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)
if (AFI->getGPRCalleeSavedArea1Size()) MBBI++;
}
- fixTCReturn(MF, MBB);
-
if (ArgRegsSaveSize)
emitSPUpdate(isARM, MBB, MBBI, dl, TII, ArgRegsSaveSize);
}
// 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;
}
}
MachineBasicBlock *GetMBB = MF.CreateMachineBasicBlock();
MachineBasicBlock *McrMBB = MF.CreateMachineBasicBlock();
+ // 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 (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);
+ for (MachineBasicBlock *PredBB : BeforePrologueRegion)
+ PredBB->addLiveIn(*i);
}
- 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);