7009266: G1: assert(obj->is_oop_or_null(true )) failed: Error

A referent object that is only weakly reachable at the start of concurrent marking but is re-attached to the strongly reachable object graph during marking may not be marked as live. This can cause the reference object to be processed prematurely and leave dangling pointers to the referent object. Implement a read barrier for the java.lang.ref.Reference::referent field by intrinsifying the Reference.get() method, and intercepting accesses though JNI, reflection, and Unsafe, so that when a non-null referent object is read it is also logged in an SATB buffer.

Reviewed-by: kvn, iveresov, never, tonyp, dholmes
This commit is contained in:
John Cuthbertson 2011-04-07 09:53:20 -07:00
parent aac4647e6e
commit a08e1ce906
41 changed files with 1423 additions and 268 deletions

View file

@ -403,6 +403,8 @@ class instanceKlass: public Klass {
ReferenceType reference_type() const { return _reference_type; }
void set_reference_type(ReferenceType t) { _reference_type = t; }
static int reference_type_offset_in_bytes() { return offset_of(instanceKlass, _reference_type); }
// find local field, returns true if found
bool find_local_field(Symbol* name, Symbol* sig, fieldDescriptor* fd) const;
// find field in direct superinterfaces, returns the interface in which the field is defined