Fix for PR3946, in which SmallVector could behave strangely in corner cases.

[oota-llvm.git] / include / llvm / ADT / DenseSet.h

diff --git a/include/llvm/ADT/DenseSet.h b/include/llvm/ADT/DenseSet.h
index b19dc5e2fc34224bf2a09a4d9a56db63bdc20d91..ce7344bc1f99b3eab218817559d9f3300cf8a182 100644 (file)
--- a/include/llvm/ADT/DenseSet.h
+++ b/include/llvm/ADT/DenseSet.h
@@ -2,8 +2,8 @@
 //
 //                     The LLVM Compiler Infrastructure
 //
-// This file was developed by Chris Lattner and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
@@ -24,36 +24,79 @@ namespace llvm {
 /// should be optimized later if there is a need.
 template<typename ValueT, typename ValueInfoT = DenseMapInfo<ValueT> >
 class DenseSet {
-  DenseMap<ValueT, char, ValueInfoT> TheMap;
+  typedef DenseMap<ValueT, char, ValueInfoT> MapTy;
+  MapTy TheMap;
 public:
   DenseSet(const DenseSet &Other) : TheMap(Other.TheMap) {}
   explicit DenseSet(unsigned NumInitBuckets = 64) : TheMap(NumInitBuckets) {}
-  
+
   bool empty() const { return TheMap.empty(); }
   unsigned size() const { return TheMap.size(); }
-  
-  // TODO add iterators.
-  
+
   void clear() {
     TheMap.clear();
   }
-  
+
   bool count(const ValueT &V) const {
     return TheMap.count(V);
   }
-  
-  void insert(const ValueT &V) {
-    TheMap[V] = 0;
-  }
-  
+
   void erase(const ValueT &V) {
     TheMap.erase(V);
   }
-  
+
   DenseSet &operator=(const DenseSet &RHS) {
     TheMap = RHS.TheMap;
     return *this;
   }
+
+  // Iterators.
+
+  class Iterator {
+    typename MapTy::iterator I;
+  public:
+    Iterator(const typename MapTy::iterator &i) : I(i) {}
+
+    ValueT& operator*() { return I->first; }
+    ValueT* operator->() { return &I->first; }
+
+    Iterator& operator++() { ++I; return *this; };
+    bool operator==(const Iterator& X) const { return I == X.I; }
+    bool operator!=(const Iterator& X) const { return I != X.I; }
+  };
+
+  class ConstIterator {
+    typename MapTy::const_iterator I;
+  public:
+    ConstIterator(const typename MapTy::const_iterator &i) : I(i) {}
+
+    const ValueT& operator*() { return I->first; }
+    const ValueT* operator->() { return &I->first; }
+
+    ConstIterator& operator++() { ++I; return *this; };
+    bool operator==(const ConstIterator& X) const { return I == X.I; }
+    bool operator!=(const ConstIterator& X) const { return I != X.I; }
+  };
+
+  typedef Iterator      iterator;
+  typedef ConstIterator const_iterator;
+
+  iterator begin() { return Iterator(TheMap.begin()); }
+  iterator end() { return Iterator(TheMap.end()); }
+
+  const_iterator begin() const { return ConstIterator(TheMap.begin()); }
+  const_iterator end() const { return ConstIterator(TheMap.end()); }
+
+  std::pair<iterator, bool> insert(const ValueT &V) {
+    return TheMap.insert(std::make_pair(V, 0));
+  }
+  
+  // Range insertion of values.
+  template<typename InputIt>
+  void insert(InputIt I, InputIt E) {
+    for (; I != E; ++I)
+      insert(*I);
+  }
 };
 
 } // end namespace llvm