llvm-6502/lib/Target/ARM/ARMExpandPseudoInsts.cpp
2010-08-06 18:33:48 +00:00

183 lines
6.6 KiB
C++

//===-- ARMExpandPseudoInsts.cpp - Expand pseudo instructions -----*- C++ -*-=//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains a pass that expand pseudo instructions into target
// instructions to allow proper scheduling, if-conversion, and other late
// optimizations. This pass should be run after register allocation but before
// post- regalloc scheduling pass.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "arm-pseudo"
#include "ARM.h"
#include "ARMBaseInstrInfo.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/Target/TargetRegisterInfo.h"
using namespace llvm;
namespace {
class ARMExpandPseudo : public MachineFunctionPass {
public:
static char ID;
ARMExpandPseudo() : MachineFunctionPass(ID) {}
const TargetInstrInfo *TII;
const TargetRegisterInfo *TRI;
virtual bool runOnMachineFunction(MachineFunction &Fn);
virtual const char *getPassName() const {
return "ARM pseudo instruction expansion pass";
}
private:
void TransferImpOps(MachineInstr &OldMI,
MachineInstrBuilder &UseMI, MachineInstrBuilder &DefMI);
bool ExpandMBB(MachineBasicBlock &MBB);
};
char ARMExpandPseudo::ID = 0;
}
/// TransferImpOps - Transfer implicit operands on the pseudo instruction to
/// the instructions created from the expansion.
void ARMExpandPseudo::TransferImpOps(MachineInstr &OldMI,
MachineInstrBuilder &UseMI,
MachineInstrBuilder &DefMI) {
const TargetInstrDesc &Desc = OldMI.getDesc();
for (unsigned i = Desc.getNumOperands(), e = OldMI.getNumOperands();
i != e; ++i) {
const MachineOperand &MO = OldMI.getOperand(i);
assert(MO.isReg() && MO.getReg());
if (MO.isUse())
UseMI.addReg(MO.getReg(), getKillRegState(MO.isKill()));
else
DefMI.addReg(MO.getReg(),
getDefRegState(true) | getDeadRegState(MO.isDead()));
}
}
bool ARMExpandPseudo::ExpandMBB(MachineBasicBlock &MBB) {
bool Modified = false;
MachineBasicBlock::iterator MBBI = MBB.begin(), E = MBB.end();
while (MBBI != E) {
MachineInstr &MI = *MBBI;
MachineBasicBlock::iterator NMBBI = llvm::next(MBBI);
unsigned Opcode = MI.getOpcode();
switch (Opcode) {
default: break;
case ARM::tLDRpci_pic:
case ARM::t2LDRpci_pic: {
unsigned NewLdOpc = (Opcode == ARM::tLDRpci_pic)
? ARM::tLDRpci : ARM::t2LDRpci;
unsigned DstReg = MI.getOperand(0).getReg();
bool DstIsDead = MI.getOperand(0).isDead();
MachineInstrBuilder MIB1 =
AddDefaultPred(BuildMI(MBB, MBBI, MI.getDebugLoc(),
TII->get(NewLdOpc), DstReg)
.addOperand(MI.getOperand(1)));
(*MIB1).setMemRefs(MI.memoperands_begin(), MI.memoperands_end());
MachineInstrBuilder MIB2 = BuildMI(MBB, MBBI, MI.getDebugLoc(),
TII->get(ARM::tPICADD))
.addReg(DstReg, getDefRegState(true) | getDeadRegState(DstIsDead))
.addReg(DstReg)
.addOperand(MI.getOperand(2));
TransferImpOps(MI, MIB1, MIB2);
MI.eraseFromParent();
Modified = true;
break;
}
case ARM::t2MOVi32imm: {
unsigned PredReg = 0;
ARMCC::CondCodes Pred = llvm::getInstrPredicate(&MI, PredReg);
unsigned DstReg = MI.getOperand(0).getReg();
bool DstIsDead = MI.getOperand(0).isDead();
const MachineOperand &MO = MI.getOperand(1);
MachineInstrBuilder LO16, HI16;
LO16 = BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(ARM::t2MOVi16),
DstReg);
HI16 = BuildMI(MBB, MBBI, MI.getDebugLoc(), TII->get(ARM::t2MOVTi16))
.addReg(DstReg, getDefRegState(true) | getDeadRegState(DstIsDead))
.addReg(DstReg);
if (MO.isImm()) {
unsigned Imm = MO.getImm();
unsigned Lo16 = Imm & 0xffff;
unsigned Hi16 = (Imm >> 16) & 0xffff;
LO16 = LO16.addImm(Lo16);
HI16 = HI16.addImm(Hi16);
} else {
const GlobalValue *GV = MO.getGlobal();
unsigned TF = MO.getTargetFlags();
LO16 = LO16.addGlobalAddress(GV, MO.getOffset(), TF | ARMII::MO_LO16);
HI16 = HI16.addGlobalAddress(GV, MO.getOffset(), TF | ARMII::MO_HI16);
}
(*LO16).setMemRefs(MI.memoperands_begin(), MI.memoperands_end());
(*HI16).setMemRefs(MI.memoperands_begin(), MI.memoperands_end());
LO16.addImm(Pred).addReg(PredReg);
HI16.addImm(Pred).addReg(PredReg);
TransferImpOps(MI, LO16, HI16);
MI.eraseFromParent();
Modified = true;
break;
}
case ARM::VMOVQQ: {
unsigned DstReg = MI.getOperand(0).getReg();
bool DstIsDead = MI.getOperand(0).isDead();
unsigned EvenDst = TRI->getSubReg(DstReg, ARM::qsub_0);
unsigned OddDst = TRI->getSubReg(DstReg, ARM::qsub_1);
unsigned SrcReg = MI.getOperand(1).getReg();
bool SrcIsKill = MI.getOperand(1).isKill();
unsigned EvenSrc = TRI->getSubReg(SrcReg, ARM::qsub_0);
unsigned OddSrc = TRI->getSubReg(SrcReg, ARM::qsub_1);
MachineInstrBuilder Even =
AddDefaultPred(BuildMI(MBB, MBBI, MI.getDebugLoc(),
TII->get(ARM::VMOVQ))
.addReg(EvenDst,
getDefRegState(true) | getDeadRegState(DstIsDead))
.addReg(EvenSrc, getKillRegState(SrcIsKill)));
MachineInstrBuilder Odd =
AddDefaultPred(BuildMI(MBB, MBBI, MI.getDebugLoc(),
TII->get(ARM::VMOVQ))
.addReg(OddDst,
getDefRegState(true) | getDeadRegState(DstIsDead))
.addReg(OddSrc, getKillRegState(SrcIsKill)));
TransferImpOps(MI, Even, Odd);
MI.eraseFromParent();
Modified = true;
}
}
MBBI = NMBBI;
}
return Modified;
}
bool ARMExpandPseudo::runOnMachineFunction(MachineFunction &MF) {
TII = MF.getTarget().getInstrInfo();
TRI = MF.getTarget().getRegisterInfo();
bool Modified = false;
for (MachineFunction::iterator MFI = MF.begin(), E = MF.end(); MFI != E;
++MFI)
Modified |= ExpandMBB(*MFI);
return Modified;
}
/// createARMExpandPseudoPass - returns an instance of the pseudo instruction
/// expansion pass.
FunctionPass *llvm::createARMExpandPseudoPass() {
return new ARMExpandPseudo();
}