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diff --git a/contrib/llvm-project/compiler-rt/lib/orc/extensible_rtti.h b/contrib/llvm-project/compiler-rt/lib/orc/extensible_rtti.h
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+//===------ extensible_rtti.h - Extensible RTTI 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
+//
+//===----------------------------------------------------------------------===//
+//
+// \file
+//
+// Provides an extensible RTTI mechanism, that can be used regardless of whether
+// the runtime is built with -frtti or not. This is predominantly used to
+// support error handling.
+//
+// The RTTIRoot class defines methods for comparing type ids. Implementations
+// of these methods can be injected into new classes using the RTTIExtends
+// class template.
+//
+// E.g.
+//
+//   @code{.cpp}
+//   class MyBaseClass : public RTTIExtends<MyBaseClass, RTTIRoot> {
+//   public:
+//     static char ID;
+//     virtual void foo() = 0;
+//   };
+//
+//   class MyDerivedClass1 : public RTTIExtends<MyDerivedClass1, MyBaseClass> {
+//   public:
+//     static char ID;
+//     void foo() override {}
+//   };
+//
+//   class MyDerivedClass2 : public RTTIExtends<MyDerivedClass2, MyBaseClass> {
+//   public:
+//     static char ID;
+//     void foo() override {}
+//   };
+//
+//   char MyBaseClass::ID = 0;
+//   char MyDerivedClass1::ID = 0;
+//   char MyDerivedClass2:: ID = 0;
+//
+//   void fn() {
+//     std::unique_ptr<MyBaseClass> B = std::make_unique<MyDerivedClass1>();
+//     outs() << isa<MyBaseClass>(B) << "\n"; // Outputs "1".
+//     outs() << isa<MyDerivedClass1>(B) << "\n"; // Outputs "1".
+//     outs() << isa<MyDerivedClass2>(B) << "\n"; // Outputs "0'.
+//   }
+//
+//   @endcode
+//
+// Note:
+//   This header was adapted from llvm/Support/ExtensibleRTTI.h, however the
+// data structures are not shared and the code need not be kept in sync.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef ORC_RT_EXTENSIBLE_RTTI_H
+#define ORC_RT_EXTENSIBLE_RTTI_H
+
+namespace __orc_rt {
+
+template <typename ThisT, typename ParentT> class RTTIExtends;
+
+/// Base class for the extensible RTTI hierarchy.
+///
+/// This class defines virtual methods, dynamicClassID and isA, that enable
+/// type comparisons.
+class RTTIRoot {
+public:
+  virtual ~RTTIRoot() = default;
+
+  /// Returns the class ID for this type.
+  static const void *classID() { return &ID; }
+
+  /// Returns the class ID for the dynamic type of this RTTIRoot instance.
+  virtual const void *dynamicClassID() const = 0;
+
+  /// Returns true if this class's ID matches the given class ID.
+  virtual bool isA(const void *const ClassID) const {
+    return ClassID == classID();
+  }
+
+  /// Check whether this instance is a subclass of QueryT.
+  template <typename QueryT> bool isA() const { return isA(QueryT::classID()); }
+
+  static bool classof(const RTTIRoot *R) { return R->isA<RTTIRoot>(); }
+
+private:
+  virtual void anchor();
+
+  static char ID;
+};
+
+/// Inheritance utility for extensible RTTI.
+///
+/// Supports single inheritance only: A class can only have one
+/// ExtensibleRTTI-parent (i.e. a parent for which the isa<> test will work),
+/// though it can have many non-ExtensibleRTTI parents.
+///
+/// RTTIExtents uses CRTP so the first template argument to RTTIExtends is the
+/// newly introduced type, and the *second* argument is the parent class.
+///
+/// class MyType : public RTTIExtends<MyType, RTTIRoot> {
+/// public:
+///   static char ID;
+/// };
+///
+/// class MyDerivedType : public RTTIExtends<MyDerivedType, MyType> {
+/// public:
+///   static char ID;
+/// };
+///
+template <typename ThisT, typename ParentT> class RTTIExtends : public ParentT {
+public:
+  // Inherit constructors and isA methods from ParentT.
+  using ParentT::isA;
+  using ParentT::ParentT;
+
+  static char ID;
+
+  static const void *classID() { return &ThisT::ID; }
+
+  const void *dynamicClassID() const override { return &ThisT::ID; }
+
+  bool isA(const void *const ClassID) const override {
+    return ClassID == classID() || ParentT::isA(ClassID);
+  }
+
+  static bool classof(const RTTIRoot *R) { return R->isA<ThisT>(); }
+};
+
+template <typename ThisT, typename ParentT>
+char RTTIExtends<ThisT, ParentT>::ID = 0;
+
+/// Returns true if the given value is an instance of the template type
+/// parameter.
+template <typename To, typename From> bool isa(const From &Value) {
+  return To::classof(&Value);
+}
+
+} // end namespace __orc_rt
+
+#endif // ORC_RT_EXTENSIBLE_RTTI_H