replace NULL with nullptr

lib/AST/Availability.cpp

@@ -127,7 +127,7 @@ AvailabilityInference::annotatedAvailableRange(const Decl *D, ASTContext &Ctx) {
 
   for (auto Attr : D->getAttrs()) {
     auto *AvailAttr = dyn_cast<AvailableAttr>(Attr);
-    if (AvailAttr == NULL || !AvailAttr->Introduced.hasValue() ||
+    if (AvailAttr == nullptr || !AvailAttr->Introduced.hasValue() ||
         !AvailAttr->isActivePlatform(Ctx)) {
       continue;
     }

lib/IDE/Utils.cpp

@@ -119,7 +119,7 @@ ide::isSourceInputComplete(std::unique_ptr<llvm::MemoryBuffer> MemBuf) {
   const char *SourceStart = Buffer.data();
   const char *SourceEnd = Buffer.data() + Buffer.size();
   const char *LineStart = SourceStart;
-  const char *LineSourceStart = NULL;
+  const char *LineSourceStart = nullptr;
   uint32_t LineIndent = 0;
   struct IndentInfo {
     StringRef Prefix;
@@ -134,7 +134,7 @@ ide::isSourceInputComplete(std::unique_ptr<llvm::MemoryBuffer> MemBuf) {
     case '\r':
     case '\n':
       LineIndent = 0;
-      LineSourceStart = NULL;
+      LineSourceStart = nullptr;
       LineStart = p + 1;
       break;
 
@@ -146,7 +146,7 @@ ide::isSourceInputComplete(std::unique_ptr<llvm::MemoryBuffer> MemBuf) {
     case '(':
     case '[':
       ++LineIndent;
-      if (LineSourceStart == NULL)
+      if (LineSourceStart == nullptr)
         IndentInfos.push_back(IndentInfo(LineStart,
                                          p - LineStart,
                                          LineIndent));
@@ -166,7 +166,7 @@ ide::isSourceInputComplete(std::unique_ptr<llvm::MemoryBuffer> MemBuf) {
       break;
 
     default:
-      if (LineSourceStart == NULL && !isspace(*p))
+      if (LineSourceStart == nullptr && !isspace(*p))
         LineSourceStart = p;
       break;
     }

lib/IRGen/IRGenSIL.cpp

@@ -1233,7 +1233,7 @@ static void emitEntryPointArgumentsCOrObjC(IRGenSILFunction &IGF,
   // all the value parameters.
   if (hasPolymorphicParameters(funcTy)) {
     emitPolymorphicParameters(IGF, *IGF.CurSILFn, params,
-                              NULL,
+                              nullptr,
       [&](unsigned paramIndex) -> llvm::Value* {
         SILValue parameter = entry->getBBArgs()[paramIndex];
         return IGF.getLoweredSingletonExplosion(parameter);

stdlib/public/runtime/Reflection.mm

@@ -598,7 +598,7 @@ static void getEnumMirrorInfo(const OpaqueValue *value,
                                       const OpaqueValue *value,
                                       const Metadata *type) {
   if (!isEnumReflectable(type))
-    return NULL;
+    return nullptr;
 
   const auto Enum = static_cast<const EnumMetadata *>(type);
   const auto &Description = Enum->Description->Enum;

stdlib/public/stubs/Stubs.cpp

@@ -328,7 +328,7 @@ static const char *_swift_stdlib_strtoX_clocale_impl(
   *outResult = result;
   if (result == huge || result == -huge || result == 0.0 || result == -0.0) {
       if (errno == ERANGE)
-          EndPtr = NULL;
+          EndPtr = nullptr;
   }
   return EndPtr;
 }