From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by sourceware.org (Postfix) with ESMTP id 204F03858CDA for ; Tue, 10 Jan 2023 10:42:09 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 204F03858CDA Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 9A46C4B3; Tue, 10 Jan 2023 02:42:50 -0800 (PST) Received: from localhost (e121540-lin.manchester.arm.com [10.32.99.50]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 26D263F587; Tue, 10 Jan 2023 02:42:08 -0800 (PST) From: Richard Sandiford To: Richard Biener Mail-Followup-To: Richard Biener ,gcc-patches@gcc.gnu.org, richard.sandiford@arm.com Cc: gcc-patches@gcc.gnu.org Subject: Re: [PATCH] tree-optimization/108314 - avoid BIT_NOT optimization for extract-last References: <20230110094614.0E81A1358A@imap2.suse-dmz.suse.de> Date: Tue, 10 Jan 2023 10:42:06 +0000 In-Reply-To: <20230110094614.0E81A1358A@imap2.suse-dmz.suse.de> (Richard Biener's message of "Tue, 10 Jan 2023 10:46:13 +0100 (CET)") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Spam-Status: No, score=-38.1 required=5.0 tests=BAYES_00,GIT_PATCH_0,KAM_DMARC_NONE,KAM_DMARC_STATUS,KAM_LAZY_DOMAIN_SECURITY,SPF_HELO_NONE,SPF_NONE,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: Richard Biener writes: > The extract-last reduction internal function expects the then and > else clause as vector and scalar and thus we cannot perform optimization > of the inversion of the condition by swapping the then/else clauses. > > Bootstrap and regtest running on x86_64-unknown-linux-gnu, OK? Sorry for not having found the time to look at the PR yet. Like you say in the trail, it seems kind-of familiar. I think we should instead prevent the else in: scalar_cond_masked_key cond (cond_expr, ncopies); if (loop_vinfo->scalar_cond_masked_set.contains (cond)) masks = &LOOP_VINFO_MASKS (loop_vinfo); else { for EXTRACT_LAST. We've lost as soon as swap_cond_operands gets set to true. Thanks, Richard > Thanks, > Richard. > > PR tree-optimization/108314 > * tree-vect-stmts.cc (vectorizable_condition): Do not > perform BIT_NOT_EXPR optimization for EXTRACT_LAST_REDUCTION. > > * gcc.dg/vect/pr108314.c: New testcase. > --- > gcc/testsuite/gcc.dg/vect/pr108314.c | 16 ++++++++++++++++ > gcc/tree-vect-stmts.cc | 13 +++++++++---- > 2 files changed, 25 insertions(+), 4 deletions(-) > create mode 100644 gcc/testsuite/gcc.dg/vect/pr108314.c > > diff --git a/gcc/testsuite/gcc.dg/vect/pr108314.c b/gcc/testsuite/gcc.dg/vect/pr108314.c > new file mode 100644 > index 00000000000..07260e06915 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/vect/pr108314.c > @@ -0,0 +1,16 @@ > +/* { dg-do compile } */ > +/* { dg-additional-options "-march=armv9-a" { target aarch64-*-* } } */ > + > +int x, y, z; > + > +void f(void) > +{ > + int t = 4; > + for (; x; x++) > + { > + if (y) > + continue; > + t = 0; > + } > + z = t; > +} > diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc > index 6ddd41fb473..eb4ca1f184e 100644 > --- a/gcc/tree-vect-stmts.cc > +++ b/gcc/tree-vect-stmts.cc > @@ -10677,7 +10677,8 @@ vectorizable_condition (vec_info *vinfo, > vect_finish_stmt_generation (vinfo, stmt_info, new_stmt, gsi); > if (bitop2 == NOP_EXPR) > vec_compare = new_temp; > - else if (bitop2 == BIT_NOT_EXPR) > + else if (bitop2 == BIT_NOT_EXPR > + && reduction_type != EXTRACT_LAST_REDUCTION) > { > /* Instead of doing ~x ? y : z do x ? z : y. */ > vec_compare = new_temp; > @@ -10686,9 +10687,13 @@ vectorizable_condition (vec_info *vinfo, > else > { > vec_compare = make_ssa_name (vec_cmp_type); > - new_stmt > - = gimple_build_assign (vec_compare, bitop2, > - vec_cond_lhs, new_temp); > + if (bitop2 == BIT_NOT_EXPR) > + new_stmt > + = gimple_build_assign (vec_compare, bitop2, new_temp); > + else > + new_stmt > + = gimple_build_assign (vec_compare, bitop2, > + vec_cond_lhs, new_temp); > vect_finish_stmt_generation (vinfo, stmt_info, > new_stmt, gsi); > }