setOldThread and isOldThread

The instrumentation should actually be pretty easy. I just looked at the bytecode of this class:

and the main method contains these instructions:

The invokestatic Test.isOldThread()Z puts the return value on the stack. The ifeq jumps over the then block if the return value was false; the goto in line 4 jumps over the else block if it was true and the then block has already been executed.

This just needs to be turned into

The old line 1 gets replaced by the new lines 1 and 2, which get the current thread, and then get its
GeSHi Error: GeSHi could not find the language jvm (using path /homepages/42/d86928234/htdocs/blog/wp-content/plugins/codecolorer/lib/geshi/) (code 2)
field.

The old line 5 gets replaced by the new lines 6 to 8, which put
GeSHi Error: GeSHi could not find the language jvm (using path /homepages/42/d86928234/htdocs/blog/wp-content/plugins/codecolorer/lib/geshi/) (code 2)
on the stack, get the current thread, and then set its
GeSHi Error: GeSHi could not find the language jvm (using path /homepages/42/d86928234/htdocs/blog/wp-content/plugins/codecolorer/lib/geshi/) (code 2)
field.


GeSHi Error: GeSHi could not find the language jvm (using path /homepages/42/d86928234/htdocs/blog/wp-content/plugins/codecolorer/lib/geshi/) (code 2)
and
GeSHi Error: GeSHi could not find the language jvm (using path /homepages/42/d86928234/htdocs/blog/wp-content/plugins/codecolorer/lib/geshi/) (code 2)
are even easier to handle.

just has to be changed into

Exactly the same applies for
GeSHi Error: GeSHi could not find the language jvm (using path /homepages/42/d86928234/htdocs/blog/wp-content/plugins/codecolorer/lib/geshi/) (code 2)
. The value on top of the stack isn’t used as first parameter anymore, now it’s directly consumed by the
GeSHi Error: GeSHi could not find the language jvm (using path /homepages/42/d86928234/htdocs/blog/wp-content/plugins/codecolorer/lib/geshi/) (code 2)
or
GeSHi Error: GeSHi could not find the language jvm (using path /homepages/42/d86928234/htdocs/blog/wp-content/plugins/codecolorer/lib/geshi/) (code 2)
instruction.