Subzero: Convert NULL->nullptr.

src/IceTargetLowering.cpp

 //===- subzero/src/IceTargetLowering.cpp - Basic lowering implementation --===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the skeleton of the TargetLowering class,
@@ skipping 80 matching lines @@
     return TargetX8632::create(Func);
 #if 0
   if (Target == Target_X8664)
     return IceTargetX8664::create(Func);
   if (Target == Target_ARM32)
     return IceTargetARM32::create(Func);
   if (Target == Target_ARM64)
     return IceTargetARM64::create(Func);
 #endif
   Func->setError("Unsupported target");
-  return NULL;
+  return nullptr;
 }
 
 TargetLowering::TargetLowering(Cfg *Func)
     : Func(Func), Ctx(Func->getContext()),
       RandomizeRegisterAllocation(CLRandomizeRegisterAllocation),
       HasComputedFrame(false), CallsReturnsTwice(false), StackAdjustment(0),
       Context() {}
 
 Assembler *TargetLowering::createAssembler(TargetArch Target, Cfg *Func) {
   // These statements can be #ifdef'd to specialize the assembler
   // to a subset of the available targets.  TODO: use CRTP.
   if (Target == Target_X8632)
     return new x86::AssemblerX86();
   Func->setError("Unsupported target");
-  return NULL;
+  return nullptr;
 }
 
 void TargetLowering::doAddressOpt() {
   if (llvm::isa<InstLoad>(*Context.getCur()))
     doAddressOptLoad();
   else if (llvm::isa<InstStore>(*Context.getCur()))
     doAddressOptStore();
   Context.advanceCur();
   Context.advanceNext();
 }
@@ skipping 133 matching lines @@
     return TargetGlobalInitX8632::create(Ctx);
 #if 0
   if (Target == Target_X8664)
     return IceTargetGlobalInitX8664::create(Ctx);
   if (Target == Target_ARM32)
     return IceTargetGlobalInitARM32::create(Ctx);
   if (Target == Target_ARM64)
     return IceTargetGlobalInitARM64::create(Ctx);
 #endif
   llvm_unreachable("Unsupported target");
-  return NULL;
+  return nullptr;
 }
 
 TargetGlobalInitLowering::~TargetGlobalInitLowering() {}
 
 } // end of namespace Ice