X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=blobdiff_plain;f=include%2Fllvm%2FADT%2Filist_node.h;h=03612440e7acdfb81101b0a1e85b737146c47d23;hp=9c7e6f6a51307248f5656c9c3102c069c63964b6;hb=674be02d525d4e24bc6943ed9274958c580bcfbc;hpb=5c3e7b171898612066afc86b8fa850cc32a0cd40

diff --git a/include/llvm/ADT/ilist_node.h b/include/llvm/ADT/ilist_node.h
index 9c7e6f6a513..03612440e7a 100644
--- a/include/llvm/ADT/ilist_node.h
+++ b/include/llvm/ADT/ilist_node.h
@@ -12,8 +12,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_ADT_ILIST_NODE_H
-#define LLVM_ADT_ILIST_NODE_H
+#ifndef LLVM_ADT_ILISTNODE_H
+#define LLVM_ADT_ILISTNODE_H
 
 namespace llvm {
 
@@ -40,7 +40,7 @@ struct ilist_nextprev_traits;
 /// that use ilist_nextprev_traits or ilist_default_traits.
 ///
 template<typename NodeTy>
-class ilist_node : ilist_half_node<NodeTy> {
+class ilist_node : private ilist_half_node<NodeTy> {
   friend struct ilist_nextprev_traits<NodeTy>;
   friend struct ilist_traits<NodeTy>;
   NodeTy *Next;
@@ -49,17 +49,57 @@ class ilist_node : ilist_half_node<NodeTy> {
   void setNext(NodeTy *N) { Next = N; }
 protected:
   ilist_node() : Next(0) {}
-};
 
-/// When assertions are off, the Next field of sentinels
-/// will not be accessed. So it is not necessary to allocate
-/// space for it. The following macro selects the most
-/// efficient trais class.
-#ifndef NDEBUG
-#   define ILIST_NODE ilist_node
-#else
-#   define ILIST_NODE ilist_half_node
-#endif
+public:
+  /// @name Adjacent Node Accessors
+  /// @{
+
+  /// \brief Get the previous node, or 0 for the list head.
+  NodeTy *getPrevNode() {
+    NodeTy *Prev = this->getPrev();
+
+    // Check for sentinel.
+    if (!Prev->getNext())
+      return 0;
+
+    return Prev;
+  }
+
+  /// \brief Get the previous node, or 0 for the list head.
+  const NodeTy *getPrevNode() const {
+    const NodeTy *Prev = this->getPrev();
+
+    // Check for sentinel.
+    if (!Prev->getNext())
+      return 0;
+
+    return Prev;
+  }
+
+  /// \brief Get the next node, or 0 for the list tail.
+  NodeTy *getNextNode() {
+    NodeTy *Next = getNext();
+
+    // Check for sentinel.
+    if (!Next->getNext())
+      return 0;
+
+    return Next;
+  }
+
+  /// \brief Get the next node, or 0 for the list tail.
+  const NodeTy *getNextNode() const {
+    const NodeTy *Next = getNext();
+
+    // Check for sentinel.
+    if (!Next->getNext())
+      return 0;
+
+    return Next;
+  }
+
+  /// @}
+};
 
 } // End llvm namespace