llvm-6502/lib/Target/PIC16/PIC16ISelLowering.cpp
Sanjiv Gupta b1b5ffd827 Added a more function PIC16 backend. However to get this working a patch in
ExpandIntegerOperand (LegalizeIntegerTypes.cpp) is needed which is yet to be reworked and submitted. 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59617 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-19 11:00:54 +00:00

679 lines
24 KiB
C++

//===-- PIC16ISelLowering.cpp - PIC16 DAG Lowering Implementation ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the interfaces that PIC16 uses to lower LLVM code into a
// selection DAG.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "pic16-lower"
#include "PIC16ISelLowering.h"
#include "PIC16TargetMachine.h"
#include "llvm/DerivedTypes.h"
#include "llvm/GlobalValue.h"
#include "llvm/Function.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
using namespace llvm;
// PIC16TargetLowering Constructor.
PIC16TargetLowering::PIC16TargetLowering(PIC16TargetMachine &TM)
: TargetLowering(TM) {
Subtarget = &TM.getSubtarget<PIC16Subtarget>();
addRegisterClass(MVT::i8, PIC16::GPRRegisterClass);
setShiftAmountType(MVT::i8);
setShiftAmountFlavor(Extend);
setOperationAction(ISD::GlobalAddress, MVT::i16, Custom);
setOperationAction(ISD::LOAD, MVT::i8, Legal);
setOperationAction(ISD::LOAD, MVT::i16, Custom);
setOperationAction(ISD::LOAD, MVT::i32, Custom);
setOperationAction(ISD::STORE, MVT::i8, Legal);
setOperationAction(ISD::STORE, MVT::i16, Custom);
setOperationAction(ISD::STORE, MVT::i32, Custom);
setOperationAction(ISD::ADDE, MVT::i8, Custom);
setOperationAction(ISD::ADDC, MVT::i8, Custom);
setOperationAction(ISD::SUBE, MVT::i8, Custom);
setOperationAction(ISD::SUBC, MVT::i8, Custom);
setOperationAction(ISD::ADD, MVT::i8, Legal);
setOperationAction(ISD::ADD, MVT::i16, Custom);
setOperationAction(ISD::SHL, MVT::i16, Custom);
setOperationAction(ISD::SHL, MVT::i32, Custom);
//setOperationAction(ISD::TRUNCATE, MVT::i16, Custom);
setTruncStoreAction(MVT::i16, MVT::i8, Custom);
// Now deduce the information based on the above mentioned
// actions
computeRegisterProperties();
}
const char *PIC16TargetLowering::getTargetNodeName(unsigned Opcode) const {
switch (Opcode) {
default: return NULL;
case PIC16ISD::Lo: return "PIC16ISD::Lo";
case PIC16ISD::Hi: return "PIC16ISD::Hi";
case PIC16ISD::MTLO: return "PIC16ISD::MTLO";
case PIC16ISD::MTHI: return "PIC16ISD::MTHI";
case PIC16ISD::Banksel: return "PIC16ISD::Banksel";
case PIC16ISD::PIC16Load: return "PIC16ISD::PIC16Load";
case PIC16ISD::PIC16Store: return "PIC16ISD::PIC16Store";
case PIC16ISD::BCF: return "PIC16ISD::BCF";
case PIC16ISD::LSLF: return "PIC16ISD::LSLF";
case PIC16ISD::LRLF: return "PIC16ISD::LRLF";
case PIC16ISD::RLF: return "PIC16ISD::RLF";
case PIC16ISD::RRF: return "PIC16ISD::RRF";
case PIC16ISD::Dummy: return "PIC16ISD::Dummy";
}
}
SDNode *PIC16TargetLowering::ReplaceNodeResults(SDNode *N, SelectionDAG &DAG) {
switch (N->getOpcode()) {
case ISD::GlobalAddress:
return ExpandGlobalAddress(N, DAG);
case ISD::STORE:
return ExpandStore(N, DAG);
case ISD::LOAD:
return ExpandLoad(N, DAG);
case ISD::ADD:
return ExpandAdd(N, DAG);
case ISD::SHL:
return ExpandShift(N, DAG);
default:
assert (0 && "not implemented");
}
}
SDNode *PIC16TargetLowering::ExpandStore(SDNode *N, SelectionDAG &DAG) {
StoreSDNode *St = cast<StoreSDNode>(N);
SDValue Chain = St->getChain();
SDValue Src = St->getValue();
SDValue Ptr = St->getBasePtr();
MVT ValueType = Src.getValueType();
unsigned StoreOffset = 0;
SDValue PtrLo, PtrHi;
LegalizeAddress(Ptr, DAG, PtrLo, PtrHi, StoreOffset);
if (ValueType == MVT::i8) {
SDValue Store = DAG.getNode (PIC16ISD::PIC16Store, MVT::Other, Chain, Src,
PtrLo, PtrHi, DAG.getConstant (0, MVT::i8));
return Store.getNode();
}
else if (ValueType == MVT::i16) {
// Get the Lo and Hi parts from MERGE_VALUE or BUILD_PAIR.
SDValue SrcLo, SrcHi;
GetExpandedParts(Src, DAG, SrcLo, SrcHi);
SDValue ChainLo = Chain, ChainHi = Chain;
if (Chain.getOpcode() == ISD::TokenFactor) {
ChainLo = Chain.getOperand(0);
ChainHi = Chain.getOperand(1);
}
SDValue Store1 = DAG.getNode(PIC16ISD::PIC16Store, MVT::Other,
ChainLo,
SrcLo, PtrLo, PtrHi,
DAG.getConstant (0 + StoreOffset, MVT::i8));
SDValue Store2 = DAG.getNode(PIC16ISD::PIC16Store, MVT::Other, ChainHi,
SrcHi, PtrLo, PtrHi,
DAG.getConstant (1 + StoreOffset, MVT::i8));
return DAG.getNode(ISD::TokenFactor, MVT::Other, getChain(Store1),
getChain(Store2)).getNode();
}
else if (ValueType == MVT::i32) {
// Get the Lo and Hi parts from MERGE_VALUE or BUILD_PAIR.
SDValue SrcLo, SrcHi;
GetExpandedParts(Src, DAG, SrcLo, SrcHi);
// Get the expanded parts of each of SrcLo and SrcHi.
SDValue SrcLo1, SrcLo2, SrcHi1, SrcHi2;
GetExpandedParts(SrcLo, DAG, SrcLo1, SrcLo2);
GetExpandedParts(SrcHi, DAG, SrcHi1, SrcHi2);
SDValue ChainLo = Chain, ChainHi = Chain;
if (Chain.getOpcode() == ISD::TokenFactor) {
ChainLo = Chain.getOperand(0);
ChainHi = Chain.getOperand(1);
}
SDValue ChainLo1 = ChainLo, ChainLo2 = ChainLo, ChainHi1 = ChainHi,
ChainHi2 = ChainHi;
if (ChainLo.getOpcode() == ISD::TokenFactor) {
ChainLo1 = ChainLo.getOperand(0);
ChainLo2 = ChainLo.getOperand(1);
}
if (ChainHi.getOpcode() == ISD::TokenFactor) {
ChainHi1 = ChainHi.getOperand(0);
ChainHi2 = ChainHi.getOperand(1);
}
SDValue Store1 = DAG.getNode(PIC16ISD::PIC16Store, MVT::Other,
ChainLo1,
SrcLo1, PtrLo, PtrHi,
DAG.getConstant (0 + StoreOffset, MVT::i8));
SDValue Store2 = DAG.getNode(PIC16ISD::PIC16Store, MVT::Other, ChainLo2,
SrcLo2, PtrLo, PtrHi,
DAG.getConstant (1 + StoreOffset, MVT::i8));
SDValue Store3 = DAG.getNode(PIC16ISD::PIC16Store, MVT::Other, ChainHi1,
SrcHi1, PtrLo, PtrHi,
DAG.getConstant (2 + StoreOffset, MVT::i8));
SDValue Store4 = DAG.getNode(PIC16ISD::PIC16Store, MVT::Other, ChainHi2,
SrcHi2, PtrLo, PtrHi,
DAG.getConstant (3 + StoreOffset, MVT::i8));
SDValue RetLo = DAG.getNode(ISD::TokenFactor, MVT::Other, getChain(Store1),
getChain(Store2));
SDValue RetHi = DAG.getNode(ISD::TokenFactor, MVT::Other, getChain(Store3),
getChain(Store4));
return DAG.getNode(ISD::TokenFactor, MVT::Other, RetLo, RetHi).getNode();
}
else {
assert (0 && "value type not supported");
}
}
// ExpandGlobalAddress -
SDNode *PIC16TargetLowering::ExpandGlobalAddress(SDNode *N, SelectionDAG &DAG) {
GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(SDValue(N, 0));
SDValue TGA = DAG.getTargetGlobalAddress(G->getGlobal(), MVT::i8,
G->getOffset());
SDValue Lo = DAG.getNode(PIC16ISD::Lo, MVT::i8, TGA);
SDValue Hi = DAG.getNode(PIC16ISD::Hi, MVT::i8, TGA);
SDValue BP = DAG.getNode(ISD::BUILD_PAIR, MVT::i16, Lo, Hi);
return BP.getNode();
}
bool PIC16TargetLowering::isDirectAddress(const SDValue &Op) {
assert (Op.getNode() != NULL && "Can't operate on NULL SDNode!!");
if (Op.getOpcode() == ISD::BUILD_PAIR) {
if (Op.getOperand(0).getOpcode() == PIC16ISD::Lo)
return true;
}
return false;
}
// Return true if DirectAddress is in ROM_SPACE
bool PIC16TargetLowering::isRomAddress(const SDValue &Op) {
// RomAddress is a GlobalAddress in ROM_SPACE_
// If the Op is not a GlobalAddress return NULL without checking
// anything further.
if (!isDirectAddress(Op))
return false;
// Its a GlobalAddress.
// It is BUILD_PAIR((PIC16Lo TGA), (PIC16Hi TGA)) and Op is BUILD_PAIR
SDValue TGA = Op.getOperand(0).getOperand(0);
GlobalAddressSDNode *GSDN = dyn_cast<GlobalAddressSDNode>(TGA);
const Type *ValueType = GSDN->getGlobal()->getType();
if (!isa<PointerType>(ValueType)) {
assert(0 && "TGA must be of a PointerType");
}
int AddrSpace = dyn_cast<PointerType>(ValueType)->getAddressSpace();
if (AddrSpace == PIC16ISD::ROM_SPACE)
return true;
// Any other address space return it false
return false;
}
// To extract chain value from the SDValue Nodes
// This function will help to maintain the chain extracting
// code at one place. In case of any change in future it will
// help maintain the code.
SDValue PIC16TargetLowering::getChain(SDValue &Op) {
SDValue Chain = Op.getValue(Op.getNode()->getNumValues() - 1);
// All nodes may not produce a chain. Therefore following assert
// verifies that the node is returning a chain only.
assert (Chain.getValueType() == MVT::Other && "Node does not have a chain");
return Chain;
}
void PIC16TargetLowering::GetExpandedParts(SDValue Op, SelectionDAG &DAG,
SDValue &Lo, SDValue &Hi) {
SDNode *N = Op.getNode();
unsigned NumValues = N->getNumValues();
std::vector<MVT> VTs;
MVT NewVT;
std::vector<SDValue> Opers;
// EXTRACT_ELEMENT should have same number and type of values that the
// node replacing the EXTRACT_ELEMENT should have. (i.e. extracted element)
// Some nodes such as LOAD and PIC16Load have more than one values. In such
// cases EXTRACT_ELEMENT should have more than one values. Therefore creating
// vector of Values for EXTRACT_ELEMENT. This list will have same number of
// values as the extracted element will have.
for (unsigned i=0;i < NumValues; ++i) {
NewVT = getTypeToTransformTo(N->getValueType(i));
VTs.push_back(NewVT);
}
// extract the lo component
Opers.push_back(Op);
Opers.push_back(DAG.getConstant(0,MVT::i8));
Lo = DAG.getNode(ISD::EXTRACT_ELEMENT,VTs,&Opers[0],Opers.size());
// extract the hi component
Opers.clear();
Opers.push_back(Op);
Opers.push_back(DAG.getConstant(1,MVT::i8));
Hi = DAG.getNode(ISD::EXTRACT_ELEMENT,VTs,&Opers[0],Opers.size());
}
// This function legalizes the PIC16 Addresses. If the Pointer is
// -- Direct address variable residing
// --> then a Banksel for that variable will be created.
// -- Rom variable
// --> then it will be treated as an indirect address.
// -- Indirect address
// --> then the address will be loaded into FSR
// -- ADD with constant operand
// --> then constant operand of ADD will be returned as Offset
// and non-constant operand of ADD will be treated as pointer.
// Returns the high and lo part of the address, and the offset(in case of ADD).
void PIC16TargetLowering:: LegalizeAddress(SDValue Ptr, SelectionDAG &DAG,
SDValue &Lo, SDValue &Hi,
unsigned &Offset) {
// Offset, by default, should be 0
Offset = 0;
// If the pointer is ADD with constant,
// return the constant value as the offset
if (Ptr.getOpcode() == ISD::ADD) {
SDValue OperLeft = Ptr.getOperand(0);
SDValue OperRight = Ptr.getOperand(1);
if (OperLeft.getOpcode() == ISD::Constant) {
Offset = dyn_cast<ConstantSDNode>(OperLeft)->getZExtValue();
Ptr = OperRight;
} else {
Ptr = OperLeft;
Offset = dyn_cast<ConstantSDNode>(OperRight)->getZExtValue();
}
}
if (isDirectAddress(Ptr) && !isRomAddress(Ptr)) {
// Direct addressing case for RAM variables. The Hi part is constant
// and the Lo part is the TGA itself.
Lo = Ptr.getOperand(0).getOperand(0);
// For direct addresses Hi is a constant. Value 1 for the constant
// signifies that banksel needs to generated for it. Value 0 for
// the constant signifies that banksel does not need to be generated
// for it. Mark it as 1 now and optimize later.
Hi = DAG.getConstant(1, MVT::i8);
return;
}
// Indirect addresses. Get the hi and lo parts of ptr.
GetExpandedParts(Ptr, DAG, Lo, Hi);
// Put the hi and lo parts into FSR.
Lo = DAG.getNode(PIC16ISD::MTLO, MVT::i8, Lo);
Hi = DAG.getNode(PIC16ISD::MTHI, MVT::i8, Hi);
return;
}
SDNode *PIC16TargetLowering::ExpandAdd(SDNode *N, SelectionDAG &DAG) {
SDValue OperLeft = N->getOperand(0);
SDValue OperRight = N->getOperand(1);
if((OperLeft.getOpcode() == ISD::Constant) ||
(OperRight.getOpcode() == ISD::Constant)) {
return NULL;
}
// These case are yet to be handled
return NULL;
}
SDNode *PIC16TargetLowering::ExpandLoad(SDNode *N, SelectionDAG &DAG) {
LoadSDNode *LD = dyn_cast<LoadSDNode>(SDValue(N, 0));
SDValue Chain = LD->getChain();
SDValue Ptr = LD->getBasePtr();
SDValue Load, Offset;
SDVTList Tys;
MVT VT, NewVT;
SDValue PtrLo, PtrHi;
unsigned LoadOffset;
// Legalize direct/indirect addresses. This will give the lo and hi parts
// of the address and the offset.
LegalizeAddress(Ptr, DAG, PtrLo, PtrHi, LoadOffset);
// Load from the pointer (direct address or FSR)
VT = N->getValueType(0);
unsigned NumLoads = VT.getSizeInBits() / 8;
std::vector<SDValue> PICLoads;
unsigned iter;
MVT MemVT = LD->getMemoryVT();
if(ISD::isNON_EXTLoad(N)) {
for (iter=0; iter<NumLoads ; ++iter) {
// Add the pointer offset if any
Offset = DAG.getConstant(iter + LoadOffset, MVT::i8);
Tys = DAG.getVTList(MVT::i8, MVT::Other);
Load = DAG.getNode(PIC16ISD::PIC16Load, Tys, Chain, PtrLo, PtrHi,
Offset);
PICLoads.push_back(Load);
}
} else {
// If it is extended load then use PIC16Load for Memory Bytes
// and for all extended bytes perform action based on type of
// extention - i.e. SignExtendedLoad or ZeroExtendedLoad
// For extended loads this is the memory value type
// i.e. without any extension
MVT MemVT = LD->getMemoryVT();
unsigned MemBytes = MemVT.getSizeInBits() / 8;
unsigned ExtdBytes = VT.getSizeInBits() / 8;
Offset = DAG.getConstant(LoadOffset, MVT::i8);
Tys = DAG.getVTList(MVT::i8, MVT::Other);
// For MemBytes generate PIC16Load with proper offset
for (iter=0; iter<MemBytes; ++iter) {
// Add the pointer offset if any
Offset = DAG.getConstant(iter + LoadOffset, MVT::i8);
Load = DAG.getNode(PIC16ISD::PIC16Load, Tys, Chain, PtrLo, PtrHi,
Offset);
PICLoads.push_back(Load);
}
// For SignExtendedLoad
if (ISD::isSEXTLoad(N)) {
// For all ExtdBytes use the Right Shifted(Arithmetic) Value of the
// highest MemByte
SDValue SRA = DAG.getNode(ISD::SRA, MVT::i8, Load,
DAG.getConstant(7, MVT::i8));
for (iter=MemBytes; iter<ExtdBytes; ++iter) {
PICLoads.push_back(SRA);
}
} else if (ISD::isZEXTLoad(N)) {
// ZeroExtendedLoad -- For all ExtdBytes use constant 0
SDValue ConstZero = DAG.getConstant(0, MVT::i8);
for (iter=MemBytes; iter<ExtdBytes; ++iter) {
PICLoads.push_back(ConstZero);
}
}
}
SDValue BP;
if (VT == MVT::i8) {
// Operand of Load is illegal -- Load itself is legal
return PICLoads[0].getNode();
}
else if (VT == MVT::i16) {
BP = DAG.getNode(ISD::BUILD_PAIR, VT, PICLoads[0], PICLoads[1]);
if (MemVT == MVT::i8)
Chain = getChain(PICLoads[0]);
else
Chain = DAG.getNode(ISD::TokenFactor, MVT::Other, getChain(PICLoads[0]),
getChain(PICLoads[1]));
} else if (VT == MVT::i32) {
SDValue BPs[2];
BPs[0] = DAG.getNode(ISD::BUILD_PAIR, MVT::i16, PICLoads[0], PICLoads[1]);
BPs[1] = DAG.getNode(ISD::BUILD_PAIR, MVT::i16, PICLoads[2], PICLoads[3]);
BP = DAG.getNode(ISD::BUILD_PAIR, VT, BPs[0], BPs[1]);
if (MemVT == MVT::i8)
Chain = getChain(PICLoads[0]);
else if (MemVT == MVT::i16)
Chain = DAG.getNode(ISD::TokenFactor, MVT::Other, getChain(PICLoads[0]),
getChain(PICLoads[1]));
else {
SDValue Chains[2];
Chains[0] = DAG.getNode(ISD::TokenFactor, MVT::Other,
getChain(PICLoads[0]), getChain(PICLoads[1]));
Chains[1] = DAG.getNode(ISD::TokenFactor, MVT::Other,
getChain(PICLoads[2]), getChain(PICLoads[3]));
Chain = DAG.getNode(ISD::TokenFactor, MVT::Other, Chains[0], Chains[1]);
}
}
Tys = DAG.getVTList(VT, MVT::Other);
SDValue MergeV = DAG.getNode(ISD::MERGE_VALUES, Tys, BP, Chain);
return MergeV.getNode();
}
SDNode *PIC16TargetLowering::ExpandShift(SDNode *N, SelectionDAG &DAG) {
SDValue Value = N->getOperand(0);
SDValue Amt = N->getOperand(1);
SDValue BCF, BCFInput;
SDVTList Tys;
SDValue ShfCom; // Shift Component - Lo component should be shifted
SDValue RotCom; // Rotate Component- Hi component should be rotated
PIC16ISD::NodeType ShfNode, RotNode;
// Currently handling Constant shift only
if (Amt.getOpcode() != ISD::Constant)
return NULL;
// Following code considers 16 bit left-shift only
if (N->getValueType(0) != MVT::i16)
return NULL;
if (N->getOpcode() == ISD::SHL) {
ShfNode = PIC16ISD::LSLF;
RotNode = PIC16ISD::RLF;
} else if (N->getOpcode() == ISD::SRL) {
ShfNode = PIC16ISD::LRLF;
RotNode = PIC16ISD::RRF;
}
unsigned ShiftAmt = dyn_cast<ConstantSDNode>(Amt)->getZExtValue();
SDValue StatusReg = DAG.getRegister(PIC16::STATUS, MVT::i8);
// 0th Bit in StatusReg is CarryBit
SDValue CarryBit= DAG.getConstant(0, MVT::i8);
GetExpandedParts(Value, DAG, ShfCom, RotCom);
BCFInput = DAG.getNode(PIC16ISD::Dummy, MVT::Flag);
Tys = DAG.getVTList(MVT::i8, MVT::Flag);
for (unsigned i=0;i<ShiftAmt;i++) {
BCF = DAG.getNode(PIC16ISD::BCF, MVT::Flag, StatusReg, CarryBit, BCFInput);
// Following are Two-Address Instructions
ShfCom = DAG.getNode(ShfNode, Tys, ShfCom, BCF);
RotCom = DAG.getNode(RotNode, Tys, RotCom, ShfCom.getValue(1));
BCFInput = RotCom.getValue(1);
}
SDValue BP = DAG.getNode(ISD::BUILD_PAIR, N->getValueType(0), ShfCom, RotCom);
return BP.getNode();
}
SDValue PIC16TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) {
switch (Op.getOpcode()) {
case ISD::FORMAL_ARGUMENTS:
return LowerFORMAL_ARGUMENTS(Op, DAG);
case ISD::ADDC:
return LowerADDC(Op, DAG);
case ISD::ADDE:
return LowerADDE(Op, DAG);
case ISD::SUBE:
return LowerSUBE(Op, DAG);
case ISD::SUBC:
return LowerSUBC(Op, DAG);
case ISD::LOAD:
return SDValue(ExpandLoad(Op.getNode(), DAG), Op.getResNo());
case ISD::STORE:
return SDValue(ExpandStore(Op.getNode(), DAG), Op.getResNo());
case ISD::SHL:
return SDValue(ExpandShift(Op.getNode(), DAG), Op.getResNo());
}
return SDValue();
}
SDValue PIC16TargetLowering::ConvertToMemOperand(SDValue Op,
SelectionDAG &DAG) {
assert (Op.getValueType() == MVT::i8
&& "illegal value type to store on stack.");
MachineFunction &MF = DAG.getMachineFunction();
const Function *Func = MF.getFunction();
const std::string FuncName = Func->getName();
char *tmpName = new char [strlen(FuncName.c_str()) + 6];
// Put the value on stack.
// Get a stack slot index and convert to es.
int FI = MF.getFrameInfo()->CreateStackObject(1, 1);
sprintf(tmpName, "%s.tmp", FuncName.c_str());
SDValue ES = DAG.getTargetExternalSymbol(tmpName, MVT::i8);
// Store the value to ES.
SDValue Store = DAG.getNode (PIC16ISD::PIC16Store, MVT::Other,
DAG.getEntryNode(),
Op, ES,
DAG.getConstant (1, MVT::i8), // Banksel.
DAG.getConstant (FI, MVT::i8));
// Load the value from ES.
SDVTList Tys = DAG.getVTList(MVT::i8, MVT::Other);
SDValue Load = DAG.getNode(PIC16ISD::PIC16Load, Tys, Store,
ES, DAG.getConstant (1, MVT::i8),
DAG.getConstant (FI, MVT::i8));
return Load.getValue(0);
}
SDValue PIC16TargetLowering:: LowerADDC(SDValue Op, SelectionDAG &DAG) {
// We should have handled larger operands in type legalizer itself.
assert (Op.getValueType() == MVT::i8 && "illegal addc to lower");
// Nothing to do if the one of the operands is already a load.
if (Op.getOperand(0).getOpcode() == PIC16ISD::PIC16Load
|| Op.getOperand(1).getOpcode() == PIC16ISD::PIC16Load)
return SDValue();
// Put one value on stack.
SDValue NewVal = ConvertToMemOperand (Op.getOperand(1), DAG);
SDVTList Tys = DAG.getVTList(MVT::i8, MVT::Flag);
return DAG.getNode(ISD::ADDC, Tys, Op.getOperand(0), NewVal);
}
SDValue PIC16TargetLowering:: LowerADDE(SDValue Op, SelectionDAG &DAG) {
// We should have handled larger operands in type legalizer itself.
assert (Op.getValueType() == MVT::i8 && "illegal adde to lower");
// Nothing to do if the one of the operands is already a load.
if (Op.getOperand(0).getOpcode() == PIC16ISD::PIC16Load
|| Op.getOperand(1).getOpcode() == PIC16ISD::PIC16Load)
return SDValue();
// Put one value on stack.
SDValue NewVal = ConvertToMemOperand (Op.getOperand(1), DAG);
SDVTList Tys = DAG.getVTList(MVT::i8, MVT::Flag);
return DAG.getNode(ISD::ADDE, Tys, Op.getOperand(0), NewVal,
Op.getOperand(2));
}
SDValue PIC16TargetLowering:: LowerSUBC(SDValue Op, SelectionDAG &DAG) {
// We should have handled larger operands in type legalizer itself.
assert (Op.getValueType() == MVT::i8 && "illegal subc to lower");
// Nothing to do if the first operand is already a load.
if (Op.getOperand(0).getOpcode() == PIC16ISD::PIC16Load)
return SDValue();
// Put first operand on stack.
SDValue NewVal = ConvertToMemOperand (Op.getOperand(0), DAG);
SDVTList Tys = DAG.getVTList(MVT::i8, MVT::Flag);
return DAG.getNode(ISD::SUBC, Tys, NewVal, Op.getOperand(1));
}
SDValue PIC16TargetLowering:: LowerSUBE(SDValue Op, SelectionDAG &DAG) {
// We should have handled larger operands in type legalizer itself.
assert (Op.getValueType() == MVT::i8 && "illegal sube to lower");
// Nothing to do if the first operand is already a load.
if (Op.getOperand(0).getOpcode() == PIC16ISD::PIC16Load)
return SDValue();
// Put first operand on stack.
SDValue NewVal = ConvertToMemOperand (Op.getOperand(0), DAG);
SDVTList Tys = DAG.getVTList(MVT::i8, MVT::Flag);
return DAG.getNode(ISD::SUBE, Tys, NewVal, Op.getOperand(1),
Op.getOperand(2));
}
// LowerFORMAL_ARGUMENTS - In Lowering FORMAL ARGUMENTS - MERGE_VALUES nodes
// is returned. MERGE_VALUES nodes number of operands and number of values are
// equal. Therefore to construct MERGE_VALUE node, UNDEF nodes equal to the
// number of arguments of function have been created.
SDValue PIC16TargetLowering:: LowerFORMAL_ARGUMENTS(SDValue Op,
SelectionDAG &DAG) {
SmallVector<SDValue, 8> ArgValues;
unsigned NumArgs = Op.getNumOperands() - 3;
// Creating UNDEF nodes to meet the requirement of MERGE_VALUES node.
for(unsigned i = 0 ; i<NumArgs ; i++) {
SDValue TempNode = DAG.getNode(ISD::UNDEF, Op.getNode()->getValueType(i));
ArgValues.push_back(TempNode);
}
ArgValues.push_back(Op.getOperand(0));
return DAG.getNode(ISD::MERGE_VALUES, Op.getNode()->getVTList(),
&ArgValues[0],
ArgValues.size()).getValue(Op.getResNo());
}
// Perform DAGCombine of PIC16Load
SDValue PIC16TargetLowering::
PerformPIC16LoadCombine(SDNode *N, DAGCombinerInfo &DCI) const {
SelectionDAG &DAG = DCI.DAG;
SDValue Chain = N->getOperand(0);
if (N->hasNUsesOfValue(0, 0)) {
DAG.ReplaceAllUsesOfValueWith(SDValue(N,1), Chain);
}
return SDValue();
}
SDValue PIC16TargetLowering::PerformDAGCombine(SDNode *N,
DAGCombinerInfo &DCI) const {
switch (N->getOpcode()) {
case PIC16ISD::PIC16Load:
return PerformPIC16LoadCombine(N, DCI);
}
return SDValue();
}