diff options
Diffstat (limited to 'contrib/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
-rw-r--r-- | contrib/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 238 |
1 files changed, 168 insertions, 70 deletions
diff --git a/contrib/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/contrib/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index eb16095..2e09ec0 100644 --- a/contrib/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/contrib/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -205,6 +205,7 @@ namespace { SDValue visitCTTZ_ZERO_UNDEF(SDNode *N); SDValue visitCTPOP(SDNode *N); SDValue visitSELECT(SDNode *N); + SDValue visitVSELECT(SDNode *N); SDValue visitSELECT_CC(SDNode *N); SDValue visitSETCC(SDNode *N); SDValue visitSIGN_EXTEND(SDNode *N); @@ -243,7 +244,6 @@ namespace { SDValue visitCONCAT_VECTORS(SDNode *N); SDValue visitEXTRACT_SUBVECTOR(SDNode *N); SDValue visitVECTOR_SHUFFLE(SDNode *N); - SDValue visitMEMBARRIER(SDNode *N); SDValue XformToShuffleWithZero(SDNode *N); SDValue ReassociateOps(unsigned Opc, DebugLoc DL, SDValue LHS, SDValue RHS); @@ -1127,6 +1127,7 @@ SDValue DAGCombiner::visit(SDNode *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::VSELECT: return visitVSELECT(N); case ISD::SELECT_CC: return visitSELECT_CC(N); case ISD::SETCC: return visitSETCC(N); case ISD::SIGN_EXTEND: return visitSIGN_EXTEND(N); @@ -1165,7 +1166,6 @@ SDValue DAGCombiner::visit(SDNode *N) { case ISD::CONCAT_VECTORS: return visitCONCAT_VECTORS(N); case ISD::EXTRACT_SUBVECTOR: return visitEXTRACT_SUBVECTOR(N); case ISD::VECTOR_SHUFFLE: return visitVECTOR_SHUFFLE(N); - case ISD::MEMBARRIER: return visitMEMBARRIER(N); } return SDValue(); } @@ -4164,6 +4164,46 @@ SDValue DAGCombiner::visitSELECT(SDNode *N) { return SDValue(); } +SDValue DAGCombiner::visitVSELECT(SDNode *N) { + SDValue N0 = N->getOperand(0); + SDValue N1 = N->getOperand(1); + SDValue N2 = N->getOperand(2); + DebugLoc DL = N->getDebugLoc(); + + // Canonicalize integer abs. + // vselect (setg[te] X, 0), X, -X -> + // vselect (setgt X, -1), X, -X -> + // vselect (setl[te] X, 0), -X, X -> + // Y = sra (X, size(X)-1); xor (add (X, Y), Y) + if (N0.getOpcode() == ISD::SETCC) { + SDValue LHS = N0.getOperand(0), RHS = N0.getOperand(1); + ISD::CondCode CC = cast<CondCodeSDNode>(N0.getOperand(2))->get(); + bool isAbs = false; + bool RHSIsAllZeros = ISD::isBuildVectorAllZeros(RHS.getNode()); + + if (((RHSIsAllZeros && (CC == ISD::SETGT || CC == ISD::SETGE)) || + (ISD::isBuildVectorAllOnes(RHS.getNode()) && CC == ISD::SETGT)) && + N1 == LHS && N2.getOpcode() == ISD::SUB && N1 == N2.getOperand(1)) + isAbs = ISD::isBuildVectorAllZeros(N2.getOperand(0).getNode()); + else if ((RHSIsAllZeros && (CC == ISD::SETLT || CC == ISD::SETLE)) && + N2 == LHS && N1.getOpcode() == ISD::SUB && N2 == N1.getOperand(1)) + isAbs = ISD::isBuildVectorAllZeros(N1.getOperand(0).getNode()); + + if (isAbs) { + EVT VT = LHS.getValueType(); + SDValue Shift = DAG.getNode( + ISD::SRA, DL, VT, LHS, + DAG.getConstant(VT.getScalarType().getSizeInBits() - 1, VT)); + SDValue Add = DAG.getNode(ISD::ADD, DL, VT, LHS, Shift); + AddToWorkList(Shift.getNode()); + AddToWorkList(Add.getNode()); + return DAG.getNode(ISD::XOR, DL, VT, Add, Shift); + } + } + + return SDValue(); +} + SDValue DAGCombiner::visitSELECT_CC(SDNode *N) { SDValue N0 = N->getOperand(0); SDValue N1 = N->getOperand(1); @@ -4453,7 +4493,9 @@ SDValue DAGCombiner::visitSIGN_EXTEND(SDNode *N) { if (N0.getOpcode() == ISD::SETCC) { // sext(setcc) -> sext_in_reg(vsetcc) for vectors. // Only do this before legalize for now. - if (VT.isVector() && !LegalOperations) { + if (VT.isVector() && !LegalOperations && + TLI.getBooleanContents(true) == + TargetLowering::ZeroOrNegativeOneBooleanContent) { EVT N0VT = N0.getOperand(0).getValueType(); // On some architectures (such as SSE/NEON/etc) the SETCC result type is // of the same size as the compared operands. Only optimize sext(setcc()) @@ -7110,25 +7152,40 @@ bool DAGCombiner::CombineToPreIndexedLoadStore(SDNode *N) { assert(OtherUses[i]->getOperand(!OffsetIdx).getNode() == BasePtr.getNode() && "Expected BasePtr operand"); - APInt OV = - cast<ConstantSDNode>(Offset)->getAPIntValue(); - if (AM == ISD::PRE_DEC) - OV = -OV; + // We need to replace ptr0 in the following expression: + // x0 * offset0 + y0 * ptr0 = t0 + // knowing that + // x1 * offset1 + y1 * ptr0 = t1 (the indexed load/store) + // + // where x0, x1, y0 and y1 in {-1, 1} are given by the types of the + // indexed load/store and the expresion that needs to be re-written. + // + // Therefore, we have: + // t0 = (x0 * offset0 - x1 * y0 * y1 *offset1) + (y0 * y1) * t1 ConstantSDNode *CN = cast<ConstantSDNode>(OtherUses[i]->getOperand(OffsetIdx)); - APInt CNV = CN->getAPIntValue(); - if (OtherUses[i]->getOpcode() == ISD::SUB && OffsetIdx == 1) - CNV += OV; - else - CNV -= OV; + int X0, X1, Y0, Y1; + APInt Offset0 = CN->getAPIntValue(); + APInt Offset1 = cast<ConstantSDNode>(Offset)->getAPIntValue(); - SDValue NewOp1 = Result.getValue(isLoad ? 1 : 0); - SDValue NewOp2 = DAG.getConstant(CNV, CN->getValueType(0)); - if (OffsetIdx == 0) - std::swap(NewOp1, NewOp2); + X0 = (OtherUses[i]->getOpcode() == ISD::SUB && OffsetIdx == 1) ? -1 : 1; + Y0 = (OtherUses[i]->getOpcode() == ISD::SUB && OffsetIdx == 0) ? -1 : 1; + X1 = (AM == ISD::PRE_DEC && !Swapped) ? -1 : 1; + Y1 = (AM == ISD::PRE_DEC && Swapped) ? -1 : 1; - SDValue NewUse = DAG.getNode(OtherUses[i]->getOpcode(), + unsigned Opcode = (Y0 * Y1 < 0) ? ISD::SUB : ISD::ADD; + + APInt CNV = Offset0; + if (X0 < 0) CNV = -CNV; + if (X1 * Y0 * Y1 < 0) CNV = CNV + Offset1; + else CNV = CNV - Offset1; + + // We can now generate the new expression. + SDValue NewOp1 = DAG.getConstant(CNV, CN->getValueType(0)); + SDValue NewOp2 = Result.getValue(isLoad ? 1 : 0); + + SDValue NewUse = DAG.getNode(Opcode, OtherUses[i]->getDebugLoc(), OtherUses[i]->getValueType(0), NewOp1, NewOp2); DAG.ReplaceAllUsesOfValueWith(SDValue(OtherUses[i], 0), NewUse); @@ -9065,6 +9122,51 @@ SDValue DAGCombiner::visitCONCAT_VECTORS(SDNode *N) { if (ISD::allOperandsUndef(N)) return DAG.getUNDEF(N->getValueType(0)); + // Type legalization of vectors and DAG canonicalization of SHUFFLE_VECTOR + // nodes often generate nop CONCAT_VECTOR nodes. + // Scan the CONCAT_VECTOR operands and look for a CONCAT operations that + // place the incoming vectors at the exact same location. + SDValue SingleSource = SDValue(); + unsigned PartNumElem = N->getOperand(0).getValueType().getVectorNumElements(); + + for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) { + SDValue Op = N->getOperand(i); + + if (Op.getOpcode() == ISD::UNDEF) + continue; + + // Check if this is the identity extract: + if (Op.getOpcode() != ISD::EXTRACT_SUBVECTOR) + return SDValue(); + + // Find the single incoming vector for the extract_subvector. + if (SingleSource.getNode()) { + if (Op.getOperand(0) != SingleSource) + return SDValue(); + } else { + SingleSource = Op.getOperand(0); + + // Check the source type is the same as the type of the result. + // If not, this concat may extend the vector, so we can not + // optimize it away. + if (SingleSource.getValueType() != N->getValueType(0)) + return SDValue(); + } + + unsigned IdentityIndex = i * PartNumElem; + ConstantSDNode *CS = dyn_cast<ConstantSDNode>(Op.getOperand(1)); + // The extract index must be constant. + if (!CS) + return SDValue(); + + // Check that we are reading from the identity index. + if (CS->getZExtValue() != IdentityIndex) + return SDValue(); + } + + if (SingleSource.getNode()) + return SingleSource; + return SDValue(); } @@ -9125,6 +9227,44 @@ SDValue DAGCombiner::visitEXTRACT_SUBVECTOR(SDNode* N) { return SDValue(); } +// Tries to turn a shuffle of two CONCAT_VECTORS into a single concat. +static SDValue partitionShuffleOfConcats(SDNode *N, SelectionDAG &DAG) { + EVT VT = N->getValueType(0); + unsigned NumElts = VT.getVectorNumElements(); + + SDValue N0 = N->getOperand(0); + SDValue N1 = N->getOperand(1); + ShuffleVectorSDNode *SVN = cast<ShuffleVectorSDNode>(N); + + SmallVector<SDValue, 4> Ops; + EVT ConcatVT = N0.getOperand(0).getValueType(); + unsigned NumElemsPerConcat = ConcatVT.getVectorNumElements(); + unsigned NumConcats = NumElts / NumElemsPerConcat; + + // Look at every vector that's inserted. We're looking for exact + // subvector-sized copies from a concatenated vector + for (unsigned I = 0; I != NumConcats; ++I) { + // Make sure we're dealing with a copy. + unsigned Begin = I * NumElemsPerConcat; + if (SVN->getMaskElt(Begin) % NumElemsPerConcat != 0) + return SDValue(); + + for (unsigned J = 1; J != NumElemsPerConcat; ++J) { + if (SVN->getMaskElt(Begin + J - 1) + 1 != SVN->getMaskElt(Begin + J)) + return SDValue(); + } + + unsigned FirstElt = SVN->getMaskElt(Begin) / NumElemsPerConcat; + if (FirstElt < N0.getNumOperands()) + Ops.push_back(N0.getOperand(FirstElt)); + else + Ops.push_back(N1.getOperand(FirstElt - N0.getNumOperands())); + } + + return DAG.getNode(ISD::CONCAT_VECTORS, N->getDebugLoc(), VT, Ops.data(), + Ops.size()); +} + SDValue DAGCombiner::visitVECTOR_SHUFFLE(SDNode *N) { EVT VT = N->getValueType(0); unsigned NumElts = VT.getVectorNumElements(); @@ -9226,6 +9366,17 @@ SDValue DAGCombiner::visitVECTOR_SHUFFLE(SDNode *N) { } } + if (N0.getOpcode() == ISD::CONCAT_VECTORS && + Level < AfterLegalizeVectorOps && + (N1.getOpcode() == ISD::UNDEF || + (N1.getOpcode() == ISD::CONCAT_VECTORS && + N0.getOperand(0).getValueType() == N1.getOperand(0).getValueType()))) { + SDValue V = partitionShuffleOfConcats(N, DAG); + + if (V.getNode()) + return V; + } + // If this shuffle node is simply a swizzle of another shuffle node, // and it reverses the swizzle of the previous shuffle then we can // optimize shuffle(shuffle(x, undef), undef) -> x. @@ -9262,59 +9413,6 @@ SDValue DAGCombiner::visitVECTOR_SHUFFLE(SDNode *N) { return SDValue(); } -SDValue DAGCombiner::visitMEMBARRIER(SDNode* N) { - if (!TLI.getShouldFoldAtomicFences()) - return SDValue(); - - SDValue atomic = N->getOperand(0); - switch (atomic.getOpcode()) { - case ISD::ATOMIC_CMP_SWAP: - case ISD::ATOMIC_SWAP: - case ISD::ATOMIC_LOAD_ADD: - case ISD::ATOMIC_LOAD_SUB: - case ISD::ATOMIC_LOAD_AND: - case ISD::ATOMIC_LOAD_OR: - case ISD::ATOMIC_LOAD_XOR: - case ISD::ATOMIC_LOAD_NAND: - case ISD::ATOMIC_LOAD_MIN: - case ISD::ATOMIC_LOAD_MAX: - case ISD::ATOMIC_LOAD_UMIN: - case ISD::ATOMIC_LOAD_UMAX: - break; - default: - return SDValue(); - } - - SDValue fence = atomic.getOperand(0); - if (fence.getOpcode() != ISD::MEMBARRIER) - return SDValue(); - - switch (atomic.getOpcode()) { - case ISD::ATOMIC_CMP_SWAP: - return SDValue(DAG.UpdateNodeOperands(atomic.getNode(), - fence.getOperand(0), - atomic.getOperand(1), atomic.getOperand(2), - atomic.getOperand(3)), atomic.getResNo()); - case ISD::ATOMIC_SWAP: - case ISD::ATOMIC_LOAD_ADD: - case ISD::ATOMIC_LOAD_SUB: - case ISD::ATOMIC_LOAD_AND: - case ISD::ATOMIC_LOAD_OR: - case ISD::ATOMIC_LOAD_XOR: - case ISD::ATOMIC_LOAD_NAND: - case ISD::ATOMIC_LOAD_MIN: - case ISD::ATOMIC_LOAD_MAX: - case ISD::ATOMIC_LOAD_UMIN: - case ISD::ATOMIC_LOAD_UMAX: - return SDValue(DAG.UpdateNodeOperands(atomic.getNode(), - fence.getOperand(0), - atomic.getOperand(1), atomic.getOperand(2)), - atomic.getResNo()); - default: - return SDValue(); - } -} - /// XformToShuffleWithZero - Returns a vector_shuffle if it able to transform /// an AND to a vector_shuffle with the destination vector and a zero vector. /// e.g. AND V, <0xffffffff, 0, 0xffffffff, 0>. ==> |