Vectorize mult expressions with power 2 constants via shift, for targets has no vector multiplication support.

 
2015-08-06  Venkataramanan Kumar  <Venkataramanan.kumar@amd.com>

	* tree-vect-patterns.c (vect_recog_mult_pattern): New function
	for vectorizing multiplication patterns.
	* tree-vectorizer.h: Adjust the number of patterns.

2015-08-06  Venkataramanan Kumar  <Venkataramanan.kumar@amd.com>

	* gcc.dg/vect/vect-mult-pattern-1.c: New test.
	* gcc.dg/vect/vect-mult-pattern-2.c: New test.

From-SVN: r226675