diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index 1709618..a512912 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -399,14 +399,13 @@
     // Iterate over all of the blocks that the variable is completely
     // live in, adding [insrtIndex(begin), instrIndex(end)+4) to the
     // live interval.
-    for (unsigned i = 0, e = vi.AliveBlocks.size(); i != e; ++i) {
-      if (vi.AliveBlocks[i]) {
-        LiveRange LR(getMBBStartIdx(i),
-                     getMBBEndIdx(i)+1,  // MBB ends at -1.
-                     ValNo);
-        interval.addRange(LR);
-        DOUT << " +" << LR;
-      }
+    for (int i = vi.AliveBlocks.find_first(); i != -1;
+         i = vi.AliveBlocks.find_next(i)) {
+      LiveRange LR(getMBBStartIdx(i),
+                   getMBBEndIdx(i)+1,  // MBB ends at -1.
+                   ValNo);
+      interval.addRange(LR);
+      DOUT << " +" << LR;
     }
 
     // Finally, this virtual register is live from the start of any killing
diff --git a/lib/CodeGen/LiveVariables.cpp b/lib/CodeGen/LiveVariables.cpp
index 632cd82..9fe42f6 100644
--- a/lib/CodeGen/LiveVariables.cpp
+++ b/lib/CodeGen/LiveVariables.cpp
@@ -52,11 +52,11 @@
 
 void LiveVariables::VarInfo::dump() const {
   cerr << "  Alive in blocks: ";
-  for (unsigned i = 0, e = AliveBlocks.size(); i != e; ++i)
-    if (AliveBlocks[i]) cerr << i << ", ";
+  for (int i = AliveBlocks.find_first(); i != -1; i = AliveBlocks.find_next(i))
+    cerr << i << ", ";
   cerr << "  Used in blocks: ";
-  for (unsigned i = 0, e = UsedBlocks.size(); i != e; ++i)
-    if (UsedBlocks[i]) cerr << i << ", ";
+  for (int i = UsedBlocks.find_first(); i != -1; i = UsedBlocks.find_next(i))
+    cerr << i << ", ";
   cerr << "\n  Killed by:";
   if (Kills.empty())
     cerr << " No instructions.\n";