[Bug c/22198] New: Miscompile of SSE2 _mm_madd_epi16 with -O2

["hurbain at cri dot ensmp dot fr" <gcc-bugzilla at gcc dot gnu dot org>]

The attached code is OK with gcc 3.3.6 debian and gcc 4.0 without -O2 but does not generate pmaddw 
instruction with gcc 4.0 and -O2.
The compile line is
/usr/local/bin/gcc -save-temps -msse2 -Wall -O2 -o bug-report bug-report.c
and the values are NOT initialized in the gcc 4.0 -O2 setup.

-- 
           Summary: Miscompile of SSE2 _mm_madd_epi16 with -O2
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: hurbain at cri dot ensmp dot fr
                CC: gcc-bugs at gcc dot gnu dot org
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22198