#define DEBUG_TYPE "arm-ldst-opt"
#include "ARM.h"
#include "ARMAddressingModes.h"
+#include "ARMBaseInstrInfo.h"
#include "ARMMachineFunctionInfo.h"
#include "ARMRegisterInfo.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/Statistic.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Function.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RegisterScavenging.h"
-#include "llvm/Support/Compiler.h"
-#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Statistic.h"
using namespace llvm;
STATISTIC(NumLDMGened , "Number of ldm instructions generated");
STATISTIC(NumSTMGened , "Number of stm instructions generated");
-STATISTIC(NumFLDMGened, "Number of fldm instructions generated");
-STATISTIC(NumFSTMGened, "Number of fstm instructions generated");
+STATISTIC(NumVLDMGened, "Number of vldm instructions generated");
+STATISTIC(NumVSTMGened, "Number of vstm instructions generated");
+STATISTIC(NumLdStMoved, "Number of load / store instructions moved");
+STATISTIC(NumLDRDFormed,"Number of ldrd created before allocation");
+STATISTIC(NumSTRDFormed,"Number of strd created before allocation");
+STATISTIC(NumLDRD2LDM, "Number of ldrd instructions turned back into ldm");
+STATISTIC(NumSTRD2STM, "Number of strd instructions turned back into stm");
+STATISTIC(NumLDRD2LDR, "Number of ldrd instructions turned back into ldr's");
+STATISTIC(NumSTRD2STR, "Number of strd instructions turned back into str's");
+
+/// ARMAllocLoadStoreOpt - Post- register allocation pass the combine
+/// load / store instructions to form ldm / stm instructions.
namespace {
- struct VISIBILITY_HIDDEN ARMLoadStoreOpt : public MachineFunctionPass {
+ struct ARMLoadStoreOpt : public MachineFunctionPass {
static char ID;
- ARMLoadStoreOpt() : MachineFunctionPass(&ID) {}
+ ARMLoadStoreOpt() : MachineFunctionPass(ID) {}
const TargetInstrInfo *TII;
const TargetRegisterInfo *TRI;
ARMFunctionInfo *AFI;
RegScavenger *RS;
+ bool isThumb2;
virtual bool runOnMachineFunction(MachineFunction &Fn);
private:
struct MemOpQueueEntry {
int Offset;
+ unsigned Reg;
+ bool isKill;
unsigned Position;
MachineBasicBlock::iterator MBBI;
bool Merged;
- MemOpQueueEntry(int o, int p, MachineBasicBlock::iterator i)
- : Offset(o), Position(p), MBBI(i), Merged(false) {};
+ MemOpQueueEntry(int o, unsigned r, bool k, unsigned p,
+ MachineBasicBlock::iterator i)
+ : Offset(o), Reg(r), isKill(k), Position(p), MBBI(i), Merged(false) {}
};
typedef SmallVector<MemOpQueueEntry,8> MemOpQueue;
typedef MemOpQueue::iterator MemOpQueueIter;
- SmallVector<MachineBasicBlock::iterator, 4>
- MergeLDR_STR(MachineBasicBlock &MBB, unsigned SIndex, unsigned Base,
- int Opcode, unsigned Size,
- ARMCC::CondCodes Pred, unsigned PredReg,
- unsigned Scratch, MemOpQueue &MemOps);
+ bool MergeOps(MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI,
+ int Offset, unsigned Base, bool BaseKill, int Opcode,
+ ARMCC::CondCodes Pred, unsigned PredReg, unsigned Scratch,
+ DebugLoc dl, SmallVector<std::pair<unsigned, bool>, 8> &Regs);
+ void MergeOpsUpdate(MachineBasicBlock &MBB,
+ MemOpQueue &MemOps,
+ unsigned memOpsBegin,
+ unsigned memOpsEnd,
+ unsigned insertAfter,
+ int Offset,
+ unsigned Base,
+ bool BaseKill,
+ int Opcode,
+ ARMCC::CondCodes Pred,
+ unsigned PredReg,
+ unsigned Scratch,
+ DebugLoc dl,
+ SmallVector<MachineBasicBlock::iterator, 4> &Merges);
+ void MergeLDR_STR(MachineBasicBlock &MBB, unsigned SIndex, unsigned Base,
+ int Opcode, unsigned Size,
+ ARMCC::CondCodes Pred, unsigned PredReg,
+ unsigned Scratch, MemOpQueue &MemOps,
+ SmallVector<MachineBasicBlock::iterator, 4> &Merges);
void AdvanceRS(MachineBasicBlock &MBB, MemOpQueue &MemOps);
+ bool FixInvalidRegPairOp(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &MBBI);
+ bool MergeBaseUpdateLoadStore(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MBBI,
+ const TargetInstrInfo *TII,
+ bool &Advance,
+ MachineBasicBlock::iterator &I);
+ bool MergeBaseUpdateLSMultiple(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MBBI,
+ bool &Advance,
+ MachineBasicBlock::iterator &I);
bool LoadStoreMultipleOpti(MachineBasicBlock &MBB);
bool MergeReturnIntoLDM(MachineBasicBlock &MBB);
};
char ARMLoadStoreOpt::ID = 0;
}
-/// createARMLoadStoreOptimizationPass - returns an instance of the load / store
-/// optimization pass.
-FunctionPass *llvm::createARMLoadStoreOptimizationPass() {
- return new ARMLoadStoreOpt();
-}
-
static int getLoadStoreMultipleOpcode(int Opcode) {
switch (Opcode) {
case ARM::LDR:
- NumLDMGened++;
+ ++NumLDMGened;
return ARM::LDM;
case ARM::STR:
- NumSTMGened++;
+ ++NumSTMGened;
return ARM::STM;
- case ARM::FLDS:
- NumFLDMGened++;
- return ARM::FLDMS;
- case ARM::FSTS:
- NumFSTMGened++;
- return ARM::FSTMS;
- case ARM::FLDD:
- NumFLDMGened++;
- return ARM::FLDMD;
- case ARM::FSTD:
- NumFSTMGened++;
- return ARM::FSTMD;
- default: abort();
+ case ARM::t2LDRi8:
+ case ARM::t2LDRi12:
+ ++NumLDMGened;
+ return ARM::t2LDM;
+ case ARM::t2STRi8:
+ case ARM::t2STRi12:
+ ++NumSTMGened;
+ return ARM::t2STM;
+ case ARM::VLDRS:
+ ++NumVLDMGened;
+ return ARM::VLDMS;
+ case ARM::VSTRS:
+ ++NumVSTMGened;
+ return ARM::VSTMS;
+ case ARM::VLDRD:
+ ++NumVLDMGened;
+ return ARM::VLDMD;
+ case ARM::VSTRD:
+ ++NumVSTMGened;
+ return ARM::VSTMD;
+ default: llvm_unreachable("Unhandled opcode!");
}
return 0;
}
-/// mergeOps - Create and insert a LDM or STM with Base as base register and
+static bool isT2i32Load(unsigned Opc) {
+ return Opc == ARM::t2LDRi12 || Opc == ARM::t2LDRi8;
+}
+
+static bool isi32Load(unsigned Opc) {
+ return Opc == ARM::LDR || isT2i32Load(Opc);
+}
+
+static bool isT2i32Store(unsigned Opc) {
+ return Opc == ARM::t2STRi12 || Opc == ARM::t2STRi8;
+}
+
+static bool isi32Store(unsigned Opc) {
+ return Opc == ARM::STR || isT2i32Store(Opc);
+}
+
+/// MergeOps - Create and insert a LDM or STM with Base as base register and
/// registers in Regs as the register operands that would be loaded / stored.
-/// It returns true if the transformation is done.
-static bool mergeOps(MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI,
- int Offset, unsigned Base, bool BaseKill, int Opcode,
- ARMCC::CondCodes Pred, unsigned PredReg, unsigned Scratch,
- SmallVector<std::pair<unsigned, bool>, 8> &Regs,
- const TargetInstrInfo *TII) {
+/// It returns true if the transformation is done.
+bool
+ARMLoadStoreOpt::MergeOps(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MBBI,
+ int Offset, unsigned Base, bool BaseKill,
+ int Opcode, ARMCC::CondCodes Pred,
+ unsigned PredReg, unsigned Scratch, DebugLoc dl,
+ SmallVector<std::pair<unsigned, bool>, 8> &Regs) {
// Only a single register to load / store. Don't bother.
unsigned NumRegs = Regs.size();
if (NumRegs <= 1)
return false;
ARM_AM::AMSubMode Mode = ARM_AM::ia;
- bool isAM4 = Opcode == ARM::LDR || Opcode == ARM::STR;
- if (isAM4 && Offset == 4)
+ bool isAM4 = isi32Load(Opcode) || isi32Store(Opcode);
+ if (isAM4 && Offset == 4) {
+ if (isThumb2)
+ // Thumb2 does not support ldmib / stmib.
+ return false;
Mode = ARM_AM::ib;
- else if (isAM4 && Offset == -4 * (int)NumRegs + 4)
+ } else if (isAM4 && Offset == -4 * (int)NumRegs + 4) {
+ if (isThumb2)
+ // Thumb2 does not support ldmda / stmda.
+ return false;
Mode = ARM_AM::da;
- else if (isAM4 && Offset == -4 * (int)NumRegs)
+ } else if (isAM4 && Offset == -4 * (int)NumRegs) {
Mode = ARM_AM::db;
- else if (Offset != 0) {
+ } else if (Offset != 0) {
// If starting offset isn't zero, insert a MI to materialize a new base.
// But only do so if it is cost effective, i.e. merging more than two
// loads / stores.
return false;
unsigned NewBase;
- if (Opcode == ARM::LDR)
+ if (isi32Load(Opcode))
// If it is a load, then just use one of the destination register to
// use as the new base.
NewBase = Regs[NumRegs-1].first;
if (NewBase == 0)
return false;
}
- int BaseOpc = ARM::ADDri;
+ int BaseOpc = !isThumb2
+ ? ARM::ADDri
+ : ((Base == ARM::SP) ? ARM::t2ADDrSPi : ARM::t2ADDri);
if (Offset < 0) {
- BaseOpc = ARM::SUBri;
+ BaseOpc = !isThumb2
+ ? ARM::SUBri
+ : ((Base == ARM::SP) ? ARM::t2SUBrSPi : ARM::t2SUBri);
Offset = - Offset;
}
- int ImmedOffset = ARM_AM::getSOImmVal(Offset);
+ int ImmedOffset = isThumb2
+ ? ARM_AM::getT2SOImmVal(Offset) : ARM_AM::getSOImmVal(Offset);
if (ImmedOffset == -1)
+ // FIXME: Try t2ADDri12 or t2SUBri12?
return false; // Probably not worth it then.
- BuildMI(MBB, MBBI, TII->get(BaseOpc), NewBase)
- .addReg(Base, false, false, BaseKill).addImm(ImmedOffset)
+ BuildMI(MBB, MBBI, dl, TII->get(BaseOpc), NewBase)
+ .addReg(Base, getKillRegState(BaseKill)).addImm(Offset)
.addImm(Pred).addReg(PredReg).addReg(0);
Base = NewBase;
BaseKill = true; // New base is always killed right its use.
}
- bool isDPR = Opcode == ARM::FLDD || Opcode == ARM::FSTD;
- bool isDef = Opcode == ARM::LDR || Opcode == ARM::FLDS || Opcode == ARM::FLDD;
+ bool isDPR = (Opcode == ARM::VLDRD || Opcode == ARM::VSTRD);
+ bool isDef = (isi32Load(Opcode) || Opcode == ARM::VLDRS ||
+ Opcode == ARM::VLDRD);
Opcode = getLoadStoreMultipleOpcode(Opcode);
MachineInstrBuilder MIB = (isAM4)
- ? BuildMI(MBB, MBBI, TII->get(Opcode)).addReg(Base, false, false, BaseKill)
+ ? BuildMI(MBB, MBBI, dl, TII->get(Opcode))
+ .addReg(Base, getKillRegState(BaseKill))
.addImm(ARM_AM::getAM4ModeImm(Mode)).addImm(Pred).addReg(PredReg)
- : BuildMI(MBB, MBBI, TII->get(Opcode)).addReg(Base, false, false, BaseKill)
- .addImm(ARM_AM::getAM5Opc(Mode, false, isDPR ? NumRegs<<1 : NumRegs))
+ : BuildMI(MBB, MBBI, dl, TII->get(Opcode))
+ .addReg(Base, getKillRegState(BaseKill))
+ .addImm(ARM_AM::getAM5Opc(Mode, isDPR ? NumRegs<<1 : NumRegs))
.addImm(Pred).addReg(PredReg);
for (unsigned i = 0; i != NumRegs; ++i)
- MIB = MIB.addReg(Regs[i].first, isDef, false, Regs[i].second);
+ MIB = MIB.addReg(Regs[i].first, getDefRegState(isDef)
+ | getKillRegState(Regs[i].second));
return true;
}
+// MergeOpsUpdate - call MergeOps and update MemOps and merges accordingly on
+// success.
+void ARMLoadStoreOpt::MergeOpsUpdate(MachineBasicBlock &MBB,
+ MemOpQueue &memOps,
+ unsigned memOpsBegin, unsigned memOpsEnd,
+ unsigned insertAfter, int Offset,
+ unsigned Base, bool BaseKill,
+ int Opcode,
+ ARMCC::CondCodes Pred, unsigned PredReg,
+ unsigned Scratch,
+ DebugLoc dl,
+ SmallVector<MachineBasicBlock::iterator, 4> &Merges) {
+ // First calculate which of the registers should be killed by the merged
+ // instruction.
+ const unsigned insertPos = memOps[insertAfter].Position;
+
+ SmallSet<unsigned, 4> UnavailRegs;
+ SmallSet<unsigned, 4> KilledRegs;
+ DenseMap<unsigned, unsigned> Killer;
+ for (unsigned i = 0; i < memOpsBegin; ++i) {
+ if (memOps[i].Position < insertPos && memOps[i].isKill) {
+ unsigned Reg = memOps[i].Reg;
+ if (memOps[i].Merged)
+ UnavailRegs.insert(Reg);
+ else {
+ KilledRegs.insert(Reg);
+ Killer[Reg] = i;
+ }
+ }
+ }
+ for (unsigned i = memOpsEnd, e = memOps.size(); i != e; ++i) {
+ if (memOps[i].Position < insertPos && memOps[i].isKill) {
+ unsigned Reg = memOps[i].Reg;
+ KilledRegs.insert(Reg);
+ Killer[Reg] = i;
+ }
+ }
+
+ SmallVector<std::pair<unsigned, bool>, 8> Regs;
+ for (unsigned i = memOpsBegin; i < memOpsEnd; ++i) {
+ unsigned Reg = memOps[i].Reg;
+ if (UnavailRegs.count(Reg))
+ // Register is killed before and it's not easy / possible to update the
+ // kill marker on already merged instructions. Abort.
+ return;
+
+ // If we are inserting the merged operation after an unmerged operation that
+ // uses the same register, make sure to transfer any kill flag.
+ bool isKill = memOps[i].isKill || KilledRegs.count(Reg);
+ Regs.push_back(std::make_pair(Reg, isKill));
+ }
+
+ // Try to do the merge.
+ MachineBasicBlock::iterator Loc = memOps[insertAfter].MBBI;
+ ++Loc;
+ if (!MergeOps(MBB, Loc, Offset, Base, BaseKill, Opcode,
+ Pred, PredReg, Scratch, dl, Regs))
+ return;
+
+ // Merge succeeded, update records.
+ Merges.push_back(prior(Loc));
+ for (unsigned i = memOpsBegin; i < memOpsEnd; ++i) {
+ // Remove kill flags from any unmerged memops that come before insertPos.
+ if (Regs[i-memOpsBegin].second) {
+ unsigned Reg = Regs[i-memOpsBegin].first;
+ if (KilledRegs.count(Reg)) {
+ unsigned j = Killer[Reg];
+ memOps[j].MBBI->getOperand(0).setIsKill(false);
+ }
+ }
+ MBB.erase(memOps[i].MBBI);
+ memOps[i].Merged = true;
+ }
+}
+
/// MergeLDR_STR - Merge a number of load / store instructions into one or more
/// load / store multiple instructions.
-SmallVector<MachineBasicBlock::iterator, 4>
+void
ARMLoadStoreOpt::MergeLDR_STR(MachineBasicBlock &MBB, unsigned SIndex,
- unsigned Base, int Opcode, unsigned Size,
- ARMCC::CondCodes Pred, unsigned PredReg,
- unsigned Scratch, MemOpQueue &MemOps) {
- SmallVector<MachineBasicBlock::iterator, 4> Merges;
- bool isAM4 = Opcode == ARM::LDR || Opcode == ARM::STR;
+ unsigned Base, int Opcode, unsigned Size,
+ ARMCC::CondCodes Pred, unsigned PredReg,
+ unsigned Scratch, MemOpQueue &MemOps,
+ SmallVector<MachineBasicBlock::iterator, 4> &Merges) {
+ bool isAM4 = isi32Load(Opcode) || isi32Store(Opcode);
int Offset = MemOps[SIndex].Offset;
int SOffset = Offset;
- unsigned Pos = MemOps[SIndex].Position;
+ unsigned insertAfter = SIndex;
MachineBasicBlock::iterator Loc = MemOps[SIndex].MBBI;
- unsigned PReg = MemOps[SIndex].MBBI->getOperand(0).getReg();
- unsigned PRegNum = ARMRegisterInfo::getRegisterNumbering(PReg);
- bool isKill = MemOps[SIndex].MBBI->getOperand(0).isKill();
+ DebugLoc dl = Loc->getDebugLoc();
+ const MachineOperand &PMO = Loc->getOperand(0);
+ unsigned PReg = PMO.getReg();
+ unsigned PRegNum = PMO.isUndef() ? UINT_MAX
+ : ARMRegisterInfo::getRegisterNumbering(PReg);
+ unsigned Count = 1;
- SmallVector<std::pair<unsigned,bool>, 8> Regs;
- Regs.push_back(std::make_pair(PReg, isKill));
for (unsigned i = SIndex+1, e = MemOps.size(); i != e; ++i) {
int NewOffset = MemOps[i].Offset;
- unsigned Reg = MemOps[i].MBBI->getOperand(0).getReg();
- unsigned RegNum = ARMRegisterInfo::getRegisterNumbering(Reg);
- isKill = MemOps[i].MBBI->getOperand(0).isKill();
+ const MachineOperand &MO = MemOps[i].MBBI->getOperand(0);
+ unsigned Reg = MO.getReg();
+ unsigned RegNum = MO.isUndef() ? UINT_MAX
+ : ARMRegisterInfo::getRegisterNumbering(Reg);
// AM4 - register numbers in ascending order.
// AM5 - consecutive register numbers in ascending order.
- if (NewOffset == Offset + (int)Size &&
- ((isAM4 && RegNum > PRegNum) || RegNum == PRegNum+1)) {
+ // Can only do up to 16 double-word registers per insn.
+ if (Reg != ARM::SP &&
+ NewOffset == Offset + (int)Size &&
+ ((isAM4 && RegNum > PRegNum)
+ || ((Size < 8 || Count < 16) && RegNum == PRegNum+1))) {
Offset += Size;
- Regs.push_back(std::make_pair(Reg, isKill));
PRegNum = RegNum;
+ ++Count;
} else {
// Can't merge this in. Try merge the earlier ones first.
- if (mergeOps(MBB, ++Loc, SOffset, Base, false, Opcode, Pred, PredReg,
- Scratch, Regs, TII)) {
- Merges.push_back(prior(Loc));
- for (unsigned j = SIndex; j < i; ++j) {
- MBB.erase(MemOps[j].MBBI);
- MemOps[j].Merged = true;
- }
- }
- SmallVector<MachineBasicBlock::iterator, 4> Merges2 =
- MergeLDR_STR(MBB, i, Base, Opcode, Size, Pred, PredReg, Scratch,MemOps);
- Merges.append(Merges2.begin(), Merges2.end());
- return Merges;
+ MergeOpsUpdate(MBB, MemOps, SIndex, i, insertAfter, SOffset,
+ Base, false, Opcode, Pred, PredReg, Scratch, dl, Merges);
+ MergeLDR_STR(MBB, i, Base, Opcode, Size, Pred, PredReg, Scratch,
+ MemOps, Merges);
+ return;
}
- if (MemOps[i].Position > Pos) {
- Pos = MemOps[i].Position;
- Loc = MemOps[i].MBBI;
- }
+ if (MemOps[i].Position > MemOps[insertAfter].Position)
+ insertAfter = i;
}
bool BaseKill = Loc->findRegisterUseOperandIdx(Base, true) != -1;
- if (mergeOps(MBB, ++Loc, SOffset, Base, BaseKill, Opcode, Pred, PredReg,
- Scratch, Regs, TII)) {
- Merges.push_back(prior(Loc));
- for (unsigned i = SIndex, e = MemOps.size(); i != e; ++i) {
- MBB.erase(MemOps[i].MBBI);
- MemOps[i].Merged = true;
- }
- }
-
- return Merges;
-}
-
-/// getInstrPredicate - If instruction is predicated, returns its predicate
-/// condition, otherwise returns AL. It also returns the condition code
-/// register by reference.
-static ARMCC::CondCodes getInstrPredicate(MachineInstr *MI, unsigned &PredReg) {
- int PIdx = MI->findFirstPredOperandIdx();
- if (PIdx == -1) {
- PredReg = 0;
- return ARMCC::AL;
- }
-
- PredReg = MI->getOperand(PIdx+1).getReg();
- return (ARMCC::CondCodes)MI->getOperand(PIdx).getImm();
+ MergeOpsUpdate(MBB, MemOps, SIndex, MemOps.size(), insertAfter, SOffset,
+ Base, BaseKill, Opcode, Pred, PredReg, Scratch, dl, Merges);
+ return;
}
static inline bool isMatchingDecrement(MachineInstr *MI, unsigned Base,
- unsigned Bytes, ARMCC::CondCodes Pred,
- unsigned PredReg) {
+ unsigned Bytes, unsigned Limit,
+ ARMCC::CondCodes Pred, unsigned PredReg){
unsigned MyPredReg = 0;
- return (MI && MI->getOpcode() == ARM::SUBri &&
- MI->getOperand(0).getReg() == Base &&
+ if (!MI)
+ return false;
+ if (MI->getOpcode() != ARM::t2SUBri &&
+ MI->getOpcode() != ARM::t2SUBrSPi &&
+ MI->getOpcode() != ARM::t2SUBrSPi12 &&
+ MI->getOpcode() != ARM::tSUBspi &&
+ MI->getOpcode() != ARM::SUBri)
+ return false;
+
+ // Make sure the offset fits in 8 bits.
+ if (Bytes <= 0 || (Limit && Bytes >= Limit))
+ return false;
+
+ unsigned Scale = (MI->getOpcode() == ARM::tSUBspi) ? 4 : 1; // FIXME
+ return (MI->getOperand(0).getReg() == Base &&
MI->getOperand(1).getReg() == Base &&
- ARM_AM::getAM2Offset(MI->getOperand(2).getImm()) == Bytes &&
- getInstrPredicate(MI, MyPredReg) == Pred &&
+ (MI->getOperand(2).getImm()*Scale) == Bytes &&
+ llvm::getInstrPredicate(MI, MyPredReg) == Pred &&
MyPredReg == PredReg);
}
static inline bool isMatchingIncrement(MachineInstr *MI, unsigned Base,
- unsigned Bytes, ARMCC::CondCodes Pred,
- unsigned PredReg) {
+ unsigned Bytes, unsigned Limit,
+ ARMCC::CondCodes Pred, unsigned PredReg){
unsigned MyPredReg = 0;
- return (MI && MI->getOpcode() == ARM::ADDri &&
- MI->getOperand(0).getReg() == Base &&
+ if (!MI)
+ return false;
+ if (MI->getOpcode() != ARM::t2ADDri &&
+ MI->getOpcode() != ARM::t2ADDrSPi &&
+ MI->getOpcode() != ARM::t2ADDrSPi12 &&
+ MI->getOpcode() != ARM::tADDspi &&
+ MI->getOpcode() != ARM::ADDri)
+ return false;
+
+ if (Bytes <= 0 || (Limit && Bytes >= Limit))
+ // Make sure the offset fits in 8 bits.
+ return false;
+
+ unsigned Scale = (MI->getOpcode() == ARM::tADDspi) ? 4 : 1; // FIXME
+ return (MI->getOperand(0).getReg() == Base &&
MI->getOperand(1).getReg() == Base &&
- ARM_AM::getAM2Offset(MI->getOperand(2).getImm()) == Bytes &&
- getInstrPredicate(MI, MyPredReg) == Pred &&
+ (MI->getOperand(2).getImm()*Scale) == Bytes &&
+ llvm::getInstrPredicate(MI, MyPredReg) == Pred &&
MyPredReg == PredReg);
}
default: return 0;
case ARM::LDR:
case ARM::STR:
- case ARM::FLDS:
- case ARM::FSTS:
+ case ARM::t2LDRi8:
+ case ARM::t2LDRi12:
+ case ARM::t2STRi8:
+ case ARM::t2STRi12:
+ case ARM::VLDRS:
+ case ARM::VSTRS:
return 4;
- case ARM::FLDD:
- case ARM::FSTD:
+ case ARM::VLDRD:
+ case ARM::VSTRD:
return 8;
case ARM::LDM:
case ARM::STM:
+ case ARM::t2LDM:
+ case ARM::t2STM:
return (MI->getNumOperands() - 4) * 4;
- case ARM::FLDMS:
- case ARM::FSTMS:
- case ARM::FLDMD:
- case ARM::FSTMD:
+ case ARM::VLDMS:
+ case ARM::VSTMS:
+ case ARM::VLDMD:
+ case ARM::VSTMD:
return ARM_AM::getAM5Offset(MI->getOperand(1).getImm()) * 4;
}
}
-/// mergeBaseUpdateLSMultiple - Fold proceeding/trailing inc/dec of base
-/// register into the LDM/STM/FLDM{D|S}/FSTM{D|S} op when possible:
+static unsigned getUpdatingLSMultipleOpcode(unsigned Opc) {
+ switch (Opc) {
+ case ARM::LDM: return ARM::LDM_UPD;
+ case ARM::STM: return ARM::STM_UPD;
+ case ARM::t2LDM: return ARM::t2LDM_UPD;
+ case ARM::t2STM: return ARM::t2STM_UPD;
+ case ARM::VLDMS: return ARM::VLDMS_UPD;
+ case ARM::VLDMD: return ARM::VLDMD_UPD;
+ case ARM::VSTMS: return ARM::VSTMS_UPD;
+ case ARM::VSTMD: return ARM::VSTMD_UPD;
+ default: llvm_unreachable("Unhandled opcode!");
+ }
+ return 0;
+}
+
+/// MergeBaseUpdateLSMultiple - Fold proceeding/trailing inc/dec of base
+/// register into the LDM/STM/VLDM{D|S}/VSTM{D|S} op when possible:
///
/// stmia rn, <ra, rb, rc>
/// rn := rn + 4 * 3;
/// ldmia rn, <ra, rb, rc>
/// =>
/// ldmdb rn!, <ra, rb, rc>
-static bool mergeBaseUpdateLSMultiple(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator MBBI,
- bool &Advance,
- MachineBasicBlock::iterator &I) {
+bool ARMLoadStoreOpt::MergeBaseUpdateLSMultiple(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MBBI,
+ bool &Advance,
+ MachineBasicBlock::iterator &I) {
MachineInstr *MI = MBBI;
unsigned Base = MI->getOperand(0).getReg();
+ bool BaseKill = MI->getOperand(0).isKill();
unsigned Bytes = getLSMultipleTransferSize(MI);
unsigned PredReg = 0;
- ARMCC::CondCodes Pred = getInstrPredicate(MI, PredReg);
+ ARMCC::CondCodes Pred = llvm::getInstrPredicate(MI, PredReg);
int Opcode = MI->getOpcode();
- bool isAM4 = Opcode == ARM::LDM || Opcode == ARM::STM;
+ DebugLoc dl = MI->getDebugLoc();
+ bool isAM4 = (Opcode == ARM::LDM || Opcode == ARM::t2LDM ||
+ Opcode == ARM::STM || Opcode == ARM::t2STM);
- if (isAM4) {
- if (ARM_AM::getAM4WBFlag(MI->getOperand(1).getImm()))
- return false;
+ bool DoMerge = false;
+ ARM_AM::AMSubMode Mode = ARM_AM::ia;
+ unsigned Offset = 0;
- // Can't use the updating AM4 sub-mode if the base register is also a dest
+ if (isAM4) {
+ // Can't use an updating ld/st if the base register is also a dest
// register. e.g. ldmdb r0!, {r0, r1, r2}. The behavior is undefined.
for (unsigned i = 3, e = MI->getNumOperands(); i != e; ++i) {
if (MI->getOperand(i).getReg() == Base)
return false;
}
+ Mode = ARM_AM::getAM4SubMode(MI->getOperand(1).getImm());
+ } else {
+ // VLDM{D|S}, VSTM{D|S} addressing mode 5 ops.
+ Mode = ARM_AM::getAM5SubMode(MI->getOperand(1).getImm());
+ Offset = ARM_AM::getAM5Offset(MI->getOperand(1).getImm());
+ }
- ARM_AM::AMSubMode Mode = ARM_AM::getAM4SubMode(MI->getOperand(1).getImm());
- if (MBBI != MBB.begin()) {
- MachineBasicBlock::iterator PrevMBBI = prior(MBBI);
+ // Try merging with the previous instruction.
+ MachineBasicBlock::iterator BeginMBBI = MBB.begin();
+ if (MBBI != BeginMBBI) {
+ MachineBasicBlock::iterator PrevMBBI = prior(MBBI);
+ while (PrevMBBI != BeginMBBI && PrevMBBI->isDebugValue())
+ --PrevMBBI;
+ if (isAM4) {
if (Mode == ARM_AM::ia &&
- isMatchingDecrement(PrevMBBI, Base, Bytes, Pred, PredReg)) {
- MI->getOperand(1).setImm(ARM_AM::getAM4ModeImm(ARM_AM::db, true));
- MBB.erase(PrevMBBI);
- return true;
- } else if (Mode == ARM_AM::ib &&
- isMatchingDecrement(PrevMBBI, Base, Bytes, Pred, PredReg)) {
- MI->getOperand(1).setImm(ARM_AM::getAM4ModeImm(ARM_AM::da, true));
- MBB.erase(PrevMBBI);
- return true;
+ isMatchingDecrement(PrevMBBI, Base, Bytes, 0, Pred, PredReg)) {
+ DoMerge = true;
+ Mode = ARM_AM::db;
+ } else if (isAM4 && Mode == ARM_AM::ib &&
+ isMatchingDecrement(PrevMBBI, Base, Bytes, 0, Pred, PredReg)) {
+ DoMerge = true;
+ Mode = ARM_AM::da;
+ }
+ } else {
+ if (Mode == ARM_AM::ia &&
+ isMatchingDecrement(PrevMBBI, Base, Bytes, 0, Pred, PredReg)) {
+ Mode = ARM_AM::db;
+ DoMerge = true;
}
}
+ if (DoMerge)
+ MBB.erase(PrevMBBI);
+ }
- if (MBBI != MBB.end()) {
- MachineBasicBlock::iterator NextMBBI = next(MBBI);
+ // Try merging with the next instruction.
+ MachineBasicBlock::iterator EndMBBI = MBB.end();
+ if (!DoMerge && MBBI != EndMBBI) {
+ MachineBasicBlock::iterator NextMBBI = llvm::next(MBBI);
+ while (NextMBBI != EndMBBI && NextMBBI->isDebugValue())
+ ++NextMBBI;
+ if (isAM4) {
if ((Mode == ARM_AM::ia || Mode == ARM_AM::ib) &&
- isMatchingIncrement(NextMBBI, Base, Bytes, Pred, PredReg)) {
- MI->getOperand(1).setImm(ARM_AM::getAM4ModeImm(Mode, true));
- if (NextMBBI == I) {
- Advance = true;
- ++I;
- }
- MBB.erase(NextMBBI);
- return true;
+ isMatchingIncrement(NextMBBI, Base, Bytes, 0, Pred, PredReg)) {
+ DoMerge = true;
} else if ((Mode == ARM_AM::da || Mode == ARM_AM::db) &&
- isMatchingDecrement(NextMBBI, Base, Bytes, Pred, PredReg)) {
- MI->getOperand(1).setImm(ARM_AM::getAM4ModeImm(Mode, true));
- if (NextMBBI == I) {
- Advance = true;
- ++I;
- }
- MBB.erase(NextMBBI);
- return true;
+ isMatchingDecrement(NextMBBI, Base, Bytes, 0, Pred, PredReg)) {
+ DoMerge = true;
}
- }
- } else {
- // FLDM{D|S}, FSTM{D|S} addressing mode 5 ops.
- if (ARM_AM::getAM5WBFlag(MI->getOperand(1).getImm()))
- return false;
-
- ARM_AM::AMSubMode Mode = ARM_AM::getAM5SubMode(MI->getOperand(1).getImm());
- unsigned Offset = ARM_AM::getAM5Offset(MI->getOperand(1).getImm());
- if (MBBI != MBB.begin()) {
- MachineBasicBlock::iterator PrevMBBI = prior(MBBI);
+ } else {
if (Mode == ARM_AM::ia &&
- isMatchingDecrement(PrevMBBI, Base, Bytes, Pred, PredReg)) {
- MI->getOperand(1).setImm(ARM_AM::getAM5Opc(ARM_AM::db, true, Offset));
- MBB.erase(PrevMBBI);
- return true;
+ isMatchingIncrement(NextMBBI, Base, Bytes, 0, Pred, PredReg)) {
+ DoMerge = true;
}
}
-
- if (MBBI != MBB.end()) {
- MachineBasicBlock::iterator NextMBBI = next(MBBI);
- if (Mode == ARM_AM::ia &&
- isMatchingIncrement(NextMBBI, Base, Bytes, Pred, PredReg)) {
- MI->getOperand(1).setImm(ARM_AM::getAM5Opc(ARM_AM::ia, true, Offset));
- if (NextMBBI == I) {
- Advance = true;
- ++I;
- }
- MBB.erase(NextMBBI);
+ if (DoMerge) {
+ if (NextMBBI == I) {
+ Advance = true;
+ ++I;
}
- return true;
+ MBB.erase(NextMBBI);
}
}
- return false;
+ if (!DoMerge)
+ return false;
+
+ unsigned NewOpc = getUpdatingLSMultipleOpcode(Opcode);
+ MachineInstrBuilder MIB = BuildMI(MBB, MBBI, dl, TII->get(NewOpc))
+ .addReg(Base, getDefRegState(true)) // WB base register
+ .addReg(Base, getKillRegState(BaseKill));
+ if (isAM4) {
+ // [t2]LDM_UPD, [t2]STM_UPD
+ MIB.addImm(ARM_AM::getAM4ModeImm(Mode))
+ .addImm(Pred).addReg(PredReg);
+ } else {
+ // VLDM[SD}_UPD, VSTM[SD]_UPD
+ MIB.addImm(ARM_AM::getAM5Opc(Mode, Offset))
+ .addImm(Pred).addReg(PredReg);
+ }
+ // Transfer the rest of operands.
+ for (unsigned OpNum = 4, e = MI->getNumOperands(); OpNum != e; ++OpNum)
+ MIB.addOperand(MI->getOperand(OpNum));
+ // Transfer memoperands.
+ (*MIB).setMemRefs(MI->memoperands_begin(), MI->memoperands_end());
+
+ MBB.erase(MBBI);
+ return true;
}
static unsigned getPreIndexedLoadStoreOpcode(unsigned Opc) {
switch (Opc) {
case ARM::LDR: return ARM::LDR_PRE;
case ARM::STR: return ARM::STR_PRE;
- case ARM::FLDS: return ARM::FLDMS;
- case ARM::FLDD: return ARM::FLDMD;
- case ARM::FSTS: return ARM::FSTMS;
- case ARM::FSTD: return ARM::FSTMD;
- default: abort();
+ case ARM::VLDRS: return ARM::VLDMS_UPD;
+ case ARM::VLDRD: return ARM::VLDMD_UPD;
+ case ARM::VSTRS: return ARM::VSTMS_UPD;
+ case ARM::VSTRD: return ARM::VSTMD_UPD;
+ case ARM::t2LDRi8:
+ case ARM::t2LDRi12:
+ return ARM::t2LDR_PRE;
+ case ARM::t2STRi8:
+ case ARM::t2STRi12:
+ return ARM::t2STR_PRE;
+ default: llvm_unreachable("Unhandled opcode!");
}
return 0;
}
switch (Opc) {
case ARM::LDR: return ARM::LDR_POST;
case ARM::STR: return ARM::STR_POST;
- case ARM::FLDS: return ARM::FLDMS;
- case ARM::FLDD: return ARM::FLDMD;
- case ARM::FSTS: return ARM::FSTMS;
- case ARM::FSTD: return ARM::FSTMD;
- default: abort();
+ case ARM::VLDRS: return ARM::VLDMS_UPD;
+ case ARM::VLDRD: return ARM::VLDMD_UPD;
+ case ARM::VSTRS: return ARM::VSTMS_UPD;
+ case ARM::VSTRD: return ARM::VSTMD_UPD;
+ case ARM::t2LDRi8:
+ case ARM::t2LDRi12:
+ return ARM::t2LDR_POST;
+ case ARM::t2STRi8:
+ case ARM::t2STRi12:
+ return ARM::t2STR_POST;
+ default: llvm_unreachable("Unhandled opcode!");
}
return 0;
}
-/// mergeBaseUpdateLoadStore - Fold proceeding/trailing inc/dec of base
+/// MergeBaseUpdateLoadStore - Fold proceeding/trailing inc/dec of base
/// register into the LDR/STR/FLD{D|S}/FST{D|S} op when possible:
-static bool mergeBaseUpdateLoadStore(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator MBBI,
- const TargetInstrInfo *TII,
- bool &Advance,
- MachineBasicBlock::iterator &I) {
+bool ARMLoadStoreOpt::MergeBaseUpdateLoadStore(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MBBI,
+ const TargetInstrInfo *TII,
+ bool &Advance,
+ MachineBasicBlock::iterator &I) {
MachineInstr *MI = MBBI;
unsigned Base = MI->getOperand(1).getReg();
bool BaseKill = MI->getOperand(1).isKill();
unsigned Bytes = getLSMultipleTransferSize(MI);
int Opcode = MI->getOpcode();
- bool isAM2 = Opcode == ARM::LDR || Opcode == ARM::STR;
- if ((isAM2 && ARM_AM::getAM2Offset(MI->getOperand(3).getImm()) != 0) ||
- (!isAM2 && ARM_AM::getAM5Offset(MI->getOperand(2).getImm()) != 0))
+ DebugLoc dl = MI->getDebugLoc();
+ bool isAM5 = (Opcode == ARM::VLDRD || Opcode == ARM::VLDRS ||
+ Opcode == ARM::VSTRD || Opcode == ARM::VSTRS);
+ bool isAM2 = (Opcode == ARM::LDR || Opcode == ARM::STR);
+ if (isAM2 && ARM_AM::getAM2Offset(MI->getOperand(3).getImm()) != 0)
return false;
+ if (isAM5 && ARM_AM::getAM5Offset(MI->getOperand(2).getImm()) != 0)
+ return false;
+ if (isT2i32Load(Opcode) || isT2i32Store(Opcode))
+ if (MI->getOperand(2).getImm() != 0)
+ return false;
- bool isLd = Opcode == ARM::LDR || Opcode == ARM::FLDS || Opcode == ARM::FLDD;
+ bool isLd = isi32Load(Opcode) || Opcode == ARM::VLDRS || Opcode == ARM::VLDRD;
// Can't do the merge if the destination register is the same as the would-be
// writeback register.
if (isLd && MI->getOperand(0).getReg() == Base)
return false;
unsigned PredReg = 0;
- ARMCC::CondCodes Pred = getInstrPredicate(MI, PredReg);
+ ARMCC::CondCodes Pred = llvm::getInstrPredicate(MI, PredReg);
bool DoMerge = false;
ARM_AM::AddrOpc AddSub = ARM_AM::add;
unsigned NewOpc = 0;
- if (MBBI != MBB.begin()) {
+ // AM2 - 12 bits, thumb2 - 8 bits.
+ unsigned Limit = isAM5 ? 0 : (isAM2 ? 0x1000 : 0x100);
+
+ // Try merging with the previous instruction.
+ MachineBasicBlock::iterator BeginMBBI = MBB.begin();
+ if (MBBI != BeginMBBI) {
MachineBasicBlock::iterator PrevMBBI = prior(MBBI);
- if (isMatchingDecrement(PrevMBBI, Base, Bytes, Pred, PredReg)) {
+ while (PrevMBBI != BeginMBBI && PrevMBBI->isDebugValue())
+ --PrevMBBI;
+ if (isMatchingDecrement(PrevMBBI, Base, Bytes, Limit, Pred, PredReg)) {
DoMerge = true;
AddSub = ARM_AM::sub;
- NewOpc = getPreIndexedLoadStoreOpcode(Opcode);
- } else if (isAM2 && isMatchingIncrement(PrevMBBI, Base, Bytes,
- Pred, PredReg)) {
+ } else if (!isAM5 &&
+ isMatchingIncrement(PrevMBBI, Base, Bytes, Limit,Pred,PredReg)) {
DoMerge = true;
- NewOpc = getPreIndexedLoadStoreOpcode(Opcode);
}
- if (DoMerge)
+ if (DoMerge) {
+ NewOpc = getPreIndexedLoadStoreOpcode(Opcode);
MBB.erase(PrevMBBI);
+ }
}
- if (!DoMerge && MBBI != MBB.end()) {
- MachineBasicBlock::iterator NextMBBI = next(MBBI);
- if (isAM2 && isMatchingDecrement(NextMBBI, Base, Bytes, Pred, PredReg)) {
+ // Try merging with the next instruction.
+ MachineBasicBlock::iterator EndMBBI = MBB.end();
+ if (!DoMerge && MBBI != EndMBBI) {
+ MachineBasicBlock::iterator NextMBBI = llvm::next(MBBI);
+ while (NextMBBI != EndMBBI && NextMBBI->isDebugValue())
+ ++NextMBBI;
+ if (!isAM5 &&
+ isMatchingDecrement(NextMBBI, Base, Bytes, Limit, Pred, PredReg)) {
DoMerge = true;
AddSub = ARM_AM::sub;
- NewOpc = getPostIndexedLoadStoreOpcode(Opcode);
- } else if (isMatchingIncrement(NextMBBI, Base, Bytes, Pred, PredReg)) {
+ } else if (isMatchingIncrement(NextMBBI, Base, Bytes, Limit,Pred,PredReg)) {
DoMerge = true;
- NewOpc = getPostIndexedLoadStoreOpcode(Opcode);
}
if (DoMerge) {
+ NewOpc = getPostIndexedLoadStoreOpcode(Opcode);
if (NextMBBI == I) {
Advance = true;
++I;
if (!DoMerge)
return false;
- bool isDPR = NewOpc == ARM::FLDMD || NewOpc == ARM::FSTMD;
- unsigned Offset = isAM2 ? ARM_AM::getAM2Opc(AddSub, Bytes, ARM_AM::no_shift)
- : ARM_AM::getAM5Opc((AddSub == ARM_AM::sub) ? ARM_AM::db : ARM_AM::ia,
- true, isDPR ? 2 : 1);
- if (isLd) {
+ bool isDPR = NewOpc == ARM::VLDMD || NewOpc == ARM::VSTMD;
+ unsigned Offset = 0;
+ if (isAM5)
+ Offset = ARM_AM::getAM5Opc(AddSub == ARM_AM::sub ? ARM_AM::db : ARM_AM::ia,
+ (isDPR ? 2 : 1));
+ else if (isAM2)
+ Offset = ARM_AM::getAM2Opc(AddSub, Bytes, ARM_AM::no_shift);
+ else
+ Offset = AddSub == ARM_AM::sub ? -Bytes : Bytes;
+
+ if (isAM5) {
+ // VLDM[SD}_UPD, VSTM[SD]_UPD
+ MachineOperand &MO = MI->getOperand(0);
+ BuildMI(MBB, MBBI, dl, TII->get(NewOpc))
+ .addReg(Base, getDefRegState(true)) // WB base register
+ .addReg(Base, getKillRegState(isLd ? BaseKill : false))
+ .addImm(Offset)
+ .addImm(Pred).addReg(PredReg)
+ .addReg(MO.getReg(), (isLd ? getDefRegState(true) :
+ getKillRegState(MO.isKill())));
+ } else if (isLd) {
if (isAM2)
- // LDR_PRE, LDR_POST;
- BuildMI(MBB, MBBI, TII->get(NewOpc), MI->getOperand(0).getReg())
- .addReg(Base, true)
+ // LDR_PRE, LDR_POST,
+ BuildMI(MBB, MBBI, dl, TII->get(NewOpc), MI->getOperand(0).getReg())
+ .addReg(Base, RegState::Define)
.addReg(Base).addReg(0).addImm(Offset).addImm(Pred).addReg(PredReg);
else
- // FLDMS, FLDMD
- BuildMI(MBB, MBBI, TII->get(NewOpc)).addReg(Base, false, false, BaseKill)
- .addImm(Offset).addImm(Pred).addReg(PredReg)
- .addReg(MI->getOperand(0).getReg(), true);
+ // t2LDR_PRE, t2LDR_POST
+ BuildMI(MBB, MBBI, dl, TII->get(NewOpc), MI->getOperand(0).getReg())
+ .addReg(Base, RegState::Define)
+ .addReg(Base).addImm(Offset).addImm(Pred).addReg(PredReg);
} else {
MachineOperand &MO = MI->getOperand(0);
if (isAM2)
- // STR_PRE, STR_POST;
- BuildMI(MBB, MBBI, TII->get(NewOpc), Base)
- .addReg(MO.getReg(), false, false, MO.isKill())
+ // STR_PRE, STR_POST
+ BuildMI(MBB, MBBI, dl, TII->get(NewOpc), Base)
+ .addReg(MO.getReg(), getKillRegState(MO.isKill()))
.addReg(Base).addReg(0).addImm(Offset).addImm(Pred).addReg(PredReg);
else
- // FSTMS, FSTMD
- BuildMI(MBB, MBBI, TII->get(NewOpc)).addReg(Base).addImm(Offset)
- .addImm(Pred).addReg(PredReg)
- .addReg(MO.getReg(), false, false, MO.isKill());
+ // t2STR_PRE, t2STR_POST
+ BuildMI(MBB, MBBI, dl, TII->get(NewOpc), Base)
+ .addReg(MO.getReg(), getKillRegState(MO.isKill()))
+ .addReg(Base).addImm(Offset).addImm(Pred).addReg(PredReg);
}
MBB.erase(MBBI);
/// isMemoryOp - Returns true if instruction is a memory operations (that this
/// pass is capable of operating on).
-static bool isMemoryOp(MachineInstr *MI) {
+static bool isMemoryOp(const MachineInstr *MI) {
+ // When no memory operands are present, conservatively assume unaligned,
+ // volatile, unfoldable.
+ if (!MI->hasOneMemOperand())
+ return false;
+
+ const MachineMemOperand *MMO = *MI->memoperands_begin();
+
+ // Don't touch volatile memory accesses - we may be changing their order.
+ if (MMO->isVolatile())
+ return false;
+
+ // Unaligned ldr/str is emulated by some kernels, but unaligned ldm/stm is
+ // not.
+ if (MMO->getAlignment() < 4)
+ return false;
+
+ // str <undef> could probably be eliminated entirely, but for now we just want
+ // to avoid making a mess of it.
+ // FIXME: Use str <undef> as a wildcard to enable better stm folding.
+ if (MI->getNumOperands() > 0 && MI->getOperand(0).isReg() &&
+ MI->getOperand(0).isUndef())
+ return false;
+
+ // Likewise don't mess with references to undefined addresses.
+ if (MI->getNumOperands() > 1 && MI->getOperand(1).isReg() &&
+ MI->getOperand(1).isUndef())
+ return false;
+
int Opcode = MI->getOpcode();
switch (Opcode) {
default: break;
case ARM::LDR:
case ARM::STR:
return MI->getOperand(1).isReg() && MI->getOperand(2).getReg() == 0;
- case ARM::FLDS:
- case ARM::FSTS:
+ case ARM::VLDRS:
+ case ARM::VSTRS:
+ return MI->getOperand(1).isReg();
+ case ARM::VLDRD:
+ case ARM::VSTRD:
return MI->getOperand(1).isReg();
- case ARM::FLDD:
- case ARM::FSTD:
+ case ARM::t2LDRi8:
+ case ARM::t2LDRi12:
+ case ARM::t2STRi8:
+ case ARM::t2STRi12:
return MI->getOperand(1).isReg();
}
return false;
RS->forward(prior(Loc));
}
+static int getMemoryOpOffset(const MachineInstr *MI) {
+ int Opcode = MI->getOpcode();
+ bool isAM2 = Opcode == ARM::LDR || Opcode == ARM::STR;
+ bool isAM3 = Opcode == ARM::LDRD || Opcode == ARM::STRD;
+ unsigned NumOperands = MI->getDesc().getNumOperands();
+ unsigned OffField = MI->getOperand(NumOperands-3).getImm();
+
+ if (Opcode == ARM::t2LDRi12 || Opcode == ARM::t2LDRi8 ||
+ Opcode == ARM::t2STRi12 || Opcode == ARM::t2STRi8 ||
+ Opcode == ARM::t2LDRDi8 || Opcode == ARM::t2STRDi8)
+ return OffField;
+
+ int Offset = isAM2
+ ? ARM_AM::getAM2Offset(OffField)
+ : (isAM3 ? ARM_AM::getAM3Offset(OffField)
+ : ARM_AM::getAM5Offset(OffField) * 4);
+ if (isAM2) {
+ if (ARM_AM::getAM2Op(OffField) == ARM_AM::sub)
+ Offset = -Offset;
+ } else if (isAM3) {
+ if (ARM_AM::getAM3Op(OffField) == ARM_AM::sub)
+ Offset = -Offset;
+ } else {
+ if (ARM_AM::getAM5Op(OffField) == ARM_AM::sub)
+ Offset = -Offset;
+ }
+ return Offset;
+}
+
+static void InsertLDR_STR(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &MBBI,
+ int OffImm, bool isDef,
+ DebugLoc dl, unsigned NewOpc,
+ unsigned Reg, bool RegDeadKill, bool RegUndef,
+ unsigned BaseReg, bool BaseKill, bool BaseUndef,
+ unsigned OffReg, bool OffKill, bool OffUndef,
+ ARMCC::CondCodes Pred, unsigned PredReg,
+ const TargetInstrInfo *TII, bool isT2) {
+ int Offset = OffImm;
+ if (!isT2) {
+ if (OffImm < 0)
+ Offset = ARM_AM::getAM2Opc(ARM_AM::sub, -OffImm, ARM_AM::no_shift);
+ else
+ Offset = ARM_AM::getAM2Opc(ARM_AM::add, OffImm, ARM_AM::no_shift);
+ }
+ if (isDef) {
+ MachineInstrBuilder MIB = BuildMI(MBB, MBBI, MBBI->getDebugLoc(),
+ TII->get(NewOpc))
+ .addReg(Reg, getDefRegState(true) | getDeadRegState(RegDeadKill))
+ .addReg(BaseReg, getKillRegState(BaseKill)|getUndefRegState(BaseUndef));
+ if (!isT2)
+ MIB.addReg(OffReg, getKillRegState(OffKill)|getUndefRegState(OffUndef));
+ MIB.addImm(Offset).addImm(Pred).addReg(PredReg);
+ } else {
+ MachineInstrBuilder MIB = BuildMI(MBB, MBBI, MBBI->getDebugLoc(),
+ TII->get(NewOpc))
+ .addReg(Reg, getKillRegState(RegDeadKill) | getUndefRegState(RegUndef))
+ .addReg(BaseReg, getKillRegState(BaseKill)|getUndefRegState(BaseUndef));
+ if (!isT2)
+ MIB.addReg(OffReg, getKillRegState(OffKill)|getUndefRegState(OffUndef));
+ MIB.addImm(Offset).addImm(Pred).addReg(PredReg);
+ }
+}
+
+bool ARMLoadStoreOpt::FixInvalidRegPairOp(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &MBBI) {
+ MachineInstr *MI = &*MBBI;
+ unsigned Opcode = MI->getOpcode();
+ if (Opcode == ARM::LDRD || Opcode == ARM::STRD ||
+ Opcode == ARM::t2LDRDi8 || Opcode == ARM::t2STRDi8) {
+ unsigned EvenReg = MI->getOperand(0).getReg();
+ unsigned OddReg = MI->getOperand(1).getReg();
+ unsigned EvenRegNum = TRI->getDwarfRegNum(EvenReg, false);
+ unsigned OddRegNum = TRI->getDwarfRegNum(OddReg, false);
+ if ((EvenRegNum & 1) == 0 && (EvenRegNum + 1) == OddRegNum)
+ return false;
+
+ MachineBasicBlock::iterator NewBBI = MBBI;
+ bool isT2 = Opcode == ARM::t2LDRDi8 || Opcode == ARM::t2STRDi8;
+ bool isLd = Opcode == ARM::LDRD || Opcode == ARM::t2LDRDi8;
+ bool EvenDeadKill = isLd ?
+ MI->getOperand(0).isDead() : MI->getOperand(0).isKill();
+ bool EvenUndef = MI->getOperand(0).isUndef();
+ bool OddDeadKill = isLd ?
+ MI->getOperand(1).isDead() : MI->getOperand(1).isKill();
+ bool OddUndef = MI->getOperand(1).isUndef();
+ const MachineOperand &BaseOp = MI->getOperand(2);
+ unsigned BaseReg = BaseOp.getReg();
+ bool BaseKill = BaseOp.isKill();
+ bool BaseUndef = BaseOp.isUndef();
+ unsigned OffReg = isT2 ? 0 : MI->getOperand(3).getReg();
+ bool OffKill = isT2 ? false : MI->getOperand(3).isKill();
+ bool OffUndef = isT2 ? false : MI->getOperand(3).isUndef();
+ int OffImm = getMemoryOpOffset(MI);
+ unsigned PredReg = 0;
+ ARMCC::CondCodes Pred = llvm::getInstrPredicate(MI, PredReg);
+
+ if (OddRegNum > EvenRegNum && OffReg == 0 && OffImm == 0) {
+ // Ascending register numbers and no offset. It's safe to change it to a
+ // ldm or stm.
+ unsigned NewOpc = (isLd)
+ ? (isT2 ? ARM::t2LDM : ARM::LDM)
+ : (isT2 ? ARM::t2STM : ARM::STM);
+ if (isLd) {
+ BuildMI(MBB, MBBI, MBBI->getDebugLoc(), TII->get(NewOpc))
+ .addReg(BaseReg, getKillRegState(BaseKill))
+ .addImm(ARM_AM::getAM4ModeImm(ARM_AM::ia))
+ .addImm(Pred).addReg(PredReg)
+ .addReg(EvenReg, getDefRegState(isLd) | getDeadRegState(EvenDeadKill))
+ .addReg(OddReg, getDefRegState(isLd) | getDeadRegState(OddDeadKill));
+ ++NumLDRD2LDM;
+ } else {
+ BuildMI(MBB, MBBI, MBBI->getDebugLoc(), TII->get(NewOpc))
+ .addReg(BaseReg, getKillRegState(BaseKill))
+ .addImm(ARM_AM::getAM4ModeImm(ARM_AM::ia))
+ .addImm(Pred).addReg(PredReg)
+ .addReg(EvenReg,
+ getKillRegState(EvenDeadKill) | getUndefRegState(EvenUndef))
+ .addReg(OddReg,
+ getKillRegState(OddDeadKill) | getUndefRegState(OddUndef));
+ ++NumSTRD2STM;
+ }
+ NewBBI = llvm::prior(MBBI);
+ } else {
+ // Split into two instructions.
+ assert((!isT2 || !OffReg) &&
+ "Thumb2 ldrd / strd does not encode offset register!");
+ unsigned NewOpc = (isLd)
+ ? (isT2 ? (OffImm < 0 ? ARM::t2LDRi8 : ARM::t2LDRi12) : ARM::LDR)
+ : (isT2 ? (OffImm < 0 ? ARM::t2STRi8 : ARM::t2STRi12) : ARM::STR);
+ DebugLoc dl = MBBI->getDebugLoc();
+ // If this is a load and base register is killed, it may have been
+ // re-defed by the load, make sure the first load does not clobber it.
+ if (isLd &&
+ (BaseKill || OffKill) &&
+ (TRI->regsOverlap(EvenReg, BaseReg) ||
+ (OffReg && TRI->regsOverlap(EvenReg, OffReg)))) {
+ assert(!TRI->regsOverlap(OddReg, BaseReg) &&
+ (!OffReg || !TRI->regsOverlap(OddReg, OffReg)));
+ InsertLDR_STR(MBB, MBBI, OffImm+4, isLd, dl, NewOpc,
+ OddReg, OddDeadKill, false,
+ BaseReg, false, BaseUndef, OffReg, false, OffUndef,
+ Pred, PredReg, TII, isT2);
+ NewBBI = llvm::prior(MBBI);
+ InsertLDR_STR(MBB, MBBI, OffImm, isLd, dl, NewOpc,
+ EvenReg, EvenDeadKill, false,
+ BaseReg, BaseKill, BaseUndef, OffReg, OffKill, OffUndef,
+ Pred, PredReg, TII, isT2);
+ } else {
+ if (OddReg == EvenReg && EvenDeadKill) {
+ // If the two source operands are the same, the kill marker is
+ // probably on the first one. e.g.
+ // t2STRDi8 %R5<kill>, %R5, %R9<kill>, 0, 14, %reg0
+ EvenDeadKill = false;
+ OddDeadKill = true;
+ }
+ InsertLDR_STR(MBB, MBBI, OffImm, isLd, dl, NewOpc,
+ EvenReg, EvenDeadKill, EvenUndef,
+ BaseReg, false, BaseUndef, OffReg, false, OffUndef,
+ Pred, PredReg, TII, isT2);
+ NewBBI = llvm::prior(MBBI);
+ InsertLDR_STR(MBB, MBBI, OffImm+4, isLd, dl, NewOpc,
+ OddReg, OddDeadKill, OddUndef,
+ BaseReg, BaseKill, BaseUndef, OffReg, OffKill, OffUndef,
+ Pred, PredReg, TII, isT2);
+ }
+ if (isLd)
+ ++NumLDRD2LDR;
+ else
+ ++NumSTRD2STR;
+ }
+
+ MBB.erase(MI);
+ MBBI = NewBBI;
+ return true;
+ }
+ return false;
+}
+
/// LoadStoreMultipleOpti - An optimization pass to turn multiple LDR / STR
/// ops of the same base and incrementing offset into LDM / STM ops.
bool ARMLoadStoreOpt::LoadStoreMultipleOpti(MachineBasicBlock &MBB) {
ARMCC::CondCodes CurrPred = ARMCC::AL;
unsigned CurrPredReg = 0;
unsigned Position = 0;
+ SmallVector<MachineBasicBlock::iterator,4> Merges;
RS->enterBasicBlock(&MBB);
MachineBasicBlock::iterator MBBI = MBB.begin(), E = MBB.end();
while (MBBI != E) {
+ if (FixInvalidRegPairOp(MBB, MBBI))
+ continue;
+
bool Advance = false;
bool TryMerge = false;
bool Clobber = false;
bool isMemOp = isMemoryOp(MBBI);
if (isMemOp) {
int Opcode = MBBI->getOpcode();
- bool isAM2 = Opcode == ARM::LDR || Opcode == ARM::STR;
unsigned Size = getLSMultipleTransferSize(MBBI);
+ const MachineOperand &MO = MBBI->getOperand(0);
+ unsigned Reg = MO.getReg();
+ bool isKill = MO.isDef() ? false : MO.isKill();
unsigned Base = MBBI->getOperand(1).getReg();
unsigned PredReg = 0;
- ARMCC::CondCodes Pred = getInstrPredicate(MBBI, PredReg);
- unsigned NumOperands = MBBI->getDesc().getNumOperands();
- unsigned OffField = MBBI->getOperand(NumOperands-3).getImm();
- int Offset = isAM2
- ? ARM_AM::getAM2Offset(OffField) : ARM_AM::getAM5Offset(OffField) * 4;
- if (isAM2) {
- if (ARM_AM::getAM2Op(OffField) == ARM_AM::sub)
- Offset = -Offset;
- } else {
- if (ARM_AM::getAM5Op(OffField) == ARM_AM::sub)
- Offset = -Offset;
- }
+ ARMCC::CondCodes Pred = llvm::getInstrPredicate(MBBI, PredReg);
+ int Offset = getMemoryOpOffset(MBBI);
// Watch out for:
// r4 := ldr [r5]
// r5 := ldr [r5, #4]
// looks like the later ldr(s) use the same base register. Try to
// merge the ldr's so far, including this one. But don't try to
// combine the following ldr(s).
- Clobber = (Opcode == ARM::LDR && Base == MBBI->getOperand(0).getReg());
+ Clobber = (isi32Load(Opcode) && Base == MBBI->getOperand(0).getReg());
if (CurrBase == 0 && !Clobber) {
// Start of a new chain.
CurrBase = Base;
CurrSize = Size;
CurrPred = Pred;
CurrPredReg = PredReg;
- MemOps.push_back(MemOpQueueEntry(Offset, Position, MBBI));
- NumMemOps++;
+ MemOps.push_back(MemOpQueueEntry(Offset, Reg, isKill, Position, MBBI));
+ ++NumMemOps;
Advance = true;
} else {
if (Clobber) {
// No need to match PredReg.
// Continue adding to the queue.
if (Offset > MemOps.back().Offset) {
- MemOps.push_back(MemOpQueueEntry(Offset, Position, MBBI));
- NumMemOps++;
+ MemOps.push_back(MemOpQueueEntry(Offset, Reg, isKill,
+ Position, MBBI));
+ ++NumMemOps;
Advance = true;
} else {
for (MemOpQueueIter I = MemOps.begin(), E = MemOps.end();
I != E; ++I) {
if (Offset < I->Offset) {
- MemOps.insert(I, MemOpQueueEntry(Offset, Position, MBBI));
- NumMemOps++;
+ MemOps.insert(I, MemOpQueueEntry(Offset, Reg, isKill,
+ Position, MBBI));
+ ++NumMemOps;
Advance = true;
break;
} else if (Offset == I->Offset) {
}
}
- if (Advance) {
+ if (MBBI->isDebugValue()) {
+ ++MBBI;
+ if (MBBI == E)
+ // Reach the end of the block, try merging the memory instructions.
+ TryMerge = true;
+ } else if (Advance) {
++Position;
++MBBI;
+ if (MBBI == E)
+ // Reach the end of the block, try merging the memory instructions.
+ TryMerge = true;
} else
TryMerge = true;
// Try to find a free register to use as a new base in case it's needed.
// First advance to the instruction just before the start of the chain.
AdvanceRS(MBB, MemOps);
- // Find a scratch register. Make sure it's a call clobbered register or
- // a spilled callee-saved register.
- unsigned Scratch = RS->FindUnusedReg(&ARM::GPRRegClass, true);
- if (!Scratch)
- Scratch = RS->FindUnusedReg(&ARM::GPRRegClass,
- AFI->getSpilledCSRegisters());
+ // Find a scratch register.
+ unsigned Scratch = RS->FindUnusedReg(ARM::GPRRegisterClass);
// Process the load / store instructions.
RS->forward(prior(MBBI));
// Merge ops.
- SmallVector<MachineBasicBlock::iterator,4> MBBII =
- MergeLDR_STR(MBB, 0, CurrBase, CurrOpc, CurrSize,
- CurrPred, CurrPredReg, Scratch, MemOps);
+ Merges.clear();
+ MergeLDR_STR(MBB, 0, CurrBase, CurrOpc, CurrSize,
+ CurrPred, CurrPredReg, Scratch, MemOps, Merges);
// Try folding preceeding/trailing base inc/dec into the generated
// LDM/STM ops.
- for (unsigned i = 0, e = MBBII.size(); i < e; ++i)
- if (mergeBaseUpdateLSMultiple(MBB, MBBII[i], Advance, MBBI))
- NumMerges++;
- NumMerges += MBBII.size();
+ for (unsigned i = 0, e = Merges.size(); i < e; ++i)
+ if (MergeBaseUpdateLSMultiple(MBB, Merges[i], Advance, MBBI))
+ ++NumMerges;
+ NumMerges += Merges.size();
// Try folding preceeding/trailing base inc/dec into those load/store
// that were not merged to form LDM/STM ops.
for (unsigned i = 0; i != NumMemOps; ++i)
if (!MemOps[i].Merged)
- if (mergeBaseUpdateLoadStore(MBB, MemOps[i].MBBI, TII,Advance,MBBI))
- NumMerges++;
+ if (MergeBaseUpdateLoadStore(MBB, MemOps[i].MBBI, TII,Advance,MBBI))
+ ++NumMerges;
- // RS may be pointing to an instruction that's deleted.
+ // RS may be pointing to an instruction that's deleted.
RS->skipTo(prior(MBBI));
+ } else if (NumMemOps == 1) {
+ // Try folding preceeding/trailing base inc/dec into the single
+ // load/store.
+ if (MergeBaseUpdateLoadStore(MBB, MemOps[0].MBBI, TII, Advance, MBBI)) {
+ ++NumMerges;
+ RS->forward(prior(MBBI));
+ }
}
CurrBase = 0;
return NumMerges > 0;
}
-/// MergeReturnIntoLDM - If this is a exit BB, try merging the return op
-/// (bx lr) into the preceeding stack restore so it directly restore the value
-/// of LR into pc.
-/// ldmfd sp!, {r7, lr}
+namespace {
+ struct OffsetCompare {
+ bool operator()(const MachineInstr *LHS, const MachineInstr *RHS) const {
+ int LOffset = getMemoryOpOffset(LHS);
+ int ROffset = getMemoryOpOffset(RHS);
+ assert(LHS == RHS || LOffset != ROffset);
+ return LOffset > ROffset;
+ }
+ };
+}
+
+/// MergeReturnIntoLDM - If this is a exit BB, try merging the return ops
+/// ("bx lr" and "mov pc, lr") into the preceeding stack restore so it
+/// directly restore the value of LR into pc.
+/// ldmfd sp!, {..., lr}
/// bx lr
+/// or
+/// ldmfd sp!, {..., lr}
+/// mov pc, lr
/// =>
-/// ldmfd sp!, {r7, pc}
+/// ldmfd sp!, {..., pc}
bool ARMLoadStoreOpt::MergeReturnIntoLDM(MachineBasicBlock &MBB) {
if (MBB.empty()) return false;
MachineBasicBlock::iterator MBBI = prior(MBB.end());
- if (MBBI->getOpcode() == ARM::BX_RET && MBBI != MBB.begin()) {
+ if (MBBI != MBB.begin() &&
+ (MBBI->getOpcode() == ARM::BX_RET ||
+ MBBI->getOpcode() == ARM::tBX_RET ||
+ MBBI->getOpcode() == ARM::MOVPCLR)) {
MachineInstr *PrevMI = prior(MBBI);
- if (PrevMI->getOpcode() == ARM::LDM) {
+ if (PrevMI->getOpcode() == ARM::LDM_UPD ||
+ PrevMI->getOpcode() == ARM::t2LDM_UPD) {
MachineOperand &MO = PrevMI->getOperand(PrevMI->getNumOperands()-1);
- if (MO.getReg() == ARM::LR) {
- PrevMI->setDesc(TII->get(ARM::LDM_RET));
- MO.setReg(ARM::PC);
- MBB.erase(MBBI);
- return true;
- }
+ if (MO.getReg() != ARM::LR)
+ return false;
+ unsigned NewOpc = isThumb2 ? ARM::t2LDM_RET : ARM::LDM_RET;
+ PrevMI->setDesc(TII->get(NewOpc));
+ MO.setReg(ARM::PC);
+ MBB.erase(MBBI);
+ return true;
}
}
return false;
TII = TM.getInstrInfo();
TRI = TM.getRegisterInfo();
RS = new RegScavenger();
+ isThumb2 = AFI->isThumb2Function();
bool Modified = false;
for (MachineFunction::iterator MFI = Fn.begin(), E = Fn.end(); MFI != E;
delete RS;
return Modified;
}
+
+
+/// ARMPreAllocLoadStoreOpt - Pre- register allocation pass that move
+/// load / stores from consecutive locations close to make it more
+/// likely they will be combined later.
+
+namespace {
+ struct ARMPreAllocLoadStoreOpt : public MachineFunctionPass{
+ static char ID;
+ ARMPreAllocLoadStoreOpt() : MachineFunctionPass(ID) {}
+
+ const TargetData *TD;
+ const TargetInstrInfo *TII;
+ const TargetRegisterInfo *TRI;
+ const ARMSubtarget *STI;
+ MachineRegisterInfo *MRI;
+ MachineFunction *MF;
+
+ virtual bool runOnMachineFunction(MachineFunction &Fn);
+
+ virtual const char *getPassName() const {
+ return "ARM pre- register allocation load / store optimization pass";
+ }
+
+ private:
+ bool CanFormLdStDWord(MachineInstr *Op0, MachineInstr *Op1, DebugLoc &dl,
+ unsigned &NewOpc, unsigned &EvenReg,
+ unsigned &OddReg, unsigned &BaseReg,
+ unsigned &OffReg, int &Offset,
+ unsigned &PredReg, ARMCC::CondCodes &Pred,
+ bool &isT2);
+ bool RescheduleOps(MachineBasicBlock *MBB,
+ SmallVector<MachineInstr*, 4> &Ops,
+ unsigned Base, bool isLd,
+ DenseMap<MachineInstr*, unsigned> &MI2LocMap);
+ bool RescheduleLoadStoreInstrs(MachineBasicBlock *MBB);
+ };
+ char ARMPreAllocLoadStoreOpt::ID = 0;
+}
+
+bool ARMPreAllocLoadStoreOpt::runOnMachineFunction(MachineFunction &Fn) {
+ TD = Fn.getTarget().getTargetData();
+ TII = Fn.getTarget().getInstrInfo();
+ TRI = Fn.getTarget().getRegisterInfo();
+ STI = &Fn.getTarget().getSubtarget<ARMSubtarget>();
+ MRI = &Fn.getRegInfo();
+ MF = &Fn;
+
+ bool Modified = false;
+ for (MachineFunction::iterator MFI = Fn.begin(), E = Fn.end(); MFI != E;
+ ++MFI)
+ Modified |= RescheduleLoadStoreInstrs(MFI);
+
+ return Modified;
+}
+
+static bool IsSafeAndProfitableToMove(bool isLd, unsigned Base,
+ MachineBasicBlock::iterator I,
+ MachineBasicBlock::iterator E,
+ SmallPtrSet<MachineInstr*, 4> &MemOps,
+ SmallSet<unsigned, 4> &MemRegs,
+ const TargetRegisterInfo *TRI) {
+ // Are there stores / loads / calls between them?
+ // FIXME: This is overly conservative. We should make use of alias information
+ // some day.
+ SmallSet<unsigned, 4> AddedRegPressure;
+ while (++I != E) {
+ if (I->isDebugValue() || MemOps.count(&*I))
+ continue;
+ const TargetInstrDesc &TID = I->getDesc();
+ if (TID.isCall() || TID.isTerminator() || TID.hasUnmodeledSideEffects())
+ return false;
+ if (isLd && TID.mayStore())
+ return false;
+ if (!isLd) {
+ if (TID.mayLoad())
+ return false;
+ // It's not safe to move the first 'str' down.
+ // str r1, [r0]
+ // strh r5, [r0]
+ // str r4, [r0, #+4]
+ if (TID.mayStore())
+ return false;
+ }
+ for (unsigned j = 0, NumOps = I->getNumOperands(); j != NumOps; ++j) {
+ MachineOperand &MO = I->getOperand(j);
+ if (!MO.isReg())
+ continue;
+ unsigned Reg = MO.getReg();
+ if (MO.isDef() && TRI->regsOverlap(Reg, Base))
+ return false;
+ if (Reg != Base && !MemRegs.count(Reg))
+ AddedRegPressure.insert(Reg);
+ }
+ }
+
+ // Estimate register pressure increase due to the transformation.
+ if (MemRegs.size() <= 4)
+ // Ok if we are moving small number of instructions.
+ return true;
+ return AddedRegPressure.size() <= MemRegs.size() * 2;
+}
+
+bool
+ARMPreAllocLoadStoreOpt::CanFormLdStDWord(MachineInstr *Op0, MachineInstr *Op1,
+ DebugLoc &dl,
+ unsigned &NewOpc, unsigned &EvenReg,
+ unsigned &OddReg, unsigned &BaseReg,
+ unsigned &OffReg, int &Offset,
+ unsigned &PredReg,
+ ARMCC::CondCodes &Pred,
+ bool &isT2) {
+ // Make sure we're allowed to generate LDRD/STRD.
+ if (!STI->hasV5TEOps())
+ return false;
+
+ // FIXME: VLDRS / VSTRS -> VLDRD / VSTRD
+ unsigned Scale = 1;
+ unsigned Opcode = Op0->getOpcode();
+ if (Opcode == ARM::LDR)
+ NewOpc = ARM::LDRD;
+ else if (Opcode == ARM::STR)
+ NewOpc = ARM::STRD;
+ else if (Opcode == ARM::t2LDRi8 || Opcode == ARM::t2LDRi12) {
+ NewOpc = ARM::t2LDRDi8;
+ Scale = 4;
+ isT2 = true;
+ } else if (Opcode == ARM::t2STRi8 || Opcode == ARM::t2STRi12) {
+ NewOpc = ARM::t2STRDi8;
+ Scale = 4;
+ isT2 = true;
+ } else
+ return false;
+
+ // Make sure the offset registers match.
+ if (!isT2 &&
+ (Op0->getOperand(2).getReg() != Op1->getOperand(2).getReg()))
+ return false;
+
+ // Must sure the base address satisfies i64 ld / st alignment requirement.
+ if (!Op0->hasOneMemOperand() ||
+ !(*Op0->memoperands_begin())->getValue() ||
+ (*Op0->memoperands_begin())->isVolatile())
+ return false;
+
+ unsigned Align = (*Op0->memoperands_begin())->getAlignment();
+ const Function *Func = MF->getFunction();
+ unsigned ReqAlign = STI->hasV6Ops()
+ ? TD->getPrefTypeAlignment(Type::getInt64Ty(Func->getContext()))
+ : 8; // Pre-v6 need 8-byte align
+ if (Align < ReqAlign)
+ return false;
+
+ // Then make sure the immediate offset fits.
+ int OffImm = getMemoryOpOffset(Op0);
+ if (isT2) {
+ if (OffImm < 0) {
+ if (OffImm < -255)
+ // Can't fall back to t2LDRi8 / t2STRi8.
+ return false;
+ } else {
+ int Limit = (1 << 8) * Scale;
+ if (OffImm >= Limit || (OffImm & (Scale-1)))
+ return false;
+ }
+ Offset = OffImm;
+ } else {
+ ARM_AM::AddrOpc AddSub = ARM_AM::add;
+ if (OffImm < 0) {
+ AddSub = ARM_AM::sub;
+ OffImm = - OffImm;
+ }
+ int Limit = (1 << 8) * Scale;
+ if (OffImm >= Limit || (OffImm & (Scale-1)))
+ return false;
+ Offset = ARM_AM::getAM3Opc(AddSub, OffImm);
+ }
+ EvenReg = Op0->getOperand(0).getReg();
+ OddReg = Op1->getOperand(0).getReg();
+ if (EvenReg == OddReg)
+ return false;
+ BaseReg = Op0->getOperand(1).getReg();
+ if (!isT2)
+ OffReg = Op0->getOperand(2).getReg();
+ Pred = llvm::getInstrPredicate(Op0, PredReg);
+ dl = Op0->getDebugLoc();
+ return true;
+}
+
+bool ARMPreAllocLoadStoreOpt::RescheduleOps(MachineBasicBlock *MBB,
+ SmallVector<MachineInstr*, 4> &Ops,
+ unsigned Base, bool isLd,
+ DenseMap<MachineInstr*, unsigned> &MI2LocMap) {
+ bool RetVal = false;
+
+ // Sort by offset (in reverse order).
+ std::sort(Ops.begin(), Ops.end(), OffsetCompare());
+
+ // The loads / stores of the same base are in order. Scan them from first to
+ // last and check for the following:
+ // 1. Any def of base.
+ // 2. Any gaps.
+ while (Ops.size() > 1) {
+ unsigned FirstLoc = ~0U;
+ unsigned LastLoc = 0;
+ MachineInstr *FirstOp = 0;
+ MachineInstr *LastOp = 0;
+ int LastOffset = 0;
+ unsigned LastOpcode = 0;
+ unsigned LastBytes = 0;
+ unsigned NumMove = 0;
+ for (int i = Ops.size() - 1; i >= 0; --i) {
+ MachineInstr *Op = Ops[i];
+ unsigned Loc = MI2LocMap[Op];
+ if (Loc <= FirstLoc) {
+ FirstLoc = Loc;
+ FirstOp = Op;
+ }
+ if (Loc >= LastLoc) {
+ LastLoc = Loc;
+ LastOp = Op;
+ }
+
+ unsigned Opcode = Op->getOpcode();
+ if (LastOpcode && Opcode != LastOpcode)
+ break;
+
+ int Offset = getMemoryOpOffset(Op);
+ unsigned Bytes = getLSMultipleTransferSize(Op);
+ if (LastBytes) {
+ if (Bytes != LastBytes || Offset != (LastOffset + (int)Bytes))
+ break;
+ }
+ LastOffset = Offset;
+ LastBytes = Bytes;
+ LastOpcode = Opcode;
+ if (++NumMove == 8) // FIXME: Tune this limit.
+ break;
+ }
+
+ if (NumMove <= 1)
+ Ops.pop_back();
+ else {
+ SmallPtrSet<MachineInstr*, 4> MemOps;
+ SmallSet<unsigned, 4> MemRegs;
+ for (int i = NumMove-1; i >= 0; --i) {
+ MemOps.insert(Ops[i]);
+ MemRegs.insert(Ops[i]->getOperand(0).getReg());
+ }
+
+ // Be conservative, if the instructions are too far apart, don't
+ // move them. We want to limit the increase of register pressure.
+ bool DoMove = (LastLoc - FirstLoc) <= NumMove*4; // FIXME: Tune this.
+ if (DoMove)
+ DoMove = IsSafeAndProfitableToMove(isLd, Base, FirstOp, LastOp,
+ MemOps, MemRegs, TRI);
+ if (!DoMove) {
+ for (unsigned i = 0; i != NumMove; ++i)
+ Ops.pop_back();
+ } else {
+ // This is the new location for the loads / stores.
+ MachineBasicBlock::iterator InsertPos = isLd ? FirstOp : LastOp;
+ while (InsertPos != MBB->end()
+ && (MemOps.count(InsertPos) || InsertPos->isDebugValue()))
+ ++InsertPos;
+
+ // If we are moving a pair of loads / stores, see if it makes sense
+ // to try to allocate a pair of registers that can form register pairs.
+ MachineInstr *Op0 = Ops.back();
+ MachineInstr *Op1 = Ops[Ops.size()-2];
+ unsigned EvenReg = 0, OddReg = 0;
+ unsigned BaseReg = 0, OffReg = 0, PredReg = 0;
+ ARMCC::CondCodes Pred = ARMCC::AL;
+ bool isT2 = false;
+ unsigned NewOpc = 0;
+ int Offset = 0;
+ DebugLoc dl;
+ if (NumMove == 2 && CanFormLdStDWord(Op0, Op1, dl, NewOpc,
+ EvenReg, OddReg, BaseReg, OffReg,
+ Offset, PredReg, Pred, isT2)) {
+ Ops.pop_back();
+ Ops.pop_back();
+
+ // Form the pair instruction.
+ if (isLd) {
+ MachineInstrBuilder MIB = BuildMI(*MBB, InsertPos,
+ dl, TII->get(NewOpc))
+ .addReg(EvenReg, RegState::Define)
+ .addReg(OddReg, RegState::Define)
+ .addReg(BaseReg);
+ if (!isT2)
+ MIB.addReg(OffReg);
+ MIB.addImm(Offset).addImm(Pred).addReg(PredReg);
+ ++NumLDRDFormed;
+ } else {
+ MachineInstrBuilder MIB = BuildMI(*MBB, InsertPos,
+ dl, TII->get(NewOpc))
+ .addReg(EvenReg)
+ .addReg(OddReg)
+ .addReg(BaseReg);
+ if (!isT2)
+ MIB.addReg(OffReg);
+ MIB.addImm(Offset).addImm(Pred).addReg(PredReg);
+ ++NumSTRDFormed;
+ }
+ MBB->erase(Op0);
+ MBB->erase(Op1);
+
+ // Add register allocation hints to form register pairs.
+ MRI->setRegAllocationHint(EvenReg, ARMRI::RegPairEven, OddReg);
+ MRI->setRegAllocationHint(OddReg, ARMRI::RegPairOdd, EvenReg);
+ } else {
+ for (unsigned i = 0; i != NumMove; ++i) {
+ MachineInstr *Op = Ops.back();
+ Ops.pop_back();
+ MBB->splice(InsertPos, MBB, Op);
+ }
+ }
+
+ NumLdStMoved += NumMove;
+ RetVal = true;
+ }
+ }
+ }
+
+ return RetVal;
+}
+
+bool
+ARMPreAllocLoadStoreOpt::RescheduleLoadStoreInstrs(MachineBasicBlock *MBB) {
+ bool RetVal = false;
+
+ DenseMap<MachineInstr*, unsigned> MI2LocMap;
+ DenseMap<unsigned, SmallVector<MachineInstr*, 4> > Base2LdsMap;
+ DenseMap<unsigned, SmallVector<MachineInstr*, 4> > Base2StsMap;
+ SmallVector<unsigned, 4> LdBases;
+ SmallVector<unsigned, 4> StBases;
+
+ unsigned Loc = 0;
+ MachineBasicBlock::iterator MBBI = MBB->begin();
+ MachineBasicBlock::iterator E = MBB->end();
+ while (MBBI != E) {
+ for (; MBBI != E; ++MBBI) {
+ MachineInstr *MI = MBBI;
+ const TargetInstrDesc &TID = MI->getDesc();
+ if (TID.isCall() || TID.isTerminator()) {
+ // Stop at barriers.
+ ++MBBI;
+ break;
+ }
+
+ if (!MI->isDebugValue())
+ MI2LocMap[MI] = ++Loc;
+
+ if (!isMemoryOp(MI))
+ continue;
+ unsigned PredReg = 0;
+ if (llvm::getInstrPredicate(MI, PredReg) != ARMCC::AL)
+ continue;
+
+ int Opc = MI->getOpcode();
+ bool isLd = isi32Load(Opc) || Opc == ARM::VLDRS || Opc == ARM::VLDRD;
+ unsigned Base = MI->getOperand(1).getReg();
+ int Offset = getMemoryOpOffset(MI);
+
+ bool StopHere = false;
+ if (isLd) {
+ DenseMap<unsigned, SmallVector<MachineInstr*, 4> >::iterator BI =
+ Base2LdsMap.find(Base);
+ if (BI != Base2LdsMap.end()) {
+ for (unsigned i = 0, e = BI->second.size(); i != e; ++i) {
+ if (Offset == getMemoryOpOffset(BI->second[i])) {
+ StopHere = true;
+ break;
+ }
+ }
+ if (!StopHere)
+ BI->second.push_back(MI);
+ } else {
+ SmallVector<MachineInstr*, 4> MIs;
+ MIs.push_back(MI);
+ Base2LdsMap[Base] = MIs;
+ LdBases.push_back(Base);
+ }
+ } else {
+ DenseMap<unsigned, SmallVector<MachineInstr*, 4> >::iterator BI =
+ Base2StsMap.find(Base);
+ if (BI != Base2StsMap.end()) {
+ for (unsigned i = 0, e = BI->second.size(); i != e; ++i) {
+ if (Offset == getMemoryOpOffset(BI->second[i])) {
+ StopHere = true;
+ break;
+ }
+ }
+ if (!StopHere)
+ BI->second.push_back(MI);
+ } else {
+ SmallVector<MachineInstr*, 4> MIs;
+ MIs.push_back(MI);
+ Base2StsMap[Base] = MIs;
+ StBases.push_back(Base);
+ }
+ }
+
+ if (StopHere) {
+ // Found a duplicate (a base+offset combination that's seen earlier).
+ // Backtrack.
+ --Loc;
+ break;
+ }
+ }
+
+ // Re-schedule loads.
+ for (unsigned i = 0, e = LdBases.size(); i != e; ++i) {
+ unsigned Base = LdBases[i];
+ SmallVector<MachineInstr*, 4> &Lds = Base2LdsMap[Base];
+ if (Lds.size() > 1)
+ RetVal |= RescheduleOps(MBB, Lds, Base, true, MI2LocMap);
+ }
+
+ // Re-schedule stores.
+ for (unsigned i = 0, e = StBases.size(); i != e; ++i) {
+ unsigned Base = StBases[i];
+ SmallVector<MachineInstr*, 4> &Sts = Base2StsMap[Base];
+ if (Sts.size() > 1)
+ RetVal |= RescheduleOps(MBB, Sts, Base, false, MI2LocMap);
+ }
+
+ if (MBBI != E) {
+ Base2LdsMap.clear();
+ Base2StsMap.clear();
+ LdBases.clear();
+ StBases.clear();
+ }
+ }
+
+ return RetVal;
+}
+
+
+/// createARMLoadStoreOptimizationPass - returns an instance of the load / store
+/// optimization pass.
+FunctionPass *llvm::createARMLoadStoreOptimizationPass(bool PreAlloc) {
+ if (PreAlloc)
+ return new ARMPreAllocLoadStoreOpt();
+ return new ARMLoadStoreOpt();
+}
projects / oota-llvm.git / blobdiff