re PR tree-optimization/18181 (vectorizer: problem in the peeling mechanism in the...

re PR tree-optimization/18181 (vectorizer: problem in the peeling mechanism in the presence of loop invariants that are used after the loop)

        PR tree-opt/18181
        * tree-vectorizer.c (slpeel_tree_peel_loop_to_edge): Peeling scheme
        changed to suppoer uses-after-loop and to void creating flow paths
        that shouldn't exist.
        (slpeel_update_phi_nodes_for_guard): Takes additional two arguments.
        Modified to fit the new peeling scheme. Avoid quadratic behavior.
        (slpeel_add_loop_guard): Takes additional argument.
        (slpeel_verify_cfg_after_peeling): New function.
        (vect_update_ivs_after_vectorizer): Takes additional argument. Updated
        documentation. Use 'exit-bb' instead of creating 'new-bb'.
        (rename_variables_in_bb): Don't update phis for BBs out of loop, to fit
        the new peeling scheme.
        (copy_phi_nodes): Function removed. Its functionality moved to
        update_phis_for_duplicate_loop.
        (slpeel_update_phis_for_duplicate_loop): Functionality of copy_phi_nodes
        moved here. Added documentation. Modified to fit the new peeling scheme.
        (slpeel_make_loop_iterate_ntimes): Setting loop->single_exit not not
        needed - done in slpeel_tree_peel_loop_to_edge.
        (slpeel_tree_duplicate_loop_to_edge_cfg): Debug printouts compacted.
        (vect_do_peeling_for_loop_bound): Add documentation. Call
        slpeel_verify_cfg_after_peeling. Call vect_update_ivs_after_vectorizer
        with additional argument.
        (vect_do_peeling_for_alignment): Call slpeel_verify_cfg_after_peeling.

        (vect_finish_stmt_generation): Avoid 80 column oveflow.

From-SVN: r90932