From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1666) id B0C1C3856967; Mon, 17 Oct 2022 13:10:54 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B0C1C3856967 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1666012254; bh=mJP5epNcOtDxabX+usCoALGoihzYxClbygVoQE14HLo=; h=From:To:Subject:Date:From; b=p6Uxa3Vu2wpYsHh10GaBL2pDCgqZr8swRmipaj/0/OOBz8ZOXtldJGBveV3GVpzSW yvfkYUXgoF7CEdc95Wc2QDH5Kquy54bHD2+4+viCanQElcXWhEnq+qSKMo0e05QqYt gVVqyv/85tWK8RCbPRNarbpM0N1z6lRdr0rBfQrI= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Richard Biener To: gcc-cvs@gcc.gnu.org Subject: [gcc r12-8840] tree-optimization/107212 - SLP reduction of reduction paths X-Act-Checkin: gcc X-Git-Author: Richard Biener X-Git-Refname: refs/heads/releases/gcc-12 X-Git-Oldrev: d282dd56275485a88e1fe9c4ae1939b62d23b20b X-Git-Newrev: d127348d7711e148e5ddd205a8c3409b37fae64c Message-Id: <20221017131054.B0C1C3856967@sourceware.org> Date: Mon, 17 Oct 2022 13:10:54 +0000 (GMT) List-Id: https://gcc.gnu.org/g:d127348d7711e148e5ddd205a8c3409b37fae64c commit r12-8840-gd127348d7711e148e5ddd205a8c3409b37fae64c Author: Richard Biener Date: Tue Oct 11 11:34:55 2022 +0200 tree-optimization/107212 - SLP reduction of reduction paths The following fixes an issue with how we handle epilogue generation for SLP reductions of reduction paths where the actual live lanes are not "canonical". We need to make sure to identify all live lanes as reductions and thus have to iterate over all participating SLP lanes when walking the reduction SSA use-def chain. Also the previous attempt likely to mitigate such issue in vectorizable_live_operation is misguided and has to be removed. PR tree-optimization/107212 * tree-vect-loop.cc (vectorizable_reduction): Make sure to set STMT_VINFO_REDUC_DEF for all live lanes in a SLP reduction. (vectorizable_live_operation): Do not pun to the SLP node representative for reduction epilogue generation. * gcc.dg/vect/pr107212-1.c: New testcase. * gcc.dg/vect/pr107212-2.c: Likewise. (cherry picked from commit ee467644c53ee2f7d633a8e1f53603feafab4351) Diff: --- gcc/testsuite/gcc.dg/vect/pr107212-1.c | 27 +++++++++++++++++++++++++++ gcc/testsuite/gcc.dg/vect/pr107212-2.c | 23 +++++++++++++++++++++++ gcc/tree-vect-loop.cc | 20 +++++++++++++------- 3 files changed, 63 insertions(+), 7 deletions(-) diff --git a/gcc/testsuite/gcc.dg/vect/pr107212-1.c b/gcc/testsuite/gcc.dg/vect/pr107212-1.c new file mode 100644 index 00000000000..5343f9b6b23 --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/pr107212-1.c @@ -0,0 +1,27 @@ +/* { dg-do run } */ + +#include "tree-vect.h" + +int main() +{ + check_vect (); + + unsigned int tab[6][2] = { {69, 73}, {36, 40}, {24, 16}, + {16, 11}, {4, 5}, {3, 1} }; + + int sum_0 = 0; + int sum_1 = 0; + + for(int t=0; t<6; t++) { + sum_0 += tab[t][0]; + sum_1 += tab[t][1]; + } + + int x1 = (sum_0 < 100); + int x2 = (sum_0 > 200); + + if (x1 || x2 || sum_1 != 146) + __builtin_abort (); + + return 0; +} diff --git a/gcc/testsuite/gcc.dg/vect/pr107212-2.c b/gcc/testsuite/gcc.dg/vect/pr107212-2.c new file mode 100644 index 00000000000..109c2b991a6 --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/pr107212-2.c @@ -0,0 +1,23 @@ +/* { dg-do run } */ + +#include "tree-vect.h" + +int sum_1 = 0; + +int main() +{ + check_vect (); + + unsigned int tab[6][2] = {{150, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0}}; + + int sum_0 = 0; + + for (int t = 0; t < 6; t++) { + sum_0 += tab[t][0]; + sum_1 += tab[t][0]; + } + + if (sum_0 < 100 || sum_0 > 200) + __builtin_abort(); + return 0; +} diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc index 442679836ee..001f7dd8ab3 100644 --- a/gcc/tree-vect-loop.cc +++ b/gcc/tree-vect-loop.cc @@ -6679,10 +6679,20 @@ vectorizable_reduction (loop_vec_info loop_vinfo, } if (!REDUC_GROUP_FIRST_ELEMENT (vdef)) only_slp_reduc_chain = false; - /* ??? For epilogue generation live members of the chain need + /* For epilogue generation live members of the chain need to point back to the PHI via their original stmt for - info_for_reduction to work. */ - if (STMT_VINFO_LIVE_P (vdef)) + info_for_reduction to work. For SLP we need to look at + all lanes here - even though we only will vectorize from + the SLP node with live lane zero the other live lanes also + need to be identified as part of a reduction to be able + to skip code generation for them. */ + if (slp_for_stmt_info) + { + for (auto s : SLP_TREE_SCALAR_STMTS (slp_for_stmt_info)) + if (STMT_VINFO_LIVE_P (s)) + STMT_VINFO_REDUC_DEF (vect_orig_stmt (s)) = phi_info; + } + else if (STMT_VINFO_LIVE_P (vdef)) STMT_VINFO_REDUC_DEF (def) = phi_info; gimple_match_op op; if (!gimple_extract_op (vdef->stmt, &op)) @@ -8755,10 +8765,6 @@ vectorizable_live_operation (vec_info *vinfo, all involved stmts together. */ else if (slp_index != 0) return true; - else - /* For SLP reductions the meta-info is attached to - the representative. */ - stmt_info = SLP_TREE_REPRESENTATIVE (slp_node); } stmt_vec_info reduc_info = info_for_reduction (loop_vinfo, stmt_info); gcc_assert (reduc_info->is_reduc_info);