Modernize raw_fd_ostream's constructor a bit.

[oota-llvm.git] / include / llvm / ADT / ilist_node.h

diff --git a/include/llvm/ADT/ilist_node.h b/include/llvm/ADT/ilist_node.h
index 9c7e6f6a51307248f5656c9c3102c069c63964b6..26d0b55e4093e3b34c6e1d63265f71eeb6382044 100644 (file)
--- a/include/llvm/ADT/ilist_node.h
+++ b/include/llvm/ADT/ilist_node.h
@@ -30,7 +30,7 @@ protected:
   NodeTy *getPrev() { return Prev; }
   const NodeTy *getPrev() const { return Prev; }
   void setPrev(NodeTy *P) { Prev = P; }
-  ilist_half_node() : Prev(0) {}
+  ilist_half_node() : Prev(nullptr) {}
 };
 
 template<typename NodeTy>
@@ -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;
@@ -48,18 +48,58 @@ class ilist_node : ilist_half_node<NodeTy> {
   const NodeTy *getNext() const { return Next; }
   void setNext(NodeTy *N) { Next = N; }
 protected:
-  ilist_node() : Next(0) {}
-};
+  ilist_node() : Next(nullptr) {}
 
-/// 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 nullptr;
+
+    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 nullptr;
+
+    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 nullptr;
+
+    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 nullptr;
+
+    return Next;
+  }
+
+  /// @}
+};
 
 } // End llvm namespace