}
}
};
-} // namespace
+}
/// Emit an instruction sequence that will align the address in
/// register Reg by zero-ing out the lower bits. For versions of the
void ARMFrameLowering::emitPrologue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
- assert(&MBB == &MF.front() && "Shrink-wrapping not yet implemented");
MachineBasicBlock::iterator MBBI = MBB.begin();
MachineFrameInfo *MFI = MF.getFrameInfo();
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
AFI->setShouldRestoreSPFromFP(true);
}
-// Resolve TCReturn pseudo-instruction
-void ARMFrameLowering::fixTCReturn(MachineFunction &MF,
- MachineBasicBlock &MBB) const {
- MachineBasicBlock::iterator MBBI = MBB.getLastNonDebugInstr();
- assert(MBBI->isReturn() && "Can only insert epilog into returning blocks");
- unsigned RetOpcode = MBBI->getOpcode();
- DebugLoc dl = MBBI->getDebugLoc();
- const ARMBaseInstrInfo &TII =
- *static_cast<const ARMBaseInstrInfo *>(MF.getSubtarget().getInstrInfo());
-
- if (!(RetOpcode == ARM::TCRETURNdi || RetOpcode == ARM::TCRETURNri))
- return;
-
- // Tail call return: adjust the stack pointer and jump to callee.
- MBBI = MBB.getLastNonDebugInstr();
- MachineOperand &JumpTarget = MBBI->getOperand(0);
-
- // Jump to label or value in register.
- if (RetOpcode == ARM::TCRETURNdi) {
- unsigned TCOpcode = STI.isThumb() ?
- (STI.isTargetMachO() ? ARM::tTAILJMPd : ARM::tTAILJMPdND) :
- ARM::TAILJMPd;
- MachineInstrBuilder MIB = BuildMI(MBB, MBBI, dl, TII.get(TCOpcode));
- if (JumpTarget.isGlobal())
- MIB.addGlobalAddress(JumpTarget.getGlobal(), JumpTarget.getOffset(),
- JumpTarget.getTargetFlags());
- else {
- assert(JumpTarget.isSymbol());
- MIB.addExternalSymbol(JumpTarget.getSymbolName(),
- JumpTarget.getTargetFlags());
- }
-
- // Add the default predicate in Thumb mode.
- if (STI.isThumb()) MIB.addImm(ARMCC::AL).addReg(0);
- } else if (RetOpcode == ARM::TCRETURNri) {
- BuildMI(MBB, MBBI, dl,
- TII.get(STI.isThumb() ? ARM::tTAILJMPr : ARM::TAILJMPr)).
- addReg(JumpTarget.getReg(), RegState::Kill);
- }
-
- MachineInstr *NewMI = std::prev(MBBI);
- for (unsigned i = 1, e = MBBI->getNumOperands(); i != e; ++i)
- NewMI->addOperand(MBBI->getOperand(i));
-
- // Delete the pseudo instruction TCRETURN.
- MBB.erase(MBBI);
- MBBI = NewMI;
-}
-
void ARMFrameLowering::emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
- MachineBasicBlock::iterator MBBI = MBB.getLastNonDebugInstr();
- assert(MBBI->isReturn() && "Can only insert epilog into returning blocks");
- DebugLoc dl = MBBI->getDebugLoc();
MachineFrameInfo *MFI = MF.getFrameInfo();
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
const TargetRegisterInfo *RegInfo = MF.getSubtarget().getRegisterInfo();
// All calls are tail calls in GHC calling conv, and functions have no
// prologue/epilogue.
- if (MF.getFunction()->getCallingConv() == CallingConv::GHC) {
- fixTCReturn(MF, MBB);
+ if (MF.getFunction()->getCallingConv() == CallingConv::GHC)
return;
- }
+
+ // First put ourselves on the first (from top) terminator instructions.
+ MachineBasicBlock::iterator MBBI = MBB.getFirstTerminator();
+ DebugLoc dl = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
if (!AFI->hasStackFrame()) {
if (NumBytes - ArgRegsSaveSize != 0)
// This is bad, if an interrupt is taken after the mov, sp is in an
// inconsistent state.
// Use the first callee-saved register as a scratch register.
- assert(MF.getRegInfo().isPhysRegUsed(ARM::R4) &&
+ assert(!MFI->getPristineRegs(MF).test(ARM::R4) &&
"No scratch register to restore SP from FP!");
emitT2RegPlusImmediate(MBB, MBBI, dl, ARM::R4, FramePtr, -NumBytes,
ARMCC::AL, 0, TII);
if (AFI->getGPRCalleeSavedArea1Size()) MBBI++;
}
- fixTCReturn(MF, MBB);
-
if (ArgRegsSaveSize)
emitSPUpdate(isARM, MBB, MBBI, dl, TII, ArgRegsSaveSize);
}
return Offset;
}
-int ARMFrameLowering::getFrameIndexOffset(const MachineFunction &MF,
- int FI) const {
- unsigned FrameReg;
- return getFrameIndexReference(MF, FI, FrameReg);
-}
-
void ARMFrameLowering::emitPushInst(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
const std::vector<CalleeSavedInfo> &CSI,
// Put any subsequent vpush instructions before this one: they will refer to
// higher register numbers so need to be pushed first in order to preserve
// monotonicity.
- --MI;
+ if (MI != MBB.begin())
+ --MI;
}
}
MachineFunction &MF = *MBB.getParent();
const TargetInstrInfo &TII = *MF.getSubtarget().getInstrInfo();
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
- DebugLoc DL = MI->getDebugLoc();
- unsigned RetOpcode = MI->getOpcode();
- bool isTailCall = (RetOpcode == ARM::TCRETURNdi ||
- RetOpcode == ARM::TCRETURNri);
- bool isInterrupt =
- RetOpcode == ARM::SUBS_PC_LR || RetOpcode == ARM::t2SUBS_PC_LR;
+ DebugLoc DL;
+ bool isTailCall = false;
+ bool isInterrupt = false;
+ if (MBB.end() != MI) {
+ DL = MI->getDebugLoc();
+ unsigned RetOpcode = MI->getOpcode();
+ isTailCall = (RetOpcode == ARM::TCRETURNdi || RetOpcode == ARM::TCRETURNri);
+ isInterrupt =
+ RetOpcode == ARM::SUBS_PC_LR || RetOpcode == ARM::t2SUBS_PC_LR;
+ }
SmallVector<unsigned, 4> Regs;
unsigned i = CSI.size();
if (Reg == ARM::LR && !isTailCall && !isVarArg && !isInterrupt &&
STI.hasV5TOps()) {
- Reg = ARM::PC;
- LdmOpc = AFI->isThumbFunction() ? ARM::t2LDMIA_RET : ARM::LDMIA_RET;
+ if (MBB.succ_empty()) {
+ Reg = ARM::PC;
+ DeleteRet = true;
+ LdmOpc = AFI->isThumbFunction() ? ARM::t2LDMIA_RET : ARM::LDMIA_RET;
+ } else
+ LdmOpc = AFI->isThumbFunction() ? ARM::t2LDMIA_UPD : ARM::LDMIA_UPD;
// Fold the return instruction into the LDM.
- DeleteRet = true;
}
// If NoGap is true, pop consecutive registers and then leave the rest
.addReg(ARM::SP));
for (unsigned i = 0, e = Regs.size(); i < e; ++i)
MIB.addReg(Regs[i], getDefRegState(true));
- if (DeleteRet) {
+ if (DeleteRet && MI != MBB.end()) {
MIB.copyImplicitOps(&*MI);
MI->eraseFromParent();
}
// Put any subsequent vpop instructions after this one: they will refer to
// higher register numbers so need to be popped afterwards.
- ++MI;
+ if (MI != MBB.end())
+ ++MI;
}
}
// callee-saved vector registers after realigning the stack. The vst1 and vld1
// instructions take alignment hints that can improve performance.
//
-static void checkNumAlignedDPRCS2Regs(MachineFunction &MF) {
+static void
+checkNumAlignedDPRCS2Regs(MachineFunction &MF, BitVector &SavedRegs) {
MF.getInfo<ARMFunctionInfo>()->setNumAlignedDPRCS2Regs(0);
if (!SpillAlignedNEONRegs)
return;
// callee-saved registers in order, but it can happen that there are holes in
// the range. Registers above the hole will be spilled to the standard DPRCS
// area.
- MachineRegisterInfo &MRI = MF.getRegInfo();
unsigned NumSpills = 0;
for (; NumSpills < 8; ++NumSpills)
- if (!MRI.isPhysRegUsed(ARM::D8 + NumSpills))
+ if (!SavedRegs.test(ARM::D8 + NumSpills))
break;
// Don't do this for just one d-register. It's not worth it.
MF.getInfo<ARMFunctionInfo>()->setNumAlignedDPRCS2Regs(NumSpills);
// A scratch register is required for the vst1 / vld1 instructions.
- MF.getRegInfo().setPhysRegUsed(ARM::R4);
+ SavedRegs.set(ARM::R4);
}
-void
-ARMFrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
- RegScavenger *RS) const {
+void ARMFrameLowering::determineCalleeSaves(MachineFunction &MF,
+ BitVector &SavedRegs,
+ RegScavenger *RS) const {
+ TargetFrameLowering::determineCalleeSaves(MF, SavedRegs, RS);
// This tells PEI to spill the FP as if it is any other callee-save register
// to take advantage the eliminateFrameIndex machinery. This also ensures it
// is spilled in the order specified by getCalleeSavedRegs() to make it easier
// FIXME: It will be better just to find spare register here.
if (AFI->isThumb2Function() &&
(MFI->hasVarSizedObjects() || RegInfo->needsStackRealignment(MF)))
- MRI.setPhysRegUsed(ARM::R4);
+ SavedRegs.set(ARM::R4);
if (AFI->isThumb1OnlyFunction()) {
// Spill LR if Thumb1 function uses variable length argument lists.
if (AFI->getArgRegsSaveSize() > 0)
- MRI.setPhysRegUsed(ARM::LR);
+ SavedRegs.set(ARM::LR);
// Spill R4 if Thumb1 epilogue has to restore SP from FP. We don't know
// for sure what the stack size will be, but for this, an estimate is good
// FIXME: It will be better just to find spare register here.
unsigned StackSize = MFI->estimateStackSize(MF);
if (MFI->hasVarSizedObjects() || StackSize > 508)
- MRI.setPhysRegUsed(ARM::R4);
+ SavedRegs.set(ARM::R4);
}
// See if we can spill vector registers to aligned stack.
- checkNumAlignedDPRCS2Regs(MF);
+ checkNumAlignedDPRCS2Regs(MF, SavedRegs);
// Spill the BasePtr if it's used.
if (RegInfo->hasBasePointer(MF))
- MRI.setPhysRegUsed(RegInfo->getBaseRegister());
+ SavedRegs.set(RegInfo->getBaseRegister());
// Don't spill FP if the frame can be eliminated. This is determined
- // by scanning the callee-save registers to see if any is used.
+ // by scanning the callee-save registers to see if any is modified.
const MCPhysReg *CSRegs = RegInfo->getCalleeSavedRegs(&MF);
for (unsigned i = 0; CSRegs[i]; ++i) {
unsigned Reg = CSRegs[i];
bool Spilled = false;
- if (MRI.isPhysRegUsed(Reg)) {
+ if (SavedRegs.test(Reg)) {
Spilled = true;
CanEliminateFrame = false;
}
// If LR is not spilled, but at least one of R4, R5, R6, and R7 is spilled.
// Spill LR as well so we can fold BX_RET to the registers restore (LDM).
if (!LRSpilled && CS1Spilled) {
- MRI.setPhysRegUsed(ARM::LR);
+ SavedRegs.set(ARM::LR);
NumGPRSpills++;
SmallVectorImpl<unsigned>::iterator LRPos;
LRPos = std::find(UnspilledCS1GPRs.begin(), UnspilledCS1GPRs.end(),
}
if (hasFP(MF)) {
- MRI.setPhysRegUsed(FramePtr);
+ SavedRegs.set(FramePtr);
auto FPPos = std::find(UnspilledCS1GPRs.begin(), UnspilledCS1GPRs.end(),
FramePtr);
if (FPPos != UnspilledCS1GPRs.end())
// Don't spill high register if the function is thumb
if (!AFI->isThumbFunction() ||
isARMLowRegister(Reg) || Reg == ARM::LR) {
- MRI.setPhysRegUsed(Reg);
+ SavedRegs.set(Reg);
if (!MRI.isReserved(Reg))
ExtraCSSpill = true;
break;
}
} else if (!UnspilledCS2GPRs.empty() && !AFI->isThumb1OnlyFunction()) {
unsigned Reg = UnspilledCS2GPRs.front();
- MRI.setPhysRegUsed(Reg);
+ SavedRegs.set(Reg);
if (!MRI.isReserved(Reg))
ExtraCSSpill = true;
}
}
if (Extras.size() && NumExtras == 0) {
for (unsigned i = 0, e = Extras.size(); i != e; ++i) {
- MRI.setPhysRegUsed(Extras[i]);
+ SavedRegs.set(Extras[i]);
}
} else if (!AFI->isThumb1OnlyFunction()) {
// note: Thumb1 functions spill to R12, not the stack. Reserve a slot
}
if (ForceLRSpill) {
- MRI.setPhysRegUsed(ARM::LR);
+ SavedRegs.set(ARM::LR);
AFI->setLRIsSpilledForFarJump(true);
}
}
// We need to keep the stack aligned properly. To do this, we round the
// amount of space needed for the outgoing arguments up to the next
// alignment boundary.
- unsigned Align = getStackAlignment();
- Amount = (Amount+Align-1)/Align*Align;
+ Amount = alignSPAdjust(Amount);
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
assert(!AFI->isThumb1OnlyFunction() &&
if (!ST->isTargetAndroid() && !ST->isTargetLinux())
report_fatal_error("Segmented stacks not supported on this platform.");
- assert(&PrologueMBB == &MF.front() && "Shrink-wrapping not yet implemented");
MachineFrameInfo *MFI = MF.getFrameInfo();
MachineModuleInfo &MMI = MF.getMMI();
MCContext &Context = MMI.getContext();
MachineBasicBlock *GetMBB = MF.CreateMachineBasicBlock();
MachineBasicBlock *McrMBB = MF.CreateMachineBasicBlock();
- for (MachineBasicBlock::livein_iterator i = PrologueMBB.livein_begin(),
- e = PrologueMBB.livein_end();
- i != e; ++i) {
- AllocMBB->addLiveIn(*i);
- GetMBB->addLiveIn(*i);
- McrMBB->addLiveIn(*i);
- PrevStackMBB->addLiveIn(*i);
- PostStackMBB->addLiveIn(*i);
+ // Grab everything that reaches PrologueMBB to update there liveness as well.
+ SmallPtrSet<MachineBasicBlock *, 8> BeforePrologueRegion;
+ SmallVector<MachineBasicBlock *, 2> WalkList;
+ WalkList.push_back(&PrologueMBB);
+
+ do {
+ MachineBasicBlock *CurMBB = WalkList.pop_back_val();
+ for (MachineBasicBlock *PredBB : CurMBB->predecessors()) {
+ if (BeforePrologueRegion.insert(PredBB).second)
+ WalkList.push_back(PredBB);
+ }
+ } while (!WalkList.empty());
+
+ // The order in that list is important.
+ // The blocks will all be inserted before PrologueMBB using that order.
+ // Therefore the block that should appear first in the CFG should appear
+ // first in the list.
+ MachineBasicBlock *AddedBlocks[] = {PrevStackMBB, McrMBB, GetMBB, AllocMBB,
+ PostStackMBB};
+ const int NbAddedBlocks = sizeof(AddedBlocks) / sizeof(AddedBlocks[0]);
+
+ for (int Idx = 0; Idx < NbAddedBlocks; ++Idx)
+ BeforePrologueRegion.insert(AddedBlocks[Idx]);
+
+ for (const auto &LI : PrologueMBB.liveins()) {
+ for (MachineBasicBlock *PredBB : BeforePrologueRegion)
+ PredBB->addLiveIn(LI);
}
- MF.push_front(PostStackMBB);
- MF.push_front(AllocMBB);
- MF.push_front(GetMBB);
- MF.push_front(McrMBB);
- MF.push_front(PrevStackMBB);
+ // Remove the newly added blocks from the list, since we know
+ // we do not have to do the following updates for them.
+ for (int Idx = 0; Idx < NbAddedBlocks; ++Idx) {
+ BeforePrologueRegion.erase(AddedBlocks[Idx]);
+ MF.insert(&PrologueMBB, AddedBlocks[Idx]);
+ }
+
+ for (MachineBasicBlock *MBB : BeforePrologueRegion) {
+ // Make sure the LiveIns are still sorted and unique.
+ MBB->sortUniqueLiveIns();
+ // Replace the edges to PrologueMBB by edges to the sequences
+ // we are about to add.
+ MBB->ReplaceUsesOfBlockWith(&PrologueMBB, AddedBlocks[0]);
+ }
// The required stack size that is aligned to ARM constant criterion.
AlignedStackSize = alignToARMConstant(StackSize);