8301493: Replace NULL with nullptr in cpu/aarch64

Reviewed-by: tschatzl, gziemski, dholmes

Author: jdksjolen

src/hotspot/cpu/aarch64/assembler_aarch64.cpp

@@ -102,7 +102,7 @@ void Assembler::emit_data64(jlong data,
                             RelocationHolder const& rspec,
                             int format) {
 
-  assert(inst_mark() != NULL, "must be inside InstructionMark");
+  assert(inst_mark() != nullptr, "must be inside InstructionMark");
   // Do not use AbstractAssembler::relocate, which is not intended for
   // embedded words.  Instead, relocate to the enclosing instruction.
   code_section()->relocate(inst_mark(), rspec, format);

src/hotspot/cpu/aarch64/c1_CodeStubs_aarch64.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2023, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2014, Red Hat Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -44,7 +44,7 @@ void C1SafepointPollStub::emit_code(LIR_Assembler* ce) {
   __ adr(rscratch1, safepoint_pc);
   __ str(rscratch1, Address(rthread, JavaThread::saved_exception_pc_offset()));
 
-  assert(SharedRuntime::polling_page_return_handler_blob() != NULL,
+  assert(SharedRuntime::polling_page_return_handler_blob() != nullptr,
          "polling page return stub not created yet");
   address stub = SharedRuntime::polling_page_return_handler_blob()->entry_point();
 
@@ -334,7 +334,7 @@ void ArrayCopyStub::emit_code(LIR_Assembler* ce) {
   Address resolve(SharedRuntime::get_resolve_static_call_stub(),
                   relocInfo::static_call_type);
   address call = __ trampoline_call(resolve);
-  if (call == NULL) {
+  if (call == nullptr) {
     ce->bailout("trampoline stub overflow");
     return;
   }