[ADT] Fix a confusing interface spec and some annoying peculiarities

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

diff --git a/include/llvm/ADT/UniqueVector.h b/include/llvm/ADT/UniqueVector.h
index edb7d1a719ab5cf726d81a92f958f2c44aaafc64..a9cb2f5709eb2dc6cd5211aa1643ec7bc8aab8bd 100644 (file)
--- a/include/llvm/ADT/UniqueVector.h
+++ b/include/llvm/ADT/UniqueVector.h
@@ -1,16 +1,16 @@
-
 //===-- llvm/ADT/UniqueVector.h ---------------------------------*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
-// This file was developed by James M. Laskey 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.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_ADT_UNIQUEVECTOR_H
 #define LLVM_ADT_UNIQUEVECTOR_H
 
+#include <cassert>
 #include <map>
 #include <vector>
 
@@ -20,49 +20,85 @@ namespace llvm {
 /// UniqueVector - This class produces a sequential ID number (base 1) for each
 /// unique entry that is added.  T is the type of entries in the vector. This
 /// class should have an implementation of operator== and of operator<.
-/// Entries can be fetched using operator[] with the entry ID. 
+/// Entries can be fetched using operator[] with the entry ID.
 template<class T> class UniqueVector {
+public:
+  typedef typename std::vector<T> VectorType;
+  typedef typename VectorType::iterator iterator;
+  typedef typename VectorType::const_iterator const_iterator;
+
 private:
   // Map - Used to handle the correspondence of entry to ID.
   std::map<T, unsigned> Map;
 
   // Vector - ID ordered vector of entries. Entries can be indexed by ID - 1.
   //
-  std::vector<const T *> Vector;
-  
+  VectorType Vector;
+
 public:
   /// insert - Append entry to the vector if it doesn't already exist.  Returns
   /// the entry's index + 1 to be used as a unique ID.
   unsigned insert(const T &Entry) {
     // Check if the entry is already in the map.
-    typename std::map<T, unsigned>::iterator MI = Map.lower_bound(Entry);
-    
+    unsigned &Val = Map[Entry];
+
     // See if entry exists, if so return prior ID.
-    if (MI != Map.end() && MI->first == Entry) return MI->second;
+    if (Val) return Val;
 
     // Compute ID for entry.
-    unsigned ID = Vector.size() + 1;
-    
-    // Insert in map.
-    MI = Map.insert(MI, std::make_pair(Entry, ID));
-    
+    Val = static_cast<unsigned>(Vector.size()) + 1;
+
     // Insert in vector.
-    Vector.push_back(&MI->first);
+    Vector.push_back(Entry);
+    return Val;
+  }
+
+  /// idFor - return the ID for an existing entry.  Returns 0 if the entry is
+  /// not found.
+  unsigned idFor(const T &Entry) const {
+    // Search for entry in the map.
+    typename std::map<T, unsigned>::const_iterator MI = Map.find(Entry);
 
-    return ID;
+    // See if entry exists, if so return ID.
+    if (MI != Map.end()) return MI->second;
+
+    // No luck.
+    return 0;
   }
-  
+
   /// operator[] - Returns a reference to the entry with the specified ID.
   ///
-  const T &operator[](unsigned ID) const { return *Vector[ID - 1]; }
-  
+  const T &operator[](unsigned ID) const {
+    assert(ID-1 < size() && "ID is 0 or out of range!");
+    return Vector[ID - 1];
+  }
+
+  /// \brief Return an iterator to the start of the vector.
+  iterator begin() { return Vector.begin(); }
+
+  /// \brief Return an iterator to the start of the vector.
+  const_iterator begin() const { return Vector.begin(); }
+
+  /// \brief Return an iterator to the end of the vector.
+  iterator end() { return Vector.end(); }
+
+  /// \brief Return an iterator to the end of the vector.
+  const_iterator end() const { return Vector.end(); }
+
   /// size - Returns the number of entries in the vector.
   ///
   size_t size() const { return Vector.size(); }
-  
+
   /// empty - Returns true if the vector is empty.
   ///
   bool empty() const { return Vector.empty(); }
+
+  /// reset - Clears all the entries.
+  ///
+  void reset() {
+    Map.clear();
+    Vector.resize(0, 0);
+  }
 };
 
 } // End of namespace llvm