diff options
Diffstat (limited to 'llvm/lib/Target/X86/X86ISelLowering.cpp')
| -rw-r--r-- | llvm/lib/Target/X86/X86ISelLowering.cpp | 145 |
1 files changed, 138 insertions, 7 deletions
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp index 624cff2..49beada 100644 --- a/llvm/lib/Target/X86/X86ISelLowering.cpp +++ b/llvm/lib/Target/X86/X86ISelLowering.cpp @@ -48778,10 +48778,9 @@ static SDValue combinePTESTCC(SDValue EFLAGS, X86::CondCode &CC, SDValue BC0 = peekThroughBitcasts(Op0); if (BC0.getOpcode() == X86ISD::PCMPEQ && ISD::isBuildVectorAllZeros(BC0.getOperand(1).getNode())) { - SDLoc DL(EFLAGS); CC = (CC == X86::COND_B ? X86::COND_E : X86::COND_NE); - SDValue X = DAG.getBitcast(OpVT, BC0.getOperand(0)); - return DAG.getNode(EFLAGS.getOpcode(), DL, VT, X, X); + SDValue X = DAG.getBitcast(OpVT, DAG.getFreeze(BC0.getOperand(0))); + return DAG.getNode(EFLAGS.getOpcode(), SDLoc(EFLAGS), VT, X, X); } } } @@ -48837,7 +48836,7 @@ static SDValue combinePTESTCC(SDValue EFLAGS, X86::CondCode &CC, MVT FloatSVT = MVT::getFloatingPointVT(EltBits); MVT FloatVT = MVT::getVectorVT(FloatSVT, OpVT.getSizeInBits() / EltBits); - Res = DAG.getBitcast(FloatVT, Res); + Res = DAG.getBitcast(FloatVT, DAG.getFreeze(Res)); return DAG.getNode(X86ISD::TESTP, SDLoc(EFLAGS), VT, Res, Res); } else if (EltBits == 16) { MVT MovmskVT = BCVT.is128BitVector() ? MVT::v16i8 : MVT::v32i8; @@ -48856,8 +48855,30 @@ static SDValue combinePTESTCC(SDValue EFLAGS, X86::CondCode &CC, } // TESTZ(X,-1) == TESTZ(X,X) - if (ISD::isBuildVectorAllOnes(Op1.getNode())) + if (ISD::isBuildVectorAllOnes(Op1.getNode())) { + Op0 = DAG.getFreeze(Op0); return DAG.getNode(EFLAGS.getOpcode(), SDLoc(EFLAGS), VT, Op0, Op0); + } + + // Attempt to convert PTESTZ(X,SIGNMASK) -> VTESTPD/PSZ(X,X) on AVX targets. + if (EFLAGS.getOpcode() == X86ISD::PTEST && Subtarget.hasAVX()) { + KnownBits KnownOp1 = DAG.computeKnownBits(Op1); + assert(KnownOp1.getBitWidth() == 64 && + "Illegal PTEST vector element width"); + if (KnownOp1.isConstant()) { + const APInt &Mask = KnownOp1.getConstant(); + if (Mask.isSignMask()) { + MVT FpVT = MVT::getVectorVT(MVT::f64, OpVT.getSizeInBits() / 64); + Op0 = DAG.getBitcast(FpVT, DAG.getFreeze(Op0)); + return DAG.getNode(X86ISD::TESTP, SDLoc(EFLAGS), VT, Op0, Op0); + } + if (Mask.isSplat(32) && Mask.trunc(32).isSignMask()) { + MVT FpVT = MVT::getVectorVT(MVT::f32, OpVT.getSizeInBits() / 32); + Op0 = DAG.getBitcast(FpVT, DAG.getFreeze(Op0)); + return DAG.getNode(X86ISD::TESTP, SDLoc(EFLAGS), VT, Op0, Op0); + } + } + } // TESTZ(OR(LO(X),HI(X)),OR(LO(Y),HI(Y))) -> TESTZ(X,Y) // TODO: Add COND_NE handling? @@ -53480,6 +53501,80 @@ static SDValue combineMaskedStore(SDNode *N, SelectionDAG &DAG, return SDValue(); } +// Look for a RMW operation that only touches one bit of a larger than legal +// type and fold it to a BTC/BTR/BTS pattern acting on a single i32 sub value. +static SDValue narrowBitOpRMW(StoreSDNode *St, const SDLoc &DL, + SelectionDAG &DAG, + const X86Subtarget &Subtarget) { + using namespace SDPatternMatch; + + // Only handle normal stores and its chain was a matching normal load. + auto *Ld = dyn_cast<LoadSDNode>(St->getChain()); + if (!ISD::isNormalStore(St) || !St->isSimple() || !Ld || + !ISD::isNormalLoad(Ld) || !Ld->isSimple() || + Ld->getBasePtr() != St->getBasePtr() || + Ld->getOffset() != St->getOffset()) + return SDValue(); + + SDValue LoadVal(Ld, 0); + SDValue StoredVal = St->getValue(); + EVT VT = StoredVal.getValueType(); + + // Only narrow larger than legal scalar integers. + if (!VT.isScalarInteger() || + VT.getSizeInBits() <= (Subtarget.is64Bit() ? 64 : 32)) + return SDValue(); + + // BTR: X & ~(1 << ShAmt) + // BTS: X | (1 << ShAmt) + // BTC: X ^ (1 << ShAmt) + SDValue ShAmt; + if (!StoredVal.hasOneUse() || + !(sd_match(StoredVal, m_And(m_Specific(LoadVal), + m_Not(m_Shl(m_One(), m_Value(ShAmt))))) || + sd_match(StoredVal, + m_Or(m_Specific(LoadVal), m_Shl(m_One(), m_Value(ShAmt)))) || + sd_match(StoredVal, + m_Xor(m_Specific(LoadVal), m_Shl(m_One(), m_Value(ShAmt)))))) + return SDValue(); + + // Ensure the shift amount is in bounds. + KnownBits KnownAmt = DAG.computeKnownBits(ShAmt); + if (KnownAmt.getMaxValue().uge(VT.getSizeInBits())) + return SDValue(); + + // Split the shift into an alignment shift that moves the active i32 block to + // the bottom bits for truncation and a modulo shift that can act on the i32. + EVT AmtVT = ShAmt.getValueType(); + SDValue AlignAmt = DAG.getNode(ISD::AND, DL, AmtVT, ShAmt, + DAG.getSignedConstant(-32LL, DL, AmtVT)); + SDValue ModuloAmt = + DAG.getNode(ISD::AND, DL, AmtVT, ShAmt, DAG.getConstant(31, DL, AmtVT)); + + // Compute the byte offset for the i32 block that is changed by the RMW. + // combineTruncate will adjust the load for us in a similar way. + EVT PtrVT = St->getBasePtr().getValueType(); + SDValue PtrBitOfs = DAG.getZExtOrTrunc(AlignAmt, DL, PtrVT); + SDValue PtrByteOfs = DAG.getNode(ISD::SRL, DL, PtrVT, PtrBitOfs, + DAG.getShiftAmountConstant(3, PtrVT, DL)); + SDValue NewPtr = DAG.getMemBasePlusOffset(St->getBasePtr(), PtrByteOfs, DL, + SDNodeFlags::NoUnsignedWrap); + + // Reconstruct the BTC/BTR/BTS pattern for the i32 block and store. + SDValue X = DAG.getNode(ISD::SRL, DL, VT, LoadVal, AlignAmt); + X = DAG.getNode(ISD::TRUNCATE, DL, MVT::i32, X); + + SDValue Mask = + DAG.getNode(ISD::SHL, DL, MVT::i32, DAG.getConstant(1, DL, MVT::i32), + DAG.getZExtOrTrunc(ModuloAmt, DL, MVT::i8)); + if (StoredVal.getOpcode() == ISD::AND) + Mask = DAG.getNOT(DL, Mask, MVT::i32); + + SDValue Res = DAG.getNode(StoredVal.getOpcode(), DL, MVT::i32, X, Mask); + return DAG.getStore(St->getChain(), DL, Res, NewPtr, St->getPointerInfo(), + Align(), St->getMemOperand()->getFlags()); +} + static SDValue combineStore(SDNode *N, SelectionDAG &DAG, TargetLowering::DAGCombinerInfo &DCI, const X86Subtarget &Subtarget) { @@ -53706,6 +53801,9 @@ static SDValue combineStore(SDNode *N, SelectionDAG &DAG, } } + if (SDValue R = narrowBitOpRMW(St, dl, DAG, Subtarget)) + return R; + // Convert store(cmov(load(p), x, CC), p) to cstore(x, p, CC) // store(cmov(x, load(p), CC), p) to cstore(x, p, InvertCC) if ((VT == MVT::i16 || VT == MVT::i32 || VT == MVT::i64) && @@ -54660,8 +54758,9 @@ static SDValue combineTruncate(SDNode *N, SelectionDAG &DAG, // truncation, see if we can convert the shift into a pointer offset instead. // Limit this to normal (non-ext) scalar integer loads. if (SrcVT.isScalarInteger() && Src.getOpcode() == ISD::SRL && - Src.hasOneUse() && Src.getOperand(0).hasOneUse() && - ISD::isNormalLoad(Src.getOperand(0).getNode())) { + Src.hasOneUse() && ISD::isNormalLoad(Src.getOperand(0).getNode()) && + (Src.getOperand(0).hasOneUse() || + !DAG.getTargetLoweringInfo().isOperationLegal(ISD::LOAD, SrcVT))) { auto *Ld = cast<LoadSDNode>(Src.getOperand(0)); if (Ld->isSimple() && VT.isByteSized() && isPowerOf2_64(VT.getSizeInBits())) { @@ -56459,6 +56558,7 @@ static SDValue combineAVX512SetCCToKMOV(EVT VT, SDValue Op0, ISD::CondCode CC, static SDValue combineSetCC(SDNode *N, SelectionDAG &DAG, TargetLowering::DAGCombinerInfo &DCI, const X86Subtarget &Subtarget) { + using namespace SDPatternMatch; const ISD::CondCode CC = cast<CondCodeSDNode>(N->getOperand(2))->get(); const SDValue LHS = N->getOperand(0); const SDValue RHS = N->getOperand(1); @@ -56517,6 +56617,37 @@ static SDValue combineSetCC(SDNode *N, SelectionDAG &DAG, if (SDValue AndN = MatchAndCmpEq(RHS, LHS)) return DAG.getSetCC(DL, VT, AndN, DAG.getConstant(0, DL, OpVT), CC); + // If we're performing a bit test on a larger than legal type, attempt + // to (aligned) shift down the value to the bottom 32-bits and then + // perform the bittest on the i32 value. + // ICMP_ZERO(AND(X,SHL(1,IDX))) + // --> ICMP_ZERO(AND(TRUNC(SRL(X,AND(IDX,-32))),SHL(1,AND(IDX,31)))) + if (isNullConstant(RHS) && + OpVT.getScalarSizeInBits() > (Subtarget.is64Bit() ? 64 : 32)) { + SDValue X, ShAmt; + if (sd_match(LHS, m_OneUse(m_And(m_Value(X), + m_Shl(m_One(), m_Value(ShAmt)))))) { + // Only attempt this if the shift amount is known to be in bounds. + KnownBits KnownAmt = DAG.computeKnownBits(ShAmt); + if (KnownAmt.getMaxValue().ult(OpVT.getScalarSizeInBits())) { + EVT AmtVT = ShAmt.getValueType(); + SDValue AlignAmt = + DAG.getNode(ISD::AND, DL, AmtVT, ShAmt, + DAG.getSignedConstant(-32LL, DL, AmtVT)); + SDValue ModuloAmt = DAG.getNode(ISD::AND, DL, AmtVT, ShAmt, + DAG.getConstant(31, DL, AmtVT)); + SDValue Mask = DAG.getNode( + ISD::SHL, DL, MVT::i32, DAG.getConstant(1, DL, MVT::i32), + DAG.getZExtOrTrunc(ModuloAmt, DL, MVT::i8)); + X = DAG.getNode(ISD::SRL, DL, OpVT, X, AlignAmt); + X = DAG.getNode(ISD::TRUNCATE, DL, MVT::i32, X); + X = DAG.getNode(ISD::AND, DL, MVT::i32, X, Mask); + return DAG.getSetCC(DL, VT, X, DAG.getConstant(0, DL, MVT::i32), + CC); + } + } + } + // cmpeq(trunc(x),C) --> cmpeq(x,C) // cmpne(trunc(x),C) --> cmpne(x,C) // iff x upper bits are zero. |