diff options
Diffstat (limited to 'lib/CodeGen/TargetInstrInfoImpl.cpp')
| -rw-r--r-- | lib/CodeGen/TargetInstrInfoImpl.cpp | 194 | 
1 files changed, 194 insertions, 0 deletions
diff --git a/lib/CodeGen/TargetInstrInfoImpl.cpp b/lib/CodeGen/TargetInstrInfoImpl.cpp new file mode 100644 index 000000000000..a5e1ee435529 --- /dev/null +++ b/lib/CodeGen/TargetInstrInfoImpl.cpp @@ -0,0 +1,194 @@ +//===-- TargetInstrInfoImpl.cpp - Target Instruction Information ----------===// +// +//                     The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements the TargetInstrInfoImpl class, it just provides default +// implementations of various methods. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Target/TargetInstrInfo.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/CodeGen/MachineFrameInfo.h" +#include "llvm/CodeGen/MachineInstr.h" +#include "llvm/CodeGen/MachineInstrBuilder.h" +#include "llvm/CodeGen/PseudoSourceValue.h" +using namespace llvm; + +// commuteInstruction - The default implementation of this method just exchanges +// operand 1 and 2. +MachineInstr *TargetInstrInfoImpl::commuteInstruction(MachineInstr *MI, +                                                      bool NewMI) const { +  assert(MI->getOperand(1).isReg() && MI->getOperand(2).isReg() && +         "This only knows how to commute register operands so far"); +  unsigned Reg1 = MI->getOperand(1).getReg(); +  unsigned Reg2 = MI->getOperand(2).getReg(); +  bool Reg1IsKill = MI->getOperand(1).isKill(); +  bool Reg2IsKill = MI->getOperand(2).isKill(); +  bool ChangeReg0 = false; +  if (MI->getOperand(0).getReg() == Reg1) { +    // Must be two address instruction! +    assert(MI->getDesc().getOperandConstraint(0, TOI::TIED_TO) && +           "Expecting a two-address instruction!"); +    Reg2IsKill = false; +    ChangeReg0 = true; +  } + +  if (NewMI) { +    // Create a new instruction. +    unsigned Reg0 = ChangeReg0 ? Reg2 : MI->getOperand(0).getReg(); +    bool Reg0IsDead = MI->getOperand(0).isDead(); +    MachineFunction &MF = *MI->getParent()->getParent(); +    return BuildMI(MF, MI->getDebugLoc(), MI->getDesc()) +      .addReg(Reg0, RegState::Define | getDeadRegState(Reg0IsDead)) +      .addReg(Reg2, getKillRegState(Reg2IsKill)) +      .addReg(Reg1, getKillRegState(Reg2IsKill)); +  } + +  if (ChangeReg0) +    MI->getOperand(0).setReg(Reg2); +  MI->getOperand(2).setReg(Reg1); +  MI->getOperand(1).setReg(Reg2); +  MI->getOperand(2).setIsKill(Reg1IsKill); +  MI->getOperand(1).setIsKill(Reg2IsKill); +  return MI; +} + +/// CommuteChangesDestination - Return true if commuting the specified +/// instruction will also changes the destination operand. Also return the +/// current operand index of the would be new destination register by +/// reference. This can happen when the commutable instruction is also a +/// two-address instruction. +bool TargetInstrInfoImpl::CommuteChangesDestination(MachineInstr *MI, +                                                    unsigned &OpIdx) const{ +  assert(MI->getOperand(1).isReg() && MI->getOperand(2).isReg() && +         "This only knows how to commute register operands so far"); +  if (MI->getOperand(0).getReg() == MI->getOperand(1).getReg()) { +    // Must be two address instruction! +    assert(MI->getDesc().getOperandConstraint(0, TOI::TIED_TO) && +           "Expecting a two-address instruction!"); +    OpIdx = 2; +    return true; +  } +  return false; +} + + +bool TargetInstrInfoImpl::PredicateInstruction(MachineInstr *MI, +                            const SmallVectorImpl<MachineOperand> &Pred) const { +  bool MadeChange = false; +  const TargetInstrDesc &TID = MI->getDesc(); +  if (!TID.isPredicable()) +    return false; +   +  for (unsigned j = 0, i = 0, e = MI->getNumOperands(); i != e; ++i) { +    if (TID.OpInfo[i].isPredicate()) { +      MachineOperand &MO = MI->getOperand(i); +      if (MO.isReg()) { +        MO.setReg(Pred[j].getReg()); +        MadeChange = true; +      } else if (MO.isImm()) { +        MO.setImm(Pred[j].getImm()); +        MadeChange = true; +      } else if (MO.isMBB()) { +        MO.setMBB(Pred[j].getMBB()); +        MadeChange = true; +      } +      ++j; +    } +  } +  return MadeChange; +} + +void TargetInstrInfoImpl::reMaterialize(MachineBasicBlock &MBB, +                                        MachineBasicBlock::iterator I, +                                        unsigned DestReg, +                                        const MachineInstr *Orig) const { +  MachineInstr *MI = MBB.getParent()->CloneMachineInstr(Orig); +  MI->getOperand(0).setReg(DestReg); +  MBB.insert(I, MI); +} + +unsigned +TargetInstrInfoImpl::GetFunctionSizeInBytes(const MachineFunction &MF) const { +  unsigned FnSize = 0; +  for (MachineFunction::const_iterator MBBI = MF.begin(), E = MF.end(); +       MBBI != E; ++MBBI) { +    const MachineBasicBlock &MBB = *MBBI; +    for (MachineBasicBlock::const_iterator I = MBB.begin(),E = MBB.end(); +         I != E; ++I) +      FnSize += GetInstSizeInBytes(I); +  } +  return FnSize; +} + +/// foldMemoryOperand - Attempt to fold a load or store of the specified stack +/// slot into the specified machine instruction for the specified operand(s). +/// If this is possible, a new instruction is returned with the specified +/// operand folded, otherwise NULL is returned. The client is responsible for +/// removing the old instruction and adding the new one in the instruction +/// stream. +MachineInstr* +TargetInstrInfo::foldMemoryOperand(MachineFunction &MF, +                                   MachineInstr* MI, +                                   const SmallVectorImpl<unsigned> &Ops, +                                   int FrameIndex) const { +  unsigned Flags = 0; +  for (unsigned i = 0, e = Ops.size(); i != e; ++i) +    if (MI->getOperand(Ops[i]).isDef()) +      Flags |= MachineMemOperand::MOStore; +    else +      Flags |= MachineMemOperand::MOLoad; + +  // Ask the target to do the actual folding. +  MachineInstr *NewMI = foldMemoryOperandImpl(MF, MI, Ops, FrameIndex); +  if (!NewMI) return 0; + +  assert((!(Flags & MachineMemOperand::MOStore) || +          NewMI->getDesc().mayStore()) && +         "Folded a def to a non-store!"); +  assert((!(Flags & MachineMemOperand::MOLoad) || +          NewMI->getDesc().mayLoad()) && +         "Folded a use to a non-load!"); +  const MachineFrameInfo &MFI = *MF.getFrameInfo(); +  assert(MFI.getObjectOffset(FrameIndex) != -1); +  MachineMemOperand MMO(PseudoSourceValue::getFixedStack(FrameIndex), +                        Flags, +                        MFI.getObjectOffset(FrameIndex), +                        MFI.getObjectSize(FrameIndex), +                        MFI.getObjectAlignment(FrameIndex)); +  NewMI->addMemOperand(MF, MMO); + +  return NewMI; +} + +/// foldMemoryOperand - Same as the previous version except it allows folding +/// of any load and store from / to any address, not just from a specific +/// stack slot. +MachineInstr* +TargetInstrInfo::foldMemoryOperand(MachineFunction &MF, +                                   MachineInstr* MI, +                                   const SmallVectorImpl<unsigned> &Ops, +                                   MachineInstr* LoadMI) const { +  assert(LoadMI->getDesc().canFoldAsLoad() && "LoadMI isn't foldable!"); +#ifndef NDEBUG +  for (unsigned i = 0, e = Ops.size(); i != e; ++i) +    assert(MI->getOperand(Ops[i]).isUse() && "Folding load into def!"); +#endif + +  // Ask the target to do the actual folding. +  MachineInstr *NewMI = foldMemoryOperandImpl(MF, MI, Ops, LoadMI); +  if (!NewMI) return 0; + +  // Copy the memoperands from the load to the folded instruction. +  for (std::list<MachineMemOperand>::iterator I = LoadMI->memoperands_begin(), +       E = LoadMI->memoperands_end(); I != E; ++I) +    NewMI->addMemOperand(MF, *I); + +  return NewMI; +}  | 
