[11/46] Pass back a stmt_vec_info from vect_is_simple_use

[11/46] Pass back a stmt_vec_info from vect_is_simple_use

This patch makes vect_is_simple_use pass back a stmt_vec_info to
those callers that want it.  Most users only need the stmt_vec_info
but some need the gimple stmt too.

It's probably high time we added a class to represent "simple operands"
instead, but I have a separate series that tries to clean up how
operands are handled (with a view to allowing mixed vector sizes).

2018-07-31  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* tree-vectorizer.h (vect_is_simple_use): Add an optional
	stmt_vec_info * parameter before the optional gimple **.
	* tree-vect-stmts.c (vect_is_simple_use): Likewise.
	(process_use, vect_get_vec_def_for_operand_1): Update callers.
	(vect_get_vec_def_for_operand, vectorizable_shift): Likewise.
	* tree-vect-loop.c (vectorizable_reduction): Likewise.
	(vectorizable_live_operation): Likewise.
	* tree-vect-patterns.c (type_conversion_p): Likewise.
	(vect_look_through_possible_promotion): Likewise.
	(vect_recog_rotate_pattern): Likewise.
	* tree-vect-slp.c (vect_get_and_check_slp_defs): Likewise.

From-SVN: r263126