//===-------- LegalizeTypesGeneric.cpp - Generic type legalization --------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file implements generic type expansion and splitting for LegalizeTypes. // The routines here perform legalization when the details of the type (such as // whether it is an integer or a float) do not matter. // Expansion is the act of changing a computation in an illegal type to be a // computation in two identical registers of a smaller type. // Splitting is the act of changing a computation in an illegal type to be a // computation in two not necessarily identical registers of a smaller type. // //===----------------------------------------------------------------------===// #include "LegalizeTypes.h" #include "llvm/Target/TargetData.h" #include "llvm/CodeGen/PseudoSourceValue.h" using namespace llvm; //===----------------------------------------------------------------------===// // Generic Result Expansion. //===----------------------------------------------------------------------===// // These routines assume that the Lo/Hi part is stored first in memory on // little/big-endian machines, followed by the Hi/Lo part. This means that // they cannot be used as is on vectors, for which Lo is always stored first. void DAGTypeLegalizer::ExpandRes_BIT_CONVERT(SDNode *N, SDValue &Lo, SDValue &Hi) { MVT OutVT = N->getValueType(0); MVT NOutVT = TLI.getTypeToTransformTo(OutVT); SDValue InOp = N->getOperand(0); MVT InVT = InOp.getValueType(); // Handle some special cases efficiently. switch (getTypeAction(InVT)) { default: assert(false && "Unknown type action!"); case Legal: case PromoteInteger: break; case SoftenFloat: // Convert the integer operand instead. SplitInteger(GetSoftenedFloat(InOp), Lo, Hi); Lo = DAG.getNode(ISD::BIT_CONVERT, NOutVT, Lo); Hi = DAG.getNode(ISD::BIT_CONVERT, NOutVT, Hi); return; case ExpandInteger: case ExpandFloat: // Convert the expanded pieces of the input. GetExpandedOp(InOp, Lo, Hi); Lo = DAG.getNode(ISD::BIT_CONVERT, NOutVT, Lo); Hi = DAG.getNode(ISD::BIT_CONVERT, NOutVT, Hi); return; case SplitVector: // Convert the split parts of the input if it was split in two. GetSplitVector(InOp, Lo, Hi); if (Lo.getValueType() == Hi.getValueType()) { if (TLI.isBigEndian()) std::swap(Lo, Hi); Lo = DAG.getNode(ISD::BIT_CONVERT, NOutVT, Lo); Hi = DAG.getNode(ISD::BIT_CONVERT, NOutVT, Hi); return; } break; case ScalarizeVector: // Convert the element instead. SplitInteger(BitConvertToInteger(GetScalarizedVector(InOp)), Lo, Hi); Lo = DAG.getNode(ISD::BIT_CONVERT, NOutVT, Lo); Hi = DAG.getNode(ISD::BIT_CONVERT, NOutVT, Hi); return; } // Lower the bit-convert to a store/load from the stack. assert(NOutVT.isByteSized() && "Expanded type not byte sized!"); // Create the stack frame object. Make sure it is aligned for both // the source and expanded destination types. unsigned Alignment = TLI.getTargetData()->getPrefTypeAlignment(NOutVT.getTypeForMVT()); SDValue StackPtr = DAG.CreateStackTemporary(InVT, Alignment); int SPFI = cast(StackPtr.getNode())->getIndex(); const Value *SV = PseudoSourceValue::getFixedStack(SPFI); // Emit a store to the stack slot. SDValue Store = DAG.getStore(DAG.getEntryNode(), InOp, StackPtr, SV, 0); // Load the first half from the stack slot. Lo = DAG.getLoad(NOutVT, Store, StackPtr, SV, 0); // Increment the pointer to the other half. unsigned IncrementSize = NOutVT.getSizeInBits() / 8; StackPtr = DAG.getNode(ISD::ADD, StackPtr.getValueType(), StackPtr, DAG.getIntPtrConstant(IncrementSize)); // Load the second half from the stack slot. Hi = DAG.getLoad(NOutVT, Store, StackPtr, SV, IncrementSize, false, MinAlign(Alignment, IncrementSize)); // Handle endianness of the load. if (TLI.isBigEndian()) std::swap(Lo, Hi); } void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo, SDValue &Hi) { // Return the operands. Lo = N->getOperand(0); Hi = N->getOperand(1); } void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo, SDValue &Hi) { GetExpandedOp(N->getOperand(0), Lo, Hi); SDValue Part = cast(N->getOperand(1))->getZExtValue() ? Hi : Lo; assert(Part.getValueType() == N->getValueType(0) && "Type twice as big as expanded type not itself expanded!"); MVT NVT = TLI.getTypeToTransformTo(N->getValueType(0)); Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, NVT, Part, DAG.getConstant(0, TLI.getPointerTy())); Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, NVT, Part, DAG.getConstant(1, TLI.getPointerTy())); } void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo, SDValue &Hi) { SDValue OldVec = N->getOperand(0); unsigned OldElts = OldVec.getValueType().getVectorNumElements(); // Convert to a vector of the expanded element type, for example // <3 x i64> -> <6 x i32>. MVT OldVT = N->getValueType(0); MVT NewVT = TLI.getTypeToTransformTo(OldVT); SDValue NewVec = DAG.getNode(ISD::BIT_CONVERT, MVT::getVectorVT(NewVT, 2*OldElts), OldVec); // Extract the elements at 2 * Idx and 2 * Idx + 1 from the new vector. SDValue Idx = N->getOperand(1); // Make sure the type of Idx is big enough to hold the new values. if (Idx.getValueType().bitsLT(TLI.getPointerTy())) Idx = DAG.getNode(ISD::ZERO_EXTEND, TLI.getPointerTy(), Idx); Idx = DAG.getNode(ISD::ADD, Idx.getValueType(), Idx, Idx); Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, NewVT, NewVec, Idx); Idx = DAG.getNode(ISD::ADD, Idx.getValueType(), Idx, DAG.getConstant(1, Idx.getValueType())); Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, NewVT, NewVec, Idx); if (TLI.isBigEndian()) std::swap(Lo, Hi); } void DAGTypeLegalizer::ExpandRes_NormalLoad(SDNode *N, SDValue &Lo, SDValue &Hi) { assert(ISD::isNormalLoad(N) && "This routine only for normal loads!"); LoadSDNode *LD = cast(N); MVT NVT = TLI.getTypeToTransformTo(LD->getValueType(0)); SDValue Chain = LD->getChain(); SDValue Ptr = LD->getBasePtr(); int SVOffset = LD->getSrcValueOffset(); unsigned Alignment = LD->getAlignment(); bool isVolatile = LD->isVolatile(); assert(NVT.isByteSized() && "Expanded type not byte sized!"); Lo = DAG.getLoad(NVT, Chain, Ptr, LD->getSrcValue(), SVOffset, isVolatile, Alignment); // Increment the pointer to the other half. unsigned IncrementSize = NVT.getSizeInBits() / 8; Ptr = DAG.getNode(ISD::ADD, Ptr.getValueType(), Ptr, DAG.getIntPtrConstant(IncrementSize)); Hi = DAG.getLoad(NVT, Chain, Ptr, LD->getSrcValue(), SVOffset+IncrementSize, isVolatile, MinAlign(Alignment, IncrementSize)); // Build a factor node to remember that this load is independent of the // other one. Chain = DAG.getNode(ISD::TokenFactor, MVT::Other, Lo.getValue(1), Hi.getValue(1)); // Handle endianness of the load. if (TLI.isBigEndian()) std::swap(Lo, Hi); // Modified the chain - switch anything that used the old chain to use // the new one. ReplaceValueWith(SDValue(N, 1), Chain); } void DAGTypeLegalizer::ExpandRes_VAARG(SDNode *N, SDValue &Lo, SDValue &Hi) { MVT NVT = TLI.getTypeToTransformTo(N->getValueType(0)); SDValue Chain = N->getOperand(0); SDValue Ptr = N->getOperand(1); Lo = DAG.getVAArg(NVT, Chain, Ptr, N->getOperand(2)); Hi = DAG.getVAArg(NVT, Lo.getValue(1), Ptr, N->getOperand(2)); // Handle endianness of the load. if (TLI.isBigEndian()) std::swap(Lo, Hi); // Modified the chain - switch anything that used the old chain to use // the new one. ReplaceValueWith(SDValue(N, 1), Hi.getValue(1)); } //===--------------------------------------------------------------------===// // Generic Operand Expansion. //===--------------------------------------------------------------------===// SDValue DAGTypeLegalizer::ExpandOp_BIT_CONVERT(SDNode *N) { if (N->getValueType(0).isVector()) { // An illegal expanding type is being converted to a legal vector type. // Make a two element vector out of the expanded parts and convert that // instead, but only if the new vector type is legal (otherwise there // is no point, and it might create expansion loops). For example, on // x86 this turns v1i64 = BIT_CONVERT i64 into v1i64 = BIT_CONVERT v2i32. MVT OVT = N->getOperand(0).getValueType(); MVT NVT = MVT::getVectorVT(TLI.getTypeToTransformTo(OVT), 2); if (isTypeLegal(NVT)) { SDValue Parts[2]; GetExpandedOp(N->getOperand(0), Parts[0], Parts[1]); if (TLI.isBigEndian()) std::swap(Parts[0], Parts[1]); SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, NVT, Parts, 2); return DAG.getNode(ISD::BIT_CONVERT, N->getValueType(0), Vec); } } // Otherwise, store to a temporary and load out again as the new type. return CreateStackStoreLoad(N->getOperand(0), N->getValueType(0)); } SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) { // The vector type is legal but the element type needs expansion. MVT VecVT = N->getValueType(0); unsigned NumElts = VecVT.getVectorNumElements(); MVT OldVT = N->getOperand(0).getValueType(); MVT NewVT = TLI.getTypeToTransformTo(OldVT); // Build a vector of twice the length out of the expanded elements. // For example <3 x i64> -> <6 x i32>. std::vector NewElts; NewElts.reserve(NumElts*2); for (unsigned i = 0; i < NumElts; ++i) { SDValue Lo, Hi; GetExpandedOp(N->getOperand(i), Lo, Hi); if (TLI.isBigEndian()) std::swap(Lo, Hi); NewElts.push_back(Lo); NewElts.push_back(Hi); } SDValue NewVec = DAG.getNode(ISD::BUILD_VECTOR, MVT::getVectorVT(NewVT, NewElts.size()), &NewElts[0], NewElts.size()); // Convert the new vector to the old vector type. return DAG.getNode(ISD::BIT_CONVERT, VecVT, NewVec); } SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) { SDValue Lo, Hi; GetExpandedOp(N->getOperand(0), Lo, Hi); return cast(N->getOperand(1))->getZExtValue() ? Hi : Lo; } SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) { // The vector type is legal but the element type needs expansion. MVT VecVT = N->getValueType(0); unsigned NumElts = VecVT.getVectorNumElements(); SDValue Val = N->getOperand(1); MVT OldEVT = Val.getValueType(); MVT NewEVT = TLI.getTypeToTransformTo(OldEVT); assert(OldEVT == VecVT.getVectorElementType() && "Inserted element type doesn't match vector element type!"); // Bitconvert to a vector of twice the length with elements of the expanded // type, insert the expanded vector elements, and then convert back. MVT NewVecVT = MVT::getVectorVT(NewEVT, NumElts*2); SDValue NewVec = DAG.getNode(ISD::BIT_CONVERT, NewVecVT, N->getOperand(0)); SDValue Lo, Hi; GetExpandedOp(Val, Lo, Hi); if (TLI.isBigEndian()) std::swap(Lo, Hi); SDValue Idx = N->getOperand(2); Idx = DAG.getNode(ISD::ADD, Idx.getValueType(), Idx, Idx); NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, NewVecVT, NewVec, Lo, Idx); Idx = DAG.getNode(ISD::ADD,Idx.getValueType(), Idx, DAG.getIntPtrConstant(1)); NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, NewVecVT, NewVec, Hi, Idx); // Convert the new vector to the old vector type. return DAG.getNode(ISD::BIT_CONVERT, VecVT, NewVec); } SDValue DAGTypeLegalizer::ExpandOp_SCALAR_TO_VECTOR(SDNode *N) { MVT VT = N->getValueType(0); unsigned NumElts = VT.getVectorNumElements(); SmallVector Ops(NumElts); Ops[0] = N->getOperand(0); SDValue UndefVal = DAG.getNode(ISD::UNDEF, Ops[0].getValueType()); for (unsigned i = 1; i < NumElts; ++i) Ops[i] = UndefVal; return DAG.getNode(ISD::BUILD_VECTOR, VT, &Ops[0], NumElts); } SDValue DAGTypeLegalizer::ExpandOp_NormalStore(SDNode *N, unsigned OpNo) { assert(ISD::isNormalStore(N) && "This routine only for normal stores!"); assert(OpNo == 1 && "Can only expand the stored value so far"); StoreSDNode *St = cast(N); MVT NVT = TLI.getTypeToTransformTo(St->getValue().getValueType()); SDValue Chain = St->getChain(); SDValue Ptr = St->getBasePtr(); int SVOffset = St->getSrcValueOffset(); unsigned Alignment = St->getAlignment(); bool isVolatile = St->isVolatile(); assert(NVT.isByteSized() && "Expanded type not byte sized!"); unsigned IncrementSize = NVT.getSizeInBits() / 8; SDValue Lo, Hi; GetExpandedOp(St->getValue(), Lo, Hi); if (TLI.isBigEndian()) std::swap(Lo, Hi); Lo = DAG.getStore(Chain, Lo, Ptr, St->getSrcValue(), SVOffset, isVolatile, Alignment); Ptr = DAG.getNode(ISD::ADD, Ptr.getValueType(), Ptr, DAG.getIntPtrConstant(IncrementSize)); assert(isTypeLegal(Ptr.getValueType()) && "Pointers must be legal!"); Hi = DAG.getStore(Chain, Hi, Ptr, St->getSrcValue(), SVOffset + IncrementSize, isVolatile, MinAlign(Alignment, IncrementSize)); return DAG.getNode(ISD::TokenFactor, MVT::Other, Lo, Hi); } //===--------------------------------------------------------------------===// // Generic Result Splitting. //===--------------------------------------------------------------------===// // Be careful to make no assumptions about which of Lo/Hi is stored first in // memory (for vectors it is always Lo first followed by Hi in the following // bytes; for integers and floats it is Lo first if and only if the machine is // little-endian). void DAGTypeLegalizer::SplitRes_MERGE_VALUES(SDNode *N, SDValue &Lo, SDValue &Hi) { // A MERGE_VALUES node can produce any number of values. We know that the // first illegal one needs to be expanded into Lo/Hi. unsigned i; // The string of legal results gets turned into input operands, which have // the same type. for (i = 0; isTypeLegal(N->getValueType(i)); ++i) ReplaceValueWith(SDValue(N, i), SDValue(N->getOperand(i))); // The first illegal result must be the one that needs to be expanded. GetSplitOp(N->getOperand(i), Lo, Hi); // Legalize the rest of the results into the input operands whether they are // legal or not. unsigned e = N->getNumValues(); for (++i; i != e; ++i) ReplaceValueWith(SDValue(N, i), SDValue(N->getOperand(i))); } void DAGTypeLegalizer::SplitRes_SELECT(SDNode *N, SDValue &Lo, SDValue &Hi) { SDValue LL, LH, RL, RH; GetSplitOp(N->getOperand(1), LL, LH); GetSplitOp(N->getOperand(2), RL, RH); SDValue Cond = N->getOperand(0); Lo = DAG.getNode(ISD::SELECT, LL.getValueType(), Cond, LL, RL); Hi = DAG.getNode(ISD::SELECT, LH.getValueType(), Cond, LH, RH); } void DAGTypeLegalizer::SplitRes_SELECT_CC(SDNode *N, SDValue &Lo, SDValue &Hi) { SDValue LL, LH, RL, RH; GetSplitOp(N->getOperand(2), LL, LH); GetSplitOp(N->getOperand(3), RL, RH); Lo = DAG.getNode(ISD::SELECT_CC, LL.getValueType(), N->getOperand(0), N->getOperand(1), LL, RL, N->getOperand(4)); Hi = DAG.getNode(ISD::SELECT_CC, LH.getValueType(), N->getOperand(0), N->getOperand(1), LH, RH, N->getOperand(4)); } void DAGTypeLegalizer::SplitRes_UNDEF(SDNode *N, SDValue &Lo, SDValue &Hi) { MVT LoVT, HiVT; GetSplitDestVTs(N->getValueType(0), LoVT, HiVT); Lo = DAG.getNode(ISD::UNDEF, LoVT); Hi = DAG.getNode(ISD::UNDEF, HiVT); }