1 files changed, 4 insertions, 3 deletions
diff --git a/lib/Transforms/Utils/SimplifyInstructions.cpp b/lib/Transforms/Utils/SimplifyInstructions.cpp
index bbd65f1752..6762527cf7 100644
--- a/lib/Transforms/Utils/SimplifyInstructions.cpp
+++ b/lib/Transforms/Utils/SimplifyInstructions.cpp
@@ -55,9 +55,10 @@ namespace {
       bool Changed = false;
 
       do {
-        for (df_iterator<BasicBlock*> DI = df_begin(&F.getEntryBlock()),
-             DE = df_end(&F.getEntryBlock()); DI != DE; ++DI)
-          for (BasicBlock::iterator BI = DI->begin(), BE = DI->end(); BI != BE;) {
+        for (BasicBlock *BB : depth_first(&F.getEntryBlock()))
+          // Here be subtlety: the iterator must be incremented before the loop
+          // body (not sure why), so a range-for loop won't work here.
+          for (BasicBlock::iterator BI = BB->begin(), BE = BB->end(); BI != BE;) {
             Instruction *I = BI++;
             // The first time through the loop ToSimplify is empty and we try to
             // simplify all instructions.  On later iterations ToSimplify is not