llvm-6502/lib/Target/Alpha/AlphaISelLowering.cpp
2005-09-04 06:12:19 +00:00

377 lines
14 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> EnableAlphaFTOI;
extern cl::opt<bool> EnableAlphaCT;
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::FPRCRegisterClass);
addRegisterClass(MVT::f32, Alpha::FPRCRegisterClass);
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::SREM, MVT::f32, Expand);
setOperationAction(ISD::SREM, MVT::f64, Expand);
setOperationAction(ISD::UINT_TO_FP, MVT::i64, Expand);
if (!EnableAlphaCT) {
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);
//Doesn't work yet
setOperationAction(ISD::SETCC, MVT::f32, Promote);
computeRegisterProperties();
addLegalFPImmediate(+0.0); //F31
addLegalFPImmediate(-0.0); //-F31
}
//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};
unsigned added_int = 0;
unsigned added_fp = 0;
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));
added_fp |= (1 << count);
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));
added_int |= (1 << count);
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 (!(added_int & (1 << 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 (!(added_fp & (1 << 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);
if (RetTyVT != MVT::isVoid)
RetVals.push_back(RetTyVT);
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()));
return std::make_pair(TheCall, 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);
}