RuntimeHelper.checkRestricted adding 25X overhead to antlr parsing on GAE Java 1.7

[Marc Hacker]

We are using antlr parsing on GAE 1.7 and find a 25x overhead running on GAE v. standalone Java app because it spends 96% of its time in RuntimeHelper.checkRestricted()!!

(We are NOT in GAE 1.6.4 which had a bug of extra calls to RuntimeHelper.checkRestricted)

Does anyone know a list of which method calls trigger calls to RuntimeHelper.checkRestricted so that we can potentially avoid those please? For some reason I can't find any documentation of this security manager and what triggers it.

One call which repeatedly triggers a time-consuming call to checkRestricted seems to be antlr.runtime.DFA.predict(IntStream)

How can we avoid this impossibly big security overhead please - thanks!

Thanks!