-//=====- PPCFrameLowering.cpp - PPC Frame Information -----------*- C++ -*-===//
+//===-- PPCFrameLowering.cpp - PPC Frame Information ----------------------===//
//
// The LLVM Compiler Infrastructure
//
//===----------------------------------------------------------------------===//
#include "PPCFrameLowering.h"
+#include "PPCInstrBuilder.h"
#include "PPCInstrInfo.h"
#include "PPCMachineFunctionInfo.h"
-#include "llvm/Function.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RegisterScavenging.h"
+#include "llvm/IR/Function.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
/// VRRegNo - Map from a numbered VR register to its enum value.
///
-static const unsigned short VRRegNo[] = {
+static const uint16_t VRRegNo[] = {
PPC::V0 , PPC::V1 , PPC::V2 , PPC::V3 , PPC::V4 , PPC::V5 , PPC::V6 , PPC::V7 ,
PPC::V8 , PPC::V9 , PPC::V10, PPC::V11, PPC::V12, PPC::V13, PPC::V14, PPC::V15,
PPC::V16, PPC::V17, PPC::V18, PPC::V19, PPC::V20, PPC::V21, PPC::V22, PPC::V23,
/// to manipulate the VRSAVE register, even though it uses vector registers.
/// This can happen when the only registers used are known to be live in or out
/// of the function. Remove all of the VRSAVE related code from the function.
+/// FIXME: The removal of the code results in a compile failure at -O0 when the
+/// function contains a function call, as the GPR containing original VRSAVE
+/// contents is spilled and reloaded around the call. Without the prolog code,
+/// the spill instruction refers to an undefined register. This code needs
+/// to account for all uses of that GPR.
static void RemoveVRSaveCode(MachineInstr *MI) {
MachineBasicBlock *Entry = MI->getParent();
MachineFunction *MF = Entry->getParent();
// epilog blocks.
for (MachineFunction::iterator I = MF->begin(), E = MF->end(); I != E; ++I) {
// If last instruction is a return instruction, add an epilogue
- if (!I->empty() && I->back().getDesc().isReturn()) {
+ if (!I->empty() && I->back().isReturn()) {
bool FoundIt = false;
for (MBBI = I->end(); MBBI != I->begin(); ) {
--MBBI;
for (MachineRegisterInfo::livein_iterator
I = MF->getRegInfo().livein_begin(),
E = MF->getRegInfo().livein_end(); I != E; ++I) {
- unsigned RegNo = PPCRegisterInfo::getRegisterNumbering(I->first);
+ unsigned RegNo = getPPCRegisterNumbering(I->first);
if (VRRegNo[RegNo] == I->first) // If this really is a vector reg.
UsedRegMask &= ~(1 << (31-RegNo)); // Doesn't need to be marked.
}
for (MachineRegisterInfo::liveout_iterator
I = MF->getRegInfo().liveout_begin(),
E = MF->getRegInfo().liveout_end(); I != E; ++I) {
- unsigned RegNo = PPCRegisterInfo::getRegisterNumbering(*I);
+ unsigned RegNo = getPPCRegisterNumbering(*I);
if (VRRegNo[RegNo] == *I) // If this really is a vector reg.
UsedRegMask &= ~(1 << (31-RegNo)); // Doesn't need to be marked.
}
MI->eraseFromParent();
}
+static bool spillsCR(const MachineFunction &MF) {
+ const PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>();
+ return FuncInfo->isCRSpilled();
+}
+
/// determineFrameLayout - Determine the size of the frame and maximum call
/// frame size.
void PPCFrameLowering::determineFrameLayout(MachineFunction &MF) const {
// If we are a leaf function, and use up to 224 bytes of stack space,
// don't have a frame pointer, calls, or dynamic alloca then we do not need
- // to adjust the stack pointer (we fit in the Red Zone).
- bool DisableRedZone = MF.getFunction()->hasFnAttr(Attribute::NoRedZone);
- // FIXME SVR4 The 32-bit SVR4 ABI has no red zone.
+ // to adjust the stack pointer (we fit in the Red Zone). For 64-bit
+ // SVR4, we also require a stack frame if we need to spill the CR,
+ // since this spill area is addressed relative to the stack pointer.
+ bool DisableRedZone = MF.getFunction()->getAttributes().
+ hasAttribute(AttributeSet::FunctionIndex, Attribute::NoRedZone);
+ // FIXME SVR4 The 32-bit SVR4 ABI has no red zone. However, it can
+ // still generate stackless code if all local vars are reg-allocated.
+ // Try: (FrameSize <= 224
+ // || (FrameSize == 0 && Subtarget.isPPC32 && Subtarget.isSVR4ABI()))
if (!DisableRedZone &&
FrameSize <= 224 && // Fits in red zone.
!MFI->hasVarSizedObjects() && // No dynamic alloca.
!MFI->adjustsStack() && // No calls.
+ !(Subtarget.isPPC64() && // No 64-bit SVR4 CRsave.
+ Subtarget.isSVR4ABI()
+ && spillsCR(MF)) &&
(!ALIGN_STACK || MaxAlign <= TargetAlign)) { // No special alignment.
// No need for frame
MFI->setStackSize(0);
// Naked functions have no stack frame pushed, so we don't have a frame
// pointer.
- if (MF.getFunction()->hasFnAttr(Attribute::Naked))
+ if (MF.getFunction()->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
+ Attribute::Naked))
return false;
- return DisableFramePointerElim(MF) || MFI->hasVarSizedObjects() ||
- (GuaranteedTailCallOpt && MF.getInfo<PPCFunctionInfo>()->hasFastCall());
+ return MF.getTarget().Options.DisableFramePointerElim(MF) ||
+ MFI->hasVarSizedObjects() ||
+ (MF.getTarget().Options.GuaranteedTailCallOpt &&
+ MF.getInfo<PPCFunctionInfo>()->hasFastCall());
}
MachineModuleInfo &MMI = MF.getMMI();
DebugLoc dl;
bool needsFrameMoves = MMI.hasDebugInfo() ||
- !MF.getFunction()->doesNotThrow() ||
- UnwindTablesMandatory;
+ MF.getFunction()->needsUnwindTableEntry();
// Prepare for frame info.
MCSymbol *FrameLabel = 0;
// Scan the prolog, looking for an UPDATE_VRSAVE instruction. If we find it,
// process it.
- for (unsigned i = 0; MBBI != MBB.end(); ++i, ++MBBI) {
- if (MBBI->getOpcode() == PPC::UPDATE_VRSAVE) {
- HandleVRSaveUpdate(MBBI, TII);
- break;
+ if (!Subtarget.isSVR4ABI())
+ for (unsigned i = 0; MBBI != MBB.end(); ++i, ++MBBI) {
+ if (MBBI->getOpcode() == PPC::UPDATE_VRSAVE) {
+ HandleVRSaveUpdate(MBBI, TII);
+ break;
+ }
}
- }
// Move MBBI back to the beginning of the function.
MBBI = MBB.begin();
BuildMI(MBB, MBBI, dl, TII.get(PPC::MFLR), PPC::R0);
if (HasFP)
+ // FIXME: On PPC32 SVR4, FPOffset is negative and access to negative
+ // offsets of R1 is not allowed.
BuildMI(MBB, MBBI, dl, TII.get(PPC::STW))
.addReg(PPC::R31)
.addImm(FPOffset)
BuildMI(MBB, MBBI, dl, TII.get(PPC::SUBFIC) ,PPC::R0)
.addReg(PPC::R0, RegState::Kill)
.addImm(NegFrameSize);
- BuildMI(MBB, MBBI, dl, TII.get(PPC::STWUX))
- .addReg(PPC::R1)
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::STWUX), PPC::R1)
+ .addReg(PPC::R1, RegState::Kill)
.addReg(PPC::R1)
.addReg(PPC::R0);
} else if (isInt<16>(NegFrameSize)) {
BuildMI(MBB, MBBI, dl, TII.get(PPC::ORI), PPC::R0)
.addReg(PPC::R0, RegState::Kill)
.addImm(NegFrameSize & 0xFFFF);
- BuildMI(MBB, MBBI, dl, TII.get(PPC::STWUX))
- .addReg(PPC::R1)
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::STWUX), PPC::R1)
+ .addReg(PPC::R1, RegState::Kill)
.addReg(PPC::R1)
.addReg(PPC::R0);
}
BuildMI(MBB, MBBI, dl, TII.get(PPC::SUBFIC8), PPC::X0)
.addReg(PPC::X0)
.addImm(NegFrameSize);
- BuildMI(MBB, MBBI, dl, TII.get(PPC::STDUX))
- .addReg(PPC::X1)
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::STDUX), PPC::X1)
+ .addReg(PPC::X1, RegState::Kill)
.addReg(PPC::X1)
.addReg(PPC::X0);
} else if (isInt<16>(NegFrameSize)) {
BuildMI(MBB, MBBI, dl, TII.get(PPC::ORI8), PPC::X0)
.addReg(PPC::X0, RegState::Kill)
.addImm(NegFrameSize & 0xFFFF);
- BuildMI(MBB, MBBI, dl, TII.get(PPC::STDUX))
- .addReg(PPC::X1)
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::STDUX), PPC::X1)
+ .addReg(PPC::X1, RegState::Kill)
.addReg(PPC::X1)
.addReg(PPC::X0);
}
// Add callee saved registers to move list.
const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
for (unsigned I = 0, E = CSI.size(); I != E; ++I) {
- int Offset = MFI->getObjectOffset(CSI[I].getFrameIdx());
unsigned Reg = CSI[I].getReg();
if (Reg == PPC::LR || Reg == PPC::LR8 || Reg == PPC::RM) continue;
+
+ // This is a bit of a hack: CR2LT, CR2GT, CR2EQ and CR2UN are just
+ // subregisters of CR2. We just need to emit a move of CR2.
+ if (PPC::CRBITRCRegClass.contains(Reg))
+ continue;
+
+ // For SVR4, don't emit a move for the CR spill slot if we haven't
+ // spilled CRs.
+ if (Subtarget.isSVR4ABI()
+ && (PPC::CR2 <= Reg && Reg <= PPC::CR4)
+ && !spillsCR(MF))
+ continue;
+
+ // For 64-bit SVR4 when we have spilled CRs, the spill location
+ // is SP+8, not a frame-relative slot.
+ if (Subtarget.isSVR4ABI()
+ && Subtarget.isPPC64()
+ && (PPC::CR2 <= Reg && Reg <= PPC::CR4)) {
+ MachineLocation CSDst(PPC::X1, 8);
+ MachineLocation CSSrc(PPC::CR2);
+ Moves.push_back(MachineMove(Label, CSDst, CSSrc));
+ continue;
+ }
+
+ int Offset = MFI->getObjectOffset(CSI[I].getFrameIdx());
MachineLocation CSDst(MachineLocation::VirtualFP, Offset);
MachineLocation CSSrc(Reg);
Moves.push_back(MachineMove(Label, CSDst, CSSrc));
void PPCFrameLowering::emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
- MachineBasicBlock::iterator MBBI = prior(MBB.end());
+ MachineBasicBlock::iterator MBBI = MBB.getLastNonDebugInstr();
+ assert(MBBI != MBB.end() && "Returning block has no terminator");
const PPCInstrInfo &TII =
*static_cast<const PPCInstrInfo*>(MF.getTarget().getInstrInfo());
// Callee pop calling convention. Pop parameter/linkage area. Used for tail
// call optimization
- if (GuaranteedTailCallOpt && RetOpcode == PPC::BLR &&
+ if (MF.getTarget().Options.GuaranteedTailCallOpt && RetOpcode == PPC::BLR &&
MF.getFunction()->getCallingConv() == CallingConv::Fast) {
PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
unsigned CallerAllocatedAmt = FI->getMinReservedArea();
.addReg(TmpReg);
}
} else if (RetOpcode == PPC::TCRETURNdi) {
- MBBI = prior(MBB.end());
+ MBBI = MBB.getLastNonDebugInstr();
MachineOperand &JumpTarget = MBBI->getOperand(0);
BuildMI(MBB, MBBI, dl, TII.get(PPC::TAILB)).
addGlobalAddress(JumpTarget.getGlobal(), JumpTarget.getOffset());
} else if (RetOpcode == PPC::TCRETURNri) {
- MBBI = prior(MBB.end());
+ MBBI = MBB.getLastNonDebugInstr();
assert(MBBI->getOperand(0).isReg() && "Expecting register operand.");
BuildMI(MBB, MBBI, dl, TII.get(PPC::TAILBCTR));
} else if (RetOpcode == PPC::TCRETURNai) {
- MBBI = prior(MBB.end());
+ MBBI = MBB.getLastNonDebugInstr();
MachineOperand &JumpTarget = MBBI->getOperand(0);
BuildMI(MBB, MBBI, dl, TII.get(PPC::TAILBA)).addImm(JumpTarget.getImm());
} else if (RetOpcode == PPC::TCRETURNdi8) {
- MBBI = prior(MBB.end());
+ MBBI = MBB.getLastNonDebugInstr();
MachineOperand &JumpTarget = MBBI->getOperand(0);
BuildMI(MBB, MBBI, dl, TII.get(PPC::TAILB8)).
addGlobalAddress(JumpTarget.getGlobal(), JumpTarget.getOffset());
} else if (RetOpcode == PPC::TCRETURNri8) {
- MBBI = prior(MBB.end());
+ MBBI = MBB.getLastNonDebugInstr();
assert(MBBI->getOperand(0).isReg() && "Expecting register operand.");
BuildMI(MBB, MBBI, dl, TII.get(PPC::TAILBCTR8));
} else if (RetOpcode == PPC::TCRETURNai8) {
- MBBI = prior(MBB.end());
+ MBBI = MBB.getLastNonDebugInstr();
MachineOperand &JumpTarget = MBBI->getOperand(0);
BuildMI(MBB, MBBI, dl, TII.get(PPC::TAILBA8)).addImm(JumpTarget.getImm());
}
}
-void PPCFrameLowering::getInitialFrameState(std::vector<MachineMove> &Moves) const {
- // Initial state of the frame pointer is R1.
- MachineLocation Dst(MachineLocation::VirtualFP);
- MachineLocation Src(PPC::R1, 0);
- Moves.push_back(MachineMove(0, Dst, Src));
-}
-
-static bool spillsCR(const MachineFunction &MF) {
- const PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>();
- return FuncInfo->isCRSpilled();
-}
-
/// MustSaveLR - Return true if this function requires that we save the LR
/// register onto the stack in the prolog and restore it in the epilog of the
/// function.
// Reserve stack space to move the linkage area to in case of a tail call.
int TCSPDelta = 0;
- if (GuaranteedTailCallOpt && (TCSPDelta = FI->getTailCallSPDelta()) < 0) {
+ if (MF.getTarget().Options.GuaranteedTailCallOpt &&
+ (TCSPDelta = FI->getTailCallSPDelta()) < 0) {
MFI->CreateFixedObject(-1 * TCSPDelta, TCSPDelta, true);
}
// FIXME: doesn't detect whether or not we need to spill vXX, which requires
// r0 for now.
- if (RegInfo->requiresRegisterScavenging(MF)) // FIXME (64-bit): Enable.
+ if (RegInfo->requiresRegisterScavenging(MF))
if (needsFP(MF) || spillsCR(MF)) {
const TargetRegisterClass *GPRC = &PPC::GPRCRegClass;
const TargetRegisterClass *G8RC = &PPC::G8RCRegClass;
bool HasGPSaveArea = false;
bool HasG8SaveArea = false;
bool HasFPSaveArea = false;
- bool HasCRSaveArea = false;
bool HasVRSAVESaveArea = false;
bool HasVRSaveArea = false;
for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
unsigned Reg = CSI[i].getReg();
- if (PPC::GPRCRegisterClass->contains(Reg)) {
+ if (PPC::GPRCRegClass.contains(Reg)) {
HasGPSaveArea = true;
GPRegs.push_back(CSI[i]);
if (Reg < MinGPR) {
MinGPR = Reg;
}
- } else if (PPC::G8RCRegisterClass->contains(Reg)) {
+ } else if (PPC::G8RCRegClass.contains(Reg)) {
HasG8SaveArea = true;
G8Regs.push_back(CSI[i]);
if (Reg < MinG8R) {
MinG8R = Reg;
}
- } else if (PPC::F8RCRegisterClass->contains(Reg)) {
+ } else if (PPC::F8RCRegClass.contains(Reg)) {
HasFPSaveArea = true;
FPRegs.push_back(CSI[i]);
if (Reg < MinFPR) {
MinFPR = Reg;
}
-// FIXME SVR4: Disable CR save area for now.
- } else if (PPC::CRBITRCRegisterClass->contains(Reg)
- || PPC::CRRCRegisterClass->contains(Reg)) {
-// HasCRSaveArea = true;
- } else if (PPC::VRSAVERCRegisterClass->contains(Reg)) {
+ } else if (PPC::CRBITRCRegClass.contains(Reg) ||
+ PPC::CRRCRegClass.contains(Reg)) {
+ ; // do nothing, as we already know whether CRs are spilled
+ } else if (PPC::VRSAVERCRegClass.contains(Reg)) {
HasVRSAVESaveArea = true;
- } else if (PPC::VRRCRegisterClass->contains(Reg)) {
+ } else if (PPC::VRRCRegClass.contains(Reg)) {
HasVRSaveArea = true;
VRegs.push_back(CSI[i]);
// Take into account stack space reserved for tail calls.
int TCSPDelta = 0;
- if (GuaranteedTailCallOpt && (TCSPDelta = PFI->getTailCallSPDelta()) < 0) {
+ if (MF.getTarget().Options.GuaranteedTailCallOpt &&
+ (TCSPDelta = PFI->getTailCallSPDelta()) < 0) {
LowerBound = TCSPDelta;
}
FFI->setObjectOffset(FI, LowerBound + FFI->getObjectOffset(FI));
}
- LowerBound -= (31 - PPCRegisterInfo::getRegisterNumbering(MinFPR) + 1) * 8;
+ LowerBound -= (31 - getPPCRegisterNumbering(MinFPR) + 1) * 8;
}
// Check whether the frame pointer register is allocated. If so, make sure it
}
unsigned MinReg =
- std::min<unsigned>(PPCRegisterInfo::getRegisterNumbering(MinGPR),
- PPCRegisterInfo::getRegisterNumbering(MinG8R));
+ std::min<unsigned>(getPPCRegisterNumbering(MinGPR),
+ getPPCRegisterNumbering(MinG8R));
if (Subtarget.isPPC64()) {
LowerBound -= (31 - MinReg + 1) * 8;
}
}
- // The CR save area is below the general register save area.
- if (HasCRSaveArea) {
- // FIXME SVR4: Is it actually possible to have multiple elements in CSI
- // which have the CR/CRBIT register class?
+ // For 32-bit only, the CR save area is below the general register
+ // save area. For 64-bit SVR4, the CR save area is addressed relative
+ // to the stack pointer and hence does not need an adjustment here.
+ // Only CR2 (the first nonvolatile spilled) has an associated frame
+ // index so that we have a single uniform save area.
+ if (spillsCR(MF) && !(Subtarget.isPPC64() && Subtarget.isSVR4ABI())) {
// Adjust the frame index of the CR spill slot.
for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
unsigned Reg = CSI[i].getReg();
- if (PPC::CRBITRCRegisterClass->contains(Reg) ||
- PPC::CRRCRegisterClass->contains(Reg)) {
+ if ((Subtarget.isSVR4ABI() && Reg == PPC::CR2)
+ // Leave Darwin logic as-is.
+ || (!Subtarget.isSVR4ABI() &&
+ (PPC::CRBITRCRegClass.contains(Reg) ||
+ PPC::CRRCRegClass.contains(Reg)))) {
int FI = CSI[i].getFrameIdx();
FFI->setObjectOffset(FI, LowerBound + FFI->getObjectOffset(FI));
for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
unsigned Reg = CSI[i].getReg();
- if (PPC::VRSAVERCRegisterClass->contains(Reg)) {
+ if (PPC::VRSAVERCRegClass.contains(Reg)) {
int FI = CSI[i].getFrameIdx();
FFI->setObjectOffset(FI, LowerBound + FFI->getObjectOffset(FI));
}
}
}
+
+bool
+PPCFrameLowering::spillCalleeSavedRegisters(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI,
+ const std::vector<CalleeSavedInfo> &CSI,
+ const TargetRegisterInfo *TRI) const {
+
+ // Currently, this function only handles SVR4 32- and 64-bit ABIs.
+ // Return false otherwise to maintain pre-existing behavior.
+ if (!Subtarget.isSVR4ABI())
+ return false;
+
+ MachineFunction *MF = MBB.getParent();
+ const PPCInstrInfo &TII =
+ *static_cast<const PPCInstrInfo*>(MF->getTarget().getInstrInfo());
+ DebugLoc DL;
+ bool CRSpilled = false;
+
+ for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
+ unsigned Reg = CSI[i].getReg();
+ // CR2 through CR4 are the nonvolatile CR fields.
+ bool IsCRField = PPC::CR2 <= Reg && Reg <= PPC::CR4;
+
+ if (CRSpilled && IsCRField)
+ continue;
+
+ // Add the callee-saved register as live-in; it's killed at the spill.
+ MBB.addLiveIn(Reg);
+
+ // Insert the spill to the stack frame.
+ if (IsCRField) {
+ CRSpilled = true;
+ // The first time we see a CR field, store the whole CR into the
+ // save slot via GPR12 (available in the prolog for 32- and 64-bit).
+ if (Subtarget.isPPC64()) {
+ // 64-bit: SP+8
+ MBB.insert(MI, BuildMI(*MF, DL, TII.get(PPC::MFCR), PPC::X12));
+ MBB.insert(MI, BuildMI(*MF, DL, TII.get(PPC::STW))
+ .addReg(PPC::X12,
+ getKillRegState(true))
+ .addImm(8)
+ .addReg(PPC::X1));
+ } else {
+ // 32-bit: FP-relative. Note that we made sure CR2-CR4 all have
+ // the same frame index in PPCRegisterInfo::hasReservedSpillSlot.
+ MBB.insert(MI, BuildMI(*MF, DL, TII.get(PPC::MFCR), PPC::R12));
+ MBB.insert(MI, addFrameReference(BuildMI(*MF, DL, TII.get(PPC::STW))
+ .addReg(PPC::R12,
+ getKillRegState(true)),
+ CSI[i].getFrameIdx()));
+ }
+
+ // Record that we spill the CR in this function.
+ PPCFunctionInfo *FuncInfo = MF->getInfo<PPCFunctionInfo>();
+ FuncInfo->setSpillsCR();
+ } else {
+ const TargetRegisterClass *RC = TRI->getMinimalPhysRegClass(Reg);
+ TII.storeRegToStackSlot(MBB, MI, Reg, true,
+ CSI[i].getFrameIdx(), RC, TRI);
+ }
+ }
+ return true;
+}
+
+static void
+restoreCRs(bool isPPC64, bool CR2Spilled, bool CR3Spilled, bool CR4Spilled,
+ MachineBasicBlock &MBB, MachineBasicBlock::iterator MI,
+ const std::vector<CalleeSavedInfo> &CSI, unsigned CSIIndex) {
+
+ MachineFunction *MF = MBB.getParent();
+ const PPCInstrInfo &TII =
+ *static_cast<const PPCInstrInfo*>(MF->getTarget().getInstrInfo());
+ DebugLoc DL;
+ unsigned RestoreOp, MoveReg;
+
+ if (isPPC64) {
+ // 64-bit: SP+8
+ MBB.insert(MI, BuildMI(*MF, DL, TII.get(PPC::LWZ), PPC::X12)
+ .addImm(8)
+ .addReg(PPC::X1));
+ RestoreOp = PPC::MTCRF8;
+ MoveReg = PPC::X12;
+ } else {
+ // 32-bit: FP-relative
+ MBB.insert(MI, addFrameReference(BuildMI(*MF, DL, TII.get(PPC::LWZ),
+ PPC::R12),
+ CSI[CSIIndex].getFrameIdx()));
+ RestoreOp = PPC::MTCRF;
+ MoveReg = PPC::R12;
+ }
+
+ if (CR2Spilled)
+ MBB.insert(MI, BuildMI(*MF, DL, TII.get(RestoreOp), PPC::CR2)
+ .addReg(MoveReg));
+
+ if (CR3Spilled)
+ MBB.insert(MI, BuildMI(*MF, DL, TII.get(RestoreOp), PPC::CR3)
+ .addReg(MoveReg));
+
+ if (CR4Spilled)
+ MBB.insert(MI, BuildMI(*MF, DL, TII.get(RestoreOp), PPC::CR4)
+ .addReg(MoveReg));
+}
+
+bool
+PPCFrameLowering::restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI,
+ const std::vector<CalleeSavedInfo> &CSI,
+ const TargetRegisterInfo *TRI) const {
+
+ // Currently, this function only handles SVR4 32- and 64-bit ABIs.
+ // Return false otherwise to maintain pre-existing behavior.
+ if (!Subtarget.isSVR4ABI())
+ return false;
+
+ MachineFunction *MF = MBB.getParent();
+ const PPCInstrInfo &TII =
+ *static_cast<const PPCInstrInfo*>(MF->getTarget().getInstrInfo());
+ bool CR2Spilled = false;
+ bool CR3Spilled = false;
+ bool CR4Spilled = false;
+ unsigned CSIIndex = 0;
+
+ // Initialize insertion-point logic; we will be restoring in reverse
+ // order of spill.
+ MachineBasicBlock::iterator I = MI, BeforeI = I;
+ bool AtStart = I == MBB.begin();
+
+ if (!AtStart)
+ --BeforeI;
+
+ for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
+ unsigned Reg = CSI[i].getReg();
+
+ if (Reg == PPC::CR2) {
+ CR2Spilled = true;
+ // The spill slot is associated only with CR2, which is the
+ // first nonvolatile spilled. Save it here.
+ CSIIndex = i;
+ continue;
+ } else if (Reg == PPC::CR3) {
+ CR3Spilled = true;
+ continue;
+ } else if (Reg == PPC::CR4) {
+ CR4Spilled = true;
+ continue;
+ } else {
+ // When we first encounter a non-CR register after seeing at
+ // least one CR register, restore all spilled CRs together.
+ if ((CR2Spilled || CR3Spilled || CR4Spilled)
+ && !(PPC::CR2 <= Reg && Reg <= PPC::CR4)) {
+ restoreCRs(Subtarget.isPPC64(), CR2Spilled, CR3Spilled, CR4Spilled,
+ MBB, I, CSI, CSIIndex);
+ CR2Spilled = CR3Spilled = CR4Spilled = false;
+ }
+
+ // Default behavior for non-CR saves.
+ const TargetRegisterClass *RC = TRI->getMinimalPhysRegClass(Reg);
+ TII.loadRegFromStackSlot(MBB, I, Reg, CSI[i].getFrameIdx(),
+ RC, TRI);
+ assert(I != MBB.begin() &&
+ "loadRegFromStackSlot didn't insert any code!");
+ }
+
+ // Insert in reverse order.
+ if (AtStart)
+ I = MBB.begin();
+ else {
+ I = BeforeI;
+ ++I;
+ }
+ }
+
+ // If we haven't yet spilled the CRs, do so now.
+ if (CR2Spilled || CR3Spilled || CR4Spilled)
+ restoreCRs(Subtarget.isPPC64(), CR2Spilled, CR3Spilled, CR4Spilled,
+ MBB, I, CSI, CSIIndex);
+
+ return true;
+}
+
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