[Bug tree-optimization/56812] New: Simple loop is not SLP-vectorized after r196872

[ysrumyan at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56812



             Bug #: 56812

           Summary: Simple loop is not SLP-vectorized after r196872

    Classification: Unclassified

           Product: gcc

           Version: 4.9.0

            Status: UNCONFIRMED

          Severity: normal

          Priority: P3

         Component: tree-optimization

        AssignedTo: unassig...@gcc.gnu.org

        ReportedBy: ysrum...@gmail.com





A simple loop in attached test-case is not SLP-vectorized after this fix with

message:



t.cc:12: note: can't determine dependence between this_4(D)->data[0] and

this_4(D)->data[i_14]

t.cc:12: note: not vectorized: unhandled data dependence in basic block.



To reproduce the failure it is sufficient to compile this test on x86 with the

following options:

  -O3 -funroll-loops -march=IVB