[ops] Replaced some dodgy constructs (direct VTABLE execution?) with cleaner and safer accessor macros.  No functional changes.
[ops] Replaced some dodgy constructs (direct VTABLE execution?) with cleaner
and safer accessor macros.  No functional changes.

git-svn-id: 6e74a02f85675cec270f5d931b0f6998666294a3@41249 d31e2699-5ff4-0310-a27c-f18f2fbe73fe

ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot