* tree-flow.h (loop_only_exit_p): Declare.
* tree-ssa-loop-niter.c (loop_only_exit_p): Make public.
* tree-ssa-loop-ivopts.c (may_eliminate_iv): Reinstate direct check on
the number of iterations if it is constant. Otherwise, if this is the
only possible exit of the loop, use the conservative estimate on the
number of iterations of the entire loop if available.
From-SVN: r137437
