Import prebuilt clang toolchain for linux.
diff --git a/linux-x64/clang/include/llvm/MC/MCSubtargetInfo.h b/linux-x64/clang/include/llvm/MC/MCSubtargetInfo.h
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+//===- llvm/MC/MCSubtargetInfo.h - Subtarget Information --------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file describes the subtarget options of a Target machine.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_MCSUBTARGETINFO_H
+#define LLVM_MC_MCSUBTARGETINFO_H
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/MC/MCInstrItineraries.h"
+#include "llvm/MC/MCSchedule.h"
+#include "llvm/MC/SubtargetFeature.h"
+#include <algorithm>
+#include <cassert>
+#include <cstdint>
+#include <string>
+
+namespace llvm {
+
+class MachineInstr;
+class MCInst;
+
+//===----------------------------------------------------------------------===//
+///
+/// Generic base class for all target subtargets.
+///
+class MCSubtargetInfo {
+  Triple TargetTriple;
+  std::string CPU; // CPU being targeted.
+  ArrayRef<SubtargetFeatureKV> ProcFeatures;  // Processor feature list
+  ArrayRef<SubtargetFeatureKV> ProcDesc;  // Processor descriptions
+
+  // Scheduler machine model
+  const SubtargetInfoKV *ProcSchedModels;
+  const MCWriteProcResEntry *WriteProcResTable;
+  const MCWriteLatencyEntry *WriteLatencyTable;
+  const MCReadAdvanceEntry *ReadAdvanceTable;
+  const MCSchedModel *CPUSchedModel;
+
+  const InstrStage *Stages;            // Instruction itinerary stages
+  const unsigned *OperandCycles;       // Itinerary operand cycles
+  const unsigned *ForwardingPaths;
+  FeatureBitset FeatureBits;           // Feature bits for current CPU + FS
+
+public:
+  MCSubtargetInfo(const MCSubtargetInfo &) = default;
+  MCSubtargetInfo(const Triple &TT, StringRef CPU, StringRef FS,
+                  ArrayRef<SubtargetFeatureKV> PF,
+                  ArrayRef<SubtargetFeatureKV> PD,
+                  const SubtargetInfoKV *ProcSched,
+                  const MCWriteProcResEntry *WPR, const MCWriteLatencyEntry *WL,
+                  const MCReadAdvanceEntry *RA, const InstrStage *IS,
+                  const unsigned *OC, const unsigned *FP);
+  MCSubtargetInfo() = delete;
+  MCSubtargetInfo &operator=(const MCSubtargetInfo &) = delete;
+  MCSubtargetInfo &operator=(MCSubtargetInfo &&) = delete;
+  virtual ~MCSubtargetInfo() = default;
+
+  const Triple &getTargetTriple() const { return TargetTriple; }
+  StringRef getCPU() const { return CPU; }
+
+  const FeatureBitset& getFeatureBits() const { return FeatureBits; }
+  void setFeatureBits(const FeatureBitset &FeatureBits_) {
+    FeatureBits = FeatureBits_;
+  }
+
+  bool hasFeature(unsigned Feature) const {
+    return FeatureBits[Feature];
+  }
+
+protected:
+  /// Initialize the scheduling model and feature bits.
+  ///
+  /// FIXME: Find a way to stick this in the constructor, since it should only
+  /// be called during initialization.
+  void InitMCProcessorInfo(StringRef CPU, StringRef FS);
+
+public:
+  /// Set the features to the default for the given CPU with an appended feature
+  /// string.
+  void setDefaultFeatures(StringRef CPU, StringRef FS);
+
+  /// Toggle a feature and return the re-computed feature bits.
+  /// This version does not change the implied bits.
+  FeatureBitset ToggleFeature(uint64_t FB);
+
+  /// Toggle a feature and return the re-computed feature bits.
+  /// This version does not change the implied bits.
+  FeatureBitset ToggleFeature(const FeatureBitset& FB);
+
+  /// Toggle a set of features and return the re-computed feature bits.
+  /// This version will also change all implied bits.
+  FeatureBitset ToggleFeature(StringRef FS);
+
+  /// Apply a feature flag and return the re-computed feature bits, including
+  /// all feature bits implied by the flag.
+  FeatureBitset ApplyFeatureFlag(StringRef FS);
+
+  /// Check whether the subtarget features are enabled/disabled as per
+  /// the provided string, ignoring all other features.
+  bool checkFeatures(StringRef FS) const;
+
+  /// Get the machine model of a CPU.
+  const MCSchedModel &getSchedModelForCPU(StringRef CPU) const;
+
+  /// Get the machine model for this subtarget's CPU.
+  const MCSchedModel &getSchedModel() const { return *CPUSchedModel; }
+
+  /// Return an iterator at the first process resource consumed by the given
+  /// scheduling class.
+  const MCWriteProcResEntry *getWriteProcResBegin(
+    const MCSchedClassDesc *SC) const {
+    return &WriteProcResTable[SC->WriteProcResIdx];
+  }
+  const MCWriteProcResEntry *getWriteProcResEnd(
+    const MCSchedClassDesc *SC) const {
+    return getWriteProcResBegin(SC) + SC->NumWriteProcResEntries;
+  }
+
+  const MCWriteLatencyEntry *getWriteLatencyEntry(const MCSchedClassDesc *SC,
+                                                  unsigned DefIdx) const {
+    assert(DefIdx < SC->NumWriteLatencyEntries &&
+           "MachineModel does not specify a WriteResource for DefIdx");
+
+    return &WriteLatencyTable[SC->WriteLatencyIdx + DefIdx];
+  }
+
+  int getReadAdvanceCycles(const MCSchedClassDesc *SC, unsigned UseIdx,
+                           unsigned WriteResID) const {
+    // TODO: The number of read advance entries in a class can be significant
+    // (~50). Consider compressing the WriteID into a dense ID of those that are
+    // used by ReadAdvance and representing them as a bitset.
+    for (const MCReadAdvanceEntry *I = &ReadAdvanceTable[SC->ReadAdvanceIdx],
+           *E = I + SC->NumReadAdvanceEntries; I != E; ++I) {
+      if (I->UseIdx < UseIdx)
+        continue;
+      if (I->UseIdx > UseIdx)
+        break;
+      // Find the first WriteResIdx match, which has the highest cycle count.
+      if (!I->WriteResourceID || I->WriteResourceID == WriteResID) {
+        return I->Cycles;
+      }
+    }
+    return 0;
+  }
+
+  /// Get scheduling itinerary of a CPU.
+  InstrItineraryData getInstrItineraryForCPU(StringRef CPU) const;
+
+  /// Initialize an InstrItineraryData instance.
+  void initInstrItins(InstrItineraryData &InstrItins) const;
+
+  /// Check whether the CPU string is valid.
+  bool isCPUStringValid(StringRef CPU) const {
+    auto Found = std::lower_bound(ProcDesc.begin(), ProcDesc.end(), CPU);
+    return Found != ProcDesc.end() && StringRef(Found->Key) == CPU;
+  }
+
+  /// Returns string representation of scheduler comment
+  virtual std::string getSchedInfoStr(const MachineInstr &MI) const {
+    return {};
+  }
+
+  virtual std::string getSchedInfoStr(MCInst const &MCI) const {
+    return {};
+  }
+};
+
+} // end namespace llvm
+
+#endif // LLVM_MC_MCSUBTARGETINFO_H