> The following simply removes a seemingly bogus guard. > > * tree-vect-loop.cc (vect_analyze_loop_1): Remove SLP guard > from .SELECT_VL disabling. > --- > gcc/tree-vect-loop.cc | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc > index cc15492f6a0..378e7c560bd 100644 > --- a/gcc/tree-vect-loop.cc > +++ b/gcc/tree-vect-loop.cc > @@ -3078,7 +3078,7 @@ start_over: > if (direct_internal_fn_supported_p (IFN_SELECT_VL, iv_type, > OPTIMIZE_FOR_SPEED) > && LOOP_VINFO_LENS (loop_vinfo).length () == 1 > - && LOOP_VINFO_LENS (loop_vinfo)[0].factor == 1 && !slp > + && LOOP_VINFO_LENS (loop_vinfo)[0].factor == 1
I don't think it will just work like that. The problem is that we adjust data pointer increments according to the current vector length in vect_get_loop_variant_data_ptr_increment. To this end we use the SELECT_VL result and multiply it with the current dataref's step. Without having looked into it closer I suppose using step is not suffcient or maybe even wrong in an SLP setting and I guess this complication lead to SLP being disabled initially. -- Regards Robin
