diff --git a/compiler/optimizing/ssa_liveness_analysis.cc b/compiler/optimizing/ssa_liveness_analysis.cc
index c0d6f42..56ccd71 100644
--- a/compiler/optimizing/ssa_liveness_analysis.cc
+++ b/compiler/optimizing/ssa_liveness_analysis.cc
@@ -71,8 +71,8 @@
   //      for it.
   GrowableArray<uint32_t> forward_predecessors(graph_.GetArena(), graph_.GetBlocks().Size());
   forward_predecessors.SetSize(graph_.GetBlocks().Size());
-  for (size_t i = 0, e = graph_.GetBlocks().Size(); i < e; ++i) {
-    HBasicBlock* block = graph_.GetBlocks().Get(i);
+  for (HReversePostOrderIterator it(graph_); !it.Done(); it.Advance()) {
+    HBasicBlock* block = it.Current();
     size_t number_of_forward_predecessors = block->GetPredecessors().Size();
     if (block->IsLoopHeader()) {
       // We rely on having simplified the CFG.