Rename can_post_exceptions support to can_post_on_exceptions. Add support for should_post_on_exceptions flag to permit per JavaThread optimizations.
Reviewed-by: never, kvn, dcubed
C2 needs some additional optimizations to be able to handle MethodHandle invokes and invokedynamic instructions at the best performance.
Reviewed-by: kvn, never
Treat ProfileData in MDO's as a source of weak, not strong, roots. Fixes the bug for stop-world collection -- the case of concurrent collection will be fixed separately.
Reviewed-by: jcoomes, jmasa, kvn, never
