How to get JS bytecode from JSD?

Hi,

I am trying to track precise execution of script and data flows by
using the JSD interface. I use jsdIDebuggerService.interruptHook to
register a hook function for execution of every bytecode instruction.
However, from what I receive at the hook function, I cannot determine
what instructions are being executed. I can get the line number and
the PC count, and together from the pretty-print of the jsdIScript
object, each line of script being executed can be obtained.

However, this is not always helpful. E.g., when a script has a loop of
a conditional branch, my callback function will not be notified of the
end of the loop or the branch.

Is there any way to obtain the bytecode of each jsdIScript object?
I appreciate your help.

Sachiko