diff options
Diffstat (limited to 'llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 25 |
1 files changed, 10 insertions, 15 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index a71cf82cd58..e03668777d8 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -1452,16 +1452,14 @@ SDValue DAGCombiner::visitADD(SDNode *N) { if (VT.isInteger() && !VT.isVector()) { APInt LHSZero, LHSOne; APInt RHSZero, RHSOne; - APInt Mask = APInt::getAllOnesValue(VT.getScalarType().getSizeInBits()); - DAG.ComputeMaskedBits(N0, Mask, LHSZero, LHSOne); + DAG.ComputeMaskedBits(N0, LHSZero, LHSOne); if (LHSZero.getBoolValue()) { - DAG.ComputeMaskedBits(N1, Mask, RHSZero, RHSOne); + DAG.ComputeMaskedBits(N1, RHSZero, RHSOne); // If all possibly-set bits on the LHS are clear on the RHS, return an OR. // If all possibly-set bits on the RHS are clear on the LHS, return an OR. - if ((RHSZero & (~LHSZero & Mask)) == (~LHSZero & Mask) || - (LHSZero & (~RHSZero & Mask)) == (~RHSZero & Mask)) + if ((RHSZero & ~LHSZero) == ~LHSZero || (LHSZero & ~RHSZero) == ~RHSZero) return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N1); } } @@ -1547,16 +1545,14 @@ SDValue DAGCombiner::visitADDC(SDNode *N) { // fold (addc a, b) -> (or a, b), CARRY_FALSE iff a and b share no bits. APInt LHSZero, LHSOne; APInt RHSZero, RHSOne; - APInt Mask = APInt::getAllOnesValue(VT.getScalarType().getSizeInBits()); - DAG.ComputeMaskedBits(N0, Mask, LHSZero, LHSOne); + DAG.ComputeMaskedBits(N0, LHSZero, LHSOne); if (LHSZero.getBoolValue()) { - DAG.ComputeMaskedBits(N1, Mask, RHSZero, RHSOne); + DAG.ComputeMaskedBits(N1, RHSZero, RHSOne); // If all possibly-set bits on the LHS are clear on the RHS, return an OR. // If all possibly-set bits on the RHS are clear on the LHS, return an OR. - if ((RHSZero & (~LHSZero & Mask)) == (~LHSZero & Mask) || - (LHSZero & (~RHSZero & Mask)) == (~RHSZero & Mask)) + if ((RHSZero & ~LHSZero) == ~LHSZero || (LHSZero & ~RHSZero) == ~RHSZero) return CombineTo(N, DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N1), DAG.getNode(ISD::CARRY_FALSE, N->getDebugLoc(), MVT::Glue)); @@ -3835,8 +3831,7 @@ SDValue DAGCombiner::visitSRL(SDNode *N) { if (N1C && N0.getOpcode() == ISD::CTLZ && N1C->getAPIntValue() == Log2_32(VT.getSizeInBits())) { APInt KnownZero, KnownOne; - APInt Mask = APInt::getAllOnesValue(VT.getScalarType().getSizeInBits()); - DAG.ComputeMaskedBits(N0.getOperand(0), Mask, KnownZero, KnownOne); + DAG.ComputeMaskedBits(N0.getOperand(0), KnownZero, KnownOne); // If any of the input bits are KnownOne, then the input couldn't be all // zeros, thus the result of the srl will always be zero. @@ -3844,7 +3839,7 @@ SDValue DAGCombiner::visitSRL(SDNode *N) { // If all of the bits input the to ctlz node are known to be zero, then // the result of the ctlz is "32" and the result of the shift is one. - APInt UnknownBits = ~KnownZero & Mask; + APInt UnknownBits = ~KnownZero; if (UnknownBits == 0) return DAG.getConstant(1, VT); // Otherwise, check to see if there is exactly one bit input to the ctlz. @@ -4439,8 +4434,8 @@ SDValue DAGCombiner::visitZERO_EXTEND(SDNode *N) { std::min(Op.getValueSizeInBits(), VT.getSizeInBits())); APInt KnownZero, KnownOne; - DAG.ComputeMaskedBits(Op, TruncatedBits, KnownZero, KnownOne); - if (TruncatedBits == KnownZero) { + DAG.ComputeMaskedBits(Op, KnownZero, KnownOne); + if (TruncatedBits == (KnownZero & TruncatedBits)) { if (VT.bitsGT(Op.getValueType())) return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, Op); if (VT.bitsLT(Op.getValueType())) |

