From 3059c3b69ec8fb7cefd740bc2eb52b5ca5390ae1 Mon Sep 17 00:00:00 2001
From: Kim Barrett <kbarrett@openjdk.org>
Date: Thu, 25 Jan 2024 05:44:18 +0000
Subject: [PATCH] 8324242: Avoid null check for OopHandle::ptr_raw()

Reviewed-by: shade, jsjolen, coleenp
---
 src/hotspot/share/classfile/classLoaderData.cpp | 8 ++++----
 src/hotspot/share/oops/klass.hpp                | 4 ++--
 src/hotspot/share/oops/oopHandle.inline.hpp     | 7 +++----
 src/hotspot/share/runtime/javaThread.cpp        | 4 ++--
 4 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/src/hotspot/share/classfile/classLoaderData.cpp b/src/hotspot/share/classfile/classLoaderData.cpp
index be91f26bdef..00687d21a7e 100644
--- a/src/hotspot/share/classfile/classLoaderData.cpp
+++ b/src/hotspot/share/classfile/classLoaderData.cpp
@@ -838,10 +838,10 @@ OopHandle ClassLoaderData::add_handle(Handle h) {
 
 void ClassLoaderData::remove_handle(OopHandle h) {
   assert(!is_unloading(), "Do not remove a handle for a CLD that is unloading");
-  oop* ptr = h.ptr_raw();
-  if (ptr != nullptr) {
-    assert(_handles.owner_of(ptr), "Got unexpected handle " PTR_FORMAT, p2i(ptr));
-    NativeAccess<>::oop_store(ptr, oop(nullptr));
+  if (!h.is_empty()) {
+    assert(_handles.owner_of(h.ptr_raw()),
+           "Got unexpected handle " PTR_FORMAT, p2i(h.ptr_raw()));
+    h.replace(oop(nullptr));
   }
 }
 
diff --git a/src/hotspot/share/oops/klass.hpp b/src/hotspot/share/oops/klass.hpp
index 96f8f8efdb6..0c9c05bed32 100644
--- a/src/hotspot/share/oops/klass.hpp
+++ b/src/hotspot/share/oops/klass.hpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -582,7 +582,7 @@ protected:
     if (has_archived_mirror_index()) {
       // _java_mirror is not a valid OopHandle but rather an encoded reference in the shared heap
       return false;
-    } else if (_java_mirror.ptr_raw() == nullptr) {
+    } else if (_java_mirror.is_empty()) {
       return false;
     } else {
       return true;
diff --git a/src/hotspot/share/oops/oopHandle.inline.hpp b/src/hotspot/share/oops/oopHandle.inline.hpp
index 95db9210e96..23a13cb35e3 100644
--- a/src/hotspot/share/oops/oopHandle.inline.hpp
+++ b/src/hotspot/share/oops/oopHandle.inline.hpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -57,9 +57,8 @@ inline void OopHandle::release(OopStorage* storage) {
 }
 
 inline void OopHandle::replace(oop obj) {
-  oop* ptr = ptr_raw();
-  assert(ptr != nullptr, "should not use replace");
-  NativeAccess<>::oop_store(ptr, obj);
+  assert(!is_empty(), "should not use replace");
+  NativeAccess<>::oop_store(_obj, obj);
 }
 
 inline oop OopHandle::xchg(oop new_value) {
diff --git a/src/hotspot/share/runtime/javaThread.cpp b/src/hotspot/share/runtime/javaThread.cpp
index a789988e379..9242fd65483 100644
--- a/src/hotspot/share/runtime/javaThread.cpp
+++ b/src/hotspot/share/runtime/javaThread.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2021, Azul Systems, Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -194,7 +194,7 @@ oop JavaThread::scopedValueCache() const {
 }
 
 void JavaThread::set_scopedValueCache(oop p) {
-  if (_scopedValueCache.ptr_raw() != nullptr) { // i.e. if the OopHandle has been allocated
+  if (!_scopedValueCache.is_empty()) { // i.e. if the OopHandle has been allocated
     _scopedValueCache.replace(p);
   } else {
     assert(p == nullptr, "not yet initialized");