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diff --git a/contrib/llvm-project/clang/lib/CodeGen/CodeGenTBAA.h b/contrib/llvm-project/clang/lib/CodeGen/CodeGenTBAA.h
new file mode 100644
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+++ b/contrib/llvm-project/clang/lib/CodeGen/CodeGenTBAA.h
@@ -0,0 +1,257 @@
+//===--- CodeGenTBAA.h - TBAA information for LLVM CodeGen ------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This is the code that manages TBAA information and defines the TBAA policy
+// for the optimizer to use.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_CODEGEN_CODEGENTBAA_H
+#define LLVM_CLANG_LIB_CODEGEN_CODEGENTBAA_H
+
+#include "clang/AST/Type.h"
+#include "clang/Basic/LLVM.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/IR/MDBuilder.h"
+#include "llvm/IR/Metadata.h"
+
+namespace clang {
+  class ASTContext;
+  class CodeGenOptions;
+  class LangOptions;
+  class MangleContext;
+  class QualType;
+  class Type;
+
+namespace CodeGen {
+class CGRecordLayout;
+
+// TBAAAccessKind - A kind of TBAA memory access descriptor.
+enum class TBAAAccessKind : unsigned {
+  Ordinary,
+  MayAlias,
+  Incomplete,
+};
+
+// TBAAAccessInfo - Describes a memory access in terms of TBAA.
+struct TBAAAccessInfo {
+  TBAAAccessInfo(TBAAAccessKind Kind, llvm::MDNode *BaseType,
+                 llvm::MDNode *AccessType, uint64_t Offset, uint64_t Size)
+    : Kind(Kind), BaseType(BaseType), AccessType(AccessType),
+      Offset(Offset), Size(Size)
+  {}
+
+  TBAAAccessInfo(llvm::MDNode *BaseType, llvm::MDNode *AccessType,
+                 uint64_t Offset, uint64_t Size)
+    : TBAAAccessInfo(TBAAAccessKind::Ordinary, BaseType, AccessType,
+                     Offset, Size)
+  {}
+
+  explicit TBAAAccessInfo(llvm::MDNode *AccessType, uint64_t Size)
+    : TBAAAccessInfo(/* BaseType= */ nullptr, AccessType, /* Offset= */ 0, Size)
+  {}
+
+  TBAAAccessInfo()
+    : TBAAAccessInfo(/* AccessType= */ nullptr, /* Size= */ 0)
+  {}
+
+  static TBAAAccessInfo getMayAliasInfo() {
+    return TBAAAccessInfo(TBAAAccessKind::MayAlias,
+                          /* BaseType= */ nullptr, /* AccessType= */ nullptr,
+                          /* Offset= */ 0, /* Size= */ 0);
+  }
+
+  bool isMayAlias() const { return Kind == TBAAAccessKind::MayAlias; }
+
+  static TBAAAccessInfo getIncompleteInfo() {
+    return TBAAAccessInfo(TBAAAccessKind::Incomplete,
+                          /* BaseType= */ nullptr, /* AccessType= */ nullptr,
+                          /* Offset= */ 0, /* Size= */ 0);
+  }
+
+  bool isIncomplete() const { return Kind == TBAAAccessKind::Incomplete; }
+
+  bool operator==(const TBAAAccessInfo &Other) const {
+    return Kind == Other.Kind &&
+           BaseType == Other.BaseType &&
+           AccessType == Other.AccessType &&
+           Offset == Other.Offset &&
+           Size == Other.Size;
+  }
+
+  bool operator!=(const TBAAAccessInfo &Other) const {
+    return !(*this == Other);
+  }
+
+  explicit operator bool() const {
+    return *this != TBAAAccessInfo();
+  }
+
+  /// Kind - The kind of the access descriptor.
+  TBAAAccessKind Kind;
+
+  /// BaseType - The base/leading access type. May be null if this access
+  /// descriptor represents an access that is not considered to be an access
+  /// to an aggregate or union member.
+  llvm::MDNode *BaseType;
+
+  /// AccessType - The final access type. May be null if there is no TBAA
+  /// information available about this access.
+  llvm::MDNode *AccessType;
+
+  /// Offset - The byte offset of the final access within the base one. Must be
+  /// zero if the base access type is not specified.
+  uint64_t Offset;
+
+  /// Size - The size of access, in bytes.
+  uint64_t Size;
+};
+
+/// CodeGenTBAA - This class organizes the cross-module state that is used
+/// while lowering AST types to LLVM types.
+class CodeGenTBAA {
+  ASTContext &Context;
+  llvm::Module &Module;
+  const CodeGenOptions &CodeGenOpts;
+  const LangOptions &Features;
+  MangleContext &MContext;
+
+  // MDHelper - Helper for creating metadata.
+  llvm::MDBuilder MDHelper;
+
+  /// MetadataCache - This maps clang::Types to scalar llvm::MDNodes describing
+  /// them.
+  llvm::DenseMap<const Type *, llvm::MDNode *> MetadataCache;
+  /// This maps clang::Types to a base access type in the type DAG.
+  llvm::DenseMap<const Type *, llvm::MDNode *> BaseTypeMetadataCache;
+  /// This maps TBAA access descriptors to tag nodes.
+  llvm::DenseMap<TBAAAccessInfo, llvm::MDNode *> AccessTagMetadataCache;
+
+  /// StructMetadataCache - This maps clang::Types to llvm::MDNodes describing
+  /// them for struct assignments.
+  llvm::DenseMap<const Type *, llvm::MDNode *> StructMetadataCache;
+
+  llvm::MDNode *Root;
+  llvm::MDNode *Char;
+
+  /// getRoot - This is the mdnode for the root of the metadata type graph
+  /// for this translation unit.
+  llvm::MDNode *getRoot();
+
+  /// getChar - This is the mdnode for "char", which is special, and any types
+  /// considered to be equivalent to it.
+  llvm::MDNode *getChar();
+
+  /// CollectFields - Collect information about the fields of a type for
+  /// !tbaa.struct metadata formation. Return false for an unsupported type.
+  bool CollectFields(uint64_t BaseOffset,
+                     QualType Ty,
+                     SmallVectorImpl<llvm::MDBuilder::TBAAStructField> &Fields,
+                     bool MayAlias);
+
+  /// createScalarTypeNode - A wrapper function to create a metadata node
+  /// describing a scalar type.
+  llvm::MDNode *createScalarTypeNode(StringRef Name, llvm::MDNode *Parent,
+                                     uint64_t Size);
+
+  /// getTypeInfoHelper - An internal helper function to generate metadata used
+  /// to describe accesses to objects of the given type.
+  llvm::MDNode *getTypeInfoHelper(const Type *Ty);
+
+  /// getBaseTypeInfoHelper - An internal helper function to generate metadata
+  /// used to describe accesses to objects of the given base type.
+  llvm::MDNode *getBaseTypeInfoHelper(const Type *Ty);
+
+public:
+  CodeGenTBAA(ASTContext &Ctx, llvm::Module &M, const CodeGenOptions &CGO,
+              const LangOptions &Features, MangleContext &MContext);
+  ~CodeGenTBAA();
+
+  /// getTypeInfo - Get metadata used to describe accesses to objects of the
+  /// given type.
+  llvm::MDNode *getTypeInfo(QualType QTy);
+
+  /// getAccessInfo - Get TBAA information that describes an access to
+  /// an object of the given type.
+  TBAAAccessInfo getAccessInfo(QualType AccessType);
+
+  /// getVTablePtrAccessInfo - Get the TBAA information that describes an
+  /// access to a virtual table pointer.
+  TBAAAccessInfo getVTablePtrAccessInfo(llvm::Type *VTablePtrType);
+
+  /// getTBAAStructInfo - Get the TBAAStruct MDNode to be used for a memcpy of
+  /// the given type.
+  llvm::MDNode *getTBAAStructInfo(QualType QTy);
+
+  /// getBaseTypeInfo - Get metadata that describes the given base access type.
+  /// Return null if the type is not suitable for use in TBAA access tags.
+  llvm::MDNode *getBaseTypeInfo(QualType QTy);
+
+  /// getAccessTagInfo - Get TBAA tag for a given memory access.
+  llvm::MDNode *getAccessTagInfo(TBAAAccessInfo Info);
+
+  /// mergeTBAAInfoForCast - Get merged TBAA information for the purpose of
+  /// type casts.
+  TBAAAccessInfo mergeTBAAInfoForCast(TBAAAccessInfo SourceInfo,
+                                      TBAAAccessInfo TargetInfo);
+
+  /// mergeTBAAInfoForConditionalOperator - Get merged TBAA information for the
+  /// purpose of conditional operator.
+  TBAAAccessInfo mergeTBAAInfoForConditionalOperator(TBAAAccessInfo InfoA,
+                                                     TBAAAccessInfo InfoB);
+
+  /// mergeTBAAInfoForMemoryTransfer - Get merged TBAA information for the
+  /// purpose of memory transfer calls.
+  TBAAAccessInfo mergeTBAAInfoForMemoryTransfer(TBAAAccessInfo DestInfo,
+                                                TBAAAccessInfo SrcInfo);
+};
+
+}  // end namespace CodeGen
+}  // end namespace clang
+
+namespace llvm {
+
+template<> struct DenseMapInfo<clang::CodeGen::TBAAAccessInfo> {
+  static clang::CodeGen::TBAAAccessInfo getEmptyKey() {
+    unsigned UnsignedKey = DenseMapInfo<unsigned>::getEmptyKey();
+    return clang::CodeGen::TBAAAccessInfo(
+      static_cast<clang::CodeGen::TBAAAccessKind>(UnsignedKey),
+      DenseMapInfo<MDNode *>::getEmptyKey(),
+      DenseMapInfo<MDNode *>::getEmptyKey(),
+      DenseMapInfo<uint64_t>::getEmptyKey(),
+      DenseMapInfo<uint64_t>::getEmptyKey());
+  }
+
+  static clang::CodeGen::TBAAAccessInfo getTombstoneKey() {
+    unsigned UnsignedKey = DenseMapInfo<unsigned>::getTombstoneKey();
+    return clang::CodeGen::TBAAAccessInfo(
+      static_cast<clang::CodeGen::TBAAAccessKind>(UnsignedKey),
+      DenseMapInfo<MDNode *>::getTombstoneKey(),
+      DenseMapInfo<MDNode *>::getTombstoneKey(),
+      DenseMapInfo<uint64_t>::getTombstoneKey(),
+      DenseMapInfo<uint64_t>::getTombstoneKey());
+  }
+
+  static unsigned getHashValue(const clang::CodeGen::TBAAAccessInfo &Val) {
+    auto KindValue = static_cast<unsigned>(Val.Kind);
+    return DenseMapInfo<unsigned>::getHashValue(KindValue) ^
+           DenseMapInfo<MDNode *>::getHashValue(Val.BaseType) ^
+           DenseMapInfo<MDNode *>::getHashValue(Val.AccessType) ^
+           DenseMapInfo<uint64_t>::getHashValue(Val.Offset) ^
+           DenseMapInfo<uint64_t>::getHashValue(Val.Size);
+  }
+
+  static bool isEqual(const clang::CodeGen::TBAAAccessInfo &LHS,
+                      const clang::CodeGen::TBAAAccessInfo &RHS) {
+    return LHS == RHS;
+  }
+};
+
+}  // end namespace llvm
+
+#endif