diff --git a/llvm/lib/CodeGen/ReachingDefAnalysis.cpp b/llvm/lib/CodeGen/ReachingDefAnalysis.cpp
--- a/llvm/lib/CodeGen/ReachingDefAnalysis.cpp
+++ b/llvm/lib/CodeGen/ReachingDefAnalysis.cpp
@@ -83,14 +83,16 @@
     if (Incoming.empty())
       continue;
 
-    for (unsigned Unit = 0; Unit != NumRegUnits; ++Unit) {
-      // Use the most recent predecessor def for each register.
+    // Find the most recent reaching definition from a predecessor.
+    for (unsigned Unit = 0; Unit != NumRegUnits; ++Unit)
       LiveRegs[Unit] = std::max(LiveRegs[Unit], Incoming[Unit]);
-      if ((LiveRegs[Unit] != ReachingDefDefaultVal))
-        MBBReachingDefs[MBBNumber][Unit].push_back(LiveRegs[Unit]);
-    }
   }
 
+  // Insert the most recent reaching definition we found.
+  for (unsigned Unit = 0; Unit != NumRegUnits; ++Unit)
+    if (LiveRegs[Unit] != ReachingDefDefaultVal)
+      MBBReachingDefs[MBBNumber][Unit].push_back(LiveRegs[Unit]);
+
   LLVM_DEBUG(dbgs() << printMBBReference(*MBB)
                     << (!TraversedMBB.IsDone ? ": incomplete\n"
                                              : ": all preds known\n"));