X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FADT%2FArrayRef.h;h=1b64fee9a597ab8e283534fcca77c4826ef6a428;hb=9becc6c2afc7d62fd855912eacd11586feb4a760;hp=bf9ff65ea20f69c0649cb98d294f1999104add90;hpb=fced2945995b4fd8f28f7dec9fcb5a6ab2e2798d;p=oota-llvm.git

diff --git a/include/llvm/ADT/ArrayRef.h b/include/llvm/ADT/ArrayRef.h
index bf9ff65ea20..1b64fee9a59 100644
--- a/include/llvm/ADT/ArrayRef.h
+++ b/include/llvm/ADT/ArrayRef.h
@@ -10,6 +10,7 @@
 #ifndef LLVM_ADT_ARRAYREF_H
 #define LLVM_ADT_ARRAYREF_H
 
+#include "llvm/ADT/None.h"
 #include "llvm/ADT/SmallVector.h"
 #include <vector>
 
@@ -33,6 +34,8 @@ namespace llvm {
     typedef const T *const_iterator;
     typedef size_t size_type;
 
+    typedef std::reverse_iterator<iterator> reverse_iterator;
+
   private:
     /// The start of the array, in an external buffer.
     const T *Data;
@@ -45,7 +48,10 @@ namespace llvm {
     /// @{
 
     /// Construct an empty ArrayRef.
-    /*implicit*/ ArrayRef() : Data(0), Length(0) {}
+    /*implicit*/ ArrayRef() : Data(nullptr), Length(0) {}
+
+    /// Construct an empty ArrayRef from None.
+    /*implicit*/ ArrayRef(NoneType) : Data(nullptr), Length(0) {}
 
     /// Construct an ArrayRef from a single element.
     /*implicit*/ ArrayRef(const T &OneElt)
@@ -59,19 +65,31 @@ namespace llvm {
     ArrayRef(const T *begin, const T *end)
       : Data(begin), Length(end - begin) {}
 
-    /// Construct an ArrayRef from a SmallVector.
-    /*implicit*/ ArrayRef(const SmallVectorImpl<T> &Vec)
-      : Data(Vec.data()), Length(Vec.size()) {}
+    /// Construct an ArrayRef from a SmallVector. This is templated in order to
+    /// avoid instantiating SmallVectorTemplateCommon<T> whenever we
+    /// copy-construct an ArrayRef.
+    template<typename U>
+    /*implicit*/ ArrayRef(const SmallVectorTemplateCommon<T, U> &Vec)
+      : Data(Vec.data()), Length(Vec.size()) {
+    }
 
     /// Construct an ArrayRef from a std::vector.
-    /*implicit*/ ArrayRef(const std::vector<T> &Vec)
-      : Data(Vec.empty() ? (T*)0 : &Vec[0]), Length(Vec.size()) {}
+    template<typename A>
+    /*implicit*/ ArrayRef(const std::vector<T, A> &Vec)
+      : Data(Vec.data()), Length(Vec.size()) {}
 
     /// Construct an ArrayRef from a C array.
     template <size_t N>
-    /*implicit*/ ArrayRef(const T (&Arr)[N])
+    /*implicit*/ LLVM_CONSTEXPR ArrayRef(const T (&Arr)[N])
       : Data(Arr), Length(N) {}
 
+#if LLVM_HAS_INITIALIZER_LISTS
+    /// Construct an ArrayRef from a std::initializer_list.
+    /*implicit*/ ArrayRef(const std::initializer_list<T> &Vec)
+    : Data(Vec.begin() == Vec.end() ? (T*)0 : Vec.begin()),
+      Length(Vec.size()) {}
+#endif
+
     /// @}
     /// @name Simple Operations
     /// @{
@@ -79,6 +97,9 @@ namespace llvm {
     iterator begin() const { return Data; }
     iterator end() const { return Data + Length; }
 
+    reverse_iterator rbegin() const { return reverse_iterator(end()); }
+    reverse_iterator rend() const { return reverse_iterator(begin()); }
+
     /// empty - Check if the array is empty.
     bool empty() const { return Length == 0; }
 
@@ -99,14 +120,18 @@ namespace llvm {
       return Data[Length-1];
     }
 
+    // copy - Allocate copy in Allocator and return ArrayRef<T> to it.
+    template <typename Allocator> ArrayRef<T> copy(Allocator &A) {
+      T *Buff = A.template Allocate<T>(Length);
+      std::copy(begin(), end(), Buff);
+      return ArrayRef<T>(Buff, Length);
+    }
+
     /// equals - Check for element-wise equality.
     bool equals(ArrayRef RHS) const {
       if (Length != RHS.Length)
         return false;
-      for (size_type i = 0; i != Length; i++)
-        if (Data[i] != RHS.Data[i])
-          return false;
-      return true;
+      return std::equal(begin(), end(), RHS.begin());
     }
 
     /// slice(n) - Chop off the first N elements of the array.
@@ -147,6 +172,96 @@ namespace llvm {
     /// @}
   };
 
+  /// MutableArrayRef - Represent a mutable reference to an array (0 or more
+  /// elements consecutively in memory), i.e. a start pointer and a length.  It
+  /// allows various APIs to take and modify consecutive elements easily and
+  /// conveniently.
+  ///
+  /// This class does not own the underlying data, it is expected to be used in
+  /// situations where the data resides in some other buffer, whose lifetime
+  /// extends past that of the MutableArrayRef. For this reason, it is not in
+  /// general safe to store a MutableArrayRef.
+  ///
+  /// This is intended to be trivially copyable, so it should be passed by
+  /// value.
+  template<typename T>
+  class MutableArrayRef : public ArrayRef<T> {
+  public:
+    typedef T *iterator;
+
+    typedef std::reverse_iterator<iterator> reverse_iterator;
+
+    /// Construct an empty MutableArrayRef.
+    /*implicit*/ MutableArrayRef() : ArrayRef<T>() {}
+
+    /// Construct an empty MutableArrayRef from None.
+    /*implicit*/ MutableArrayRef(NoneType) : ArrayRef<T>() {}
+
+    /// Construct an MutableArrayRef from a single element.
+    /*implicit*/ MutableArrayRef(T &OneElt) : ArrayRef<T>(OneElt) {}
+
+    /// Construct an MutableArrayRef from a pointer and length.
+    /*implicit*/ MutableArrayRef(T *data, size_t length)
+      : ArrayRef<T>(data, length) {}
+
+    /// Construct an MutableArrayRef from a range.
+    MutableArrayRef(T *begin, T *end) : ArrayRef<T>(begin, end) {}
+
+    /// Construct an MutableArrayRef from a SmallVector.
+    /*implicit*/ MutableArrayRef(SmallVectorImpl<T> &Vec)
+    : ArrayRef<T>(Vec) {}
+
+    /// Construct a MutableArrayRef from a std::vector.
+    /*implicit*/ MutableArrayRef(std::vector<T> &Vec)
+    : ArrayRef<T>(Vec) {}
+
+    /// Construct an MutableArrayRef from a C array.
+    template <size_t N>
+    /*implicit*/ LLVM_CONSTEXPR MutableArrayRef(T (&Arr)[N])
+      : ArrayRef<T>(Arr) {}
+
+    T *data() const { return const_cast<T*>(ArrayRef<T>::data()); }
+
+    iterator begin() const { return data(); }
+    iterator end() const { return data() + this->size(); }
+
+    reverse_iterator rbegin() const { return reverse_iterator(end()); }
+    reverse_iterator rend() const { return reverse_iterator(begin()); }
+
+    /// front - Get the first element.
+    T &front() const {
+      assert(!this->empty());
+      return data()[0];
+    }
+
+    /// back - Get the last element.
+    T &back() const {
+      assert(!this->empty());
+      return data()[this->size()-1];
+    }
+
+    /// slice(n) - Chop off the first N elements of the array.
+    MutableArrayRef<T> slice(unsigned N) const {
+      assert(N <= this->size() && "Invalid specifier");
+      return MutableArrayRef<T>(data()+N, this->size()-N);
+    }
+
+    /// slice(n, m) - Chop off the first N elements of the array, and keep M
+    /// elements in the array.
+    MutableArrayRef<T> slice(unsigned N, unsigned M) const {
+      assert(N+M <= this->size() && "Invalid specifier");
+      return MutableArrayRef<T>(data()+N, M);
+    }
+
+    /// @}
+    /// @name Operator Overloads
+    /// @{
+    T &operator[](size_t Index) const {
+      assert(Index < this->size() && "Invalid index!");
+      return data()[Index];
+    }
+  };
+
   /// @name ArrayRef Convenience constructors
   /// @{