X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FADT%2FPostOrderIterator.h;h=63a2b5219f738f446954ad936475363ec2afa32a;hb=5449a1db40b75586c1daf70a14396295e7b3fe24;hp=5760b2b552c214ac4b5d58aa04252c3268264f5b;hpb=f0891be8bdbeeadb39da5575273b6645755fa383;p=oota-llvm.git

diff --git a/include/llvm/ADT/PostOrderIterator.h b/include/llvm/ADT/PostOrderIterator.h
index 5760b2b552c..63a2b5219f7 100644
--- a/include/llvm/ADT/PostOrderIterator.h
+++ b/include/llvm/ADT/PostOrderIterator.h
@@ -19,7 +19,6 @@
 #include "llvm/ADT/GraphTraits.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include <set>
-#include <stack>
 #include <vector>
 
 namespace llvm {
@@ -30,6 +29,14 @@ public:
   SetType Visited;
 };
 
+/// DFSetTraits - Allow the SetType used to record depth-first search results to
+/// optionally record node postorder.
+template<class SetType>
+struct DFSetTraits {
+  static void finishPostorder(
+    typename SetType::iterator::value_type, SetType &) {}
+};
+
 template<class SetType>
 class po_iterator_storage<SetType, true> {
 public:
@@ -42,38 +49,38 @@ template<class GraphT,
   class SetType = llvm::SmallPtrSet<typename GraphTraits<GraphT>::NodeType*, 8>,
   bool ExtStorage = false,
   class GT = GraphTraits<GraphT> >
-class po_iterator : public std::iterator<std::forward_iterator_tag, typename GT::NodeType, ptrdiff_t>,
+class po_iterator : public std::iterator<std::forward_iterator_tag,
+                                         typename GT::NodeType, ptrdiff_t>,
                     public po_iterator_storage<SetType, ExtStorage> {
-  typedef std::iterator<std::forward_iterator_tag, typename GT::NodeType, ptrdiff_t> super;
+  typedef std::iterator<std::forward_iterator_tag,
+                        typename GT::NodeType, ptrdiff_t> super;
   typedef typename GT::NodeType          NodeType;
   typedef typename GT::ChildIteratorType ChildItTy;
 
   // VisitStack - Used to maintain the ordering.  Top = current block
   // First element is basic block pointer, second is the 'next child' to visit
-  std::stack<std::pair<NodeType *, ChildItTy> > VisitStack;
+  std::vector<std::pair<NodeType *, ChildItTy> > VisitStack;
 
   void traverseChild() {
-    while (VisitStack.top().second != GT::child_end(VisitStack.top().first)) {
-      NodeType *BB = *VisitStack.top().second++;
-      if (!this->Visited.count(BB)) {  // If the block is not visited...
-        this->Visited.insert(BB);
-        VisitStack.push(std::make_pair(BB, GT::child_begin(BB)));
+    while (VisitStack.back().second != GT::child_end(VisitStack.back().first)) {
+      NodeType *BB = *VisitStack.back().second++;
+      if (this->Visited.insert(BB)) {  // If the block is not visited...
+        VisitStack.push_back(std::make_pair(BB, GT::child_begin(BB)));
       }
     }
   }
 
   inline po_iterator(NodeType *BB) {
     this->Visited.insert(BB);
-    VisitStack.push(std::make_pair(BB, GT::child_begin(BB)));
+    VisitStack.push_back(std::make_pair(BB, GT::child_begin(BB)));
     traverseChild();
   }
   inline po_iterator() {} // End is when stack is empty.
 
   inline po_iterator(NodeType *BB, SetType &S) :
     po_iterator_storage<SetType, ExtStorage>(S) {
-    if(!S.count(BB)) {
-      this->Visited.insert(BB);
-      VisitStack.push(std::make_pair(BB, GT::child_begin(BB)));
+    if (this->Visited.insert(BB)) {
+      VisitStack.push_back(std::make_pair(BB, GT::child_begin(BB)));
       traverseChild();
     }
   }
@@ -100,7 +107,7 @@ public:
   inline bool operator!=(const _Self& x) const { return !operator==(x); }
 
   inline pointer operator*() const {
-    return VisitStack.top().first;
+    return VisitStack.back().first;
   }
 
   // This is a nonstandard operator-> that dereferences the pointer an extra
@@ -110,7 +117,9 @@ public:
   inline NodeType *operator->() const { return operator*(); }
 
   inline _Self& operator++() {   // Preincrement
-    VisitStack.pop();
+    DFSetTraits<SetType>::finishPostorder(VisitStack.back().first,
+                                          this->Visited);
+    VisitStack.pop_back();
     if (!VisitStack.empty())
       traverseChild();
     return *this;