7009266: G1: assert(obj->is_oop_or_null(true )) failed: Error
Summary: 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
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#ifndef CPU_X86_VM_INTERPRETERGENERATOR_X86_HPP
#define CPU_X86_VM_INTERPRETERGENERATOR_X86_HPP
// Generation of Interpreter
//
friend class AbstractInterpreterGenerator;
private:
address generate_normal_entry(bool synchronized);
address generate_native_entry(bool synchronized);
address generate_abstract_entry(void);
address generate_method_handle_entry(void);
address generate_math_entry(AbstractInterpreter::MethodKind kind);
address generate_empty_entry(void);
address generate_accessor_entry(void);
address generate_Reference_get_entry();
void lock_method(void);
void generate_stack_overflow_check(void);
void generate_counter_incr(Label* overflow, Label* profile_method, Label* profile_method_continue);
void generate_counter_overflow(Label* do_continue);
#endif // CPU_X86_VM_INTERPRETERGENERATOR_X86_HPP