From patchwork Thu Dec 22 10:30:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jakub Jelinek X-Patchwork-Id: 62255 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 65C623857BB3 for ; Thu, 22 Dec 2022 10:30:45 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 65C623857BB3 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1671705045; bh=iRBOWLhtzbdBoY9fYa1EnR6jJ/SPRMuKVCEBSgUsjsE=; h=Date:To:Cc:Subject:List-Id:List-Unsubscribe:List-Archive: List-Post:List-Help:List-Subscribe:From:Reply-To:From; b=o4VfZ3As5+TJVqOzgulrdhlKn0Oq57GexB6kzGpQTZKxL8ZRXPtZeWHOK/bwHP5N1 K22iocXvP4voGZLr4gZNiK5m6eKUcFJBIMYSesnwlskMoEFp8WW+0y6PToPhY3JpTh tfsLSiNdrxCmoZoiC9qhL33qfCd4wcsVcHMvIZ+4= X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id 8AFC33858425 for ; Thu, 22 Dec 2022 10:30:17 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 8AFC33858425 Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-349-ZWXoqpj9NCC5eK9F8Urh8A-1; Thu, 22 Dec 2022 05:30:15 -0500 X-MC-Unique: ZWXoqpj9NCC5eK9F8Urh8A-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 21B89101A521; Thu, 22 Dec 2022 10:30:15 +0000 (UTC) Received: from tucnak.zalov.cz (unknown [10.39.195.114]) by smtp.corp.redhat.com (Postfix) with ESMTPS id ABE0853A0; Thu, 22 Dec 2022 10:30:14 +0000 (UTC) Received: from tucnak.zalov.cz (localhost [127.0.0.1]) by tucnak.zalov.cz (8.17.1/8.17.1) with ESMTPS id 2BMAUAWs1189295 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Thu, 22 Dec 2022 11:30:11 +0100 Received: (from jakub@localhost) by tucnak.zalov.cz (8.17.1/8.17.1/Submit) id 2BMAUAmT1189294; Thu, 22 Dec 2022 11:30:10 +0100 Date: Thu, 22 Dec 2022 11:30:09 +0100 To: Richard Biener Cc: gcc-patches@gcc.gnu.org, Aldy Hernandez , Andrew MacLeod Subject: [PATCH] phiopt: Drop SSA_NAME_RANGE_INFO in maybe equal case [PR108166] Message-ID: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline X-Spam-Status: No, score=-3.5 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_NONE, 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-Patchwork-Original-From: Jakub Jelinek via Gcc-patches From: Jakub Jelinek Reply-To: Jakub Jelinek Errors-To: gcc-patches-bounces+patchwork=sourceware.org@gcc.gnu.org Sender: "Gcc-patches" Hi! The following place in value_replacement is after proving that x == cst1 ? cst2 : x phi result is only used in a comparison with constant which doesn't care if it compares cst1 or cst2 and replaces it with x. The testcase is miscompiled because we have after the replacement incorrect range info for the phi result, we would need to effectively union the phi result range with cst1 (oarg in the code) because previously that constant might be missing in the range, but newly it can appear (we've just verified that the single use stmt of the phi result doesn't care about that value in particular). The following patch just resets the info, bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? Aldy/Andrew, how would one instead union the SSA_NAME_RANGE_INFO with some INTEGER_CST and store it back into SSA_NAME_RANGE_INFO (including adjusting non-zero bits and the like)? 2022-12-22 Jakub Jelinek PR tree-optimization/108166 * tree-ssa-phiopt.cc (value_replacement): For the maybe_equal_p case turned into equal_p reset SSA_NAME_RANGE_INFO of phi result. * g++.dg/torture/pr108166.C: New test. Jakub --- gcc/tree-ssa-phiopt.cc.jj 2022-10-28 11:00:53.970243821 +0200 +++ gcc/tree-ssa-phiopt.cc 2022-12-21 14:27:58.118326548 +0100 @@ -1491,6 +1491,12 @@ value_replacement (basic_block cond_bb, default: break; } + if (equal_p) + /* After the optimization PHI result can have value + which it couldn't have previously. + We could instead of resetting it union the range + info with oarg. */ + reset_flow_sensitive_info (gimple_phi_result (phi)); if (equal_p && MAY_HAVE_DEBUG_BIND_STMTS) { imm_use_iterator imm_iter; --- gcc/testsuite/g++.dg/torture/pr108166.C.jj 2022-12-21 14:31:02.638661322 +0100 +++ gcc/testsuite/g++.dg/torture/pr108166.C 2022-12-21 14:30:45.441909725 +0100 @@ -0,0 +1,26 @@ +// PR tree-optimization/108166 +// { dg-do run } + +bool a, b; +int d, c; + +const int & +foo (const int &f, const int &g) +{ + return !f ? f : g; +} + +__attribute__((noipa)) void +bar (int) +{ +} + +int +main () +{ + c = foo (b, 0) > ((b ? d : b) ?: 8); + a = b ? d : b; + bar (a); + if (a != 0) + __builtin_abort (); +}