From 4e9b2c94e45f5991a472fb639fb2baa6aa42b76b Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Thu, 14 Dec 2023 16:00:50 +0100 Subject: [PATCH] tree-optimization/113018 - ICE with BB reduction vectorization When BB reduction vectorization picks up a chain with an ASM def in it and that's inside the vectorized region we fail to get its LHS. Instead of trying to get the correct def the following avoids vectorizing such def and instead keeps it as def to add in the epilog. PR tree-optimization/113018 * tree-vect-slp.cc (vect_slp_check_for_roots): Only start SLP discovery from stmts with a LHS. --- gcc/tree-vect-slp.cc | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc index f8a168caa600..a82fca451610 100644 --- a/gcc/tree-vect-slp.cc +++ b/gcc/tree-vect-slp.cc @@ -7419,7 +7419,12 @@ vect_slp_check_for_roots (bb_vec_info bb_vinfo) invalid = true; break; } - if (chain[i].dt != vect_internal_def) + if (chain[i].dt != vect_internal_def + /* Avoid stmts where the def is not the LHS, like + ASMs. */ + || (gimple_get_lhs (bb_vinfo->lookup_def + (chain[i].op)->stmt) + != chain[i].op)) remain_cnt++; } if (!invalid && chain.length () - remain_cnt > 1) @@ -7431,8 +7436,11 @@ vect_slp_check_for_roots (bb_vec_info bb_vinfo) remain.create (remain_cnt); for (unsigned i = 0; i < chain.length (); ++i) { - if (chain[i].dt == vect_internal_def) - stmts.quick_push (bb_vinfo->lookup_def (chain[i].op)); + stmt_vec_info stmt_info; + if (chain[i].dt == vect_internal_def + && ((stmt_info = bb_vinfo->lookup_def (chain[i].op)), + gimple_get_lhs (stmt_info->stmt) == chain[i].op)) + stmts.quick_push (stmt_info); else remain.quick_push (chain[i].op); } -- 2.47.2