-//===- ARMBaseRegisterInfo.cpp - ARM Register Information -----------*- C++ -*-===//
+//===- ARMBaseRegisterInfo.cpp - ARM Register Information -------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
#include "llvm/CodeGen/MachineLocation.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RegisterScavenging.h"
+#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetFrameInfo.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/CommandLine.h"
using namespace llvm;
+cl::opt<bool>
+ReuseFrameIndexVals("arm-reuse-frame-index-vals", cl::Hidden, cl::init(true),
+ cl::desc("Reuse repeated frame index values"));
+
unsigned ARMBaseRegisterInfo::getRegisterNumbering(unsigned RegEnum,
bool *isSPVFP) {
if (isSPVFP)
FramePtr((STI.isTargetDarwin() || STI.isThumb()) ? ARM::R7 : ARM::R11) {
}
-unsigned ARMBaseRegisterInfo::
-getOpcode(int Op) const {
- return TII.getOpcode((ARMII::Op)Op);
-}
-
const unsigned*
ARMBaseRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
static const unsigned CalleeSavedRegs[] = {
? DarwinCalleeSavedRegClasses : CalleeSavedRegClasses;
}
-BitVector ARMBaseRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
+BitVector ARMBaseRegisterInfo::
+getReservedRegs(const MachineFunction &MF) const {
// FIXME: avoid re-calculating this everytime.
BitVector Reserved(getNumRegs());
Reserved.set(ARM::SP);
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::getMatchingSuperRegClass(const TargetRegisterClass *A,
+ const TargetRegisterClass *B,
+ unsigned SubIdx) const {
+ switch (SubIdx) {
+ default: return 0;
+ case 1:
+ case 2:
+ case 3:
+ case 4:
+ // S sub-registers.
+ if (A->getSize() == 8) {
+ if (B == &ARM::SPR_8RegClass)
+ return &ARM::DPR_8RegClass;
+ assert(B == &ARM::SPRRegClass && "Expecting SPR register class!");
+ if (A == &ARM::DPR_8RegClass)
+ return A;
+ return &ARM::DPR_VFP2RegClass;
+ }
+
+ assert(A->getSize() == 16 && "Expecting a Q register class!");
+ if (B == &ARM::SPR_8RegClass)
+ return &ARM::QPR_8RegClass;
+ return &ARM::QPR_VFP2RegClass;
+ case 5:
+ case 6:
+ // D sub-registers.
+ if (B == &ARM::DPR_VFP2RegClass)
+ return &ARM::QPR_VFP2RegClass;
+ if (B == &ARM::DPR_8RegClass)
+ return &ARM::QPR_8RegClass;
+ return A;
+ }
+ return 0;
+}
+
+const TargetRegisterClass *
+ARMBaseRegisterInfo::getPointerRegClass(unsigned Kind) const {
+ return ARM::GPRRegisterClass;
}
/// getAllocationOrder - Returns the register allocation order for a specified
///
bool ARMBaseRegisterInfo::hasFP(const MachineFunction &MF) const {
const MachineFrameInfo *MFI = MF.getFrameInfo();
- return (NoFramePointerElim ||
+ return ((NoFramePointerElim && MFI->hasCalls())||
+ needsStackRealignment(MF) ||
MFI->hasVarSizedObjects() ||
MFI->isFrameAddressTaken());
}
-static unsigned estimateStackSize(MachineFunction &MF, MachineFrameInfo *MFI) {
+bool ARMBaseRegisterInfo::canRealignStack(const MachineFunction &MF) const {
+ const MachineFrameInfo *MFI = MF.getFrameInfo();
+ const ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+ return (RealignStack &&
+ !AFI->isThumb1OnlyFunction() &&
+ !MFI->hasVarSizedObjects());
+}
+
+bool ARMBaseRegisterInfo::
+needsStackRealignment(const MachineFunction &MF) const {
+ const MachineFrameInfo *MFI = MF.getFrameInfo();
+ const ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+ unsigned StackAlign = MF.getTarget().getFrameInfo()->getStackAlignment();
+ return (RealignStack &&
+ !AFI->isThumb1OnlyFunction() &&
+ (MFI->getMaxAlignment() > StackAlign) &&
+ !MFI->hasVarSizedObjects());
+}
+
+bool ARMBaseRegisterInfo::
+cannotEliminateFrame(const MachineFunction &MF) const {
+ const MachineFrameInfo *MFI = MF.getFrameInfo();
+ if (NoFramePointerElim && MFI->hasCalls())
+ return true;
+ return MFI->hasVarSizedObjects() || MFI->isFrameAddressTaken()
+ || needsStackRealignment(MF);
+}
+
+/// estimateStackSize - Estimate and return the size of the frame.
+static unsigned estimateStackSize(MachineFunction &MF) {
const MachineFrameInfo *FFI = MF.getFrameInfo();
int Offset = 0;
for (int i = FFI->getObjectIndexBegin(); i != 0; ++i) {
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 a 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;
+
+ if (AddrMode == ARMII::AddrMode6)
+ return 0;
+ break; // At most one FI per instruction
+ }
+ }
+ }
+
+ return Limit;
+}
+
void
ARMBaseRegisterInfo::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
- RegScavenger *RS) const {
+ RegScavenger *RS) const {
// 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
SmallVector<unsigned, 4> UnspilledCS2GPRs;
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+ // Spill R4 if Thumb2 function requires stack realignment - it will be used as
+ // scratch register.
+ // FIXME: It will be better just to find spare register here.
+ if (needsStackRealignment(MF) &&
+ AFI->isThumb2Function())
+ MF.getRegInfo().setPhysRegUsed(ARM::R4);
+
+ // Spill LR if Thumb1 function uses variable length argument lists.
+ if (AFI->isThumb1OnlyFunction() && AFI->getVarArgsRegSaveSize() > 0)
+ MF.getRegInfo().setPhysRegUsed(ARM::LR);
+
// 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.
const unsigned *CSRegs = getCalleeSavedRegs();
}
}
- if (CSRegClasses[i] == &ARM::GPRRegClass) {
+ if (CSRegClasses[i] == ARM::GPRRegisterClass ||
+ CSRegClasses[i] == ARM::tGPRRegisterClass) {
if (Spilled) {
NumGPRSpills++;
}
}
+ // If any of the stack slot references may be out of range of an immediate
+ // offset, make sure a register (or a spill slot) is available for the
+ // register scavenger. Note that if we're indexing off the frame pointer, the
+ // effective stack size is 4 bytes larger since the FP points to the stack
+ // slot of the previous FP.
+ bool BigStack = RS &&
+ estimateStackSize(MF) + (hasFP(MF) ? 4 : 0) >= estimateRSStackSizeLimit(MF);
+
bool ExtraCSSpill = false;
- if (!CanEliminateFrame || hasFP(MF)) {
+ if (BigStack || !CanEliminateFrame || cannotEliminateFrame(MF)) {
AFI->setHasStackFrame(true);
// If LR is not spilled, but at least one of R4, R5, R6, and R7 is spilled.
// Estimate if we might need to scavenge a register at some point in order
// to materialize a stack offset. If so, either spill one additional
// callee-saved register or reserve a special spill slot to facilitate
- // 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 any non-reserved CS register isn't spilled, just spill one or two
- // extra. That should take care of it!
- unsigned NumExtras = TargetAlign / 4;
- SmallVector<unsigned, 2> Extras;
- while (NumExtras && !UnspilledCS1GPRs.empty()) {
- unsigned Reg = UnspilledCS1GPRs.back();
- UnspilledCS1GPRs.pop_back();
- if (!isReservedReg(MF, Reg)) {
- Extras.push_back(Reg);
- NumExtras--;
- }
+ // register scavenging. Thumb1 needs a spill slot for stack pointer
+ // adjustments also, even when the frame itself is small.
+ if (BigStack && !ExtraCSSpill) {
+ // 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;
+ SmallVector<unsigned, 2> Extras;
+ while (NumExtras && !UnspilledCS1GPRs.empty()) {
+ unsigned Reg = UnspilledCS1GPRs.back();
+ UnspilledCS1GPRs.pop_back();
+ if (!isReservedReg(MF, Reg)) {
+ Extras.push_back(Reg);
+ NumExtras--;
}
+ }
+ // For non-Thumb1 functions, also check for hi-reg CS registers
+ if (!AFI->isThumb1OnlyFunction()) {
while (NumExtras && !UnspilledCS2GPRs.empty()) {
unsigned Reg = UnspilledCS2GPRs.back();
UnspilledCS2GPRs.pop_back();
NumExtras--;
}
}
- if (Extras.size() && NumExtras == 0) {
- for (unsigned i = 0, e = Extras.size(); i != e; ++i) {
- MF.getRegInfo().setPhysRegUsed(Extras[i]);
- AFI->setCSRegisterIsSpilled(Extras[i]);
- }
- } else {
- // Reserve a slot closest to SP or frame pointer.
- const TargetRegisterClass *RC = &ARM::GPRRegClass;
- RS->setScavengingFrameIndex(MFI->CreateStackObject(RC->getSize(),
- RC->getAlignment()));
+ }
+ if (Extras.size() && NumExtras == 0) {
+ for (unsigned i = 0, e = Extras.size(); i != e; ++i) {
+ MF.getRegInfo().setPhysRegUsed(Extras[i]);
+ AFI->setCSRegisterIsSpilled(Extras[i]);
}
+ } else if (!AFI->isThumb1OnlyFunction()) {
+ // note: Thumb1 functions spill to R12, not the stack. Reserve a slot
+ // closest to SP or frame pointer.
+ const TargetRegisterClass *RC = ARM::GPRRegisterClass;
+ MachineFrameInfo *MFI = MF.getFrameInfo();
+ RS->setScavengingFrameIndex(MFI->CreateStackObject(RC->getSize(),
+ RC->getAlignment(),
+ false));
}
}
}
return ARM::LR;
}
-unsigned ARMBaseRegisterInfo::getFrameRegister(MachineFunction &MF) const {
+unsigned
+ARMBaseRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
if (STI.isTargetDarwin() || hasFP(MF))
return FramePtr;
return ARM::SP;
}
+int
+ARMBaseRegisterInfo::getFrameIndexReference(const MachineFunction &MF, int FI,
+ unsigned &FrameReg) const {
+ const MachineFrameInfo *MFI = MF.getFrameInfo();
+ const ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+ int Offset = MFI->getObjectOffset(FI) + MFI->getStackSize();
+ bool isFixed = MFI->isFixedObjectIndex(FI);
+
+ FrameReg = ARM::SP;
+ if (AFI->isGPRCalleeSavedArea1Frame(FI))
+ Offset -= AFI->getGPRCalleeSavedArea1Offset();
+ else if (AFI->isGPRCalleeSavedArea2Frame(FI))
+ Offset -= AFI->getGPRCalleeSavedArea2Offset();
+ else if (AFI->isDPRCalleeSavedAreaFrame(FI))
+ Offset -= AFI->getDPRCalleeSavedAreaOffset();
+ else if (needsStackRealignment(MF)) {
+ // When dynamically realigning the stack, use the frame pointer for
+ // parameters, and the stack pointer for locals.
+ assert (hasFP(MF) && "dynamic stack realignment without a FP!");
+ if (isFixed) {
+ FrameReg = getFrameRegister(MF);
+ Offset -= AFI->getFramePtrSpillOffset();
+ }
+ } else if (hasFP(MF) && AFI->hasStackFrame()) {
+ if (isFixed || MFI->hasVarSizedObjects()) {
+ // Use frame pointer to reference fixed objects unless this is a
+ // frameless function.
+ FrameReg = getFrameRegister(MF);
+ Offset -= AFI->getFramePtrSpillOffset();
+ } else if (AFI->isThumb2Function()) {
+ // In Thumb2 mode, the negative offset is very limited.
+ int FPOffset = Offset - AFI->getFramePtrSpillOffset();
+ if (FPOffset >= -255 && FPOffset < 0) {
+ FrameReg = getFrameRegister(MF);
+ Offset = FPOffset;
+ }
+ }
+ }
+ return Offset;
+}
+
+
+int
+ARMBaseRegisterInfo::getFrameIndexOffset(const MachineFunction &MF,
+ int FI) const {
+ unsigned FrameReg;
+ return getFrameIndexReference(MF, FI, FrameReg);
+}
+
unsigned ARMBaseRegisterInfo::getEHExceptionRegister() const {
llvm_unreachable("What is the exception register");
return 0;
}
unsigned ARMBaseRegisterInfo::getRegisterPairEven(unsigned Reg,
- const MachineFunction &MF) const {
+ const MachineFunction &MF) const {
switch (Reg) {
default: break;
// Return 0 if either register of the pair is a special register.
case ARM::R1:
return ARM::R0;
case ARM::R3:
- // FIXME!
- return STI.isThumb1Only() ? 0 : ARM::R2;
+ return ARM::R2;
case ARM::R5:
return ARM::R4;
case ARM::R7:
case ARM::R0:
return ARM::R1;
case ARM::R2:
- // FIXME!
- return STI.isThumb1Only() ? 0 : ARM::R3;
+ return ARM::R3;
case ARM::R4:
return ARM::R5;
case ARM::R6:
return 0;
}
-// FIXME: Dup in ARMBaseInstrInfo.cpp
-static inline
-const MachineInstrBuilder &AddDefaultPred(const MachineInstrBuilder &MIB) {
- return MIB.addImm((int64_t)ARMCC::AL).addReg(0);
-}
-
-static inline
-const MachineInstrBuilder &AddDefaultCC(const MachineInstrBuilder &MIB) {
- return MIB.addReg(0);
-}
-
/// emitLoadConstPool - Emits a load from constpool to materialize the
/// specified immediate.
void ARMBaseRegisterInfo::
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))
return true;
}
+bool ARMBaseRegisterInfo::
+requiresFrameIndexScavenging(const MachineFunction &MF) const {
+ return true;
+}
+
// hasReservedCallFrame - Under normal circumstances, when a frame pointer is
// not required, we reserve argument space for call sites in the function
// immediately on entry to the current function. This eliminates the need for
return !MF.getFrameInfo()->hasVarSizedObjects();
}
-/// emitARMRegPlusImmediate - Emits a series of instructions to materialize
-/// a destreg = basereg + immediate in ARM code.
-static
-void emitARMRegPlusImmediate(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator &MBBI,
- unsigned DestReg, unsigned BaseReg, int NumBytes,
- ARMCC::CondCodes Pred, unsigned PredReg,
- const ARMBaseInstrInfo &TII,
- DebugLoc dl) {
- bool isSub = NumBytes < 0;
- if (isSub) NumBytes = -NumBytes;
-
- while (NumBytes) {
- unsigned RotAmt = ARM_AM::getSOImmValRotate(NumBytes);
- unsigned ThisVal = NumBytes & ARM_AM::rotr32(0xFF, RotAmt);
- assert(ThisVal && "Didn't extract field correctly");
-
- // We will handle these bits from offset, clear them.
- NumBytes &= ~ThisVal;
-
- assert(ARM_AM::getSOImmVal(ThisVal) != -1 && "Bit extraction didn't work?");
-
- // Build the new ADD / SUB.
- unsigned Opc = TII.getOpcode(isSub ? ARMII::SUBri : ARMII::ADDri);
- BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
- .addReg(BaseReg, RegState::Kill).addImm(ThisVal)
- .addImm((unsigned)Pred).addReg(PredReg).addReg(0);
- BaseReg = DestReg;
- }
+// canSimplifyCallFramePseudos - If there is a reserved call frame, the
+// call frame pseudos can be simplified. Unlike most targets, having a FP
+// is not sufficient here since we still may reference some objects via SP
+// even when FP is available in Thumb2 mode.
+bool ARMBaseRegisterInfo::
+canSimplifyCallFramePseudos(MachineFunction &MF) const {
+ return hasReservedCallFrame(MF) || MF.getFrameInfo()->hasVarSizedObjects();
}
static void
-emitSPUpdate(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI,
- const ARMBaseInstrInfo &TII, DebugLoc dl,
+emitSPUpdate(bool isARM,
+ MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI,
+ DebugLoc dl, const ARMBaseInstrInfo &TII,
int NumBytes,
ARMCC::CondCodes Pred = ARMCC::AL, unsigned PredReg = 0) {
- emitARMRegPlusImmediate(MBB, MBBI, ARM::SP, ARM::SP, NumBytes,
- Pred, PredReg, TII, dl);
+ if (isARM)
+ emitARMRegPlusImmediate(MBB, MBBI, dl, ARM::SP, ARM::SP, NumBytes,
+ Pred, PredReg, TII);
+ else
+ emitT2RegPlusImmediate(MBB, MBBI, dl, ARM::SP, ARM::SP, NumBytes,
+ Pred, PredReg, TII);
}
+
void ARMBaseRegisterInfo::
eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) const {
unsigned Align = MF.getTarget().getFrameInfo()->getStackAlignment();
Amount = (Amount+Align-1)/Align*Align;
+ ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+ assert(!AFI->isThumb1OnlyFunction() &&
+ "This eliminateCallFramePseudoInstr does not support Thumb1!");
+ bool isARM = !AFI->isThumbFunction();
+
// Replace the pseudo instruction with a new instruction...
unsigned Opc = Old->getOpcode();
- ARMCC::CondCodes Pred = (ARMCC::CondCodes)Old->getOperand(1).getImm();
+ int PIdx = Old->findFirstPredOperandIdx();
+ ARMCC::CondCodes Pred = (PIdx == -1)
+ ? ARMCC::AL : (ARMCC::CondCodes)Old->getOperand(PIdx).getImm();
if (Opc == ARM::ADJCALLSTACKDOWN || Opc == ARM::tADJCALLSTACKDOWN) {
// Note: PredReg is operand 2 for ADJCALLSTACKDOWN.
unsigned PredReg = Old->getOperand(2).getReg();
- emitSPUpdate(MBB, I, TII, dl, -Amount, Pred, PredReg);
+ emitSPUpdate(isARM, MBB, I, dl, TII, -Amount, Pred, PredReg);
} else {
// Note: PredReg is operand 3 for ADJCALLSTACKUP.
unsigned PredReg = Old->getOperand(3).getReg();
assert(Opc == ARM::ADJCALLSTACKUP || Opc == ARM::tADJCALLSTACKUP);
- emitSPUpdate(MBB, I, TII, dl, Amount, Pred, PredReg);
+ emitSPUpdate(isARM, MBB, I, dl, TII, Amount, Pred, PredReg);
}
}
}
MBB.erase(I);
}
-/// findScratchRegister - Find a 'free' ARM register. If register scavenger
-/// is not being used, R12 is available. Otherwise, try for a call-clobbered
-/// register first and then a spilled callee-saved register if that fails.
-static
-unsigned findScratchRegister(RegScavenger *RS, const TargetRegisterClass *RC,
- ARMFunctionInfo *AFI) {
- unsigned Reg = RS ? RS->FindUnusedReg(RC, true) : (unsigned) ARM::R12;
- assert (!AFI->isThumb1OnlyFunction());
- if (Reg == 0)
- // Try a already spilled CS register.
- Reg = RS->FindUnusedReg(RC, AFI->getSpilledCSRegisters());
-
- return Reg;
-}
-
-int ARMBaseRegisterInfo::
-rewriteFrameIndex(MachineInstr &MI, unsigned FrameRegIdx,
- unsigned FrameReg, int Offset) const
-{
- unsigned Opcode = MI.getOpcode();
- const TargetInstrDesc &Desc = MI.getDesc();
- unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
- bool isSub = false;
-
- // Memory operands in inline assembly always use AddrMode2.
- if (Opcode == ARM::INLINEASM)
- AddrMode = ARMII::AddrMode2;
-
- if (Opcode == getOpcode(ARMII::ADDri)) {
- Offset += MI.getOperand(FrameRegIdx+1).getImm();
- if (Offset == 0) {
- // Turn it into a move.
- MI.setDesc(TII.get(getOpcode(ARMII::MOVr)));
- MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
- MI.RemoveOperand(FrameRegIdx+1);
- return 0;
- } else if (Offset < 0) {
- Offset = -Offset;
- isSub = true;
- MI.setDesc(TII.get(getOpcode(ARMII::SUBri)));
- }
-
- // Common case: small offset, fits into instruction.
- if (ARM_AM::getSOImmVal(Offset) != -1) {
- // Replace the FrameIndex with sp / fp
- MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
- MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
- return 0;
- }
-
- // Otherwise, pull as much of the immedidate into this ADDri/SUBri
- // as possible.
- unsigned RotAmt = ARM_AM::getSOImmValRotate(Offset);
- unsigned ThisImmVal = Offset & ARM_AM::rotr32(0xFF, RotAmt);
-
- // We will handle these bits from offset, clear them.
- Offset &= ~ThisImmVal;
-
- // Get the properly encoded SOImmVal field.
- assert(ARM_AM::getSOImmVal(ThisImmVal) != -1 &&
- "Bit extraction didn't work?");
- MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal);
- } else {
- unsigned ImmIdx = 0;
- int InstrOffs = 0;
- unsigned NumBits = 0;
- unsigned Scale = 1;
- switch (AddrMode) {
- case ARMII::AddrMode2: {
- ImmIdx = FrameRegIdx+2;
- InstrOffs = ARM_AM::getAM2Offset(MI.getOperand(ImmIdx).getImm());
- if (ARM_AM::getAM2Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub)
- InstrOffs *= -1;
- NumBits = 12;
- break;
- }
- case ARMII::AddrMode3: {
- ImmIdx = FrameRegIdx+2;
- InstrOffs = ARM_AM::getAM3Offset(MI.getOperand(ImmIdx).getImm());
- if (ARM_AM::getAM3Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub)
- InstrOffs *= -1;
- NumBits = 8;
- break;
- }
- case ARMII::AddrMode5: {
- ImmIdx = FrameRegIdx+1;
- InstrOffs = ARM_AM::getAM5Offset(MI.getOperand(ImmIdx).getImm());
- if (ARM_AM::getAM5Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub)
- InstrOffs *= -1;
- NumBits = 8;
- Scale = 4;
- break;
- }
- default:
- llvm_unreachable("Unsupported addressing mode!");
- break;
- }
-
- Offset += InstrOffs * Scale;
- assert((Offset & (Scale-1)) == 0 && "Can't encode this offset!");
- if (Offset < 0) {
- Offset = -Offset;
- isSub = true;
- }
-
- // Attempt to fold address comp. if opcode has offset bits
- if (NumBits > 0) {
- // Common case: small offset, fits into instruction.
- MachineOperand &ImmOp = MI.getOperand(ImmIdx);
- int ImmedOffset = Offset / Scale;
- unsigned Mask = (1 << NumBits) - 1;
- if ((unsigned)Offset <= Mask * Scale) {
- // Replace the FrameIndex with sp
- MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
- if (isSub)
- ImmedOffset |= 1 << NumBits;
- ImmOp.ChangeToImmediate(ImmedOffset);
- return 0;
- }
-
- // Otherwise, it didn't fit. Pull in what we can to simplify the immed.
- ImmedOffset = ImmedOffset & Mask;
- if (isSub)
- ImmedOffset |= 1 << NumBits;
- ImmOp.ChangeToImmediate(ImmedOffset);
- Offset &= ~(Mask*Scale);
- }
- }
-
- return (isSub) ? -Offset : Offset;
-}
-
-void ARMBaseRegisterInfo::
-eliminateFrameIndex(MachineBasicBlock::iterator II,
- int SPAdj, RegScavenger *RS) const {
+unsigned
+ARMBaseRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
+ int SPAdj, FrameIndexValue *Value,
+ RegScavenger *RS) const {
unsigned i = 0;
MachineInstr &MI = *II;
MachineBasicBlock &MBB = *MI.getParent();
MachineFunction &MF = *MBB.getParent();
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
- DebugLoc dl = MI.getDebugLoc();
+ assert(!AFI->isThumb1OnlyFunction() &&
+ "This eliminateFrameIndex does not support Thumb1!");
while (!MI.getOperand(i).isFI()) {
++i;
assert(i < MI.getNumOperands() && "Instr doesn't have FrameIndex operand!");
}
- unsigned FrameReg = ARM::SP;
int FrameIndex = MI.getOperand(i).getIndex();
- int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex) +
- MF.getFrameInfo()->getStackSize() + SPAdj;
-
- if (AFI->isGPRCalleeSavedArea1Frame(FrameIndex))
- Offset -= AFI->getGPRCalleeSavedArea1Offset();
- else if (AFI->isGPRCalleeSavedArea2Frame(FrameIndex))
- 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.
- FrameReg = getFrameRegister(MF);
- Offset -= AFI->getFramePtrSpillOffset();
+ unsigned FrameReg;
+
+ int Offset = getFrameIndexReference(MF, FrameIndex, FrameReg);
+ if (FrameReg != ARM::SP)
+ SPAdj = 0;
+ Offset += SPAdj;
+
+ // Modify MI as necessary to handle as much of 'Offset' as possible
+ bool Done = false;
+ if (!AFI->isThumbFunction())
+ Done = rewriteARMFrameIndex(MI, i, FrameReg, Offset, TII);
+ else {
+ assert(AFI->isThumb2Function());
+ Done = rewriteT2FrameIndex(MI, i, FrameReg, Offset, TII);
}
-
- // modify MI as necessary to handle as much of 'Offset' as possible
- Offset = rewriteFrameIndex(MI, i, FrameReg, Offset);
- if (Offset == 0)
- return;
+ if (Done)
+ return 0;
// 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!");
-
- // 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);
- if (ScratchReg == 0)
- // No register is "free". Scavenge a register.
- ScratchReg = RS->scavengeRegister(&ARM::GPRRegClass, II, SPAdj);
+ assert((Offset ||
+ (MI.getDesc().TSFlags & ARMII::AddrModeMask) == ARMII::AddrMode4 ||
+ (MI.getDesc().TSFlags & ARMII::AddrModeMask) == ARMII::AddrMode6) &&
+ "This code isn't needed if offset already handled!");
+
+ unsigned ScratchReg = 0;
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();
- emitARMRegPlusImmediate(MBB, II, ScratchReg, FrameReg,
- Offset, Pred, PredReg, TII, dl);
- MI.getOperand(i).ChangeToRegister(ScratchReg, false, false, true);
+ if (Offset == 0)
+ // Must be addrmode4/6.
+ MI.getOperand(i).ChangeToRegister(FrameReg, false, false, false);
+ else {
+ ScratchReg = MF.getRegInfo().createVirtualRegister(ARM::GPRRegisterClass);
+ if (Value) {
+ Value->first = FrameReg; // use the frame register as a kind indicator
+ Value->second = Offset;
+ }
+ 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);
+ if (!ReuseFrameIndexVals)
+ ScratchReg = 0;
+ }
+ return ScratchReg;
}
-/// Move iterator pass the next bunch of callee save load / store ops for
+/// Move iterator past the next bunch of callee save load / store ops for
/// the particular spill area (1: integer area 1, 2: integer area 2,
/// 3: fp area, 0: don't care).
static void movePastCSLoadStoreOps(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MBBI = MBB.begin();
MachineFrameInfo *MFI = MF.getFrameInfo();
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+ assert(!AFI->isThumb1OnlyFunction() &&
+ "This emitPrologue does not support Thumb1!");
+ bool isARM = !AFI->isThumbFunction();
unsigned VARegSaveSize = AFI->getVarArgsRegSaveSize();
unsigned NumBytes = MFI->getStackSize();
const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
unsigned GPRCS1Size = 0, GPRCS2Size = 0, DPRCSSize = 0;
int FramePtrSpillFI = 0;
+ // Allocate the vararg register save area. This is not counted in NumBytes.
if (VARegSaveSize)
- emitSPUpdate(MBB, MBBI, TII, dl, -VARegSaveSize);
+ emitSPUpdate(isARM, MBB, MBBI, dl, TII, -VARegSaveSize);
if (!AFI->hasStackFrame()) {
if (NumBytes != 0)
- emitSPUpdate(MBB, MBBI, TII, dl, -NumBytes);
+ emitSPUpdate(isARM, MBB, MBBI, dl, TII, -NumBytes);
return;
}
}
// Build the new SUBri to adjust SP for integer callee-save spill area 1.
- emitSPUpdate(MBB, MBBI, TII, dl, -GPRCS1Size);
- movePastCSLoadStoreOps(MBB, MBBI, getOpcode(ARMII::STRrr),
- getOpcode(ARMII::STRri), 1, STI);
-
- // Darwin ABI requires FP to point to the stack slot that contains the
- // previous FP.
+ emitSPUpdate(isARM, MBB, MBBI, dl, TII, -GPRCS1Size);
+ movePastCSLoadStoreOps(MBB, MBBI, ARM::STR, ARM::t2STRi12, 1, STI);
+
+ // Set FP to point to the stack slot that contains the previous FP.
+ // For Darwin, FP is R7, which has now been stored in spill area 1.
+ // Otherwise, if this is not Darwin, all the callee-saved registers go
+ // into spill area 1, including the FP in R11. In either case, it is
+ // now safe to emit this assignment.
if (STI.isTargetDarwin() || hasFP(MF)) {
+ unsigned ADDriOpc = !AFI->isThumbFunction() ? ARM::ADDri : ARM::t2ADDri;
MachineInstrBuilder MIB =
- BuildMI(MBB, MBBI, dl, TII.get(getOpcode(ARMII::ADDri)), FramePtr)
+ BuildMI(MBB, MBBI, dl, TII.get(ADDriOpc), FramePtr)
.addFrameIndex(FramePtrSpillFI).addImm(0);
AddDefaultCC(AddDefaultPred(MIB));
}
// Build the new SUBri to adjust SP for integer callee-save spill area 2.
- emitSPUpdate(MBB, MBBI, TII, dl, -GPRCS2Size);
+ emitSPUpdate(isARM, MBB, MBBI, dl, TII, -GPRCS2Size);
// Build the new SUBri to adjust SP for FP callee-save spill area.
- movePastCSLoadStoreOps(MBB, MBBI, getOpcode(ARMII::STRrr),
- getOpcode(ARMII::STRri), 2, STI);
- emitSPUpdate(MBB, MBBI, TII, dl, -DPRCSSize);
+ movePastCSLoadStoreOps(MBB, MBBI, ARM::STR, ARM::t2STRi12, 2, STI);
+ emitSPUpdate(isARM, MBB, MBBI, dl, TII, -DPRCSSize);
// Determine starting offsets of spill areas.
unsigned DPRCSOffset = NumBytes - (GPRCS1Size + GPRCS2Size + DPRCSSize);
unsigned GPRCS2Offset = DPRCSOffset + DPRCSSize;
unsigned GPRCS1Offset = GPRCS2Offset + GPRCS2Size;
- AFI->setFramePtrSpillOffset(MFI->getObjectOffset(FramePtrSpillFI) + NumBytes);
+ if (STI.isTargetDarwin() || hasFP(MF))
+ AFI->setFramePtrSpillOffset(MFI->getObjectOffset(FramePtrSpillFI) +
+ NumBytes);
AFI->setGPRCalleeSavedArea1Offset(GPRCS1Offset);
AFI->setGPRCalleeSavedArea2Offset(GPRCS2Offset);
AFI->setDPRCalleeSavedAreaOffset(DPRCSOffset);
+ movePastCSLoadStoreOps(MBB, MBBI, ARM::VSTRD, 0, 3, STI);
NumBytes = DPRCSOffset;
if (NumBytes) {
- // Insert it after all the callee-save spills.
- movePastCSLoadStoreOps(MBB, MBBI, ARM::FSTD, 0, 3, STI);
- emitSPUpdate(MBB, MBBI, TII, dl, -NumBytes);
+ // Adjust SP after all the callee-save spills.
+ emitSPUpdate(isARM, MBB, MBBI, dl, TII, -NumBytes);
}
if (STI.isTargetELF() && hasFP(MF)) {
AFI->setGPRCalleeSavedArea1Size(GPRCS1Size);
AFI->setGPRCalleeSavedArea2Size(GPRCS2Size);
AFI->setDPRCalleeSavedAreaSize(DPRCSSize);
+
+ // If we need dynamic stack realignment, do it here.
+ if (needsStackRealignment(MF)) {
+ unsigned MaxAlign = MFI->getMaxAlignment();
+ assert (!AFI->isThumb1OnlyFunction());
+ if (!AFI->isThumbFunction()) {
+ // Emit bic sp, sp, MaxAlign
+ AddDefaultCC(AddDefaultPred(BuildMI(MBB, MBBI, dl,
+ TII.get(ARM::BICri), ARM::SP)
+ .addReg(ARM::SP, RegState::Kill)
+ .addImm(MaxAlign-1)));
+ } else {
+ // We cannot use sp as source/dest register here, thus we're emitting the
+ // following sequence:
+ // mov r4, sp
+ // bic r4, r4, MaxAlign
+ // mov sp, r4
+ // FIXME: It will be better just to find spare register here.
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVgpr2tgpr), ARM::R4)
+ .addReg(ARM::SP, RegState::Kill);
+ AddDefaultCC(AddDefaultPred(BuildMI(MBB, MBBI, dl,
+ TII.get(ARM::t2BICri), ARM::R4)
+ .addReg(ARM::R4, RegState::Kill)
+ .addImm(MaxAlign-1)));
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVtgpr2gpr), ARM::SP)
+ .addReg(ARM::R4, RegState::Kill);
+ }
+ }
}
static bool isCalleeSavedRegister(unsigned Reg, const unsigned *CSRegs) {
}
static bool isCSRestore(MachineInstr *MI,
- const ARMBaseInstrInfo &TII,
+ const ARMBaseInstrInfo &TII,
const unsigned *CSRegs) {
- return ((MI->getOpcode() == (int)ARM::FLDD ||
- MI->getOpcode() == (int)TII.getOpcode(ARMII::LDRrr) ||
- MI->getOpcode() == (int)TII.getOpcode(ARMII::LDRri)) &&
+ return ((MI->getOpcode() == (int)ARM::VLDRD ||
+ MI->getOpcode() == (int)ARM::LDR ||
+ MI->getOpcode() == (int)ARM::t2LDRi12) &&
MI->getOperand(1).isFI() &&
isCalleeSavedRegister(MI->getOperand(0).getReg(), CSRegs));
}
void ARMBaseRegisterInfo::
-emitEpilogue(MachineFunction &MF,
- MachineBasicBlock &MBB) const {
+emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const {
MachineBasicBlock::iterator MBBI = prior(MBB.end());
- assert(MBBI->getOpcode() == (int)getOpcode(ARMII::BX_RET) &&
+ assert(MBBI->getDesc().isReturn() &&
"Can only insert epilog into returning blocks");
DebugLoc dl = MBBI->getDebugLoc();
MachineFrameInfo *MFI = MF.getFrameInfo();
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+ assert(!AFI->isThumb1OnlyFunction() &&
+ "This emitEpilogue does not support Thumb1!");
+ bool isARM = !AFI->isThumbFunction();
+
unsigned VARegSaveSize = AFI->getVarArgsRegSaveSize();
int NumBytes = (int)MFI->getStackSize();
if (!AFI->hasStackFrame()) {
if (NumBytes != 0)
- emitSPUpdate(MBB, MBBI, TII, dl, NumBytes);
+ emitSPUpdate(isARM, MBB, MBBI, dl, TII, NumBytes);
} else {
- // Unwind MBBI to point to first LDR / FLDD.
+ // Unwind MBBI to point to first LDR / VLDRD.
const unsigned *CSRegs = getCalleeSavedRegs();
if (MBBI != MBB.begin()) {
do
// 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)) {
- if (NumBytes)
- BuildMI(MBB, MBBI, dl, TII.get(getOpcode(ARMII::SUBri)), ARM::SP)
- .addReg(FramePtr)
- .addImm(NumBytes)
- .addImm((unsigned)ARMCC::AL).addReg(0).addReg(0);
- else
- BuildMI(MBB, MBBI, dl, TII.get(getOpcode(ARMII::MOVr)), ARM::SP)
- .addReg(FramePtr)
- .addImm((unsigned)ARMCC::AL).addReg(0).addReg(0);
+ AFI->getDPRCalleeSavedAreaOffset()) {
+ if (NumBytes) {
+ 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.
+ 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) {
- emitSPUpdate(MBB, MBBI, TII, dl, NumBytes);
- }
+ } else if (NumBytes)
+ emitSPUpdate(isARM, MBB, MBBI, dl, TII, NumBytes);
// Move SP to start of integer callee save spill area 2.
- movePastCSLoadStoreOps(MBB, MBBI, ARM::FLDD, 0, 3, STI);
- emitSPUpdate(MBB, MBBI, TII, dl, AFI->getDPRCalleeSavedAreaSize());
+ movePastCSLoadStoreOps(MBB, MBBI, ARM::VLDRD, 0, 3, STI);
+ emitSPUpdate(isARM, MBB, MBBI, dl, TII, AFI->getDPRCalleeSavedAreaSize());
// Move SP to start of integer callee save spill area 1.
- movePastCSLoadStoreOps(MBB, MBBI, getOpcode(ARMII::LDRrr),
- getOpcode(ARMII::LDRri), 2, STI);
- emitSPUpdate(MBB, MBBI, TII, dl, AFI->getGPRCalleeSavedArea2Size());
+ movePastCSLoadStoreOps(MBB, MBBI, ARM::LDR, ARM::t2LDRi12, 2, STI);
+ emitSPUpdate(isARM, MBB, MBBI, dl, TII, AFI->getGPRCalleeSavedArea2Size());
// Move SP to SP upon entry to the function.
- movePastCSLoadStoreOps(MBB, MBBI, getOpcode(ARMII::LDRrr),
- getOpcode(ARMII::LDRri), 1, STI);
- emitSPUpdate(MBB, MBBI, TII, dl, AFI->getGPRCalleeSavedArea1Size());
+ movePastCSLoadStoreOps(MBB, MBBI, ARM::LDR, ARM::t2LDRi12, 1, STI);
+ emitSPUpdate(isARM, MBB, MBBI, dl, TII, AFI->getGPRCalleeSavedArea1Size());
}
if (VARegSaveSize)
- emitSPUpdate(MBB, MBBI, TII, dl, VARegSaveSize);
-
+ emitSPUpdate(isARM, MBB, MBBI, dl, TII, VARegSaveSize);
}
#include "ARMGenRegisterInfo.inc"