[Bug tree-optimization/37573] New: gcc-4.4 regression: incorrect code generation with -O1 -ftree-vectorize

["edwintorok at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

Compiling the testcase below with -O2 works, and fails with -O3.
gcc-4.3 works with both -O2 and -O3.

$ x86_64-unknown-linux-gnu-gcc-4.4.0 -O2 testcase-min.i
$ ./a.out
OK
$ x86_64-unknown-linux-gnu-gcc-4.4.0 -O3 testcase-min.i
$ ./a.out
Failed:
/.G����7��G��?�?�;
$ ./a.out
Failed: �G����7
h�G��3�?�

$ gcc-4.3 -O3 testcase-min.i
$ ./a.out
OK

Actually it is -ftree-vectorize that causes the failure:

$ x86_64-unknown-linux-gnu-gcc-4.4.0 -O1 -ftree-vectorize testcase-min.i
$ ./a.out
Failed:"�@���@ �?��

The output is random garbage with -O3, but should be '>AUTOIT UNICODE SCRIPT<'.

$ x86_64-unknown-linux-gnu-gcc-4.4.0 --version
x86_64-unknown-linux-gnu-gcc-4.4.0 (GCC) 4.4.0 20080918 (experimental)
Copyright (C) 2008 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

gcc-4.4 is a build from svn:
$ svn info
Path: .
URL: svn://gcc.gnu.org/svn/gcc/trunk
Repository Root: svn://gcc.gnu.org/svn/gcc
Repository UUID: 138bc75d-0d04-0410-961f-82ee72b054a4
Revision: 140456
Node Kind: directory
Schedule: normal
Last Changed Author: amacleod
Last Changed Rev: 140456
Last Changed Date: 2008-09-18 17:07:35 +0300 (Thu, 18 Sep 2008)

$ gcc-4.3 --version
gcc-4.3 (Debian 4.3.2-1) 4.3.2
Copyright (C) 2008 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.


-- 
           Summary: gcc-4.4 regression: incorrect code generation with -O1 -
                    ftree-vectorize
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: edwintorok at gmail dot com
 GCC build triplet: x86_64-unknown-linux-gnu-gcc-4.4.0
  GCC host triplet: x86_64-unknown-linux-gnu-gcc-4.4.0
GCC target triplet: x86_64-unknown-linux-gnu-gcc-4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37573