Import prebuilt clang toolchain for linux.
diff --git a/linux-x64/clang/include/llvm/ADT/DenseMapInfo.h b/linux-x64/clang/include/llvm/ADT/DenseMapInfo.h
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+++ b/linux-x64/clang/include/llvm/ADT/DenseMapInfo.h
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+//===- llvm/ADT/DenseMapInfo.h - Type traits for DenseMap -------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines DenseMapInfo traits for DenseMap.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ADT_DENSEMAPINFO_H
+#define LLVM_ADT_DENSEMAPINFO_H
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/Hashing.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/PointerLikeTypeTraits.h"
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+#include <utility>
+
+namespace llvm {
+
+template<typename T>
+struct DenseMapInfo {
+  //static inline T getEmptyKey();
+  //static inline T getTombstoneKey();
+  //static unsigned getHashValue(const T &Val);
+  //static bool isEqual(const T &LHS, const T &RHS);
+};
+
+// Provide DenseMapInfo for all pointers.
+template<typename T>
+struct DenseMapInfo<T*> {
+  static inline T* getEmptyKey() {
+    uintptr_t Val = static_cast<uintptr_t>(-1);
+    Val <<= PointerLikeTypeTraits<T*>::NumLowBitsAvailable;
+    return reinterpret_cast<T*>(Val);
+  }
+
+  static inline T* getTombstoneKey() {
+    uintptr_t Val = static_cast<uintptr_t>(-2);
+    Val <<= PointerLikeTypeTraits<T*>::NumLowBitsAvailable;
+    return reinterpret_cast<T*>(Val);
+  }
+
+  static unsigned getHashValue(const T *PtrVal) {
+    return (unsigned((uintptr_t)PtrVal) >> 4) ^
+           (unsigned((uintptr_t)PtrVal) >> 9);
+  }
+
+  static bool isEqual(const T *LHS, const T *RHS) { return LHS == RHS; }
+};
+
+// Provide DenseMapInfo for chars.
+template<> struct DenseMapInfo<char> {
+  static inline char getEmptyKey() { return ~0; }
+  static inline char getTombstoneKey() { return ~0 - 1; }
+  static unsigned getHashValue(const char& Val) { return Val * 37U; }
+
+  static bool isEqual(const char &LHS, const char &RHS) {
+    return LHS == RHS;
+  }
+};
+
+// Provide DenseMapInfo for unsigned shorts.
+template <> struct DenseMapInfo<unsigned short> {
+  static inline unsigned short getEmptyKey() { return 0xFFFF; }
+  static inline unsigned short getTombstoneKey() { return 0xFFFF - 1; }
+  static unsigned getHashValue(const unsigned short &Val) { return Val * 37U; }
+
+  static bool isEqual(const unsigned short &LHS, const unsigned short &RHS) {
+    return LHS == RHS;
+  }
+};
+
+// Provide DenseMapInfo for unsigned ints.
+template<> struct DenseMapInfo<unsigned> {
+  static inline unsigned getEmptyKey() { return ~0U; }
+  static inline unsigned getTombstoneKey() { return ~0U - 1; }
+  static unsigned getHashValue(const unsigned& Val) { return Val * 37U; }
+
+  static bool isEqual(const unsigned& LHS, const unsigned& RHS) {
+    return LHS == RHS;
+  }
+};
+
+// Provide DenseMapInfo for unsigned longs.
+template<> struct DenseMapInfo<unsigned long> {
+  static inline unsigned long getEmptyKey() { return ~0UL; }
+  static inline unsigned long getTombstoneKey() { return ~0UL - 1L; }
+
+  static unsigned getHashValue(const unsigned long& Val) {
+    return (unsigned)(Val * 37UL);
+  }
+
+  static bool isEqual(const unsigned long& LHS, const unsigned long& RHS) {
+    return LHS == RHS;
+  }
+};
+
+// Provide DenseMapInfo for unsigned long longs.
+template<> struct DenseMapInfo<unsigned long long> {
+  static inline unsigned long long getEmptyKey() { return ~0ULL; }
+  static inline unsigned long long getTombstoneKey() { return ~0ULL - 1ULL; }
+
+  static unsigned getHashValue(const unsigned long long& Val) {
+    return (unsigned)(Val * 37ULL);
+  }
+
+  static bool isEqual(const unsigned long long& LHS,
+                      const unsigned long long& RHS) {
+    return LHS == RHS;
+  }
+};
+
+// Provide DenseMapInfo for shorts.
+template <> struct DenseMapInfo<short> {
+  static inline short getEmptyKey() { return 0x7FFF; }
+  static inline short getTombstoneKey() { return -0x7FFF - 1; }
+  static unsigned getHashValue(const short &Val) { return Val * 37U; }
+  static bool isEqual(const short &LHS, const short &RHS) { return LHS == RHS; }
+};
+
+// Provide DenseMapInfo for ints.
+template<> struct DenseMapInfo<int> {
+  static inline int getEmptyKey() { return 0x7fffffff; }
+  static inline int getTombstoneKey() { return -0x7fffffff - 1; }
+  static unsigned getHashValue(const int& Val) { return (unsigned)(Val * 37U); }
+
+  static bool isEqual(const int& LHS, const int& RHS) {
+    return LHS == RHS;
+  }
+};
+
+// Provide DenseMapInfo for longs.
+template<> struct DenseMapInfo<long> {
+  static inline long getEmptyKey() {
+    return (1UL << (sizeof(long) * 8 - 1)) - 1UL;
+  }
+
+  static inline long getTombstoneKey() { return getEmptyKey() - 1L; }
+
+  static unsigned getHashValue(const long& Val) {
+    return (unsigned)(Val * 37UL);
+  }
+
+  static bool isEqual(const long& LHS, const long& RHS) {
+    return LHS == RHS;
+  }
+};
+
+// Provide DenseMapInfo for long longs.
+template<> struct DenseMapInfo<long long> {
+  static inline long long getEmptyKey() { return 0x7fffffffffffffffLL; }
+  static inline long long getTombstoneKey() { return -0x7fffffffffffffffLL-1; }
+
+  static unsigned getHashValue(const long long& Val) {
+    return (unsigned)(Val * 37ULL);
+  }
+
+  static bool isEqual(const long long& LHS,
+                      const long long& RHS) {
+    return LHS == RHS;
+  }
+};
+
+// Provide DenseMapInfo for all pairs whose members have info.
+template<typename T, typename U>
+struct DenseMapInfo<std::pair<T, U>> {
+  using Pair = std::pair<T, U>;
+  using FirstInfo = DenseMapInfo<T>;
+  using SecondInfo = DenseMapInfo<U>;
+
+  static inline Pair getEmptyKey() {
+    return std::make_pair(FirstInfo::getEmptyKey(),
+                          SecondInfo::getEmptyKey());
+  }
+
+  static inline Pair getTombstoneKey() {
+    return std::make_pair(FirstInfo::getTombstoneKey(),
+                          SecondInfo::getTombstoneKey());
+  }
+
+  static unsigned getHashValue(const Pair& PairVal) {
+    uint64_t key = (uint64_t)FirstInfo::getHashValue(PairVal.first) << 32
+          | (uint64_t)SecondInfo::getHashValue(PairVal.second);
+    key += ~(key << 32);
+    key ^= (key >> 22);
+    key += ~(key << 13);
+    key ^= (key >> 8);
+    key += (key << 3);
+    key ^= (key >> 15);
+    key += ~(key << 27);
+    key ^= (key >> 31);
+    return (unsigned)key;
+  }
+
+  static bool isEqual(const Pair &LHS, const Pair &RHS) {
+    return FirstInfo::isEqual(LHS.first, RHS.first) &&
+           SecondInfo::isEqual(LHS.second, RHS.second);
+  }
+};
+
+// Provide DenseMapInfo for StringRefs.
+template <> struct DenseMapInfo<StringRef> {
+  static inline StringRef getEmptyKey() {
+    return StringRef(reinterpret_cast<const char *>(~static_cast<uintptr_t>(0)),
+                     0);
+  }
+
+  static inline StringRef getTombstoneKey() {
+    return StringRef(reinterpret_cast<const char *>(~static_cast<uintptr_t>(1)),
+                     0);
+  }
+
+  static unsigned getHashValue(StringRef Val) {
+    assert(Val.data() != getEmptyKey().data() && "Cannot hash the empty key!");
+    assert(Val.data() != getTombstoneKey().data() &&
+           "Cannot hash the tombstone key!");
+    return (unsigned)(hash_value(Val));
+  }
+
+  static bool isEqual(StringRef LHS, StringRef RHS) {
+    if (RHS.data() == getEmptyKey().data())
+      return LHS.data() == getEmptyKey().data();
+    if (RHS.data() == getTombstoneKey().data())
+      return LHS.data() == getTombstoneKey().data();
+    return LHS == RHS;
+  }
+};
+
+// Provide DenseMapInfo for ArrayRefs.
+template <typename T> struct DenseMapInfo<ArrayRef<T>> {
+  static inline ArrayRef<T> getEmptyKey() {
+    return ArrayRef<T>(reinterpret_cast<const T *>(~static_cast<uintptr_t>(0)),
+                       size_t(0));
+  }
+
+  static inline ArrayRef<T> getTombstoneKey() {
+    return ArrayRef<T>(reinterpret_cast<const T *>(~static_cast<uintptr_t>(1)),
+                       size_t(0));
+  }
+
+  static unsigned getHashValue(ArrayRef<T> Val) {
+    assert(Val.data() != getEmptyKey().data() && "Cannot hash the empty key!");
+    assert(Val.data() != getTombstoneKey().data() &&
+           "Cannot hash the tombstone key!");
+    return (unsigned)(hash_value(Val));
+  }
+
+  static bool isEqual(ArrayRef<T> LHS, ArrayRef<T> RHS) {
+    if (RHS.data() == getEmptyKey().data())
+      return LHS.data() == getEmptyKey().data();
+    if (RHS.data() == getTombstoneKey().data())
+      return LHS.data() == getTombstoneKey().data();
+    return LHS == RHS;
+  }
+};
+
+} // end namespace llvm
+
+#endif // LLVM_ADT_DENSEMAPINFO_H