path: root/contrib/libs/cxxsupp/libcxx/patches/53-exception_pointer_msvc.patch

diff --git a/src/support/runtime/exception_pointer_msvc.ipp b/src/support/runtime/exception_pointer_msvc.ipp
index 9e7f392..c88c68c 100644
--- a/src/support/runtime/exception_pointer_msvc.ipp
+++ b/src/support/runtime/exception_pointer_msvc.ipp
@@ -7,70 +7,242 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include <stdio.h>
-#include <stdlib.h>
-
-_LIBCPP_CRT_FUNC void __cdecl __ExceptionPtrCreate(void*);
-_LIBCPP_CRT_FUNC void __cdecl __ExceptionPtrDestroy(void*);
-_LIBCPP_CRT_FUNC void __cdecl __ExceptionPtrCopy(void*, const void*);
-_LIBCPP_CRT_FUNC void __cdecl __ExceptionPtrAssign(void*, const void*);
-_LIBCPP_CRT_FUNC bool __cdecl __ExceptionPtrCompare(const void*, const void*);
-_LIBCPP_CRT_FUNC bool __cdecl __ExceptionPtrToBool(const void*);
-_LIBCPP_CRT_FUNC void __cdecl __ExceptionPtrSwap(void*, void*);
-_LIBCPP_CRT_FUNC void __cdecl __ExceptionPtrCurrentException(void*);
-[[noreturn]] _LIBCPP_CRT_FUNC void __cdecl __ExceptionPtrRethrow(const void*);
-_LIBCPP_CRT_FUNC void __cdecl
-__ExceptionPtrCopyException(void*, const void*, const void*);
+#include <atomic>
+#include <cstdint>
+#include <cstring>
+#include <malloc.h>
+#include <windows.h> // For RtlPcToFileHeader function
 
-namespace std {
+struct EHCatchableType {
+  uint32_t properties;
+  int32_t type_info;
+  uint32_t non_virtual_adjustment;
+  uint32_t offset_to_virtual_base_ptr;
+  uint32_t virtual_base_table_index;
+  uint32_t size;
+  int32_t copy_function;
+};
 
-exception_ptr::exception_ptr() noexcept { __ExceptionPtrCreate(this); }
-exception_ptr::exception_ptr(nullptr_t) noexcept { __ExceptionPtrCreate(this); }
+struct EHCatchableTypeArray {
+  uint32_t catchable_types;
+  // It is variable size but we only need the first element of this array
+  int32_t array_of_catchable_types[1];
+};
 
-exception_ptr::exception_ptr(const exception_ptr& __other) noexcept {
-  __ExceptionPtrCopy(this, &__other);
-}
-exception_ptr& exception_ptr::operator=(const exception_ptr& __other) noexcept {
-  __ExceptionPtrAssign(this, &__other);
-  return *this;
-}
+struct EHThrowInfo {
+  uint32_t attributes;
+  int32_t unwind;
+  int32_t forward_compat;
+  int32_t catchable_type_array;
+};
 
-exception_ptr& exception_ptr::operator=(nullptr_t) noexcept {
-  exception_ptr dummy;
-  __ExceptionPtrAssign(this, &dummy);
-  return *this;
-}
+struct EHParameters {
+  uint32_t magic_number;
+  void* exception_object;
+  EHThrowInfo* throw_info;
+#ifdef _M_AMD64
+  uintptr_t throw_image_base;
+#endif
+};
 
-exception_ptr::~exception_ptr() noexcept { __ExceptionPtrDestroy(this); }
+struct EHExceptionRecord {
+  uint32_t exception_code;
+  uint32_t exception_flags;
+  void* exception_record;
+  void* exception_address;
+  uint32_t number_of_parameters;
+  EHParameters parameters;
+};
 
-exception_ptr::operator bool() const noexcept {
-  return __ExceptionPtrToBool(this);
-}
+// defined in vcruntime<ver>.dll
+extern "C" EHExceptionRecord** __current_exception();
+
+// This is internal compiler definition for MSVC but not for clang.
+// We use our own EHThrowInfo because _ThrowInfo doesn't match actual
+// compiler-generated structures in 64-bit mode.
+#ifdef __clang__
+struct _ThrowInfo;
+// defined in vcruntime<ver>.dll
+extern "C" _LIBCPP_NORETURN void __stdcall _CxxThrowException(
+    void* __exc, _ThrowInfo* __throw_info);
+#endif
+
+namespace {
+struct ExceptionPtr {
+  void* exception_object;
+  const EHThrowInfo* throw_info;
+  std::atomic<size_t> counter;
+#ifdef _M_AMD64
+  PVOID image_base;
+#endif
+  template <class T>
+  T convert(int32_t offset) {
+#ifdef _M_AMD64
+    uintptr_t value = reinterpret_cast<uintptr_t>(image_base) +
+                      static_cast<uintptr_t>(offset);
+#else
+    uintptr_t value = static_cast<uintptr_t>(offset);
+#endif
+    T res;
+    static_assert(
+        sizeof(value) == sizeof(res),
+        "Can only convert to pointers or pointers to member functions");
+    memcpy(&res, &value, sizeof(value));
+    return res;
+  }
+
+  void copy(void* dst, const void* src, const EHCatchableType* exc_type) {
+    struct Temp {};
+    constexpr uint32_t virtual_base = 4;
+    if (exc_type->copy_function == 0) {
+      memcpy(dst, src, exc_type->size);
+    } else if (exc_type->properties & virtual_base) {
+      auto copy_constructor =
+          convert<void (Temp::*)(const void*, int)>(exc_type->copy_function);
+      ((Temp*)dst->*copy_constructor)(src, 1);
+    } else {
+      auto copy_constructor =
+          convert<void (Temp::*)(const void*)>(exc_type->copy_function);
+      ((Temp*)dst->*copy_constructor)(src);
+    }
+  }
+
+  EHCatchableType* exception_type() {
+    return convert<EHCatchableType*>(
+        convert<EHCatchableTypeArray*>(throw_info->catchable_type_array)
+            ->array_of_catchable_types[0]);
+  }
+
+  ExceptionPtr(const void* exception_object_, const EHThrowInfo* throw_info_)
+      : exception_object(nullptr), throw_info(throw_info_), counter(1) {
+#ifdef _M_AMD64
+    RtlPcToFileHeader(
+        reinterpret_cast<PVOID>(const_cast<EHThrowInfo*>(throw_info)),
+        &image_base);
+#endif
+    EHCatchableType* exc_type = exception_type();
+    this->exception_object = malloc(exc_type->size);
+    if (this->exception_object == nullptr) {
+      throw std::bad_alloc();
+    }
+    copy(exception_object, exception_object_, exc_type);
+  }
+
+  ~ExceptionPtr() {
+    if (throw_info->unwind && exception_object) {
+      struct Temp {};
+      auto destructor = convert<void (Temp::*)()>(throw_info->unwind);
+      ((Temp*)exception_object->*destructor)();
+    }
+    free(exception_object);
+  }
 
-bool operator==(const exception_ptr& __x, const exception_ptr& __y) noexcept {
-  return __ExceptionPtrCompare(&__x, &__y);
+  // _bad_alloc_storage must be initialized before bad_alloc, so we declare and define it first.
+  static std::bad_alloc _bad_alloc_storage;
+  static ExceptionPtr bad_alloc;
+  //static ExceptionPtr bad_exception;
+};
+
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Waddress-of-temporary"
+#endif
+
+std::bad_alloc ExceptionPtr::_bad_alloc_storage;
+
+ExceptionPtr ExceptionPtr::bad_alloc(
+    &ExceptionPtr::_bad_alloc_storage,
+    reinterpret_cast<const EHThrowInfo*>(__GetExceptionInfo(ExceptionPtr::_bad_alloc_storage)));
+
+/* ExceptionPtr
+ExceptionPtr::bad_exception(&std::bad_exception(),
+                            reinterpret_cast<const EHThrowInfo*>(
+                                __GetExceptionInfo(std::bad_exception()))); */
+
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+} // namespace
+
+namespace std {
+
+exception_ptr::exception_ptr(const exception_ptr& __other) noexcept
+    : __ptr_(__other.__ptr_) {
+  if (__ptr_) {
+    reinterpret_cast<ExceptionPtr*>(__ptr_)->counter.fetch_add(1);
+  }
 }
 
+exception_ptr& exception_ptr::
+operator=(const exception_ptr& __other) noexcept {
+  auto before = __ptr_;
+  __ptr_ = __other.__ptr_;
+  if (__ptr_) {
+    reinterpret_cast<ExceptionPtr*>(__ptr_)->counter.fetch_add(1);
+  }
+  if (before) {
+    if (reinterpret_cast<ExceptionPtr*>(before)->counter.fetch_sub(1) == 1) {
+      delete reinterpret_cast<ExceptionPtr*>(before);
+    }
+  }
+  return *this;
+}
 
-void swap(exception_ptr& lhs, exception_ptr& rhs) noexcept {
-  __ExceptionPtrSwap(&rhs, &lhs);
+exception_ptr::~exception_ptr() noexcept {
+  if (__ptr_) {
+    if (reinterpret_cast<ExceptionPtr*>(__ptr_)->counter.fetch_sub(1) == 1) {
+      delete reinterpret_cast<ExceptionPtr*>(__ptr_);
+    }
+  }
 }
 
-exception_ptr __copy_exception_ptr(void* __except, const void* __ptr) {
-  exception_ptr __ret = nullptr;
-  if (__ptr)
-    __ExceptionPtrCopyException(&__ret, __except, __ptr);
-  return __ret;
+exception_ptr __copy_exception_ptr(void* exception_object,
+                                   const void* throw_info) {
+  ExceptionPtr* ptr;
+  try {
+    ptr = new ExceptionPtr(exception_object,
+                           reinterpret_cast<const EHThrowInfo*>(throw_info));
+  } catch (const std::bad_alloc&) {
+    ptr = &ExceptionPtr::bad_alloc;
+    ptr->counter.fetch_add(1);
+  } catch (...) {
+    //ptr = &ExceptionPtr::bad_exception;
+    //ptr->counter.fetch_add(1);
+    std::terminate();
+  }
+  exception_ptr res;
+  memcpy(&res, &ptr, sizeof(ptr));
+  return res;
 }
 
 exception_ptr current_exception() noexcept {
-  exception_ptr __ret;
-  __ExceptionPtrCurrentException(&__ret);
-  return __ret;
+  EHExceptionRecord** record = __current_exception();
+  if (*record && !std::uncaught_exception()) {
+    return __copy_exception_ptr((*record)->parameters.exception_object,
+                                (*record)->parameters.throw_info);
+  }
+  return exception_ptr();
 }
 
 _LIBCPP_NORETURN
-void rethrow_exception(exception_ptr p) { __ExceptionPtrRethrow(&p); }
+void rethrow_exception(exception_ptr p) {
+  if (!p) {
+    throw std::bad_exception();
+  }
+  ExceptionPtr* exc_ptr = reinterpret_cast<ExceptionPtr*>(p.__ptr_);
+  EHCatchableType* exc_type = exc_ptr->exception_type();
+  // _CxxThrowException doesn't call free on exception object so we must
+  // allocate it on the stack.
+  void* dst = _alloca(exc_type->size);
+  exc_ptr->copy(dst, exc_ptr->exception_object, exc_type);
+  auto throw_info = reinterpret_cast<_ThrowInfo*>(
+      const_cast<EHThrowInfo*>(exc_ptr->throw_info));
+  // For some reason clang doesn't call p destructor during unwinding.
+  // So we must clear it ourselves.
+  p = nullptr;
+  _CxxThrowException(dst, throw_info);
+}
 
 nested_exception::nested_exception() noexcept : __ptr_(current_exception()) {}