[Bug rtl-optimization/46614] New: [4.5/4.6 Regression] gcc.dg/vect/vect-strided-u8-i8-gap4.c FAILs with -fno-rename-registers -fsched2-use-superblocks

["zsojka at seznam dot cz" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46614

           Summary: [4.5/4.6 Regression]
                    gcc.dg/vect/vect-strided-u8-i8-gap4.c FAILs with
                    -fno-rename-registers -fsched2-use-superblocks
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: zsojka@seznam.cz
              Host: x86_64-pc-linux-gnu
            Target: x86_64-pc-linux-gnu


Flags:
-O2 -fno-rename-registers -fsched2-use-superblocks -ftree-vectorize
-funroll-loops
or
-O -fgcse -fno-rename-registers -fsched2-use-superblocks -fschedule-insns2
-ftree-vectorize -funroll-all-loops

Output:
$ gcc -O -fgcse -fno-rename-registers -fsched2-use-superblocks
-fschedule-insns2 -ftree-vectorize -funroll-loops vect-strided-u8-i8-gap4.i
$ valgrind -q ./a.out 
==7908== Conditional jump or move depends on uninitialised value(s)
==7908==    at 0x400CBB: main1 (vect-strided-u8-i8-gap4.c:45)
==7908==    by 0x401862: main (vect-strided-u8-i8-gap4.c:96)
==7908== 
Aborted

Tested revisions:
r167054 - fail
r158095 - fail
r153685 - OK
4.5 r166509 - fail
4.4 r166509 - OK