#include "ARMAddressingModes.h"
#include "ARMBaseInstrInfo.h"
#include "ARMBaseRegisterInfo.h"
+#include "ARMFrameInfo.h"
#include "ARMInstrInfo.h"
#include "ARMMachineFunctionInfo.h"
#include "ARMSubtarget.h"
#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"
-using namespace llvm;
+#include "llvm/Support/CommandLine.h"
-unsigned ARMBaseRegisterInfo::getRegisterNumbering(unsigned RegEnum,
- bool *isSPVFP) {
- if (isSPVFP)
- *isSPVFP = false;
+using namespace llvm;
- using namespace ARM;
- switch (RegEnum) {
- default:
- llvm_unreachable("Unknown ARM register!");
- case R0: case D0: case Q0: return 0;
- case R1: case D1: case Q1: return 1;
- case R2: case D2: case Q2: return 2;
- case R3: case D3: case Q3: return 3;
- case R4: case D4: case Q4: return 4;
- case R5: case D5: case Q5: return 5;
- case R6: case D6: case Q6: return 6;
- case R7: case D7: case Q7: return 7;
- case R8: case D8: case Q8: return 8;
- case R9: case D9: case Q9: return 9;
- case R10: case D10: case Q10: return 10;
- case R11: case D11: case Q11: return 11;
- case R12: case D12: case Q12: return 12;
- case SP: case D13: case Q13: return 13;
- case LR: case D14: case Q14: return 14;
- case PC: case D15: case Q15: return 15;
-
- case D16: return 16;
- case D17: return 17;
- case D18: return 18;
- case D19: return 19;
- case D20: return 20;
- case D21: return 21;
- case D22: return 22;
- case D23: return 23;
- case D24: return 24;
- case D25: return 25;
- case D26: return 27;
- case D27: return 27;
- case D28: return 28;
- case D29: return 29;
- case D30: return 30;
- case D31: return 31;
-
- case S0: case S1: case S2: case S3:
- case S4: case S5: case S6: case S7:
- case S8: case S9: case S10: case S11:
- case S12: case S13: case S14: case S15:
- case S16: case S17: case S18: case S19:
- case S20: case S21: case S22: case S23:
- case S24: case S25: case S26: case S27:
- case S28: case S29: case S30: case S31: {
- if (isSPVFP)
- *isSPVFP = true;
- switch (RegEnum) {
- default: return 0; // Avoid compile time warning.
- case S0: return 0;
- case S1: return 1;
- case S2: return 2;
- case S3: return 3;
- case S4: return 4;
- case S5: return 5;
- case S6: return 6;
- case S7: return 7;
- case S8: return 8;
- case S9: return 9;
- case S10: return 10;
- case S11: return 11;
- case S12: return 12;
- case S13: return 13;
- case S14: return 14;
- case S15: return 15;
- case S16: return 16;
- case S17: return 17;
- case S18: return 18;
- case S19: return 19;
- case S20: return 20;
- case S21: return 21;
- case S22: return 22;
- case S23: return 23;
- case S24: return 24;
- case S25: return 25;
- case S26: return 26;
- case S27: return 27;
- case S28: return 28;
- case S29: return 29;
- case S30: return 30;
- case S31: return 31;
- }
- }
- }
-}
+static cl::opt<bool>
+ForceAllBaseRegAlloc("arm-force-base-reg-alloc", cl::Hidden, cl::init(false),
+ cl::desc("Force use of virtual base registers for stack load/store"));
+static cl::opt<bool>
+EnableLocalStackAlloc("enable-local-stack-alloc", cl::init(true), cl::Hidden,
+ cl::desc("Enable pre-regalloc stack frame index allocation"));
+static cl::opt<bool>
+EnableBasePointer("arm-use-base-pointer", cl::Hidden, cl::init(true),
+ cl::desc("Enable use of a base pointer for complex stack frames"));
ARMBaseRegisterInfo::ARMBaseRegisterInfo(const ARMBaseInstrInfo &tii,
const ARMSubtarget &sti)
: ARMGenRegisterInfo(ARM::ADJCALLSTACKDOWN, ARM::ADJCALLSTACKUP),
TII(tii), STI(sti),
- FramePtr((STI.isTargetDarwin() || STI.isThumb()) ? ARM::R7 : ARM::R11) {
+ FramePtr((STI.isTargetDarwin() || STI.isThumb()) ? ARM::R7 : ARM::R11),
+ BasePtr(ARM::R6) {
}
const unsigned*
return STI.isTargetDarwin() ? DarwinCalleeSavedRegs : CalleeSavedRegs;
}
-const TargetRegisterClass* const *
-ARMBaseRegisterInfo::getCalleeSavedRegClasses(const MachineFunction *MF) const {
- static const TargetRegisterClass * const CalleeSavedRegClasses[] = {
- &ARM::GPRRegClass, &ARM::GPRRegClass, &ARM::GPRRegClass,
- &ARM::GPRRegClass, &ARM::GPRRegClass, &ARM::GPRRegClass,
- &ARM::GPRRegClass, &ARM::GPRRegClass, &ARM::GPRRegClass,
-
- &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass,
- &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass,
- 0
- };
-
- static const TargetRegisterClass * const ThumbCalleeSavedRegClasses[] = {
- &ARM::GPRRegClass, &ARM::GPRRegClass, &ARM::GPRRegClass,
- &ARM::GPRRegClass, &ARM::GPRRegClass, &ARM::tGPRRegClass,
- &ARM::tGPRRegClass,&ARM::tGPRRegClass,&ARM::tGPRRegClass,
-
- &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass,
- &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass,
- 0
- };
-
- static const TargetRegisterClass * const DarwinCalleeSavedRegClasses[] = {
- &ARM::GPRRegClass, &ARM::GPRRegClass, &ARM::GPRRegClass,
- &ARM::GPRRegClass, &ARM::GPRRegClass, &ARM::GPRRegClass,
- &ARM::GPRRegClass, &ARM::GPRRegClass,
-
- &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass,
- &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass,
- 0
- };
-
- static const TargetRegisterClass * const DarwinThumbCalleeSavedRegClasses[] ={
- &ARM::GPRRegClass, &ARM::tGPRRegClass, &ARM::tGPRRegClass,
- &ARM::tGPRRegClass, &ARM::tGPRRegClass, &ARM::GPRRegClass,
- &ARM::GPRRegClass, &ARM::GPRRegClass,
-
- &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass,
- &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass, &ARM::DPRRegClass,
- 0
- };
-
- if (STI.isThumb1Only()) {
- return STI.isTargetDarwin()
- ? DarwinThumbCalleeSavedRegClasses : ThumbCalleeSavedRegClasses;
- }
- return STI.isTargetDarwin()
- ? DarwinCalleeSavedRegClasses : CalleeSavedRegClasses;
-}
+BitVector ARMBaseRegisterInfo::
+getReservedRegs(const MachineFunction &MF) const {
+ const TargetFrameInfo *TFI = MF.getTarget().getFrameInfo();
-BitVector ARMBaseRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
// FIXME: avoid re-calculating this everytime.
BitVector Reserved(getNumRegs());
Reserved.set(ARM::SP);
Reserved.set(ARM::PC);
- if (STI.isTargetDarwin() || hasFP(MF))
+ Reserved.set(ARM::FPSCR);
+ if (TFI->hasFP(MF))
Reserved.set(FramePtr);
+ if (hasBasePointer(MF))
+ Reserved.set(BasePtr);
// Some targets reserve R9.
if (STI.isR9Reserved())
Reserved.set(ARM::R9);
bool ARMBaseRegisterInfo::isReservedReg(const MachineFunction &MF,
unsigned Reg) const {
+ const TargetFrameInfo *TFI = MF.getTarget().getFrameInfo();
+
switch (Reg) {
default: break;
case ARM::SP:
case ARM::PC:
return true;
+ case ARM::R6:
+ if (hasBasePointer(MF))
+ return true;
+ break;
case ARM::R7:
case ARM::R11:
- if (FramePtr == Reg && (STI.isTargetDarwin() || hasFP(MF)))
+ if (FramePtr == Reg && TFI->hasFP(MF))
return true;
break;
case ARM::R9:
return false;
}
+const TargetRegisterClass *
+ARMBaseRegisterInfo::getMatchingSuperRegClass(const TargetRegisterClass *A,
+ const TargetRegisterClass *B,
+ unsigned SubIdx) const {
+ switch (SubIdx) {
+ default: return 0;
+ case ARM::ssub_0:
+ case ARM::ssub_1:
+ case ARM::ssub_2:
+ case ARM::ssub_3: {
+ // 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;
+ }
+
+ if (A->getSize() == 16) {
+ if (B == &ARM::SPR_8RegClass)
+ return &ARM::QPR_8RegClass;
+ return &ARM::QPR_VFP2RegClass;
+ }
+
+ if (A->getSize() == 32) {
+ if (B == &ARM::SPR_8RegClass)
+ return 0; // Do not allow coalescing!
+ return &ARM::QQPR_VFP2RegClass;
+ }
+
+ assert(A->getSize() == 64 && "Expecting a QQQQ register class!");
+ return 0; // Do not allow coalescing!
+ }
+ case ARM::dsub_0:
+ case ARM::dsub_1:
+ case ARM::dsub_2:
+ case ARM::dsub_3: {
+ // D sub-registers.
+ if (A->getSize() == 16) {
+ if (B == &ARM::DPR_VFP2RegClass)
+ return &ARM::QPR_VFP2RegClass;
+ if (B == &ARM::DPR_8RegClass)
+ return 0; // Do not allow coalescing!
+ return A;
+ }
+
+ if (A->getSize() == 32) {
+ if (B == &ARM::DPR_VFP2RegClass)
+ return &ARM::QQPR_VFP2RegClass;
+ if (B == &ARM::DPR_8RegClass)
+ return 0; // Do not allow coalescing!
+ return A;
+ }
+
+ assert(A->getSize() == 64 && "Expecting a QQQQ register class!");
+ if (B != &ARM::DPRRegClass)
+ return 0; // Do not allow coalescing!
+ return A;
+ }
+ case ARM::dsub_4:
+ case ARM::dsub_5:
+ case ARM::dsub_6:
+ case ARM::dsub_7: {
+ // D sub-registers of QQQQ registers.
+ if (A->getSize() == 64 && B == &ARM::DPRRegClass)
+ return A;
+ return 0; // Do not allow coalescing!
+ }
+
+ case ARM::qsub_0:
+ case ARM::qsub_1: {
+ // Q sub-registers.
+ if (A->getSize() == 32) {
+ if (B == &ARM::QPR_VFP2RegClass)
+ return &ARM::QQPR_VFP2RegClass;
+ if (B == &ARM::QPR_8RegClass)
+ return 0; // Do not allow coalescing!
+ return A;
+ }
+
+ assert(A->getSize() == 64 && "Expecting a QQQQ register class!");
+ if (B == &ARM::QPRRegClass)
+ return A;
+ return 0; // Do not allow coalescing!
+ }
+ case ARM::qsub_2:
+ case ARM::qsub_3: {
+ // Q sub-registers of QQQQ registers.
+ if (A->getSize() == 64 && B == &ARM::QPRRegClass)
+ return A;
+ return 0; // Do not allow coalescing!
+ }
+ }
+ return 0;
+}
+
+bool
+ARMBaseRegisterInfo::canCombineSubRegIndices(const TargetRegisterClass *RC,
+ SmallVectorImpl<unsigned> &SubIndices,
+ unsigned &NewSubIdx) const {
+
+ unsigned Size = RC->getSize() * 8;
+ if (Size < 6)
+ return 0;
+
+ NewSubIdx = 0; // Whole register.
+ unsigned NumRegs = SubIndices.size();
+ if (NumRegs == 8) {
+ // 8 D registers -> 1 QQQQ register.
+ return (Size == 512 &&
+ SubIndices[0] == ARM::dsub_0 &&
+ SubIndices[1] == ARM::dsub_1 &&
+ SubIndices[2] == ARM::dsub_2 &&
+ SubIndices[3] == ARM::dsub_3 &&
+ SubIndices[4] == ARM::dsub_4 &&
+ SubIndices[5] == ARM::dsub_5 &&
+ SubIndices[6] == ARM::dsub_6 &&
+ SubIndices[7] == ARM::dsub_7);
+ } else if (NumRegs == 4) {
+ if (SubIndices[0] == ARM::qsub_0) {
+ // 4 Q registers -> 1 QQQQ register.
+ return (Size == 512 &&
+ SubIndices[1] == ARM::qsub_1 &&
+ SubIndices[2] == ARM::qsub_2 &&
+ SubIndices[3] == ARM::qsub_3);
+ } else if (SubIndices[0] == ARM::dsub_0) {
+ // 4 D registers -> 1 QQ register.
+ if (Size >= 256 &&
+ SubIndices[1] == ARM::dsub_1 &&
+ SubIndices[2] == ARM::dsub_2 &&
+ SubIndices[3] == ARM::dsub_3) {
+ if (Size == 512)
+ NewSubIdx = ARM::qqsub_0;
+ return true;
+ }
+ } else if (SubIndices[0] == ARM::dsub_4) {
+ // 4 D registers -> 1 QQ register (2nd).
+ if (Size == 512 &&
+ SubIndices[1] == ARM::dsub_5 &&
+ SubIndices[2] == ARM::dsub_6 &&
+ SubIndices[3] == ARM::dsub_7) {
+ NewSubIdx = ARM::qqsub_1;
+ return true;
+ }
+ } else if (SubIndices[0] == ARM::ssub_0) {
+ // 4 S registers -> 1 Q register.
+ if (Size >= 128 &&
+ SubIndices[1] == ARM::ssub_1 &&
+ SubIndices[2] == ARM::ssub_2 &&
+ SubIndices[3] == ARM::ssub_3) {
+ if (Size >= 256)
+ NewSubIdx = ARM::qsub_0;
+ return true;
+ }
+ }
+ } else if (NumRegs == 2) {
+ if (SubIndices[0] == ARM::qsub_0) {
+ // 2 Q registers -> 1 QQ register.
+ if (Size >= 256 && SubIndices[1] == ARM::qsub_1) {
+ if (Size == 512)
+ NewSubIdx = ARM::qqsub_0;
+ return true;
+ }
+ } else if (SubIndices[0] == ARM::qsub_2) {
+ // 2 Q registers -> 1 QQ register (2nd).
+ if (Size == 512 && SubIndices[1] == ARM::qsub_3) {
+ NewSubIdx = ARM::qqsub_1;
+ return true;
+ }
+ } else if (SubIndices[0] == ARM::dsub_0) {
+ // 2 D registers -> 1 Q register.
+ if (Size >= 128 && SubIndices[1] == ARM::dsub_1) {
+ if (Size >= 256)
+ NewSubIdx = ARM::qsub_0;
+ return true;
+ }
+ } else if (SubIndices[0] == ARM::dsub_2) {
+ // 2 D registers -> 1 Q register (2nd).
+ if (Size >= 256 && SubIndices[1] == ARM::dsub_3) {
+ NewSubIdx = ARM::qsub_1;
+ return true;
+ }
+ } else if (SubIndices[0] == ARM::dsub_4) {
+ // 2 D registers -> 1 Q register (3rd).
+ if (Size == 512 && SubIndices[1] == ARM::dsub_5) {
+ NewSubIdx = ARM::qsub_2;
+ return true;
+ }
+ } else if (SubIndices[0] == ARM::dsub_6) {
+ // 2 D registers -> 1 Q register (3rd).
+ if (Size == 512 && SubIndices[1] == ARM::dsub_7) {
+ NewSubIdx = ARM::qsub_3;
+ return true;
+ }
+ } else if (SubIndices[0] == ARM::ssub_0) {
+ // 2 S registers -> 1 D register.
+ if (SubIndices[1] == ARM::ssub_1) {
+ if (Size >= 128)
+ NewSubIdx = ARM::dsub_0;
+ return true;
+ }
+ } else if (SubIndices[0] == ARM::ssub_2) {
+ // 2 S registers -> 1 D register (2nd).
+ if (Size >= 128 && SubIndices[1] == ARM::ssub_3) {
+ NewSubIdx = ARM::dsub_1;
+ return true;
+ }
+ }
+ }
+ return false;
+}
+
+
const TargetRegisterClass *
ARMBaseRegisterInfo::getPointerRegClass(unsigned Kind) const {
return ARM::GPRRegisterClass;
ARMBaseRegisterInfo::getAllocationOrder(const TargetRegisterClass *RC,
unsigned HintType, unsigned HintReg,
const MachineFunction &MF) const {
+ const TargetFrameInfo *TFI = MF.getTarget().getFrameInfo();
// Alternative register allocation orders when favoring even / odd registers
// of register pairs.
return std::make_pair(RC->allocation_order_begin(MF),
RC->allocation_order_end(MF));
- if (!STI.isTargetDarwin() && !hasFP(MF)) {
+ if (!TFI->hasFP(MF)) {
if (!STI.isR9Reserved())
return std::make_pair(GPREven1,
GPREven1 + (sizeof(GPREven1)/sizeof(unsigned)));
return std::make_pair(RC->allocation_order_begin(MF),
RC->allocation_order_end(MF));
- if (!STI.isTargetDarwin() && !hasFP(MF)) {
+ if (!TFI->hasFP(MF)) {
if (!STI.isR9Reserved())
return std::make_pair(GPROdd1,
GPROdd1 + (sizeof(GPROdd1)/sizeof(unsigned)));
}
}
-/// hasFP - Return true if the specified function should have a dedicated frame
-/// pointer register. This is true if the function has variable sized allocas
-/// or if frame pointer elimination is disabled.
-///
-bool ARMBaseRegisterInfo::hasFP(const MachineFunction &MF) const {
+bool ARMBaseRegisterInfo::hasBasePointer(const MachineFunction &MF) const {
const MachineFrameInfo *MFI = MF.getFrameInfo();
- return (NoFramePointerElim ||
- MFI->hasVarSizedObjects() ||
- MFI->isFrameAddressTaken());
-}
+ const ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
-bool ARMBaseRegisterInfo::cannotEliminateFrame(const MachineFunction &MF) const {
- const MachineFrameInfo *MFI = MF.getFrameInfo();
- if (NoFramePointerElim && MFI->hasCalls())
- return true;
- return MFI->hasVarSizedObjects() || MFI->isFrameAddressTaken();
-}
+ if (!EnableBasePointer)
+ return false;
-/// estimateStackSize - Estimate and return the size of the frame.
-static unsigned estimateStackSize(MachineFunction &MF, MachineFrameInfo *MFI) {
- const MachineFrameInfo *FFI = MF.getFrameInfo();
- int Offset = 0;
- for (int i = FFI->getObjectIndexBegin(); i != 0; ++i) {
- int FixedOff = -FFI->getObjectOffset(i);
- if (FixedOff > Offset) Offset = FixedOff;
- }
- for (unsigned i = 0, e = FFI->getObjectIndexEnd(); i != e; ++i) {
- if (FFI->isDeadObjectIndex(i))
- continue;
- Offset += FFI->getObjectSize(i);
- unsigned Align = FFI->getObjectAlignment(i);
- // Adjust to alignment boundary
- Offset = (Offset+Align-1)/Align*Align;
- }
- return (unsigned)Offset;
-}
+ if (needsStackRealignment(MF) && MFI->hasVarSizedObjects())
+ return true;
-/// 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
- }
- }
+ // Thumb has trouble with negative offsets from the FP. Thumb2 has a limited
+ // negative range for ldr/str (255), and thumb1 is positive offsets only.
+ // It's going to be better to use the SP or Base Pointer instead. When there
+ // are variable sized objects, we can't reference off of the SP, so we
+ // reserve a Base Pointer.
+ if (AFI->isThumbFunction() && MFI->hasVarSizedObjects()) {
+ // Conservatively estimate whether the negative offset from the frame
+ // pointer will be sufficient to reach. If a function has a smallish
+ // frame, it's less likely to have lots of spills and callee saved
+ // space, so it's all more likely to be within range of the frame pointer.
+ // If it's wrong, the scavenger will still enable access to work, it just
+ // won't be optimal.
+ if (AFI->isThumb2Function() && MFI->getLocalFrameSize() < 128)
+ return false;
+ return true;
}
- return Limit;
+ return false;
}
-void
-ARMBaseRegisterInfo::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
- 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
- // to combine multiple loads / stores.
- bool CanEliminateFrame = true;
- bool CS1Spilled = false;
- bool LRSpilled = false;
- unsigned NumGPRSpills = 0;
- SmallVector<unsigned, 4> UnspilledCS1GPRs;
- SmallVector<unsigned, 4> UnspilledCS2GPRs;
- ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
-
- // 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();
- const TargetRegisterClass* const *CSRegClasses = getCalleeSavedRegClasses();
- for (unsigned i = 0; CSRegs[i]; ++i) {
- unsigned Reg = CSRegs[i];
- bool Spilled = false;
- if (MF.getRegInfo().isPhysRegUsed(Reg)) {
- AFI->setCSRegisterIsSpilled(Reg);
- Spilled = true;
- CanEliminateFrame = false;
- } else {
- // Check alias registers too.
- for (const unsigned *Aliases = getAliasSet(Reg); *Aliases; ++Aliases) {
- if (MF.getRegInfo().isPhysRegUsed(*Aliases)) {
- Spilled = true;
- CanEliminateFrame = false;
- }
- }
- }
-
- if (CSRegClasses[i] == ARM::GPRRegisterClass) {
- if (Spilled) {
- NumGPRSpills++;
-
- if (!STI.isTargetDarwin()) {
- if (Reg == ARM::LR)
- LRSpilled = true;
- CS1Spilled = true;
- continue;
- }
-
- // Keep track if LR and any of R4, R5, R6, and R7 is spilled.
- switch (Reg) {
- case ARM::LR:
- LRSpilled = true;
- // Fallthrough
- case ARM::R4:
- case ARM::R5:
- case ARM::R6:
- case ARM::R7:
- CS1Spilled = true;
- break;
- default:
- break;
- }
- } else {
- if (!STI.isTargetDarwin()) {
- UnspilledCS1GPRs.push_back(Reg);
- continue;
- }
-
- switch (Reg) {
- case ARM::R4:
- case ARM::R5:
- case ARM::R6:
- case ARM::R7:
- case ARM::LR:
- UnspilledCS1GPRs.push_back(Reg);
- break;
- default:
- UnspilledCS2GPRs.push_back(Reg);
- break;
- }
- }
- }
- }
-
- bool ForceLRSpill = false;
- if (!LRSpilled && AFI->isThumb1OnlyFunction()) {
- unsigned FnSize = TII.GetFunctionSizeInBytes(MF);
- // Force LR to be spilled if the Thumb function size is > 2048. This enables
- // use of BL to implement far jump. If it turns out that it's not needed
- // then the branch fix up path will undo it.
- if (FnSize >= (1 << 11)) {
- CanEliminateFrame = false;
- ForceLRSpill = true;
- }
- }
-
- bool ExtraCSSpill = false;
- if (!CanEliminateFrame || cannotEliminateFrame(MF)) {
- AFI->setHasStackFrame(true);
-
- // 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) {
- MF.getRegInfo().setPhysRegUsed(ARM::LR);
- AFI->setCSRegisterIsSpilled(ARM::LR);
- NumGPRSpills++;
- UnspilledCS1GPRs.erase(std::find(UnspilledCS1GPRs.begin(),
- UnspilledCS1GPRs.end(), (unsigned)ARM::LR));
- ForceLRSpill = false;
- ExtraCSSpill = true;
- }
-
- // Darwin ABI requires FP to point to the stack slot that contains the
- // previous FP.
- if (STI.isTargetDarwin() || hasFP(MF)) {
- MF.getRegInfo().setPhysRegUsed(FramePtr);
- NumGPRSpills++;
- }
+bool ARMBaseRegisterInfo::canRealignStack(const MachineFunction &MF) const {
+ const MachineFrameInfo *MFI = MF.getFrameInfo();
+ const ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+ // We can't realign the stack if:
+ // 1. Dynamic stack realignment is explicitly disabled,
+ // 2. This is a Thumb1 function (it's not useful, so we don't bother), or
+ // 3. There are VLAs in the function and the base pointer is disabled.
+ return (RealignStack && !AFI->isThumb1OnlyFunction() &&
+ (!MFI->hasVarSizedObjects() || EnableBasePointer));
+}
- // If stack and double are 8-byte aligned and we are spilling an odd number
- // of GPRs. Spill one extra callee save GPR so we won't have to pad between
- // the integer and double callee save areas.
- unsigned TargetAlign = MF.getTarget().getFrameInfo()->getStackAlignment();
- if (TargetAlign == 8 && (NumGPRSpills & 1)) {
- if (CS1Spilled && !UnspilledCS1GPRs.empty()) {
- for (unsigned i = 0, e = UnspilledCS1GPRs.size(); i != e; ++i) {
- unsigned Reg = UnspilledCS1GPRs[i];
- // Don't spill high register if the function is thumb1
- if (!AFI->isThumb1OnlyFunction() ||
- isARMLowRegister(Reg) || Reg == ARM::LR) {
- MF.getRegInfo().setPhysRegUsed(Reg);
- AFI->setCSRegisterIsSpilled(Reg);
- if (!isReservedReg(MF, Reg))
- ExtraCSSpill = true;
- break;
- }
- }
- } else if (!UnspilledCS2GPRs.empty() &&
- !AFI->isThumb1OnlyFunction()) {
- unsigned Reg = UnspilledCS2GPRs.front();
- MF.getRegInfo().setPhysRegUsed(Reg);
- AFI->setCSRegisterIsSpilled(Reg);
- if (!isReservedReg(MF, Reg))
- ExtraCSSpill = true;
- }
- }
+bool ARMBaseRegisterInfo::
+needsStackRealignment(const MachineFunction &MF) const {
+ const MachineFrameInfo *MFI = MF.getFrameInfo();
+ const Function *F = MF.getFunction();
+ unsigned StackAlign = MF.getTarget().getFrameInfo()->getStackAlignment();
+ bool requiresRealignment = ((MFI->getLocalFrameMaxAlign() > StackAlign) ||
+ F->hasFnAttr(Attribute::StackAlignment));
- // 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. Thumb1 needs a spill slot for stack pointer
- // adjustments also, even when the frame itself is small.
- if (RS && !ExtraCSSpill) {
- MachineFrameInfo *MFI = MF.getFrameInfo();
- if (estimateStackSize(MF, MFI) >= estimateRSStackSizeLimit(MF)
- || AFI->isThumb1OnlyFunction()) {
- // 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--;
- }
- }
- while (NumExtras && !UnspilledCS2GPRs.empty()) {
- unsigned Reg = UnspilledCS2GPRs.back();
- UnspilledCS2GPRs.pop_back();
- if (!isReservedReg(MF, Reg)) {
- Extras.push_back(Reg);
- 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::GPRRegisterClass;
- RS->setScavengingFrameIndex(MFI->CreateStackObject(RC->getSize(),
- RC->getAlignment()));
- }
- }
- }
- }
+ return requiresRealignment && canRealignStack(MF);
+}
- if (ForceLRSpill) {
- MF.getRegInfo().setPhysRegUsed(ARM::LR);
- AFI->setCSRegisterIsSpilled(ARM::LR);
- AFI->setLRIsSpilledForFarJump(true);
- }
+bool ARMBaseRegisterInfo::
+cannotEliminateFrame(const MachineFunction &MF) const {
+ const MachineFrameInfo *MFI = MF.getFrameInfo();
+ if (DisableFramePointerElim(MF) && MFI->adjustsStack())
+ return true;
+ return MFI->hasVarSizedObjects() || MFI->isFrameAddressTaken()
+ || needsStackRealignment(MF);
}
unsigned ARMBaseRegisterInfo::getRARegister() const {
return ARM::LR;
}
-unsigned ARMBaseRegisterInfo::getFrameRegister(MachineFunction &MF) const {
- if (STI.isTargetDarwin() || hasFP(MF))
+unsigned
+ARMBaseRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
+ const TargetFrameInfo *TFI = MF.getTarget().getFrameInfo();
+
+ if (TFI->hasFP(MF))
return FramePtr;
return ARM::SP;
}
}
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:
- return isReservedReg(MF, ARM::R7) ? 0 : ARM::R6;
+ return (isReservedReg(MF, ARM::R7) || isReservedReg(MF, ARM::R6))
+ ? 0 : ARM::R6;
case ARM::R9:
return isReservedReg(MF, ARM::R9) ? 0 :ARM::R8;
case ARM::R11:
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 isReservedReg(MF, ARM::R7) ? 0 : ARM::R7;
+ return (isReservedReg(MF, ARM::R7) || isReservedReg(MF, ARM::R6))
+ ? 0 : ARM::R7;
case ARM::R8:
return isReservedReg(MF, ARM::R9) ? 0 :ARM::R9;
case ARM::R10:
unsigned PredReg) const {
MachineFunction &MF = *MBB.getParent();
MachineConstantPool *ConstantPool = MF.getConstantPool();
- Constant *C =
+ const Constant *C =
ConstantInt::get(Type::getInt32Ty(MF.getFunction()->getContext()), Val);
unsigned Idx = ConstantPool->getConstantPoolIndex(C, 4);
BuildMI(MBB, MBBI, dl, TII.get(ARM::LDRcp))
.addReg(DestReg, getDefRegState(true), SubIdx)
.addConstantPoolIndex(Idx)
- .addReg(0).addImm(0).addImm(Pred).addReg(PredReg);
+ .addImm(0).addImm(Pred).addReg(PredReg);
}
bool ARMBaseRegisterInfo::
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
-// add/sub sp brackets around call sites. Returns true if the call frame is
-// included as part of the stack frame.
bool ARMBaseRegisterInfo::
-hasReservedCallFrame(MachineFunction &MF) const {
- const MachineFrameInfo *FFI = MF.getFrameInfo();
- unsigned CFSize = FFI->getMaxCallFrameSize();
- // It's not always a good idea to include the call frame as part of the
- // stack frame. ARM (especially Thumb) has small immediate offset to
- // address the stack frame. So a large call frame can cause poor codegen
- // and may even makes it impossible to scavenge a register.
- if (CFSize >= ((1 << 12) - 1) / 2) // Half of imm12
- return false;
+requiresFrameIndexScavenging(const MachineFunction &MF) const {
+ return true;
+}
- return !MF.getFrameInfo()->hasVarSizedObjects();
+bool ARMBaseRegisterInfo::
+requiresVirtualBaseRegisters(const MachineFunction &MF) const {
+ return EnableLocalStackAlloc;
}
static void
void ARMBaseRegisterInfo::
eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) const {
- if (!hasReservedCallFrame(MF)) {
+ const TargetFrameInfo *TFI = MF.getTarget().getFrameInfo();
+ if (!TFI->hasReservedCallFrame(MF)) {
// If we have alloca, convert as follows:
// ADJCALLSTACKDOWN -> sub, sp, sp, amount
// ADJCALLSTACKUP -> add, sp, sp, amount
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
assert(!AFI->isThumb1OnlyFunction() &&
- "This eliminateCallFramePseudoInstr does not suppor Thumb1!");
+ "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();
- // FIXME: Thumb2 version of ADJCALLSTACKUP and ADJCALLSTACKDOWN?
+ 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();
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) : (unsigned) ARM::R12;
- assert(!AFI->isThumb1OnlyFunction());
- return Reg;
+int64_t ARMBaseRegisterInfo::
+getFrameIndexInstrOffset(const MachineInstr *MI, int Idx) const {
+ const TargetInstrDesc &Desc = MI->getDesc();
+ unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
+ int64_t InstrOffs = 0;;
+ int Scale = 1;
+ unsigned ImmIdx = 0;
+ switch (AddrMode) {
+ case ARMII::AddrModeT2_i8:
+ case ARMII::AddrModeT2_i12:
+ case ARMII::AddrMode_i12:
+ InstrOffs = MI->getOperand(Idx+1).getImm();
+ Scale = 1;
+ break;
+ case ARMII::AddrMode5: {
+ // VFP address mode.
+ const MachineOperand &OffOp = MI->getOperand(Idx+1);
+ InstrOffs = ARM_AM::getAM5Offset(OffOp.getImm());
+ if (ARM_AM::getAM5Op(OffOp.getImm()) == ARM_AM::sub)
+ InstrOffs = -InstrOffs;
+ Scale = 4;
+ break;
+ }
+ case ARMII::AddrMode2: {
+ ImmIdx = Idx+2;
+ InstrOffs = ARM_AM::getAM2Offset(MI->getOperand(ImmIdx).getImm());
+ if (ARM_AM::getAM2Op(MI->getOperand(ImmIdx).getImm()) == ARM_AM::sub)
+ InstrOffs = -InstrOffs;
+ break;
+ }
+ case ARMII::AddrMode3: {
+ ImmIdx = Idx+2;
+ InstrOffs = ARM_AM::getAM3Offset(MI->getOperand(ImmIdx).getImm());
+ if (ARM_AM::getAM3Op(MI->getOperand(ImmIdx).getImm()) == ARM_AM::sub)
+ InstrOffs = -InstrOffs;
+ break;
+ }
+ case ARMII::AddrModeT1_s: {
+ ImmIdx = Idx+1;
+ InstrOffs = MI->getOperand(ImmIdx).getImm();
+ Scale = 4;
+ break;
+ }
+ default:
+ llvm_unreachable("Unsupported addressing mode!");
+ break;
+ }
+
+ return InstrOffs * Scale;
+}
+
+/// needsFrameBaseReg - Returns true if the instruction's frame index
+/// reference would be better served by a base register other than FP
+/// or SP. Used by LocalStackFrameAllocation to determine which frame index
+/// references it should create new base registers for.
+bool ARMBaseRegisterInfo::
+needsFrameBaseReg(MachineInstr *MI, int64_t Offset) const {
+ for (unsigned i = 0; !MI->getOperand(i).isFI(); ++i) {
+ assert(i < MI->getNumOperands() &&"Instr doesn't have FrameIndex operand!");
+ }
+
+ // It's the load/store FI references that cause issues, as it can be difficult
+ // to materialize the offset if it won't fit in the literal field. Estimate
+ // based on the size of the local frame and some conservative assumptions
+ // about the rest of the stack frame (note, this is pre-regalloc, so
+ // we don't know everything for certain yet) whether this offset is likely
+ // to be out of range of the immediate. Return true if so.
+
+ // We only generate virtual base registers for loads and stores, so
+ // return false for everything else.
+ unsigned Opc = MI->getOpcode();
+ switch (Opc) {
+ case ARM::LDRi12: case ARM::LDRH: case ARM::LDRBi12:
+ case ARM::STRi12: case ARM::STRH: case ARM::STRBi12:
+ case ARM::t2LDRi12: case ARM::t2LDRi8:
+ case ARM::t2STRi12: case ARM::t2STRi8:
+ case ARM::VLDRS: case ARM::VLDRD:
+ case ARM::VSTRS: case ARM::VSTRD:
+ case ARM::tSTRspi: case ARM::tLDRspi:
+ if (ForceAllBaseRegAlloc)
+ return true;
+ break;
+ default:
+ return false;
+ }
+
+ // Without a virtual base register, if the function has variable sized
+ // objects, all fixed-size local references will be via the frame pointer,
+ // Approximate the offset and see if it's legal for the instruction.
+ // Note that the incoming offset is based on the SP value at function entry,
+ // so it'll be negative.
+ MachineFunction &MF = *MI->getParent()->getParent();
+ const TargetFrameInfo *TFI = MF.getTarget().getFrameInfo();
+ MachineFrameInfo *MFI = MF.getFrameInfo();
+ ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+
+ // Estimate an offset from the frame pointer.
+ // Conservatively assume all callee-saved registers get pushed. R4-R6
+ // will be earlier than the FP, so we ignore those.
+ // R7, LR
+ int64_t FPOffset = Offset - 8;
+ // ARM and Thumb2 functions also need to consider R8-R11 and D8-D15
+ if (!AFI->isThumbFunction() || !AFI->isThumb1OnlyFunction())
+ FPOffset -= 80;
+ // Estimate an offset from the stack pointer.
+ // The incoming offset is relating to the SP at the start of the function,
+ // but when we access the local it'll be relative to the SP after local
+ // allocation, so adjust our SP-relative offset by that allocation size.
+ Offset = -Offset;
+ Offset += MFI->getLocalFrameSize();
+ // Assume that we'll have at least some spill slots allocated.
+ // FIXME: This is a total SWAG number. We should run some statistics
+ // and pick a real one.
+ Offset += 128; // 128 bytes of spill slots
+
+ // If there is a frame pointer, try using it.
+ // The FP is only available if there is no dynamic realignment. We
+ // don't know for sure yet whether we'll need that, so we guess based
+ // on whether there are any local variables that would trigger it.
+ unsigned StackAlign = MF.getTarget().getFrameInfo()->getStackAlignment();
+ if (TFI->hasFP(MF) &&
+ !((MFI->getLocalFrameMaxAlign() > StackAlign) && canRealignStack(MF))) {
+ if (isFrameOffsetLegal(MI, FPOffset))
+ return false;
+ }
+ // If we can reference via the stack pointer, try that.
+ // FIXME: This (and the code that resolves the references) can be improved
+ // to only disallow SP relative references in the live range of
+ // the VLA(s). In practice, it's unclear how much difference that
+ // would make, but it may be worth doing.
+ if (!MFI->hasVarSizedObjects() && isFrameOffsetLegal(MI, Offset))
+ return false;
+
+ // The offset likely isn't legal, we want to allocate a virtual base register.
+ return true;
+}
+
+/// materializeFrameBaseRegister - Insert defining instruction(s) for
+/// BaseReg to be a pointer to FrameIdx before insertion point I.
+void ARMBaseRegisterInfo::
+materializeFrameBaseRegister(MachineBasicBlock::iterator I, unsigned BaseReg,
+ int FrameIdx, int64_t Offset) const {
+ ARMFunctionInfo *AFI =
+ I->getParent()->getParent()->getInfo<ARMFunctionInfo>();
+ unsigned ADDriOpc = !AFI->isThumbFunction() ? ARM::ADDri :
+ (AFI->isThumb1OnlyFunction() ? ARM::tADDrSPi : ARM::t2ADDri);
+
+ MachineInstrBuilder MIB =
+ BuildMI(*I->getParent(), I, I->getDebugLoc(), TII.get(ADDriOpc), BaseReg)
+ .addFrameIndex(FrameIdx).addImm(Offset);
+ if (!AFI->isThumb1OnlyFunction())
+ AddDefaultCC(AddDefaultPred(MIB));
+}
+
+void
+ARMBaseRegisterInfo::resolveFrameIndex(MachineBasicBlock::iterator I,
+ unsigned BaseReg, int64_t Offset) const {
+ MachineInstr &MI = *I;
+ MachineBasicBlock &MBB = *MI.getParent();
+ MachineFunction &MF = *MBB.getParent();
+ ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
+ int Off = Offset; // ARM doesn't need the general 64-bit offsets
+ unsigned i = 0;
+
+ assert(!AFI->isThumb1OnlyFunction() &&
+ "This resolveFrameIndex does not support Thumb1!");
+
+ while (!MI.getOperand(i).isFI()) {
+ ++i;
+ assert(i < MI.getNumOperands() && "Instr doesn't have FrameIndex operand!");
+ }
+ bool Done = false;
+ if (!AFI->isThumbFunction())
+ Done = rewriteARMFrameIndex(MI, i, BaseReg, Off, TII);
+ else {
+ assert(AFI->isThumb2Function());
+ Done = rewriteT2FrameIndex(MI, i, BaseReg, Off, TII);
+ }
+ assert (Done && "Unable to resolve frame index!");
+}
+
+bool ARMBaseRegisterInfo::isFrameOffsetLegal(const MachineInstr *MI,
+ int64_t Offset) const {
+ const TargetInstrDesc &Desc = MI->getDesc();
+ unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
+ unsigned i = 0;
+
+ while (!MI->getOperand(i).isFI()) {
+ ++i;
+ assert(i < MI->getNumOperands() &&"Instr doesn't have FrameIndex operand!");
+ }
+
+ // AddrMode4 and AddrMode6 cannot handle any offset.
+ if (AddrMode == ARMII::AddrMode4 || AddrMode == ARMII::AddrMode6)
+ return Offset == 0;
+
+ unsigned NumBits = 0;
+ unsigned Scale = 1;
+ bool isSigned = true;
+ switch (AddrMode) {
+ case ARMII::AddrModeT2_i8:
+ case ARMII::AddrModeT2_i12:
+ // i8 supports only negative, and i12 supports only positive, so
+ // based on Offset sign, consider the appropriate instruction
+ Scale = 1;
+ if (Offset < 0) {
+ NumBits = 8;
+ Offset = -Offset;
+ } else {
+ NumBits = 12;
+ }
+ break;
+ case ARMII::AddrMode5:
+ // VFP address mode.
+ NumBits = 8;
+ Scale = 4;
+ break;
+ case ARMII::AddrMode_i12:
+ case ARMII::AddrMode2:
+ NumBits = 12;
+ break;
+ case ARMII::AddrMode3:
+ NumBits = 8;
+ break;
+ case ARMII::AddrModeT1_s:
+ NumBits = 5;
+ Scale = 4;
+ isSigned = false;
+ break;
+ default:
+ llvm_unreachable("Unsupported addressing mode!");
+ break;
+ }
+
+ Offset += getFrameIndexInstrOffset(MI, i);
+ // Make sure the offset is encodable for instructions that scale the
+ // immediate.
+ if ((Offset & (Scale-1)) != 0)
+ return false;
+
+ if (isSigned && Offset < 0)
+ Offset = -Offset;
+
+ unsigned Mask = (1 << NumBits) - 1;
+ if ((unsigned)Offset <= Mask * Scale)
+ return true;
+
+ return false;
}
void
MachineInstr &MI = *II;
MachineBasicBlock &MBB = *MI.getParent();
MachineFunction &MF = *MBB.getParent();
- const MachineFrameInfo *MFI = MF.getFrameInfo();
+ const ARMFrameInfo *TFI =
+ static_cast<const ARMFrameInfo*>(MF.getTarget().getFrameInfo());
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
assert(!AFI->isThumb1OnlyFunction() &&
"This eliminateFrameIndex does not support Thumb1!");
assert(i < MI.getNumOperands() && "Instr doesn't have FrameIndex operand!");
}
- unsigned FrameReg = ARM::SP;
int FrameIndex = MI.getOperand(i).getIndex();
- int Offset = MFI->getObjectOffset(FrameIndex) + MFI->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) && 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();
+ unsigned FrameReg;
+
+ int Offset = TFI->ResolveFrameIndexReference(MF, FrameIndex, FrameReg, SPAdj);
+
+ // Special handling of dbg_value instructions.
+ if (MI.isDebugValue()) {
+ MI.getOperand(i). ChangeToRegister(FrameReg, false /*isDef*/);
+ MI.getOperand(i+1).ChangeToImmediate(Offset);
+ return;
}
- // modify MI as necessary to handle as much of 'Offset' as possible
+ // 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);
// as much as possible above, handle the rest, providing a register that is
// SP+LargeImm.
assert((Offset ||
- (MI.getDesc().TSFlags & ARMII::AddrModeMask) == ARMII::AddrMode4) &&
+ (MI.getDesc().TSFlags & ARMII::AddrModeMask) == ARMII::AddrMode4 ||
+ (MI.getDesc().TSFlags & ARMII::AddrModeMask) == ARMII::AddrMode6) &&
"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::GPRRegisterClass, AFI);
- if (ScratchReg == 0)
- // No register is "free". Scavenge a register.
- ScratchReg = RS->scavengeRegister(ARM::GPRRegisterClass, II, SPAdj);
+ 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();
if (Offset == 0)
- // Must be addrmode4.
+ // Must be addrmode4/6.
MI.getOperand(i).ChangeToRegister(FrameReg, false, false, false);
else {
+ ScratchReg = MF.getRegInfo().createVirtualRegister(ARM::GPRRegisterClass);
if (!AFI->isThumbFunction())
emitARMRegPlusImmediate(MBB, II, MI.getDebugLoc(), ScratchReg, FrameReg,
Offset, Pred, PredReg, TII);
}
}
-/// Move iterator pass 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,
- int Opc1, int Opc2, unsigned Area,
- const ARMSubtarget &STI) {
- while (MBBI != MBB.end() &&
- ((MBBI->getOpcode() == Opc1) || (MBBI->getOpcode() == Opc2)) &&
- MBBI->getOperand(1).isFI()) {
- if (Area != 0) {
- bool Done = false;
- unsigned Category = 0;
- switch (MBBI->getOperand(0).getReg()) {
- case ARM::R4: case ARM::R5: case ARM::R6: case ARM::R7:
- case ARM::LR:
- Category = 1;
- break;
- case ARM::R8: case ARM::R9: case ARM::R10: case ARM::R11:
- Category = STI.isTargetDarwin() ? 2 : 1;
- break;
- case ARM::D8: case ARM::D9: case ARM::D10: case ARM::D11:
- case ARM::D12: case ARM::D13: case ARM::D14: case ARM::D15:
- Category = 3;
- break;
- default:
- Done = true;
- break;
- }
- if (Done || Category != Area)
- break;
- }
-
- ++MBBI;
- }
-}
-
-void ARMBaseRegisterInfo::
-emitPrologue(MachineFunction &MF) const {
- MachineBasicBlock &MBB = MF.front();
- MachineBasicBlock::iterator MBBI = MBB.begin();
- MachineFrameInfo *MFI = MF.getFrameInfo();
- ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
- assert(!AFI->isThumb1OnlyFunction() &&
- "This emitPrologue does not suppor Thumb1!");
- bool isARM = !AFI->isThumbFunction();
- unsigned VARegSaveSize = AFI->getVarArgsRegSaveSize();
- unsigned NumBytes = MFI->getStackSize();
- const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
- DebugLoc dl = (MBBI != MBB.end() ?
- MBBI->getDebugLoc() : DebugLoc::getUnknownLoc());
-
- // Determine the sizes of each callee-save spill areas and record which frame
- // belongs to which callee-save spill areas.
- 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(isARM, MBB, MBBI, dl, TII, -VARegSaveSize);
-
- if (!AFI->hasStackFrame()) {
- if (NumBytes != 0)
- emitSPUpdate(isARM, MBB, MBBI, dl, TII, -NumBytes);
- return;
- }
-
- for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
- unsigned Reg = CSI[i].getReg();
- int FI = CSI[i].getFrameIdx();
- switch (Reg) {
- case ARM::R4:
- case ARM::R5:
- case ARM::R6:
- case ARM::R7:
- case ARM::LR:
- if (Reg == FramePtr)
- FramePtrSpillFI = FI;
- AFI->addGPRCalleeSavedArea1Frame(FI);
- GPRCS1Size += 4;
- break;
- case ARM::R8:
- case ARM::R9:
- case ARM::R10:
- case ARM::R11:
- if (Reg == FramePtr)
- FramePtrSpillFI = FI;
- if (STI.isTargetDarwin()) {
- AFI->addGPRCalleeSavedArea2Frame(FI);
- GPRCS2Size += 4;
- } else {
- AFI->addGPRCalleeSavedArea1Frame(FI);
- GPRCS1Size += 4;
- }
- break;
- default:
- AFI->addDPRCalleeSavedAreaFrame(FI);
- DPRCSSize += 8;
- }
- }
-
- // Build the new SUBri to adjust SP for integer callee-save spill area 1.
- 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(ADDriOpc), FramePtr)
- .addFrameIndex(FramePtrSpillFI).addImm(0);
- AddDefaultCC(AddDefaultPred(MIB));
- }
-
- // Build the new SUBri to adjust SP for integer callee-save spill area 2.
- emitSPUpdate(isARM, MBB, MBBI, dl, TII, -GPRCS2Size);
-
- // Build the new SUBri to adjust SP for FP callee-save spill area.
- 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);
- AFI->setGPRCalleeSavedArea1Offset(GPRCS1Offset);
- AFI->setGPRCalleeSavedArea2Offset(GPRCS2Offset);
- AFI->setDPRCalleeSavedAreaOffset(DPRCSOffset);
-
- NumBytes = DPRCSOffset;
- if (NumBytes) {
- // Insert it after all the callee-save spills.
- movePastCSLoadStoreOps(MBB, MBBI, ARM::FSTD, 0, 3, STI);
- emitSPUpdate(isARM, MBB, MBBI, dl, TII, -NumBytes);
- }
-
- if (STI.isTargetELF() && hasFP(MF)) {
- MFI->setOffsetAdjustment(MFI->getOffsetAdjustment() -
- AFI->getFramePtrSpillOffset());
- }
-
- AFI->setGPRCalleeSavedArea1Size(GPRCS1Size);
- AFI->setGPRCalleeSavedArea2Size(GPRCS2Size);
- AFI->setDPRCalleeSavedAreaSize(DPRCSSize);
-}
-
-static bool isCalleeSavedRegister(unsigned Reg, const unsigned *CSRegs) {
- for (unsigned i = 0; CSRegs[i]; ++i)
- if (Reg == CSRegs[i])
- return true;
- return false;
-}
-
-static bool isCSRestore(MachineInstr *MI,
- const ARMBaseInstrInfo &TII,
- const unsigned *CSRegs) {
- return ((MI->getOpcode() == (int)ARM::FLDD ||
- 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 {
- MachineBasicBlock::iterator MBBI = prior(MBB.end());
- 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 suppor Thumb1!");
- bool isARM = !AFI->isThumbFunction();
-
- unsigned VARegSaveSize = AFI->getVarArgsRegSaveSize();
- int NumBytes = (int)MFI->getStackSize();
-
- if (!AFI->hasStackFrame()) {
- if (NumBytes != 0)
- emitSPUpdate(isARM, MBB, MBBI, dl, TII, NumBytes);
- } else {
- // Unwind MBBI to point to first LDR / FLDD.
- const unsigned *CSRegs = getCalleeSavedRegs();
- if (MBBI != MBB.begin()) {
- do
- --MBBI;
- while (MBBI != MBB.begin() && isCSRestore(MBBI, TII, CSRegs));
- if (!isCSRestore(MBBI, TII, CSRegs))
- ++MBBI;
- }
-
- // Move SP to start of FP callee save spill area.
- NumBytes -= (AFI->getGPRCalleeSavedArea1Size() +
- AFI->getGPRCalleeSavedArea2Size() +
- AFI->getDPRCalleeSavedAreaSize());
-
- // Darwin ABI requires FP to point to the stack slot that contains the
- // previous FP.
- 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 (HasFP ||
- AFI->getGPRCalleeSavedArea2Size() ||
- AFI->getDPRCalleeSavedAreaSize() ||
- 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(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(isARM, MBB, MBBI, dl, TII, AFI->getDPRCalleeSavedAreaSize());
-
- // Move SP to start of integer callee save spill area 1.
- 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, ARM::LDR, ARM::t2LDRi12, 1, STI);
- emitSPUpdate(isARM, MBB, MBBI, dl, TII, AFI->getGPRCalleeSavedArea1Size());
- }
-
- if (VARegSaveSize)
- emitSPUpdate(isARM, MBB, MBBI, dl, TII, VARegSaveSize);
-}
-
#include "ARMGenRegisterInfo.inc"
projects / oota-llvm.git / blobdiff