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 61C12385841A for ; Wed, 7 Sep 2022 14:20:41 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 61C12385841A 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 (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 287Dv4Nc005467 for ; Wed, 7 Sep 2022 14:20:40 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : subject : date : message-id : mime-version : content-transfer-encoding; s=pp1; bh=vnCJjlltPP+CDgY/i/dTmGCBnm5u8EuTMyVhru1NJ3Q=; b=l+/C4e3q+941ueN06vdbQ4J/92ITJH/Z/yVzVFYVeu9P1ZGQJjOw59x8/r3YIFafg6el VbK3tcIux8O5r6u2hXeEFclG6+uqz3yku3+5TxvQ3RrkYgITRSX6TESD2tFNNw+NS+3o jOlpqipiaAWY5f9nCo4vMCy7YyhXMM4Om3ny5g67TgD7r15nrGMBsdt8ZjOnXyCoVkXy lnDPHGog5RlOFA5xouvbjkIUyX3cpFtgS7EAltMg2bSf9BbTa2OuZXzy6Snd99L4F+wH I4STqyEnE5e7QuxqtEZz16RELOHhpPGzFAoGa3vRXRzKhsAB76t3xQ2xHsxIOPj6YOx+ dg== Received: from ppma04ams.nl.ibm.com (63.31.33a9.ip4.static.sl-reverse.com [169.51.49.99]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3jevmugyhp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 07 Sep 2022 14:20:40 +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 287E68VG021498 for ; Wed, 7 Sep 2022 14:20:37 GMT Received: from b06avi18878370.portsmouth.uk.ibm.com (b06avi18878370.portsmouth.uk.ibm.com [9.149.26.194]) by ppma04ams.nl.ibm.com with ESMTP id 3jbxj8w9vc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 07 Sep 2022 14:20:37 +0000 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06avi18878370.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 287EKx4E42271158 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Wed, 7 Sep 2022 14:20:59 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6AECBA4051 for ; Wed, 7 Sep 2022 14:20:35 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4D14FA4053 for ; Wed, 7 Sep 2022 14:20:35 +0000 (GMT) Received: from t8345026.lnxne.boe (unknown [9.152.108.100]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTPS for ; Wed, 7 Sep 2022 14:20:35 +0000 (GMT) From: Stefan Schulze Frielinghaus To: gcc-patches@gcc.gnu.org Subject: [PATCH 0/2] Variable tracking and subvalues Date: Wed, 7 Sep 2022 16:20:24 +0200 Message-Id: <20220907142026.936922-1-stefansf@linux.ibm.com> X-Mailer: git-send-email 2.37.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: KjVtKn7WGetpaavveiG30wIMh6GKB3eF X-Proofpoint-ORIG-GUID: KjVtKn7WGetpaavveiG30wIMh6GKB3eF X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.528,FMLib:17.11.122.1 definitions=2022-09-07_07,2022-09-07_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 impostorscore=0 priorityscore=1501 bulkscore=0 clxscore=1015 suspectscore=0 mlxlogscore=585 lowpriorityscore=0 mlxscore=0 adultscore=0 phishscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2207270000 definitions=main-2209070055 X-Spam-Status: No, score=-2.4 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_EF,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: For variable tracking there exists cases where a value is moved in a wider mode than its native mode. For example: int foo (int x) { bar (x); return x; } compiles on IBM zSystems into 0x00000000010012b0 <+0>: stmg %r12,%r15,96(%r15) 0x00000000010012b6 <+6>: lgr %r12,%r2 0x00000000010012ba <+10>: lay %r15,-160(%r15) 0x00000000010012c0 <+16>: brasl %r14,0x10012a0 0x00000000010012c6 <+22>: lgr %r2,%r12 0x00000000010012ca <+26>: lmg %r12,%r15,256(%r15) 0x00000000010012d0 <+32>: br %r14 Initially variable x with SImode is held in register r2 which is moved to call-saved register r12 with DImode from where it is also restored. The cselib patch records that the initial value held in r2 is a subvalue of r12 which enables var-tracking to emit a register location entry: (gdb) info address x Symbol "x" is multi-location: Base address 0x10012b0 Range 0x10012b0-0x10012c5: a variable in $r2 Range 0x10012c5-0x10012d0: a variable in $r12 Range 0x10012d0-0x10012d2: a variable in $r2 However, this only works for straight-line programs and fails e.g. for __attribute__((noinline, noclone)) void fn1 (int x) { __asm volatile ("" : "+r" (x) : : "memory"); } __attribute__((noinline, noclone)) int fn2 (int x, int y) { if (x) { fn1 (x); // (*) fn1 (x); } return y; } __attribute__((noinline, noclone)) int fn3 (int x, int y) { return fn2 (x, y); } int main () { fn3 (36, 25); return 0; } At (*) variable x is moved into a call-saved register. However, the former cselib patch does not cover this since cselib flushes its tables across jumps. In order to not give up entirely by the second patch an entry value is referred. In summary this fixes the following guality tests for IBM zSystems: Fixed by cselib patch: FAIL: gcc.dg/guality/pr43051-1.c -O1 -DPREVENT_OPTIMIZATION line 35 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects -DPREVENT_OPTIMIZATION line 35 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects -DPREVENT_OPTIMIZATION line 40 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -O3 -fomit-frame-pointer -funroll-loops -fpeel-loops -ftracer -finline-functions -DPREVENT_OPTIMIZATION line 35 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -O2 -DPREVENT_OPTIMIZATION line 40 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -O2 -flto -fno-use-linker-plugin -flto-partition=none -DPREVENT_OPTIMIZATION line 40 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -O3 -g -DPREVENT_OPTIMIZATION line 35 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -O3 -g -DPREVENT_OPTIMIZATION line 40 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -O2 -DPREVENT_OPTIMIZATION line 35 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -O2 -flto -fno-use-linker-plugin -flto-partition=none -DPREVENT_OPTIMIZATION line 35 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -O3 -fomit-frame-pointer -funroll-loops -fpeel-loops -ftracer -finline-functions -DPREVENT_OPTIMIZATION line 40 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -Og -DPREVENT_OPTIMIZATION line 35 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -Og -DPREVENT_OPTIMIZATION line 40 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -O1 -DPREVENT_OPTIMIZATION line 40 v == 1 Fixed by var-tracking patch: FAIL: gcc.dg/guality/pr54519-1.c -O2 -DPREVENT_OPTIMIZATION line 23 x == 98 FAIL: gcc.dg/guality/pr54519-5.c -Og -DPREVENT_OPTIMIZATION line 17 y == 25 FAIL: gcc.dg/guality/pr54519-1.c -O2 -flto -fno-use-linker-plugin -flto-partition=none -DPREVENT_OPTIMIZATION line 20 x == 36 FAIL: gcc.dg/guality/pr54519-1.c -Og -DPREVENT_OPTIMIZATION line 20 x == 36 FAIL: gcc.dg/guality/pr54519-1.c -O2 -flto -fno-use-linker-plugin -flto-partition=none -DPREVENT_OPTIMIZATION line 23 x == 98 FAIL: gcc.dg/guality/pr54551.c -O2 -flto -fno-use-linker-plugin -flto-partition=none -DPREVENT_OPTIMIZATION line 18 a == 4 FAIL: gcc.dg/guality/pr54551.c -O3 -g -DPREVENT_OPTIMIZATION line 18 a == 4 FAIL: gcc.dg/guality/pr54519-1.c -O1 -DPREVENT_OPTIMIZATION line 23 x == 98 FAIL: gcc.dg/guality/pr54551.c -Os -DPREVENT_OPTIMIZATION line 18 a == 4 FAIL: gcc.dg/guality/pr54519-5.c -O1 -DPREVENT_OPTIMIZATION line 17 y == 25 FAIL: gcc.dg/guality/pr54519-1.c -O1 -DPREVENT_OPTIMIZATION line 20 x == 36 FAIL: gcc.dg/guality/pr54519-4.c -Os -DPREVENT_OPTIMIZATION line 17 y == 25 FAIL: gcc.dg/guality/pr54519-3.c -O3 -g -DPREVENT_OPTIMIZATION line 23 z == 8 FAIL: gcc.dg/guality/pr54551.c -O2 -DPREVENT_OPTIMIZATION line 18 a == 4 FAIL: gcc.dg/guality/pr54551.c -O1 -DPREVENT_OPTIMIZATION line 18 a == 4 FAIL: gcc.dg/guality/pr54519-1.c -O2 -DPREVENT_OPTIMIZATION line 20 x == 36 FAIL: gcc.dg/guality/pr54693-2.c -Os -DPREVENT_OPTIMIZATION line 21 x == 10 - i FAIL: gcc.dg/guality/pr54519-5.c -O2 -DPREVENT_OPTIMIZATION line 17 y == 25 FAIL: gcc.dg/guality/pr54519-3.c -Os -DPREVENT_OPTIMIZATION line 20 z == 6 FAIL: gcc.dg/guality/pr54519-1.c -Og -DPREVENT_OPTIMIZATION line 23 x == 98 FAIL: gcc.dg/guality/pr54519-3.c -O2 -DPREVENT_OPTIMIZATION line 20 z == 6 FAIL: gcc.dg/guality/pr54551.c -Og -DPREVENT_OPTIMIZATION line 18 a == 4 FAIL: gcc.dg/guality/pr54519-3.c -O2 -DPREVENT_OPTIMIZATION line 23 z == 8 FAIL: gcc.dg/guality/pr54519-4.c -O2 -DPREVENT_OPTIMIZATION line 17 y == 25 FAIL: gcc.dg/guality/pr54519-5.c -Os -DPREVENT_OPTIMIZATION line 17 y == 25 FAIL: gcc.dg/guality/pr54693-2.c -O1 -DPREVENT_OPTIMIZATION line 21 y == 20 - 2 * i FAIL: gcc.dg/guality/pr54519-4.c -O3 -g -DPREVENT_OPTIMIZATION line 17 y == 25 FAIL: gcc.dg/guality/pr54519-5.c -O3 -g -DPREVENT_OPTIMIZATION line 17 y == 25 FAIL: gcc.dg/guality/pr54519-3.c -O3 -g -DPREVENT_OPTIMIZATION line 20 z == 6 FAIL: gcc.dg/guality/pr54519-3.c -Os -DPREVENT_OPTIMIZATION line 23 z == 8 FAIL: gcc.dg/guality/pr54693-2.c -O1 -DPREVENT_OPTIMIZATION line 21 x == 10 - i FAIL: gcc.dg/guality/pr54693-2.c -O3 -fomit-frame-pointer -funroll-loops -fpeel-loops -ftracer -finline-functions -DPREVENT_OPTIMIZATION line 21 y == 20 - 2 * i Fixed by cselib as well as var-tracking patches: FAIL: gcc.dg/guality/pr54519-1.c -Os -DPREVENT_OPTIMIZATION line 23 x == 98 FAIL: gcc.dg/guality/pr54519-1.c -Og -DPREVENT_OPTIMIZATION line 20 y == 25 FAIL: gcc.dg/guality/pr54519-1.c -O1 -DPREVENT_OPTIMIZATION line 20 y == 25 FAIL: gcc.dg/guality/pr54519-2.c -O1 -DPREVENT_OPTIMIZATION line 17 x == 6 FAIL: gcc.dg/guality/pr54519-5.c -O1 -DPREVENT_OPTIMIZATION line 17 x == 6 FAIL: gcc.dg/guality/pr54519-5.c -Og -DPREVENT_OPTIMIZATION line 17 x == 6 FAIL: gcc.dg/guality/pr54519-1.c -Os -DPREVENT_OPTIMIZATION line 20 x == 36 FAIL: gcc.dg/guality/pr54519-2.c -Og -DPREVENT_OPTIMIZATION line 17 x == 6 FAIL: gcc.dg/guality/pr54519-1.c -O1 -DPREVENT_OPTIMIZATION line 23 y == 117 FAIL: gcc.dg/guality/pr54519-1.c -Og -DPREVENT_OPTIMIZATION line 23 y == 117 Fixed only in conjunction of both patches: FAIL: gcc.dg/guality/pr43051-1.c -Os -DPREVENT_OPTIMIZATION line 35 v == 1 FAIL: gcc.dg/guality/pr43051-1.c -Os -DPREVENT_OPTIMIZATION line 40 v == 1 Bootstrapped and regtested on IBM zSystem as well as x86_64. Ok for mainline?