bool DAGCombiner::SimplifyDemandedBits(SDValue Op, const APInt &Demanded) {
TargetLowering::TargetLoweringOpt TLO(DAG, LegalTypes, LegalOperations);
APInt KnownZero, KnownOne;
+
+ // XXX-disabled:
+ auto Opcode = Op.getOpcode();
+ if (Opcode == ISD::AND || Opcode == ISD::OR) {
+ auto* Op1 = Op.getOperand(0).getNode();
+ auto* Op2 = Op.getOperand(1).getNode();
+ auto* Op1C = dyn_cast<ConstantSDNode>(Op1);
+ auto* Op2C = dyn_cast<ConstantSDNode>(Op2);
+
+ // and X, 0
+ if (Opcode == ISD::AND && !Op1C && Op2C && Op2C->isNullValue()) {
+ return false;
+ }
+
+ // or (and X, 0), Y
+ if (Opcode == ISD::OR) {
+ if (Op1->getOpcode() == ISD::AND) {
+ auto* Op11 = Op1->getOperand(0).getNode();
+ auto* Op12 = Op1->getOperand(1).getNode();
+ auto* Op11C = dyn_cast<ConstantSDNode>(Op11);
+ auto* Op12C = dyn_cast<ConstantSDNode>(Op12);
+ if (!Op11C && Op12C && Op12C->isNullValue()) {
+ return false;
+ }
+ }
+ if (Op1->getOpcode() == ISD::TRUNCATE) {
+ // or (trunc (and %0, 0)), Y
+ auto* Op11 = Op1->getOperand(0).getNode();
+ if (Op11->getOpcode() == ISD::AND) {
+ auto* Op111 = Op11->getOperand(0).getNode();
+ auto* Op112 = Op11->getOperand(1).getNode();
+ auto* Op111C = dyn_cast<ConstantSDNode>(Op111);
+ auto* Op112C = dyn_cast<ConstantSDNode>(Op112);
+ if (!Op111C && Op112C && Op112C->isNullValue()) {
+ // or (and X, 0), Y
+ return false;
+ }
+ }
+ }
+ }
+ }
+
+ // trunc (and X, 0)
+ if (Opcode == ISD::TRUNCATE) {
+ auto* Op1 = Op.getOperand(0).getNode();
+ if (Op1->getOpcode() == ISD::AND) {
+ auto* Op11 = Op1->getOperand(0).getNode();
+ auto* Op12 = Op1->getOperand(1).getNode();
+ auto* Op11C = dyn_cast<ConstantSDNode>(Op11);
+ auto* Op12C = dyn_cast<ConstantSDNode>(Op12);
+ if (!Op11C && Op12C && Op12C->isNullValue()) {
+ return false;
+ }
+ }
+ }
+
if (!TLI.SimplifyDemandedBits(Op, Demanded, KnownZero, KnownOne, TLO))
return false;
// fold (and c1, c2) -> c1&c2
ConstantSDNode *N0C = getAsNonOpaqueConstant(N0);
ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
+
+ // XXX-disabled: (and x, 0) should not be folded.
+ if (!N0C && N1C->isNullValue()) {
+ return SDValue();
+ }
+
if (N0C && N1C && !N1C->isOpaque())
return DAG.FoldConstantArithmetic(ISD::AND, SDLoc(N), VT, N0C, N1C);
// canonicalize constant to RHS
uint64_t PtrOff = ShAmt / 8;
unsigned NewAlign = MinAlign(LN0->getAlignment(), PtrOff);
SDLoc DL(LN0);
+ // The original load itself didn't wrap, so an offset within it doesn't.
+ SDNodeFlags Flags;
+ Flags.setNoUnsignedWrap(true);
SDValue NewPtr = DAG.getNode(ISD::ADD, DL,
PtrType, LN0->getBasePtr(),
- DAG.getConstant(PtrOff, DL, PtrType));
+ DAG.getConstant(PtrOff, DL, PtrType),
+ &Flags);
AddToWorklist(NewPtr.getNode());
SDValue Load;
// fold (bitcast (fneg x)) ->
// flipbit = signbit
// (xor (bitcast x) (build_pair flipbit, flipbit))
+ //
// fold (bitcast (fabs x)) ->
// flipbit = (and (extract_element (bitcast x), 0), signbit)
// (xor (bitcast x) (build_pair flipbit, flipbit))
ZeroCmp, Zero, RV);
}
+/// copysign(x, fp_extend(y)) -> copysign(x, y)
+/// copysign(x, fp_round(y)) -> copysign(x, y)
static inline bool CanCombineFCOPYSIGN_EXTEND_ROUND(SDNode *N) {
- // copysign(x, fp_extend(y)) -> copysign(x, y)
- // copysign(x, fp_round(y)) -> copysign(x, y)
- // Do not optimize out type conversion of f128 type yet.
- // For some target like x86_64, configuration is changed
- // to keep one f128 value in one SSE register, but
- // instruction selection cannot handle FCOPYSIGN on
- // SSE registers yet.
SDValue N1 = N->getOperand(1);
- EVT N1VT = N1->getValueType(0);
- EVT N1Op0VT = N1->getOperand(0)->getValueType(0);
- return (N1.getOpcode() == ISD::FP_EXTEND ||
- N1.getOpcode() == ISD::FP_ROUND) &&
- (N1VT == N1Op0VT || N1Op0VT != MVT::f128);
+ if ((N1.getOpcode() == ISD::FP_EXTEND ||
+ N1.getOpcode() == ISD::FP_ROUND)) {
+ // Do not optimize out type conversion of f128 type yet.
+ // For some targets like x86_64, configuration is changed to keep one f128
+ // value in one SSE register, but instruction selection cannot handle
+ // FCOPYSIGN on SSE registers yet.
+ EVT N1VT = N1->getValueType(0);
+ EVT N1Op0VT = N1->getOperand(0)->getValueType(0);
+ return (N1VT == N1Op0VT || N1Op0VT != MVT::f128);
+ }
+ return false;
}
SDValue DAGCombiner::visitFCOPYSIGN(SDNode *N) {