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