[gclist] write-barrier implementation in Java VM?

Okehee Goh ogoh@cise.ufl.edu
Mon, 6 Nov 2000 01:25:07 -0500


I'd like to ask about incremental GC of Java VM.
I recently implemented incremental GC on KVM, SunMicrosystem's VM for
embedded
 or resource limited system.
I just simplified works for doing this job because my goal is not generating
 most efficient incremental GC of JVM. This is intermediate step for other
experiment.
Even though it is, I'm worrying if what I did for incremental GC are correct
or not.

 I put write-barrier on the interpret codes for PUTFIELD, PUTFILED_FAST,
PUTSTATIC, and PUTSTATIC_FAST when they are executed during the garbage
collection cycle.
If resolved field's type of object is reference, those object is pushed to a
stack for
 later stage of mark according to marking status of source object and target
object.

What I am worrying is if those are only bytecode operations whose
write-barrier are required. Are there any other part or bytecode operations
where write-barrier must
be applied ?

I appreciate any your comments.

Thank you very much.

Okehee

 ********************************************************************
 Okehee Goh        ogoh@cise.ufl.edu   http://www.cise.ufl.edu/~ogoh
 RealTime System Lab.  (T) 1-352-392-6875
 CISE Dept.  University Of Florida