From f3dbd3f36d55178d0a9e4431043cbc950524969a Mon Sep 17 00:00:00 2001 From: Kewen Lin Date: Mon, 25 Oct 2021 21:05:02 -0500 Subject: [PATCH] vect: Don't update inits for simd_lane_access DRs [PR102789] As PR102789 shows, when vectorizer does some peelings for alignment in prologues, function vect_update_inits_of_drs would update the inits of some drs. But as the failed case, we shouldn't update the dr for simd_lane_access, it has the fixed-length storage mainly for the main loop, the update can make the access out of bound and access the unexpected element. gcc/ChangeLog: PR tree-optimization/102789 * tree-vect-loop-manip.c (vect_update_inits_of_drs): Do not update inits of simd_lane_access. --- gcc/tree-vect-loop-manip.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/gcc/tree-vect-loop-manip.c b/gcc/tree-vect-loop-manip.c index 4988c93..378b102 100644 --- a/gcc/tree-vect-loop-manip.c +++ b/gcc/tree-vect-loop-manip.c @@ -1820,7 +1820,8 @@ vect_update_inits_of_drs (loop_vec_info loop_vinfo, tree niters, FOR_EACH_VEC_ELT (datarefs, i, dr) { dr_vec_info *dr_info = loop_vinfo->lookup_dr (dr); - if (!STMT_VINFO_GATHER_SCATTER_P (dr_info->stmt)) + if (!STMT_VINFO_GATHER_SCATTER_P (dr_info->stmt) + && !STMT_VINFO_SIMD_LANE_ACCESS_P (dr_info->stmt)) vect_update_init_of_dr (dr_info, niters, code); } } -- 2.7.4