Opaque OrdinalPool.getThreadR.

Lemma addThread_internal_step:
forall tp tp' m m' i vf arg pmap
(cnti: containsThread tp i)
(cnti': containsThread (addThread tp vf arg pmap) i)
(Hcomp: mem_compatible tp m)
(Hcomp': mem_compatible (addThread tp vf arg pmap) m)
(Hinv': invariant (addThread tp vf arg pmap))
(Hstep: internal_step cnti Hcomp tp' m'),
internal_step cnti' Hcomp' (addThread tp' vf arg pmap) m'.