On Tue, 18 Jan 2022, Andre Vieira (lists) wrote: > > On 14/01/2022 09:57, Richard Biener wrote: > > > > The 'used_vector_modes' is also a heuristic by itself since it registers > > every vector type we query, not only those that are used in the end ... > > > > So it's really all heuristics that can eventually go bad. > > > > IMHO remembering the VF that we ended up with (maybe w/o unrolling) > > for each analyzed vector_mode[] might be really the easiest thing to do, > > that should make it easy to skip those modes where the VF is larger > > or equal as the VF of the main loop for the purpose of epilogue > > vectorization. Likewise those vector_mode[] that failed analysis can > > be remembered (with -1U VF for example). > > > > Richard. > > I liked the caching suggestion, so here it is. Sorry for the delay, wanted to > post this after pushing the vect unroll which was waiting on some retesting > for the rebase.
LGTM. Thanks, Richard. > gcc/ChangeLog: > > PR 103997 > * tree-vect-loop.c (vect_analyze_loop): Fix mode skipping for > epilogue > vectorization. >
