re PR tree-optimization/45122 (-funsafe-loop-optimizations causes FAIL: gcc.c-torture/execute/pr27285.c execution)

gcc/ChangeLog:
PR tree-optimization/45122
* tree-ssa-loop-niter.c (number_of_iterations_exit): Don't make
unsafe assumptions when there's more than one loop exit.
gcc/testsuite/ChangeLog:
PR tree-optimization/45122
* gcc.dg/tree-ssa/pr45122.c: New.

From-SVN: r169781