From patchwork Tue Nov 23 05:51:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xionghu Luo X-Patchwork-Id: 48020 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 6B5813858405 for ; Tue, 23 Nov 2021 05:52:40 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 6B5813858405 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1637646760; bh=TG5B+aA548bYR4u6txbYZHocSq2adrzhnKK6Rf77inI=; h=To:Subject:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:Cc:From; b=adaKdm9lJW0eGY+wS8pe7DGIJEEgRXpxbnAlBRyb0leDn4tauQt2nWHknfpPgPDf8 Ut/5mNOjx6joizfgrrEIxyCAKh/vvJl3eVdYSxmASFxAnoqnMnZapqPYrF/LTuqrg7 3L1A+rq3FA8voAVr9f3AMs4ITnZrA+OBnsRnEixo= X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by sourceware.org (Postfix) with ESMTPS id 311E23858405; Tue, 23 Nov 2021 05:52:11 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 311E23858405 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 1AN5N1WZ003993; Tue, 23 Nov 2021 05:52:09 GMT Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 3cgt3kgbun-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 23 Nov 2021 05:52:09 +0000 Received: from m0098399.ppops.net (m0098399.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 1AN5ptrd028720; Tue, 23 Nov 2021 05:52:09 GMT Received: from ppma04ams.nl.ibm.com (63.31.33a9.ip4.static.sl-reverse.com [169.51.49.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 3cgt3kgbu4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 23 Nov 2021 05:52:09 +0000 Received: from pps.filterd (ppma04ams.nl.ibm.com [127.0.0.1]) by ppma04ams.nl.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 1AN5l62u026984; Tue, 23 Nov 2021 05:52:06 GMT Received: from b06cxnps3075.portsmouth.uk.ibm.com (d06relay10.portsmouth.uk.ibm.com [9.149.109.195]) by ppma04ams.nl.ibm.com with ESMTP id 3cernakyxm-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 23 Nov 2021 05:52:03 +0000 Received: from d06av24.portsmouth.uk.ibm.com (mk.ibm.com [9.149.105.60]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 1AN5pvXm39977234 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 23 Nov 2021 05:51:57 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2D62B42064; Tue, 23 Nov 2021 05:51:57 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A0C284203F; Tue, 23 Nov 2021 05:51:55 +0000 (GMT) Received: from genoa.aus.stglabs.ibm.com (unknown [9.40.192.157]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 23 Nov 2021 05:51:55 +0000 (GMT) To: gcc-patches@gcc.gnu.org Subject: [PATCH] Fix incorrect loop exit edge probability [PR103270] Date: Mon, 22 Nov 2021 23:51:45 -0600 Message-Id: <20211123055145.475825-1-luoxhu@linux.ibm.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: NNrt6QgaSeXKFVrgJ_eBXHejcqISY1vZ X-Proofpoint-ORIG-GUID: IsYcA49DsaXqjypRLrALmeZwXB-P5tIG X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.790,Hydra:6.0.425,FMLib:17.0.607.475 definitions=2021-11-23_01,2021-11-22_02,2020-04-07_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 phishscore=0 bulkscore=0 mlxlogscore=730 suspectscore=0 priorityscore=1501 spamscore=0 adultscore=0 malwarescore=0 clxscore=1011 lowpriorityscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2110150000 definitions=main-2111230027 X-Spam-Status: No, score=-11.2 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Xionghu Luo via Gcc-patches From: Xionghu Luo Reply-To: Xionghu Luo Cc: segher@kernel.crashing.org, Xionghu Luo , hubicka@kam.mff.cuni.cz, wschmidt@linux.ibm.com, linkw@gcc.gnu.org, dje.gcc@gmail.com Errors-To: gcc-patches-bounces+patchwork=sourceware.org@gcc.gnu.org Sender: "Gcc-patches" r12-4526 cancelled jump thread path rotates loop. It exposes a issue in profile-estimate when predict_extra_loop_exits, outer loop's exit edge is marked as inner loop's extra loop exit and set with incorrect prediction, then a hot inner loop will become cold loop finally through optimizations, this patch ignores the EDGE_DFS_BACK edge when searching extra exit edges to avoid unexpected predict_edge. gcc/ChangeLog: PR middle-end/103270 * predict.c (predict_extra_loop_exits): Ignore EDGE_DFS_BACK edge. gcc/ChangeLog: PR middle-end/103270 * predict.c (predict_extra_loop_exits): New. --- gcc/predict.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/gcc/predict.c b/gcc/predict.c index 68b11135680..1ae8ccff72c 100644 --- a/gcc/predict.c +++ b/gcc/predict.c @@ -1910,6 +1910,10 @@ predict_extra_loop_exits (edge exit_edge) continue; if ((check_value_one ^ integer_onep (val)) == 1) continue; +#if 0 + if (e->flags & EDGE_DFS_BACK) + continue; +#endif if (EDGE_COUNT (e->src->succs) != 1) { predict_paths_leading_to_edge (e, PRED_LOOP_EXTRA_EXIT, NOT_TAKEN);