[patch] lno branch merge - vectorizer patch #5

[Olga Golovanevsky <OLGA at il dot ibm dot com>]

Hi,

This patch enhances vectorizer with support of loops
with unaligned stores. Both cases are handled:
a store which alignment is unknown in compile time
and a store with known unalignment.

The patch is base on loop transformation introduced
in vectorizer patch #2
(http://gcc.gnu.org/ml/gcc-patches/2004-09/msg01104.html,
hopefully to be reviewed!)

Tested on powerpc-apple-darwin7.0.0. All vectorizer test
pass. Testcases 26 and 28 are changed from
xfail to pass; additional two loops are vectorized in
testcase 31.

The diff includes also vectorizer patch #2, while
ChangeLog is only for this patch.

thanks,
olga

ChengeLog:


        * tree-vectorizer.c (vect_get_loop_niters):
        (vect_gen_niters_for_prolog_loop):
        (vect_update_niters_after_peeling):
        (vect_update_inits_of_dr):
        (vect_update_inits_of_drs):
        (vect_do_peeling_for_alignment): New functions.
        (vect_transform_loop): Added unalignment support.
        (vect_analyze_data_refs_alignment): Allowed one unaligned
store.
        * tree-vectorizer.h (MAX_NUMBER_OF_UNALIGNED_DATA_REFS): New
define.
        (do_peeling_for_alignment):
        (unaligned_drs): New members of _loop_vec_info.
        (LOOP_DO_PEELING_FOR_ALIGNMENT): New macro.

(See attached file: peeling_main1.txt)

Attachment: peeling_main1.txt
Description: Text document