Wrong Insertion Method

I finally found the problem why the boolean $$$oldThread$$$ flag wasn’t sticking: I seemed to set it to false, but the next time I looked at it, it was true again.

The Java code basically is this:

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public static synchronized void compactWait(long code, long tid) {
if (!_replaying) {
return;
}

monitorEnter(_waitAlgoObj);

if (isOldThread()) {
// If this is NOT the first sync point for this thread...
...
}
else {
// Otherwise, if it was the first time... set flag.
setOldThread();
...
}

// More code...
...

monitorEnter(), isOldThread() and setOldThread() are dummy marker methods and get replaced with bytecode during instrumentation:

monitorEnter() becomes just a

GeSHi Error: GeSHi could not find the language jvm (using path /home/dh_8dhf9b/concurrentaffair.org/wp-content/plugins/codecolorer/lib/geshi/) (code 2)
isOldThread() becomes

GeSHi Error: GeSHi could not find the language jvm (using path /home/dh_8dhf9b/concurrentaffair.org/wp-content/plugins/codecolorer/lib/geshi/) (code 2)
setOldThread() becomes

GeSHi Error: GeSHi could not find the language jvm (using path /home/dh_8dhf9b/concurrentaffair.org/wp-content/plugins/codecolorer/lib/geshi/) (code 2)

The Java code above roughly corresponds to this bytecode:

GeSHi Error: GeSHi could not find the language jvm (using path /home/dh_8dhf9b/concurrentaffair.org/wp-content/plugins/codecolorer/lib/geshi/) (code 2)

My faulty instrumentation of the marker methods, however, generated this bytecode:

GeSHi Error: GeSHi could not find the language jvm (using path /home/dh_8dhf9b/concurrentaffair.org/wp-content/plugins/codecolorer/lib/geshi/) (code 2)

I was inserting the correct bytecode, but I was modifying call targets it in a way such that calls to the insertion location would go to the opcode just PAST the inserted code, whereas it should have gone right TO the inserted code. Now I can move on and face new, exciting problems