Optimize condition reductions where the result is an integer induction variable

Optimize condition reductions where the result is an integer induction variable

2015-11-13  Alan Hayward <alan.hayward@arm.com>

gcc/
	PR tree-optimization/66558
	* tree-vect-loop.c (is_integer_induction):Add.
	(vectorizable_reduction): Add integer induction checks.

gcc/testsuite/
	PR tree-optimization/66558
	* gcc.dg/vect/pr65947-1.c: Add checks.
	* gcc.dg/vect/pr65947-2.c: Add checks.
	* gcc.dg/vect/pr65947-3.c: Add checks.
	* gcc.dg/vect/pr65947-4.c: Add checks.
	* gcc.dg/vect/pr65947-5.c: Add checks.
	* gcc.dg/vect/pr65947-6.c: Add checks.
	* gcc.dg/vect/pr65947-10.c: Add checks.
	* gcc.dg/vect/pr65947-12.c: New test.
	* gcc.dg/vect/pr65947-13.c: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@230297 138bc75d-0d04-0410-961f-82ee72b054a4