[NFC] [hwasan] use for_each and move comment

Author: fmayer

llvm/lib/Transforms/Utils/MemoryTaggingSupport.cpp

@@ -12,6 +12,7 @@
 
 #include "llvm/Transforms/Utils/MemoryTaggingSupport.h"
 
+#include "llvm/ADT/STLExtras.h"
 #include "llvm/Analysis/CFG.h"
 #include "llvm/Analysis/PostDominators.h"
 #include "llvm/Analysis/StackSafetyAnalysis.h"
@@ -69,14 +70,12 @@ bool forAllReachableExits(const DominatorTree &DT, const PostDominatorTree &PDT,
       ++NumCoveredExits;
     }
   }
-  // If there's a mix of covered and non-covered exits, just put the untag
-  // on exits, so we avoid the redundancy of untagging twice.
   if (NumCoveredExits == ReachableRetVec.size()) {
-    for (auto *End : Ends)
-      Callback(End);
+    for_each(Ends, Callback);
   } else {
-    for (auto *RI : ReachableRetVec)
-      Callback(RI);
+    // If there's a mix of covered and non-covered exits, just put the untag
+    // on exits, so we avoid the redundancy of untagging twice.
+    for_each(ReachableRetVec, Callback);
     // We may have inserted untag outside of the lifetime interval.
     // Signal the caller to remove the lifetime end call for this alloca.
     return false;