[Bug tree-optimization/21272] New: SSA_NAME def follows use with -ftree-vectorize

["janis at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

GCC mainline gets an internal compiler error compiling SPEC CPU2000
tests ammp, galgel, lucas, and twolf on powerpc64-linux with
"-O2 -ftree-vectorize -maltivec" and either -m32 or -m64, as shown
by this minimized testcase:
                                                                                
double
foo (int j, double *v, double x)
{
  int i;
  for (i = 0; i < j; i++)
    if (v[i] < x)
      x = v[i];
  return x;
}
                                                                                
elm3b145% /opt/gcc-nightly/mline-20050427/bin/gcc -m32 -O2 -ftree-vectorize
-maltivec -c bug.c
bug.c: In function ?foo?:
bug.c:3: error: Definition in block 2 follows the use
for SSA_NAME: i_15 in statement:
x_2 = j_6 > i_15 ? x_14 : x_23;
bug.c:3: internal compiler error: verify_ssa failed.
                                                                                
The failures start with this patch from dpatel:
                                                                                
  http://gcc.gnu.org/ml/gcc-cvs/2005-04/msg01172.html

-- 
           Summary: SSA_NAME def follows use with -ftree-vectorize
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: janis at gcc dot gnu dot org
                CC: dpatel at gcc dot gnu dot org,gcc-bugs at gcc dot gnu
                    dot org
 GCC build triplet: powerpc64-linux
  GCC host triplet: powerpc64-linux
GCC target triplet: powerpc64-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21272