On Wed, May 19, 2021 at 8:20 AM Kewen.Lin <li...@linux.ibm.com> wrote: > > Hi, > > This patch is to replace the current hardcoded weight factor 50 > for those statements in an inner loop relative to the loop being > vectorized with a specific parameter vect-inner-loop-weight-factor. > > The motivation behind this change is: if targets want to have one > unique function to gather some information in each add_stmt_cost > call, no matter that it's put before or after the cost tweaking > part for inner loop, it may have the need to adjust (expand or > shrink) the gathered data as the factor. Now the factor is > hardcoded, it's not easily maintained. Since it's possible that > targets have their own decisions on this costing like the others, > I used parameter instead of one unique macro here. > > Testing is ongoing, is it ok for trunk if everything goes well?
Certainly an improvement. I suppose we might want to put the factor into vinfo->inner_loop_cost_factor. That way we could adjust it easily in common code in the vectorizer when we for example have (non-guessed) profile data. "weight_factor" is kind-of double-speak and I'm missing 'cost' ... so, bike-shedding to vect_inner_loop_cost_factor? Just suggestions - as said, the patch is an improvement already. Thanks, Richard. > BR, > Kewen > ------- > gcc/ChangeLog: > > * doc/invoke.texi (vect-inner-loop-weight-factor): Document new > parameter. > * params.opt (vect-inner-loop-weight-factor): New. > * config/aarch64/aarch64.c (aarch64_add_stmt_cost): Replace hardcoded > weight factor 50 with param_vect_inner_loop_weight_factor. > * config/arm/arm.c (arm_add_stmt_cost): Likewise. > * config/i386/i386.c (ix86_add_stmt_cost): Likewise. > * config/rs6000/rs6000.c (rs6000_add_stmt_cost): Likewise. > * targhooks.c (default_add_stmt_cost): Likewise. > * tree-vect-loop.c (vect_compute_single_scalar_iteration_cost): > Likewise.
