On Tue, Apr 11, 2017 at 4:03 PM, Robin Dapp <rd...@linux.vnet.ibm.com> wrote: > Hi Bin, > >> Seems Richi added code like below comparing costs between aligned and >> unsigned loads, and only peeling if it's beneficial: >> >> /* In case there are only loads with different unknown misalignments, >> use >> peeling only if it may help to align other accesses in the loop or >> if it may help improving load bandwith when we'd end up using >> unaligned loads. */ >> tree dr0_vt = STMT_VINFO_VECTYPE (vinfo_for_stmt (DR_STMT (dr0))); >> if (!first_store >> && !STMT_VINFO_SAME_ALIGN_REFS ( >> vinfo_for_stmt (DR_STMT (dr0))).length () >> && (vect_supportable_dr_alignment (dr0, false) >> != dr_unaligned_supported >> || (builtin_vectorization_cost (vector_load, dr0_vt, 0) >> == builtin_vectorization_cost (unaligned_load, dr0_vt, -1)))) >> do_peeling = false; > > yes this is the "special case" I was referring to. This successfully > avoids peeling when there is no store (after we had set vectorization > costs). My patch tries to check the costs for all references. I am not sure if all references need to be checked, on AArch64, aligned/unaligned costs are set globally, so only need to make one check here.
Thanks, bin > > Regards > Robin >
