[patch] PR19951 fix (ICE in vectorizer)

[Dorit Naishlos <DORIT at il dot ibm dot com>]

We were attempting to split an abnormal edge.
Also realized we were assuming that a pre_header bb has a single successor,
which is not necessarily the case, so this is fixed too.

bootstrapped (with vectorization enabled) and tested (also on SPEC) on
powerpc-darwin

ok for mainline?

thanks

dorit

(p.s. I'd really like to commit the tree-vectorizer.c file splitup
(http://gcc.gnu.org/ml/gcc-patches/2005-02/msg00599.html) before committing
further patches to the vectorizer... would very much appreciate a review on
that one...)

Changelog:

      * tree-vectorizer.c (vect_analyze_loop_form): Don't split abnormal
edge.

Patch:
(See attached file: pr19951.patch)

Attachment: pr19951.patch
Description: Binary data