From patchwork Wed May 24 17:32:06 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ajit Agarwal X-Patchwork-Id: 69988 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 18C923858C54 for ; Wed, 24 May 2023 17:35:22 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 18C923858C54 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1684949722; bh=FKqVivcGKWZTpLlnk4LwH5EncKWjduBqIRi7Iw2u/KM=; h=Date:To:Cc:Subject:List-Id:List-Unsubscribe:List-Archive: List-Post:List-Help:List-Subscribe:From:Reply-To:From; b=OkacB8cV+H3q1/0HLORpiV9GQxFlc9ffx+8PApattfaGNQzHlv+H66Yg7ngmLNVlM aVzn2dId2ggYAQ6OhA3SSYNOoOD7BhSe/AlMFTNZ1EJmN76ExxVjHHOhw+q9e/EgAl mke4vaVBIenXfjq/Wmt36mtrEUHEQayBu0sZHXq0= 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 02BDE3858291 for ; Wed, 24 May 2023 17:34:35 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 02BDE3858291 Received: from pps.filterd (m0360083.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 34OHYWh4027281; Wed, 24 May 2023 17:34:35 GMT Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3qspe8rx49-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 24 May 2023 17:34:34 +0000 Received: from m0360083.ppops.net (m0360083.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 34OHYYdb027454; Wed, 24 May 2023 17:34:34 GMT Received: from ppma03wdc.us.ibm.com (ba.79.3fa9.ip4.static.sl-reverse.com [169.63.121.186]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3qspe8rwth-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 24 May 2023 17:34:33 +0000 Received: from pps.filterd (ppma03wdc.us.ibm.com [127.0.0.1]) by ppma03wdc.us.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 34OGP88N009190; Wed, 24 May 2023 17:32:12 GMT Received: from smtprelay07.dal12v.mail.ibm.com ([9.208.130.99]) by ppma03wdc.us.ibm.com (PPS) with ESMTPS id 3qppc5nfh4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 24 May 2023 17:32:12 +0000 Received: from smtpav02.wdc07v.mail.ibm.com (smtpav02.wdc07v.mail.ibm.com [10.39.53.229]) by smtprelay07.dal12v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 34OHWBwD37487348 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 24 May 2023 17:32:11 GMT Received: from smtpav02.wdc07v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6638C5805B; Wed, 24 May 2023 17:32:11 +0000 (GMT) Received: from smtpav02.wdc07v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 77FC95805C; Wed, 24 May 2023 17:32:08 +0000 (GMT) Received: from [9.43.10.207] (unknown [9.43.10.207]) by smtpav02.wdc07v.mail.ibm.com (Postfix) with ESMTP; Wed, 24 May 2023 17:32:07 +0000 (GMT) Message-ID: <7a350840-a339-8292-dfe5-0fe704e85403@linux.ibm.com> Date: Wed, 24 May 2023 23:02:06 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Content-Language: en-US To: gcc-patches Cc: Segher Boessenkool , Peter Bergner , Richard Biener , Jeff Law Subject: [PATCH v3] tree-ssa-sink: Improve code sinking pass X-TM-AS-GCONF: 00 X-Proofpoint-GUID: S74jREed-5rrZzg3GlBpQkWenj991I9D X-Proofpoint-ORIG-GUID: 4pYij9UyBfz2Py8QugFhPrBbv8nQzYqM X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.957,Hydra:6.0.573,FMLib:17.11.176.26 definitions=2023-05-24_11,2023-05-24_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 clxscore=1015 adultscore=0 phishscore=0 spamscore=0 impostorscore=0 bulkscore=0 lowpriorityscore=0 priorityscore=1501 mlxscore=0 mlxlogscore=999 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2304280000 definitions=main-2305240145 X-Spam-Status: No, score=-12.5 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_EF, GIT_PATCH_0, 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 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: Ajit Agarwal via Gcc-patches From: Ajit Agarwal Reply-To: Ajit Agarwal Errors-To: gcc-patches-bounces+patchwork=sourceware.org@gcc.gnu.org Sender: "Gcc-patches" Hello All: This patch improves code sinking pass to sink statements before call to reduce register pressure. Review comments are incorporated. For example : void bar(); int j; void foo(int a, int b, int c, int d, int e, int f) { int l; l = a + b + c + d +e + f; if (a != 5) { bar(); j = l; } } Code Sinking does the following: void bar(); int j; void foo(int a, int b, int c, int d, int e, int f) { int l; if (a != 5) { l = a + b + c + d +e + f; bar(); j = l; } } Bootstrapped regtested on powerpc64-linux-gnu. Thanks & Regards Ajit tree-ssa-sink: Improve code sinking pass Code Sinking sinks the blocks after call.This increases register pressure for callee-saved registers. Improves code sinking before call in the use blocks or immediate dominator of use blocks. 2023-05-24 Ajit Kumar Agarwal gcc/ChangeLog: * tree-ssa-sink.cc (statement_sink_location): Move statements before calls. (def_use_same_block): New function. (select_best_block): Add heuristics to select the best blocks in the immediate post dominator. gcc/testsuite/ChangeLog: * gcc.dg/tree-ssa/ssa-sink-20.c: New testcase. * gcc.dg/tree-ssa/ssa-sink-21.c: New testcase. --- gcc/testsuite/gcc.dg/tree-ssa/ssa-sink-20.c | 15 +++++ gcc/testsuite/gcc.dg/tree-ssa/ssa-sink-21.c | 19 ++++++ gcc/tree-ssa-sink.cc | 74 +++++++++++++++++---- 3 files changed, 96 insertions(+), 12 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ssa-sink-20.c create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ssa-sink-21.c diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-sink-20.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-sink-20.c new file mode 100644 index 00000000000..69fa6d32e7c --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-sink-20.c @@ -0,0 +1,15 @@ +/* { dg-options "-O2 -fdump-tree-optimized -fdump-tree-sink-stats" } */ + +void bar(); +int j; +void foo(int a, int b, int c, int d, int e, int f) +{ + int l; + l = a + b + c + d +e + f; + if (a != 5) + { + bar(); + j = l; + } +} +/* { dg-final { scan-tree-dump-times "Sunk statements: 5" 1 "sink" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-sink-21.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-sink-21.c new file mode 100644 index 00000000000..b34959c8a4d --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-sink-21.c @@ -0,0 +1,19 @@ +/* { dg-options "-O2 -fdump-tree-sink-stats" } */ + +void bar(); +int j, x; +void foo(int a, int b, int c, int d, int e, int f) +{ + int l; + l = a + b + c + d +e + f; + if (a != 5) + { + bar(); + if (b != 3) + x = 3; + else + x = 5; + j = l; + } +} +/* { dg-final { scan-tree-dump-times "Sunk statements: 5" 1 "sink" } } */ diff --git a/gcc/tree-ssa-sink.cc b/gcc/tree-ssa-sink.cc index b1ba7a2ad6c..ee8988bbb2c 100644 --- a/gcc/tree-ssa-sink.cc +++ b/gcc/tree-ssa-sink.cc @@ -171,9 +171,28 @@ nearest_common_dominator_of_uses (def_operand_p def_p, bool *debug_stmts) return commondom; } +/* Return TRUE if immediate uses of the defs in + STMT occur in the same block as STMT, FALSE otherwise. */ + +bool +def_use_same_block (gimple *stmt) +{ + def_operand_p def; + ssa_op_iter iter; + + FOR_EACH_SSA_DEF_OPERAND (def, stmt, iter, SSA_OP_DEF) + { + gimple *def_stmt = SSA_NAME_DEF_STMT (DEF_FROM_PTR (def)); + if ((gimple_bb (def_stmt) == gimple_bb (stmt))) + return true; + } + return false; +} + /* Given EARLY_BB and LATE_BB, two blocks in a path through the dominator tree, return the best basic block between them (inclusive) to place - statements. + statements. The best basic block should be in immediate dominator of + best basic block if the use stmt is after the call. We want the most control dependent block in the shallowest loop nest. @@ -190,7 +209,8 @@ nearest_common_dominator_of_uses (def_operand_p def_p, bool *debug_stmts) static basic_block select_best_block (basic_block early_bb, basic_block late_bb, - gimple *stmt) + gimple *stmt, + gimple *use) { basic_block best_bb = late_bb; basic_block temp_bb = late_bb; @@ -230,14 +250,46 @@ select_best_block (basic_block early_bb, if (threshold > 100) threshold = 100; } - /* If BEST_BB is at the same nesting level, then require it to have significantly lower execution frequency to avoid gratuitous movement. */ if (bb_loop_depth (best_bb) == bb_loop_depth (early_bb) /* If result of comparsion is unknown, prefer EARLY_BB. Thus use !(...>=..) rather than (...<...) */ && !(best_bb->count * 100 >= early_bb->count * threshold)) - return best_bb; + { + basic_block new_best_bb = get_immediate_dominator (CDI_DOMINATORS, best_bb); + /* Return best_bb if def and use are in same block otherwise new_best_bb. + + Things to consider: + + new_best_bb is not equal to best_bb and early_bb. + + stmt is not call. + + new_best_bb doesnt have any phis. + + use basic block is not equal to early_bb. + + use basic block post dominates to new_best_bb. + + new_best_bb dominates early_bb. */ + if (new_best_bb && use + && (new_best_bb != best_bb) + && (new_best_bb != early_bb) + && !is_gimple_call (stmt) + && gsi_end_p (gsi_start_phis (new_best_bb)) + && (gimple_bb (use) != early_bb) + && !is_gimple_call (use) + && dominated_by_p (CDI_POST_DOMINATORS, new_best_bb, gimple_bb(use)) + && dominated_by_p (CDI_DOMINATORS, new_best_bb, early_bb)) + { + if (def_use_same_block (use)) + return best_bb; + + return new_best_bb; + } + return best_bb; + } /* No better block found, so return EARLY_BB, which happens to be the statement's original block. */ @@ -382,7 +434,7 @@ statement_sink_location (gimple *stmt, basic_block frombb, { /* Do not sink loads from hard registers. */ if (gimple_assign_single_p (stmt) - && VAR_P (gimple_assign_rhs1 (stmt)) + && TREE_CODE (gimple_assign_rhs1 (stmt)) == VAR_DECL && DECL_HARD_REGISTER (gimple_assign_rhs1 (stmt))) return false; @@ -439,7 +491,7 @@ statement_sink_location (gimple *stmt, basic_block frombb, if (!dominated_by_p (CDI_DOMINATORS, commondom, frombb)) return false; - commondom = select_best_block (frombb, commondom, stmt); + commondom = select_best_block (frombb, commondom, stmt, NULL); if (commondom == frombb) return false; @@ -456,19 +508,17 @@ statement_sink_location (gimple *stmt, basic_block frombb, continue; break; } + use = USE_STMT (one_use); if (gimple_code (use) != GIMPLE_PHI) { - sinkbb = select_best_block (frombb, gimple_bb (use), stmt); + sinkbb = select_best_block (frombb, gimple_bb (use), stmt, use); if (sinkbb == frombb) return false; - if (sinkbb == gimple_bb (use)) - *togsi = gsi_for_stmt (use); - else - *togsi = gsi_after_labels (sinkbb); + *togsi = gsi_after_labels (sinkbb); return true; } @@ -480,7 +530,7 @@ statement_sink_location (gimple *stmt, basic_block frombb, if (!sinkbb) return false; - sinkbb = select_best_block (frombb, sinkbb, stmt); + sinkbb = select_best_block (frombb, sinkbb, stmt, NULL); if (!sinkbb || sinkbb == frombb) return false;