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diff --git a/contrib/llvm-project/compiler-rt/lib/orc/error.h b/contrib/llvm-project/compiler-rt/lib/orc/error.h
new file mode 100644
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+++ b/contrib/llvm-project/compiler-rt/lib/orc/error.h
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+//===-------- error.h - Enforced error checking for ORC RT ------*- 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 ORC_RT_ERROR_H
+#define ORC_RT_ERROR_H
+
+#include "compiler.h"
+#include "extensible_rtti.h"
+#include "stl_extras.h"
+
+#include <cassert>
+#include <memory>
+#include <string>
+#include <type_traits>
+
+namespace __orc_rt {
+
+/// Base class for all errors.
+class ErrorInfoBase : public RTTIExtends<ErrorInfoBase, RTTIRoot> {
+public:
+  virtual std::string toString() const = 0;
+};
+
+/// Represents an environmental error.
+class ORC_RT_NODISCARD Error {
+
+  template <typename ErrT, typename... ArgTs>
+  friend Error make_error(ArgTs &&...Args);
+
+  friend Error repackage_error(std::unique_ptr<ErrorInfoBase>);
+
+  template <typename ErrT> friend std::unique_ptr<ErrT> error_cast(Error &);
+
+  template <typename T> friend class Expected;
+
+public:
+  /// Destroy this error. Aborts if error was not checked, or was checked but
+  /// not handled.
+  ~Error() { assertIsChecked(); }
+
+  Error(const Error &) = delete;
+  Error &operator=(const Error &) = delete;
+
+  /// Move-construct an error. The newly constructed error is considered
+  /// unchecked, even if the source error had been checked. The original error
+  /// becomes a checked success value.
+  Error(Error &&Other) {
+    setChecked(true);
+    *this = std::move(Other);
+  }
+
+  /// Move-assign an error value. The current error must represent success, you
+  /// you cannot overwrite an unhandled error. The current error is then
+  /// considered unchecked. The source error becomes a checked success value,
+  /// regardless of its original state.
+  Error &operator=(Error &&Other) {
+    // Don't allow overwriting of unchecked values.
+    assertIsChecked();
+    setPtr(Other.getPtr());
+
+    // This Error is unchecked, even if the source error was checked.
+    setChecked(false);
+
+    // Null out Other's payload and set its checked bit.
+    Other.setPtr(nullptr);
+    Other.setChecked(true);
+
+    return *this;
+  }
+
+  /// Create a success value.
+  static Error success() { return Error(); }
+
+  /// Error values convert to true for failure values, false otherwise.
+  explicit operator bool() {
+    setChecked(getPtr() == nullptr);
+    return getPtr() != nullptr;
+  }
+
+  /// Return true if this Error contains a failure value of the given type.
+  template <typename ErrT> bool isA() const {
+    return getPtr() && getPtr()->isA<ErrT>();
+  }
+
+private:
+  Error() = default;
+
+  Error(std::unique_ptr<ErrorInfoBase> ErrInfo) {
+    auto RawErrPtr = reinterpret_cast<uintptr_t>(ErrInfo.release());
+    assert((RawErrPtr & 0x1) == 0 && "ErrorInfo is insufficiently aligned");
+    ErrPtr = RawErrPtr | 0x1;
+  }
+
+  void assertIsChecked() {
+    if (ORC_RT_UNLIKELY(!isChecked() || getPtr())) {
+      fprintf(stderr, "Error must be checked prior to destruction.\n");
+      abort(); // Some sort of JIT program abort?
+    }
+  }
+
+  template <typename ErrT = ErrorInfoBase> ErrT *getPtr() const {
+    return reinterpret_cast<ErrT *>(ErrPtr & ~uintptr_t(1));
+  }
+
+  void setPtr(ErrorInfoBase *Ptr) {
+    ErrPtr = (reinterpret_cast<uintptr_t>(Ptr) & ~uintptr_t(1)) | (ErrPtr & 1);
+  }
+
+  bool isChecked() const { return ErrPtr & 0x1; }
+
+  void setChecked(bool Checked) { ErrPtr = (ErrPtr & ~uintptr_t(1)) | Checked; }
+
+  template <typename ErrT = ErrorInfoBase> std::unique_ptr<ErrT> takePayload() {
+    static_assert(std::is_base_of<ErrorInfoBase, ErrT>::value,
+                  "ErrT is not an ErrorInfoBase subclass");
+    std::unique_ptr<ErrT> Tmp(getPtr<ErrT>());
+    setPtr(nullptr);
+    setChecked(true);
+    return Tmp;
+  }
+
+  uintptr_t ErrPtr = 0;
+};
+
+/// Construct an error of ErrT with the given arguments.
+template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&...Args) {
+  static_assert(std::is_base_of<ErrorInfoBase, ErrT>::value,
+                "ErrT is not an ErrorInfoBase subclass");
+  return Error(std::make_unique<ErrT>(std::forward<ArgTs>(Args)...));
+}
+
+/// Construct an error of ErrT using a std::unique_ptr<ErrorInfoBase>. The
+/// primary use-case for this is 're-packaging' errors after inspecting them
+/// using error_cast, hence the name.
+inline Error repackage_error(std::unique_ptr<ErrorInfoBase> EIB) {
+  return Error(std::move(EIB));
+}
+
+/// If the argument is an error of type ErrT then this function unpacks it
+/// and returns a std::unique_ptr<ErrT>. Otherwise returns a nullptr and
+/// leaves the error untouched. Common usage looks like:
+///
+/// \code{.cpp}
+///   if (Error E = foo()) {
+///     if (auto EV1 = error_cast<ErrorType1>(E)) {
+///       // use unwrapped EV1 value.
+///     } else if (EV2 = error_cast<ErrorType2>(E)) {
+///       // use unwrapped EV2 value.
+///     } ...
+///   }
+/// \endcode
+template <typename ErrT> std::unique_ptr<ErrT> error_cast(Error &Err) {
+  static_assert(std::is_base_of<ErrorInfoBase, ErrT>::value,
+                "ErrT is not an ErrorInfoBase subclass");
+  if (Err.isA<ErrT>())
+    return Err.takePayload<ErrT>();
+  return nullptr;
+}
+
+/// Helper for Errors used as out-parameters.
+/// Sets the 'checked' flag on construction, resets it on destruction.
+class ErrorAsOutParameter {
+public:
+  ErrorAsOutParameter(Error *Err) : Err(Err) {
+    // Raise the checked bit if Err is success.
+    if (Err)
+      (void)!!*Err;
+  }
+
+  ~ErrorAsOutParameter() {
+    // Clear the checked bit.
+    if (Err && !*Err)
+      *Err = Error::success();
+  }
+
+private:
+  Error *Err;
+};
+
+template <typename T> class ORC_RT_NODISCARD Expected {
+
+  template <class OtherT> friend class Expected;
+
+  static constexpr bool IsRef = std::is_reference<T>::value;
+  using wrap = std::reference_wrapper<std::remove_reference_t<T>>;
+  using error_type = std::unique_ptr<ErrorInfoBase>;
+  using storage_type = std::conditional_t<IsRef, wrap, T>;
+  using value_type = T;
+
+  using reference = std::remove_reference_t<T> &;
+  using const_reference = const std::remove_reference_t<T> &;
+  using pointer = std::remove_reference_t<T> *;
+  using const_pointer = const std::remove_reference_t<T> *;
+
+public:
+  /// Create an Expected from a failure value.
+  Expected(Error Err) : HasError(true), Unchecked(true) {
+    assert(Err && "Cannot create Expected<T> from Error success value");
+    new (getErrorStorage()) error_type(Err.takePayload());
+  }
+
+  /// Create an Expected from a T value.
+  template <typename OtherT>
+  Expected(OtherT &&Val,
+           std::enable_if_t<std::is_convertible<OtherT, T>::value> * = nullptr)
+      : HasError(false), Unchecked(true) {
+    new (getStorage()) storage_type(std::forward<OtherT>(Val));
+  }
+
+  /// Move-construct an Expected<T> from an Expected<OtherT>.
+  Expected(Expected &&Other) { moveConstruct(std::move(Other)); }
+
+  /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
+  /// must be convertible to T.
+  template <class OtherT>
+  Expected(
+      Expected<OtherT> &&Other,
+      std::enable_if_t<std::is_convertible<OtherT, T>::value> * = nullptr) {
+    moveConstruct(std::move(Other));
+  }
+
+  /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
+  /// isn't convertible to T.
+  template <class OtherT>
+  explicit Expected(
+      Expected<OtherT> &&Other,
+      std::enable_if_t<!std::is_convertible<OtherT, T>::value> * = nullptr) {
+    moveConstruct(std::move(Other));
+  }
+
+  /// Move-assign from another Expected<T>.
+  Expected &operator=(Expected &&Other) {
+    moveAssign(std::move(Other));
+    return *this;
+  }
+
+  /// Destroy an Expected<T>.
+  ~Expected() {
+    assertIsChecked();
+    if (!HasError)
+      getStorage()->~storage_type();
+    else
+      getErrorStorage()->~error_type();
+  }
+
+  /// Returns true if this Expected value is in a success state (holding a T),
+  /// and false if this Expected value is in a failure state.
+  explicit operator bool() {
+    Unchecked = HasError;
+    return !HasError;
+  }
+
+  /// Returns true if this Expected value holds an Error of type error_type.
+  template <typename ErrT> bool isFailureOfType() const {
+    return HasError && (*getErrorStorage())->template isFailureOfType<ErrT>();
+  }
+
+  /// Take ownership of the stored error.
+  ///
+  /// If this Expected value is in a success state (holding a T) then this
+  /// method is a no-op and returns Error::success.
+  ///
+  /// If thsi Expected value is in a failure state (holding an Error) then this
+  /// method returns the contained error and leaves this Expected in an
+  /// 'empty' state from which it may be safely destructed but not otherwise
+  /// accessed.
+  Error takeError() {
+    Unchecked = false;
+    return HasError ? Error(std::move(*getErrorStorage())) : Error::success();
+  }
+
+  /// Returns a pointer to the stored T value.
+  pointer operator->() {
+    assertIsChecked();
+    return toPointer(getStorage());
+  }
+
+  /// Returns a pointer to the stored T value.
+  const_pointer operator->() const {
+    assertIsChecked();
+    return toPointer(getStorage());
+  }
+
+  /// Returns a reference to the stored T value.
+  reference operator*() {
+    assertIsChecked();
+    return *getStorage();
+  }
+
+  /// Returns a reference to the stored T value.
+  const_reference operator*() const {
+    assertIsChecked();
+    return *getStorage();
+  }
+
+private:
+  template <class T1>
+  static bool compareThisIfSameType(const T1 &a, const T1 &b) {
+    return &a == &b;
+  }
+
+  template <class T1, class T2>
+  static bool compareThisIfSameType(const T1 &a, const T2 &b) {
+    return false;
+  }
+
+  template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) {
+    HasError = Other.HasError;
+    Unchecked = true;
+    Other.Unchecked = false;
+
+    if (!HasError)
+      new (getStorage()) storage_type(std::move(*Other.getStorage()));
+    else
+      new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage()));
+  }
+
+  template <class OtherT> void moveAssign(Expected<OtherT> &&Other) {
+    assertIsChecked();
+
+    if (compareThisIfSameType(*this, Other))
+      return;
+
+    this->~Expected();
+    new (this) Expected(std::move(Other));
+  }
+
+  pointer toPointer(pointer Val) { return Val; }
+
+  const_pointer toPointer(const_pointer Val) const { return Val; }
+
+  pointer toPointer(wrap *Val) { return &Val->get(); }
+
+  const_pointer toPointer(const wrap *Val) const { return &Val->get(); }
+
+  storage_type *getStorage() {
+    assert(!HasError && "Cannot get value when an error exists!");
+    return reinterpret_cast<storage_type *>(&TStorage);
+  }
+
+  const storage_type *getStorage() const {
+    assert(!HasError && "Cannot get value when an error exists!");
+    return reinterpret_cast<const storage_type *>(&TStorage);
+  }
+
+  error_type *getErrorStorage() {
+    assert(HasError && "Cannot get error when a value exists!");
+    return reinterpret_cast<error_type *>(&ErrorStorage);
+  }
+
+  const error_type *getErrorStorage() const {
+    assert(HasError && "Cannot get error when a value exists!");
+    return reinterpret_cast<const error_type *>(&ErrorStorage);
+  }
+
+  void assertIsChecked() {
+    if (ORC_RT_UNLIKELY(Unchecked)) {
+      fprintf(stderr,
+              "Expected<T> must be checked before access or destruction.\n");
+      abort();
+    }
+  }
+
+  union {
+    std::aligned_union_t<1, storage_type> TStorage;
+    std::aligned_union_t<1, error_type> ErrorStorage;
+  };
+
+  bool HasError : 1;
+  bool Unchecked : 1;
+};
+
+/// Consume an error without doing anything.
+inline void consumeError(Error Err) {
+  if (Err)
+    (void)error_cast<ErrorInfoBase>(Err);
+}
+
+/// Consumes success values. It is a programmatic error to call this function
+/// on a failure value.
+inline void cantFail(Error Err) {
+  assert(!Err && "cantFail called on failure value");
+  consumeError(std::move(Err));
+}
+
+/// Auto-unwrap an Expected<T> value in the success state. It is a programmatic
+/// error to call this function on a failure value.
+template <typename T> T cantFail(Expected<T> E) {
+  assert(E && "cantFail called on failure value");
+  consumeError(E.takeError());
+  return std::move(*E);
+}
+
+/// Auto-unwrap an Expected<T> value in the success state. It is a programmatic
+/// error to call this function on a failure value.
+template <typename T> T &cantFail(Expected<T &> E) {
+  assert(E && "cantFail called on failure value");
+  consumeError(E.takeError());
+  return *E;
+}
+
+/// Convert the given error to a string. The error value is consumed in the
+/// process.
+inline std::string toString(Error Err) {
+  if (auto EIB = error_cast<ErrorInfoBase>(Err))
+    return EIB->toString();
+  return {};
+}
+
+class StringError : public RTTIExtends<StringError, ErrorInfoBase> {
+public:
+  StringError(std::string ErrMsg) : ErrMsg(std::move(ErrMsg)) {}
+  std::string toString() const override { return ErrMsg; }
+
+private:
+  std::string ErrMsg;
+};
+
+} // end namespace __orc_rt
+
+#endif // ORC_RT_ERROR_H