Corollary find_funct_ptr_inversion:
  forall p b f,
  find_funct_ptr (globalenv p) b = Some f ->
  exists id, In (id, Gfun f) (prog_defs p).Corollary find_funct_inversion:
  forall p v f,
  find_funct (globalenv p) v = Some f ->
  exists id, In (id, Gfun f) (prog_defs p).

Theorem invert_find_symbol: forall ge id b, invert_symbol ge b = Some id -> find_symbol ge id = Some b.