Modify df_iterator to support post-order actions

Summary: This makes a change to the state used to maintain visited information for depth first iterator. We know assume a method "completed(...)" which is called after all children of a node have been visited. In all existing cases, this method does nothing so this patch has no functional changes.  It will however allow a client to distinguish back from cross edges in a DFS tree.

Reviewers: nadav, mehdi_amini, dberlin

Subscribers: MatzeB, mzolotukhin, twoh, freik, llvm-commits

Differential Revision: https://reviews.llvm.org/D25191

llvm-svn: 283391

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/MachineVerifier.cpp b/llvm/lib/CodeGen/MachineVerifier.cpp
index 33bf9abc8ef..6175313e391 100644
--- a/llvm/lib/CodeGen/MachineVerifier.cpp
+++ b/llvm/lib/CodeGen/MachineVerifier.cpp
@@ -2014,11 +2014,11 @@ void MachineVerifier::verifyStackFrame() {
 
   SmallVector<StackStateOfBB, 8> SPState;
   SPState.resize(MF->getNumBlockIDs());
-  SmallPtrSet<const MachineBasicBlock*, 8> Reachable;
+  df_iterator_default_set<const MachineBasicBlock*> Reachable;
 
   // Visit the MBBs in DFS order.
   for (df_ext_iterator<const MachineFunction*,
-                       SmallPtrSet<const MachineBasicBlock*, 8> >
+                       df_iterator_default_set<const MachineBasicBlock*> >
        DFI = df_ext_begin(MF, Reachable), DFE = df_ext_end(MF, Reachable);
        DFI != DFE; ++DFI) {
     const MachineBasicBlock *MBB = *DFI;