llvm-6502/lib/Target/Alpha/AlphaISelLowering.cpp
Andrew Lenharth 4e62951282 Let's see if we can break things.
Lower GOT relative addresses to Lo and HI.
Update both ISels to select them when they can.
Saves instructions here and there.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25001 91177308-0d34-0410-b5e6-96231b3b80d8
2005-12-24 05:36:33 +00:00

469 lines
18 KiB
C++

//===-- AlphaISelLowering.cpp - Alpha DAG Lowering Implementation ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Andrew Lenharth and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the AlphaISelLowering class.
//
//===----------------------------------------------------------------------===//
#include "AlphaISelLowering.h"
#include "AlphaTargetMachine.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/SSARegMap.h"
#include "llvm/Constants.h"
#include "llvm/Function.h"
#include "llvm/Support/CommandLine.h"
#include <iostream>
using namespace llvm;
namespace llvm {
extern cl::opt<bool> EnableAlphaIDIV;
extern cl::opt<bool> EnableAlphaCount;
extern cl::opt<bool> EnableAlphaLSMark;
}
/// AddLiveIn - This helper function adds the specified physical register to the
/// MachineFunction as a live in value. It also creates a corresponding virtual
/// register for it.
static unsigned AddLiveIn(MachineFunction &MF, unsigned PReg,
TargetRegisterClass *RC) {
assert(RC->contains(PReg) && "Not the correct regclass!");
unsigned VReg = MF.getSSARegMap()->createVirtualRegister(RC);
MF.addLiveIn(PReg, VReg);
return VReg;
}
AlphaTargetLowering::AlphaTargetLowering(TargetMachine &TM) : TargetLowering(TM) {
// Set up the TargetLowering object.
//I am having problems with shr n ubyte 1
setShiftAmountType(MVT::i64);
setSetCCResultType(MVT::i64);
setSetCCResultContents(ZeroOrOneSetCCResult);
addRegisterClass(MVT::i64, Alpha::GPRCRegisterClass);
addRegisterClass(MVT::f64, Alpha::F8RCRegisterClass);
addRegisterClass(MVT::f32, Alpha::F4RCRegisterClass);
setOperationAction(ISD::BRCONDTWOWAY, MVT::Other, Expand);
setOperationAction(ISD::BRTWOWAY_CC, MVT::Other, Expand);
setOperationAction(ISD::EXTLOAD, MVT::i1, Promote);
setOperationAction(ISD::EXTLOAD, MVT::f32, Expand);
setOperationAction(ISD::ZEXTLOAD, MVT::i1, Promote);
setOperationAction(ISD::ZEXTLOAD, MVT::i32, Expand);
setOperationAction(ISD::SEXTLOAD, MVT::i1, Promote);
setOperationAction(ISD::SEXTLOAD, MVT::i8, Expand);
setOperationAction(ISD::SEXTLOAD, MVT::i16, Expand);
setOperationAction(ISD::TRUNCSTORE, MVT::i1, Promote);
setOperationAction(ISD::FREM, MVT::f32, Expand);
setOperationAction(ISD::FREM, MVT::f64, Expand);
setOperationAction(ISD::UINT_TO_FP, MVT::i64, Expand);
setOperationAction(ISD::SINT_TO_FP, MVT::i64, Custom);
setOperationAction(ISD::FP_TO_UINT, MVT::i64, Expand);
setOperationAction(ISD::FP_TO_SINT, MVT::i64, Custom);
if (!TM.getSubtarget<AlphaSubtarget>().hasCT()) {
setOperationAction(ISD::CTPOP , MVT::i64 , Expand);
setOperationAction(ISD::CTTZ , MVT::i64 , Expand);
setOperationAction(ISD::CTLZ , MVT::i64 , Expand);
}
//If this didn't legalize into a div....
// setOperationAction(ISD::SREM , MVT::i64, Expand);
// setOperationAction(ISD::UREM , MVT::i64, Expand);
setOperationAction(ISD::MEMMOVE , MVT::Other, Expand);
setOperationAction(ISD::MEMSET , MVT::Other, Expand);
setOperationAction(ISD::MEMCPY , MVT::Other, Expand);
// We don't support sin/cos/sqrt
setOperationAction(ISD::FSIN , MVT::f64, Expand);
setOperationAction(ISD::FCOS , MVT::f64, Expand);
setOperationAction(ISD::FSQRT, MVT::f64, Expand);
setOperationAction(ISD::FSIN , MVT::f32, Expand);
setOperationAction(ISD::FCOS , MVT::f32, Expand);
setOperationAction(ISD::FSQRT, MVT::f32, Expand);
setOperationAction(ISD::SETCC, MVT::f32, Promote);
// We don't have line number support yet.
setOperationAction(ISD::LOCATION, MVT::Other, Expand);
setOperationAction(ISD::DEBUG_LOC, MVT::Other, Expand);
// We want to legalize GlobalAddress and ConstantPool nodes into the
// appropriate instructions to materialize the address.
setOperationAction(ISD::GlobalAddress, MVT::i64, Custom);
setOperationAction(ISD::ConstantPool, MVT::i64, Custom);
addLegalFPImmediate(+0.0); //F31
addLegalFPImmediate(-0.0); //-F31
computeRegisterProperties();
useITOF = TM.getSubtarget<AlphaSubtarget>().hasF2I();
}
//http://www.cs.arizona.edu/computer.help/policy/DIGITAL_unix/AA-PY8AC-TET1_html/callCH3.html#BLOCK21
//For now, just use variable size stack frame format
//In a standard call, the first six items are passed in registers $16
//- $21 and/or registers $f16 - $f21. (See Section 4.1.2 for details
//of argument-to-register correspondence.) The remaining items are
//collected in a memory argument list that is a naturally aligned
//array of quadwords. In a standard call, this list, if present, must
//be passed at 0(SP).
//7 ... n 0(SP) ... (n-7)*8(SP)
// //#define FP $15
// //#define RA $26
// //#define PV $27
// //#define GP $29
// //#define SP $30
std::vector<SDOperand>
AlphaTargetLowering::LowerArguments(Function &F, SelectionDAG &DAG)
{
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo *MFI = MF.getFrameInfo();
MachineBasicBlock& BB = MF.front();
std::vector<SDOperand> ArgValues;
unsigned args_int[] = {
Alpha::R16, Alpha::R17, Alpha::R18, Alpha::R19, Alpha::R20, Alpha::R21};
unsigned args_float[] = {
Alpha::F16, Alpha::F17, Alpha::F18, Alpha::F19, Alpha::F20, Alpha::F21};
int count = 0;
GP = AddLiveIn(MF, Alpha::R29, getRegClassFor(MVT::i64));
RA = AddLiveIn(MF, Alpha::R26, getRegClassFor(MVT::i64));
for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E; ++I)
{
SDOperand argt;
if (count < 6) {
unsigned Vreg;
MVT::ValueType VT = getValueType(I->getType());
switch (VT) {
default:
std::cerr << "Unknown Type " << VT << "\n";
abort();
case MVT::f64:
case MVT::f32:
args_float[count] = AddLiveIn(MF, args_float[count], getRegClassFor(VT));
argt = DAG.getCopyFromReg(DAG.getRoot(), args_float[count], VT);
DAG.setRoot(argt.getValue(1));
break;
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
case MVT::i64:
args_int[count] = AddLiveIn(MF, args_int[count], getRegClassFor(MVT::i64));
argt = DAG.getCopyFromReg(DAG.getRoot(), args_int[count], MVT::i64);
DAG.setRoot(argt.getValue(1));
if (VT != MVT::i64) {
unsigned AssertOp =
I->getType()->isSigned() ? ISD::AssertSext : ISD::AssertZext;
argt = DAG.getNode(AssertOp, MVT::i64, argt,
DAG.getValueType(VT));
argt = DAG.getNode(ISD::TRUNCATE, VT, argt);
}
break;
}
} else { //more args
// Create the frame index object for this incoming parameter...
int FI = MFI->CreateFixedObject(8, 8 * (count - 6));
// Create the SelectionDAG nodes corresponding to a load
//from this parameter
SDOperand FIN = DAG.getFrameIndex(FI, MVT::i64);
argt = DAG.getLoad(getValueType(I->getType()),
DAG.getEntryNode(), FIN, DAG.getSrcValue(NULL));
}
++count;
ArgValues.push_back(argt);
}
// If the functions takes variable number of arguments, copy all regs to stack
if (F.isVarArg()) {
VarArgsOffset = count * 8;
std::vector<SDOperand> LS;
for (int i = 0; i < 6; ++i) {
if (MRegisterInfo::isPhysicalRegister(args_int[i]))
args_int[i] = AddLiveIn(MF, args_int[i], getRegClassFor(MVT::i64));
SDOperand argt = DAG.getCopyFromReg(DAG.getRoot(), args_int[i], MVT::i64);
int FI = MFI->CreateFixedObject(8, -8 * (6 - i));
if (i == 0) VarArgsBase = FI;
SDOperand SDFI = DAG.getFrameIndex(FI, MVT::i64);
LS.push_back(DAG.getNode(ISD::STORE, MVT::Other, DAG.getRoot(), argt,
SDFI, DAG.getSrcValue(NULL)));
if (MRegisterInfo::isPhysicalRegister(args_float[i]))
args_float[i] = AddLiveIn(MF, args_float[i], getRegClassFor(MVT::f64));
argt = DAG.getCopyFromReg(DAG.getRoot(), args_float[i], MVT::f64);
FI = MFI->CreateFixedObject(8, - 8 * (12 - i));
SDFI = DAG.getFrameIndex(FI, MVT::i64);
LS.push_back(DAG.getNode(ISD::STORE, MVT::Other, DAG.getRoot(), argt,
SDFI, DAG.getSrcValue(NULL)));
}
//Set up a token factor with all the stack traffic
DAG.setRoot(DAG.getNode(ISD::TokenFactor, MVT::Other, LS));
}
// Finally, inform the code generator which regs we return values in.
switch (getValueType(F.getReturnType())) {
default: assert(0 && "Unknown type!");
case MVT::isVoid: break;
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
case MVT::i64:
MF.addLiveOut(Alpha::R0);
break;
case MVT::f32:
case MVT::f64:
MF.addLiveOut(Alpha::F0);
break;
}
//return the arguments
return ArgValues;
}
std::pair<SDOperand, SDOperand>
AlphaTargetLowering::LowerCallTo(SDOperand Chain,
const Type *RetTy, bool isVarArg,
unsigned CallingConv, bool isTailCall,
SDOperand Callee, ArgListTy &Args,
SelectionDAG &DAG) {
int NumBytes = 0;
if (Args.size() > 6)
NumBytes = (Args.size() - 6) * 8;
Chain = DAG.getNode(ISD::CALLSEQ_START, MVT::Other, Chain,
DAG.getConstant(NumBytes, getPointerTy()));
std::vector<SDOperand> args_to_use;
for (unsigned i = 0, e = Args.size(); i != e; ++i)
{
switch (getValueType(Args[i].second)) {
default: assert(0 && "Unexpected ValueType for argument!");
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
// Promote the integer to 64 bits. If the input type is signed use a
// sign extend, otherwise use a zero extend.
if (Args[i].second->isSigned())
Args[i].first = DAG.getNode(ISD::SIGN_EXTEND, MVT::i64, Args[i].first);
else
Args[i].first = DAG.getNode(ISD::ZERO_EXTEND, MVT::i64, Args[i].first);
break;
case MVT::i64:
case MVT::f64:
case MVT::f32:
break;
}
args_to_use.push_back(Args[i].first);
}
std::vector<MVT::ValueType> RetVals;
MVT::ValueType RetTyVT = getValueType(RetTy);
MVT::ValueType ActualRetTyVT = RetTyVT;
if (RetTyVT >= MVT::i1 && RetTyVT <= MVT::i32)
ActualRetTyVT = MVT::i64;
if (RetTyVT != MVT::isVoid)
RetVals.push_back(ActualRetTyVT);
RetVals.push_back(MVT::Other);
SDOperand TheCall = SDOperand(DAG.getCall(RetVals,
Chain, Callee, args_to_use), 0);
Chain = TheCall.getValue(RetTyVT != MVT::isVoid);
Chain = DAG.getNode(ISD::CALLSEQ_END, MVT::Other, Chain,
DAG.getConstant(NumBytes, getPointerTy()));
SDOperand RetVal = TheCall;
if (RetTyVT != ActualRetTyVT) {
RetVal = DAG.getNode(RetTy->isSigned() ? ISD::AssertSext : ISD::AssertZext,
MVT::i64, RetVal, DAG.getValueType(RetTyVT));
RetVal = DAG.getNode(ISD::TRUNCATE, RetTyVT, RetVal);
}
return std::make_pair(RetVal, Chain);
}
SDOperand AlphaTargetLowering::LowerVAStart(SDOperand Chain, SDOperand VAListP,
Value *VAListV, SelectionDAG &DAG) {
// vastart stores the address of the VarArgsBase and VarArgsOffset
SDOperand FR = DAG.getFrameIndex(VarArgsBase, MVT::i64);
SDOperand S1 = DAG.getNode(ISD::STORE, MVT::Other, Chain, FR, VAListP,
DAG.getSrcValue(VAListV));
SDOperand SA2 = DAG.getNode(ISD::ADD, MVT::i64, VAListP,
DAG.getConstant(8, MVT::i64));
return DAG.getNode(ISD::TRUNCSTORE, MVT::Other, S1,
DAG.getConstant(VarArgsOffset, MVT::i64), SA2,
DAG.getSrcValue(VAListV, 8), DAG.getValueType(MVT::i32));
}
std::pair<SDOperand,SDOperand> AlphaTargetLowering::
LowerVAArg(SDOperand Chain, SDOperand VAListP, Value *VAListV,
const Type *ArgTy, SelectionDAG &DAG) {
SDOperand Base = DAG.getLoad(MVT::i64, Chain, VAListP,
DAG.getSrcValue(VAListV));
SDOperand Tmp = DAG.getNode(ISD::ADD, MVT::i64, VAListP,
DAG.getConstant(8, MVT::i64));
SDOperand Offset = DAG.getExtLoad(ISD::SEXTLOAD, MVT::i64, Base.getValue(1),
Tmp, DAG.getSrcValue(VAListV, 8), MVT::i32);
SDOperand DataPtr = DAG.getNode(ISD::ADD, MVT::i64, Base, Offset);
if (ArgTy->isFloatingPoint())
{
//if fp && Offset < 6*8, then subtract 6*8 from DataPtr
SDOperand FPDataPtr = DAG.getNode(ISD::SUB, MVT::i64, DataPtr,
DAG.getConstant(8*6, MVT::i64));
SDOperand CC = DAG.getSetCC(MVT::i64, Offset,
DAG.getConstant(8*6, MVT::i64), ISD::SETLT);
DataPtr = DAG.getNode(ISD::SELECT, MVT::i64, CC, FPDataPtr, DataPtr);
}
SDOperand Result;
if (ArgTy == Type::IntTy)
Result = DAG.getExtLoad(ISD::SEXTLOAD, MVT::i64, Offset.getValue(1),
DataPtr, DAG.getSrcValue(NULL), MVT::i32);
else if (ArgTy == Type::UIntTy)
Result = DAG.getExtLoad(ISD::ZEXTLOAD, MVT::i64, Offset.getValue(1),
DataPtr, DAG.getSrcValue(NULL), MVT::i32);
else
Result = DAG.getLoad(getValueType(ArgTy), Offset.getValue(1), DataPtr,
DAG.getSrcValue(NULL));
SDOperand NewOffset = DAG.getNode(ISD::ADD, MVT::i64, Offset,
DAG.getConstant(8, MVT::i64));
SDOperand Update = DAG.getNode(ISD::TRUNCSTORE, MVT::Other,
Result.getValue(1), NewOffset,
Tmp, DAG.getSrcValue(VAListV, 8),
DAG.getValueType(MVT::i32));
Result = DAG.getNode(ISD::TRUNCATE, getValueType(ArgTy), Result);
return std::make_pair(Result, Update);
}
SDOperand AlphaTargetLowering::
LowerVACopy(SDOperand Chain, SDOperand SrcP, Value *SrcV, SDOperand DestP,
Value *DestV, SelectionDAG &DAG) {
SDOperand Val = DAG.getLoad(getPointerTy(), Chain, SrcP,
DAG.getSrcValue(SrcV));
SDOperand Result = DAG.getNode(ISD::STORE, MVT::Other, Val.getValue(1),
Val, DestP, DAG.getSrcValue(DestV));
SDOperand NP = DAG.getNode(ISD::ADD, MVT::i64, SrcP,
DAG.getConstant(8, MVT::i64));
Val = DAG.getExtLoad(ISD::SEXTLOAD, MVT::i64, Result, NP,
DAG.getSrcValue(SrcV, 8), MVT::i32);
SDOperand NPD = DAG.getNode(ISD::ADD, MVT::i64, DestP,
DAG.getConstant(8, MVT::i64));
return DAG.getNode(ISD::TRUNCSTORE, MVT::Other, Val.getValue(1),
Val, NPD, DAG.getSrcValue(DestV, 8),
DAG.getValueType(MVT::i32));
}
void AlphaTargetLowering::restoreGP(MachineBasicBlock* BB)
{
BuildMI(BB, Alpha::BIS, 2, Alpha::R29).addReg(GP).addReg(GP);
}
void AlphaTargetLowering::restoreRA(MachineBasicBlock* BB)
{
BuildMI(BB, Alpha::BIS, 2, Alpha::R26).addReg(RA).addReg(RA);
}
/// LowerOperation - Provide custom lowering hooks for some operations.
///
SDOperand AlphaTargetLowering::LowerOperation(SDOperand Op, SelectionDAG &DAG) {
switch (Op.getOpcode()) {
default: assert(0 && "Wasn't expecting to be able to lower this!");
case ISD::SINT_TO_FP: {
assert(MVT::i64 == Op.getOperand(0).getValueType() &&
"Unhandled SINT_TO_FP type in custom expander!");
SDOperand LD;
bool isDouble = MVT::f64 == Op.getValueType();
if (useITOF) {
LD = DAG.getNode(AlphaISD::ITOFT_, MVT::f64, Op.getOperand(0));
} else {
int FrameIdx =
DAG.getMachineFunction().getFrameInfo()->CreateStackObject(8, 8);
SDOperand FI = DAG.getFrameIndex(FrameIdx, MVT::i64);
SDOperand ST = DAG.getNode(ISD::STORE, MVT::Other, DAG.getEntryNode(),
Op.getOperand(0), FI, DAG.getSrcValue(0));
LD = DAG.getLoad(MVT::f64, ST, FI, DAG.getSrcValue(0));
}
SDOperand FP = DAG.getNode(isDouble?AlphaISD::CVTQT_:AlphaISD::CVTQS_,
isDouble?MVT::f64:MVT::f32, LD);
return FP;
}
case ISD::FP_TO_SINT: {
bool isDouble = MVT::f64 == Op.getOperand(0).getValueType();
SDOperand src = Op.getOperand(0);
if (!isDouble) //Promote
src = DAG.getNode(ISD::FP_EXTEND, MVT::f64, src);
src = DAG.getNode(AlphaISD::CVTTQ_, MVT::f64, src);
if (useITOF) {
return DAG.getNode(AlphaISD::FTOIT_, MVT::i64, src);
} else {
int FrameIdx =
DAG.getMachineFunction().getFrameInfo()->CreateStackObject(8, 8);
SDOperand FI = DAG.getFrameIndex(FrameIdx, MVT::i64);
SDOperand ST = DAG.getNode(ISD::STORE, MVT::Other, DAG.getEntryNode(),
src, FI, DAG.getSrcValue(0));
return DAG.getLoad(MVT::i64, ST, FI, DAG.getSrcValue(0));
}
}
case ISD::ConstantPool: {
Constant *C = cast<ConstantPoolSDNode>(Op)->get();
SDOperand CPI = DAG.getTargetConstantPool(C, MVT::i64);
SDOperand Hi = DAG.getNode(AlphaISD::GPRelHi, MVT::i64, CPI,
DAG.getNode(AlphaISD::GlobalBaseReg, MVT::i64));
SDOperand Lo = DAG.getNode(AlphaISD::GPRelLo, MVT::i64, CPI, Hi);
return Lo;
}
case ISD::GlobalAddress: {
GlobalAddressSDNode *GSDN = cast<GlobalAddressSDNode>(Op);
GlobalValue *GV = GSDN->getGlobal();
SDOperand GA = DAG.getTargetGlobalAddress(GV, MVT::i64, GSDN->getOffset());
if (!GV->hasWeakLinkage() && !GV->isExternal()) {
SDOperand Hi = DAG.getNode(AlphaISD::GPRelHi, MVT::i64, GA,
DAG.getNode(AlphaISD::GlobalBaseReg, MVT::i64));
SDOperand Lo = DAG.getNode(AlphaISD::GPRelLo, MVT::i64, GA, Hi);
return Lo;
} else
return GA;
}
}
return SDOperand();
}