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llvm-project/llvm/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodesEmit.cpp

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//===---- ScheduleDAGEmit.cpp - Emit routines for the ScheduleDAG class ---===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This implements the Emit routines for the ScheduleDAG class, which creates
// MachineInstrs according to the computed schedule.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "pre-RA-sched"
#include "ScheduleDAGSDNodes.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
using namespace llvm;
/// getInstrOperandRegClass - Return register class of the operand of an
/// instruction of the specified TargetInstrDesc.
static const TargetRegisterClass*
getInstrOperandRegClass(const TargetRegisterInfo *TRI,
const TargetInstrDesc &II, unsigned Op) {
if (Op >= II.getNumOperands()) {
assert(II.isVariadic() && "Invalid operand # of instruction");
return NULL;
}
if (II.OpInfo[Op].isLookupPtrRegClass())
return TRI->getPointerRegClass();
return TRI->getRegClass(II.OpInfo[Op].RegClass);
}
/// EmitCopyFromReg - Generate machine code for an CopyFromReg node or an
/// implicit physical register output.
void ScheduleDAGSDNodes::EmitCopyFromReg(SDNode *Node, unsigned ResNo,
bool IsClone, bool IsCloned,
unsigned SrcReg,
DenseMap<SDValue, unsigned> &VRBaseMap) {
unsigned VRBase = 0;
if (TargetRegisterInfo::isVirtualRegister(SrcReg)) {
// Just use the input register directly!
SDValue Op(Node, ResNo);
if (IsClone)
VRBaseMap.erase(Op);
bool isNew = VRBaseMap.insert(std::make_pair(Op, SrcReg)).second;
isNew = isNew; // Silence compiler warning.
assert(isNew && "Node emitted out of order - early");
return;
}
// If the node is only used by a CopyToReg and the dest reg is a vreg, use
// the CopyToReg'd destination register instead of creating a new vreg.
bool MatchReg = true;
const TargetRegisterClass *UseRC = NULL;
if (!IsClone && !IsCloned)
for (SDNode::use_iterator UI = Node->use_begin(), E = Node->use_end();
UI != E; ++UI) {
SDNode *User = *UI;
bool Match = true;
if (User->getOpcode() == ISD::CopyToReg &&
User->getOperand(2).getNode() == Node &&
User->getOperand(2).getResNo() == ResNo) {
unsigned DestReg = cast<RegisterSDNode>(User->getOperand(1))->getReg();
if (TargetRegisterInfo::isVirtualRegister(DestReg)) {
VRBase = DestReg;
Match = false;
} else if (DestReg != SrcReg)
Match = false;
} else {
for (unsigned i = 0, e = User->getNumOperands(); i != e; ++i) {
SDValue Op = User->getOperand(i);
if (Op.getNode() != Node || Op.getResNo() != ResNo)
continue;
MVT VT = Node->getValueType(Op.getResNo());
if (VT == MVT::Other || VT == MVT::Flag)
continue;
Match = false;
if (User->isMachineOpcode()) {
const TargetInstrDesc &II = TII->get(User->getMachineOpcode());
const TargetRegisterClass *RC =
getInstrOperandRegClass(TRI, II, i+II.getNumDefs());
if (!UseRC)
UseRC = RC;
else if (RC) {
if (UseRC->hasSuperClass(RC))
UseRC = RC;
else
assert((UseRC == RC || RC->hasSuperClass(UseRC)) &&
"Multiple uses expecting different register classes!");
}
}
}
}
MatchReg &= Match;
if (VRBase)
break;
}
MVT VT = Node->getValueType(ResNo);
const TargetRegisterClass *SrcRC = 0, *DstRC = 0;
SrcRC = TRI->getPhysicalRegisterRegClass(SrcReg, VT);
// Figure out the register class to create for the destreg.
if (VRBase) {
DstRC = MRI.getRegClass(VRBase);
} else if (UseRC) {
assert(UseRC->hasType(VT) && "Incompatible phys register def and uses!");
DstRC = UseRC;
} else {
DstRC = TLI->getRegClassFor(VT);
}
// If all uses are reading from the src physical register and copying the
// register is either impossible or very expensive, then don't create a copy.
if (MatchReg && SrcRC->getCopyCost() < 0) {
VRBase = SrcReg;
} else {
// Create the reg, emit the copy.
VRBase = MRI.createVirtualRegister(DstRC);
bool Emitted = TII->copyRegToReg(*BB, InsertPos, VRBase, SrcReg,
DstRC, SrcRC);
// If the target didn't handle the copy with different register
// classes and the destination is a subset of the source,
// try a normal same-RC copy.
if (!Emitted && DstRC->hasSuperClass(SrcRC))
Emitted = TII->copyRegToReg(*BB, InsertPos, VRBase, SrcReg,
SrcRC, SrcRC);
assert(Emitted && "Unable to issue a copy instruction!\n");
}
SDValue Op(Node, ResNo);
if (IsClone)
VRBaseMap.erase(Op);
bool isNew = VRBaseMap.insert(std::make_pair(Op, VRBase)).second;
isNew = isNew; // Silence compiler warning.
assert(isNew && "Node emitted out of order - early");
}
/// getDstOfCopyToRegUse - If the only use of the specified result number of
/// node is a CopyToReg, return its destination register. Return 0 otherwise.
unsigned ScheduleDAGSDNodes::getDstOfOnlyCopyToRegUse(SDNode *Node,
unsigned ResNo) const {
if (!Node->hasOneUse())
return 0;
SDNode *User = *Node->use_begin();
if (User->getOpcode() == ISD::CopyToReg &&
User->getOperand(2).getNode() == Node &&
User->getOperand(2).getResNo() == ResNo) {
unsigned Reg = cast<RegisterSDNode>(User->getOperand(1))->getReg();
if (TargetRegisterInfo::isVirtualRegister(Reg))
return Reg;
}
return 0;
}
void ScheduleDAGSDNodes::CreateVirtualRegisters(SDNode *Node, MachineInstr *MI,
const TargetInstrDesc &II,
bool IsClone, bool IsCloned,
DenseMap<SDValue, unsigned> &VRBaseMap) {
assert(Node->getMachineOpcode() != TargetInstrInfo::IMPLICIT_DEF &&
"IMPLICIT_DEF should have been handled as a special case elsewhere!");
for (unsigned i = 0; i < II.getNumDefs(); ++i) {
// If the specific node value is only used by a CopyToReg and the dest reg
// is a vreg in the same register class, use the CopyToReg'd destination
// register instead of creating a new vreg.
unsigned VRBase = 0;
const TargetRegisterClass *RC = getInstrOperandRegClass(TRI, II, i);
if (!IsClone && !IsCloned)
for (SDNode::use_iterator UI = Node->use_begin(), E = Node->use_end();
UI != E; ++UI) {
SDNode *User = *UI;
if (User->getOpcode() == ISD::CopyToReg &&
User->getOperand(2).getNode() == Node &&
User->getOperand(2).getResNo() == i) {
unsigned Reg = cast<RegisterSDNode>(User->getOperand(1))->getReg();
if (TargetRegisterInfo::isVirtualRegister(Reg)) {
const TargetRegisterClass *RegRC = MRI.getRegClass(Reg);
if (RegRC == RC) {
VRBase = Reg;
MI->addOperand(MachineOperand::CreateReg(Reg, true));
break;
}
}
}
}
// Create the result registers for this node and add the result regs to
// the machine instruction.
if (VRBase == 0) {
assert(RC && "Isn't a register operand!");
VRBase = MRI.createVirtualRegister(RC);
MI->addOperand(MachineOperand::CreateReg(VRBase, true));
}
SDValue Op(Node, i);
if (IsClone)
VRBaseMap.erase(Op);
bool isNew = VRBaseMap.insert(std::make_pair(Op, VRBase)).second;
isNew = isNew; // Silence compiler warning.
assert(isNew && "Node emitted out of order - early");
}
}
/// getVR - Return the virtual register corresponding to the specified result
/// of the specified node.
unsigned ScheduleDAGSDNodes::getVR(SDValue Op,
DenseMap<SDValue, unsigned> &VRBaseMap) {
if (Op.isMachineOpcode() &&
Op.getMachineOpcode() == TargetInstrInfo::IMPLICIT_DEF) {
// Add an IMPLICIT_DEF instruction before every use.
unsigned VReg = getDstOfOnlyCopyToRegUse(Op.getNode(), Op.getResNo());
// IMPLICIT_DEF can produce any type of result so its TargetInstrDesc
// does not include operand register class info.
if (!VReg) {
const TargetRegisterClass *RC = TLI->getRegClassFor(Op.getValueType());
VReg = MRI.createVirtualRegister(RC);
}
BuildMI(BB, Op.getDebugLoc(), TII->get(TargetInstrInfo::IMPLICIT_DEF),VReg);
return VReg;
}
DenseMap<SDValue, unsigned>::iterator I = VRBaseMap.find(Op);
assert(I != VRBaseMap.end() && "Node emitted out of order - late");
return I->second;
}
/// AddRegisterOperand - Add the specified register as an operand to the
/// specified machine instr. Insert register copies if the register is
/// not in the required register class.
void
ScheduleDAGSDNodes::AddRegisterOperand(MachineInstr *MI, SDValue Op,
unsigned IIOpNum,
const TargetInstrDesc *II,
DenseMap<SDValue, unsigned> &VRBaseMap) {
assert(Op.getValueType() != MVT::Other &&
Op.getValueType() != MVT::Flag &&
"Chain and flag operands should occur at end of operand list!");
// Get/emit the operand.
unsigned VReg = getVR(Op, VRBaseMap);
assert(TargetRegisterInfo::isVirtualRegister(VReg) && "Not a vreg?");
const TargetInstrDesc &TID = MI->getDesc();
bool isOptDef = IIOpNum < TID.getNumOperands() &&
TID.OpInfo[IIOpNum].isOptionalDef();
// If the instruction requires a register in a different class, create
// a new virtual register and copy the value into it.
if (II) {
const TargetRegisterClass *SrcRC =
MRI.getRegClass(VReg);
const TargetRegisterClass *DstRC =
getInstrOperandRegClass(TRI, *II, IIOpNum);
assert((DstRC || (TID.isVariadic() && IIOpNum >= TID.getNumOperands())) &&
"Don't have operand info for this instruction!");
if (DstRC && SrcRC != DstRC && !SrcRC->hasSuperClass(DstRC)) {
unsigned NewVReg = MRI.createVirtualRegister(DstRC);
bool Emitted = TII->copyRegToReg(*BB, InsertPos, NewVReg, VReg,
DstRC, SrcRC);
// If the target didn't handle the copy with different register
// classes and the destination is a subset of the source,
// try a normal same-RC copy.
if (!Emitted && DstRC->hasSuperClass(SrcRC))
Emitted = TII->copyRegToReg(*BB, InsertPos, NewVReg, VReg,
SrcRC, SrcRC);
assert(Emitted && "Unable to issue a copy instruction!\n");
VReg = NewVReg;
}
}
MI->addOperand(MachineOperand::CreateReg(VReg, isOptDef));
}
/// AddOperand - Add the specified operand to the specified machine instr. II
/// specifies the instruction information for the node, and IIOpNum is the
/// operand number (in the II) that we are adding. IIOpNum and II are used for
/// assertions only.
void ScheduleDAGSDNodes::AddOperand(MachineInstr *MI, SDValue Op,
unsigned IIOpNum,
const TargetInstrDesc *II,
DenseMap<SDValue, unsigned> &VRBaseMap) {
if (Op.isMachineOpcode()) {
AddRegisterOperand(MI, Op, IIOpNum, II, VRBaseMap);
} else if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
MI->addOperand(MachineOperand::CreateImm(C->getZExtValue()));
} else if (ConstantFPSDNode *F = dyn_cast<ConstantFPSDNode>(Op)) {
const ConstantFP *CFP = F->getConstantFPValue();
MI->addOperand(MachineOperand::CreateFPImm(CFP));
} else if (RegisterSDNode *R = dyn_cast<RegisterSDNode>(Op)) {
MI->addOperand(MachineOperand::CreateReg(R->getReg(), false));
} else if (GlobalAddressSDNode *TGA = dyn_cast<GlobalAddressSDNode>(Op)) {
MI->addOperand(MachineOperand::CreateGA(TGA->getGlobal(),TGA->getOffset()));
} else if (BasicBlockSDNode *BBNode = dyn_cast<BasicBlockSDNode>(Op)) {
MI->addOperand(MachineOperand::CreateMBB(BBNode->getBasicBlock()));
} else if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(Op)) {
MI->addOperand(MachineOperand::CreateFI(FI->getIndex()));
} else if (JumpTableSDNode *JT = dyn_cast<JumpTableSDNode>(Op)) {
MI->addOperand(MachineOperand::CreateJTI(JT->getIndex()));
} else if (ConstantPoolSDNode *CP = dyn_cast<ConstantPoolSDNode>(Op)) {
int Offset = CP->getOffset();
unsigned Align = CP->getAlignment();
const Type *Type = CP->getType();
// MachineConstantPool wants an explicit alignment.
if (Align == 0) {
Align = TM.getTargetData()->getPrefTypeAlignment(Type);
if (Align == 0) {
// Alignment of vector types. FIXME!
Align = TM.getTargetData()->getTypePaddedSize(Type);
}
}
unsigned Idx;
if (CP->isMachineConstantPoolEntry())
Idx = ConstPool->getConstantPoolIndex(CP->getMachineCPVal(), Align);
else
Idx = ConstPool->getConstantPoolIndex(CP->getConstVal(), Align);
MI->addOperand(MachineOperand::CreateCPI(Idx, Offset));
} else if (ExternalSymbolSDNode *ES = dyn_cast<ExternalSymbolSDNode>(Op)) {
MI->addOperand(MachineOperand::CreateES(ES->getSymbol()));
} else {
assert(Op.getValueType() != MVT::Other &&
Op.getValueType() != MVT::Flag &&
"Chain and flag operands should occur at end of operand list!");
AddRegisterOperand(MI, Op, IIOpNum, II, VRBaseMap);
}
}
/// getSubRegisterRegClass - Returns the register class of specified register
/// class' "SubIdx"'th sub-register class.
static const TargetRegisterClass*
getSubRegisterRegClass(const TargetRegisterClass *TRC, unsigned SubIdx) {
// Pick the register class of the subregister
TargetRegisterInfo::regclass_iterator I =
TRC->subregclasses_begin() + SubIdx-1;
assert(I < TRC->subregclasses_end() &&
"Invalid subregister index for register class");
return *I;
}
/// getSuperRegisterRegClass - Returns the register class of a superreg A whose
/// "SubIdx"'th sub-register class is the specified register class and whose
/// type matches the specified type.
static const TargetRegisterClass*
getSuperRegisterRegClass(const TargetRegisterClass *TRC,
unsigned SubIdx, MVT VT) {
// Pick the register class of the superegister for this type
for (TargetRegisterInfo::regclass_iterator I = TRC->superregclasses_begin(),
E = TRC->superregclasses_end(); I != E; ++I)
if ((*I)->hasType(VT) && getSubRegisterRegClass(*I, SubIdx) == TRC)
return *I;
assert(false && "Couldn't find the register class");
return 0;
}
/// EmitSubregNode - Generate machine code for subreg nodes.
///
void ScheduleDAGSDNodes::EmitSubregNode(SDNode *Node,
DenseMap<SDValue, unsigned> &VRBaseMap) {
unsigned VRBase = 0;
unsigned Opc = Node->getMachineOpcode();
// If the node is only used by a CopyToReg and the dest reg is a vreg, use
// the CopyToReg'd destination register instead of creating a new vreg.
for (SDNode::use_iterator UI = Node->use_begin(), E = Node->use_end();
UI != E; ++UI) {
SDNode *User = *UI;
if (User->getOpcode() == ISD::CopyToReg &&
User->getOperand(2).getNode() == Node) {
unsigned DestReg = cast<RegisterSDNode>(User->getOperand(1))->getReg();
if (TargetRegisterInfo::isVirtualRegister(DestReg)) {
VRBase = DestReg;
break;
}
}
}
if (Opc == TargetInstrInfo::EXTRACT_SUBREG) {
unsigned SubIdx = cast<ConstantSDNode>(Node->getOperand(1))->getZExtValue();
// Create the extract_subreg machine instruction.
MachineInstr *MI = BuildMI(MF, Node->getDebugLoc(),
TII->get(TargetInstrInfo::EXTRACT_SUBREG));
// Figure out the register class to create for the destreg.
unsigned VReg = getVR(Node->getOperand(0), VRBaseMap);
const TargetRegisterClass *TRC = MRI.getRegClass(VReg);
const TargetRegisterClass *SRC = getSubRegisterRegClass(TRC, SubIdx);
// Figure out the register class to create for the destreg.
// Note that if we're going to directly use an existing register,
// it must be precisely the required class, and not a subclass
// thereof.
if (VRBase == 0 || SRC != MRI.getRegClass(VRBase)) {
// Create the reg
assert(SRC && "Couldn't find source register class");
VRBase = MRI.createVirtualRegister(SRC);
}
// Add def, source, and subreg index
MI->addOperand(MachineOperand::CreateReg(VRBase, true));
AddOperand(MI, Node->getOperand(0), 0, 0, VRBaseMap);
MI->addOperand(MachineOperand::CreateImm(SubIdx));
BB->insert(InsertPos, MI);
} else if (Opc == TargetInstrInfo::INSERT_SUBREG ||
Opc == TargetInstrInfo::SUBREG_TO_REG) {
SDValue N0 = Node->getOperand(0);
SDValue N1 = Node->getOperand(1);
SDValue N2 = Node->getOperand(2);
unsigned SubReg = getVR(N1, VRBaseMap);
unsigned SubIdx = cast<ConstantSDNode>(N2)->getZExtValue();
const TargetRegisterClass *TRC = MRI.getRegClass(SubReg);
const TargetRegisterClass *SRC =
getSuperRegisterRegClass(TRC, SubIdx,
Node->getValueType(0));
// Figure out the register class to create for the destreg.
// Note that if we're going to directly use an existing register,
// it must be precisely the required class, and not a subclass
// thereof.
if (VRBase == 0 || SRC != MRI.getRegClass(VRBase)) {
// Create the reg
assert(SRC && "Couldn't find source register class");
VRBase = MRI.createVirtualRegister(SRC);
}
// Create the insert_subreg or subreg_to_reg machine instruction.
MachineInstr *MI = BuildMI(MF, Node->getDebugLoc(), TII->get(Opc));
MI->addOperand(MachineOperand::CreateReg(VRBase, true));
// If creating a subreg_to_reg, then the first input operand
// is an implicit value immediate, otherwise it's a register
if (Opc == TargetInstrInfo::SUBREG_TO_REG) {
const ConstantSDNode *SD = cast<ConstantSDNode>(N0);
MI->addOperand(MachineOperand::CreateImm(SD->getZExtValue()));
} else
AddOperand(MI, N0, 0, 0, VRBaseMap);
// Add the subregster being inserted
AddOperand(MI, N1, 0, 0, VRBaseMap);
MI->addOperand(MachineOperand::CreateImm(SubIdx));
BB->insert(InsertPos, MI);
} else
assert(0 && "Node is not insert_subreg, extract_subreg, or subreg_to_reg");
SDValue Op(Node, 0);
bool isNew = VRBaseMap.insert(std::make_pair(Op, VRBase)).second;
isNew = isNew; // Silence compiler warning.
assert(isNew && "Node emitted out of order - early");
}
/// EmitCopyToRegClassNode - Generate machine code for COPY_TO_REGCLASS nodes.
/// COPY_TO_REGCLASS is just a normal copy, except that the destination
/// register is constrained to be in a particular register class.
///
void
ScheduleDAGSDNodes::EmitCopyToRegClassNode(SDNode *Node,
DenseMap<SDValue, unsigned> &VRBaseMap) {
unsigned VReg = getVR(Node->getOperand(0), VRBaseMap);
const TargetRegisterClass *SrcRC = MRI.getRegClass(VReg);
unsigned DstRCIdx = cast<ConstantSDNode>(Node->getOperand(1))->getZExtValue();
const TargetRegisterClass *DstRC = TRI->getRegClass(DstRCIdx);
// Create the new VReg in the destination class and emit a copy.
unsigned NewVReg = MRI.createVirtualRegister(DstRC);
bool Emitted = TII->copyRegToReg(*BB, InsertPos, NewVReg, VReg,
DstRC, SrcRC);
// If the target didn't handle the copy with different register
// classes and the destination is a subset of the source,
// try a normal same-RC copy.
if (!Emitted && SrcRC->hasSubClass(DstRC))
Emitted = TII->copyRegToReg(*BB, InsertPos, NewVReg, VReg,
SrcRC, SrcRC);
assert(Emitted &&
"Unable to issue a copy instruction for a COPY_TO_REGCLASS node!\n");
SDValue Op(Node, 0);
bool isNew = VRBaseMap.insert(std::make_pair(Op, NewVReg)).second;
isNew = isNew; // Silence compiler warning.
assert(isNew && "Node emitted out of order - early");
}
/// EmitNode - Generate machine code for an node and needed dependencies.
///
void ScheduleDAGSDNodes::EmitNode(SDNode *Node, bool IsClone, bool IsCloned,
DenseMap<SDValue, unsigned> &VRBaseMap) {
// If machine instruction
if (Node->isMachineOpcode()) {
unsigned Opc = Node->getMachineOpcode();
// Handle subreg insert/extract specially
if (Opc == TargetInstrInfo::EXTRACT_SUBREG ||
Opc == TargetInstrInfo::INSERT_SUBREG ||
Opc == TargetInstrInfo::SUBREG_TO_REG) {
EmitSubregNode(Node, VRBaseMap);
return;
}
// Handle COPY_TO_REGCLASS specially.
if (Opc == TargetInstrInfo::COPY_TO_REGCLASS) {
EmitCopyToRegClassNode(Node, VRBaseMap);
return;
}
if (Opc == TargetInstrInfo::IMPLICIT_DEF)
// We want a unique VR for each IMPLICIT_DEF use.
return;
const TargetInstrDesc &II = TII->get(Opc);
unsigned NumResults = CountResults(Node);
unsigned NodeOperands = CountOperands(Node);
unsigned MemOperandsEnd = ComputeMemOperandsEnd(Node);
bool HasPhysRegOuts = (NumResults > II.getNumDefs()) &&
II.getImplicitDefs() != 0;
#ifndef NDEBUG
unsigned NumMIOperands = NodeOperands + NumResults;
assert((II.getNumOperands() == NumMIOperands ||
HasPhysRegOuts || II.isVariadic()) &&
"#operands for dag node doesn't match .td file!");
#endif
// Create the new machine instruction.
MachineInstr *MI = BuildMI(MF, Node->getDebugLoc(), II);
// Add result register values for things that are defined by this
// instruction.
if (NumResults)
CreateVirtualRegisters(Node, MI, II, IsClone, IsCloned, VRBaseMap);
// Emit all of the actual operands of this instruction, adding them to the
// instruction as appropriate.
for (unsigned i = 0; i != NodeOperands; ++i)
AddOperand(MI, Node->getOperand(i), i+II.getNumDefs(), &II, VRBaseMap);
// Emit all of the memory operands of this instruction
for (unsigned i = NodeOperands; i != MemOperandsEnd; ++i)
AddMemOperand(MI, cast<MemOperandSDNode>(Node->getOperand(i))->MO);
if (II.usesCustomDAGSchedInsertionHook()) {
// Insert this instruction into the basic block using a target
// specific inserter which may returns a new basic block.
BB = TLI->EmitInstrWithCustomInserter(MI, BB);
InsertPos = BB->end();
} else {
BB->insert(InsertPos, MI);
}
// Additional results must be an physical register def.
if (HasPhysRegOuts) {
for (unsigned i = II.getNumDefs(); i < NumResults; ++i) {
unsigned Reg = II.getImplicitDefs()[i - II.getNumDefs()];
if (Node->hasAnyUseOfValue(i))
EmitCopyFromReg(Node, i, IsClone, IsCloned, Reg, VRBaseMap);
}
}
return;
}
switch (Node->getOpcode()) {
default:
#ifndef NDEBUG
Node->dump(DAG);
#endif
assert(0 && "This target-independent node should have been selected!");
break;
case ISD::EntryToken:
assert(0 && "EntryToken should have been excluded from the schedule!");
break;
case ISD::TokenFactor: // fall thru
break;
case ISD::CopyToReg: {
unsigned SrcReg;
SDValue SrcVal = Node->getOperand(2);
if (RegisterSDNode *R = dyn_cast<RegisterSDNode>(SrcVal))
SrcReg = R->getReg();
else
SrcReg = getVR(SrcVal, VRBaseMap);
unsigned DestReg = cast<RegisterSDNode>(Node->getOperand(1))->getReg();
if (SrcReg == DestReg) // Coalesced away the copy? Ignore.
break;
const TargetRegisterClass *SrcTRC = 0, *DstTRC = 0;
// Get the register classes of the src/dst.
if (TargetRegisterInfo::isVirtualRegister(SrcReg))
SrcTRC = MRI.getRegClass(SrcReg);
else
SrcTRC = TRI->getPhysicalRegisterRegClass(SrcReg,SrcVal.getValueType());
if (TargetRegisterInfo::isVirtualRegister(DestReg))
DstTRC = MRI.getRegClass(DestReg);
else
DstTRC = TRI->getPhysicalRegisterRegClass(DestReg,
Node->getOperand(1).getValueType());
bool Emitted = TII->copyRegToReg(*BB, InsertPos, DestReg, SrcReg,
DstTRC, SrcTRC);
// If the target didn't handle the copy with different register
// classes and the destination is a subset of the source,
// try a normal same-RC copy.
if (!Emitted && DstTRC->hasSubClass(SrcTRC))
Emitted = TII->copyRegToReg(*BB, InsertPos, DestReg, SrcReg,
DstTRC, DstTRC);
assert(Emitted && "Unable to issue a copy instruction!\n");
break;
}
case ISD::CopyFromReg: {
unsigned SrcReg = cast<RegisterSDNode>(Node->getOperand(1))->getReg();
EmitCopyFromReg(Node, 0, IsClone, IsCloned, SrcReg, VRBaseMap);
break;
}
case ISD::INLINEASM: {
unsigned NumOps = Node->getNumOperands();
if (Node->getOperand(NumOps-1).getValueType() == MVT::Flag)
--NumOps; // Ignore the flag operand.
// Create the inline asm machine instruction.
MachineInstr *MI = BuildMI(MF, Node->getDebugLoc(),
TII->get(TargetInstrInfo::INLINEASM));
// Add the asm string as an external symbol operand.
const char *AsmStr =
cast<ExternalSymbolSDNode>(Node->getOperand(1))->getSymbol();
MI->addOperand(MachineOperand::CreateES(AsmStr));
// Add all of the operand registers to the instruction.
for (unsigned i = 2; i != NumOps;) {
unsigned Flags =
cast<ConstantSDNode>(Node->getOperand(i))->getZExtValue();
unsigned NumVals = InlineAsm::getNumOperandRegisters(Flags);
MI->addOperand(MachineOperand::CreateImm(Flags));
++i; // Skip the ID value.
switch (Flags & 7) {
default: assert(0 && "Bad flags!");
case 2: // Def of register.
for (; NumVals; --NumVals, ++i) {
unsigned Reg = cast<RegisterSDNode>(Node->getOperand(i))->getReg();
MI->addOperand(MachineOperand::CreateReg(Reg, true));
}
break;
case 6: // Def of earlyclobber register.
for (; NumVals; --NumVals, ++i) {
unsigned Reg = cast<RegisterSDNode>(Node->getOperand(i))->getReg();
MI->addOperand(MachineOperand::CreateReg(Reg, true, false, false,
false, 0, true));
}
break;
case 1: // Use of register.
case 3: // Immediate.
case 4: // Addressing mode.
// The addressing mode has been selected, just add all of the
// operands to the machine instruction.
for (; NumVals; --NumVals, ++i)
AddOperand(MI, Node->getOperand(i), 0, 0, VRBaseMap);
break;
}
}
BB->insert(InsertPos, MI);
break;
}
}
}
/// EmitSchedule - Emit the machine code in scheduled order.
MachineBasicBlock *ScheduleDAGSDNodes::EmitSchedule() {
DenseMap<SDValue, unsigned> VRBaseMap;
DenseMap<SUnit*, unsigned> CopyVRBaseMap;
for (unsigned i = 0, e = Sequence.size(); i != e; i++) {
SUnit *SU = Sequence[i];
if (!SU) {
// Null SUnit* is a noop.
EmitNoop();
continue;
}
// For pre-regalloc scheduling, create instructions corresponding to the
// SDNode and any flagged SDNodes and append them to the block.
if (!SU->getNode()) {
// Emit a copy.
EmitPhysRegCopy(SU, CopyVRBaseMap);
continue;
}
SmallVector<SDNode *, 4> FlaggedNodes;
for (SDNode *N = SU->getNode()->getFlaggedNode(); N;
N = N->getFlaggedNode())
FlaggedNodes.push_back(N);
while (!FlaggedNodes.empty()) {
EmitNode(FlaggedNodes.back(), SU->OrigNode != SU, SU->isCloned,VRBaseMap);
FlaggedNodes.pop_back();
}
EmitNode(SU->getNode(), SU->OrigNode != SU, SU->isCloned, VRBaseMap);
}
return BB;
}
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