From owner-svn-src-head@FreeBSD.ORG Fri Aug 30 18:29:26 2013 Return-Path: Delivered-To: svn-src-head@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 8058CFFE; Fri, 30 Aug 2013 18:29:26 +0000 (UTC) (envelope-from dim@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:1900:2254:2068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 51D5526F8; Fri, 30 Aug 2013 18:29:26 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.7/8.14.7) with ESMTP id r7UITQuM021817; Fri, 30 Aug 2013 18:29:26 GMT (envelope-from dim@svn.freebsd.org) Received: (from dim@localhost) by svn.freebsd.org (8.14.7/8.14.5/Submit) id r7UITQwX021816; Fri, 30 Aug 2013 18:29:26 GMT (envelope-from dim@svn.freebsd.org) Message-Id: <201308301829.r7UITQwX021816@svn.freebsd.org> From: Dimitry Andric Date: Fri, 30 Aug 2013 18:29:26 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r255076 - head/contrib/llvm/lib/Transforms/InstCombine X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 30 Aug 2013 18:29:26 -0000 Author: dim Date: Fri Aug 30 18:29:25 2013 New Revision: 255076 URL: http://svnweb.freebsd.org/changeset/base/255076 Log: Pull in r189672 from upstream llvm trunk: InstCombine: Check for zero shift amounts before subtracting one causing integer overflow. PR17026. Also avoid undefined shifts and shift amounts larger than 64 bits (those are always undef because we can't represent integer types that large). This should fix assertion failures when building the emulators/xmame port. Reported by: bapt Modified: head/contrib/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp Modified: head/contrib/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp ============================================================================== --- head/contrib/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp Fri Aug 30 17:47:53 2013 (r255075) +++ head/contrib/llvm/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp Fri Aug 30 18:29:25 2013 (r255076) @@ -845,21 +845,26 @@ Value *InstCombiner::SimplifyDemandedUse Value *InstCombiner::SimplifyShrShlDemandedBits(Instruction *Shr, Instruction *Shl, APInt DemandedMask, APInt &KnownZero, APInt &KnownOne) { - unsigned ShlAmt = cast(Shl->getOperand(1))->getZExtValue(); - unsigned ShrAmt = cast(Shr->getOperand(1))->getZExtValue(); + const APInt &ShlOp1 = cast(Shl->getOperand(1))->getValue(); + const APInt &ShrOp1 = cast(Shr->getOperand(1))->getValue(); + if (!ShlOp1 || !ShrOp1) + return 0; // Noop. + + Value *VarX = Shr->getOperand(0); + Type *Ty = VarX->getType(); + unsigned BitWidth = Ty->getIntegerBitWidth(); + if (ShlOp1.uge(BitWidth) || ShrOp1.uge(BitWidth)) + return 0; // Undef. + + unsigned ShlAmt = ShlOp1.getZExtValue(); + unsigned ShrAmt = ShrOp1.getZExtValue(); KnownOne.clearAllBits(); KnownZero = APInt::getBitsSet(KnownZero.getBitWidth(), 0, ShlAmt-1); KnownZero &= DemandedMask; - if (ShlAmt == 0 || ShrAmt == 0) - return 0; - - Value *VarX = Shr->getOperand(0); - Type *Ty = VarX->getType(); - - APInt BitMask1(APInt::getAllOnesValue(Ty->getIntegerBitWidth())); - APInt BitMask2(APInt::getAllOnesValue(Ty->getIntegerBitWidth())); + APInt BitMask1(APInt::getAllOnesValue(BitWidth)); + APInt BitMask2(APInt::getAllOnesValue(BitWidth)); bool isLshr = (Shr->getOpcode() == Instruction::LShr); BitMask1 = isLshr ? (BitMask1.lshr(ShrAmt) << ShlAmt) :