique
+//               (_LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION = 2)
+// -------------------------------------------------------------------------- //
+// This implementation of type_info does not assume there is always a unique
+// copy of the RTTI for a given type inside a program. For various reasons
+// the linker may have failed to merge every copy of a types RTTI
+// (For example: -Bsymbolic or llvm.org/PR37398). Under this assumption, two
+// type_infos are equal if their addresses are equal or if a deep string
+// comparison is equal.
+// -------------------------------------------------------------------------- //
+//                          NonUniqueARMRTTIBit
+//               (_LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION = 3)
+// -------------------------------------------------------------------------- //
+// This implementation is specific to ARM64 on Apple platforms.
+//
+// This implementation of type_info does not assume always a unique copy of
+// the RTTI for a given type inside a program. When constructing the type_info,
+// the compiler packs the pointer to the type name into a uintptr_t and reserves
+// the high bit of that pointer, which is assumed to be free for use under that
+// ABI. If that high bit is set, that specific copy of the RTTI can't be assumed
+// to be unique within the program. If the high bit is unset, then the RTTI can
+// be assumed to be unique within the program.
+//
+// When comparing type_infos, if both RTTIs can be assumed to be unique, it
+// suffices to compare their addresses. If both the RTTIs can't be assumed to
+// be unique, we must perform a deep string comparison of the type names.
+// However, if one of the RTTIs is guaranteed unique and the other one isn't,
+// then both RTTIs are necessarily not to be considered equal.
+//
+// The intent of this design is to remove the need for weak symbols. Specifically,
+// if a type would normally have a default-visibility RTTI emitted as a weak
+// symbol, it is given hidden visibility instead and the non-unique bit is set.
+// Otherwise, types declared with hidden visibility are always considered to have
+// a unique RTTI: the RTTI is emitted with linkonce_odr linkage and is assumed
+// to be deduplicated by the linker within the linked image. Across linked image
+// boundaries, such types are thus considered different types.
+
+// This value can be overriden in the __config_site. When it's not overriden,
+// we pick a default implementation based on the platform here.
+#    ifndef _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION
+
+// Windows and AIX binaries can't merge typeinfos, so use the NonUnique implementation.
+#      if defined(_LIBCPP_OBJECT_FORMAT_COFF) || defined(_LIBCPP_OBJECT_FORMAT_XCOFF)
+#        define _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION 2
+
+// On arm64 on Apple platforms, use the special NonUniqueARMRTTIBit implementation.
+#      elif defined(__APPLE__) && defined(__LP64__) && !defined(__x86_64__)
+#        define _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION 3
+
+// On all other platforms, assume the Itanium C++ ABI and use the Unique implementation.
+#      else
+#        define _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION 1
+#      endif
+#    endif
+
+struct __type_info_implementations {
+  struct __string_impl_base {
+    typedef const char* __type_name_t;
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR static const char*
+    __type_name_to_string(__type_name_t __v) _NOEXCEPT {
+      return __v;
+    }
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR static __type_name_t
+    __string_to_type_name(const char* __v) _NOEXCEPT {
+      return __v;
+    }
+  };
+
+  struct __unique_impl : __string_impl_base {
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE static size_t __hash(__type_name_t __v) _NOEXCEPT {
+      return reinterpret_cast<size_t>(__v);
+    }
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE static bool
+    __eq(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
+      return __lhs == __rhs;
+    }
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE static bool
+    __lt(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
+      return __lhs < __rhs;
+    }
+  };
+
+  struct __non_unique_impl : __string_impl_base {
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE static size_t __hash(__type_name_t __ptr) _NOEXCEPT {
+      size_t __hash = 5381;
+      while (unsigned char __c = static_cast<unsigned char>(*__ptr++))
+        __hash = (__hash * 33) ^ __c;
+      return __hash;
+    }
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE static bool
+    __eq(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
+      return __lhs == __rhs || __builtin_strcmp(__lhs, __rhs) == 0;
+    }
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE static bool
+    __lt(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
+      return __builtin_strcmp(__lhs, __rhs) < 0;
+    }
+  };
+
+  struct __non_unique_arm_rtti_bit_impl {
+    typedef uintptr_t __type_name_t;
+
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE static const char*
+    __type_name_to_string(__type_name_t __v) _NOEXCEPT {
+      return reinterpret_cast<const char*>(__v & ~__non_unique_rtti_bit::value);
+    }
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE static __type_name_t
+    __string_to_type_name(const char* __v) _NOEXCEPT {
+      return reinterpret_cast<__type_name_t>(__v);
+    }
+
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE static size_t __hash(__type_name_t __v) _NOEXCEPT {
+      if (__is_type_name_unique(__v))
+        return __v;
+      return __non_unique_impl::__hash(__type_name_to_string(__v));
+    }
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE static bool
+    __eq(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
+      if (__lhs == __rhs)
+        return true;
+      if (__is_type_name_unique(__lhs) || __is_type_name_unique(__rhs))
+        // Either both are unique and have a different address, or one of them
+        // is unique and the other one isn't. In both cases they are unequal.
+        return false;
+      return __builtin_strcmp(__type_name_to_string(__lhs), __type_name_to_string(__rhs)) == 0;
+    }
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE static bool
+    __lt(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
+      if (__is_type_name_unique(__lhs) || __is_type_name_unique(__rhs))
+        return __lhs < __rhs;
+      return __builtin_strcmp(__type_name_to_string(__lhs), __type_name_to_string(__rhs)) < 0;
+    }
+
+  private:
+    // The unique bit is the top bit. It is expected that __type_name_t is 64 bits when
+    // this implementation is actually used.
+    typedef integral_constant<__type_name_t, (1ULL << ((__CHAR_BIT__ * sizeof(__type_name_t)) - 1))>
+        __non_unique_rtti_bit;
+
+    _LIBCPP_INLINE_VISIBILITY static bool __is_type_name_unique(__type_name_t __lhs) _NOEXCEPT {
+      return !(__lhs & __non_unique_rtti_bit::value);
+    }
+  };
+
+  typedef
+#    if _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION == 1
+      __unique_impl
+#    elif _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION == 2
+      __non_unique_impl
+#    elif _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION == 3
+      __non_unique_arm_rtti_bit_impl
+#    else
+#      error invalid configuration for _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION
+#    endif
+          __impl;
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI type_info {
+  type_info& operator=(const type_info&);
+  type_info(const type_info&);
+
+protected:
+  typedef __type_info_implementations::__impl __impl;
+
+  __impl::__type_name_t __type_name;
+
+  _LIBCPP_INLINE_VISIBILITY explicit type_info(const char* __n) : __type_name(__impl::__string_to_type_name(__n)) {}
+
+public:
+  _LIBCPP_AVAILABILITY_TYPEINFO_VTABLE
+  virtual ~type_info();
+
+  _LIBCPP_INLINE_VISIBILITY const char* name() const _NOEXCEPT { return __impl::__type_name_to_string(__type_name); }
+
+  _LIBCPP_INLINE_VISIBILITY bool before(const type_info& __arg) const _NOEXCEPT {
+    return __impl::__lt(__type_name, __arg.__type_name);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY size_t hash_code() const _NOEXCEPT { return __impl::__hash(__type_name); }
+
+  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator==(const type_info& __arg) const _NOEXCEPT {
+    // When evaluated in a constant expression, both type infos simply can't come
+    // from different translation units, so it is sufficient to compare their addresses.
+    if (__libcpp_is_constant_evaluated()) {
+      return this == &__arg;
+    }
+    return __impl::__eq(__type_name, __arg.__type_name);
+  }
+
+#    if _LIBCPP_STD_VER <= 17
+  _LIBCPP_INLINE_VISIBILITY bool operator!=(const type_info& __arg) const _NOEXCEPT { return !operator==(__arg); }
+#    endif
+};
+#  endif // defined(_LIBCPP_ABI_MICROSOFT)
+
+class _LIBCPP_EXPORTED_FROM_ABI bad_cast : public exception {
+public:
+  bad_cast() _NOEXCEPT;
+  _LIBCPP_HIDE_FROM_ABI bad_cast(const bad_cast&) _NOEXCEPT = default;
+  ~bad_cast() _NOEXCEPT override;
+  const char* what() const _NOEXCEPT override;
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI bad_typeid : public exception {
+public:
+  bad_typeid() _NOEXCEPT;
+  ~bad_typeid() _NOEXCEPT override;
+  const char* what() const _NOEXCEPT override;
+};
+
+} // namespace std
+
+#endif   // defined(_LIBCPP_ABI_VCRUNTIME)
+
+#if defined(_LIBCPP_ABI_VCRUNTIME) && _HAS_EXCEPTIONS == 0
+
+namespace std {
+
+class bad_cast : public exception {
+public:
+  bad_cast() _NOEXCEPT : exception("bad cast") {}
+
+private:
+  bad_cast(const char* const __message) _NOEXCEPT : exception(__message) {}
+};
+
+class bad_typeid : public exception {
+public:
+  bad_typeid() _NOEXCEPT : exception("bad typeid") {}
+
+private:
+  bad_typeid(const char* const __message) _NOEXCEPT : exception(__message) {}
+};
+
+} // namespace std
+
+#endif // defined(_LIBCPP_ABI_VCRUNTIME) && _HAS_EXCEPTIONS == 0
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+_LIBCPP_NORETURN inline _LIBCPP_INLINE_VISIBILITY void __throw_bad_cast() {
+#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+  throw bad_cast();
+#else
+  _LIBCPP_VERBOSE_ABORT("bad_cast was thrown in -fno-exceptions mode");
+#endif
+}
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPEINFO_TYPEINFO_H
diff --git a/libcxx/include/module.modulemap.in b/libcxx/include/module.modulemap.in
index 6d9bb8653fcb5e9..0752a7b133886e5 100644
--- a/libcxx/include/module.modulemap.in
+++ b/libcxx/include/module.modulemap.in
@@ -1274,6 +1274,8 @@ module std_private_debug_utils_strict_weak_ordering_check [system] {
   export std_private_type_traits_is_constant_evaluated
 }
 
+module std_private_typeinfo_typeinfo          [system] { header "__typeinfo/typeinfo.h" }
+
 module std_private_exception_exception        [system] { header "__exception/exception.h" }
 module std_private_exception_exception_ptr    [system] {
   header "__exception/exception_ptr.h"
diff --git a/libcxx/include/typeinfo b/libcxx/include/typeinfo
index 59bc291454c3d90..61872a1510b313d 100644
--- a/libcxx/include/typeinfo
+++ b/libcxx/include/typeinfo
@@ -57,18 +57,15 @@ public:
 */
 
 #include <__assert> // all public C++ headers provide the assertion handler
-#include <__availability>
 #include <__config>
-#include <__exception/exception.h>
-#include <__type_traits/is_constant_evaluated.h>
-#include <__verbose_abort>
-#include <cstddef>
-#include <cstdint>
+#include <__typeinfo/typeinfo.h>
+#include <version>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
 
+<<<<<<< HEAD
 #if defined(_LIBCPP_ABI_VCRUNTIME)
 #include <vcruntime_typeinfo.h>
 #else
diff --git a/libcxx/src/support/runtime/exception_pointer_cxxabi.ipp b/libcxx/src/support/runtime/exception_pointer_cxxabi.ipp
index 277c5b867f679a8..f8ad08c11b736b9 100644
--- a/libcxx/src/support/runtime/exception_pointer_cxxabi.ipp
+++ b/libcxx/src/support/runtime/exception_pointer_cxxabi.ipp
@@ -13,8 +13,9 @@
 
 namespace std {
 
-exception_ptr::~exception_ptr() noexcept {
-  __cxa_decrement_exception_refcount(__ptr_);
+exception_ptr::~exception_ptr() noexcept
+{
+    __cxa_decrement_exception_refcount(__ptr_);
 }
 
 exception_ptr::exception_ptr(const exception_ptr& other) noexcept
@@ -34,17 +35,19 @@ exception_ptr& exception_ptr::operator=(const exception_ptr& other) noexcept
     return *this;
 }
 
-void *exception_ptr::init_ex(size_t size, type_info *tinfo, void (*dest)(void *)) noexcept {
-  void *__ex = __cxa_allocate_exception(size);
-  (void)__cxa_init_primary_exception(__ex, tinfo, dest);
-  return __ex;
+void *exception_ptr::__init_native_exception(size_t size, type_info *tinfo, void (*dest)(void *)) noexcept 
+{
+    void *__ex = __cxa_allocate_exception(size);
+    (void)__cxa_init_primary_exception(__ex, tinfo, dest);
+    return __ex;
 }
 
-void exception_ptr::free_ex(void *thrown_object) noexcept {
-  __cxa_free_exception(thrown_object);
+void exception_ptr::__free_native_exception(void *thrown_object) noexcept
+{
+    __cxa_free_exception(thrown_object);
 }
 
-exception_ptr exception_ptr::from_ex_ptr(void *__e) noexcept {
+exception_ptr exception_ptr::__from_native_exception_pointer(void *__e) noexcept {
     exception_ptr ptr;
     ptr.__ptr_ = __e;
     __cxa_increment_exception_refcount(ptr.__ptr_);

>From 34085c6cadbd7b327374d58a17c2a86c65d49459 Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Wed, 23 Aug 2023 22:37:40 +0300
Subject: [PATCH 04/14] + clang-format, fix libcxx.imp

---
 libcxx/include/__typeinfo/typeinfo.h | 2 +-
 libcxx/include/libcxx.imp            | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/libcxx/include/__typeinfo/typeinfo.h b/libcxx/include/__typeinfo/typeinfo.h
index 64b50711bbfd4e4..ac3550be0842e54 100644
--- a/libcxx/include/__typeinfo/typeinfo.h
+++ b/libcxx/include/__typeinfo/typeinfo.h
@@ -294,7 +294,7 @@ class _LIBCPP_EXPORTED_FROM_ABI bad_typeid : public exception {
 
 } // namespace std
 
-#endif   // defined(_LIBCPP_ABI_VCRUNTIME)
+#endif // defined(_LIBCPP_ABI_VCRUNTIME)
 
 #if defined(_LIBCPP_ABI_VCRUNTIME) && _HAS_EXCEPTIONS == 0
 
diff --git a/libcxx/include/libcxx.imp b/libcxx/include/libcxx.imp
index 3eb2aa849314824..f7e906e024f33a4 100644
--- a/libcxx/include/libcxx.imp
+++ b/libcxx/include/libcxx.imp
@@ -48,6 +48,7 @@
   { include: [ "@<__thread/.*>", "private", "<thread>", "public" ] },
   { include: [ "@<__tuple/.*>", "private", "<tuple>", "public" ] },
   { include: [ "@<__type_traits/.*>", "private", "<type_traits>", "public" ] },
+  { include: [ "@<__typeinfo/.*>", "private", "<typeinfo>", "public" ] },
   { include: [ "@<__utility/.*>", "private", "<utility>", "public" ] },
   { include: [ "@<__variant/.*>", "private", "<variant>", "public" ] },
 ]

>From 96525b409db24e8ea6fa0be9d8906c59f37e18f2 Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Tue, 29 Aug 2023 14:36:53 +0300
Subject: [PATCH 05/14] wip on making the build green

---
 libcxx/include/CMakeLists.txt       | 2 +-
 libcxx/utils/data/ignore_format.txt | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index 484efde56a82e32..eb189e90960d9d0 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -694,7 +694,6 @@ set(files
   __tuple/tuple_like_ext.h
   __tuple/tuple_size.h
   __tuple/tuple_types.h
-  __typeinfo/typeinfo.h
   __type_traits/add_const.h
   __type_traits/add_cv.h
   __type_traits/add_lvalue_reference.h
@@ -833,6 +832,7 @@ set(files
   __type_traits/underlying_type.h
   __type_traits/unwrap_ref.h
   __type_traits/void_t.h
+  __typeinfo/typeinfo.h
   __undef_macros
   __utility/as_const.h
   __utility/auto_cast.h
diff --git a/libcxx/utils/data/ignore_format.txt b/libcxx/utils/data/ignore_format.txt
index cbb7837897f3e12..c0fe756b26b309a 100644
--- a/libcxx/utils/data/ignore_format.txt
+++ b/libcxx/utils/data/ignore_format.txt
@@ -465,6 +465,7 @@ libcxx/include/__tuple/tuple_indices.h
 libcxx/include/__tuple/tuple_like_ext.h
 libcxx/include/__tuple/tuple_size.h
 libcxx/include/__tuple/tuple_types.h
+libcxx/include/__typeinfo/typeinfo.h
 libcxx/include/typeindex
 libcxx/include/typeinfo
 libcxx/include/uchar.h

>From c8426e4b0edeaa8cce4b7c568a11384731a85e6c Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Tue, 29 Aug 2023 19:25:34 +0300
Subject: [PATCH 06/14] wip on making the build green

---
 libcxx/include/module.modulemap.in               | 5 ++++-
 libcxx/include/typeinfo                          | 1 -
 libcxx/test/libcxx/transitive_includes/cxx03.csv | 1 +
 libcxx/test/libcxx/transitive_includes/cxx11.csv | 1 +
 libcxx/test/libcxx/transitive_includes/cxx14.csv | 1 +
 libcxx/test/libcxx/transitive_includes/cxx17.csv | 1 +
 libcxx/test/libcxx/transitive_includes/cxx20.csv | 1 +
 libcxx/test/libcxx/transitive_includes/cxx23.csv | 3 +++
 libcxx/test/libcxx/transitive_includes/cxx26.csv | 3 +++
 9 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/libcxx/include/module.modulemap.in b/libcxx/include/module.modulemap.in
index 0752a7b133886e5..11362014a543b95 100644
--- a/libcxx/include/module.modulemap.in
+++ b/libcxx/include/module.modulemap.in
@@ -1274,7 +1274,10 @@ module std_private_debug_utils_strict_weak_ordering_check [system] {
   export std_private_type_traits_is_constant_evaluated
 }
 
-module std_private_typeinfo_typeinfo          [system] { header "__typeinfo/typeinfo.h" }
+module std_private_typeinfo_typeinfo          [system] { 
+  header "__typeinfo/typeinfo.h" 
+  export *
+}
 
 module std_private_exception_exception        [system] { header "__exception/exception.h" }
 module std_private_exception_exception_ptr    [system] {
diff --git a/libcxx/include/typeinfo b/libcxx/include/typeinfo
index 61872a1510b313d..3a9087f7752fc17 100644
--- a/libcxx/include/typeinfo
+++ b/libcxx/include/typeinfo
@@ -59,7 +59,6 @@ public:
 #include <__assert> // all public C++ headers provide the assertion handler
 #include <__config>
 #include <__typeinfo/typeinfo.h>
-#include <version>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
diff --git a/libcxx/test/libcxx/transitive_includes/cxx03.csv b/libcxx/test/libcxx/transitive_includes/cxx03.csv
index 57420b9a3795d41..910bad3ce94adc7 100644
--- a/libcxx/test/libcxx/transitive_includes/cxx03.csv
+++ b/libcxx/test/libcxx/transitive_includes/cxx03.csv
@@ -219,6 +219,7 @@ deque type_traits
 deque typeinfo
 deque version
 exception cstddef
+exception cstdint
 exception cstdlib
 exception type_traits
 exception version
diff --git a/libcxx/test/libcxx/transitive_includes/cxx11.csv b/libcxx/test/libcxx/transitive_includes/cxx11.csv
index 464c0ef892c6195..f28206d02038b1b 100644
--- a/libcxx/test/libcxx/transitive_includes/cxx11.csv
+++ b/libcxx/test/libcxx/transitive_includes/cxx11.csv
@@ -220,6 +220,7 @@ deque type_traits
 deque typeinfo
 deque version
 exception cstddef
+exception cstdint
 exception cstdlib
 exception type_traits
 exception version
diff --git a/libcxx/test/libcxx/transitive_includes/cxx14.csv b/libcxx/test/libcxx/transitive_includes/cxx14.csv
index eb698e29d922ddc..65df2be5374afcd 100644
--- a/libcxx/test/libcxx/transitive_includes/cxx14.csv
+++ b/libcxx/test/libcxx/transitive_includes/cxx14.csv
@@ -220,6 +220,7 @@ deque type_traits
 deque typeinfo
 deque version
 exception cstddef
+exception cstdint
 exception cstdlib
 exception type_traits
 exception version
diff --git a/libcxx/test/libcxx/transitive_includes/cxx17.csv b/libcxx/test/libcxx/transitive_includes/cxx17.csv
index eb698e29d922ddc..65df2be5374afcd 100644
--- a/libcxx/test/libcxx/transitive_includes/cxx17.csv
+++ b/libcxx/test/libcxx/transitive_includes/cxx17.csv
@@ -220,6 +220,7 @@ deque type_traits
 deque typeinfo
 deque version
 exception cstddef
+exception cstdint
 exception cstdlib
 exception type_traits
 exception version
diff --git a/libcxx/test/libcxx/transitive_includes/cxx20.csv b/libcxx/test/libcxx/transitive_includes/cxx20.csv
index 9ba59c10734b3ec..1a6d73fc06b2cf5 100644
--- a/libcxx/test/libcxx/transitive_includes/cxx20.csv
+++ b/libcxx/test/libcxx/transitive_includes/cxx20.csv
@@ -226,6 +226,7 @@ deque type_traits
 deque typeinfo
 deque version
 exception cstddef
+exception cstdint
 exception cstdlib
 exception type_traits
 exception version
diff --git a/libcxx/test/libcxx/transitive_includes/cxx23.csv b/libcxx/test/libcxx/transitive_includes/cxx23.csv
index baaf19a002b0eb1..e18ec62e01a2ab0 100644
--- a/libcxx/test/libcxx/transitive_includes/cxx23.csv
+++ b/libcxx/test/libcxx/transitive_includes/cxx23.csv
@@ -153,7 +153,9 @@ deque stdexcept
 deque tuple
 deque version
 exception cstddef
+exception cstdint
 exception cstdlib
+exception type_traits
 exception version
 execution cstddef
 execution version
@@ -285,6 +287,7 @@ future ratio
 future stdexcept
 future string
 future thread
+future type_traits
 future typeinfo
 future version
 initializer_list cstddef
diff --git a/libcxx/test/libcxx/transitive_includes/cxx26.csv b/libcxx/test/libcxx/transitive_includes/cxx26.csv
index baaf19a002b0eb1..e18ec62e01a2ab0 100644
--- a/libcxx/test/libcxx/transitive_includes/cxx26.csv
+++ b/libcxx/test/libcxx/transitive_includes/cxx26.csv
@@ -153,7 +153,9 @@ deque stdexcept
 deque tuple
 deque version
 exception cstddef
+exception cstdint
 exception cstdlib
+exception type_traits
 exception version
 execution cstddef
 execution version
@@ -285,6 +287,7 @@ future ratio
 future stdexcept
 future string
 future thread
+future type_traits
 future typeinfo
 future version
 initializer_list cstddef

>From b7c2bdb7e8df5a3b93afd64c0a6b7ec20619258a Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Wed, 30 Aug 2023 11:48:05 +0300
Subject: [PATCH 07/14] regenerate ignore_format.txt

---
 libcxx/utils/data/ignore_format.txt | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/libcxx/utils/data/ignore_format.txt b/libcxx/utils/data/ignore_format.txt
index c0fe756b26b309a..2a4a4fca7d16fe8 100644
--- a/libcxx/utils/data/ignore_format.txt
+++ b/libcxx/utils/data/ignore_format.txt
@@ -123,6 +123,7 @@ libcxx/include/__chrono/literals.h
 libcxx/include/__chrono/monthday.h
 libcxx/include/__chrono/month.h
 libcxx/include/__chrono/month_weekday.h
+libcxx/include/__chrono/statically_widen.h
 libcxx/include/__chrono/steady_clock.h
 libcxx/include/__chrono/system_clock.h
 libcxx/include/__chrono/time_point.h
@@ -145,7 +146,9 @@ libcxx/include/__compare/strong_order.h
 libcxx/include/__compare/three_way_comparable.h
 libcxx/include/__compare/weak_order.h
 libcxx/include/complex
+libcxx/include/__concepts/swappable.h
 libcxx/include/condition_variable
+libcxx/include/__config
 libcxx/include/__coroutine/coroutine_handle.h
 libcxx/include/__coroutine/coroutine_traits.h
 libcxx/include/__coroutine/noop_coroutine_handle.h
@@ -156,8 +159,10 @@ libcxx/include/cuchar
 libcxx/include/__debug_utils/randomize_range.h
 libcxx/include/deque
 libcxx/include/errno.h
+libcxx/include/__exception/exception_ptr.h
 libcxx/include/expected
 libcxx/include/__expected/expected.h
+libcxx/include/__expected/unexpected.h
 libcxx/include/experimental/__config
 libcxx/include/experimental/iterator
 libcxx/include/experimental/map
@@ -333,6 +338,7 @@ libcxx/include/mutex
 libcxx/include/new
 libcxx/include/__node_handle
 libcxx/include/numbers
+libcxx/include/numeric
 libcxx/include/__numeric/accumulate.h
 libcxx/include/__numeric/adjacent_difference.h
 libcxx/include/__numeric/exclusive_scan.h
@@ -348,6 +354,7 @@ libcxx/include/__numeric/transform_inclusive_scan.h
 libcxx/include/__numeric/transform_reduce.h
 libcxx/include/optional
 libcxx/include/ostream
+libcxx/include/print
 libcxx/include/queue
 libcxx/include/__random/bernoulli_distribution.h
 libcxx/include/__random/binomial_distribution.h
@@ -411,6 +418,7 @@ libcxx/include/__ranges/single_view.h
 libcxx/include/__ranges/size.h
 libcxx/include/__ranges/subrange.h
 libcxx/include/__ranges/take_view.h
+libcxx/include/__ranges/to.h
 libcxx/include/__ranges/transform_view.h
 libcxx/include/__ranges/view_interface.h
 libcxx/include/__ranges/views.h
@@ -449,8 +457,12 @@ libcxx/include/__support/newlib/xlocale.h
 libcxx/include/__support/win32/locale_win32.h
 libcxx/include/__support/xlocale/__nop_locale_mgmt.h
 libcxx/include/__system_error/errc.h
+libcxx/include/__system_error/error_category.h
+libcxx/include/__system_error/error_code.h
+libcxx/include/__system_error/error_condition.h
 libcxx/include/thread
 libcxx/include/__thread/formatter.h
+libcxx/include/__thread/id.h
 libcxx/include/__threading_support
 libcxx/include/__thread/poll_with_backoff.h
 libcxx/include/__thread/this_thread.h
@@ -465,9 +477,12 @@ libcxx/include/__tuple/tuple_indices.h
 libcxx/include/__tuple/tuple_like_ext.h
 libcxx/include/__tuple/tuple_size.h
 libcxx/include/__tuple/tuple_types.h
-libcxx/include/__typeinfo/typeinfo.h
 libcxx/include/typeindex
-libcxx/include/typeinfo
+libcxx/include/__typeinfo/typeinfo.h
+libcxx/include/type_traits
+libcxx/include/__type_traits/is_nothrow_copy_constructible.h
+libcxx/include/__type_traits/is_nothrow_move_constructible.h
+libcxx/include/__type_traits/promote.h
 libcxx/include/uchar.h
 libcxx/include/unordered_map
 libcxx/include/unordered_set
@@ -481,6 +496,7 @@ libcxx/include/__utility/pair.h
 libcxx/include/__utility/piecewise_construct.h
 libcxx/include/__utility/priority_tag.h
 libcxx/include/__utility/rel_ops.h
+libcxx/include/__utility/terminate_on_exception.h
 libcxx/include/__utility/to_underlying.h
 libcxx/include/__utility/unreachable.h
 libcxx/include/valarray
@@ -530,6 +546,7 @@ libcxx/src/mutex.cpp
 libcxx/src/mutex_destructor.cpp
 libcxx/src/new.cpp
 libcxx/src/optional.cpp
+libcxx/src/print.cpp
 libcxx/src/pstl/libdispatch.cpp
 libcxx/src/random.cpp
 libcxx/src/random_shuffle.cpp

>From 2cc6b1202fc75d12aeafafb8def7f7925edb98c8 Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Wed, 30 Aug 2023 13:13:14 +0300
Subject: [PATCH 08/14] bits of formatting

---
 libcxx/include/module.modulemap.in            |  4 ++--
 .../runtime/exception_pointer_cxxabi.ipp      |  2 +-
 libcxx/utils/data/ignore_format.txt           | 20 +------------------
 3 files changed, 4 insertions(+), 22 deletions(-)

diff --git a/libcxx/include/module.modulemap.in b/libcxx/include/module.modulemap.in
index 11362014a543b95..c8ea9ff9cad2ff6 100644
--- a/libcxx/include/module.modulemap.in
+++ b/libcxx/include/module.modulemap.in
@@ -1274,8 +1274,8 @@ module std_private_debug_utils_strict_weak_ordering_check [system] {
   export std_private_type_traits_is_constant_evaluated
 }
 
-module std_private_typeinfo_typeinfo          [system] { 
-  header "__typeinfo/typeinfo.h" 
+module std_private_typeinfo_typeinfo          [system] {
+  header "__typeinfo/typeinfo.h"
   export *
 }
 
diff --git a/libcxx/src/support/runtime/exception_pointer_cxxabi.ipp b/libcxx/src/support/runtime/exception_pointer_cxxabi.ipp
index f8ad08c11b736b9..93e08dba3cd9bd5 100644
--- a/libcxx/src/support/runtime/exception_pointer_cxxabi.ipp
+++ b/libcxx/src/support/runtime/exception_pointer_cxxabi.ipp
@@ -35,7 +35,7 @@ exception_ptr& exception_ptr::operator=(const exception_ptr& other) noexcept
     return *this;
 }
 
-void *exception_ptr::__init_native_exception(size_t size, type_info *tinfo, void (*dest)(void *)) noexcept 
+void *exception_ptr::__init_native_exception(size_t size, type_info *tinfo, void (*dest)(void *)) noexcept
 {
     void *__ex = __cxa_allocate_exception(size);
     (void)__cxa_init_primary_exception(__ex, tinfo, dest);
diff --git a/libcxx/utils/data/ignore_format.txt b/libcxx/utils/data/ignore_format.txt
index 2a4a4fca7d16fe8..cbb7837897f3e12 100644
--- a/libcxx/utils/data/ignore_format.txt
+++ b/libcxx/utils/data/ignore_format.txt
@@ -123,7 +123,6 @@ libcxx/include/__chrono/literals.h
 libcxx/include/__chrono/monthday.h
 libcxx/include/__chrono/month.h
 libcxx/include/__chrono/month_weekday.h
-libcxx/include/__chrono/statically_widen.h
 libcxx/include/__chrono/steady_clock.h
 libcxx/include/__chrono/system_clock.h
 libcxx/include/__chrono/time_point.h
@@ -146,9 +145,7 @@ libcxx/include/__compare/strong_order.h
 libcxx/include/__compare/three_way_comparable.h
 libcxx/include/__compare/weak_order.h
 libcxx/include/complex
-libcxx/include/__concepts/swappable.h
 libcxx/include/condition_variable
-libcxx/include/__config
 libcxx/include/__coroutine/coroutine_handle.h
 libcxx/include/__coroutine/coroutine_traits.h
 libcxx/include/__coroutine/noop_coroutine_handle.h
@@ -159,10 +156,8 @@ libcxx/include/cuchar
 libcxx/include/__debug_utils/randomize_range.h
 libcxx/include/deque
 libcxx/include/errno.h
-libcxx/include/__exception/exception_ptr.h
 libcxx/include/expected
 libcxx/include/__expected/expected.h
-libcxx/include/__expected/unexpected.h
 libcxx/include/experimental/__config
 libcxx/include/experimental/iterator
 libcxx/include/experimental/map
@@ -338,7 +333,6 @@ libcxx/include/mutex
 libcxx/include/new
 libcxx/include/__node_handle
 libcxx/include/numbers
-libcxx/include/numeric
 libcxx/include/__numeric/accumulate.h
 libcxx/include/__numeric/adjacent_difference.h
 libcxx/include/__numeric/exclusive_scan.h
@@ -354,7 +348,6 @@ libcxx/include/__numeric/transform_inclusive_scan.h
 libcxx/include/__numeric/transform_reduce.h
 libcxx/include/optional
 libcxx/include/ostream
-libcxx/include/print
 libcxx/include/queue
 libcxx/include/__random/bernoulli_distribution.h
 libcxx/include/__random/binomial_distribution.h
@@ -418,7 +411,6 @@ libcxx/include/__ranges/single_view.h
 libcxx/include/__ranges/size.h
 libcxx/include/__ranges/subrange.h
 libcxx/include/__ranges/take_view.h
-libcxx/include/__ranges/to.h
 libcxx/include/__ranges/transform_view.h
 libcxx/include/__ranges/view_interface.h
 libcxx/include/__ranges/views.h
@@ -457,12 +449,8 @@ libcxx/include/__support/newlib/xlocale.h
 libcxx/include/__support/win32/locale_win32.h
 libcxx/include/__support/xlocale/__nop_locale_mgmt.h
 libcxx/include/__system_error/errc.h
-libcxx/include/__system_error/error_category.h
-libcxx/include/__system_error/error_code.h
-libcxx/include/__system_error/error_condition.h
 libcxx/include/thread
 libcxx/include/__thread/formatter.h
-libcxx/include/__thread/id.h
 libcxx/include/__threading_support
 libcxx/include/__thread/poll_with_backoff.h
 libcxx/include/__thread/this_thread.h
@@ -478,11 +466,7 @@ libcxx/include/__tuple/tuple_like_ext.h
 libcxx/include/__tuple/tuple_size.h
 libcxx/include/__tuple/tuple_types.h
 libcxx/include/typeindex
-libcxx/include/__typeinfo/typeinfo.h
-libcxx/include/type_traits
-libcxx/include/__type_traits/is_nothrow_copy_constructible.h
-libcxx/include/__type_traits/is_nothrow_move_constructible.h
-libcxx/include/__type_traits/promote.h
+libcxx/include/typeinfo
 libcxx/include/uchar.h
 libcxx/include/unordered_map
 libcxx/include/unordered_set
@@ -496,7 +480,6 @@ libcxx/include/__utility/pair.h
 libcxx/include/__utility/piecewise_construct.h
 libcxx/include/__utility/priority_tag.h
 libcxx/include/__utility/rel_ops.h
-libcxx/include/__utility/terminate_on_exception.h
 libcxx/include/__utility/to_underlying.h
 libcxx/include/__utility/unreachable.h
 libcxx/include/valarray
@@ -546,7 +529,6 @@ libcxx/src/mutex.cpp
 libcxx/src/mutex_destructor.cpp
 libcxx/src/new.cpp
 libcxx/src/optional.cpp
-libcxx/src/print.cpp
 libcxx/src/pstl/libdispatch.cpp
 libcxx/src/random.cpp
 libcxx/src/random_shuffle.cpp

>From cb2c374abdb16c3cd8ac20fdde4a3cad96c6f7be Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Wed, 30 Aug 2023 14:42:45 +0300
Subject: [PATCH 09/14] wip on making the build green

---
 libcxx/utils/data/ignore_format.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libcxx/utils/data/ignore_format.txt b/libcxx/utils/data/ignore_format.txt
index cbb7837897f3e12..c5f7598b906ca81 100644
--- a/libcxx/utils/data/ignore_format.txt
+++ b/libcxx/utils/data/ignore_format.txt
@@ -465,8 +465,8 @@ libcxx/include/__tuple/tuple_indices.h
 libcxx/include/__tuple/tuple_like_ext.h
 libcxx/include/__tuple/tuple_size.h
 libcxx/include/__tuple/tuple_types.h
+libcxx/include/__typeinfo/typeinfo.h
 libcxx/include/typeindex
-libcxx/include/typeinfo
 libcxx/include/uchar.h
 libcxx/include/unordered_map
 libcxx/include/unordered_set

>From ed954d3a585495bf18b7c455b4875b51df8f6c84 Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Wed, 30 Aug 2023 16:37:23 +0300
Subject: [PATCH 10/14] wip on making the build green

---
 libcxx/utils/data/ignore_format.txt | 1 -
 1 file changed, 1 deletion(-)

diff --git a/libcxx/utils/data/ignore_format.txt b/libcxx/utils/data/ignore_format.txt
index c5f7598b906ca81..74592cd8c16ba13 100644
--- a/libcxx/utils/data/ignore_format.txt
+++ b/libcxx/utils/data/ignore_format.txt
@@ -465,7 +465,6 @@ libcxx/include/__tuple/tuple_indices.h
 libcxx/include/__tuple/tuple_like_ext.h
 libcxx/include/__tuple/tuple_size.h
 libcxx/include/__tuple/tuple_types.h
-libcxx/include/__typeinfo/typeinfo.h
 libcxx/include/typeindex
 libcxx/include/uchar.h
 libcxx/include/unordered_map

>From 786f1f458eeff154011567f9a8a8dd12ef1c4573 Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Thu, 7 Sep 2023 00:25:28 +0300
Subject: [PATCH 11/14] ABI fixes

---
 libcxx/include/__exception/exception_ptr.h | 6 +++---
 libcxxabi/lib/exceptions.exp               | 1 +
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index 0e5310c767cbe92..bcb84d8bc06e59e 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -34,9 +34,9 @@ class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
     static_cast<_Ep*>(__x)->~_Ep();
   }
 
-  static void* __init_native_exception(size_t, std::type_info*, void (*)(void*)) _NOEXCEPT;
-  static void __free_native_exception(void*) _NOEXCEPT;
-  static exception_ptr __from_native_exception_pointer(void* __e) _NOEXCEPT;
+  _LIBCPP_HIDE_FROM_ABI static void* __init_native_exception(size_t, std::type_info*, void (*)(void*)) _NOEXCEPT;
+  _LIBCPP_HIDE_FROM_ABI static void __free_native_exception(void*) _NOEXCEPT;
+  _LIBCPP_HIDE_FROM_ABI static exception_ptr __from_native_exception_pointer(void* __e) _NOEXCEPT;
 
   template <class _Ep>
   friend _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep) _NOEXCEPT;
diff --git a/libcxxabi/lib/exceptions.exp b/libcxxabi/lib/exceptions.exp
index c3780d2974903ce..9dcfbdbd3598e12 100644
--- a/libcxxabi/lib/exceptions.exp
+++ b/libcxxabi/lib/exceptions.exp
@@ -7,5 +7,6 @@ ___cxa_end_catch
 ___cxa_free_dependent_exception
 ___cxa_free_exception
 ___cxa_get_exception_ptr
+___cxa_init_primary_exception
 ___cxa_rethrow
 ___cxa_throw

>From f06631b7932088f7a4b59a4202a1b27b6ecbb4b3 Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Mon, 25 Sep 2023 16:46:25 +0300
Subject: [PATCH 12/14] rebase fix

---
 libcxx/include/typeinfo | 348 ----------------------------------------
 1 file changed, 348 deletions(-)

diff --git a/libcxx/include/typeinfo b/libcxx/include/typeinfo
index 3a9087f7752fc17..e869cd5e6750787 100644
--- a/libcxx/include/typeinfo
+++ b/libcxx/include/typeinfo
@@ -64,354 +64,6 @@ public:
 #  pragma GCC system_header
 #endif
 
-<<<<<<< HEAD
-#if defined(_LIBCPP_ABI_VCRUNTIME)
-#include <vcruntime_typeinfo.h>
-#else
-
-namespace std  // purposefully not using versioning namespace
-{
-
-
-#if defined(_LIBCPP_ABI_MICROSOFT)
-
-class _LIBCPP_EXPORTED_FROM_ABI type_info
-{
-    type_info& operator=(const type_info&);
-    type_info(const type_info&);
-
-    mutable struct {
-      const char *__undecorated_name;
-      const char __decorated_name[1];
-    } __data;
-
-    int __compare(const type_info &__rhs) const _NOEXCEPT;
-
-public:
-    _LIBCPP_AVAILABILITY_TYPEINFO_VTABLE
-    virtual ~type_info();
-
-    const char *name() const _NOEXCEPT;
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool before(const type_info& __arg) const _NOEXCEPT {
-      return __compare(__arg) < 0;
-    }
-
-    size_t hash_code() const _NOEXCEPT;
-
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23
-    bool operator==(const type_info& __arg) const _NOEXCEPT {
-      // When evaluated in a constant expression, both type infos simply can't come
-      // from different translation units, so it is sufficient to compare their addresses.
-      if (__libcpp_is_constant_evaluated()) {
-        return this == &__arg;
-      }
-      return __compare(__arg) == 0;
-    }
-
-#if _LIBCPP_STD_VER <= 17
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator!=(const type_info& __arg) const _NOEXCEPT
-    { return !operator==(__arg); }
-#endif
-};
-
-#else // !defined(_LIBCPP_ABI_MICROSOFT)
-
-// ========================================================================== //
-//                           Implementations
-// ========================================================================== //
-// ------------------------------------------------------------------------- //
-//                               Unique
-//               (_LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION = 1)
-// ------------------------------------------------------------------------- //
-// This implementation of type_info assumes a unique copy of the RTTI for a
-// given type inside a program. This is a valid assumption when abiding to the
-// Itanium ABI (http://itanium-cxx-abi.github.io/cxx-abi/abi.html#vtable-components).
-// Under this assumption, we can always compare the addresses of the type names
-// to implement equality-comparison of type_infos instead of having to perform
-// a deep string comparison.
-// -------------------------------------------------------------------------- //
-//                             NonUnique
-//               (_LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION = 2)
-// -------------------------------------------------------------------------- //
-// This implementation of type_info does not assume there is always a unique
-// copy of the RTTI for a given type inside a program. For various reasons
-// the linker may have failed to merge every copy of a types RTTI
-// (For example: -Bsymbolic or llvm.org/PR37398). Under this assumption, two
-// type_infos are equal if their addresses are equal or if a deep string
-// comparison is equal.
-// -------------------------------------------------------------------------- //
-//                          NonUniqueARMRTTIBit
-//               (_LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION = 3)
-// -------------------------------------------------------------------------- //
-// This implementation is specific to ARM64 on Apple platforms.
-//
-// This implementation of type_info does not assume always a unique copy of
-// the RTTI for a given type inside a program. When constructing the type_info,
-// the compiler packs the pointer to the type name into a uintptr_t and reserves
-// the high bit of that pointer, which is assumed to be free for use under that
-// ABI. If that high bit is set, that specific copy of the RTTI can't be assumed
-// to be unique within the program. If the high bit is unset, then the RTTI can
-// be assumed to be unique within the program.
-//
-// When comparing type_infos, if both RTTIs can be assumed to be unique, it
-// suffices to compare their addresses. If both the RTTIs can't be assumed to
-// be unique, we must perform a deep string comparison of the type names.
-// However, if one of the RTTIs is guaranteed unique and the other one isn't,
-// then both RTTIs are necessarily not to be considered equal.
-//
-// The intent of this design is to remove the need for weak symbols. Specifically,
-// if a type would normally have a default-visibility RTTI emitted as a weak
-// symbol, it is given hidden visibility instead and the non-unique bit is set.
-// Otherwise, types declared with hidden visibility are always considered to have
-// a unique RTTI: the RTTI is emitted with linkonce_odr linkage and is assumed
-// to be deduplicated by the linker within the linked image. Across linked image
-// boundaries, such types are thus considered different types.
-
-// This value can be overriden in the __config_site. When it's not overriden,
-// we pick a default implementation based on the platform here.
-#ifndef _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION
-
-  // Windows and AIX binaries can't merge typeinfos, so use the NonUnique implementation.
-# if defined(_LIBCPP_OBJECT_FORMAT_COFF) || defined(_LIBCPP_OBJECT_FORMAT_XCOFF)
-#   define _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION 2
-
-  // On arm64 on Apple platforms, use the special NonUniqueARMRTTIBit implementation.
-# elif defined(__APPLE__) && defined(__LP64__) && !defined(__x86_64__)
-#   define _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION 3
-
-  // On all other platforms, assume the Itanium C++ ABI and use the Unique implementation.
-# else
-#   define _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION 1
-# endif
-#endif
-
-struct __type_info_implementations {
-  struct __string_impl_base {
-    typedef const char* __type_name_t;
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    _LIBCPP_CONSTEXPR static const char* __type_name_to_string(__type_name_t __v) _NOEXCEPT {
-      return __v;
-    }
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    _LIBCPP_CONSTEXPR static __type_name_t __string_to_type_name(const char* __v) _NOEXCEPT {
-      return __v;
-    }
-  };
-
-  struct __unique_impl : __string_impl_base {
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    static size_t __hash(__type_name_t __v) _NOEXCEPT {
-      return reinterpret_cast<size_t>(__v);
-    }
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    static bool __eq(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
-      return __lhs == __rhs;
-    }
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    static bool __lt(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
-      return __lhs < __rhs;
-    }
-  };
-
-  struct __non_unique_impl : __string_impl_base {
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    static size_t __hash(__type_name_t __ptr) _NOEXCEPT {
-      size_t __hash = 5381;
-      while (unsigned char __c = static_cast<unsigned char>(*__ptr++))
-        __hash = (__hash * 33) ^ __c;
-      return __hash;
-    }
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    static bool __eq(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
-      return __lhs == __rhs || __builtin_strcmp(__lhs, __rhs) == 0;
-    }
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    static bool __lt(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
-      return __builtin_strcmp(__lhs, __rhs) < 0;
-    }
-  };
-
-  struct __non_unique_arm_rtti_bit_impl {
-    typedef uintptr_t __type_name_t;
-
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    static const char* __type_name_to_string(__type_name_t __v) _NOEXCEPT {
-      return reinterpret_cast<const char*>(__v &
-          ~__non_unique_rtti_bit::value);
-    }
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    static __type_name_t __string_to_type_name(const char* __v) _NOEXCEPT {
-      return reinterpret_cast<__type_name_t>(__v);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    static size_t __hash(__type_name_t __v) _NOEXCEPT {
-      if (__is_type_name_unique(__v))
-        return __v;
-      return __non_unique_impl::__hash(__type_name_to_string(__v));
-    }
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    static bool __eq(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
-      if (__lhs == __rhs)
-        return true;
-      if (__is_type_name_unique(__lhs) || __is_type_name_unique(__rhs))
-        // Either both are unique and have a different address, or one of them
-        // is unique and the other one isn't. In both cases they are unequal.
-        return false;
-      return __builtin_strcmp(__type_name_to_string(__lhs), __type_name_to_string(__rhs)) == 0;
-    }
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_ALWAYS_INLINE
-    static bool __lt(__type_name_t __lhs, __type_name_t __rhs) _NOEXCEPT {
-      if (__is_type_name_unique(__lhs) || __is_type_name_unique(__rhs))
-        return __lhs < __rhs;
-      return __builtin_strcmp(__type_name_to_string(__lhs), __type_name_to_string(__rhs)) < 0;
-    }
-
-   private:
-    // The unique bit is the top bit. It is expected that __type_name_t is 64 bits when
-    // this implementation is actually used.
-    typedef integral_constant<__type_name_t,
-      (1ULL << ((__CHAR_BIT__ * sizeof(__type_name_t)) - 1))> __non_unique_rtti_bit;
-
-    _LIBCPP_INLINE_VISIBILITY
-    static bool __is_type_name_unique(__type_name_t __lhs) _NOEXCEPT {
-      return !(__lhs & __non_unique_rtti_bit::value);
-    }
-  };
-
-  typedef
-#if _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION == 1
-    __unique_impl
-#elif _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION == 2
-    __non_unique_impl
-#elif _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION == 3
-    __non_unique_arm_rtti_bit_impl
-#else
-#   error invalid configuration for _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION
-#endif
-     __impl;
-};
-
-class _LIBCPP_EXPORTED_FROM_ABI type_info
-{
-  type_info& operator=(const type_info&);
-  type_info(const type_info&);
-
- protected:
-    typedef __type_info_implementations::__impl __impl;
-
-    __impl::__type_name_t __type_name;
-
-    _LIBCPP_INLINE_VISIBILITY
-    explicit type_info(const char* __n)
-      : __type_name(__impl::__string_to_type_name(__n)) {}
-
-public:
-    _LIBCPP_AVAILABILITY_TYPEINFO_VTABLE
-    virtual ~type_info();
-
-    _LIBCPP_INLINE_VISIBILITY
-    const char* name() const _NOEXCEPT
-    {
-      return __impl::__type_name_to_string(__type_name);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool before(const type_info& __arg) const _NOEXCEPT
-    {
-      return __impl::__lt(__type_name, __arg.__type_name);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    size_t hash_code() const _NOEXCEPT
-    {
-      return __impl::__hash(__type_name);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX23
-    bool operator==(const type_info& __arg) const _NOEXCEPT
-    {
-      // When evaluated in a constant expression, both type infos simply can't come
-      // from different translation units, so it is sufficient to compare their addresses.
-      if (__libcpp_is_constant_evaluated()) {
-        return this == &__arg;
-      }
-      return __impl::__eq(__type_name, __arg.__type_name);
-    }
-
-#if _LIBCPP_STD_VER <= 17
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator!=(const type_info& __arg) const _NOEXCEPT
-    { return !operator==(__arg); }
-#endif
-};
-#endif // defined(_LIBCPP_ABI_MICROSOFT)
-
-class _LIBCPP_EXPORTED_FROM_ABI bad_cast
-    : public exception
-{
- public:
-  bad_cast() _NOEXCEPT;
-  _LIBCPP_HIDE_FROM_ABI bad_cast(const bad_cast&) _NOEXCEPT = default;
-  _LIBCPP_HIDE_FROM_ABI bad_cast& operator=(const bad_cast&) _NOEXCEPT = default;
-  ~bad_cast() _NOEXCEPT override;
-  const char* what() const _NOEXCEPT override;
-};
-
-class _LIBCPP_EXPORTED_FROM_ABI bad_typeid
-    : public exception
-{
- public:
-  bad_typeid() _NOEXCEPT;
-  _LIBCPP_HIDE_FROM_ABI bad_typeid(const bad_typeid&) _NOEXCEPT = default;
-  _LIBCPP_HIDE_FROM_ABI bad_typeid& operator=(const bad_typeid&) _NOEXCEPT = default;
-  ~bad_typeid() _NOEXCEPT override;
-  const char* what() const _NOEXCEPT override;
-};
-
-} // namespace std
-
-#endif // defined(_LIBCPP_ABI_VCRUNTIME)
-
-#if defined(_LIBCPP_ABI_VCRUNTIME) && _HAS_EXCEPTIONS == 0
-
-namespace std {
-
-class bad_cast : public exception {
-public:
-  bad_cast() _NOEXCEPT : exception("bad cast") {}
-
-private:
-  bad_cast(const char* const __message) _NOEXCEPT : exception(__message) {}
-};
-
-class bad_typeid : public exception {
-public:
-  bad_typeid() _NOEXCEPT : exception("bad typeid") {}
-
-private:
-  bad_typeid(const char* const __message) _NOEXCEPT : exception(__message) {}
-};
-
-} // namespace std
-
-#endif // defined(_LIBCPP_ABI_VCRUNTIME) && _HAS_EXCEPTIONS == 0
-
-_LIBCPP_BEGIN_NAMESPACE_STD
-_LIBCPP_NORETURN inline _LIBCPP_INLINE_VISIBILITY
-void __throw_bad_cast()
-{
-#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
-    throw bad_cast();
-#else
-    _LIBCPP_VERBOSE_ABORT("bad_cast was thrown in -fno-exceptions mode");
-#endif
-}
-_LIBCPP_END_NAMESPACE_STD
-
 #if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
 #  include <cstdlib>
 #  include <exception>

>From f33e88f891ece2b7e2ac8926f9845f990e0a8ee2 Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Wed, 27 Sep 2023 17:25:23 +0300
Subject: [PATCH 13/14] rebase fix

---
 libcxx/include/__typeinfo/typeinfo.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libcxx/include/__typeinfo/typeinfo.h b/libcxx/include/__typeinfo/typeinfo.h
index ac3550be0842e54..394cac5967870aa 100644
--- a/libcxx/include/__typeinfo/typeinfo.h
+++ b/libcxx/include/__typeinfo/typeinfo.h
@@ -281,6 +281,7 @@ class _LIBCPP_EXPORTED_FROM_ABI bad_cast : public exception {
 public:
   bad_cast() _NOEXCEPT;
   _LIBCPP_HIDE_FROM_ABI bad_cast(const bad_cast&) _NOEXCEPT = default;
+  _LIBCPP_HIDE_FROM_ABI bad_cast& operator=(const bad_cast&) _NOEXCEPT = default;
   ~bad_cast() _NOEXCEPT override;
   const char* what() const _NOEXCEPT override;
 };
@@ -288,6 +289,8 @@ class _LIBCPP_EXPORTED_FROM_ABI bad_cast : public exception {
 class _LIBCPP_EXPORTED_FROM_ABI bad_typeid : public exception {
 public:
   bad_typeid() _NOEXCEPT;
+  _LIBCPP_HIDE_FROM_ABI bad_typeid(const bad_typeid&) _NOEXCEPT = default;
+  _LIBCPP_HIDE_FROM_ABI bad_typeid& operator=(const bad_typeid&) _NOEXCEPT = default;
   ~bad_typeid() _NOEXCEPT override;
   const char* what() const _NOEXCEPT override;
 };

>From db85197afff2869561add2c39d617c62d46fce0e Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Wed, 27 Sep 2023 18:05:49 +0300
Subject: [PATCH 14/14] + clang-format

---
 libcxx/include/__typeinfo/typeinfo.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libcxx/include/__typeinfo/typeinfo.h b/libcxx/include/__typeinfo/typeinfo.h
index 394cac5967870aa..07b53af2b478588 100644
--- a/libcxx/include/__typeinfo/typeinfo.h
+++ b/libcxx/include/__typeinfo/typeinfo.h
@@ -280,7 +280,7 @@ class _LIBCPP_EXPORTED_FROM_ABI type_info {
 class _LIBCPP_EXPORTED_FROM_ABI bad_cast : public exception {
 public:
   bad_cast() _NOEXCEPT;
-  _LIBCPP_HIDE_FROM_ABI bad_cast(const bad_cast&) _NOEXCEPT = default;
+  _LIBCPP_HIDE_FROM_ABI bad_cast(const bad_cast&) _NOEXCEPT            = default;
   _LIBCPP_HIDE_FROM_ABI bad_cast& operator=(const bad_cast&) _NOEXCEPT = default;
   ~bad_cast() _NOEXCEPT override;
   const char* what() const _NOEXCEPT override;
@@ -289,7 +289,7 @@ class _LIBCPP_EXPORTED_FROM_ABI bad_cast : public exception {
 class _LIBCPP_EXPORTED_FROM_ABI bad_typeid : public exception {
 public:
   bad_typeid() _NOEXCEPT;
-  _LIBCPP_HIDE_FROM_ABI bad_typeid(const bad_typeid&) _NOEXCEPT = default;
+  _LIBCPP_HIDE_FROM_ABI bad_typeid(const bad_typeid&) _NOEXCEPT            = default;
   _LIBCPP_HIDE_FROM_ABI bad_typeid& operator=(const bad_typeid&) _NOEXCEPT = default;
   ~bad_typeid() _NOEXCEPT override;
   const char* what() const _NOEXCEPT override;



More information about the libcxx-commits mailing list