Handle has_klass_gap

rkennke · Nov 13, 2024 · 9e770b8 · 9e770b8
1 parent f179d17
commit 9e770b8
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Showing 3 changed files with 9 additions and 1 deletion.
diff --git a/src/hotspot/share/oops/objLayout.cpp b/src/hotspot/share/oops/objLayout.cpp
@@ -30,17 +30,21 @@
 
 ObjLayout::Mode ObjLayout::_klass_mode = ObjLayout::Undefined;
 int ObjLayout::_oop_base_offset_in_bytes = 0;
+bool ObjLayout::_oop_has_klass_gap = false;
 
 void ObjLayout::initialize() {
   assert(_klass_mode == Undefined, "ObjLayout initialized twice");
   if (UseCompactObjectHeaders) {
     _klass_mode = Compact;
     _oop_base_offset_in_bytes = sizeof(markWord);
+    _oop_has_klass_gap = false;
   } else if (UseCompressedClassPointers) {
     _klass_mode = Compressed;
     _oop_base_offset_in_bytes = sizeof(markWord) + sizeof(narrowKlass);
+    _oop_has_klass_gap = true;
   } else {
     _klass_mode = Uncompressed;
     _oop_base_offset_in_bytes = sizeof(markWord) + sizeof(Klass*);
+    _oop_has_klass_gap = false;
   }
 }
diff --git a/src/hotspot/share/oops/objLayout.hpp b/src/hotspot/share/oops/objLayout.hpp
@@ -66,13 +66,17 @@ class ObjLayout {
 private:
   static Mode _klass_mode;
   static int  _oop_base_offset_in_bytes;
+  static bool _oop_has_klass_gap;
 
 public:
   static void initialize();
   static inline Mode klass_mode();
   static inline int oop_base_offset_in_bytes() {
     return _oop_base_offset_in_bytes;
   }
+  static inline bool oop_has_klass_gap() {
+    return _oop_has_klass_gap;
+  }
 };
 
 #endif // SHARE_OOPS_OBJLAYOUT_HPP
diff --git a/src/hotspot/share/oops/oop.cpp b/src/hotspot/share/oops/oop.cpp
@@ -153,7 +153,7 @@ bool oopDesc::is_objArray_noinline()    const { return is_objArray();    }
 bool oopDesc::is_typeArray_noinline()   const { return is_typeArray();   }
 
 bool oopDesc::has_klass_gap() {
-  return UseCompressedClassPointers && !UseCompactObjectHeaders;
+  return ObjLayout::oop_has_klass_gap();
 }
 
 #if INCLUDE_CDS_JAVA_HEAP