8366037: Remove oopDesc::mark_addr()

src/hotspot/share/gc/g1/g1OopClosures.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2025, 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
@@ -50,8 +50,8 @@ inline void G1ScanClosureBase::prefetch_and_push(T* p, const oop obj) {
   // stall. We'll try to prefetch the object (for write, given that
   // we might need to install the forwarding reference) and we'll
   // get back to it when pop it from the queue
-  Prefetch::write(obj->mark_addr(), 0);
-  Prefetch::read(obj->mark_addr(), (HeapWordSize*2));
+  Prefetch::write(obj->base_addr(), oopDesc::mark_offset_in_bytes());
+  Prefetch::read(obj->base_addr(), oopDesc::mark_offset_in_bytes() + (HeapWordSize*2));
 
   // slightly paranoid test; I'm trying to catch potential
   // problems before we go into push_on_queue to know where the

src/hotspot/share/gc/parallel/psPromotionManager.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2002, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2025, 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
@@ -61,7 +61,7 @@ inline void PSPromotionManager::claim_or_forward_depth(T* p) {
   if (PSScavenge::is_obj_in_young(heap_oop)) {
     oop obj = CompressedOops::decode_not_null(heap_oop);
     assert(!PSScavenge::is_obj_in_to_space(obj), "revisiting object?");
-    Prefetch::write(obj->mark_addr(), 0);
+    Prefetch::write(obj->base_addr(), oopDesc::mark_offset_in_bytes());
     push_depth(ScannerTask(p));
   }
 }

src/hotspot/share/oops/oop.hpp

@@ -65,9 +65,11 @@ class oopDesc {
   // Must be trivial; see verifying static assert after the class.
   oopDesc() = default;
 
+  inline void* base_addr();
+  inline const void* base_addr() const;
+
   inline markWord  mark()          const;
   inline markWord  mark_acquire()  const;
-  inline markWord* mark_addr() const;
 
   inline void set_mark(markWord m);
   static inline void set_mark(HeapWord* mem, markWord m);

src/hotspot/share/oops/oop.inline.hpp

@@ -47,6 +47,9 @@
 // Implementation of all inlined member functions defined in oop.hpp
 // We need a separate file to avoid circular references
 
+void* oopDesc::base_addr() { return this; }
+const void* oopDesc::base_addr() const { return this; }
+
 markWord oopDesc::mark() const {
   return Atomic::load(&_mark);
 }
@@ -55,10 +58,6 @@ markWord oopDesc::mark_acquire() const {
   return Atomic::load_acquire(&_mark);
 }
 
-markWord* oopDesc::mark_addr() const {
-  return (markWord*) &_mark;
-}
-
 void oopDesc::set_mark(markWord m) {
   Atomic::store(&_mark, m);
 }