Changes for LLDB upstream merge

include/llvm/ADT/ArrayRef.h

@@ -195,6 +195,22 @@ namespace llvm {
       return slice(0, size() - N);
     }
 
+    /// \brief Return a copy of *this with only the first \p N elements.
+    LLVM_ATTRIBUTE_UNUSED_RESULT
+    ArrayRef<T> take_front(size_t N = 1) const {
+      if (N >= size())
+        return *this;
+      return drop_back(size() - N);
+    }
+
+    /// \brief Return a copy of *this with only the last \p N elements.
+    LLVM_ATTRIBUTE_UNUSED_RESULT
+    ArrayRef<T> take_back(size_t N = 1) const {
+      if (N >= size())
+        return *this;
+      return drop_front(size() - N);
+    }
+
     /// @}
     /// @name Operator Overloads
     /// @{
@@ -203,6 +219,22 @@ namespace llvm {
       return Data[Index];
     }
 
+    /// Disallow accidental assignment from a temporary.
+    ///
+    /// The declaration here is extra complicated so that "arrayRef = {}"
+    /// continues to select the move assignment operator.
+    template <typename U>
+    typename std::enable_if<std::is_same<U, T>::value, ArrayRef<T>>::type &
+    operator=(U &&Temporary) = delete;
+
+    /// Disallow accidental assignment from a temporary.
+    ///
+    /// The declaration here is extra complicated so that "arrayRef = {}"
+    /// continues to select the move assignment operator.
+    template <typename U>
+    typename std::enable_if<std::is_same<U, T>::value, ArrayRef<T>>::type &
+    operator=(std::initializer_list<U>) = delete;
+
     /// @}
     /// @name Expensive Operations
     /// @{
@@ -321,6 +353,22 @@ namespace llvm {
       return slice(0, this->size() - N);
     }
 
+    /// \brief Return a copy of *this with only the first \p N elements.
+    LLVM_ATTRIBUTE_UNUSED_RESULT
+    MutableArrayRef<T> take_front(size_t N = 1) const {
+      if (N >= this->size())
+        return *this;
+      return drop_back(this->size() - N);
+    }
+
+    /// \brief Return a copy of *this with only the last \p N elements.
+    LLVM_ATTRIBUTE_UNUSED_RESULT
+    MutableArrayRef<T> take_back(size_t N = 1) const {
+      if (N >= this->size())
+        return *this;
+      return drop_front(this->size() - N);
+    }
+
     /// @}
     /// @name Operator Overloads
     /// @{

include/llvm/ADT/STLExtras.h

@@ -35,7 +35,7 @@ namespace llvm {
 namespace detail {
 
 template <typename RangeT>
-using IterOfRange = decltype(std::begin(std::declval<RangeT>()));
+using IterOfRange = decltype(std::begin(std::declval<RangeT &>()));
 
 } // End detail namespace
 
@@ -369,6 +369,11 @@ struct build_index_impl<0, I...> : index_sequence<I...> {};
 template <class... Ts>
 struct index_sequence_for : build_index_impl<sizeof...(Ts)> {};
 
+/// Utility type to build an inheritance chain that makes it easy to rank
+/// overload candidates.
+template <int N> struct rank : rank<N - 1> {};
+template <> struct rank<0> {};
+
 //===----------------------------------------------------------------------===//
 //     Extra additions for arrays
 //===----------------------------------------------------------------------===//
@@ -608,6 +613,70 @@ template <typename T> struct deref {
   }
 };
 
+namespace detail {
+template <typename R> class enumerator_impl {
+public:
+  template <typename X> struct result_pair {
+    result_pair(std::size_t Index, X Value) : Index(Index), Value(Value) {}
+
+    const std::size_t Index;
+    X Value;
+  };
+
+  class iterator {
+    typedef
+        typename std::iterator_traits<IterOfRange<R>>::reference iter_reference;
+    typedef result_pair<iter_reference> result_type;
+
+  public:
+    iterator(IterOfRange<R> &&Iter, std::size_t Index)
+        : Iter(Iter), Index(Index) {}
+
+    result_type operator*() const { return result_type(Index, *Iter); }
+
+    iterator &operator++() {
+      ++Iter;
+      ++Index;
+      return *this;
+    }
+
+    bool operator!=(const iterator &RHS) const { return Iter != RHS.Iter; }
+
+  private:
+    IterOfRange<R> Iter;
+    std::size_t Index;
+  };
+
+public:
+  explicit enumerator_impl(R &&Range) : Range(std::forward<R>(Range)) {}
+
+  iterator begin() { return iterator(std::begin(Range), 0); }
+  iterator end() { return iterator(std::end(Range), std::size_t(-1)); }
+
+private:
+  R Range;
+};
+}
+
+/// Given an input range, returns a new range whose values are are pair (A,B)
+/// such that A is the 0-based index of the item in the sequence, and B is
+/// the value from the original sequence.  Example:
+///
+/// std::vector<char> Items = {'A', 'B', 'C', 'D'};
+/// for (auto X : enumerate(Items)) {
+///   printf("Item %d - %c\n", X.Item, X.Value);
+/// }
+///
+/// Output:
+///   Item 0 - A
+///   Item 1 - B
+///   Item 2 - C
+///   Item 3 - D
+///
+template <typename R> detail::enumerator_impl<R> enumerate(R &&Range) {
+  return detail::enumerator_impl<R>(std::forward<R>(Range));
+}
+
 } // End llvm namespace
 
 #endif

include/llvm/ADT/StringExtras.h

@@ -19,6 +19,7 @@
 #include <iterator>
 
 namespace llvm {
+class raw_ostream;
 template<typename T> class SmallVectorImpl;
 
 /// hexdigit - Return the hexadecimal character for the
@@ -150,6 +151,12 @@ static inline StringRef getOrdinalSuffix(unsigned Val) {
   }
 }
 
+/// PrintEscapedString - Print each character of the specified string, escaping
+/// it if it is not printable or if it is an escape char.
+void PrintEscapedString(StringRef Name, raw_ostream &Out);
+
+namespace detail {
+
 template <typename IteratorT>
 inline std::string join_impl(IteratorT Begin, IteratorT End,
                              StringRef Separator, std::input_iterator_tag) {
@@ -184,12 +191,64 @@ inline std::string join_impl(IteratorT Begin, IteratorT End,
   return S;
 }
 
+template <typename Sep>
+inline void join_items_impl(std::string &Result, Sep Separator) {}
+
+template <typename Sep, typename Arg>
+inline void join_items_impl(std::string &Result, Sep Separator,
+                            const Arg &Item) {
+  Result += Item;
+}
+
+template <typename Sep, typename Arg1, typename... Args>
+inline void join_items_impl(std::string &Result, Sep Separator, const Arg1 &A1,
+                            Args &&... Items) {
+  Result += A1;
+  Result += Separator;
+  join_items_impl(Result, Separator, std::forward<Args>(Items)...);
+}
+
+inline size_t join_one_item_size(char C) { return 1; }
+inline size_t join_one_item_size(const char *S) { return S ? ::strlen(S) : 0; }
+
+template <typename T> inline size_t join_one_item_size(const T &Str) {
+  return Str.size();
+}
+
+inline size_t join_items_size() { return 0; }
+
+template <typename A1> inline size_t join_items_size(const A1 &A) {
+  return join_one_item_size(A);
+}
+template <typename A1, typename... Args>
+inline size_t join_items_size(const A1 &A, Args &&... Items) {
+  return join_one_item_size(A) + join_items_size(std::forward<Args>(Items)...);
+}
+}
+
 /// Joins the strings in the range [Begin, End), adding Separator between
 /// the elements.
 template <typename IteratorT>
 inline std::string join(IteratorT Begin, IteratorT End, StringRef Separator) {
   typedef typename std::iterator_traits<IteratorT>::iterator_category tag;
-  return join_impl(Begin, End, Separator, tag());
+  return detail::join_impl(Begin, End, Separator, tag());
+}
+
+/// Joins the strings in the parameter pack \p Items, adding \p Separator
+/// between the elements.  All arguments must be implicitly convertible to
+/// std::string, or there should be an overload of std::string::operator+=()
+/// that accepts the argument explicitly.
+template <typename Sep, typename... Args>
+inline std::string join_items(Sep Separator, Args &&... Items) {
+  std::string Result;
+  if (sizeof...(Items) == 0)
+    return Result;
+
+  size_t NS = detail::join_one_item_size(Separator);
+  size_t NI = detail::join_items_size(std::forward<Args>(Items)...);
+  Result.reserve(NI + (sizeof...(Items) - 1) * NS + 1);
+  detail::join_items_impl(Result, Separator, std::forward<Args>(Items)...);
+  return Result;
 }
 
 } // End llvm namespace