Import prebuilt clang toolchain for linux.
diff --git a/linux-x64/clang/include/llvm/MC/MCELFObjectWriter.h b/linux-x64/clang/include/llvm/MC/MCELFObjectWriter.h
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+++ b/linux-x64/clang/include/llvm/MC/MCELFObjectWriter.h
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+//===- llvm/MC/MCELFObjectWriter.h - ELF Object Writer ----------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_MCELFOBJECTWRITER_H
+#define LLVM_MC_MCELFOBJECTWRITER_H
+
+#include "llvm/ADT/Triple.h"
+#include "llvm/BinaryFormat/ELF.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/raw_ostream.h"
+#include <cstdint>
+#include <vector>
+
+namespace llvm {
+
+class MCAssembler;
+class MCContext;
+class MCFixup;
+class MCObjectWriter;
+class MCSymbol;
+class MCSymbolELF;
+class MCValue;
+
+struct ELFRelocationEntry {
+  uint64_t Offset; // Where is the relocation.
+  const MCSymbolELF *Symbol; // The symbol to relocate with.
+  unsigned Type;   // The type of the relocation.
+  uint64_t Addend; // The addend to use.
+  const MCSymbolELF *OriginalSymbol; // The original value of Symbol if we changed it.
+  uint64_t OriginalAddend; // The original value of addend.
+
+  ELFRelocationEntry(uint64_t Offset, const MCSymbolELF *Symbol, unsigned Type,
+                     uint64_t Addend, const MCSymbolELF *OriginalSymbol,
+                     uint64_t OriginalAddend)
+      : Offset(Offset), Symbol(Symbol), Type(Type), Addend(Addend),
+        OriginalSymbol(OriginalSymbol), OriginalAddend(OriginalAddend) {}
+
+  void print(raw_ostream &Out) const {
+    Out << "Off=" << Offset << ", Sym=" << Symbol << ", Type=" << Type
+        << ", Addend=" << Addend << ", OriginalSymbol=" << OriginalSymbol
+        << ", OriginalAddend=" << OriginalAddend;
+  }
+
+  void dump() const { print(errs()); }
+};
+
+class MCELFObjectTargetWriter {
+  const uint8_t OSABI;
+  const uint16_t EMachine;
+  const unsigned HasRelocationAddend : 1;
+  const unsigned Is64Bit : 1;
+
+protected:
+  MCELFObjectTargetWriter(bool Is64Bit_, uint8_t OSABI_, uint16_t EMachine_,
+                          bool HasRelocationAddend);
+
+public:
+  virtual ~MCELFObjectTargetWriter() = default;
+
+  static uint8_t getOSABI(Triple::OSType OSType) {
+    switch (OSType) {
+      case Triple::CloudABI:
+        return ELF::ELFOSABI_CLOUDABI;
+      case Triple::PS4:
+      case Triple::FreeBSD:
+        return ELF::ELFOSABI_FREEBSD;
+      default:
+        return ELF::ELFOSABI_NONE;
+    }
+  }
+
+  virtual unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
+                                const MCFixup &Fixup, bool IsPCRel) const = 0;
+
+  virtual bool needsRelocateWithSymbol(const MCSymbol &Sym,
+                                       unsigned Type) const;
+
+  virtual void sortRelocs(const MCAssembler &Asm,
+                          std::vector<ELFRelocationEntry> &Relocs);
+
+  /// \name Accessors
+  /// @{
+  uint8_t getOSABI() const { return OSABI; }
+  uint16_t getEMachine() const { return EMachine; }
+  bool hasRelocationAddend() const { return HasRelocationAddend; }
+  bool is64Bit() const { return Is64Bit; }
+  /// @}
+
+  // Instead of changing everyone's API we pack the N64 Type fields
+  // into the existing 32 bit data unsigned.
+#define R_TYPE_SHIFT 0
+#define R_TYPE_MASK 0xffffff00
+#define R_TYPE2_SHIFT 8
+#define R_TYPE2_MASK 0xffff00ff
+#define R_TYPE3_SHIFT 16
+#define R_TYPE3_MASK 0xff00ffff
+#define R_SSYM_SHIFT 24
+#define R_SSYM_MASK 0x00ffffff
+
+  // N64 relocation type accessors
+  uint8_t getRType(uint32_t Type) const {
+    return (unsigned)((Type >> R_TYPE_SHIFT) & 0xff);
+  }
+  uint8_t getRType2(uint32_t Type) const {
+    return (unsigned)((Type >> R_TYPE2_SHIFT) & 0xff);
+  }
+  uint8_t getRType3(uint32_t Type) const {
+    return (unsigned)((Type >> R_TYPE3_SHIFT) & 0xff);
+  }
+  uint8_t getRSsym(uint32_t Type) const {
+    return (unsigned)((Type >> R_SSYM_SHIFT) & 0xff);
+  }
+
+  // N64 relocation type setting
+  unsigned setRType(unsigned Value, unsigned Type) const {
+    return ((Type & R_TYPE_MASK) | ((Value & 0xff) << R_TYPE_SHIFT));
+  }
+  unsigned setRType2(unsigned Value, unsigned Type) const {
+    return (Type & R_TYPE2_MASK) | ((Value & 0xff) << R_TYPE2_SHIFT);
+  }
+  unsigned setRType3(unsigned Value, unsigned Type) const {
+    return (Type & R_TYPE3_MASK) | ((Value & 0xff) << R_TYPE3_SHIFT);
+  }
+  unsigned setRSsym(unsigned Value, unsigned Type) const {
+    return (Type & R_SSYM_MASK) | ((Value & 0xff) << R_SSYM_SHIFT);
+  }
+};
+
+/// \brief Construct a new ELF writer instance.
+///
+/// \param MOTW - The target specific ELF writer subclass.
+/// \param OS - The stream to write to.
+/// \returns The constructed object writer.
+std::unique_ptr<MCObjectWriter>
+createELFObjectWriter(std::unique_ptr<MCELFObjectTargetWriter> MOTW,
+                      raw_pwrite_stream &OS, bool IsLittleEndian);
+
+} // end namespace llvm
+
+#endif // LLVM_MC_MCELFOBJECTWRITER_H