diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/SelectionDAG.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 169 |
1 files changed, 61 insertions, 108 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 48f8f773be..305eee81cd 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -1627,7 +1627,7 @@ bool SelectionDAG::SignBitIsZero(SDValue Op, unsigned Depth) const { bool SelectionDAG::MaskedValueIsZero(SDValue Op, const APInt &Mask, unsigned Depth) const { APInt KnownZero, KnownOne; - ComputeMaskedBits(Op, Mask, KnownZero, KnownOne, Depth); + ComputeMaskedBits(Op, KnownZero, KnownOne, Depth); assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); return (KnownZero & Mask) == Mask; } @@ -1636,15 +1636,12 @@ bool SelectionDAG::MaskedValueIsZero(SDValue Op, const APInt &Mask, /// known to be either zero or one and return them in the KnownZero/KnownOne /// bitsets. This code only analyzes bits in Mask, in order to short-circuit /// processing. -void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, - APInt &KnownZero, APInt &KnownOne, - unsigned Depth) const { - unsigned BitWidth = Mask.getBitWidth(); - assert(BitWidth == Op.getValueType().getScalarType().getSizeInBits() && - "Mask size mismatches value type size!"); +void SelectionDAG::ComputeMaskedBits(SDValue Op, APInt &KnownZero, + APInt &KnownOne, unsigned Depth) const { + unsigned BitWidth = Op.getValueType().getScalarType().getSizeInBits(); KnownZero = KnownOne = APInt(BitWidth, 0); // Don't know anything. - if (Depth == 6 || Mask == 0) + if (Depth == 6) return; // Limit search depth. APInt KnownZero2, KnownOne2; @@ -1652,14 +1649,13 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, switch (Op.getOpcode()) { case ISD::Constant: // We know all of the bits for a constant! - KnownOne = cast<ConstantSDNode>(Op)->getAPIntValue() & Mask; - KnownZero = ~KnownOne & Mask; + KnownOne = cast<ConstantSDNode>(Op)->getAPIntValue(); + KnownZero = ~KnownOne; return; case ISD::AND: // If either the LHS or the RHS are Zero, the result is zero. - ComputeMaskedBits(Op.getOperand(1), Mask, KnownZero, KnownOne, Depth+1); - ComputeMaskedBits(Op.getOperand(0), Mask & ~KnownZero, - KnownZero2, KnownOne2, Depth+1); + ComputeMaskedBits(Op.getOperand(1), KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero2, KnownOne2, Depth+1); assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?"); @@ -1669,9 +1665,8 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, KnownZero |= KnownZero2; return; case ISD::OR: - ComputeMaskedBits(Op.getOperand(1), Mask, KnownZero, KnownOne, Depth+1); - ComputeMaskedBits(Op.getOperand(0), Mask & ~KnownOne, - KnownZero2, KnownOne2, Depth+1); + ComputeMaskedBits(Op.getOperand(1), KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero2, KnownOne2, Depth+1); assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?"); @@ -1681,8 +1676,8 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, KnownOne |= KnownOne2; return; case ISD::XOR: { - ComputeMaskedBits(Op.getOperand(1), Mask, KnownZero, KnownOne, Depth+1); - ComputeMaskedBits(Op.getOperand(0), Mask, KnownZero2, KnownOne2, Depth+1); + ComputeMaskedBits(Op.getOperand(1), KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero2, KnownOne2, Depth+1); assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?"); @@ -1694,9 +1689,8 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, return; } case ISD::MUL: { - APInt Mask2 = APInt::getAllOnesValue(BitWidth); - ComputeMaskedBits(Op.getOperand(1), Mask2, KnownZero, KnownOne, Depth+1); - ComputeMaskedBits(Op.getOperand(0), Mask2, KnownZero2, KnownOne2, Depth+1); + ComputeMaskedBits(Op.getOperand(1), KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero2, KnownOne2, Depth+1); assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?"); @@ -1715,33 +1709,29 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, LeadZ = std::min(LeadZ, BitWidth); KnownZero = APInt::getLowBitsSet(BitWidth, TrailZ) | APInt::getHighBitsSet(BitWidth, LeadZ); - KnownZero &= Mask; return; } case ISD::UDIV: { // For the purposes of computing leading zeros we can conservatively // treat a udiv as a logical right shift by the power of 2 known to // be less than the denominator. - APInt AllOnes = APInt::getAllOnesValue(BitWidth); - ComputeMaskedBits(Op.getOperand(0), - AllOnes, KnownZero2, KnownOne2, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero2, KnownOne2, Depth+1); unsigned LeadZ = KnownZero2.countLeadingOnes(); KnownOne2.clearAllBits(); KnownZero2.clearAllBits(); - ComputeMaskedBits(Op.getOperand(1), - AllOnes, KnownZero2, KnownOne2, Depth+1); + ComputeMaskedBits(Op.getOperand(1), KnownZero2, KnownOne2, Depth+1); unsigned RHSUnknownLeadingOnes = KnownOne2.countLeadingZeros(); if (RHSUnknownLeadingOnes != BitWidth) LeadZ = std::min(BitWidth, LeadZ + BitWidth - RHSUnknownLeadingOnes - 1); - KnownZero = APInt::getHighBitsSet(BitWidth, LeadZ) & Mask; + KnownZero = APInt::getHighBitsSet(BitWidth, LeadZ); return; } case ISD::SELECT: - ComputeMaskedBits(Op.getOperand(2), Mask, KnownZero, KnownOne, Depth+1); - ComputeMaskedBits(Op.getOperand(1), Mask, KnownZero2, KnownOne2, Depth+1); + ComputeMaskedBits(Op.getOperand(2), KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(1), KnownZero2, KnownOne2, Depth+1); assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?"); @@ -1750,8 +1740,8 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, KnownZero &= KnownZero2; return; case ISD::SELECT_CC: - ComputeMaskedBits(Op.getOperand(3), Mask, KnownZero, KnownOne, Depth+1); - ComputeMaskedBits(Op.getOperand(2), Mask, KnownZero2, KnownOne2, Depth+1); + ComputeMaskedBits(Op.getOperand(3), KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(2), KnownZero2, KnownOne2, Depth+1); assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?"); @@ -1783,8 +1773,7 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, if (ShAmt >= BitWidth) return; - ComputeMaskedBits(Op.getOperand(0), Mask.lshr(ShAmt), - KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero, KnownOne, Depth+1); assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); KnownZero <<= ShAmt; KnownOne <<= ShAmt; @@ -1801,13 +1790,12 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, if (ShAmt >= BitWidth) return; - ComputeMaskedBits(Op.getOperand(0), (Mask << ShAmt), - KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero, KnownOne, Depth+1); assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); KnownZero = KnownZero.lshr(ShAmt); KnownOne = KnownOne.lshr(ShAmt); - APInt HighBits = APInt::getHighBitsSet(BitWidth, ShAmt) & Mask; + APInt HighBits = APInt::getHighBitsSet(BitWidth, ShAmt); KnownZero |= HighBits; // High bits known zero. } return; @@ -1819,15 +1807,11 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, if (ShAmt >= BitWidth) return; - APInt InDemandedMask = (Mask << ShAmt); // If any of the demanded bits are produced by the sign extension, we also // demand the input sign bit. - APInt HighBits = APInt::getHighBitsSet(BitWidth, ShAmt) & Mask; - if (HighBits.getBoolValue()) - InDemandedMask |= APInt::getSignBit(BitWidth); + APInt HighBits = APInt::getHighBitsSet(BitWidth, ShAmt); - ComputeMaskedBits(Op.getOperand(0), InDemandedMask, KnownZero, KnownOne, - Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero, KnownOne, Depth+1); assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); KnownZero = KnownZero.lshr(ShAmt); KnownOne = KnownOne.lshr(ShAmt); @@ -1849,10 +1833,10 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, // Sign extension. Compute the demanded bits in the result that are not // present in the input. - APInt NewBits = APInt::getHighBitsSet(BitWidth, BitWidth - EBits) & Mask; + APInt NewBits = APInt::getHighBitsSet(BitWidth, BitWidth - EBits); APInt InSignBit = APInt::getSignBit(EBits); - APInt InputDemandedBits = Mask & APInt::getLowBitsSet(BitWidth, EBits); + APInt InputDemandedBits = APInt::getLowBitsSet(BitWidth, EBits); // If the sign extended bits are demanded, we know that the sign // bit is demanded. @@ -1860,8 +1844,9 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, if (NewBits.getBoolValue()) InputDemandedBits |= InSignBit; - ComputeMaskedBits(Op.getOperand(0), InputDemandedBits, - KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero, KnownOne, Depth+1); + KnownOne &= InputDemandedBits; + KnownZero &= InputDemandedBits; assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); // If the sign bit of the input is known set or clear, then we know the @@ -1893,20 +1878,19 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, if (ISD::isZEXTLoad(Op.getNode())) { EVT VT = LD->getMemoryVT(); unsigned MemBits = VT.getScalarType().getSizeInBits(); - KnownZero |= APInt::getHighBitsSet(BitWidth, BitWidth - MemBits) & Mask; + KnownZero |= APInt::getHighBitsSet(BitWidth, BitWidth - MemBits); } else if (const MDNode *Ranges = LD->getRanges()) { - computeMaskedBitsLoad(*Ranges, Mask, KnownZero); + computeMaskedBitsLoad(*Ranges, KnownZero); } return; } case ISD::ZERO_EXTEND: { EVT InVT = Op.getOperand(0).getValueType(); unsigned InBits = InVT.getScalarType().getSizeInBits(); - APInt NewBits = APInt::getHighBitsSet(BitWidth, BitWidth - InBits) & Mask; - APInt InMask = Mask.trunc(InBits); + APInt NewBits = APInt::getHighBitsSet(BitWidth, BitWidth - InBits); KnownZero = KnownZero.trunc(InBits); KnownOne = KnownOne.trunc(InBits); - ComputeMaskedBits(Op.getOperand(0), InMask, KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero, KnownOne, Depth+1); KnownZero = KnownZero.zext(BitWidth); KnownOne = KnownOne.zext(BitWidth); KnownZero |= NewBits; @@ -1916,17 +1900,11 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, EVT InVT = Op.getOperand(0).getValueType(); unsigned InBits = InVT.getScalarType().getSizeInBits(); APInt InSignBit = APInt::getSignBit(InBits); - APInt NewBits = APInt::getHighBitsSet(BitWidth, BitWidth - InBits) & Mask; - APInt InMask = Mask.trunc(InBits); - - // If any of the sign extended bits are demanded, we know that the sign - // bit is demanded. Temporarily set this bit in the mask for our callee. - if (NewBits.getBoolValue()) - InMask |= InSignBit; + APInt NewBits = APInt::getHighBitsSet(BitWidth, BitWidth - InBits); KnownZero = KnownZero.trunc(InBits); KnownOne = KnownOne.trunc(InBits); - ComputeMaskedBits(Op.getOperand(0), InMask, KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero, KnownOne, Depth+1); // Note if the sign bit is known to be zero or one. bool SignBitKnownZero = KnownZero.isNegative(); @@ -1934,13 +1912,6 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, assert(!(SignBitKnownZero && SignBitKnownOne) && "Sign bit can't be known to be both zero and one!"); - // If the sign bit wasn't actually demanded by our caller, we don't - // want it set in the KnownZero and KnownOne result values. Reset the - // mask and reapply it to the result values. - InMask = Mask.trunc(InBits); - KnownZero &= InMask; - KnownOne &= InMask; - KnownZero = KnownZero.zext(BitWidth); KnownOne = KnownOne.zext(BitWidth); @@ -1954,10 +1925,9 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, case ISD::ANY_EXTEND: { EVT InVT = Op.getOperand(0).getValueType(); unsigned InBits = InVT.getScalarType().getSizeInBits(); - APInt InMask = Mask.trunc(InBits); KnownZero = KnownZero.trunc(InBits); KnownOne = KnownOne.trunc(InBits); - ComputeMaskedBits(Op.getOperand(0), InMask, KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero, KnownOne, Depth+1); KnownZero = KnownZero.zext(BitWidth); KnownOne = KnownOne.zext(BitWidth); return; @@ -1965,10 +1935,9 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, case ISD::TRUNCATE: { EVT InVT = Op.getOperand(0).getValueType(); unsigned InBits = InVT.getScalarType().getSizeInBits(); - APInt InMask = Mask.zext(InBits); KnownZero = KnownZero.zext(InBits); KnownOne = KnownOne.zext(InBits); - ComputeMaskedBits(Op.getOperand(0), InMask, KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero, KnownOne, Depth+1); assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?"); KnownZero = KnownZero.trunc(BitWidth); KnownOne = KnownOne.trunc(BitWidth); @@ -1977,9 +1946,8 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, case ISD::AssertZext: { EVT VT = cast<VTSDNode>(Op.getOperand(1))->getVT(); APInt InMask = APInt::getLowBitsSet(BitWidth, VT.getSizeInBits()); - ComputeMaskedBits(Op.getOperand(0), Mask & InMask, KnownZero, - KnownOne, Depth+1); - KnownZero |= (~InMask) & Mask; + ComputeMaskedBits(Op.getOperand(0), KnownZero, KnownOne, Depth+1); + KnownZero |= (~InMask); return; } case ISD::FGETSIGN: @@ -1996,8 +1964,7 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, unsigned NLZ = (CLHS->getAPIntValue()+1).countLeadingZeros(); // NLZ can't be BitWidth with no sign bit APInt MaskV = APInt::getHighBitsSet(BitWidth, NLZ+1); - ComputeMaskedBits(Op.getOperand(1), MaskV, KnownZero2, KnownOne2, - Depth+1); + ComputeMaskedBits(Op.getOperand(1), KnownZero2, KnownOne2, Depth+1); // If all of the MaskV bits are known to be zero, then we know the // output top bits are zero, because we now know that the output is @@ -2005,7 +1972,7 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, if ((KnownZero2 & MaskV) == MaskV) { unsigned NLZ2 = CLHS->getAPIntValue().countLeadingZeros(); // Top bits known zero. - KnownZero = APInt::getHighBitsSet(BitWidth, NLZ2) & Mask; + KnownZero = APInt::getHighBitsSet(BitWidth, NLZ2); } } } @@ -2016,13 +1983,11 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, // Output known-0 bits are known if clear or set in both the low clear bits // common to both LHS & RHS. For example, 8+(X<<3) is known to have the // low 3 bits clear. - APInt Mask2 = APInt::getLowBitsSet(BitWidth, - BitWidth - Mask.countLeadingZeros()); - ComputeMaskedBits(Op.getOperand(0), Mask2, KnownZero2, KnownOne2, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero2, KnownOne2, Depth+1); assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?"); unsigned KnownZeroOut = KnownZero2.countTrailingOnes(); - ComputeMaskedBits(Op.getOperand(1), Mask2, KnownZero2, KnownOne2, Depth+1); + ComputeMaskedBits(Op.getOperand(1), KnownZero2, KnownOne2, Depth+1); assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?"); KnownZeroOut = std::min(KnownZeroOut, KnownZero2.countTrailingOnes()); @@ -2046,7 +2011,7 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, if (RA.isPowerOf2()) { APInt LowBits = RA - 1; APInt Mask2 = LowBits | APInt::getSignBit(BitWidth); - ComputeMaskedBits(Op.getOperand(0), Mask2,KnownZero2,KnownOne2,Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero2,KnownOne2,Depth+1); // The low bits of the first operand are unchanged by the srem. KnownZero = KnownZero2 & LowBits; @@ -2061,10 +2026,6 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, // the upper bits are all one. if (KnownOne2[BitWidth-1] && ((KnownOne2 & LowBits) != 0)) KnownOne |= ~LowBits; - - KnownZero &= Mask; - KnownOne &= Mask; - assert((KnownZero & KnownOne) == 0&&"Bits known to be one AND zero?"); } } @@ -2074,9 +2035,8 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, const APInt &RA = Rem->getAPIntValue(); if (RA.isPowerOf2()) { APInt LowBits = (RA - 1); - APInt Mask2 = LowBits & Mask; - KnownZero |= ~LowBits & Mask; - ComputeMaskedBits(Op.getOperand(0), Mask2, KnownZero, KnownOne,Depth+1); + KnownZero |= ~LowBits; + ComputeMaskedBits(Op.getOperand(0), KnownZero, KnownOne,Depth+1); assert((KnownZero & KnownOne) == 0&&"Bits known to be one AND zero?"); break; } @@ -2084,16 +2044,13 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, // Since the result is less than or equal to either operand, any leading // zero bits in either operand must also exist in the result. - APInt AllOnes = APInt::getAllOnesValue(BitWidth); - ComputeMaskedBits(Op.getOperand(0), AllOnes, KnownZero, KnownOne, - Depth+1); - ComputeMaskedBits(Op.getOperand(1), AllOnes, KnownZero2, KnownOne2, - Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(1), KnownZero2, KnownOne2, Depth+1); uint32_t Leaders = std::max(KnownZero.countLeadingOnes(), KnownZero2.countLeadingOnes()); KnownOne.clearAllBits(); - KnownZero = APInt::getHighBitsSet(BitWidth, Leaders) & Mask; + KnownZero = APInt::getHighBitsSet(BitWidth, Leaders); return; } case ISD::FrameIndex: @@ -2113,8 +2070,7 @@ void SelectionDAG::ComputeMaskedBits(SDValue Op, const APInt &Mask, case ISD::INTRINSIC_W_CHAIN: case ISD::INTRINSIC_VOID: // Allow the target to implement this method for its nodes. - TLI.computeMaskedBitsForTargetNode(Op, Mask, KnownZero, KnownOne, *this, - Depth); + TLI.computeMaskedBitsForTargetNode(Op, KnownZero, KnownOne, *this, Depth); return; } } @@ -2238,12 +2194,11 @@ unsigned SelectionDAG::ComputeNumSignBits(SDValue Op, unsigned Depth) const{ if (ConstantSDNode *CRHS = dyn_cast<ConstantSDNode>(Op.getOperand(1))) if (CRHS->isAllOnesValue()) { APInt KnownZero, KnownOne; - APInt Mask = APInt::getAllOnesValue(VTBits); - ComputeMaskedBits(Op.getOperand(0), Mask, KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(0), KnownZero, KnownOne, Depth+1); // If the input is known to be 0 or 1, the output is 0/-1, which is all // sign bits set. - if ((KnownZero | APInt(VTBits, 1)) == Mask) + if ((KnownZero | APInt(VTBits, 1)).isAllOnesValue()) return VTBits; // If we are subtracting one from a positive number, there is no carry @@ -2264,11 +2219,10 @@ unsigned SelectionDAG::ComputeNumSignBits(SDValue Op, unsigned Depth) const{ if (ConstantSDNode *CLHS = dyn_cast<ConstantSDNode>(Op.getOperand(0))) if (CLHS->isNullValue()) { APInt KnownZero, KnownOne; - APInt Mask = APInt::getAllOnesValue(VTBits); - ComputeMaskedBits(Op.getOperand(1), Mask, KnownZero, KnownOne, Depth+1); + ComputeMaskedBits(Op.getOperand(1), KnownZero, KnownOne, Depth+1); // If the input is known to be 0 or 1, the output is 0/-1, which is all // sign bits set. - if ((KnownZero | APInt(VTBits, 1)) == Mask) + if ((KnownZero | APInt(VTBits, 1)).isAllOnesValue()) return VTBits; // If the input is known to be positive (the sign bit is known clear), @@ -2317,9 +2271,9 @@ unsigned SelectionDAG::ComputeNumSignBits(SDValue Op, unsigned Depth) const{ // Finally, if we can prove that the top bits of the result are 0's or 1's, // use this information. APInt KnownZero, KnownOne; - APInt Mask = APInt::getAllOnesValue(VTBits); - ComputeMaskedBits(Op, Mask, KnownZero, KnownOne, Depth); + ComputeMaskedBits(Op, KnownZero, KnownOne, Depth); + APInt Mask; if (KnownZero.isNegative()) { // sign bit is 0 Mask = KnownZero; } else if (KnownOne.isNegative()) { // sign bit is 1; @@ -6040,10 +5994,9 @@ unsigned SelectionDAG::InferPtrAlignment(SDValue Ptr) const { int64_t GVOffset = 0; if (TLI.isGAPlusOffset(Ptr.getNode(), GV, GVOffset)) { unsigned PtrWidth = TLI.getPointerTy().getSizeInBits(); - APInt AllOnes = APInt::getAllOnesValue(PtrWidth); APInt KnownZero(PtrWidth, 0), KnownOne(PtrWidth, 0); - llvm::ComputeMaskedBits(const_cast<GlobalValue*>(GV), AllOnes, - KnownZero, KnownOne, TLI.getTargetData()); + llvm::ComputeMaskedBits(const_cast<GlobalValue*>(GV), KnownZero, KnownOne, + TLI.getTargetData()); unsigned AlignBits = KnownZero.countTrailingOnes(); unsigned Align = AlignBits ? 1 << std::min(31U, AlignBits) : 0; if (Align) |