src/hotspot/share/oops/access.hpp

@@ -55,10 +55,11 @@
  // * atomic_cmpxchg_at: Atomically compare-and-swap a new value at an internal pointer address if previous value matched the compared value.
  // * atomic_xchg: Atomically swap a new value at an address if previous value matched the compared value.
  // * atomic_xchg_at: Atomically swap a new value at an internal pointer address if previous value matched the compared value.
  // * arraycopy: Copy data from one heap array to another heap array. The ArrayAccess class has convenience functions for this.
  // * clone: Clone the contents of an object to a newly allocated object.
+ // * value_copy: Copy the contents of a value type from one heap address to another
  //
  // == IMPLEMENTATION ==
  // Each access goes through the following steps in a template pipeline.
  // There are essentially 5 steps for each access:
  // * Step 1:   Set default decorators and decay types. This step gets rid of CV qualifiers

@@ -88,10 +89,12 @@
  // Steps 5.a and 5.b require knowledge about the GC backends, and therefore needs to
  // include the various GC backend .inline.hpp headers. Their implementation resides in
  // access.inline.hpp. The accesses that are allowed through the access.hpp file
  // must be instantiated in access.cpp using the INSTANTIATE_HPP_ACCESS macro.
  
+ class InlineKlass;
+ 
  template <DecoratorSet decorators = DECORATORS_NONE>
  class Access: public AllStatic {
    // This function asserts that if an access gets passed in a decorator outside
    // of the expected_decorators, then something is wrong. It additionally checks
    // the consistency of the decorators so that supposedly disjoint decorators are indeed

@@ -120,25 +123,31 @@
      const DecoratorSet heap_oop_decorators = AS_DECORATOR_MASK | ON_DECORATOR_MASK |
                                               IN_HEAP | IS_ARRAY | IS_NOT_NULL | IS_DEST_UNINITIALIZED;
      verify_decorators<expected_mo_decorators | heap_oop_decorators>();
    }
  
+   template <DecoratorSet expected_mo_decorators>
+   static void verify_heap_value_decorators() {
+     const DecoratorSet heap_value_decorators = IN_HEAP | IS_DEST_UNINITIALIZED;
+     verify_decorators<expected_mo_decorators | heap_value_decorators>();
+   }
+ 
    static const DecoratorSet load_mo_decorators = MO_UNORDERED | MO_RELAXED | MO_ACQUIRE | MO_SEQ_CST;
    static const DecoratorSet store_mo_decorators = MO_UNORDERED | MO_RELAXED | MO_RELEASE | MO_SEQ_CST;
    static const DecoratorSet atomic_xchg_mo_decorators = MO_SEQ_CST;
    static const DecoratorSet atomic_cmpxchg_mo_decorators = MO_RELAXED | MO_SEQ_CST;
  
  protected:
    template <typename T>
-   static inline bool oop_arraycopy(arrayOop src_obj, size_t src_offset_in_bytes, const T* src_raw,
+   static inline void oop_arraycopy(arrayOop src_obj, size_t src_offset_in_bytes, const T* src_raw,
                                     arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,
                                     size_t length) {
      verify_decorators<ARRAYCOPY_DECORATOR_MASK | IN_HEAP |
                        AS_DECORATOR_MASK | IS_ARRAY | IS_DEST_UNINITIALIZED>();
-     return AccessInternal::arraycopy<decorators | INTERNAL_VALUE_IS_OOP>(src_obj, src_offset_in_bytes, src_raw,
-                                                                          dst_obj, dst_offset_in_bytes, dst_raw,
-                                                                          length);
+     AccessInternal::arraycopy<decorators | INTERNAL_VALUE_IS_OOP>(src_obj, src_offset_in_bytes, src_raw,
+                                                                   dst_obj, dst_offset_in_bytes, dst_raw,
+                                                                   length);
    }
  
    template <typename T>
    static inline void arraycopy(arrayOop src_obj, size_t src_offset_in_bytes, const T* src_raw,
                                 arrayOop dst_obj, size_t dst_offset_in_bytes, T* dst_raw,

@@ -210,10 +219,18 @@
    static inline void clone(oop src, oop dst, size_t size) {
      verify_decorators<IN_HEAP>();
      AccessInternal::clone<decorators>(src, dst, size);
    }
  
+   // inline type heap access (when flat)...
+ 
+   // Copy value type data from src to dst
+   static inline void value_copy(void* src, void* dst, InlineKlass* md) {
+     verify_heap_value_decorators<IN_HEAP>();
+     AccessInternal::value_copy<decorators>(src, dst, md);
+   }
+ 
    // Primitive accesses
    template <typename P>
    static inline P load(P* addr) {
      verify_primitive_decorators<load_mo_decorators>();
      return AccessInternal::load<decorators, P, P>(addr);

@@ -320,23 +337,23 @@
      AccessT::arraycopy(nullptr, 0, src,
                         dst_obj, dst_offset_in_bytes, static_cast<T*>(nullptr),
                         length);
    }
  
-   static inline bool oop_arraycopy(arrayOop src_obj, size_t src_offset_in_bytes,
+   static inline void oop_arraycopy(arrayOop src_obj, size_t src_offset_in_bytes,
                                     arrayOop dst_obj, size_t dst_offset_in_bytes,
                                     size_t length) {
-     return AccessT::oop_arraycopy(src_obj, src_offset_in_bytes, static_cast<const HeapWord*>(nullptr),
-                                   dst_obj, dst_offset_in_bytes, static_cast<HeapWord*>(nullptr),
-                                   length);
+     AccessT::oop_arraycopy(src_obj, src_offset_in_bytes, static_cast<const HeapWord*>(nullptr),
+                            dst_obj, dst_offset_in_bytes, static_cast<HeapWord*>(nullptr),
+                            length);
    }
  
    template <typename T>
-   static inline bool oop_arraycopy_raw(T* src, T* dst, size_t length) {
-     return AccessT::oop_arraycopy(nullptr, 0, src,
-                                   nullptr, 0, dst,
-                                   length);
+   static inline void oop_arraycopy_raw(T* src, T* dst, size_t length) {
+     AccessT::oop_arraycopy(nullptr, 0, src,
+                            nullptr, 0, dst,
+                            length);
    }
  
  };
  
  template <DecoratorSet decorators>