-//===- ARMBaseRegisterInfo.cpp - ARM Register Information -----------*- C++ -*-===//
+//===- ARMBaseRegisterInfo.cpp - ARM Register Information -------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
return Reserved;
}
-bool
-ARMBaseRegisterInfo::isReservedReg(const MachineFunction &MF, unsigned Reg) const {
+bool ARMBaseRegisterInfo::isReservedReg(const MachineFunction &MF,
+ unsigned Reg) const {
switch (Reg) {
default: break;
case ARM::SP:
return false;
}
-const TargetRegisterClass *ARMBaseRegisterInfo::getPointerRegClass() const {
- return &ARM::GPRRegClass;
+const TargetRegisterClass *
+ARMBaseRegisterInfo::getPointerRegClass(unsigned Kind) const {
+ return ARM::GPRRegisterClass;
}
/// getAllocationOrder - Returns the register allocation order for a specified
MFI->isFrameAddressTaken());
}
+bool ARMBaseRegisterInfo::cannotEliminateFrame(const MachineFunction &MF) const {
+ const MachineFrameInfo *MFI = MF.getFrameInfo();
+ if (NoFramePointerElim && MFI->hasCalls())
+ return true;
+ return MFI->hasVarSizedObjects() || MFI->isFrameAddressTaken();
+}
+
+/// estimateStackSize - Estimate and return the size of the frame.
static unsigned estimateStackSize(MachineFunction &MF, MachineFrameInfo *MFI) {
const MachineFrameInfo *FFI = MF.getFrameInfo();
int Offset = 0;
return (unsigned)Offset;
}
+/// estimateRSStackSizeLimit - Look at each instruction that references stack
+/// frames and return the stack size limit beyond which some of these
+/// instructions will require scratch register during their expansion later.
+unsigned
+ARMBaseRegisterInfo::estimateRSStackSizeLimit(MachineFunction &MF) const {
+ unsigned Limit = (1 << 12) - 1;
+ for (MachineFunction::iterator BB = MF.begin(),E = MF.end(); BB != E; ++BB) {
+ for (MachineBasicBlock::iterator I = BB->begin(), E = BB->end();
+ I != E; ++I) {
+ for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
+ if (!I->getOperand(i).isFI()) continue;
+
+ const TargetInstrDesc &Desc = TII.get(I->getOpcode());
+ unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
+ if (AddrMode == ARMII::AddrMode3 ||
+ AddrMode == ARMII::AddrModeT2_i8)
+ return (1 << 8) - 1;
+
+ if (AddrMode == ARMII::AddrMode5 ||
+ AddrMode == ARMII::AddrModeT2_i8s4)
+ Limit = std::min(Limit, ((1U << 8) - 1) * 4);
+
+ if (AddrMode == ARMII::AddrModeT2_i12 && hasFP(MF))
+ // When the stack offset is negative, we will end up using
+ // the i8 instructions instead.
+ return (1 << 8) - 1;
+ break; // At most one FI per instruction
+ }
+ }
+ }
+
+ return Limit;
+}
+
void
ARMBaseRegisterInfo::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
RegScavenger *RS) const {
}
}
- if (CSRegClasses[i] == &ARM::GPRRegClass) {
+ if (CSRegClasses[i] == ARM::GPRRegisterClass) {
if (Spilled) {
NumGPRSpills++;
}
bool ExtraCSSpill = false;
- if (!CanEliminateFrame || hasFP(MF)) {
+ if (!CanEliminateFrame || cannotEliminateFrame(MF)) {
AFI->setHasStackFrame(true);
// If LR is not spilled, but at least one of R4, R5, R6, and R7 is spilled.
// register scavenging.
if (RS && !ExtraCSSpill && !AFI->isThumb1OnlyFunction()) {
MachineFrameInfo *MFI = MF.getFrameInfo();
- unsigned Size = estimateStackSize(MF, MFI);
- unsigned Limit = (1 << 12) - 1;
- for (MachineFunction::iterator BB = MF.begin(),E = MF.end();BB != E; ++BB)
- for (MachineBasicBlock::iterator I= BB->begin(); I != BB->end(); ++I) {
- for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i)
- if (I->getOperand(i).isFI()) {
- unsigned Opcode = I->getOpcode();
- const TargetInstrDesc &Desc = TII.get(Opcode);
- unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
- if (AddrMode == ARMII::AddrMode3) {
- Limit = (1 << 8) - 1;
- goto DoneEstimating;
- } else if (AddrMode == ARMII::AddrMode5) {
- unsigned ThisLimit = ((1 << 8) - 1) * 4;
- if (ThisLimit < Limit)
- Limit = ThisLimit;
- }
- }
- }
- DoneEstimating:
- if (Size >= Limit) {
+ if (estimateStackSize(MF, MFI) >= estimateRSStackSizeLimit(MF)) {
// If any non-reserved CS register isn't spilled, just spill one or two
// extra. That should take care of it!
unsigned NumExtras = TargetAlign / 4;
}
} else {
// Reserve a slot closest to SP or frame pointer.
- const TargetRegisterClass *RC = &ARM::GPRRegClass;
+ const TargetRegisterClass *RC = ARM::GPRRegisterClass;
RS->setScavengingFrameIndex(MFI->CreateStackObject(RC->getSize(),
RC->getAlignment()));
}
unsigned PredReg) const {
MachineFunction &MF = *MBB.getParent();
MachineConstantPool *ConstantPool = MF.getConstantPool();
- Constant *C = ConstantInt::get(Type::Int32Ty, Val);
+ Constant *C =
+ ConstantInt::get(Type::getInt32Ty(MF.getFunction()->getContext()), Val);
unsigned Idx = ConstantPool->getConstantPoolIndex(C, 4);
BuildMI(MBB, MBBI, dl, TII.get(ARM::LDRcp))
static
unsigned findScratchRegister(RegScavenger *RS, const TargetRegisterClass *RC,
ARMFunctionInfo *AFI) {
- unsigned Reg = RS ? RS->FindUnusedReg(RC, true) : (unsigned) ARM::R12;
+ unsigned Reg = RS ? RS->FindUnusedReg(RC) : (unsigned) ARM::R12;
assert(!AFI->isThumb1OnlyFunction());
- if (Reg == 0)
- // Try a already spilled CS register.
- Reg = RS->FindUnusedReg(RC, AFI->getSpilledCSRegisters());
-
return Reg;
}
MachineInstr &MI = *II;
MachineBasicBlock &MBB = *MI.getParent();
MachineFunction &MF = *MBB.getParent();
+ const MachineFrameInfo *MFI = MF.getFrameInfo();
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
assert(!AFI->isThumb1OnlyFunction() &&
- "This eliminateFrameIndex does not suppor Thumb1!");
+ "This eliminateFrameIndex does not support Thumb1!");
while (!MI.getOperand(i).isFI()) {
++i;
unsigned FrameReg = ARM::SP;
int FrameIndex = MI.getOperand(i).getIndex();
- int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex) +
- MF.getFrameInfo()->getStackSize() + SPAdj;
+ int Offset = MFI->getObjectOffset(FrameIndex) + MFI->getStackSize() + SPAdj;
if (AFI->isGPRCalleeSavedArea1Frame(FrameIndex))
Offset -= AFI->getGPRCalleeSavedArea1Offset();
Offset -= AFI->getGPRCalleeSavedArea2Offset();
else if (AFI->isDPRCalleeSavedAreaFrame(FrameIndex))
Offset -= AFI->getDPRCalleeSavedAreaOffset();
- else if (hasFP(MF)) {
- assert(SPAdj == 0 && "Unexpected");
- // There is alloca()'s in this function, must reference off the frame
- // pointer instead.
+ else if (hasFP(MF) && AFI->hasStackFrame()) {
+ assert(SPAdj == 0 && "Unexpected stack offset!");
+ // Use frame pointer to reference fixed objects unless this is a
+ // frameless function,
FrameReg = getFrameRegister(MF);
Offset -= AFI->getFramePtrSpillOffset();
}
// modify MI as necessary to handle as much of 'Offset' as possible
+ bool Done = false;
if (!AFI->isThumbFunction())
- Offset = rewriteARMFrameIndex(MI, i, FrameReg, Offset, TII);
+ Done = rewriteARMFrameIndex(MI, i, FrameReg, Offset, TII);
else {
assert(AFI->isThumb2Function());
- Offset = rewriteT2FrameIndex(MI, i, FrameReg, Offset, TII);
+ Done = rewriteT2FrameIndex(MI, i, FrameReg, Offset, TII);
}
- if (Offset == 0)
+ if (Done)
return;
// If we get here, the immediate doesn't fit into the instruction. We folded
// as much as possible above, handle the rest, providing a register that is
// SP+LargeImm.
- assert(Offset && "This code isn't needed if offset already handled!");
+ assert((Offset ||
+ (MI.getDesc().TSFlags & ARMII::AddrModeMask) == ARMII::AddrMode4) &&
+ "This code isn't needed if offset already handled!");
// Insert a set of r12 with the full address: r12 = sp + offset
// If the offset we have is too large to fit into the instruction, we need
// to form it with a series of ADDri's. Do this by taking 8-bit chunks
// out of 'Offset'.
- unsigned ScratchReg = findScratchRegister(RS, &ARM::GPRRegClass, AFI);
+ unsigned ScratchReg = findScratchRegister(RS, ARM::GPRRegisterClass, AFI);
if (ScratchReg == 0)
// No register is "free". Scavenge a register.
- ScratchReg = RS->scavengeRegister(&ARM::GPRRegClass, II, SPAdj);
+ ScratchReg = RS->scavengeRegister(ARM::GPRRegisterClass, II, SPAdj);
int PIdx = MI.findFirstPredOperandIdx();
ARMCC::CondCodes Pred = (PIdx == -1)
? ARMCC::AL : (ARMCC::CondCodes)MI.getOperand(PIdx).getImm();
unsigned PredReg = (PIdx == -1) ? 0 : MI.getOperand(PIdx+1).getReg();
- if (!AFI->isThumbFunction())
- emitARMRegPlusImmediate(MBB, II, MI.getDebugLoc(), ScratchReg, FrameReg,
- Offset, Pred, PredReg, TII);
+ if (Offset == 0)
+ // Must be addrmode4.
+ MI.getOperand(i).ChangeToRegister(FrameReg, false, false, false);
else {
- assert(AFI->isThumb2Function());
- emitT2RegPlusImmediate(MBB, II, MI.getDebugLoc(), ScratchReg, FrameReg,
- Offset, Pred, PredReg, TII);
+ if (!AFI->isThumbFunction())
+ emitARMRegPlusImmediate(MBB, II, MI.getDebugLoc(), ScratchReg, FrameReg,
+ Offset, Pred, PredReg, TII);
+ else {
+ assert(AFI->isThumb2Function());
+ emitT2RegPlusImmediate(MBB, II, MI.getDebugLoc(), ScratchReg, FrameReg,
+ Offset, Pred, PredReg, TII);
+ }
+ MI.getOperand(i).ChangeToRegister(ScratchReg, false, false, true);
}
- MI.getOperand(i).ChangeToRegister(ScratchReg, false, false, true);
}
/// Move iterator pass the next bunch of callee save load / store ops for
}
static bool isCSRestore(MachineInstr *MI,
- const ARMBaseInstrInfo &TII,
+ const ARMBaseInstrInfo &TII,
const unsigned *CSRegs) {
return ((MI->getOpcode() == (int)ARM::FLDD ||
MI->getOpcode() == (int)ARM::LDR ||
// Darwin ABI requires FP to point to the stack slot that contains the
// previous FP.
- if ((STI.isTargetDarwin() && NumBytes) || hasFP(MF)) {
+ bool HasFP = hasFP(MF);
+ if ((STI.isTargetDarwin() && NumBytes) || HasFP) {
NumBytes = AFI->getFramePtrSpillOffset() - NumBytes;
// Reset SP based on frame pointer only if the stack frame extends beyond
// frame pointer stack slot or target is ELF and the function has FP.
- if (AFI->getGPRCalleeSavedArea2Size() ||
+ if (HasFP ||
+ AFI->getGPRCalleeSavedArea2Size() ||
AFI->getDPRCalleeSavedAreaSize() ||
- AFI->getDPRCalleeSavedAreaOffset()||
- hasFP(MF)) {
+ AFI->getDPRCalleeSavedAreaOffset()) {
if (NumBytes) {
- unsigned SUBriOpc = isARM ? ARM::SUBri : ARM::t2SUBri;
- BuildMI(MBB, MBBI, dl, TII.get(SUBriOpc), ARM::SP)
- .addReg(FramePtr)
- .addImm(NumBytes)
- .addImm((unsigned)ARMCC::AL).addReg(0).addReg(0);
+ if (isARM)
+ emitARMRegPlusImmediate(MBB, MBBI, dl, ARM::SP, FramePtr, -NumBytes,
+ ARMCC::AL, 0, TII);
+ else
+ emitT2RegPlusImmediate(MBB, MBBI, dl, ARM::SP, FramePtr, -NumBytes,
+ ARMCC::AL, 0, TII);
} else {
// Thumb2 or ARM.
- unsigned MOVrOpc = isARM ? ARM::MOVr : ARM::t2MOVr;
- BuildMI(MBB, MBBI, dl, TII.get(MOVrOpc), ARM::SP)
- .addReg(FramePtr)
- .addImm((unsigned)ARMCC::AL).addReg(0).addReg(0);
+ if (isARM)
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::MOVr), ARM::SP)
+ .addReg(FramePtr)
+ .addImm((unsigned)ARMCC::AL).addReg(0).addReg(0);
+ else
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVgpr2gpr), ARM::SP)
+ .addReg(FramePtr);
}
}
} else if (NumBytes)
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