From owner-svn-src-all@freebsd.org Fri Mar 9 09:21:23 2018 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 3B26EF3B629; Fri, 9 Mar 2018 09:21:23 +0000 (UTC) (envelope-from dim@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id E2B826C9E1; Fri, 9 Mar 2018 09:21:22 +0000 (UTC) (envelope-from dim@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id DDB461D5B2; Fri, 9 Mar 2018 09:21:22 +0000 (UTC) (envelope-from dim@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id w299LMfJ057252; Fri, 9 Mar 2018 09:21:22 GMT (envelope-from dim@FreeBSD.org) Received: (from dim@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id w299LMjj057251; Fri, 9 Mar 2018 09:21:22 GMT (envelope-from dim@FreeBSD.org) Message-Id: <201803090921.w299LMjj057251@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: dim set sender to dim@FreeBSD.org using -f From: Dimitry Andric Date: Fri, 9 Mar 2018 09:21:22 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r330686 - head/contrib/llvm/lib/Target/ARM X-SVN-Group: head X-SVN-Commit-Author: dim X-SVN-Commit-Paths: head/contrib/llvm/lib/Target/ARM X-SVN-Commit-Revision: 330686 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 09 Mar 2018 09:21:23 -0000 Author: dim Date: Fri Mar 9 09:21:22 2018 New Revision: 330686 URL: https://svnweb.freebsd.org/changeset/base/330686 Log: Pull in r326882 from upstream llvm trunk (by Sjoerd Meijer): [ARM] Fix for PR36577 Don't PerformSHLSimplify if the given node is used by a node that also uses a constant because we may get stuck in an infinite combine loop. bugzilla: https://bugs.llvm.org/show_bug.cgi?id=36577 Patch by Sam Parker. Differential Revision: https://reviews.llvm.org/D44097 This fixes a hang when compiling one particular file in java/openjdk8 for armv6 and armv7. Reported by: swills PR: 226388 Modified: head/contrib/llvm/lib/Target/ARM/ARMISelLowering.cpp Modified: head/contrib/llvm/lib/Target/ARM/ARMISelLowering.cpp ============================================================================== --- head/contrib/llvm/lib/Target/ARM/ARMISelLowering.cpp Fri Mar 9 05:55:53 2018 (r330685) +++ head/contrib/llvm/lib/Target/ARM/ARMISelLowering.cpp Fri Mar 9 09:21:22 2018 (r330686) @@ -10201,7 +10201,14 @@ static SDValue PerformSHLSimplify(SDNode *N, case ISD::XOR: case ISD::SETCC: case ARMISD::CMP: - // Check that its not already using a shl. + // Check that the user isn't already using a constant because there + // aren't any instructions that support an immediate operand and a + // shifted operand. + if (isa(U->getOperand(0)) || + isa(U->getOperand(1))) + return SDValue(); + + // Check that it's not already using a shift. if (U->getOperand(0).getOpcode() == ISD::SHL || U->getOperand(1).getOpcode() == ISD::SHL) return SDValue(); @@ -10223,8 +10230,6 @@ static SDValue PerformSHLSimplify(SDNode *N, if (!C1ShlC2 || !C2) return SDValue(); - DEBUG(dbgs() << "Trying to simplify shl: "; N->dump()); - APInt C2Int = C2->getAPIntValue(); APInt C1Int = C1ShlC2->getAPIntValue(); @@ -10238,12 +10243,12 @@ static SDValue PerformSHLSimplify(SDNode *N, C1Int.lshrInPlace(C2Int); // The immediates are encoded as an 8-bit value that can be rotated. - unsigned Zeros = C1Int.countLeadingZeros() + C1Int.countTrailingZeros(); - if (C1Int.getBitWidth() - Zeros > 8) - return SDValue(); + auto LargeImm = [](const APInt &Imm) { + unsigned Zeros = Imm.countLeadingZeros() + Imm.countTrailingZeros(); + return Imm.getBitWidth() - Zeros > 8; + }; - Zeros = C2Int.countLeadingZeros() + C2Int.countTrailingZeros(); - if (C2Int.getBitWidth() - Zeros > 8) + if (LargeImm(C1Int) || LargeImm(C2Int)) return SDValue(); SelectionDAG &DAG = DCI.DAG; @@ -10253,6 +10258,10 @@ static SDValue PerformSHLSimplify(SDNode *N, DAG.getConstant(C1Int, dl, MVT::i32)); // Shift left to compensate for the lshr of C1Int. SDValue Res = DAG.getNode(ISD::SHL, dl, MVT::i32, BinOp, SHL.getOperand(1)); + + DEBUG(dbgs() << "Simplify shl use:\n"; SHL.getOperand(0).dump(); SHL.dump(); + N->dump()); + DEBUG(dbgs() << "Into:\n"; X.dump(); BinOp.dump(); Res.dump()); DAG.ReplaceAllUsesWith(SDValue(N, 0), Res); return SDValue(N, 0);