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diff --git a/clang-r353983/include/llvm/MC/MCAsmLayout.h b/clang-r353983/include/llvm/MC/MCAsmLayout.h
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+//===- MCAsmLayout.h - Assembly Layout Object -------------------*- 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 LLVM_MC_MCASMLAYOUT_H
+#define LLVM_MC_MCASMLAYOUT_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallVector.h"
+
+namespace llvm {
+class MCAssembler;
+class MCFragment;
+class MCSection;
+class MCSymbol;
+
+/// Encapsulates the layout of an assembly file at a particular point in time.
+///
+/// Assembly may require computing multiple layouts for a particular assembly
+/// file as part of the relaxation process. This class encapsulates the layout
+/// at a single point in time in such a way that it is always possible to
+/// efficiently compute the exact address of any symbol in the assembly file,
+/// even during the relaxation process.
+class MCAsmLayout {
+  MCAssembler &Assembler;
+
+  /// List of sections in layout order.
+  llvm::SmallVector<MCSection *, 16> SectionOrder;
+
+  /// The last fragment which was laid out, or 0 if nothing has been laid
+  /// out. Fragments are always laid out in order, so all fragments with a
+  /// lower ordinal will be valid.
+  mutable DenseMap<const MCSection *, MCFragment *> LastValidFragment;
+
+  /// Make sure that the layout for the given fragment is valid, lazily
+  /// computing it if necessary.
+  void ensureValid(const MCFragment *F) const;
+
+  /// Is the layout for this fragment valid?
+  bool isFragmentValid(const MCFragment *F) const;
+
+public:
+  MCAsmLayout(MCAssembler &Assembler);
+
+  /// Get the assembler object this is a layout for.
+  MCAssembler &getAssembler() const { return Assembler; }
+
+  /// Invalidate the fragments starting with F because it has been
+  /// resized. The fragment's size should have already been updated, but
+  /// its bundle padding will be recomputed.
+  void invalidateFragmentsFrom(MCFragment *F);
+
+  /// Perform layout for a single fragment, assuming that the previous
+  /// fragment has already been laid out correctly, and the parent section has
+  /// been initialized.
+  void layoutFragment(MCFragment *Fragment);
+
+  /// \name Section Access (in layout order)
+  /// @{
+
+  llvm::SmallVectorImpl<MCSection *> &getSectionOrder() { return SectionOrder; }
+  const llvm::SmallVectorImpl<MCSection *> &getSectionOrder() const {
+    return SectionOrder;
+  }
+
+  /// @}
+  /// \name Fragment Layout Data
+  /// @{
+
+  /// Get the offset of the given fragment inside its containing section.
+  uint64_t getFragmentOffset(const MCFragment *F) const;
+
+  /// @}
+  /// \name Utility Functions
+  /// @{
+
+  /// Get the address space size of the given section, as it effects
+  /// layout. This may differ from the size reported by \see getSectionSize() by
+  /// not including section tail padding.
+  uint64_t getSectionAddressSize(const MCSection *Sec) const;
+
+  /// Get the data size of the given section, as emitted to the object
+  /// file. This may include additional padding, or be 0 for virtual sections.
+  uint64_t getSectionFileSize(const MCSection *Sec) const;
+
+  /// Get the offset of the given symbol, as computed in the current
+  /// layout.
+  /// \return True on success.
+  bool getSymbolOffset(const MCSymbol &S, uint64_t &Val) const;
+
+  /// Variant that reports a fatal error if the offset is not computable.
+  uint64_t getSymbolOffset(const MCSymbol &S) const;
+
+  /// If this symbol is equivalent to A + Constant, return A.
+  const MCSymbol *getBaseSymbol(const MCSymbol &Symbol) const;
+
+  /// @}
+};
+
+} // end namespace llvm
+
+#endif