From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by sourceware.org (Postfix) with ESMTPS id 604E93858C50 for ; Tue, 2 Aug 2022 16:05:43 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 604E93858C50 Received: from pps.filterd (m0246629.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 272G1wiU025451 for ; Tue, 2 Aug 2022 16:05:42 GMT Received: from iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta01.appoci.oracle.com [130.35.100.223]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3hmvh9q4q7-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Tue, 02 Aug 2022 16:05:42 +0000 Received: from pps.filterd (iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (8.17.1.5/8.17.1.5) with ESMTP id 272EwkLZ014118 for ; Tue, 2 Aug 2022 16:05:40 GMT Received: from nam02-bn1-obe.outbound.protection.outlook.com (mail-bn1nam07lp2043.outbound.protection.outlook.com [104.47.51.43]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 3hmu32fmrj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Tue, 02 Aug 2022 16:05:40 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Bi4JPodFSIvucTYBmALiQl5Kk3T3yoZR4zpuY/FBFL/AD/SuTIk8LIMIbExwsxduQjjRLRVBix3rr1bfxWvs3dQM/wvTRYEKsbXUg0DYCqH1kk0MWqBWKuNxeYep/1U9oly4GkAWWRXwAaItx+gQt8xBCpdK78vHqIkG07NRx/kTPNjbW9yLtJ5wSt0gmLwPobE2ucVFb6OWy5K/Rn0lmJuqQ5NSoFo+9pHu94W8WOc2ocaLscYoiev0zrgWNfKUM0taSwehiD4YhBEGinaG0OmHUojuxJvx7BOIrJfk8qeVCyIkIpw0OACBYullbMfuKbXJmDx0/rinalH189GR5w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=OUkVbA9Yz+Qtg+aDQ6dcPuSG35Xmb9lNeXMaCTYiT90=; b=CA3e31Gg8VZL0r91/FwEXpzIzhijl4hRlse7JHUV+L5OyfZLL9fRpEv2BO7X8q6El3B+wuBAF1YMTxtG2cHBqtuLN8/8WFs7ldf6pcAv0R+FKfvuNO04iHIRVMWl78aTbcqy5Kn98HOJu8RdCl26MjfMiCVfqps8qbo69ncf7ipmbFbNIYx5CGgh5gmW8lDXQljuDW3y5maLqjbCljk0d63uWP3ULhk+XYK5SrpUY1dZAxsgByPIpFBi3D+jBW0mAL19M/3ZzYEb3VWFQ9ge6uquxJOUSgXP+VRu3QPXJg0cXRN+X89IPJRe4xzVla9OZ+U9NI0240f6G9dv+KmB+A== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=oracle.com; dmarc=pass action=none header.from=oracle.com; dkim=pass header.d=oracle.com; arc=none Received: from MN2PR10MB3213.namprd10.prod.outlook.com (2603:10b6:208:131::33) by BYAPR10MB2421.namprd10.prod.outlook.com (2603:10b6:a02:b3::19) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5482.12; Tue, 2 Aug 2022 16:05:38 +0000 Received: from MN2PR10MB3213.namprd10.prod.outlook.com ([fe80::815f:640c:8792:186b]) by MN2PR10MB3213.namprd10.prod.outlook.com ([fe80::815f:640c:8792:186b%5]) with mapi id 15.20.5482.016; Tue, 2 Aug 2022 16:05:38 +0000 Message-ID: Date: Tue, 2 Aug 2022 09:05:35 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH] btf: do not use the CHAR `encoding' bit for BTF Content-Language: en-US To: "Jose E. Marchesi" Cc: Indu Bhagat , gcc-patches@gcc.gnu.org References: <877d458k7r.fsf@oracle.com> <3c4bc777-c472-d5a1-74f2-1a99b951e9db@oracle.com> <878ro6bqip.fsf@oracle.com> From: David Faust In-Reply-To: <878ro6bqip.fsf@oracle.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: BY5PR16CA0016.namprd16.prod.outlook.com (2603:10b6:a03:1a0::29) To MN2PR10MB3213.namprd10.prod.outlook.com (2603:10b6:208:131::33) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 30d6f406-0bb4-46ad-2580-08da74a0d758 X-MS-TrafficTypeDiagnostic: BYAPR10MB2421:EE_ X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: PVW/sEqwp3tETFRxrl1Bxnqf+C0pWRW8kJncjp6oqcaVhJYVwquBnH5EF6HViHO12gVOlJZamyqTWAR1N65km2D21vsd8dGWcf6CCgbKnz/WpnvWVTtUXf8AjVl97C7Cy8DCyhELQMfK1/HrlHwL5tU+itZC2ic1VMw/eN67hB4au8VVgCU4/kCE2L6alg1Ht4FAJMNTdBiToRLOPcXZL9serErXkWtMKRThl5yedALSjz6sbh9KUKhcj98+8CYsUdzvQCDV89lgkQo0p7Uz4J6wMtgBxv5tIx1OjcBBHQmwoD6LstHnGnniZkbWDNFJOmpImaX3r0XB91+kchO8+rvGMlaBpeLjFDiCRZrSrtH+l3zn18nASHyj18ivXpFjWeA/Bw375rSOUKE9k99EBfhByq1t74hHJq+Ta8SnmsgXab4iiTIbdnto9wzmctK6lC3aCF2qXrQTnOx7hdMCYufdVyXsKZ6iCEfX8Inn7zWD+oODY+V3Xi+iB1hpobMaAC1h29tIpVK0uwMIeryq/wzWwYBukXFfrsgX73cNrKdSk84XZd2naUXQMX19EppKNNP0jow22So9B2aMDxSjDJGfbjt+HtWN6rMCdTV4SvZQ331S04CjDyFjvJ9UDby8tkF6worjMFDgM/4AZW5iIHiLhOuPzTdzVhb9s06ylueLGiak8zH/LDck5PrSp0HyZCs2ZMhkqF+FnD3zjG4Hizp8YQ4kX422ZlI2j0lKp81Pd5xV7FG9hMMVQ+Mhq928vR5Sb4AYsrkwLMNaMeTck3pcrcY0vcJIixTDKvQXMsbkXXVGMFWDznRr7RqpOD22VV9/iuAusF/w0WxZ2iZVGoJRKXnph7JzyEf/8PYz40E= X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:MN2PR10MB3213.namprd10.prod.outlook.com; PTR:; CAT:NONE; SFS:(13230016)(39860400002)(136003)(396003)(366004)(346002)(376002)(2616005)(53546011)(186003)(36756003)(6512007)(6666004)(31686004)(2906002)(6506007)(41300700001)(478600001)(44832011)(38100700002)(86362001)(5660300002)(31696002)(316002)(6486002)(6862004)(6636002)(37006003)(8676002)(4326008)(66476007)(66556008)(66946007)(8936002)(81973001)(45980500001)(43740500002); DIR:OUT; SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?cFRRNnIxNWV1VENWL1pjV3p6d2x1RlhabS8zL2NRNmdJRVBMV3h3dUJIK2NP?= =?utf-8?B?dG94RUc1U25pRXJaaTJ5d1N3VGtOY0NZSVdWTnRVcnFLcVpMcC95UGxqMlJP?= =?utf-8?B?Tm1hd1lxbjJ3NWJlR3l5aERDcy81RzNQSXRXSDRRamR4Z0J2eU9VQ1RwTkRt?= =?utf-8?B?TktTZFdZN3cwVitOK3hVSXJKT0M0dVlBYm13dmwxcllqa1B2eW83WU5EUGNC?= =?utf-8?B?MzN4Y0xjR1FOemZQQ3p2TXVPRTdiUW81S0VWRlVFaTBSVzZVdERyUnF5UWhX?= =?utf-8?B?am5LSmdnblBaNWF4allWRU9QQTZaYlBsanZ3ODBtQlJVaHFRUDh3bURveWRZ?= =?utf-8?B?Z2F6R3pxcmRZR05xNmRpalRiZUZ1OTBBRit4WFJNakp2MHNYaERKQmRNNHFk?= =?utf-8?B?ejI4cy9yby8yU0FsWjlCay9yc1RESmthVDJKL1VzbDlGSE10clBNRENnQ3Rs?= =?utf-8?B?bVJzNXJ5bUJqTGk2Q01VOHZIdE93T1U0VUJUWnEyamliaVIvdHhDWUdQWmlC?= =?utf-8?B?QmpmeTRBWjJKOEFraTFGRXY0OFhkbytHSWJpMkRxMjd2bnNwOHpHWExZSzRz?= =?utf-8?B?SjVWV0RleTJlNHgwZ1dsOFVVTmFIMHpkN2hsUXpUNWttZGtkTEw3MktISXln?= =?utf-8?B?a3dpNnlRUGhHbit1U2E0Z1RFUi9GRjk5VTFreCsrbVJ3L1FaaGRiZXhLVFVU?= =?utf-8?B?TkFYVmQ4aUh5MWZvTXgweGxZKzRoR3NXa2RFMC8yK2FCY29melNGYlJQM3lY?= =?utf-8?B?YitzZS94cFNXNlR3U214Q21SZzJmTlVlcmJORVdhM0E0ZWczY0JST09CeG90?= =?utf-8?B?WlNBYWdxWFZVVlN5TE5XRVpjQ2NKSEMzazA0bUEwRWUvWlNSY1BlOGprNGZY?= =?utf-8?B?OHdMSXVyYzkzMXNqS3lFNGsxaFhRV1hhTnpMV3NEQnNNVFhGQVdDdW9UMUcz?= =?utf-8?B?T3Q0NnZqZnNWZEpEdVpXVTlyWXA3V3JEZXlMZ1BkRmpVZWdlRUNUQWVydjZH?= =?utf-8?B?SklHNUkvSHlsRU4zd0EyaWQ0dlFjODlTVFA1R1c3WWp3eHl4c3RzS3dUWkNl?= =?utf-8?B?RjZNRGF2QmtBQUcwdjhpZ0dXcVRVcU92aTNsK3ZTalVXT2lXNWJPcTFOVE1q?= =?utf-8?B?S3U3bXJIU3ZVV2Jld2g0elhBRFplSXIrZWgybGhhaGNIRGR2cy9sbUpBNFdp?= =?utf-8?B?ak1pL0E1NTNzT1F0YUtQaEgvNDJMWHJaeUNxT3QrQmQwdmlWSi8xVWJ5VXY1?= =?utf-8?B?UFRtK01ydEU3YnBBampGOG50dk1tZ2VMK3I0c2tEdUZwWTYwOGQ3MExaT0F1?= =?utf-8?B?ckpGTDEzbVRyRnVMODVxR2lJWk5Ed1dINU9iM241NGlURXJtaDBOR2M0NkVL?= =?utf-8?B?US9jTVhWUjdsTmZRWDZrQ0lTS3Q1TTgxWnVGOCtGZk8vTE0rUVpjMUJ4M2J2?= =?utf-8?B?V045QUtCa3VKbHdMNzh2MTBXdlg4VEhTVXgvTmVUeXd5ZzRPQVdGa2pEY2lt?= =?utf-8?B?RVZVMnkwRXFrSGhjbTZQczk1SkNwZWhubHF2NmxqeTAvNVlDeENDM0FDNjUv?= =?utf-8?B?eDhUeUpIOVdnbmFmR0RyRnFZRkNUYWJua2dJSmJoVFFycEt2R3p0YlA4a09S?= =?utf-8?B?NW5XRjAxY3E5NG5naHcwWXphOVlHUTcwbEJ1bTFTbzBuaEl4ZWFSdlhxV082?= =?utf-8?B?SFlMTGVFV2dHQ0ZUTmRjc2NlaHZLMFNBa1pkQ2NIQmZkT2tGUnhpd1VnNzE2?= =?utf-8?B?SWt4ZzJiQnZITnJFOEtKNzJLc0hGZWkxdFpvb1NWc0NHODhWeVJ5UExxb09E?= =?utf-8?B?akxKaDBJTnRWTWw4eEdEQjdUQ0ovM1BTTlRwdHByQVhnMzZicjAxZTdCSk5p?= =?utf-8?B?SDJtd0NYUDVnK2syZlAwcnljWERDN0s0Z2dBRFkrTzlOL1hVc0pTVk1GNzc5?= =?utf-8?B?Z05qdG5jRktYS2h0Z3J6M1d3NEZuak9NeWtFZzM2UFVjbmlpSmorVkhDR1JZ?= =?utf-8?B?ejk4QTRDQjNlVVBOcjlUdUtYYW5YUXhBZFVIVWVYYWtWMzZQOXdOU1RSOEZy?= =?utf-8?B?TU5mRkt1QjFmUm9LYTlJTjZHNjRpZWcrTk9pcW8ySGNFSS9qMTEvc0NmbVhP?= =?utf-8?B?WHBNRXJuRElIamVNVWdWQjlqSmxTc01rbFhSQnN1czl5SlFLTVIzQzR5SDJH?= =?utf-8?Q?pRQ6+2W2E3gmlmM3X1aUEeI=3D?= X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: 30d6f406-0bb4-46ad-2580-08da74a0d758 X-MS-Exchange-CrossTenant-AuthSource: MN2PR10MB3213.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Aug 2022 16:05:38.4688 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: /HpRLXq/9V0SVTjl8/V9mDRO+op4ZO9Cv+ADSAiVr1LUN8/SQm0MGsm6T/xUVHUKhEtzuJZHuHn8MaI7/FTt1Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR10MB2421 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.883,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-08-02_11,2022-08-02_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 mlxlogscore=895 phishscore=0 malwarescore=0 suspectscore=0 spamscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2206140000 definitions=main-2208020075 X-Proofpoint-ORIG-GUID: bKbCzEFpioWIMxspTHWnkEurWzQIy55c X-Proofpoint-GUID: bKbCzEFpioWIMxspTHWnkEurWzQIy55c X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, NICE_REPLY_A, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H2, 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 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-List-Received-Date: Tue, 02 Aug 2022 16:05:46 -0000 On 8/2/22 08:42, Jose E. Marchesi wrote: > >> On 7/26/22 14:58, Indu Bhagat wrote: >>> On 7/22/22 4:23 AM, Jose E. Marchesi via Gcc-patches wrote: >>>> >>>> Contrary to CTF and our previous expectations, as per [1], turns out >>>> that in BTF: >>>> >>>> 1) The `encoding' field in integer types shall not be treated as a >>>> bitmap, but as an enumerated, i.e. these bits are exclusive to each >>>> other. >>>> >>>> 2) The CHAR bit in `encoding' shall _not_ be set when emitting types >>>> for char nor `unsigned char'. >>>> >>> >>> Hmm...well. At this time, I suggest we make a note of this in the btf.h >>> for posterity that BTF_INT_CHAR is to not be used (i.e., BTF_INT_CHAR >>> should not be set for char / unsigned char). >> >> Agreed it would be good to add this note. > > Hmm, I am not sure such a comment actually belongs to include/btf.h, > which is not specific to the compiler and is supposed to reflect the BTF > format per-se. The CHAR bit is documented in the kernel documentation > and it may be used at some point by bpflib, or who knows what. OK you make a good point. In that case the patch LGTM to commit. Thanks! > > That's why I put the comment in btfout.cc instead, to make it clear that > BTF_INT_CHAR is indeed not to be set for char / unsigned char by the > compiler: > >>>> + /* In BTF the CHAR `encoding' seems to not be used, so clear it >>>> + here. */ >>>> + dtd->dtd_u.dtu_enc.cte_format &= ~BTF_INT_CHAR;