diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
-rw-r--r-- | lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 135 |
1 files changed, 91 insertions, 44 deletions
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index d8208a4..80cf0a8 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -180,7 +180,9 @@ namespace { SDValue visitSRA(SDNode *N); SDValue visitSRL(SDNode *N); SDValue visitCTLZ(SDNode *N); + SDValue visitCTLZ_ZERO_UNDEF(SDNode *N); SDValue visitCTTZ(SDNode *N); + SDValue visitCTTZ_ZERO_UNDEF(SDNode *N); SDValue visitCTPOP(SDNode *N); SDValue visitSELECT(SDNode *N); SDValue visitSELECT_CC(SDNode *N); @@ -361,6 +363,7 @@ CommitTargetLoweringOpt(const TargetLowering::TargetLoweringOpt &TLO) { /// specified expression for the same cost as the expression itself, or 2 if we /// can compute the negated form more cheaply than the expression itself. static char isNegatibleForFree(SDValue Op, bool LegalOperations, + const TargetOptions *Options, unsigned Depth = 0) { // No compile time optimizations on this type. if (Op.getValueType() == MVT::ppcf128) @@ -383,34 +386,39 @@ static char isNegatibleForFree(SDValue Op, bool LegalOperations, return LegalOperations ? 0 : 1; case ISD::FADD: // FIXME: determine better conditions for this xform. - if (!UnsafeFPMath) return 0; + if (!Options->UnsafeFPMath) return 0; // fold (fsub (fadd A, B)) -> (fsub (fneg A), B) - if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1)) + if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, Options, + Depth + 1)) return V; // fold (fneg (fadd A, B)) -> (fsub (fneg B), A) - return isNegatibleForFree(Op.getOperand(1), LegalOperations, Depth+1); + return isNegatibleForFree(Op.getOperand(1), LegalOperations, Options, + Depth + 1); case ISD::FSUB: // We can't turn -(A-B) into B-A when we honor signed zeros. - if (!UnsafeFPMath) return 0; + if (!Options->UnsafeFPMath) return 0; // fold (fneg (fsub A, B)) -> (fsub B, A) return 1; case ISD::FMUL: case ISD::FDIV: - if (HonorSignDependentRoundingFPMath()) return 0; + if (Options->HonorSignDependentRoundingFPMath()) return 0; // fold (fneg (fmul X, Y)) -> (fmul (fneg X), Y) or (fmul X, (fneg Y)) - if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1)) + if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, Options, + Depth + 1)) return V; - return isNegatibleForFree(Op.getOperand(1), LegalOperations, Depth+1); + return isNegatibleForFree(Op.getOperand(1), LegalOperations, Options, + Depth + 1); case ISD::FP_EXTEND: case ISD::FP_ROUND: case ISD::FSIN: - return isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1); + return isNegatibleForFree(Op.getOperand(0), LegalOperations, Options, + Depth + 1); } } @@ -434,10 +442,11 @@ static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG, } case ISD::FADD: // FIXME: determine better conditions for this xform. - assert(UnsafeFPMath); + assert(DAG.getTarget().Options.UnsafeFPMath); // fold (fneg (fadd A, B)) -> (fsub (fneg A), B) - if (isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1)) + if (isNegatibleForFree(Op.getOperand(0), LegalOperations, + &DAG.getTarget().Options, Depth+1)) return DAG.getNode(ISD::FSUB, Op.getDebugLoc(), Op.getValueType(), GetNegatedExpression(Op.getOperand(0), DAG, LegalOperations, Depth+1), @@ -449,7 +458,7 @@ static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG, Op.getOperand(0)); case ISD::FSUB: // We can't turn -(A-B) into B-A when we honor signed zeros. - assert(UnsafeFPMath); + assert(DAG.getTarget().Options.UnsafeFPMath); // fold (fneg (fsub 0, B)) -> B if (ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(Op.getOperand(0))) @@ -462,10 +471,11 @@ static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG, case ISD::FMUL: case ISD::FDIV: - assert(!HonorSignDependentRoundingFPMath()); + assert(!DAG.getTarget().Options.HonorSignDependentRoundingFPMath()); // fold (fneg (fmul X, Y)) -> (fmul (fneg X), Y) - if (isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1)) + if (isNegatibleForFree(Op.getOperand(0), LegalOperations, + &DAG.getTarget().Options, Depth+1)) return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), Op.getValueType(), GetNegatedExpression(Op.getOperand(0), DAG, LegalOperations, Depth+1), @@ -1070,7 +1080,9 @@ SDValue DAGCombiner::visit(SDNode *N) { case ISD::SRA: return visitSRA(N); case ISD::SRL: return visitSRL(N); case ISD::CTLZ: return visitCTLZ(N); + case ISD::CTLZ_ZERO_UNDEF: return visitCTLZ_ZERO_UNDEF(N); case ISD::CTTZ: return visitCTTZ(N); + case ISD::CTTZ_ZERO_UNDEF: return visitCTTZ_ZERO_UNDEF(N); case ISD::CTPOP: return visitCTPOP(N); case ISD::SELECT: return visitSELECT(N); case ISD::SELECT_CC: return visitSELECT_CC(N); @@ -1769,7 +1781,7 @@ SDValue DAGCombiner::visitSDIV(SDNode *N) { N0, N1); } // fold (sdiv X, pow2) -> simple ops after legalize - if (N1C && !N1C->isNullValue() && !TLI.isIntDivCheap() && + if (N1C && !N1C->isNullValue() && (N1C->getAPIntValue().isPowerOf2() || (-N1C->getAPIntValue()).isPowerOf2())) { // If dividing by powers of two is cheap, then don't perform the following @@ -3709,6 +3721,16 @@ SDValue DAGCombiner::visitCTLZ(SDNode *N) { return SDValue(); } +SDValue DAGCombiner::visitCTLZ_ZERO_UNDEF(SDNode *N) { + SDValue N0 = N->getOperand(0); + EVT VT = N->getValueType(0); + + // fold (ctlz_zero_undef c1) -> c2 + if (isa<ConstantSDNode>(N0)) + return DAG.getNode(ISD::CTLZ_ZERO_UNDEF, N->getDebugLoc(), VT, N0); + return SDValue(); +} + SDValue DAGCombiner::visitCTTZ(SDNode *N) { SDValue N0 = N->getOperand(0); EVT VT = N->getValueType(0); @@ -3719,6 +3741,16 @@ SDValue DAGCombiner::visitCTTZ(SDNode *N) { return SDValue(); } +SDValue DAGCombiner::visitCTTZ_ZERO_UNDEF(SDNode *N) { + SDValue N0 = N->getOperand(0); + EVT VT = N->getValueType(0); + + // fold (cttz_zero_undef c1) -> c2 + if (isa<ConstantSDNode>(N0)) + return DAG.getNode(ISD::CTTZ_ZERO_UNDEF, N->getDebugLoc(), VT, N0); + return SDValue(); +} + SDValue DAGCombiner::visitCTPOP(SDNode *N) { SDValue N0 = N->getOperand(0); EVT VT = N->getValueType(0); @@ -5254,20 +5286,22 @@ SDValue DAGCombiner::visitFADD(SDNode *N) { if (N0CFP && !N1CFP) return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N1, N0); // fold (fadd A, 0) -> A - if (UnsafeFPMath && N1CFP && N1CFP->getValueAPF().isZero()) + if (DAG.getTarget().Options.UnsafeFPMath && N1CFP && + N1CFP->getValueAPF().isZero()) return N0; // fold (fadd A, (fneg B)) -> (fsub A, B) - if (isNegatibleForFree(N1, LegalOperations) == 2) + if (isNegatibleForFree(N1, LegalOperations, &DAG.getTarget().Options) == 2) return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N0, GetNegatedExpression(N1, DAG, LegalOperations)); // fold (fadd (fneg A), B) -> (fsub B, A) - if (isNegatibleForFree(N0, LegalOperations) == 2) + if (isNegatibleForFree(N0, LegalOperations, &DAG.getTarget().Options) == 2) return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N1, GetNegatedExpression(N0, DAG, LegalOperations)); // If allowed, fold (fadd (fadd x, c1), c2) -> (fadd x, (fadd c1, c2)) - if (UnsafeFPMath && N1CFP && N0.getOpcode() == ISD::FADD && - N0.getNode()->hasOneUse() && isa<ConstantFPSDNode>(N0.getOperand(1))) + if (DAG.getTarget().Options.UnsafeFPMath && N1CFP && + N0.getOpcode() == ISD::FADD && N0.getNode()->hasOneUse() && + isa<ConstantFPSDNode>(N0.getOperand(1))) return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0.getOperand(0), DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0.getOperand(1), N1)); @@ -5292,17 +5326,19 @@ SDValue DAGCombiner::visitFSUB(SDNode *N) { if (N0CFP && N1CFP && VT != MVT::ppcf128) return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N0, N1); // fold (fsub A, 0) -> A - if (UnsafeFPMath && N1CFP && N1CFP->getValueAPF().isZero()) + if (DAG.getTarget().Options.UnsafeFPMath && + N1CFP && N1CFP->getValueAPF().isZero()) return N0; // fold (fsub 0, B) -> -B - if (UnsafeFPMath && N0CFP && N0CFP->getValueAPF().isZero()) { - if (isNegatibleForFree(N1, LegalOperations)) + if (DAG.getTarget().Options.UnsafeFPMath && + N0CFP && N0CFP->getValueAPF().isZero()) { + if (isNegatibleForFree(N1, LegalOperations, &DAG.getTarget().Options)) return GetNegatedExpression(N1, DAG, LegalOperations); if (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT)) return DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT, N1); } // fold (fsub A, (fneg B)) -> (fadd A, B) - if (isNegatibleForFree(N1, LegalOperations)) + if (isNegatibleForFree(N1, LegalOperations, &DAG.getTarget().Options)) return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0, GetNegatedExpression(N1, DAG, LegalOperations)); @@ -5329,10 +5365,12 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) { if (N0CFP && !N1CFP) return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N1, N0); // fold (fmul A, 0) -> 0 - if (UnsafeFPMath && N1CFP && N1CFP->getValueAPF().isZero()) + if (DAG.getTarget().Options.UnsafeFPMath && + N1CFP && N1CFP->getValueAPF().isZero()) return N1; // fold (fmul A, 0) -> 0, vector edition. - if (UnsafeFPMath && ISD::isBuildVectorAllZeros(N1.getNode())) + if (DAG.getTarget().Options.UnsafeFPMath && + ISD::isBuildVectorAllZeros(N1.getNode())) return N1; // fold (fmul X, 2.0) -> (fadd X, X) if (N1CFP && N1CFP->isExactlyValue(+2.0)) @@ -5343,8 +5381,10 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) { return DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT, N0); // fold (fmul (fneg X), (fneg Y)) -> (fmul X, Y) - if (char LHSNeg = isNegatibleForFree(N0, LegalOperations)) { - if (char RHSNeg = isNegatibleForFree(N1, LegalOperations)) { + if (char LHSNeg = isNegatibleForFree(N0, LegalOperations, + &DAG.getTarget().Options)) { + if (char RHSNeg = isNegatibleForFree(N1, LegalOperations, + &DAG.getTarget().Options)) { // Both can be negated for free, check to see if at least one is cheaper // negated. if (LHSNeg == 2 || RHSNeg == 2) @@ -5355,7 +5395,8 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) { } // If allowed, fold (fmul (fmul x, c1), c2) -> (fmul x, (fmul c1, c2)) - if (UnsafeFPMath && N1CFP && N0.getOpcode() == ISD::FMUL && + if (DAG.getTarget().Options.UnsafeFPMath && + N1CFP && N0.getOpcode() == ISD::FMUL && N0.getNode()->hasOneUse() && isa<ConstantFPSDNode>(N0.getOperand(1))) return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N0.getOperand(0), DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, @@ -5383,8 +5424,10 @@ SDValue DAGCombiner::visitFDIV(SDNode *N) { // (fdiv (fneg X), (fneg Y)) -> (fdiv X, Y) - if (char LHSNeg = isNegatibleForFree(N0, LegalOperations)) { - if (char RHSNeg = isNegatibleForFree(N1, LegalOperations)) { + if (char LHSNeg = isNegatibleForFree(N0, LegalOperations, + &DAG.getTarget().Options)) { + if (char RHSNeg = isNegatibleForFree(N1, LegalOperations, + &DAG.getTarget().Options)) { // Both can be negated for free, check to see if at least one is cheaper // negated. if (LHSNeg == 2 || RHSNeg == 2) @@ -5637,7 +5680,7 @@ SDValue DAGCombiner::visitFNEG(SDNode *N) { SDValue N0 = N->getOperand(0); EVT VT = N->getValueType(0); - if (isNegatibleForFree(N0, LegalOperations)) + if (isNegatibleForFree(N0, LegalOperations, &DAG.getTarget().Options)) return GetNegatedExpression(N0, DAG, LegalOperations); // Transform fneg(bitconvert(x)) -> bitconvert(x^sign) to avoid loading @@ -7162,19 +7205,23 @@ SDValue DAGCombiner::visitEXTRACT_SUBVECTOR(SDNode* N) { if (NVT != SmallVT || NVT.getSizeInBits()*2 != BigVT.getSizeInBits()) return SDValue(); - // Combine: - // (extract_subvec (insert_subvec V1, V2, InsIdx), ExtIdx) - // Into: - // indicies are equal => V1 - // otherwise => (extract_subvec V1, ExtIdx) - // - SDValue InsIdx = N->getOperand(1); - SDValue ExtIdx = V->getOperand(2); - - if (InsIdx == ExtIdx) - return V->getOperand(1); - return DAG.getNode(ISD::EXTRACT_SUBVECTOR, N->getDebugLoc(), NVT, - V->getOperand(0), N->getOperand(1)); + // Only handle cases where both indexes are constants with the same type. + ConstantSDNode *InsIdx = dyn_cast<ConstantSDNode>(N->getOperand(1)); + ConstantSDNode *ExtIdx = dyn_cast<ConstantSDNode>(V->getOperand(2)); + + if (InsIdx && ExtIdx && + InsIdx->getValueType(0).getSizeInBits() <= 64 && + ExtIdx->getValueType(0).getSizeInBits() <= 64) { + // Combine: + // (extract_subvec (insert_subvec V1, V2, InsIdx), ExtIdx) + // Into: + // indices are equal => V1 + // otherwise => (extract_subvec V1, ExtIdx) + if (InsIdx->getZExtValue() == ExtIdx->getZExtValue()) + return V->getOperand(1); + return DAG.getNode(ISD::EXTRACT_SUBVECTOR, N->getDebugLoc(), NVT, + V->getOperand(0), N->getOperand(1)); + } } return SDValue(); |