Create a new InstrEmitter class for translating SelectionDAG nodes
into MachineInstrs. This is mostly just moving the code from
ScheduleDAGSDNodesEmit.cpp into a new class. This decouples MachineInstr
emitting from scheduling.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83699 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/InstrEmitter.cpp b/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
new file mode 100644
index 0000000..d3ffb2a
--- /dev/null
+++ b/lib/CodeGen/SelectionDAG/InstrEmitter.cpp
@@ -0,0 +1,693 @@
+//==--- InstrEmitter.cpp - Emit MachineInstrs for the SelectionDAG 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 SelectionDAG class, which creates
+// MachineInstrs based on the decisions of the SelectionDAG instruction
+// selection.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "instr-emitter"
+#include "InstrEmitter.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/ErrorHandling.h"
+#include "llvm/Support/MathExtras.h"
+using namespace llvm;
+
+/// CountResults - The results of target nodes have register or immediate
+/// operands first, then an optional chain, and optional flag operands (which do
+/// not go into the resulting MachineInstr).
+unsigned InstrEmitter::CountResults(SDNode *Node) {
+ unsigned N = Node->getNumValues();
+ while (N && Node->getValueType(N - 1) == MVT::Flag)
+ --N;
+ if (N && Node->getValueType(N - 1) == MVT::Other)
+ --N; // Skip over chain result.
+ return N;
+}
+
+/// CountOperands - The inputs to target nodes have any actual inputs first,
+/// followed by an optional chain operand, then an optional flag operand.
+/// Compute the number of actual operands that will go into the resulting
+/// MachineInstr.
+unsigned InstrEmitter::CountOperands(SDNode *Node) {
+ unsigned N = Node->getNumOperands();
+ while (N && Node->getOperand(N - 1).getValueType() == MVT::Flag)
+ --N;
+ if (N && Node->getOperand(N - 1).getValueType() == MVT::Other)
+ --N; // Ignore chain if it exists.
+ return N;
+}
+
+/// EmitCopyFromReg - Generate machine code for an CopyFromReg node or an
+/// implicit physical register output.
+void InstrEmitter::
+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;
+ EVT 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 = 0;
+ if (i+II.getNumDefs() < II.getNumOperands())
+ RC = II.OpInfo[i+II.getNumDefs()].getRegClass(TRI);
+ if (!UseRC)
+ UseRC = RC;
+ else if (RC) {
+ const TargetRegisterClass *ComRC = getCommonSubClass(UseRC, RC);
+ // If multiple uses expect disjoint register classes, we emit
+ // copies in AddRegisterOperand.
+ if (ComRC)
+ UseRC = ComRC;
+ }
+ }
+ }
+ }
+ MatchReg &= Match;
+ if (VRBase)
+ break;
+ }
+
+ EVT 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(*MBB, InsertPos, VRBase, SrcReg,
+ DstRC, SrcRC);
+
+ assert(Emitted && "Unable to issue a copy instruction!\n");
+ (void) Emitted;
+ }
+
+ 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 InstrEmitter::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 InstrEmitter::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 = II.OpInfo[i].getRegClass(TRI);
+ if (II.OpInfo[i].isOptionalDef()) {
+ // Optional def must be a physical register.
+ unsigned NumResults = CountResults(Node);
+ VRBase = cast<RegisterSDNode>(Node->getOperand(i-NumResults))->getReg();
+ assert(TargetRegisterInfo::isPhysicalRegister(VRBase));
+ MI->addOperand(MachineOperand::CreateReg(VRBase, true));
+ }
+
+ if (!VRBase && !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 InstrEmitter::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(MBB, 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
+InstrEmitter::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 = 0;
+ if (IIOpNum < II->getNumOperands())
+ DstRC = II->OpInfo[IIOpNum].getRegClass(TRI);
+ 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(*MBB, InsertPos, NewVReg, VReg,
+ DstRC, SrcRC);
+ assert(Emitted && "Unable to issue a copy instruction!\n");
+ (void) Emitted;
+ 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 InstrEmitter::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->getSExtValue()));
+ } 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(),
+ TGA->getTargetFlags()));
+ } 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(),
+ JT->getTargetFlags()));
+ } 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()->getTypeAllocSize(Type);
+ }
+ }
+
+ unsigned Idx;
+ MachineConstantPool *MCP = MF->getConstantPool();
+ if (CP->isMachineConstantPoolEntry())
+ Idx = MCP->getConstantPoolIndex(CP->getMachineCPVal(), Align);
+ else
+ Idx = MCP->getConstantPoolIndex(CP->getConstVal(), Align);
+ MI->addOperand(MachineOperand::CreateCPI(Idx, Offset,
+ CP->getTargetFlags()));
+ } else if (ExternalSymbolSDNode *ES = dyn_cast<ExternalSymbolSDNode>(Op)) {
+ MI->addOperand(MachineOperand::CreateES(ES->getSymbol(),
+ ES->getTargetFlags()));
+ } 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);
+ }
+}
+
+/// 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, EVT 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) && (*I)->getSubRegisterRegClass(SubIdx) == TRC)
+ return *I;
+ assert(false && "Couldn't find the register class");
+ return 0;
+}
+
+/// EmitSubregNode - Generate machine code for subreg nodes.
+///
+void InstrEmitter::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 = TRC->getSubRegisterRegClass(SubIdx);
+ assert(SRC && "Invalid subregister index in EXTRACT_SUBREG");
+
+ // 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));
+ MBB->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));
+ MBB->insert(InsertPos, MI);
+ } else
+ llvm_unreachable("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
+InstrEmitter::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(*MBB, InsertPos, NewVReg, VReg,
+ DstRC, SrcRC);
+ assert(Emitted &&
+ "Unable to issue a copy instruction for a COPY_TO_REGCLASS node!\n");
+ (void) Emitted;
+
+ 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 InstrEmitter::EmitNode(SDNode *Node, bool IsClone, bool IsCloned,
+ DenseMap<SDValue, unsigned> &VRBaseMap,
+ DenseMap<MachineBasicBlock*, MachineBasicBlock*> *EM) {
+ // 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);
+ 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.
+ bool HasOptPRefs = II.getNumDefs() > NumResults;
+ assert((!HasOptPRefs || !HasPhysRegOuts) &&
+ "Unable to cope with optional defs and phys regs defs!");
+ unsigned NumSkip = HasOptPRefs ? II.getNumDefs() - NumResults : 0;
+ for (unsigned i = NumSkip; i != NodeOperands; ++i)
+ AddOperand(MI, Node->getOperand(i), i-NumSkip+II.getNumDefs(), &II,
+ VRBaseMap);
+
+ // Transfer all of the memory reference descriptions of this instruction.
+ MI->setMemRefs(cast<MachineSDNode>(Node)->memoperands_begin(),
+ cast<MachineSDNode>(Node)->memoperands_end());
+
+ if (II.usesCustomDAGSchedInsertionHook()) {
+ // Insert this instruction into the basic block using a target
+ // specific inserter which may returns a new basic block.
+ MBB = TLI->EmitInstrWithCustomInserter(MI, MBB, EM);
+ InsertPos = MBB->end();
+ } else {
+ MBB->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();
+#endif
+ llvm_unreachable("This target-independent node should have been selected!");
+ break;
+ case ISD::EntryToken:
+ llvm_unreachable("EntryToken should have been excluded from the schedule!");
+ break;
+ case ISD::MERGE_VALUES:
+ 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(*MBB, InsertPos, DestReg, SrcReg,
+ DstTRC, SrcTRC);
+ assert(Emitted && "Unable to issue a copy instruction!\n");
+ (void) Emitted;
+ 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: llvm_unreachable("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, false, 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;
+ }
+ }
+ MBB->insert(InsertPos, MI);
+ break;
+ }
+ }
+}
+
+/// InstrEmitter - Construct an InstrEmitter and set it to start inserting
+/// at the given position in the given block.
+InstrEmitter::InstrEmitter(MachineBasicBlock *mbb,
+ MachineBasicBlock::iterator insertpos)
+ : MF(mbb->getParent()),
+ MRI(&MF->getRegInfo()),
+ TM(&MF->getTarget()),
+ TII(TM->getInstrInfo()),
+ TRI(TM->getRegisterInfo()),
+ TLI(TM->getTargetLowering()),
+ MBB(mbb), InsertPos(insertpos) {
+}