llvm-6502/lib/Target/Sparc/SparcISelDAGToDAG.cpp
2006-10-13 21:14:26 +00:00

1122 lines
42 KiB
C++

//===-- SparcISelDAGToDAG.cpp - A dag to dag inst selector for Sparc ------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Chris Lattner and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines an instruction selector for the SPARC target.
//
//===----------------------------------------------------------------------===//
#include "Sparc.h"
#include "SparcTargetMachine.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/Intrinsics.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/SelectionDAGISel.h"
#include "llvm/CodeGen/SSARegMap.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Support/Debug.h"
#include <iostream>
#include <queue>
#include <set>
using namespace llvm;
//===----------------------------------------------------------------------===//
// TargetLowering Implementation
//===----------------------------------------------------------------------===//
namespace SPISD {
enum {
FIRST_NUMBER = ISD::BUILTIN_OP_END+SP::INSTRUCTION_LIST_END,
CMPICC, // Compare two GPR operands, set icc.
CMPFCC, // Compare two FP operands, set fcc.
BRICC, // Branch to dest on icc condition
BRFCC, // Branch to dest on fcc condition
SELECT_ICC, // Select between two values using the current ICC flags.
SELECT_FCC, // Select between two values using the current FCC flags.
Hi, Lo, // Hi/Lo operations, typically on a global address.
FTOI, // FP to Int within a FP register.
ITOF, // Int to FP within a FP register.
CALL, // A call instruction.
RET_FLAG // Return with a flag operand.
};
}
/// IntCondCCodeToICC - Convert a DAG integer condition code to a SPARC ICC
/// condition.
static SPCC::CondCodes IntCondCCodeToICC(ISD::CondCode CC) {
switch (CC) {
default: assert(0 && "Unknown integer condition code!");
case ISD::SETEQ: return SPCC::ICC_E;
case ISD::SETNE: return SPCC::ICC_NE;
case ISD::SETLT: return SPCC::ICC_L;
case ISD::SETGT: return SPCC::ICC_G;
case ISD::SETLE: return SPCC::ICC_LE;
case ISD::SETGE: return SPCC::ICC_GE;
case ISD::SETULT: return SPCC::ICC_CS;
case ISD::SETULE: return SPCC::ICC_LEU;
case ISD::SETUGT: return SPCC::ICC_GU;
case ISD::SETUGE: return SPCC::ICC_CC;
}
}
/// FPCondCCodeToFCC - Convert a DAG floatingp oint condition code to a SPARC
/// FCC condition.
static SPCC::CondCodes FPCondCCodeToFCC(ISD::CondCode CC) {
switch (CC) {
default: assert(0 && "Unknown fp condition code!");
case ISD::SETEQ:
case ISD::SETOEQ: return SPCC::FCC_E;
case ISD::SETNE:
case ISD::SETUNE: return SPCC::FCC_NE;
case ISD::SETLT:
case ISD::SETOLT: return SPCC::FCC_L;
case ISD::SETGT:
case ISD::SETOGT: return SPCC::FCC_G;
case ISD::SETLE:
case ISD::SETOLE: return SPCC::FCC_LE;
case ISD::SETGE:
case ISD::SETOGE: return SPCC::FCC_GE;
case ISD::SETULT: return SPCC::FCC_UL;
case ISD::SETULE: return SPCC::FCC_ULE;
case ISD::SETUGT: return SPCC::FCC_UG;
case ISD::SETUGE: return SPCC::FCC_UGE;
case ISD::SETUO: return SPCC::FCC_U;
case ISD::SETO: return SPCC::FCC_O;
case ISD::SETONE: return SPCC::FCC_LG;
case ISD::SETUEQ: return SPCC::FCC_UE;
}
}
namespace {
class SparcTargetLowering : public TargetLowering {
int VarArgsFrameOffset; // Frame offset to start of varargs area.
public:
SparcTargetLowering(TargetMachine &TM);
virtual SDOperand LowerOperation(SDOperand Op, SelectionDAG &DAG);
/// computeMaskedBitsForTargetNode - Determine which of the bits specified
/// in Mask are known to be either zero or one and return them in the
/// KnownZero/KnownOne bitsets.
virtual void computeMaskedBitsForTargetNode(const SDOperand Op,
uint64_t Mask,
uint64_t &KnownZero,
uint64_t &KnownOne,
unsigned Depth = 0) const;
virtual std::vector<SDOperand>
LowerArguments(Function &F, SelectionDAG &DAG);
virtual std::pair<SDOperand, SDOperand>
LowerCallTo(SDOperand Chain, const Type *RetTy, bool isVarArg,
unsigned CC,
bool isTailCall, SDOperand Callee, ArgListTy &Args,
SelectionDAG &DAG);
virtual MachineBasicBlock *InsertAtEndOfBasicBlock(MachineInstr *MI,
MachineBasicBlock *MBB);
virtual const char *getTargetNodeName(unsigned Opcode) const;
};
}
SparcTargetLowering::SparcTargetLowering(TargetMachine &TM)
: TargetLowering(TM) {
// Set up the register classes.
addRegisterClass(MVT::i32, SP::IntRegsRegisterClass);
addRegisterClass(MVT::f32, SP::FPRegsRegisterClass);
addRegisterClass(MVT::f64, SP::DFPRegsRegisterClass);
// Turn FP extload into load/fextend
setLoadXAction(ISD::EXTLOAD, MVT::f32, Expand);
// Custom legalize GlobalAddress nodes into LO/HI parts.
setOperationAction(ISD::GlobalAddress, MVT::i32, Custom);
setOperationAction(ISD::ConstantPool , MVT::i32, Custom);
// Sparc doesn't have sext_inreg, replace them with shl/sra
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8 , Expand);
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1 , Expand);
// Sparc has no REM operation.
setOperationAction(ISD::UREM, MVT::i32, Expand);
setOperationAction(ISD::SREM, MVT::i32, Expand);
// Custom expand fp<->sint
setOperationAction(ISD::FP_TO_SINT, MVT::i32, Custom);
setOperationAction(ISD::SINT_TO_FP, MVT::i32, Custom);
// Expand fp<->uint
setOperationAction(ISD::FP_TO_UINT, MVT::i32, Expand);
setOperationAction(ISD::UINT_TO_FP, MVT::i32, Expand);
setOperationAction(ISD::BIT_CONVERT, MVT::f32, Expand);
setOperationAction(ISD::BIT_CONVERT, MVT::i32, Expand);
// Sparc has no select or setcc: expand to SELECT_CC.
setOperationAction(ISD::SELECT, MVT::i32, Expand);
setOperationAction(ISD::SELECT, MVT::f32, Expand);
setOperationAction(ISD::SELECT, MVT::f64, Expand);
setOperationAction(ISD::SETCC, MVT::i32, Expand);
setOperationAction(ISD::SETCC, MVT::f32, Expand);
setOperationAction(ISD::SETCC, MVT::f64, Expand);
// Sparc doesn't have BRCOND either, it has BR_CC.
setOperationAction(ISD::BRCOND, MVT::Other, Expand);
setOperationAction(ISD::BRIND, MVT::i32, Expand);
setOperationAction(ISD::BR_CC, MVT::i32, Custom);
setOperationAction(ISD::BR_CC, MVT::f32, Custom);
setOperationAction(ISD::BR_CC, MVT::f64, Custom);
setOperationAction(ISD::SELECT_CC, MVT::i32, Custom);
setOperationAction(ISD::SELECT_CC, MVT::f32, Custom);
setOperationAction(ISD::SELECT_CC, MVT::f64, Custom);
// SPARC has no intrinsics for these particular operations.
setOperationAction(ISD::MEMMOVE, MVT::Other, Expand);
setOperationAction(ISD::MEMSET, MVT::Other, Expand);
setOperationAction(ISD::MEMCPY, MVT::Other, Expand);
setOperationAction(ISD::FSIN , MVT::f64, Expand);
setOperationAction(ISD::FCOS , MVT::f64, Expand);
setOperationAction(ISD::FSIN , MVT::f32, Expand);
setOperationAction(ISD::FCOS , MVT::f32, Expand);
setOperationAction(ISD::CTPOP, MVT::i32, Expand);
setOperationAction(ISD::CTTZ , MVT::i32, Expand);
setOperationAction(ISD::CTLZ , MVT::i32, Expand);
setOperationAction(ISD::ROTL , MVT::i32, Expand);
setOperationAction(ISD::ROTR , MVT::i32, Expand);
setOperationAction(ISD::BSWAP, MVT::i32, Expand);
setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
setOperationAction(ISD::SHL_PARTS, MVT::i32, Expand);
setOperationAction(ISD::SRA_PARTS, MVT::i32, Expand);
setOperationAction(ISD::SRL_PARTS, MVT::i32, Expand);
// We don't have line number support yet.
setOperationAction(ISD::LOCATION, MVT::Other, Expand);
setOperationAction(ISD::DEBUG_LOC, MVT::Other, Expand);
setOperationAction(ISD::DEBUG_LABEL, MVT::Other, Expand);
// RET must be custom lowered, to meet ABI requirements
setOperationAction(ISD::RET , MVT::Other, Custom);
// VASTART needs to be custom lowered to use the VarArgsFrameIndex.
setOperationAction(ISD::VASTART , MVT::Other, Custom);
// VAARG needs to be lowered to not do unaligned accesses for doubles.
setOperationAction(ISD::VAARG , MVT::Other, Custom);
// Use the default implementation.
setOperationAction(ISD::VACOPY , MVT::Other, Expand);
setOperationAction(ISD::VAEND , MVT::Other, Expand);
setOperationAction(ISD::STACKSAVE , MVT::Other, Expand);
setOperationAction(ISD::STACKRESTORE , MVT::Other, Expand);
setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32 , Custom);
setOperationAction(ISD::ConstantFP, MVT::f64, Expand);
setOperationAction(ISD::ConstantFP, MVT::f32, Expand);
setStackPointerRegisterToSaveRestore(SP::O6);
if (TM.getSubtarget<SparcSubtarget>().isV9()) {
setOperationAction(ISD::CTPOP, MVT::i32, Legal);
}
computeRegisterProperties();
}
const char *SparcTargetLowering::getTargetNodeName(unsigned Opcode) const {
switch (Opcode) {
default: return 0;
case SPISD::CMPICC: return "SPISD::CMPICC";
case SPISD::CMPFCC: return "SPISD::CMPFCC";
case SPISD::BRICC: return "SPISD::BRICC";
case SPISD::BRFCC: return "SPISD::BRFCC";
case SPISD::SELECT_ICC: return "SPISD::SELECT_ICC";
case SPISD::SELECT_FCC: return "SPISD::SELECT_FCC";
case SPISD::Hi: return "SPISD::Hi";
case SPISD::Lo: return "SPISD::Lo";
case SPISD::FTOI: return "SPISD::FTOI";
case SPISD::ITOF: return "SPISD::ITOF";
case SPISD::CALL: return "SPISD::CALL";
case SPISD::RET_FLAG: return "SPISD::RET_FLAG";
}
}
/// isMaskedValueZeroForTargetNode - Return true if 'Op & Mask' is known to
/// be zero. Op is expected to be a target specific node. Used by DAG
/// combiner.
void SparcTargetLowering::computeMaskedBitsForTargetNode(const SDOperand Op,
uint64_t Mask,
uint64_t &KnownZero,
uint64_t &KnownOne,
unsigned Depth) const {
uint64_t KnownZero2, KnownOne2;
KnownZero = KnownOne = 0; // Don't know anything.
switch (Op.getOpcode()) {
default: break;
case SPISD::SELECT_ICC:
case SPISD::SELECT_FCC:
ComputeMaskedBits(Op.getOperand(1), Mask, KnownZero, KnownOne, Depth+1);
ComputeMaskedBits(Op.getOperand(0), Mask, KnownZero2, KnownOne2, Depth+1);
assert((KnownZero & KnownOne) == 0 && "Bits known to be one AND zero?");
assert((KnownZero2 & KnownOne2) == 0 && "Bits known to be one AND zero?");
// Only known if known in both the LHS and RHS.
KnownOne &= KnownOne2;
KnownZero &= KnownZero2;
break;
}
}
/// LowerArguments - V8 uses a very simple ABI, where all values are passed in
/// either one or two GPRs, including FP values. TODO: we should pass FP values
/// in FP registers for fastcc functions.
std::vector<SDOperand>
SparcTargetLowering::LowerArguments(Function &F, SelectionDAG &DAG) {
MachineFunction &MF = DAG.getMachineFunction();
SSARegMap *RegMap = MF.getSSARegMap();
std::vector<SDOperand> ArgValues;
static const unsigned ArgRegs[] = {
SP::I0, SP::I1, SP::I2, SP::I3, SP::I4, SP::I5
};
const unsigned *CurArgReg = ArgRegs, *ArgRegEnd = ArgRegs+6;
unsigned ArgOffset = 68;
SDOperand Root = DAG.getRoot();
std::vector<SDOperand> OutChains;
for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E; ++I) {
MVT::ValueType ObjectVT = getValueType(I->getType());
switch (ObjectVT) {
default: assert(0 && "Unhandled argument type!");
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
if (I->use_empty()) { // Argument is dead.
if (CurArgReg < ArgRegEnd) ++CurArgReg;
ArgValues.push_back(DAG.getNode(ISD::UNDEF, ObjectVT));
} else if (CurArgReg < ArgRegEnd) { // Lives in an incoming GPR
unsigned VReg = RegMap->createVirtualRegister(&SP::IntRegsRegClass);
MF.addLiveIn(*CurArgReg++, VReg);
SDOperand Arg = DAG.getCopyFromReg(Root, VReg, MVT::i32);
if (ObjectVT != MVT::i32) {
unsigned AssertOp = I->getType()->isSigned() ? ISD::AssertSext
: ISD::AssertZext;
Arg = DAG.getNode(AssertOp, MVT::i32, Arg,
DAG.getValueType(ObjectVT));
Arg = DAG.getNode(ISD::TRUNCATE, ObjectVT, Arg);
}
ArgValues.push_back(Arg);
} else {
int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
SDOperand FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
SDOperand Load;
if (ObjectVT == MVT::i32) {
Load = DAG.getLoad(MVT::i32, Root, FIPtr, NULL, 0);
} else {
ISD::LoadExtType LoadOp =
I->getType()->isSigned() ? ISD::SEXTLOAD : ISD::ZEXTLOAD;
// Sparc is big endian, so add an offset based on the ObjectVT.
unsigned Offset = 4-std::max(1U, MVT::getSizeInBits(ObjectVT)/8);
FIPtr = DAG.getNode(ISD::ADD, MVT::i32, FIPtr,
DAG.getConstant(Offset, MVT::i32));
Load = DAG.getExtLoad(LoadOp, MVT::i32, Root, FIPtr,
NULL, 0, ObjectVT);
Load = DAG.getNode(ISD::TRUNCATE, ObjectVT, Load);
}
ArgValues.push_back(Load);
}
ArgOffset += 4;
break;
case MVT::f32:
if (I->use_empty()) { // Argument is dead.
if (CurArgReg < ArgRegEnd) ++CurArgReg;
ArgValues.push_back(DAG.getNode(ISD::UNDEF, ObjectVT));
} else if (CurArgReg < ArgRegEnd) { // Lives in an incoming GPR
// FP value is passed in an integer register.
unsigned VReg = RegMap->createVirtualRegister(&SP::IntRegsRegClass);
MF.addLiveIn(*CurArgReg++, VReg);
SDOperand Arg = DAG.getCopyFromReg(Root, VReg, MVT::i32);
Arg = DAG.getNode(ISD::BIT_CONVERT, MVT::f32, Arg);
ArgValues.push_back(Arg);
} else {
int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
SDOperand FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
SDOperand Load = DAG.getLoad(MVT::f32, Root, FIPtr, NULL, 0);
ArgValues.push_back(Load);
}
ArgOffset += 4;
break;
case MVT::i64:
case MVT::f64:
if (I->use_empty()) { // Argument is dead.
if (CurArgReg < ArgRegEnd) ++CurArgReg;
if (CurArgReg < ArgRegEnd) ++CurArgReg;
ArgValues.push_back(DAG.getNode(ISD::UNDEF, ObjectVT));
} else if (/* FIXME: Apparently this isn't safe?? */
0 && CurArgReg == ArgRegEnd && ObjectVT == MVT::f64 &&
((CurArgReg-ArgRegs) & 1) == 0) {
// If this is a double argument and the whole thing lives on the stack,
// and the argument is aligned, load the double straight from the stack.
// We can't do a load in cases like void foo([6ints], int,double),
// because the double wouldn't be aligned!
int FrameIdx = MF.getFrameInfo()->CreateFixedObject(8, ArgOffset);
SDOperand FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
ArgValues.push_back(DAG.getLoad(MVT::f64, Root, FIPtr, NULL, 0));
} else {
SDOperand HiVal;
if (CurArgReg < ArgRegEnd) { // Lives in an incoming GPR
unsigned VRegHi = RegMap->createVirtualRegister(&SP::IntRegsRegClass);
MF.addLiveIn(*CurArgReg++, VRegHi);
HiVal = DAG.getCopyFromReg(Root, VRegHi, MVT::i32);
} else {
int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
SDOperand FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
HiVal = DAG.getLoad(MVT::i32, Root, FIPtr, NULL, 0);
}
SDOperand LoVal;
if (CurArgReg < ArgRegEnd) { // Lives in an incoming GPR
unsigned VRegLo = RegMap->createVirtualRegister(&SP::IntRegsRegClass);
MF.addLiveIn(*CurArgReg++, VRegLo);
LoVal = DAG.getCopyFromReg(Root, VRegLo, MVT::i32);
} else {
int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset+4);
SDOperand FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
LoVal = DAG.getLoad(MVT::i32, Root, FIPtr, NULL, 0);
}
// Compose the two halves together into an i64 unit.
SDOperand WholeValue =
DAG.getNode(ISD::BUILD_PAIR, MVT::i64, LoVal, HiVal);
// If we want a double, do a bit convert.
if (ObjectVT == MVT::f64)
WholeValue = DAG.getNode(ISD::BIT_CONVERT, MVT::f64, WholeValue);
ArgValues.push_back(WholeValue);
}
ArgOffset += 8;
break;
}
}
// Store remaining ArgRegs to the stack if this is a varargs function.
if (F.getFunctionType()->isVarArg()) {
// Remember the vararg offset for the va_start implementation.
VarArgsFrameOffset = ArgOffset;
for (; CurArgReg != ArgRegEnd; ++CurArgReg) {
unsigned VReg = RegMap->createVirtualRegister(&SP::IntRegsRegClass);
MF.addLiveIn(*CurArgReg, VReg);
SDOperand Arg = DAG.getCopyFromReg(DAG.getRoot(), VReg, MVT::i32);
int FrameIdx = MF.getFrameInfo()->CreateFixedObject(4, ArgOffset);
SDOperand FIPtr = DAG.getFrameIndex(FrameIdx, MVT::i32);
OutChains.push_back(DAG.getStore(DAG.getRoot(), Arg, FIPtr, NULL, 0));
ArgOffset += 4;
}
}
if (!OutChains.empty())
DAG.setRoot(DAG.getNode(ISD::TokenFactor, MVT::Other,
&OutChains[0], OutChains.size()));
// 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:
MF.addLiveOut(SP::I0);
break;
case MVT::i64:
MF.addLiveOut(SP::I0);
MF.addLiveOut(SP::I1);
break;
case MVT::f32:
MF.addLiveOut(SP::F0);
break;
case MVT::f64:
MF.addLiveOut(SP::D0);
break;
}
return ArgValues;
}
std::pair<SDOperand, SDOperand>
SparcTargetLowering::LowerCallTo(SDOperand Chain, const Type *RetTy,
bool isVarArg, unsigned CC,
bool isTailCall, SDOperand Callee,
ArgListTy &Args, SelectionDAG &DAG) {
// Count the size of the outgoing arguments.
unsigned ArgsSize = 0;
for (unsigned i = 0, e = Args.size(); i != e; ++i) {
switch (getValueType(Args[i].second)) {
default: assert(0 && "Unknown value type!");
case MVT::i1:
case MVT::i8:
case MVT::i16:
case MVT::i32:
case MVT::f32:
ArgsSize += 4;
break;
case MVT::i64:
case MVT::f64:
ArgsSize += 8;
break;
}
}
if (ArgsSize > 4*6)
ArgsSize -= 4*6; // Space for first 6 arguments is prereserved.
else
ArgsSize = 0;
// Keep stack frames 8-byte aligned.
ArgsSize = (ArgsSize+7) & ~7;
Chain = DAG.getCALLSEQ_START(Chain,DAG.getConstant(ArgsSize, getPointerTy()));
SDOperand StackPtr;
std::vector<SDOperand> Stores;
std::vector<SDOperand> RegValuesToPass;
unsigned ArgOffset = 68;
for (unsigned i = 0, e = Args.size(); i != e; ++i) {
SDOperand Val = Args[i].first;
MVT::ValueType ObjectVT = Val.getValueType();
SDOperand ValToStore(0, 0);
unsigned ObjSize;
switch (ObjectVT) {
default: assert(0 && "Unhandled argument type!");
case MVT::i1:
case MVT::i8:
case MVT::i16:
// Promote the integer to 32-bits. If the input type is signed, use a
// sign extend, otherwise use a zero extend.
if (Args[i].second->isSigned())
Val = DAG.getNode(ISD::SIGN_EXTEND, MVT::i32, Val);
else
Val = DAG.getNode(ISD::ZERO_EXTEND, MVT::i32, Val);
// FALL THROUGH
case MVT::i32:
ObjSize = 4;
if (RegValuesToPass.size() >= 6) {
ValToStore = Val;
} else {
RegValuesToPass.push_back(Val);
}
break;
case MVT::f32:
ObjSize = 4;
if (RegValuesToPass.size() >= 6) {
ValToStore = Val;
} else {
// Convert this to a FP value in an int reg.
Val = DAG.getNode(ISD::BIT_CONVERT, MVT::i32, Val);
RegValuesToPass.push_back(Val);
}
break;
case MVT::f64:
ObjSize = 8;
// If we can store this directly into the outgoing slot, do so. We can
// do this when all ArgRegs are used and if the outgoing slot is aligned.
// FIXME: McGill/misr fails with this.
if (0 && RegValuesToPass.size() >= 6 && ((ArgOffset-68) & 7) == 0) {
ValToStore = Val;
break;
}
// Otherwise, convert this to a FP value in int regs.
Val = DAG.getNode(ISD::BIT_CONVERT, MVT::i64, Val);
// FALL THROUGH
case MVT::i64:
ObjSize = 8;
if (RegValuesToPass.size() >= 6) {
ValToStore = Val; // Whole thing is passed in memory.
break;
}
// Split the value into top and bottom part. Top part goes in a reg.
SDOperand Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, getPointerTy(), Val,
DAG.getConstant(1, MVT::i32));
SDOperand Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, getPointerTy(), Val,
DAG.getConstant(0, MVT::i32));
RegValuesToPass.push_back(Hi);
if (RegValuesToPass.size() >= 6) {
ValToStore = Lo;
ArgOffset += 4;
ObjSize = 4;
} else {
RegValuesToPass.push_back(Lo);
}
break;
}
if (ValToStore.Val) {
if (!StackPtr.Val) {
StackPtr = DAG.getRegister(SP::O6, MVT::i32);
}
SDOperand PtrOff = DAG.getConstant(ArgOffset, getPointerTy());
PtrOff = DAG.getNode(ISD::ADD, MVT::i32, StackPtr, PtrOff);
Stores.push_back(DAG.getStore(Chain, ValToStore, PtrOff, NULL, 0));
}
ArgOffset += ObjSize;
}
// Emit all stores, make sure the occur before any copies into physregs.
if (!Stores.empty())
Chain = DAG.getNode(ISD::TokenFactor, MVT::Other, &Stores[0],Stores.size());
static const unsigned ArgRegs[] = {
SP::O0, SP::O1, SP::O2, SP::O3, SP::O4, SP::O5
};
// Build a sequence of copy-to-reg nodes chained together with token chain
// and flag operands which copy the outgoing args into O[0-5].
SDOperand InFlag;
for (unsigned i = 0, e = RegValuesToPass.size(); i != e; ++i) {
Chain = DAG.getCopyToReg(Chain, ArgRegs[i], RegValuesToPass[i], InFlag);
InFlag = Chain.getValue(1);
}
// If the callee is a GlobalAddress node (quite common, every direct call is)
// turn it into a TargetGlobalAddress node so that legalize doesn't hack it.
// Likewise ExternalSymbol -> TargetExternalSymbol.
if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
Callee = DAG.getTargetGlobalAddress(G->getGlobal(), MVT::i32);
else if (ExternalSymbolSDNode *E = dyn_cast<ExternalSymbolSDNode>(Callee))
Callee = DAG.getTargetExternalSymbol(E->getSymbol(), MVT::i32);
std::vector<MVT::ValueType> NodeTys;
NodeTys.push_back(MVT::Other); // Returns a chain
NodeTys.push_back(MVT::Flag); // Returns a flag for retval copy to use.
SDOperand Ops[] = { Chain, Callee, InFlag };
Chain = DAG.getNode(SPISD::CALL, NodeTys, Ops, InFlag.Val ? 3 : 2);
InFlag = Chain.getValue(1);
MVT::ValueType RetTyVT = getValueType(RetTy);
SDOperand RetVal;
if (RetTyVT != MVT::isVoid) {
switch (RetTyVT) {
default: assert(0 && "Unknown value type to return!");
case MVT::i1:
case MVT::i8:
case MVT::i16:
RetVal = DAG.getCopyFromReg(Chain, SP::O0, MVT::i32, InFlag);
Chain = RetVal.getValue(1);
// Add a note to keep track of whether it is sign or zero extended.
RetVal = DAG.getNode(RetTy->isSigned() ? ISD::AssertSext :ISD::AssertZext,
MVT::i32, RetVal, DAG.getValueType(RetTyVT));
RetVal = DAG.getNode(ISD::TRUNCATE, RetTyVT, RetVal);
break;
case MVT::i32:
RetVal = DAG.getCopyFromReg(Chain, SP::O0, MVT::i32, InFlag);
Chain = RetVal.getValue(1);
break;
case MVT::f32:
RetVal = DAG.getCopyFromReg(Chain, SP::F0, MVT::f32, InFlag);
Chain = RetVal.getValue(1);
break;
case MVT::f64:
RetVal = DAG.getCopyFromReg(Chain, SP::D0, MVT::f64, InFlag);
Chain = RetVal.getValue(1);
break;
case MVT::i64:
SDOperand Lo = DAG.getCopyFromReg(Chain, SP::O1, MVT::i32, InFlag);
SDOperand Hi = DAG.getCopyFromReg(Lo.getValue(1), SP::O0, MVT::i32,
Lo.getValue(2));
RetVal = DAG.getNode(ISD::BUILD_PAIR, MVT::i64, Lo, Hi);
Chain = Hi.getValue(1);
break;
}
}
Chain = DAG.getNode(ISD::CALLSEQ_END, MVT::Other, Chain,
DAG.getConstant(ArgsSize, getPointerTy()));
return std::make_pair(RetVal, Chain);
}
// Look at LHS/RHS/CC and see if they are a lowered setcc instruction. If so
// set LHS/RHS and SPCC to the LHS/RHS of the setcc and SPCC to the condition.
static void LookThroughSetCC(SDOperand &LHS, SDOperand &RHS,
ISD::CondCode CC, unsigned &SPCC) {
if (isa<ConstantSDNode>(RHS) && cast<ConstantSDNode>(RHS)->getValue() == 0 &&
CC == ISD::SETNE &&
((LHS.getOpcode() == SPISD::SELECT_ICC &&
LHS.getOperand(3).getOpcode() == SPISD::CMPICC) ||
(LHS.getOpcode() == SPISD::SELECT_FCC &&
LHS.getOperand(3).getOpcode() == SPISD::CMPFCC)) &&
isa<ConstantSDNode>(LHS.getOperand(0)) &&
isa<ConstantSDNode>(LHS.getOperand(1)) &&
cast<ConstantSDNode>(LHS.getOperand(0))->getValue() == 1 &&
cast<ConstantSDNode>(LHS.getOperand(1))->getValue() == 0) {
SDOperand CMPCC = LHS.getOperand(3);
SPCC = cast<ConstantSDNode>(LHS.getOperand(2))->getValue();
LHS = CMPCC.getOperand(0);
RHS = CMPCC.getOperand(1);
}
}
SDOperand SparcTargetLowering::
LowerOperation(SDOperand Op, SelectionDAG &DAG) {
switch (Op.getOpcode()) {
default: assert(0 && "Should not custom lower this!");
case ISD::GlobalAddress: {
GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
SDOperand GA = DAG.getTargetGlobalAddress(GV, MVT::i32);
SDOperand Hi = DAG.getNode(SPISD::Hi, MVT::i32, GA);
SDOperand Lo = DAG.getNode(SPISD::Lo, MVT::i32, GA);
return DAG.getNode(ISD::ADD, MVT::i32, Lo, Hi);
}
case ISD::ConstantPool: {
Constant *C = cast<ConstantPoolSDNode>(Op)->getConstVal();
SDOperand CP = DAG.getTargetConstantPool(C, MVT::i32,
cast<ConstantPoolSDNode>(Op)->getAlignment());
SDOperand Hi = DAG.getNode(SPISD::Hi, MVT::i32, CP);
SDOperand Lo = DAG.getNode(SPISD::Lo, MVT::i32, CP);
return DAG.getNode(ISD::ADD, MVT::i32, Lo, Hi);
}
case ISD::FP_TO_SINT:
// Convert the fp value to integer in an FP register.
assert(Op.getValueType() == MVT::i32);
Op = DAG.getNode(SPISD::FTOI, MVT::f32, Op.getOperand(0));
return DAG.getNode(ISD::BIT_CONVERT, MVT::i32, Op);
case ISD::SINT_TO_FP: {
assert(Op.getOperand(0).getValueType() == MVT::i32);
SDOperand Tmp = DAG.getNode(ISD::BIT_CONVERT, MVT::f32, Op.getOperand(0));
// Convert the int value to FP in an FP register.
return DAG.getNode(SPISD::ITOF, Op.getValueType(), Tmp);
}
case ISD::BR_CC: {
SDOperand Chain = Op.getOperand(0);
ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(1))->get();
SDOperand LHS = Op.getOperand(2);
SDOperand RHS = Op.getOperand(3);
SDOperand Dest = Op.getOperand(4);
unsigned Opc, SPCC = ~0U;
// If this is a br_cc of a "setcc", and if the setcc got lowered into
// an CMP[IF]CC/SELECT_[IF]CC pair, find the original compared values.
LookThroughSetCC(LHS, RHS, CC, SPCC);
// Get the condition flag.
SDOperand CompareFlag;
if (LHS.getValueType() == MVT::i32) {
std::vector<MVT::ValueType> VTs;
VTs.push_back(MVT::i32);
VTs.push_back(MVT::Flag);
SDOperand Ops[2] = { LHS, RHS };
CompareFlag = DAG.getNode(SPISD::CMPICC, VTs, Ops, 2).getValue(1);
if (SPCC == ~0U) SPCC = IntCondCCodeToICC(CC);
Opc = SPISD::BRICC;
} else {
CompareFlag = DAG.getNode(SPISD::CMPFCC, MVT::Flag, LHS, RHS);
if (SPCC == ~0U) SPCC = FPCondCCodeToFCC(CC);
Opc = SPISD::BRFCC;
}
return DAG.getNode(Opc, MVT::Other, Chain, Dest,
DAG.getConstant(SPCC, MVT::i32), CompareFlag);
}
case ISD::SELECT_CC: {
SDOperand LHS = Op.getOperand(0);
SDOperand RHS = Op.getOperand(1);
ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(4))->get();
SDOperand TrueVal = Op.getOperand(2);
SDOperand FalseVal = Op.getOperand(3);
unsigned Opc, SPCC = ~0U;
// If this is a select_cc of a "setcc", and if the setcc got lowered into
// an CMP[IF]CC/SELECT_[IF]CC pair, find the original compared values.
LookThroughSetCC(LHS, RHS, CC, SPCC);
SDOperand CompareFlag;
if (LHS.getValueType() == MVT::i32) {
std::vector<MVT::ValueType> VTs;
VTs.push_back(LHS.getValueType()); // subcc returns a value
VTs.push_back(MVT::Flag);
SDOperand Ops[2] = { LHS, RHS };
CompareFlag = DAG.getNode(SPISD::CMPICC, VTs, Ops, 2).getValue(1);
Opc = SPISD::SELECT_ICC;
if (SPCC == ~0U) SPCC = IntCondCCodeToICC(CC);
} else {
CompareFlag = DAG.getNode(SPISD::CMPFCC, MVT::Flag, LHS, RHS);
Opc = SPISD::SELECT_FCC;
if (SPCC == ~0U) SPCC = FPCondCCodeToFCC(CC);
}
return DAG.getNode(Opc, TrueVal.getValueType(), TrueVal, FalseVal,
DAG.getConstant(SPCC, MVT::i32), CompareFlag);
}
case ISD::VASTART: {
// vastart just stores the address of the VarArgsFrameIndex slot into the
// memory location argument.
SDOperand Offset = DAG.getNode(ISD::ADD, MVT::i32,
DAG.getRegister(SP::I6, MVT::i32),
DAG.getConstant(VarArgsFrameOffset, MVT::i32));
SrcValueSDNode *SV = cast<SrcValueSDNode>(Op.getOperand(2));
return DAG.getStore(Op.getOperand(0), Offset,
Op.getOperand(1), SV->getValue(), SV->getOffset());
}
case ISD::VAARG: {
SDNode *Node = Op.Val;
MVT::ValueType VT = Node->getValueType(0);
SDOperand InChain = Node->getOperand(0);
SDOperand VAListPtr = Node->getOperand(1);
SrcValueSDNode *SV = cast<SrcValueSDNode>(Node->getOperand(2));
SDOperand VAList = DAG.getLoad(getPointerTy(), InChain, VAListPtr,
SV->getValue(), SV->getOffset());
// Increment the pointer, VAList, to the next vaarg
SDOperand NextPtr = DAG.getNode(ISD::ADD, getPointerTy(), VAList,
DAG.getConstant(MVT::getSizeInBits(VT)/8,
getPointerTy()));
// Store the incremented VAList to the legalized pointer
InChain = DAG.getStore(VAList.getValue(1), NextPtr,
VAListPtr, SV->getValue(), SV->getOffset());
// Load the actual argument out of the pointer VAList, unless this is an
// f64 load.
if (VT != MVT::f64) {
return DAG.getLoad(VT, InChain, VAList, NULL, 0);
} else {
// Otherwise, load it as i64, then do a bitconvert.
SDOperand V = DAG.getLoad(MVT::i64, InChain, VAList, NULL, 0);
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::f64);
Tys.push_back(MVT::Other);
// Bit-Convert the value to f64.
SDOperand Ops[2] = { DAG.getNode(ISD::BIT_CONVERT, MVT::f64, V),
V.getValue(1) };
return DAG.getNode(ISD::MERGE_VALUES, Tys, Ops, 2);
}
}
case ISD::DYNAMIC_STACKALLOC: {
SDOperand Chain = Op.getOperand(0); // Legalize the chain.
SDOperand Size = Op.getOperand(1); // Legalize the size.
unsigned SPReg = SP::O6;
SDOperand SP = DAG.getCopyFromReg(Chain, SPReg, MVT::i32);
SDOperand NewSP = DAG.getNode(ISD::SUB, MVT::i32, SP, Size); // Value
Chain = DAG.getCopyToReg(SP.getValue(1), SPReg, NewSP); // Output chain
// The resultant pointer is actually 16 words from the bottom of the stack,
// to provide a register spill area.
SDOperand NewVal = DAG.getNode(ISD::ADD, MVT::i32, NewSP,
DAG.getConstant(96, MVT::i32));
std::vector<MVT::ValueType> Tys;
Tys.push_back(MVT::i32);
Tys.push_back(MVT::Other);
SDOperand Ops[2] = { NewVal, Chain };
return DAG.getNode(ISD::MERGE_VALUES, Tys, Ops, 2);
}
case ISD::RET: {
SDOperand Copy;
switch(Op.getNumOperands()) {
default:
assert(0 && "Do not know how to return this many arguments!");
abort();
case 1:
return SDOperand(); // ret void is legal
case 3: {
unsigned ArgReg;
switch(Op.getOperand(1).getValueType()) {
default: assert(0 && "Unknown type to return!");
case MVT::i32: ArgReg = SP::I0; break;
case MVT::f32: ArgReg = SP::F0; break;
case MVT::f64: ArgReg = SP::D0; break;
}
Copy = DAG.getCopyToReg(Op.getOperand(0), ArgReg, Op.getOperand(1),
SDOperand());
break;
}
case 5:
Copy = DAG.getCopyToReg(Op.getOperand(0), SP::I0, Op.getOperand(3),
SDOperand());
Copy = DAG.getCopyToReg(Copy, SP::I1, Op.getOperand(1), Copy.getValue(1));
break;
}
return DAG.getNode(SPISD::RET_FLAG, MVT::Other, Copy, Copy.getValue(1));
}
}
}
MachineBasicBlock *
SparcTargetLowering::InsertAtEndOfBasicBlock(MachineInstr *MI,
MachineBasicBlock *BB) {
unsigned BROpcode;
unsigned CC;
// Figure out the conditional branch opcode to use for this select_cc.
switch (MI->getOpcode()) {
default: assert(0 && "Unknown SELECT_CC!");
case SP::SELECT_CC_Int_ICC:
case SP::SELECT_CC_FP_ICC:
case SP::SELECT_CC_DFP_ICC:
BROpcode = SP::BCOND;
break;
case SP::SELECT_CC_Int_FCC:
case SP::SELECT_CC_FP_FCC:
case SP::SELECT_CC_DFP_FCC:
BROpcode = SP::FBCOND;
break;
}
CC = (SPCC::CondCodes)MI->getOperand(3).getImmedValue();
// To "insert" a SELECT_CC instruction, we actually have to insert the diamond
// control-flow pattern. The incoming instruction knows the destination vreg
// to set, the condition code register to branch on, the true/false values to
// select between, and a branch opcode to use.
const BasicBlock *LLVM_BB = BB->getBasicBlock();
ilist<MachineBasicBlock>::iterator It = BB;
++It;
// thisMBB:
// ...
// TrueVal = ...
// [f]bCC copy1MBB
// fallthrough --> copy0MBB
MachineBasicBlock *thisMBB = BB;
MachineBasicBlock *copy0MBB = new MachineBasicBlock(LLVM_BB);
MachineBasicBlock *sinkMBB = new MachineBasicBlock(LLVM_BB);
BuildMI(BB, BROpcode, 2).addMBB(sinkMBB).addImm(CC);
MachineFunction *F = BB->getParent();
F->getBasicBlockList().insert(It, copy0MBB);
F->getBasicBlockList().insert(It, sinkMBB);
// Update machine-CFG edges by first adding all successors of the current
// block to the new block which will contain the Phi node for the select.
for(MachineBasicBlock::succ_iterator i = BB->succ_begin(),
e = BB->succ_end(); i != e; ++i)
sinkMBB->addSuccessor(*i);
// Next, remove all successors of the current block, and add the true
// and fallthrough blocks as its successors.
while(!BB->succ_empty())
BB->removeSuccessor(BB->succ_begin());
BB->addSuccessor(copy0MBB);
BB->addSuccessor(sinkMBB);
// copy0MBB:
// %FalseValue = ...
// # fallthrough to sinkMBB
BB = copy0MBB;
// Update machine-CFG edges
BB->addSuccessor(sinkMBB);
// sinkMBB:
// %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
// ...
BB = sinkMBB;
BuildMI(BB, SP::PHI, 4, MI->getOperand(0).getReg())
.addReg(MI->getOperand(2).getReg()).addMBB(copy0MBB)
.addReg(MI->getOperand(1).getReg()).addMBB(thisMBB);
delete MI; // The pseudo instruction is gone now.
return BB;
}
//===----------------------------------------------------------------------===//
// Instruction Selector Implementation
//===----------------------------------------------------------------------===//
//===--------------------------------------------------------------------===//
/// SparcDAGToDAGISel - SPARC specific code to select SPARC machine
/// instructions for SelectionDAG operations.
///
namespace {
class SparcDAGToDAGISel : public SelectionDAGISel {
SparcTargetLowering Lowering;
/// Subtarget - Keep a pointer to the Sparc Subtarget around so that we can
/// make the right decision when generating code for different targets.
const SparcSubtarget &Subtarget;
public:
SparcDAGToDAGISel(TargetMachine &TM)
: SelectionDAGISel(Lowering), Lowering(TM),
Subtarget(TM.getSubtarget<SparcSubtarget>()) {
}
SDNode *Select(SDOperand Op);
// Complex Pattern Selectors.
bool SelectADDRrr(SDOperand N, SDOperand &R1, SDOperand &R2);
bool SelectADDRri(SDOperand N, SDOperand &Base, SDOperand &Offset);
/// InstructionSelectBasicBlock - This callback is invoked by
/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
virtual void InstructionSelectBasicBlock(SelectionDAG &DAG);
virtual const char *getPassName() const {
return "SPARC DAG->DAG Pattern Instruction Selection";
}
// Include the pieces autogenerated from the target description.
#include "SparcGenDAGISel.inc"
};
} // end anonymous namespace
/// InstructionSelectBasicBlock - This callback is invoked by
/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
void SparcDAGToDAGISel::InstructionSelectBasicBlock(SelectionDAG &DAG) {
DEBUG(BB->dump());
// Select target instructions for the DAG.
DAG.setRoot(SelectRoot(DAG.getRoot()));
DAG.RemoveDeadNodes();
// Emit machine code to BB.
ScheduleAndEmitDAG(DAG);
}
bool SparcDAGToDAGISel::SelectADDRri(SDOperand Addr, SDOperand &Base,
SDOperand &Offset) {
if (FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>(Addr)) {
Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), MVT::i32);
Offset = CurDAG->getTargetConstant(0, MVT::i32);
return true;
}
if (Addr.getOpcode() == ISD::TargetExternalSymbol ||
Addr.getOpcode() == ISD::TargetGlobalAddress)
return false; // direct calls.
if (Addr.getOpcode() == ISD::ADD) {
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1))) {
if (Predicate_simm13(CN)) {
if (FrameIndexSDNode *FIN =
dyn_cast<FrameIndexSDNode>(Addr.getOperand(0))) {
// Constant offset from frame ref.
Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), MVT::i32);
} else {
Base = Addr.getOperand(0);
}
Offset = CurDAG->getTargetConstant(CN->getValue(), MVT::i32);
return true;
}
}
if (Addr.getOperand(0).getOpcode() == SPISD::Lo) {
Base = Addr.getOperand(1);
Offset = Addr.getOperand(0).getOperand(0);
return true;
}
if (Addr.getOperand(1).getOpcode() == SPISD::Lo) {
Base = Addr.getOperand(0);
Offset = Addr.getOperand(1).getOperand(0);
return true;
}
}
Base = Addr;
Offset = CurDAG->getTargetConstant(0, MVT::i32);
return true;
}
bool SparcDAGToDAGISel::SelectADDRrr(SDOperand Addr, SDOperand &R1,
SDOperand &R2) {
if (Addr.getOpcode() == ISD::FrameIndex) return false;
if (Addr.getOpcode() == ISD::TargetExternalSymbol ||
Addr.getOpcode() == ISD::TargetGlobalAddress)
return false; // direct calls.
if (Addr.getOpcode() == ISD::ADD) {
if (isa<ConstantSDNode>(Addr.getOperand(1)) &&
Predicate_simm13(Addr.getOperand(1).Val))
return false; // Let the reg+imm pattern catch this!
if (Addr.getOperand(0).getOpcode() == SPISD::Lo ||
Addr.getOperand(1).getOpcode() == SPISD::Lo)
return false; // Let the reg+imm pattern catch this!
R1 = Addr.getOperand(0);
R2 = Addr.getOperand(1);
return true;
}
R1 = Addr;
R2 = CurDAG->getRegister(SP::G0, MVT::i32);
return true;
}
SDNode *SparcDAGToDAGISel::Select(SDOperand Op) {
SDNode *N = Op.Val;
if (N->getOpcode() >= ISD::BUILTIN_OP_END &&
N->getOpcode() < SPISD::FIRST_NUMBER)
return NULL; // Already selected.
switch (N->getOpcode()) {
default: break;
case ISD::SDIV:
case ISD::UDIV: {
// FIXME: should use a custom expander to expose the SRA to the dag.
SDOperand DivLHS = N->getOperand(0);
SDOperand DivRHS = N->getOperand(1);
AddToISelQueue(DivLHS);
AddToISelQueue(DivRHS);
// Set the Y register to the high-part.
SDOperand TopPart;
if (N->getOpcode() == ISD::SDIV) {
TopPart = SDOperand(CurDAG->getTargetNode(SP::SRAri, MVT::i32, DivLHS,
CurDAG->getTargetConstant(31, MVT::i32)), 0);
} else {
TopPart = CurDAG->getRegister(SP::G0, MVT::i32);
}
TopPart = SDOperand(CurDAG->getTargetNode(SP::WRYrr, MVT::Flag, TopPart,
CurDAG->getRegister(SP::G0, MVT::i32)), 0);
// FIXME: Handle div by immediate.
unsigned Opcode = N->getOpcode() == ISD::SDIV ? SP::SDIVrr : SP::UDIVrr;
return CurDAG->SelectNodeTo(N, Opcode, MVT::i32, DivLHS, DivRHS,
TopPart);
}
case ISD::MULHU:
case ISD::MULHS: {
// FIXME: Handle mul by immediate.
SDOperand MulLHS = N->getOperand(0);
SDOperand MulRHS = N->getOperand(1);
AddToISelQueue(MulLHS);
AddToISelQueue(MulRHS);
unsigned Opcode = N->getOpcode() == ISD::MULHU ? SP::UMULrr : SP::SMULrr;
SDNode *Mul = CurDAG->getTargetNode(Opcode, MVT::i32, MVT::Flag,
MulLHS, MulRHS);
// The high part is in the Y register.
return CurDAG->SelectNodeTo(N, SP::RDY, MVT::i32, SDOperand(Mul, 1));
return NULL;
}
}
return SelectCode(Op);
}
/// createSparcISelDag - This pass converts a legalized DAG into a
/// SPARC-specific DAG, ready for instruction scheduling.
///
FunctionPass *llvm::createSparcISelDag(TargetMachine &TM) {
return new SparcDAGToDAGISel(TM);
}