[Bug tree-optimization/85698] New: CPU2017 525.x264_r fails starting with r257581

[pthaugen at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85698

            Bug ID: 85698
           Summary: CPU2017 525.x264_r fails starting with r257581
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pthaugen at gcc dot gnu.org
                CC: rguenth at gcc dot gnu.org, segher at kernel dot 
crashing.org,
                    wschmidt at gcc dot gnu.org
  Target Milestone: ---
              Host: powerpc64le-unknown-linux-gnu
            Target: powerpc64le-unknown-linux-gnu
             Build: powerpc64le-unknown-linux-gnu

Benchmark miscompares starting with given revision. Options used for building
the benchmark are "-O3 -mcpu=power8". I did discover that adding -funroll-loops
changes behavior such that the benchmark passes.

Continuing to see if I can narrow down to a specific file that's miscompiled...