From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by sourceware.org (Postfix) with ESMTPS id 63A303858D32 for ; Mon, 29 Aug 2022 06:35:22 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 63A303858D32 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=linux.ibm.com Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 27T6KcDu026821; Mon, 29 Aug 2022 06:35:17 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=message-id : date : mime-version : subject : to : cc : references : from : in-reply-to : content-type : content-transfer-encoding; s=pp1; bh=qiExbLed7m1Tw5lbLF9ux7QTcdD9xcaAGjWJ1Bj1haU=; b=Upg8N22VdlARkv3sbpCIAZpoplK/kzRH8FI+Dk68VOB4vi/2UNJGa13vrh/gb2k+DvLI qft+82/qW6UJvgndjyQgPh+TtqMJVWYHBNaQ9dqIUm2jrQeJuznhVRaCqw98GDiUa0tB br/buT3MjgQYjVPUX380+FaDyqn4eXfl8FoDje4ei7lAurwxxeTWCOPiEqj+dkby0m+1 +1ZKf6VNLkqonsFAWaQ5ARpsk556heh7ryFqXHovYRMccOtKsxue4BvsmrK3gqpN15xe RdtyqZ8TqYX5tE6jvH43h9WxRL2NjXLxB5gdv10a2oIIz3igxxMi/z2/g2zP89NxaaG9 Xw== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3j8r3v0acb-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 29 Aug 2022 06:35:17 +0000 Received: from m0098410.ppops.net (m0098410.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 27T6NJL2000779; Mon, 29 Aug 2022 06:35:16 GMT Received: from ppma06ams.nl.ibm.com (66.31.33a9.ip4.static.sl-reverse.com [169.51.49.102]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3j8r3v0aac-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 29 Aug 2022 06:35:16 +0000 Received: from pps.filterd (ppma06ams.nl.ibm.com [127.0.0.1]) by ppma06ams.nl.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 27T6LQb2019509; Mon, 29 Aug 2022 06:35:13 GMT Received: from b06cxnps4076.portsmouth.uk.ibm.com (d06relay13.portsmouth.uk.ibm.com [9.149.109.198]) by ppma06ams.nl.ibm.com with ESMTP id 3j7ahj1x0s-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 29 Aug 2022 06:35:13 +0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 27T6ZBk133292788 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 29 Aug 2022 06:35:11 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E4DBB4C04A; Mon, 29 Aug 2022 06:35:10 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CA2DB4C044; Mon, 29 Aug 2022 06:35:08 +0000 (GMT) Received: from [9.197.231.116] (unknown [9.197.231.116]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 29 Aug 2022 06:35:08 +0000 (GMT) Message-ID: <5404908f-76d9-8898-3621-1f54064892fb@linux.ibm.com> Date: Mon, 29 Aug 2022 14:35:07 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [PATCH] predict: Adjust optimize_function_for_size_p [PR105818] Content-Language: en-US To: Jan Hubicka Cc: Richard Sandiford , GCC Patches , Segher Boessenkool , Jan Hubicka , Richard Biener References: <23b4998b-bbe6-b052-d7f5-5304ee0f46a3@linux.ibm.com> <77f90ce9-8c36-e442-03b6-82d5450da2a1@linux.ibm.com> <0122f231-450a-1280-ba23-fb7127412aa9@linux.ibm.com> From: "Kewen.Lin" In-Reply-To: <0122f231-450a-1280-ba23-fb7127412aa9@linux.ibm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: 2OLTzGl2Imd1_DEVBXy6dGXVoMMbqCmB X-Proofpoint-ORIG-GUID: e-BWAghmXih6S6LDwz-06O1Mbbm5Fu6x X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-08-29_03,2022-08-25_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 lowpriorityscore=0 clxscore=1011 mlxscore=0 impostorscore=0 malwarescore=0 mlxlogscore=999 suspectscore=0 phishscore=0 priorityscore=1501 spamscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2207270000 definitions=main-2208290031 X-Spam-Status: No, score=-11.9 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_EF,GIT_PATCH_0,KAM_SHORT,NICE_REPLY_A,RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_PASS,TXREP,T_SCC_BODY_TEXT_LINE 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: on 2022/8/15 16:33, Kewen.Lin via Gcc-patches wrote: > on 2022/7/11 11:42, Kewen.Lin wrote: >> on 2022/6/15 14:20, Kewen.Lin wrote: >>> Hi Honza, >>> >>> Thanks for the comments! Some replies are inlined below. >>> >>> on 2022/6/14 19:37, Jan Hubicka wrote: >>>>> Hi, >>>>> >>>>> Function optimize_function_for_size_p returns OPTIMIZE_SIZE_NO >>>>> if func->decl is not null but no cgraph node is available for it. >>>>> As PR105818 shows, this could give unexpected result. For the >>>>> case in PR105818, when parsing bar decl in function foo, the cfun >>>>> is a function structure for foo, for which there is none cgraph >>>>> node, so it returns OPTIMIZE_SIZE_NO. But it's incorrect since >>>>> the context is to optimize for size, the flag optimize_size is >>>>> true. >>>>> >>>>> The patch is to make optimize_function_for_size_p to check >>>>> optimize_size as what it does when func->decl is unavailable. >>>>> >>>>> One regression failure got exposed on aarch64-linux-gnu: >>>>> >>>>> PASS->FAIL: gcc.dg/guality/pr54693-2.c -Os \ >>>>> -DPREVENT_OPTIMIZATION line 21 x == 10 - i >>>>> >>>>> The difference comes from the macro LOGICAL_OP_NON_SHORT_CIRCUIT >>>>> used in function fold_range_test during c parsing, it uses >>>>> optimize_function_for_speed_p which is equal to the invertion >>>>> of optimize_function_for_size_p. At that time cfun->decl is valid >>>>> but no cgraph node for it, w/o this patch function >>>>> optimize_function_for_speed_p returns true eventually, while it >>>>> returns false with this patch. Since the command line option -Os >>>>> is specified, there is no reason to interpret it as "for speed". >>>>> I think this failure is expected and adjust the test case >>>>> accordingly. >>>>> >>>>> Is it ok for trunk? >>>>> >>>>> BR, >>>>> Kewen >>>>> ----- >>>>> >>>>> PR target/105818 >>>>> >>>>> gcc/ChangeLog: >>>>> >>>>> * predict.cc (optimize_function_for_size_p): Check optimize_size when >>>>> func->decl is valid but its cgraph node is unavailable. >>>>> >>>>> gcc/testsuite/ChangeLog: >>>>> >>>>> * gcc.target/powerpc/pr105818.c: New test. >>>>> * gcc.dg/guality/pr54693-2.c: Adjust for aarch64. >>>>> --- >>>>> gcc/predict.cc | 2 +- >>>>> gcc/testsuite/gcc.dg/guality/pr54693-2.c | 2 +- >>>>> gcc/testsuite/gcc.target/powerpc/pr105818.c | 9 +++++++++ >>>>> 3 files changed, 11 insertions(+), 2 deletions(-) >>>>> create mode 100644 gcc/testsuite/gcc.target/powerpc/pr105818.c >>>>> >>>>> diff --git a/gcc/predict.cc b/gcc/predict.cc >>>>> index 5734e4c8516..6c60a973236 100644 >>>>> --- a/gcc/predict.cc >>>>> +++ b/gcc/predict.cc >>>>> @@ -268,7 +268,7 @@ optimize_function_for_size_p (struct function *fun) >>>>> cgraph_node *n = cgraph_node::get (fun->decl); >>>>> if (n) >>>>> return n->optimize_for_size_p (); >>>>> - return OPTIMIZE_SIZE_NO; >>>>> + return optimize_size ? OPTIMIZE_SIZE_MAX : OPTIMIZE_SIZE_NO; >>>> >>>> We could also do (opt_for_fn (cfun->decl, optimize_size) that is >>>> probably better since one can change optimize_size with optimization >>>> attribute. >>> >>> Good point, agree! >>> >>>> However I think in most cases we check for optimize_size early I think >>>> we are doing something wrong, since at that time htere is no profile >>>> available. Why exactly PR105818 hits the flag change issue? >>> >>> For PR105818, the reason why the flag changs is that: >>> >>> Firstly, the inconsistent flag is OPTION_MASK_SAVE_TOC_INDIRECT bit >>> of rs6000_isa_flags_explicit, it's set as below: >>> >>> /* If we can shrink-wrap the TOC register save separately, then use >>> -msave-toc-indirect unless explicitly disabled. */ >>> if ((rs6000_isa_flags_explicit & OPTION_MASK_SAVE_TOC_INDIRECT) == 0 >>> && flag_shrink_wrap_separate >>> && optimize_function_for_speed_p (cfun)) >>> rs6000_isa_flags |= OPTION_MASK_SAVE_TOC_INDIRECT; >>> >>> Initially, rs6000 initialize target_option_default_node with >>> OPTION_MASK_SAVE_TOC_INDIRECT unset, at that time cfun is NULL >>> and optimize_size is true. >>> >>> Later, when c parser handling function foo, it builds target >>> option node as target_option_default_node in function >>> handle_optimize_attribute, it does global option saving and >>> verifying there as well, at that time the cfun is NULL, no >>> issue is found. And function store_parm_decls allocates >>> struct_function for foo then, cfun becomes function struct >>> for foo, when c parser continues to handle the decl bar in >>> foo, function handle_optimize_attribute works as before, >>> tries to restore the target options at the end, it calls >>> targetm.target_option.restore (rs6000_function_specific_restore) >>> which calls function rs6000_option_override_internal again, >>> at this time the cfun is not NULL while there is no cgraph >>> node for its decl, optimize_function_for_speed_p returns true >>> and gets the OPTION_MASK_SAVE_TOC_INDIRECT bit of flag >>> rs6000_isa_flags set unexpectedly. It becomes inconsistent >>> as the one saved previously. >>> >>> IMHO, both contexts of global and function decl foo here hold >>> optimize_size, function optimize_function_for_speed_p should >>> not return true anyway. >>> >>> btw, the aarch64 failed case also gets the unexpected >>> result for optimize_function_for_speed_p during c parsing >>> (fold_range_test <- ... <- c_parser_condition). >>> >>> IIUC, in parsing time we don't have the profile information >>> available. >>> >> >> Hi Honza, >> >> Does the above explanation sound reasonable to you? >> > Hi Honza, Gentle ping again ... BR, Kewen