Subzero: Convert NULL->nullptr.

src/IceCfg.h

 //===- subzero/src/IceCfg.h - Control flow graph ----------------*- C++ -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file declares the Cfg class, which represents the control flow
@@ skipping 136 matching lines @@
   void genFrame();
   void livenessLightweight();
   void liveness(LivenessMode Mode);
   bool validateLiveness() const;
   void contractEmptyNodes();
   void doBranchOpt();
 
   // Manage the CurrentNode field, which is used for validating the
   // Variable::DefNode field during dumping/emitting.
   void setCurrentNode(const CfgNode *Node) { CurrentNode = Node; }
-  void resetCurrentNode() { setCurrentNode(NULL); }
+  void resetCurrentNode() { setCurrentNode(nullptr); }
   const CfgNode *getCurrentNode() const { return CurrentNode; }
 
   void emit();
   void emitIAS();
   void emitTextHeader(const IceString &MangledName);
   void dump(const IceString &Message = "");
 
   // Allocate data of type T using the per-Cfg allocator.
   template <typename T> T *allocate() { return Allocator->Allocate<T>(); }
 
@@ skipping 44 matching lines @@
 
   // Maintain a pointer in TLS to the current Cfg being translated.
   // This is primarily for accessing its allocator statelessly, but
   // other uses are possible.
   thread_local static const Cfg *CurrentCfg;
 };
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICECFG_H