remove STMT_VINFO_NUM_SLP_USES

remove STMT_VINFO_NUM_SLP_USES

This removes STMT_VINFO_NUM_SLP_USES by pushing the setting of
the shared stmt_vec_info vector type to where we actually need it
which is alignment analysis and vectorizable_* analysis (where
we could eventually elide it for non-load/store operations).

In particular "uses" in the cache and in disqualified SLP
subgraphs should no longer provide conflicting vector types
this way.

2020-09-16  Richard Biener  <rguenther@suse.de>

	* tree-vectorizer.h (_stmt_vec_info::num_slp_uses): Remove.
	(STMT_VINFO_NUM_SLP_USES): Likewise.
	(vect_free_slp_instance): Adjust.
	(vect_update_shared_vectype): Declare.
	* tree-vectorizer.c (vec_info::~vec_info): Adjust.
	* tree-vect-loop.c (vect_analyze_loop_2): Likewise.
	(vectorizable_live_operation): Use vector type from
	SLP_TREE_REPRESENTATIVE.
	(vect_transform_loop): Adjust.
	* tree-vect-data-refs.c (vect_slp_analyze_node_alignment):
	Set the shared vector type.
	* tree-vect-slp.c (vect_free_slp_tree): Remove final_p
	parameter, remove STMT_VINFO_NUM_SLP_USES updating.
	(vect_free_slp_instance): Adjust.
	(vect_create_new_slp_node): Remove STMT_VINFO_NUM_SLP_USES
	updating.
	(vect_update_shared_vectype): Always compare with the
	present vector type, update if NULL.
	(vect_build_slp_tree_1): Do not update the shared vector
	type here.
	(vect_build_slp_tree_2): Adjust.
	(slp_copy_subtree): Likewise.
	(vect_attempt_slp_rearrange_stmts): Likewise.
	(vect_analyze_slp_instance): Likewise.
	(vect_analyze_slp): Likewise.
	(vect_slp_analyze_node_operations_1): Update the shared
	vector type.
	(vect_slp_analyze_operations): Adjust.
	(vect_slp_analyze_bb_1): Likewise.