diff options
Diffstat (limited to 'llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 228 |
1 files changed, 129 insertions, 99 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index f81da723e69..c77c1e08c27 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -348,10 +348,12 @@ namespace { SDValue BuildSDIV(SDNode *N); SDValue BuildSDIVPow2(SDNode *N); SDValue BuildUDIV(SDNode *N); - SDValue BuildReciprocalEstimate(SDValue Op); - SDValue BuildRsqrtEstimate(SDValue Op); - SDValue BuildRsqrtNROneConst(SDValue Op, SDValue Est, unsigned Iterations); - SDValue BuildRsqrtNRTwoConst(SDValue Op, SDValue Est, unsigned Iterations); + SDValue BuildReciprocalEstimate(SDValue Op, SDNodeFlags *Flags); + SDValue BuildRsqrtEstimate(SDValue Op, SDNodeFlags *Flags); + SDValue BuildRsqrtNROneConst(SDValue Op, SDValue Est, unsigned Iterations, + SDNodeFlags *Flags); + SDValue BuildRsqrtNRTwoConst(SDValue Op, SDValue Est, unsigned Iterations, + SDNodeFlags *Flags); SDValue MatchBSwapHWordLow(SDNode *N, SDValue N0, SDValue N1, bool DemandHighBits = true); SDValue MatchBSwapHWord(SDNode *N, SDValue N0, SDValue N1); @@ -614,6 +616,9 @@ static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG, assert(Op.hasOneUse() && "Unknown reuse!"); assert(Depth <= 6 && "GetNegatedExpression doesn't match isNegatibleForFree"); + + const SDNodeFlags *Flags = Op.getNode()->getFlags(); + switch (Op.getOpcode()) { default: llvm_unreachable("Unknown code"); case ISD::ConstantFP: { @@ -631,12 +636,12 @@ static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG, return DAG.getNode(ISD::FSUB, SDLoc(Op), Op.getValueType(), GetNegatedExpression(Op.getOperand(0), DAG, LegalOperations, Depth+1), - Op.getOperand(1)); + Op.getOperand(1), Flags); // fold (fneg (fadd A, B)) -> (fsub (fneg B), A) return DAG.getNode(ISD::FSUB, SDLoc(Op), Op.getValueType(), GetNegatedExpression(Op.getOperand(1), DAG, LegalOperations, Depth+1), - Op.getOperand(0)); + Op.getOperand(0), Flags); case ISD::FSUB: // We can't turn -(A-B) into B-A when we honor signed zeros. assert(Options.UnsafeFPMath); @@ -648,7 +653,7 @@ static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG, // fold (fneg (fsub A, B)) -> (fsub B, A) return DAG.getNode(ISD::FSUB, SDLoc(Op), Op.getValueType(), - Op.getOperand(1), Op.getOperand(0)); + Op.getOperand(1), Op.getOperand(0), Flags); case ISD::FMUL: case ISD::FDIV: @@ -660,13 +665,13 @@ static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG, return DAG.getNode(Op.getOpcode(), SDLoc(Op), Op.getValueType(), GetNegatedExpression(Op.getOperand(0), DAG, LegalOperations, Depth+1), - Op.getOperand(1)); + Op.getOperand(1), Flags); // fold (fneg (fmul X, Y)) -> (fmul X, (fneg Y)) return DAG.getNode(Op.getOpcode(), SDLoc(Op), Op.getValueType(), Op.getOperand(0), GetNegatedExpression(Op.getOperand(1), DAG, - LegalOperations, Depth+1)); + LegalOperations, Depth+1), Flags); case ISD::FP_EXTEND: case ISD::FSIN: @@ -1482,13 +1487,8 @@ SDValue DAGCombiner::combine(SDNode *N) { // Constant operands are canonicalized to RHS. if (isa<ConstantSDNode>(N0) || !isa<ConstantSDNode>(N1)) { SDValue Ops[] = {N1, N0}; - SDNode *CSENode; - if (const auto *BinNode = dyn_cast<BinaryWithFlagsSDNode>(N)) { - CSENode = DAG.getNodeIfExists(N->getOpcode(), N->getVTList(), Ops, - &BinNode->Flags); - } else { - CSENode = DAG.getNodeIfExists(N->getOpcode(), N->getVTList(), Ops); - } + SDNode *CSENode = DAG.getNodeIfExists(N->getOpcode(), N->getVTList(), Ops, + N->getFlags()); if (CSENode) return SDValue(CSENode, 0); } @@ -7931,6 +7931,7 @@ SDValue DAGCombiner::visitFADD(SDNode *N) { EVT VT = N->getValueType(0); SDLoc DL(N); const TargetOptions &Options = DAG.getTarget().Options; + const SDNodeFlags *Flags = &cast<BinaryWithFlagsSDNode>(N)->Flags; // fold vector ops if (VT.isVector()) @@ -7939,23 +7940,23 @@ SDValue DAGCombiner::visitFADD(SDNode *N) { // fold (fadd c1, c2) -> c1 + c2 if (N0CFP && N1CFP) - return DAG.getNode(ISD::FADD, DL, VT, N0, N1); + return DAG.getNode(ISD::FADD, DL, VT, N0, N1, Flags); // canonicalize constant to RHS if (N0CFP && !N1CFP) - return DAG.getNode(ISD::FADD, DL, VT, N1, N0); + return DAG.getNode(ISD::FADD, DL, VT, N1, N0, Flags); // fold (fadd A, (fneg B)) -> (fsub A, B) if ((!LegalOperations || TLI.isOperationLegalOrCustom(ISD::FSUB, VT)) && isNegatibleForFree(N1, LegalOperations, TLI, &Options) == 2) return DAG.getNode(ISD::FSUB, DL, VT, N0, - GetNegatedExpression(N1, DAG, LegalOperations)); + GetNegatedExpression(N1, DAG, LegalOperations), Flags); // fold (fadd (fneg A), B) -> (fsub B, A) if ((!LegalOperations || TLI.isOperationLegalOrCustom(ISD::FSUB, VT)) && isNegatibleForFree(N0, LegalOperations, TLI, &Options) == 2) return DAG.getNode(ISD::FSUB, DL, VT, N1, - GetNegatedExpression(N0, DAG, LegalOperations)); + GetNegatedExpression(N0, DAG, LegalOperations), Flags); // If 'unsafe math' is enabled, fold lots of things. if (Options.UnsafeFPMath) { @@ -7971,7 +7972,9 @@ SDValue DAGCombiner::visitFADD(SDNode *N) { if (N1CFP && N0.getOpcode() == ISD::FADD && N0.getNode()->hasOneUse() && isa<ConstantFPSDNode>(N0.getOperand(1))) return DAG.getNode(ISD::FADD, DL, VT, N0.getOperand(0), - DAG.getNode(ISD::FADD, DL, VT, N0.getOperand(1), N1)); + DAG.getNode(ISD::FADD, DL, VT, N0.getOperand(1), N1, + Flags), + Flags); // If allowed, fold (fadd (fneg x), x) -> 0.0 if (AllowNewConst && N0.getOpcode() == ISD::FNEG && N0.getOperand(0) == N1) @@ -7992,8 +7995,8 @@ SDValue DAGCombiner::visitFADD(SDNode *N) { // (fadd (fmul x, c), x) -> (fmul x, c+1) if (CFP01 && !CFP00 && N0.getOperand(0) == N1) { SDValue NewCFP = DAG.getNode(ISD::FADD, DL, VT, SDValue(CFP01, 0), - DAG.getConstantFP(1.0, DL, VT)); - return DAG.getNode(ISD::FMUL, DL, VT, N1, NewCFP); + DAG.getConstantFP(1.0, DL, VT), Flags); + return DAG.getNode(ISD::FMUL, DL, VT, N1, NewCFP, Flags); } // (fadd (fmul x, c), (fadd x, x)) -> (fmul x, c+2) @@ -8001,8 +8004,8 @@ SDValue DAGCombiner::visitFADD(SDNode *N) { N1.getOperand(0) == N1.getOperand(1) && N0.getOperand(0) == N1.getOperand(0)) { SDValue NewCFP = DAG.getNode(ISD::FADD, DL, VT, SDValue(CFP01, 0), - DAG.getConstantFP(2.0, DL, VT)); - return DAG.getNode(ISD::FMUL, DL, VT, N0.getOperand(0), NewCFP); + DAG.getConstantFP(2.0, DL, VT), Flags); + return DAG.getNode(ISD::FMUL, DL, VT, N0.getOperand(0), NewCFP, Flags); } } @@ -8013,8 +8016,8 @@ SDValue DAGCombiner::visitFADD(SDNode *N) { // (fadd x, (fmul x, c)) -> (fmul x, c+1) if (CFP11 && !CFP10 && N1.getOperand(0) == N0) { SDValue NewCFP = DAG.getNode(ISD::FADD, DL, VT, SDValue(CFP11, 0), - DAG.getConstantFP(1.0, DL, VT)); - return DAG.getNode(ISD::FMUL, DL, VT, N0, NewCFP); + DAG.getConstantFP(1.0, DL, VT), Flags); + return DAG.getNode(ISD::FMUL, DL, VT, N0, NewCFP, Flags); } // (fadd (fadd x, x), (fmul x, c)) -> (fmul x, c+2) @@ -8022,8 +8025,8 @@ SDValue DAGCombiner::visitFADD(SDNode *N) { N0.getOperand(0) == N0.getOperand(1) && N1.getOperand(0) == N0.getOperand(0)) { SDValue NewCFP = DAG.getNode(ISD::FADD, DL, VT, SDValue(CFP11, 0), - DAG.getConstantFP(2.0, DL, VT)); - return DAG.getNode(ISD::FMUL, DL, VT, N1.getOperand(0), NewCFP); + DAG.getConstantFP(2.0, DL, VT), Flags); + return DAG.getNode(ISD::FMUL, DL, VT, N1.getOperand(0), NewCFP, Flags); } } @@ -8033,7 +8036,7 @@ SDValue DAGCombiner::visitFADD(SDNode *N) { if (!CFP && N0.getOperand(0) == N0.getOperand(1) && (N0.getOperand(0) == N1)) { return DAG.getNode(ISD::FMUL, DL, VT, - N1, DAG.getConstantFP(3.0, DL, VT)); + N1, DAG.getConstantFP(3.0, DL, VT), Flags); } } @@ -8043,7 +8046,7 @@ SDValue DAGCombiner::visitFADD(SDNode *N) { if (!CFP10 && N1.getOperand(0) == N1.getOperand(1) && N1.getOperand(0) == N0) { return DAG.getNode(ISD::FMUL, DL, VT, - N0, DAG.getConstantFP(3.0, DL, VT)); + N0, DAG.getConstantFP(3.0, DL, VT), Flags); } } @@ -8053,8 +8056,8 @@ SDValue DAGCombiner::visitFADD(SDNode *N) { N0.getOperand(0) == N0.getOperand(1) && N1.getOperand(0) == N1.getOperand(1) && N0.getOperand(0) == N1.getOperand(0)) { - return DAG.getNode(ISD::FMUL, DL, VT, - N0.getOperand(0), DAG.getConstantFP(4.0, DL, VT)); + return DAG.getNode(ISD::FMUL, DL, VT, N0.getOperand(0), + DAG.getConstantFP(4.0, DL, VT), Flags); } } } // enable-unsafe-fp-math @@ -8076,6 +8079,7 @@ SDValue DAGCombiner::visitFSUB(SDNode *N) { EVT VT = N->getValueType(0); SDLoc dl(N); const TargetOptions &Options = DAG.getTarget().Options; + const SDNodeFlags *Flags = &cast<BinaryWithFlagsSDNode>(N)->Flags; // fold vector ops if (VT.isVector()) @@ -8084,12 +8088,12 @@ SDValue DAGCombiner::visitFSUB(SDNode *N) { // fold (fsub c1, c2) -> c1-c2 if (N0CFP && N1CFP) - return DAG.getNode(ISD::FSUB, dl, VT, N0, N1); + return DAG.getNode(ISD::FSUB, dl, VT, N0, N1, Flags); // fold (fsub A, (fneg B)) -> (fadd A, B) if (isNegatibleForFree(N1, LegalOperations, TLI, &Options)) return DAG.getNode(ISD::FADD, dl, VT, N0, - GetNegatedExpression(N1, DAG, LegalOperations)); + GetNegatedExpression(N1, DAG, LegalOperations), Flags); // If 'unsafe math' is enabled, fold lots of things. if (Options.UnsafeFPMath) { @@ -8140,6 +8144,7 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) { EVT VT = N->getValueType(0); SDLoc DL(N); const TargetOptions &Options = DAG.getTarget().Options; + const SDNodeFlags *Flags = &cast<BinaryWithFlagsSDNode>(N)->Flags; // fold vector ops if (VT.isVector()) { @@ -8150,12 +8155,12 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) { // fold (fmul c1, c2) -> c1*c2 if (N0CFP && N1CFP) - return DAG.getNode(ISD::FMUL, DL, VT, N0, N1); + return DAG.getNode(ISD::FMUL, DL, VT, N0, N1, Flags); // canonicalize constant to RHS if (isConstantFPBuildVectorOrConstantFP(N0) && !isConstantFPBuildVectorOrConstantFP(N1)) - return DAG.getNode(ISD::FMUL, DL, VT, N1, N0); + return DAG.getNode(ISD::FMUL, DL, VT, N1, N0, Flags); // fold (fmul A, 1.0) -> A if (N1CFP && N1CFP->isExactlyValue(1.0)) @@ -8184,8 +8189,8 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) { // the second operand of the outer multiply are constants. if ((N1CFP && isConstOrConstSplatFP(N01)) || (BV1 && BV01 && BV1->isConstant() && BV01->isConstant())) { - SDValue MulConsts = DAG.getNode(ISD::FMUL, DL, VT, N01, N1); - return DAG.getNode(ISD::FMUL, DL, VT, N00, MulConsts); + SDValue MulConsts = DAG.getNode(ISD::FMUL, DL, VT, N01, N1, Flags); + return DAG.getNode(ISD::FMUL, DL, VT, N00, MulConsts, Flags); } } } @@ -8198,14 +8203,14 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) { (N0.getOperand(0) == N0.getOperand(1)) && N0.hasOneUse()) { const SDValue Two = DAG.getConstantFP(2.0, DL, VT); - SDValue MulConsts = DAG.getNode(ISD::FMUL, DL, VT, Two, N1); - return DAG.getNode(ISD::FMUL, DL, VT, N0.getOperand(0), MulConsts); + SDValue MulConsts = DAG.getNode(ISD::FMUL, DL, VT, Two, N1, Flags); + return DAG.getNode(ISD::FMUL, DL, VT, N0.getOperand(0), MulConsts, Flags); } } // fold (fmul X, 2.0) -> (fadd X, X) if (N1CFP && N1CFP->isExactlyValue(+2.0)) - return DAG.getNode(ISD::FADD, DL, VT, N0, N0); + return DAG.getNode(ISD::FADD, DL, VT, N0, N0, Flags); // fold (fmul X, -1.0) -> (fneg X) if (N1CFP && N1CFP->isExactlyValue(-1.0)) @@ -8220,7 +8225,8 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) { if (LHSNeg == 2 || RHSNeg == 2) return DAG.getNode(ISD::FMUL, DL, VT, GetNegatedExpression(N0, DAG, LegalOperations), - GetNegatedExpression(N1, DAG, LegalOperations)); + GetNegatedExpression(N1, DAG, LegalOperations), + Flags); } } @@ -8250,6 +8256,7 @@ SDValue DAGCombiner::visitFMA(SDNode *N) { if (N1CFP && N1CFP->isZero()) return N2; } + // TODO: The FMA node should have flags that propagate to these nodes. if (N0CFP && N0CFP->isExactlyValue(1.0)) return DAG.getNode(ISD::FADD, SDLoc(N), VT, N1, N2); if (N1CFP && N1CFP->isExactlyValue(1.0)) @@ -8259,13 +8266,19 @@ SDValue DAGCombiner::visitFMA(SDNode *N) { if (N0CFP && !N1CFP) return DAG.getNode(ISD::FMA, SDLoc(N), VT, N1, N0, N2); + // TODO: FMA nodes should have flags that propagate to the created nodes. + // For now, create a Flags object for use with all unsafe math transforms. + SDNodeFlags Flags; + Flags.setUnsafeAlgebra(true); + // (fma x, c1, (fmul x, c2)) -> (fmul x, c1+c2) if (Options.UnsafeFPMath && N1CFP && N2.getOpcode() == ISD::FMUL && N0 == N2.getOperand(0) && N2.getOperand(1).getOpcode() == ISD::ConstantFP) { return DAG.getNode(ISD::FMUL, dl, VT, N0, - DAG.getNode(ISD::FADD, dl, VT, N1, N2.getOperand(1))); + DAG.getNode(ISD::FADD, dl, VT, N1, N2.getOperand(1), + &Flags), &Flags); } @@ -8275,7 +8288,8 @@ SDValue DAGCombiner::visitFMA(SDNode *N) { N0.getOperand(1).getOpcode() == ISD::ConstantFP) { return DAG.getNode(ISD::FMA, dl, VT, N0.getOperand(0), - DAG.getNode(ISD::FMUL, dl, VT, N1, N0.getOperand(1)), + DAG.getNode(ISD::FMUL, dl, VT, N1, N0.getOperand(1), + &Flags), N2); } @@ -8283,29 +8297,33 @@ SDValue DAGCombiner::visitFMA(SDNode *N) { // (fma x, -1, y) -> (fadd (fneg x), y) if (N1CFP) { if (N1CFP->isExactlyValue(1.0)) + // TODO: The FMA node should have flags that propagate to this node. return DAG.getNode(ISD::FADD, dl, VT, N0, N2); if (N1CFP->isExactlyValue(-1.0) && (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT))) { SDValue RHSNeg = DAG.getNode(ISD::FNEG, dl, VT, N0); AddToWorklist(RHSNeg.getNode()); + // TODO: The FMA node should have flags that propagate to this node. return DAG.getNode(ISD::FADD, dl, VT, N2, RHSNeg); } } // (fma x, c, x) -> (fmul x, (c+1)) - if (Options.UnsafeFPMath && N1CFP && N0 == N2) + if (Options.UnsafeFPMath && N1CFP && N0 == N2) { return DAG.getNode(ISD::FMUL, dl, VT, N0, DAG.getNode(ISD::FADD, dl, VT, - N1, DAG.getConstantFP(1.0, dl, VT))); - + N1, DAG.getConstantFP(1.0, dl, VT), + &Flags), &Flags); + } // (fma x, c, (fneg x)) -> (fmul x, (c-1)) if (Options.UnsafeFPMath && N1CFP && - N2.getOpcode() == ISD::FNEG && N2.getOperand(0) == N0) + N2.getOpcode() == ISD::FNEG && N2.getOperand(0) == N0) { return DAG.getNode(ISD::FMUL, dl, VT, N0, DAG.getNode(ISD::FADD, dl, VT, - N1, DAG.getConstantFP(-1.0, dl, VT))); - + N1, DAG.getConstantFP(-1.0, dl, VT), + &Flags), &Flags); + } return SDValue(); } @@ -8349,17 +8367,15 @@ SDValue DAGCombiner::combineRepeatedFPDivisors(SDNode *N) { EVT VT = N->getValueType(0); SDLoc DL(N); SDValue FPOne = DAG.getConstantFP(1.0, DL, VT); - // FIXME: This optimization requires some level of fast-math, so the - // created reciprocal node should at least have the 'allowReciprocal' - // fast-math-flag set. - SDValue Reciprocal = DAG.getNode(ISD::FDIV, DL, VT, FPOne, N1); + const SDNodeFlags *Flags = &cast<BinaryWithFlagsSDNode>(N)->Flags; + SDValue Reciprocal = DAG.getNode(ISD::FDIV, DL, VT, FPOne, N1, Flags); // Dividend / Divisor -> Dividend * Reciprocal for (auto *U : Users) { SDValue Dividend = U->getOperand(0); if (Dividend != FPOne) { SDValue NewNode = DAG.getNode(ISD::FMUL, SDLoc(U), VT, Dividend, - Reciprocal); + Reciprocal, Flags); CombineTo(U, NewNode); } else if (U != Reciprocal.getNode()) { // In the absence of fast-math-flags, this user node is always the @@ -8378,6 +8394,7 @@ SDValue DAGCombiner::visitFDIV(SDNode *N) { EVT VT = N->getValueType(0); SDLoc DL(N); const TargetOptions &Options = DAG.getTarget().Options; + SDNodeFlags *Flags = &cast<BinaryWithFlagsSDNode>(N)->Flags; // fold vector ops if (VT.isVector()) @@ -8386,7 +8403,7 @@ SDValue DAGCombiner::visitFDIV(SDNode *N) { // fold (fdiv c1, c2) -> c1/c2 if (N0CFP && N1CFP) - return DAG.getNode(ISD::FDIV, SDLoc(N), VT, N0, N1); + return DAG.getNode(ISD::FDIV, SDLoc(N), VT, N0, N1, Flags); if (Options.UnsafeFPMath) { // fold (fdiv X, c2) -> fmul X, 1/c2 if losing precision is acceptable. @@ -8405,28 +8422,30 @@ SDValue DAGCombiner::visitFDIV(SDNode *N) { TLI.isOperationLegal(llvm::ISD::ConstantFP, VT) || TLI.isFPImmLegal(Recip, VT))) return DAG.getNode(ISD::FMUL, DL, VT, N0, - DAG.getConstantFP(Recip, DL, VT)); + DAG.getConstantFP(Recip, DL, VT), Flags); } // If this FDIV is part of a reciprocal square root, it may be folded // into a target-specific square root estimate instruction. if (N1.getOpcode() == ISD::FSQRT) { - if (SDValue RV = BuildRsqrtEstimate(N1.getOperand(0))) { - return DAG.getNode(ISD::FMUL, DL, VT, N0, RV); + if (SDValue RV = BuildRsqrtEstimate(N1.getOperand(0), Flags)) { + return DAG.getNode(ISD::FMUL, DL, VT, N0, RV, Flags); } } else if (N1.getOpcode() == ISD::FP_EXTEND && N1.getOperand(0).getOpcode() == ISD::FSQRT) { - if (SDValue RV = BuildRsqrtEstimate(N1.getOperand(0).getOperand(0))) { + if (SDValue RV = BuildRsqrtEstimate(N1.getOperand(0).getOperand(0), + Flags)) { RV = DAG.getNode(ISD::FP_EXTEND, SDLoc(N1), VT, RV); AddToWorklist(RV.getNode()); - return DAG.getNode(ISD::FMUL, DL, VT, N0, RV); + return DAG.getNode(ISD::FMUL, DL, VT, N0, RV, Flags); } } else if (N1.getOpcode() == ISD::FP_ROUND && N1.getOperand(0).getOpcode() == ISD::FSQRT) { - if (SDValue RV = BuildRsqrtEstimate(N1.getOperand(0).getOperand(0))) { + if (SDValue RV = BuildRsqrtEstimate(N1.getOperand(0).getOperand(0), + Flags)) { RV = DAG.getNode(ISD::FP_ROUND, SDLoc(N1), VT, RV, N1.getOperand(1)); AddToWorklist(RV.getNode()); - return DAG.getNode(ISD::FMUL, DL, VT, N0, RV); + return DAG.getNode(ISD::FMUL, DL, VT, N0, RV, Flags); } } else if (N1.getOpcode() == ISD::FMUL) { // Look through an FMUL. Even though this won't remove the FDIV directly, @@ -8443,18 +8462,18 @@ SDValue DAGCombiner::visitFDIV(SDNode *N) { if (SqrtOp.getNode()) { // We found a FSQRT, so try to make this fold: // x / (y * sqrt(z)) -> x * (rsqrt(z) / y) - if (SDValue RV = BuildRsqrtEstimate(SqrtOp.getOperand(0))) { - RV = DAG.getNode(ISD::FDIV, SDLoc(N1), VT, RV, OtherOp); + if (SDValue RV = BuildRsqrtEstimate(SqrtOp.getOperand(0), Flags)) { + RV = DAG.getNode(ISD::FDIV, SDLoc(N1), VT, RV, OtherOp, Flags); AddToWorklist(RV.getNode()); - return DAG.getNode(ISD::FMUL, DL, VT, N0, RV); + return DAG.getNode(ISD::FMUL, DL, VT, N0, RV, Flags); } } } // Fold into a reciprocal estimate and multiply instead of a real divide. - if (SDValue RV = BuildReciprocalEstimate(N1)) { + if (SDValue RV = BuildReciprocalEstimate(N1, Flags)) { AddToWorklist(RV.getNode()); - return DAG.getNode(ISD::FMUL, DL, VT, N0, RV); + return DAG.getNode(ISD::FMUL, DL, VT, N0, RV, Flags); } } @@ -8466,7 +8485,8 @@ SDValue DAGCombiner::visitFDIV(SDNode *N) { if (LHSNeg == 2 || RHSNeg == 2) return DAG.getNode(ISD::FDIV, SDLoc(N), VT, GetNegatedExpression(N0, DAG, LegalOperations), - GetNegatedExpression(N1, DAG, LegalOperations)); + GetNegatedExpression(N1, DAG, LegalOperations), + Flags); } } @@ -8485,7 +8505,8 @@ SDValue DAGCombiner::visitFREM(SDNode *N) { // fold (frem c1, c2) -> fmod(c1,c2) if (N0CFP && N1CFP) - return DAG.getNode(ISD::FREM, SDLoc(N), VT, N0, N1); + return DAG.getNode(ISD::FREM, SDLoc(N), VT, N0, N1, + &cast<BinaryWithFlagsSDNode>(N)->Flags); return SDValue(); } @@ -8494,14 +8515,19 @@ SDValue DAGCombiner::visitFSQRT(SDNode *N) { if (!DAG.getTarget().Options.UnsafeFPMath || TLI.isFsqrtCheap()) return SDValue(); + // TODO: FSQRT nodes should have flags that propagate to the created nodes. + // For now, create a Flags object for use with all unsafe math transforms. + SDNodeFlags Flags; + Flags.setUnsafeAlgebra(true); + // Compute this as X * (1/sqrt(X)) = X * (X ** -0.5) - SDValue RV = BuildRsqrtEstimate(N->getOperand(0)); + SDValue RV = BuildRsqrtEstimate(N->getOperand(0), &Flags); if (!RV) return SDValue(); EVT VT = RV.getValueType(); SDLoc DL(N); - RV = DAG.getNode(ISD::FMUL, DL, VT, N->getOperand(0), RV); + RV = DAG.getNode(ISD::FMUL, DL, VT, N->getOperand(0), RV, &Flags); AddToWorklist(RV.getNode()); // Unfortunately, RV is now NaN if the input was exactly 0. @@ -8916,9 +8942,10 @@ SDValue DAGCombiner::visitFNEG(SDNode *N) { if (Level >= AfterLegalizeDAG && (TLI.isFPImmLegal(CVal, N->getValueType(0)) || TLI.isOperationLegal(ISD::ConstantFP, N->getValueType(0)))) - return DAG.getNode( - ISD::FMUL, SDLoc(N), VT, N0.getOperand(0), - DAG.getNode(ISD::FNEG, SDLoc(N), VT, N0.getOperand(1))); + return DAG.getNode(ISD::FMUL, SDLoc(N), VT, N0.getOperand(0), + DAG.getNode(ISD::FNEG, SDLoc(N), VT, + N0.getOperand(1)), + &cast<BinaryWithFlagsSDNode>(N0)->Flags); } } @@ -13346,7 +13373,7 @@ SDValue DAGCombiner::SimplifyVBinOp(SDNode *N) { } SDValue FoldOp = DAG.getNode(N->getOpcode(), SDLoc(LHS), VT, - LHSOp, RHSOp); + LHSOp, RHSOp, N->getFlags()); // We need the resulting constant to be legal if we are in a phase after // legalization, so zero extend to the smallest operand type if required. @@ -13383,7 +13410,8 @@ SDValue DAGCombiner::SimplifyVBinOp(SDNode *N) { EVT VT = N->getValueType(0); SDValue UndefVector = LHS.getOperand(1); SDValue NewBinOp = DAG.getNode(N->getOpcode(), SDLoc(N), VT, - LHS.getOperand(0), RHS.getOperand(0)); + LHS.getOperand(0), RHS.getOperand(0), + N->getFlags()); AddUsersToWorklist(N); return DAG.getVectorShuffle(VT, SDLoc(N), NewBinOp, UndefVector, &SVN0->getMask()[0]); @@ -13895,7 +13923,7 @@ SDValue DAGCombiner::BuildUDIV(SDNode *N) { return S; } -SDValue DAGCombiner::BuildReciprocalEstimate(SDValue Op) { +SDValue DAGCombiner::BuildReciprocalEstimate(SDValue Op, SDNodeFlags *Flags) { if (Level >= AfterLegalizeDAG) return SDValue(); @@ -13919,16 +13947,16 @@ SDValue DAGCombiner::BuildReciprocalEstimate(SDValue Op) { // Newton iterations: Est = Est + Est (1 - Arg * Est) for (unsigned i = 0; i < Iterations; ++i) { - SDValue NewEst = DAG.getNode(ISD::FMUL, DL, VT, Op, Est); + SDValue NewEst = DAG.getNode(ISD::FMUL, DL, VT, Op, Est, Flags); AddToWorklist(NewEst.getNode()); - NewEst = DAG.getNode(ISD::FSUB, DL, VT, FPOne, NewEst); + NewEst = DAG.getNode(ISD::FSUB, DL, VT, FPOne, NewEst, Flags); AddToWorklist(NewEst.getNode()); - NewEst = DAG.getNode(ISD::FMUL, DL, VT, Est, NewEst); + NewEst = DAG.getNode(ISD::FMUL, DL, VT, Est, NewEst, Flags); AddToWorklist(NewEst.getNode()); - Est = DAG.getNode(ISD::FADD, DL, VT, Est, NewEst); + Est = DAG.getNode(ISD::FADD, DL, VT, Est, NewEst, Flags); AddToWorklist(Est.getNode()); } } @@ -13945,31 +13973,32 @@ SDValue DAGCombiner::BuildReciprocalEstimate(SDValue Op) { /// X_{i+1} = X_i (1.5 - A X_i^2 / 2) /// As a result, we precompute A/2 prior to the iteration loop. SDValue DAGCombiner::BuildRsqrtNROneConst(SDValue Arg, SDValue Est, - unsigned Iterations) { + unsigned Iterations, + SDNodeFlags *Flags) { EVT VT = Arg.getValueType(); SDLoc DL(Arg); SDValue ThreeHalves = DAG.getConstantFP(1.5, DL, VT); // We now need 0.5 * Arg which we can write as (1.5 * Arg - Arg) so that // this entire sequence requires only one FP constant. - SDValue HalfArg = DAG.getNode(ISD::FMUL, DL, VT, ThreeHalves, Arg); + SDValue HalfArg = DAG.getNode(ISD::FMUL, DL, VT, ThreeHalves, Arg, Flags); AddToWorklist(HalfArg.getNode()); - HalfArg = DAG.getNode(ISD::FSUB, DL, VT, HalfArg, Arg); + HalfArg = DAG.getNode(ISD::FSUB, DL, VT, HalfArg, Arg, Flags); AddToWorklist(HalfArg.getNode()); // Newton iterations: Est = Est * (1.5 - HalfArg * Est * Est) for (unsigned i = 0; i < Iterations; ++i) { - SDValue NewEst = DAG.getNode(ISD::FMUL, DL, VT, Est, Est); + SDValue NewEst = DAG.getNode(ISD::FMUL, DL, VT, Est, Est, Flags); AddToWorklist(NewEst.getNode()); - NewEst = DAG.getNode(ISD::FMUL, DL, VT, HalfArg, NewEst); + NewEst = DAG.getNode(ISD::FMUL, DL, VT, HalfArg, NewEst, Flags); AddToWorklist(NewEst.getNode()); - NewEst = DAG.getNode(ISD::FSUB, DL, VT, ThreeHalves, NewEst); + NewEst = DAG.getNode(ISD::FSUB, DL, VT, ThreeHalves, NewEst, Flags); AddToWorklist(NewEst.getNode()); - Est = DAG.getNode(ISD::FMUL, DL, VT, Est, NewEst); + Est = DAG.getNode(ISD::FMUL, DL, VT, Est, NewEst, Flags); AddToWorklist(Est.getNode()); } return Est; @@ -13981,7 +14010,8 @@ SDValue DAGCombiner::BuildRsqrtNROneConst(SDValue Arg, SDValue Est, /// => /// X_{i+1} = (-0.5 * X_i) * (A * X_i * X_i + (-3.0)) SDValue DAGCombiner::BuildRsqrtNRTwoConst(SDValue Arg, SDValue Est, - unsigned Iterations) { + unsigned Iterations, + SDNodeFlags *Flags) { EVT VT = Arg.getValueType(); SDLoc DL(Arg); SDValue MinusThree = DAG.getConstantFP(-3.0, DL, VT); @@ -13989,25 +14019,25 @@ SDValue DAGCombiner::BuildRsqrtNRTwoConst(SDValue Arg, SDValue Est, // Newton iterations: Est = -0.5 * Est * (-3.0 + Arg * Est * Est) for (unsigned i = 0; i < Iterations; ++i) { - SDValue HalfEst = DAG.getNode(ISD::FMUL, DL, VT, Est, MinusHalf); + SDValue HalfEst = DAG.getNode(ISD::FMUL, DL, VT, Est, MinusHalf, Flags); AddToWorklist(HalfEst.getNode()); - Est = DAG.getNode(ISD::FMUL, DL, VT, Est, Est); + Est = DAG.getNode(ISD::FMUL, DL, VT, Est, Est, Flags); AddToWorklist(Est.getNode()); - Est = DAG.getNode(ISD::FMUL, DL, VT, Est, Arg); + Est = DAG.getNode(ISD::FMUL, DL, VT, Est, Arg, Flags); AddToWorklist(Est.getNode()); - Est = DAG.getNode(ISD::FADD, DL, VT, Est, MinusThree); + Est = DAG.getNode(ISD::FADD, DL, VT, Est, MinusThree, Flags); AddToWorklist(Est.getNode()); - Est = DAG.getNode(ISD::FMUL, DL, VT, Est, HalfEst); + Est = DAG.getNode(ISD::FMUL, DL, VT, Est, HalfEst, Flags); AddToWorklist(Est.getNode()); } return Est; } -SDValue DAGCombiner::BuildRsqrtEstimate(SDValue Op) { +SDValue DAGCombiner::BuildRsqrtEstimate(SDValue Op, SDNodeFlags *Flags) { if (Level >= AfterLegalizeDAG) return SDValue(); @@ -14019,8 +14049,8 @@ SDValue DAGCombiner::BuildRsqrtEstimate(SDValue Op) { AddToWorklist(Est.getNode()); if (Iterations) { Est = UseOneConstNR ? - BuildRsqrtNROneConst(Op, Est, Iterations) : - BuildRsqrtNRTwoConst(Op, Est, Iterations); + BuildRsqrtNROneConst(Op, Est, Iterations, Flags) : + BuildRsqrtNRTwoConst(Op, Est, Iterations, Flags); } return Est; } |
