Summary: During the work for 6829187 we have fixed a number of basic bugs which are logically grouped with 6815692 and 6858164 but which must be reviewed and pushed separately.
Reviewed-by: kvn, never

Reviewed-by: jrose, kvn, cfang, twisti

Summary: Make a special root-list for those few nmethods which might contain non-perm oops.
Reviewed-by: twisti, kvn, never, jmasa, ysr

Summary: use PcDesc to keep record of the reexecute bit instead of using DebugInfoStreams
Reviewed-by: kvn, never, twisti

Summary: developed a reexecute logic for the interpreter to reexecute the bytecode when deopt happens
Reviewed-by: kvn, never, jrose, twisti