-//===- Thumb2InstrInfo.cpp - Thumb-2 Instruction Information --------*- C++ -*-===//
+//===- Thumb2InstrInfo.cpp - Thumb-2 Instruction Information ----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
//
//===----------------------------------------------------------------------===//
-#include "ARMInstrInfo.h"
+#include "Thumb2InstrInfo.h"
#include "ARM.h"
+#include "ARMConstantPoolValue.h"
#include "ARMAddressingModes.h"
#include "ARMGenInstrInfo.inc"
#include "ARMMachineFunctionInfo.h"
+#include "Thumb2HazardRecognizer.h"
+#include "Thumb2InstrInfo.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineMemOperand.h"
+#include "llvm/CodeGen/PseudoSourceValue.h"
#include "llvm/ADT/SmallVector.h"
-#include "Thumb2InstrInfo.h"
+#include "llvm/Support/CommandLine.h"
using namespace llvm;
-Thumb2InstrInfo::Thumb2InstrInfo(const ARMSubtarget &STI) : RI(*this, STI) {
+static cl::opt<unsigned>
+IfCvtLimit("thumb2-ifcvt-limit", cl::Hidden,
+ cl::desc("Thumb2 if-conversion limit (default 3)"),
+ cl::init(3));
+
+static cl::opt<unsigned>
+IfCvtDiamondLimit("thumb2-ifcvt-diamond-limit", cl::Hidden,
+ cl::desc("Thumb2 diamond if-conversion limit (default 3)"),
+ cl::init(3));
+
+Thumb2InstrInfo::Thumb2InstrInfo(const ARMSubtarget &STI)
+ : ARMBaseInstrInfo(STI), RI(*this, STI) {
}
unsigned Thumb2InstrInfo::getUnindexedOpcode(unsigned Opc) const {
return 0;
}
-bool
-Thumb2InstrInfo::BlockHasNoFallThrough(const MachineBasicBlock &MBB) const {
- if (MBB.empty()) return false;
-
- switch (MBB.back().getOpcode()) {
- case ARM::t2LDM_RET:
- case ARM::t2B: // Uncond branch.
- case ARM::t2BR_JT: // Jumptable branch.
- case ARM::t2TBB: // Table branch byte.
- case ARM::t2TBH: // Table branch halfword.
- case ARM::tBR_JTr: // Jumptable branch (16-bit version).
- case ARM::tBX_RET:
- case ARM::tBX_RET_vararg:
- case ARM::tPOP_RET:
- case ARM::tB:
- return true;
- default:
- break;
+void
+Thumb2InstrInfo::ReplaceTailWithBranchTo(MachineBasicBlock::iterator Tail,
+ MachineBasicBlock *NewDest) const {
+ MachineBasicBlock *MBB = Tail->getParent();
+ ARMFunctionInfo *AFI = MBB->getParent()->getInfo<ARMFunctionInfo>();
+ if (!AFI->hasITBlocks()) {
+ TargetInstrInfoImpl::ReplaceTailWithBranchTo(Tail, NewDest);
+ return;
}
- return false;
+ // If the first instruction of Tail is predicated, we may have to update
+ // the IT instruction.
+ unsigned PredReg = 0;
+ ARMCC::CondCodes CC = llvm::getInstrPredicate(Tail, PredReg);
+ MachineBasicBlock::iterator MBBI = Tail;
+ if (CC != ARMCC::AL)
+ // Expecting at least the t2IT instruction before it.
+ --MBBI;
+
+ // Actually replace the tail.
+ TargetInstrInfoImpl::ReplaceTailWithBranchTo(Tail, NewDest);
+
+ // Fix up IT.
+ if (CC != ARMCC::AL) {
+ MachineBasicBlock::iterator E = MBB->begin();
+ unsigned Count = 4; // At most 4 instructions in an IT block.
+ while (Count && MBBI != E) {
+ if (MBBI->isDebugValue()) {
+ --MBBI;
+ continue;
+ }
+ if (MBBI->getOpcode() == ARM::t2IT) {
+ unsigned Mask = MBBI->getOperand(1).getImm();
+ if (Count == 4)
+ MBBI->eraseFromParent();
+ else {
+ unsigned MaskOn = 1 << Count;
+ unsigned MaskOff = ~(MaskOn - 1);
+ MBBI->getOperand(1).setImm((Mask & MaskOff) | MaskOn);
+ }
+ return;
+ }
+ --MBBI;
+ --Count;
+ }
+
+ // Ctrl flow can reach here if branch folding is run before IT block
+ // formation pass.
+ }
}
bool
-Thumb2InstrInfo::copyRegToReg(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator I,
- unsigned DestReg, unsigned SrcReg,
- const TargetRegisterClass *DestRC,
- const TargetRegisterClass *SrcRC) const {
- DebugLoc DL = DebugLoc::getUnknownLoc();
- if (I != MBB.end()) DL = I->getDebugLoc();
-
- if (DestRC == ARM::GPRRegisterClass &&
- SrcRC == ARM::GPRRegisterClass) {
- BuildMI(MBB, I, DL, get(ARM::tMOVgpr2gpr), DestReg).addReg(SrcReg);
- return true;
- } else if (DestRC == ARM::GPRRegisterClass &&
- SrcRC == ARM::tGPRRegisterClass) {
- BuildMI(MBB, I, DL, get(ARM::tMOVtgpr2gpr), DestReg).addReg(SrcReg);
- return true;
- } else if (DestRC == ARM::tGPRRegisterClass &&
- SrcRC == ARM::GPRRegisterClass) {
- BuildMI(MBB, I, DL, get(ARM::tMOVgpr2tgpr), DestReg).addReg(SrcReg);
- return true;
- }
+Thumb2InstrInfo::isLegalToSplitMBBAt(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MBBI) const {
+ unsigned PredReg = 0;
+ return llvm::getITInstrPredicate(MBBI, PredReg) == ARMCC::AL;
+}
+
+bool Thumb2InstrInfo::isProfitableToIfCvt(MachineBasicBlock &MBB,
+ unsigned NumInstrs) const {
+ return NumInstrs && NumInstrs <= IfCvtLimit;
+}
+
+bool Thumb2InstrInfo::
+isProfitableToIfCvt(MachineBasicBlock &TMBB, unsigned NumT,
+ MachineBasicBlock &FMBB, unsigned NumF) const {
+ // FIXME: Catch optimization such as:
+ // r0 = movne
+ // r0 = moveq
+ return NumT && NumF &&
+ NumT <= (IfCvtDiamondLimit) && NumF <= (IfCvtDiamondLimit);
+}
+void Thumb2InstrInfo::copyPhysReg(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator I, DebugLoc DL,
+ unsigned DestReg, unsigned SrcReg,
+ bool KillSrc) const {
// Handle SPR, DPR, and QPR copies.
- return ARMBaseInstrInfo::copyRegToReg(MBB, I, DestReg, SrcReg, DestRC, SrcRC);
+ if (!ARM::GPRRegClass.contains(DestReg, SrcReg))
+ return ARMBaseInstrInfo::copyPhysReg(MBB, I, DL, DestReg, SrcReg, KillSrc);
+
+ bool tDest = ARM::tGPRRegClass.contains(DestReg);
+ bool tSrc = ARM::tGPRRegClass.contains(SrcReg);
+ unsigned Opc = ARM::tMOVgpr2gpr;
+ if (tDest && tSrc)
+ Opc = ARM::tMOVr;
+ else if (tSrc)
+ Opc = ARM::tMOVtgpr2gpr;
+ else if (tDest)
+ Opc = ARM::tMOVgpr2tgpr;
+
+ BuildMI(MBB, I, DL, get(Opc), DestReg)
+ .addReg(SrcReg, getKillRegState(KillSrc));
}
void Thumb2InstrInfo::
storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned SrcReg, bool isKill, int FI,
- const TargetRegisterClass *RC) const {
- DebugLoc DL = DebugLoc::getUnknownLoc();
- if (I != MBB.end()) DL = I->getDebugLoc();
-
- if (RC == ARM::GPRRegisterClass) {
+ const TargetRegisterClass *RC,
+ const TargetRegisterInfo *TRI) const {
+ if (RC == ARM::GPRRegisterClass || RC == ARM::tGPRRegisterClass ||
+ RC == ARM::tcGPRRegisterClass || RC == ARM::rGPRRegisterClass) {
+ DebugLoc DL;
+ if (I != MBB.end()) DL = I->getDebugLoc();
+
+ MachineFunction &MF = *MBB.getParent();
+ MachineFrameInfo &MFI = *MF.getFrameInfo();
+ MachineMemOperand *MMO =
+ MF.getMachineMemOperand(PseudoSourceValue::getFixedStack(FI),
+ MachineMemOperand::MOStore, 0,
+ MFI.getObjectSize(FI),
+ MFI.getObjectAlignment(FI));
AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::t2STRi12))
.addReg(SrcReg, getKillRegState(isKill))
- .addFrameIndex(FI).addImm(0));
+ .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
return;
}
- ARMBaseInstrInfo::storeRegToStackSlot(MBB, I, SrcReg, isKill, FI, RC);
+ ARMBaseInstrInfo::storeRegToStackSlot(MBB, I, SrcReg, isKill, FI, RC, TRI);
}
void Thumb2InstrInfo::
loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned DestReg, int FI,
- const TargetRegisterClass *RC) const {
- DebugLoc DL = DebugLoc::getUnknownLoc();
- if (I != MBB.end()) DL = I->getDebugLoc();
-
- if (RC == ARM::GPRRegisterClass) {
+ const TargetRegisterClass *RC,
+ const TargetRegisterInfo *TRI) const {
+ if (RC == ARM::GPRRegisterClass || RC == ARM::tGPRRegisterClass ||
+ RC == ARM::tcGPRRegisterClass || RC == ARM::rGPRRegisterClass) {
+ DebugLoc DL;
+ if (I != MBB.end()) DL = I->getDebugLoc();
+
+ MachineFunction &MF = *MBB.getParent();
+ MachineFrameInfo &MFI = *MF.getFrameInfo();
+ MachineMemOperand *MMO =
+ MF.getMachineMemOperand(PseudoSourceValue::getFixedStack(FI),
+ MachineMemOperand::MOLoad, 0,
+ MFI.getObjectSize(FI),
+ MFI.getObjectAlignment(FI));
AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::t2LDRi12), DestReg)
- .addFrameIndex(FI).addImm(0));
+ .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
return;
}
- ARMBaseInstrInfo::loadRegFromStackSlot(MBB, I, DestReg, FI, RC);
+ ARMBaseInstrInfo::loadRegFromStackSlot(MBB, I, DestReg, FI, RC, TRI);
}
+ScheduleHazardRecognizer *Thumb2InstrInfo::
+CreateTargetPostRAHazardRecognizer(const InstrItineraryData &II) const {
+ return (ScheduleHazardRecognizer *)new Thumb2HazardRecognizer(II);
+}
void llvm::emitT2RegPlusImmediate(MachineBasicBlock &MBB,
MachineBasicBlock::iterator &MBBI, DebugLoc dl,
// Use a movw to materialize the 16-bit constant.
BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVi16), DestReg)
.addImm(NumBytes)
- .addImm((unsigned)Pred).addReg(PredReg).addReg(0);
+ .addImm((unsigned)Pred).addReg(PredReg);
Fits = true;
} else if ((NumBytes & 0xffff) == 0) {
// Use a movt to materialize the 32-bit constant.
BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVTi16), DestReg)
.addReg(DestReg)
.addImm(NumBytes >> 16)
- .addImm((unsigned)Pred).addReg(PredReg).addReg(0);
+ .addImm((unsigned)Pred).addReg(PredReg);
Fits = true;
}
continue;
}
+ bool HasCCOut = true;
if (BaseReg == ARM::SP) {
// sub sp, sp, #imm7
if (DestReg == ARM::SP && (ThisVal < ((1 << 7)-1) * 4)) {
NumBytes = 0;
} else if (ThisVal < 4096) {
Opc = isSub ? ARM::t2SUBri12 : ARM::t2ADDri12;
+ HasCCOut = false;
NumBytes = 0;
} else {
// FIXME: Move this to ARMAddressingModes.h?
}
// Build the new ADD / SUB.
- AddDefaultCC(AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
- .addReg(BaseReg, RegState::Kill)
- .addImm(ThisVal)));
+ MachineInstrBuilder MIB =
+ AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
+ .addReg(BaseReg, RegState::Kill)
+ .addImm(ThisVal));
+ if (HasCCOut)
+ AddDefaultCC(MIB);
BaseReg = DestReg;
}
if (Opcode == ARM::t2ADDri || Opcode == ARM::t2ADDri12) {
Offset += MI.getOperand(FrameRegIdx+1).getImm();
- bool isSP = FrameReg == ARM::SP;
- if (Offset == 0) {
+ unsigned PredReg;
+ if (Offset == 0 && getInstrPredicate(&MI, PredReg) == ARMCC::AL) {
// Turn it into a move.
MI.setDesc(TII.get(ARM::tMOVgpr2gpr));
MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
- MI.RemoveOperand(FrameRegIdx+1);
- Offset = 0;
+ // Remove offset and remaining explicit predicate operands.
+ do MI.RemoveOperand(FrameRegIdx+1);
+ while (MI.getNumOperands() > FrameRegIdx+1 &&
+ (!MI.getOperand(FrameRegIdx+1).isReg() ||
+ !MI.getOperand(FrameRegIdx+1).isImm()));
return true;
}
+ bool isSP = FrameReg == ARM::SP;
+ bool HasCCOut = Opcode != ARM::t2ADDri12;
+
if (Offset < 0) {
Offset = -Offset;
isSub = true;
if (ARM_AM::getT2SOImmVal(Offset) != -1) {
MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
+ // Add cc_out operand if the original instruction did not have one.
+ if (!HasCCOut)
+ MI.addOperand(MachineOperand::CreateReg(0, false));
Offset = 0;
return true;
}
// Another common case: imm12.
- if (Offset < 4096) {
+ if (Offset < 4096 &&
+ (!HasCCOut || MI.getOperand(MI.getNumOperands()-1).getReg() == 0)) {
unsigned NewOpc = isSP
? (isSub ? ARM::t2SUBrSPi12 : ARM::t2ADDrSPi12)
: (isSub ? ARM::t2SUBri12 : ARM::t2ADDri12);
MI.setDesc(TII.get(NewOpc));
MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
+ // Remove the cc_out operand.
+ if (HasCCOut)
+ MI.RemoveOperand(MI.getNumOperands()-1);
Offset = 0;
return true;
}
assert(ARM_AM::getT2SOImmVal(ThisImmVal) != -1 &&
"Bit extraction didn't work?");
MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal);
+ // Add cc_out operand if the original instruction did not have one.
+ if (!HasCCOut)
+ MI.addOperand(MachineOperand::CreateReg(0, false));
+
} else {
- // AddrMode4 cannot handle any offset.
- if (AddrMode == ARMII::AddrMode4)
+ // AddrMode4 and AddrMode6 cannot handle any offset.
+ if (AddrMode == ARMII::AddrMode4 || AddrMode == ARMII::AddrMode6)
return false;
// AddrModeT2_so cannot handle any offset. If there is no offset
NewOpc = positiveOffsetOpcode(Opcode);
NumBits = 12;
}
- } else {
- // VFP and NEON address modes.
- int InstrOffs = 0;
- if (AddrMode == ARMII::AddrMode5) {
- const MachineOperand &OffOp = MI.getOperand(FrameRegIdx+1);
- InstrOffs = ARM_AM::getAM5Offset(OffOp.getImm());
- if (ARM_AM::getAM5Op(OffOp.getImm()) == ARM_AM::sub)
- InstrOffs *= -1;
- }
+ } else if (AddrMode == ARMII::AddrMode5) {
+ // VFP address mode.
+ const MachineOperand &OffOp = MI.getOperand(FrameRegIdx+1);
+ int InstrOffs = ARM_AM::getAM5Offset(OffOp.getImm());
+ if (ARM_AM::getAM5Op(OffOp.getImm()) == ARM_AM::sub)
+ InstrOffs *= -1;
NumBits = 8;
Scale = 4;
Offset += InstrOffs * 4;
Offset = -Offset;
isSub = true;
}
+ } else {
+ llvm_unreachable("Unsupported addressing mode!");
}
if (NewOpc != Opcode)
Offset = (isSub) ? -Offset : Offset;
return Offset == 0;
}
+
+/// scheduleTwoAddrSource - Schedule the copy / re-mat of the source of the
+/// two-addrss instruction inserted by two-address pass.
+void
+Thumb2InstrInfo::scheduleTwoAddrSource(MachineInstr *SrcMI,
+ MachineInstr *UseMI,
+ const TargetRegisterInfo &TRI) const {
+ if (SrcMI->getOpcode() != ARM::tMOVgpr2gpr ||
+ SrcMI->getOperand(1).isKill())
+ return;
+
+ unsigned PredReg = 0;
+ ARMCC::CondCodes CC = llvm::getInstrPredicate(UseMI, PredReg);
+ if (CC == ARMCC::AL || PredReg != ARM::CPSR)
+ return;
+
+ // Schedule the copy so it doesn't come between previous instructions
+ // and UseMI which can form an IT block.
+ unsigned SrcReg = SrcMI->getOperand(1).getReg();
+ ARMCC::CondCodes OCC = ARMCC::getOppositeCondition(CC);
+ MachineBasicBlock *MBB = UseMI->getParent();
+ MachineBasicBlock::iterator MBBI = SrcMI;
+ unsigned NumInsts = 0;
+ while (--MBBI != MBB->begin()) {
+ if (MBBI->isDebugValue())
+ continue;
+
+ MachineInstr *NMI = &*MBBI;
+ ARMCC::CondCodes NCC = llvm::getInstrPredicate(NMI, PredReg);
+ if (!(NCC == CC || NCC == OCC) ||
+ NMI->modifiesRegister(SrcReg, &TRI) ||
+ NMI->definesRegister(ARM::CPSR))
+ break;
+ if (++NumInsts == 4)
+ // Too many in a row!
+ return;
+ }
+
+ if (NumInsts) {
+ MBB->remove(SrcMI);
+ MBB->insert(++MBBI, SrcMI);
+ }
+}
+
+ARMCC::CondCodes
+llvm::getITInstrPredicate(const MachineInstr *MI, unsigned &PredReg) {
+ unsigned Opc = MI->getOpcode();
+ if (Opc == ARM::tBcc || Opc == ARM::t2Bcc)
+ return ARMCC::AL;
+ return llvm::getInstrPredicate(MI, PredReg);
+}