[29/46] Use stmt_vec_info instead of gimple stmts internally (part 2)

[29/46] Use stmt_vec_info instead of gimple stmts internally (part 2)

This second part handles the less mechnical cases, i.e. those that don't
just involve swapping a gimple stmt for an existing stmt_vec_info.

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

gcc/
	* tree-vect-loop.c (vect_analyze_loop_operations): Look up the
	statement before passing it to vect_analyze_stmt.
	(vect_create_epilog_for_reduction): Use a stmt_vec_info to walk
	the chain of phi vector definitions.  Track the exit phi via its
	stmt_vec_info.
	(vectorizable_reduction): Set cond_stmt_vinfo directly from the
	STMT_VINFO_REDUC_DEF.
	* tree-vect-slp.c (vect_get_place_in_interleaving_chain): Use
	stmt_vec_infos to handle the statement chains.
	(vect_get_slp_defs): Record the first statement in the node
	using a stmt_vec_info.
	* tree-vect-stmts.c (vect_mark_stmts_to_be_vectorized): Look up
	statements here and pass their stmt_vec_info down to subroutines.
	(vect_init_vector_1): Hoist call to vinfo_for_stmt and pass it
	down to vect_finish_stmt_generation.
	(vect_init_vector, vect_get_vec_defs, vect_finish_replace_stmt)
	(vect_finish_stmt_generation): Call vinfo_for_stmt and pass
	stmt_vec_infos to subroutines.
	(vect_remove_stores): Use stmt_vec_infos to handle the statement
	chains.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@263144 138bc75d-0d04-0410-961f-82ee72b054a4