Use max_loop_iterations in transform_to_exit_first_loop_alt

Use max_loop_iterations in transform_to_exit_first_loop_alt

2015-06-30  Tom de Vries  <tom@codesourcery.com>

	PR tree-optimization/66652
	* tree-parloops.c (try_transform_to_exit_first_loop_alt): Use
	max_loop_iterations to determine if nit + 1 overflows.

	* testsuite/libgomp.c/parloops-exit-first-loop-alt-3.c (f): Rewrite
	using restrict pointers.
	(main): Add arguments to calls to f.
	* testsuite/libgomp.c/parloops-exit-first-loop-alt.c: Same.

	* gcc.dg/parloops-exit-first-loop-alt-pr66652.c: New test.
	* gcc.dg/parloops-exit-first-loop-alt-3.c (f):  Rewrite using restrict
	pointers.
	* gcc.dg/parloops-exit-first-loop-alt.c: Same.

From-SVN: r225162