precalculate number of words covered

moses/Bitmap.cpp

@@ -27,11 +27,47 @@ namespace Moses
 
 TO_STRING_BODY(Bitmap);
 
+Bitmap::Bitmap(size_t size, const std::vector<bool>& initializer)
+  :m_bitmap(initializer.begin(), initializer.end())
+{
+
+  // The initializer may not be of the same length.  Change to the desired
+  // length.  If we need to add any elements, initialize them to false.
+  m_bitmap.resize(size, false);
+
+  m_numWordsCovered = std::count(m_bitmap.begin(), m_bitmap.end(), true);
+
+  // Find the first gap, and cache it.
+  std::vector<char>::const_iterator first_gap = std::find(
+        m_bitmap.begin(), m_bitmap.end(), false);
+  m_firstGap = (
+                 (first_gap == m_bitmap.end()) ?
+                 NOT_FOUND : first_gap - m_bitmap.begin());
+}
+
+//! Create Bitmap of length size and initialise.
+Bitmap::Bitmap(size_t size)
+  :m_bitmap(size, false)
+   ,m_firstGap(0)
+   ,m_numWordsCovered(0)
+
+{
+}
+
+//! Deep copy.
+Bitmap::Bitmap(const Bitmap &copy)
+  :m_bitmap(copy.m_bitmap)
+  ,m_firstGap(copy.m_firstGap)
+  ,m_numWordsCovered(copy.m_numWordsCovered)
+{
+}
+
 Bitmap::Bitmap(const Bitmap &copy, const Range &range)
 :m_bitmap(copy.m_bitmap)
 ,m_firstGap(copy.m_firstGap)
+,m_numWordsCovered(copy.m_numWordsCovered)
 {
-	SetValue(range, true);
+	SetValueNonOverlap(range);
 }
 
 // for unordered_set in stack

moses/Bitmap.h

@@ -53,6 +53,7 @@ class Bitmap
 private:
   std::vector<char> m_bitmap; //! Ticks of words in sentence that have been done.
   size_t m_firstGap; //! Cached position of first gap, or NOT_FOUND.
+  size_t m_numWordsCovered;
 
   Bitmap(); // not implemented
   Bitmap& operator= (const Bitmap& other);
@@ -81,48 +82,33 @@ private:
 
   //! set value between 2 positions, inclusive
   void
-  SetValue(Range const& range, bool value) {
+  SetValueNonOverlap(Range const& range) {
 	  size_t startPos = range.GetStartPos();
 	  size_t endPos = range.GetEndPos();
 
 	  for(size_t pos = startPos ; pos <= endPos ; pos++) {
-	      m_bitmap[pos] = value;
+	      m_bitmap[pos] = true;
 	  }
-	  UpdateFirstGap(startPos, endPos, value);
+
+	  m_numWordsCovered += range.GetNumWordsCovered();
+	  UpdateFirstGap(startPos, endPos, true);
   }
 
 public:
   //! Create Bitmap of length size, and initialise with vector.
-  Bitmap(size_t size, const std::vector<bool>& initializer)
-    :m_bitmap(initializer.begin(), initializer.end()), m_firstGap(0) {
-
-    // The initializer may not be of the same length.  Change to the desired
-    // length.  If we need to add any elements, initialize them to false.
-    m_bitmap.resize(size, false);
-
-    // Find the first gap, and cache it.
-    std::vector<char>::const_iterator first_gap = std::find(
-          m_bitmap.begin(), m_bitmap.end(), false);
-    m_firstGap = (
-                   (first_gap == m_bitmap.end()) ?
-                   NOT_FOUND : first_gap - m_bitmap.begin());
-  }
+  Bitmap(size_t size, const std::vector<bool>& initializer);
 
   //! Create Bitmap of length size and initialise.
-  Bitmap(size_t size)
-    :m_bitmap(size, false), m_firstGap(0) {
-  }
+  Bitmap(size_t size);
 
   //! Deep copy.
-  Bitmap(const Bitmap &copy)
-    :m_bitmap(copy.m_bitmap), m_firstGap(copy.m_firstGap) {
-  }
+  Bitmap(const Bitmap &copy);
 
   Bitmap(const Bitmap &copy, const Range &range);
 
   //! Count of words translated.
   size_t GetNumWordsCovered() const {
-    return std::count(m_bitmap.begin(), m_bitmap.end(), true);
+    return m_numWordsCovered;
   }
 
   //! position of 1st word not yet translated, or NOT_FOUND if everything already translated
@@ -160,8 +146,20 @@ public:
   }
   //! set value at a particular position
   void SetValue( size_t pos, bool value ) {
-    m_bitmap[pos] = value;
-    UpdateFirstGap(pos, pos, value);
+    bool origValue = m_bitmap[pos];
+    if (origValue == value) {
+    	// do nothing
+    }
+    else {
+		m_bitmap[pos] = value;
+		UpdateFirstGap(pos, pos, value);
+		if (value) {
+			++m_numWordsCovered;
+		}
+		else {
+			--m_numWordsCovered;
+		}
+    }
   }
 
   //! whether every word has been translated