-//=====- 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;
-// FIXME This disables some code that aligns the stack to a boundary bigger than
-// the default (16 bytes on Darwin) when there is a stack local of greater
-// alignment. This does not currently work, because the delta between old and
-// new stack pointers is added to offsets that reference incoming parameters
-// after the prolog is generated, and the code that does that doesn't handle a
-// variable delta. You don't want to do that anyway; a better approach is to
-// reserve another register that retains to the incoming stack pointer, and
-// reference parameters relative to that.
-#define ALIGN_STACK 0
-
-
/// 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;
// transform this into the appropriate ORI instruction.
static void HandleVRSaveUpdate(MachineInstr *MI, const TargetInstrInfo &TII) {
MachineFunction *MF = MI->getParent()->getParent();
+ const TargetRegisterInfo *TRI = MF->getTarget().getRegisterInfo();
DebugLoc dl = MI->getDebugLoc();
unsigned UsedRegMask = 0;
for (MachineRegisterInfo::livein_iterator
I = MF->getRegInfo().livein_begin(),
E = MF->getRegInfo().livein_end(); I != E; ++I) {
- unsigned RegNo = getPPCRegisterNumbering(I->first);
+ unsigned RegNo = TRI->getEncodingValue(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 = getPPCRegisterNumbering(*I);
- if (VRRegNo[RegNo] == *I) // If this really is a vector reg.
- UsedRegMask &= ~(1 << (31-RegNo)); // Doesn't need to be marked.
+
+ // Live out registers appear as use operands on return instructions.
+ for (MachineFunction::const_iterator BI = MF->begin(), BE = MF->end();
+ UsedRegMask != 0 && BI != BE; ++BI) {
+ const MachineBasicBlock &MBB = *BI;
+ if (MBB.empty() || !MBB.back().isReturn())
+ continue;
+ const MachineInstr &Ret = MBB.back();
+ for (unsigned I = 0, E = Ret.getNumOperands(); I != E; ++I) {
+ const MachineOperand &MO = Ret.getOperand(I);
+ if (!MO.isReg() || !PPC::VRRCRegClass.contains(MO.getReg()))
+ continue;
+ unsigned RegNo = TRI->getEncodingValue(MO.getReg());
+ UsedRegMask &= ~(1 << (31-RegNo));
+ }
}
// If no registers are used, turn this into a copy.
MI->eraseFromParent();
}
+static bool spillsCR(const MachineFunction &MF) {
+ const PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>();
+ return FuncInfo->isCRSpilled();
+}
+
+static bool spillsVRSAVE(const MachineFunction &MF) {
+ const PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>();
+ return FuncInfo->isVRSAVESpilled();
+}
+
+static bool hasSpills(const MachineFunction &MF) {
+ const PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>();
+ return FuncInfo->hasSpills();
+}
+
+static bool hasNonRISpills(const MachineFunction &MF) {
+ const PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>();
+ return FuncInfo->hasNonRISpills();
+}
+
/// determineFrameLayout - Determine the size of the frame and maximum call
/// frame size.
-void PPCFrameLowering::determineFrameLayout(MachineFunction &MF) const {
+unsigned PPCFrameLowering::determineFrameLayout(MachineFunction &MF,
+ bool UpdateMF,
+ bool UseEstimate) const {
MachineFrameInfo *MFI = MF.getFrameInfo();
// Get the number of bytes to allocate from the FrameInfo
- unsigned FrameSize = MFI->getStackSize();
+ unsigned FrameSize =
+ UseEstimate ? MFI->estimateStackSize(MF) : MFI->getStackSize();
- // Get the alignments provided by the target, and the maximum alignment
- // (if any) of the fixed frame objects.
- unsigned MaxAlign = MFI->getMaxAlignment();
- unsigned TargetAlign = getStackAlignment();
- unsigned AlignMask = TargetAlign - 1; //
+ // Get stack alignments. The frame must be aligned to the greatest of these:
+ unsigned TargetAlign = getStackAlignment(); // alignment required per the ABI
+ unsigned MaxAlign = MFI->getMaxAlignment(); // algmt required by data in frame
+ unsigned AlignMask = std::max(MaxAlign, TargetAlign) - 1;
+
+ const PPCRegisterInfo *RegInfo =
+ static_cast<const PPCRegisterInfo*>(MF.getTarget().getRegisterInfo());
// 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.
+ // The 32-bit SVR4 ABI has no Red Zone. However, it can still generate
+ // stackless code if all local vars are reg-allocated.
+ bool DisableRedZone = MF.getFunction()->getAttributes().
+ hasAttribute(AttributeSet::FunctionIndex, Attribute::NoRedZone);
if (!DisableRedZone &&
+ (Subtarget.isPPC64() || // 32-bit SVR4, no stack-
+ !Subtarget.isSVR4ABI() || // allocated locals.
+ FrameSize == 0) &&
FrameSize <= 224 && // Fits in red zone.
!MFI->hasVarSizedObjects() && // No dynamic alloca.
!MFI->adjustsStack() && // No calls.
- (!ALIGN_STACK || MaxAlign <= TargetAlign)) { // No special alignment.
+ !RegInfo->hasBasePointer(MF)) { // No special alignment.
// No need for frame
- MFI->setStackSize(0);
- return;
+ if (UpdateMF)
+ MFI->setStackSize(0);
+ return 0;
}
// Get the maximum call frame size of all the calls.
maxCallFrameSize = (maxCallFrameSize + AlignMask) & ~AlignMask;
// Update maximum call frame size.
- MFI->setMaxCallFrameSize(maxCallFrameSize);
+ if (UpdateMF)
+ MFI->setMaxCallFrameSize(maxCallFrameSize);
// Include call frame size in total.
FrameSize += maxCallFrameSize;
FrameSize = (FrameSize + AlignMask) & ~AlignMask;
// Update frame info.
- MFI->setStackSize(FrameSize);
+ if (UpdateMF)
+ MFI->setStackSize(FrameSize);
+
+ return FrameSize;
}
// hasFP - Return true if the specified function actually has a dedicated frame
// 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 MF.getTarget().Options.DisableFramePointerElim(MF) ||
MF.getInfo<PPCFunctionInfo>()->hasFastCall());
}
+void PPCFrameLowering::replaceFPWithRealFP(MachineFunction &MF) const {
+ bool is31 = needsFP(MF);
+ unsigned FPReg = is31 ? PPC::R31 : PPC::R1;
+ unsigned FP8Reg = is31 ? PPC::X31 : PPC::X1;
+
+ const PPCRegisterInfo *RegInfo =
+ static_cast<const PPCRegisterInfo*>(MF.getTarget().getRegisterInfo());
+ bool HasBP = RegInfo->hasBasePointer(MF);
+ unsigned BPReg = HasBP ? (unsigned) PPC::R30 : FPReg;
+ unsigned BP8Reg = HasBP ? (unsigned) PPC::X30 : FPReg;
+
+ for (MachineFunction::iterator BI = MF.begin(), BE = MF.end();
+ BI != BE; ++BI)
+ for (MachineBasicBlock::iterator MBBI = BI->end(); MBBI != BI->begin(); ) {
+ --MBBI;
+ for (unsigned I = 0, E = MBBI->getNumOperands(); I != E; ++I) {
+ MachineOperand &MO = MBBI->getOperand(I);
+ if (!MO.isReg())
+ continue;
+
+ switch (MO.getReg()) {
+ case PPC::FP:
+ MO.setReg(FPReg);
+ break;
+ case PPC::FP8:
+ MO.setReg(FP8Reg);
+ break;
+ case PPC::BP:
+ MO.setReg(BPReg);
+ break;
+ case PPC::BP8:
+ MO.setReg(BP8Reg);
+ break;
+
+ }
+ }
+ }
+}
void PPCFrameLowering::emitPrologue(MachineFunction &MF) const {
MachineBasicBlock &MBB = MF.front(); // Prolog goes in entry BB
MachineFrameInfo *MFI = MF.getFrameInfo();
const PPCInstrInfo &TII =
*static_cast<const PPCInstrInfo*>(MF.getTarget().getInstrInfo());
+ const PPCRegisterInfo *RegInfo =
+ static_cast<const PPCRegisterInfo*>(MF.getTarget().getRegisterInfo());
MachineModuleInfo &MMI = MF.getMMI();
+ const MCRegisterInfo *MRI = MMI.getContext().getRegisterInfo();
DebugLoc dl;
bool needsFrameMoves = MMI.hasDebugInfo() ||
MF.getFunction()->needsUnwindTableEntry();
- // Prepare for frame info.
- MCSymbol *FrameLabel = 0;
+ // Get processor type.
+ bool isPPC64 = Subtarget.isPPC64();
+ // Get the ABI.
+ bool isDarwinABI = Subtarget.isDarwinABI();
+ bool isSVR4ABI = Subtarget.isSVR4ABI();
+ assert((isDarwinABI || isSVR4ABI) &&
+ "Currently only Darwin and SVR4 ABIs are supported for PowerPC.");
// 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 (!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();
// Work out frame sizes.
- // FIXME: determineFrameLayout() may change the frame size. This should be
- // moved upper, to some hook.
- determineFrameLayout(MF);
- unsigned FrameSize = MFI->getStackSize();
-
+ unsigned FrameSize = determineFrameLayout(MF);
int NegFrameSize = -FrameSize;
+ if (!isInt<32>(NegFrameSize))
+ llvm_unreachable("Unhandled stack size!");
+
+ if (MFI->isFrameAddressTaken())
+ replaceFPWithRealFP(MF);
- // Get processor type.
- bool isPPC64 = Subtarget.isPPC64();
- // Get operating system
- bool isDarwinABI = Subtarget.isDarwinABI();
// Check if the link register (LR) must be saved.
PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
bool MustSaveLR = FI->mustSaveLR();
- // Do we have a frame pointer for this function?
+ const SmallVectorImpl<unsigned> &MustSaveCRs = FI->getMustSaveCRs();
+ // Do we have a frame pointer and/or base pointer for this function?
bool HasFP = hasFP(MF);
+ bool HasBP = RegInfo->hasBasePointer(MF);
+
+ unsigned SPReg = isPPC64 ? PPC::X1 : PPC::R1;
+ unsigned BPReg = isPPC64 ? PPC::X30 : PPC::R30;
+ unsigned FPReg = isPPC64 ? PPC::X31 : PPC::R31;
+ unsigned LRReg = isPPC64 ? PPC::LR8 : PPC::LR;
+ unsigned ScratchReg = isPPC64 ? PPC::X0 : PPC::R0;
+ unsigned TempReg = isPPC64 ? PPC::X12 : PPC::R12; // another scratch reg
+ // ...(R12/X12 is volatile in both Darwin & SVR4, & can't be a function arg.)
+ const MCInstrDesc& MFLRInst = TII.get(isPPC64 ? PPC::MFLR8
+ : PPC::MFLR );
+ const MCInstrDesc& StoreInst = TII.get(isPPC64 ? PPC::STD
+ : PPC::STW );
+ const MCInstrDesc& StoreUpdtInst = TII.get(isPPC64 ? PPC::STDU
+ : PPC::STWU );
+ const MCInstrDesc& StoreUpdtIdxInst = TII.get(isPPC64 ? PPC::STDUX
+ : PPC::STWUX);
+ const MCInstrDesc& LoadImmShiftedInst = TII.get(isPPC64 ? PPC::LIS8
+ : PPC::LIS );
+ const MCInstrDesc& OrImmInst = TII.get(isPPC64 ? PPC::ORI8
+ : PPC::ORI );
+ const MCInstrDesc& OrInst = TII.get(isPPC64 ? PPC::OR8
+ : PPC::OR );
+ const MCInstrDesc& SubtractCarryingInst = TII.get(isPPC64 ? PPC::SUBFC8
+ : PPC::SUBFC);
+ const MCInstrDesc& SubtractImmCarryingInst = TII.get(isPPC64 ? PPC::SUBFIC8
+ : PPC::SUBFIC);
+
+ // Regarding this assert: Even though LR is saved in the caller's frame (i.e.,
+ // LROffset is positive), that slot is callee-owned. Because PPC32 SVR4 has no
+ // Red Zone, an asynchronous event (a form of "callee") could claim a frame &
+ // overwrite it, so PPC32 SVR4 must claim at least a minimal frame to save LR.
+ assert((isPPC64 || !isSVR4ABI || !(!FrameSize && (MustSaveLR || HasFP))) &&
+ "FrameSize must be >0 to save/restore the FP or LR for 32-bit SVR4.");
int LROffset = PPCFrameLowering::getReturnSaveOffset(isPPC64, isDarwinABI);
int FPOffset = 0;
if (HasFP) {
- if (Subtarget.isSVR4ABI()) {
+ if (isSVR4ABI) {
MachineFrameInfo *FFI = MF.getFrameInfo();
int FPIndex = FI->getFramePointerSaveIndex();
assert(FPIndex && "No Frame Pointer Save Slot!");
}
}
- if (isPPC64) {
- if (MustSaveLR)
- BuildMI(MBB, MBBI, dl, TII.get(PPC::MFLR8), PPC::X0);
+ int BPOffset = 0;
+ if (HasBP) {
+ if (isSVR4ABI) {
+ MachineFrameInfo *FFI = MF.getFrameInfo();
+ int BPIndex = FI->getBasePointerSaveIndex();
+ assert(BPIndex && "No Base Pointer Save Slot!");
+ BPOffset = FFI->getObjectOffset(BPIndex);
+ } else {
+ BPOffset =
+ PPCFrameLowering::getBasePointerSaveOffset(isPPC64, isDarwinABI);
+ }
+ }
+
+ // Get stack alignments.
+ unsigned MaxAlign = MFI->getMaxAlignment();
+ if (HasBP && MaxAlign > 1)
+ assert(isPowerOf2_32(MaxAlign) && isInt<16>(MaxAlign) &&
+ "Invalid alignment!");
- if (HasFP)
- BuildMI(MBB, MBBI, dl, TII.get(PPC::STD))
- .addReg(PPC::X31)
- .addImm(FPOffset/4)
- .addReg(PPC::X1);
+ // Frames of 32KB & larger require special handling because they cannot be
+ // indexed into with a simple STDU/STWU/STD/STW immediate offset operand.
+ bool isLargeFrame = !isInt<16>(NegFrameSize);
- if (MustSaveLR)
- BuildMI(MBB, MBBI, dl, TII.get(PPC::STD))
- .addReg(PPC::X0)
- .addImm(LROffset / 4)
- .addReg(PPC::X1);
- } else {
- if (MustSaveLR)
- BuildMI(MBB, MBBI, dl, TII.get(PPC::MFLR), PPC::R0);
+ if (MustSaveLR)
+ BuildMI(MBB, MBBI, dl, MFLRInst, ScratchReg);
- if (HasFP)
- BuildMI(MBB, MBBI, dl, TII.get(PPC::STW))
- .addReg(PPC::R31)
- .addImm(FPOffset)
- .addReg(PPC::R1);
+ assert((isPPC64 || MustSaveCRs.empty()) &&
+ "Prologue CR saving supported only in 64-bit mode");
- if (MustSaveLR)
- BuildMI(MBB, MBBI, dl, TII.get(PPC::STW))
- .addReg(PPC::R0)
- .addImm(LROffset)
- .addReg(PPC::R1);
+ if (!MustSaveCRs.empty()) { // will only occur for PPC64
+ MachineInstrBuilder MIB =
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::MFCR8), TempReg);
+ for (unsigned i = 0, e = MustSaveCRs.size(); i != e; ++i)
+ MIB.addReg(MustSaveCRs[i], RegState::ImplicitKill);
}
- // Skip if a leaf routine.
+ if (HasFP)
+ // FIXME: On PPC32 SVR4, we must not spill before claiming the stackframe.
+ BuildMI(MBB, MBBI, dl, StoreInst)
+ .addReg(FPReg)
+ .addImm(FPOffset)
+ .addReg(SPReg);
+
+ if (HasBP)
+ // FIXME: On PPC32 SVR4, we must not spill before claiming the stackframe.
+ BuildMI(MBB, MBBI, dl, StoreInst)
+ .addReg(BPReg)
+ .addImm(BPOffset)
+ .addReg(SPReg);
+
+ if (MustSaveLR)
+ // FIXME: On PPC32 SVR4, we must not spill before claiming the stackframe.
+ BuildMI(MBB, MBBI, dl, StoreInst)
+ .addReg(ScratchReg)
+ .addImm(LROffset)
+ .addReg(SPReg);
+
+ if (!MustSaveCRs.empty()) // will only occur for PPC64
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::STW8))
+ .addReg(TempReg, getKillRegState(true))
+ .addImm(8)
+ .addReg(SPReg);
+
+ // Skip the rest if this is a leaf function & all spills fit in the Red Zone.
if (!FrameSize) return;
- // Get stack alignments.
- unsigned TargetAlign = getStackAlignment();
- unsigned MaxAlign = MFI->getMaxAlignment();
-
// Adjust stack pointer: r1 += NegFrameSize.
// If there is a preferred stack alignment, align R1 now
- if (!isPPC64) {
- // PPC32.
- if (ALIGN_STACK && MaxAlign > TargetAlign) {
- assert(isPowerOf2_32(MaxAlign) && isInt<16>(MaxAlign) &&
- "Invalid alignment!");
- assert(isInt<16>(NegFrameSize) && "Unhandled stack size and alignment!");
-
- BuildMI(MBB, MBBI, dl, TII.get(PPC::RLWINM), PPC::R0)
- .addReg(PPC::R1)
+
+ if (HasBP) {
+ // Save a copy of r1 as the base pointer.
+ BuildMI(MBB, MBBI, dl, OrInst, BPReg)
+ .addReg(SPReg)
+ .addReg(SPReg);
+ }
+
+ if (HasBP && MaxAlign > 1) {
+ if (isPPC64)
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::RLDICL), ScratchReg)
+ .addReg(SPReg)
+ .addImm(0)
+ .addImm(64 - Log2_32(MaxAlign));
+ else // PPC32...
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::RLWINM), ScratchReg)
+ .addReg(SPReg)
.addImm(0)
.addImm(32 - Log2_32(MaxAlign))
.addImm(31);
- 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)
- .addReg(PPC::R1)
- .addReg(PPC::R0);
- } else if (isInt<16>(NegFrameSize)) {
- BuildMI(MBB, MBBI, dl, TII.get(PPC::STWU), PPC::R1)
- .addReg(PPC::R1)
- .addImm(NegFrameSize)
- .addReg(PPC::R1);
- } else {
- BuildMI(MBB, MBBI, dl, TII.get(PPC::LIS), PPC::R0)
- .addImm(NegFrameSize >> 16);
- 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)
- .addReg(PPC::R1)
- .addReg(PPC::R0);
- }
- } else { // PPC64.
- if (ALIGN_STACK && MaxAlign > TargetAlign) {
- assert(isPowerOf2_32(MaxAlign) && isInt<16>(MaxAlign) &&
- "Invalid alignment!");
- assert(isInt<16>(NegFrameSize) && "Unhandled stack size and alignment!");
-
- BuildMI(MBB, MBBI, dl, TII.get(PPC::RLDICL), PPC::X0)
- .addReg(PPC::X1)
- .addImm(0)
- .addImm(64 - Log2_32(MaxAlign));
- BuildMI(MBB, MBBI, dl, TII.get(PPC::SUBFIC8), PPC::X0)
- .addReg(PPC::X0)
+ if (!isLargeFrame) {
+ BuildMI(MBB, MBBI, dl, SubtractImmCarryingInst, ScratchReg)
+ .addReg(ScratchReg, RegState::Kill)
.addImm(NegFrameSize);
- BuildMI(MBB, MBBI, dl, TII.get(PPC::STDUX))
- .addReg(PPC::X1)
- .addReg(PPC::X1)
- .addReg(PPC::X0);
- } else if (isInt<16>(NegFrameSize)) {
- BuildMI(MBB, MBBI, dl, TII.get(PPC::STDU), PPC::X1)
- .addReg(PPC::X1)
- .addImm(NegFrameSize / 4)
- .addReg(PPC::X1);
} else {
- BuildMI(MBB, MBBI, dl, TII.get(PPC::LIS8), PPC::X0)
+ BuildMI(MBB, MBBI, dl, LoadImmShiftedInst, TempReg)
.addImm(NegFrameSize >> 16);
- BuildMI(MBB, MBBI, dl, TII.get(PPC::ORI8), PPC::X0)
- .addReg(PPC::X0, RegState::Kill)
+ BuildMI(MBB, MBBI, dl, OrImmInst, TempReg)
+ .addReg(TempReg, RegState::Kill)
.addImm(NegFrameSize & 0xFFFF);
- BuildMI(MBB, MBBI, dl, TII.get(PPC::STDUX))
- .addReg(PPC::X1)
- .addReg(PPC::X1)
- .addReg(PPC::X0);
+ BuildMI(MBB, MBBI, dl, SubtractCarryingInst, ScratchReg)
+ .addReg(ScratchReg, RegState::Kill)
+ .addReg(TempReg, RegState::Kill);
}
- }
+ BuildMI(MBB, MBBI, dl, StoreUpdtIdxInst, SPReg)
+ .addReg(SPReg, RegState::Kill)
+ .addReg(SPReg)
+ .addReg(ScratchReg);
- std::vector<MachineMove> &Moves = MMI.getFrameMoves();
+ } else if (!isLargeFrame) {
+ BuildMI(MBB, MBBI, dl, StoreUpdtInst, SPReg)
+ .addReg(SPReg)
+ .addImm(NegFrameSize)
+ .addReg(SPReg);
+
+ } else {
+ BuildMI(MBB, MBBI, dl, LoadImmShiftedInst, ScratchReg)
+ .addImm(NegFrameSize >> 16);
+ BuildMI(MBB, MBBI, dl, OrImmInst, ScratchReg)
+ .addReg(ScratchReg, RegState::Kill)
+ .addImm(NegFrameSize & 0xFFFF);
+ BuildMI(MBB, MBBI, dl, StoreUpdtIdxInst, SPReg)
+ .addReg(SPReg, RegState::Kill)
+ .addReg(SPReg)
+ .addReg(ScratchReg);
+ }
// Add the "machine moves" for the instructions we generated above, but in
// reverse order.
if (needsFrameMoves) {
- // Mark effective beginning of when frame pointer becomes valid.
- FrameLabel = MMI.getContext().CreateTempSymbol();
- BuildMI(MBB, MBBI, dl, TII.get(PPC::PROLOG_LABEL)).addSym(FrameLabel);
-
// Show update of SP.
- if (NegFrameSize) {
- MachineLocation SPDst(MachineLocation::VirtualFP);
- MachineLocation SPSrc(MachineLocation::VirtualFP, NegFrameSize);
- Moves.push_back(MachineMove(FrameLabel, SPDst, SPSrc));
- } else {
- MachineLocation SP(isPPC64 ? PPC::X31 : PPC::R31);
- Moves.push_back(MachineMove(FrameLabel, SP, SP));
- }
+ assert(NegFrameSize);
+ unsigned CFIIndex = MMI.addFrameInst(
+ MCCFIInstruction::createDefCfaOffset(nullptr, NegFrameSize));
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::CFI_INSTRUCTION)).addCFIIndex(CFIIndex);
if (HasFP) {
- MachineLocation FPDst(MachineLocation::VirtualFP, FPOffset);
- MachineLocation FPSrc(isPPC64 ? PPC::X31 : PPC::R31);
- Moves.push_back(MachineMove(FrameLabel, FPDst, FPSrc));
+ unsigned Reg = MRI->getDwarfRegNum(FPReg, true);
+ CFIIndex = MMI.addFrameInst(
+ MCCFIInstruction::createOffset(nullptr, Reg, FPOffset));
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::CFI_INSTRUCTION))
+ .addCFIIndex(CFIIndex);
+ }
+
+ if (HasBP) {
+ unsigned Reg = MRI->getDwarfRegNum(BPReg, true);
+ CFIIndex = MMI.addFrameInst(
+ MCCFIInstruction::createOffset(nullptr, Reg, BPOffset));
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::CFI_INSTRUCTION))
+ .addCFIIndex(CFIIndex);
}
if (MustSaveLR) {
- MachineLocation LRDst(MachineLocation::VirtualFP, LROffset);
- MachineLocation LRSrc(isPPC64 ? PPC::LR8 : PPC::LR);
- Moves.push_back(MachineMove(FrameLabel, LRDst, LRSrc));
+ unsigned Reg = MRI->getDwarfRegNum(LRReg, true);
+ CFIIndex = MMI.addFrameInst(
+ MCCFIInstruction::createOffset(nullptr, Reg, LROffset));
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::CFI_INSTRUCTION))
+ .addCFIIndex(CFIIndex);
}
}
- MCSymbol *ReadyLabel = 0;
-
// If there is a frame pointer, copy R1 into R31
if (HasFP) {
- if (!isPPC64) {
- BuildMI(MBB, MBBI, dl, TII.get(PPC::OR), PPC::R31)
- .addReg(PPC::R1)
- .addReg(PPC::R1);
- } else {
- BuildMI(MBB, MBBI, dl, TII.get(PPC::OR8), PPC::X31)
- .addReg(PPC::X1)
- .addReg(PPC::X1);
- }
+ BuildMI(MBB, MBBI, dl, OrInst, FPReg)
+ .addReg(SPReg)
+ .addReg(SPReg);
if (needsFrameMoves) {
- ReadyLabel = MMI.getContext().CreateTempSymbol();
-
// Mark effective beginning of when frame pointer is ready.
- BuildMI(MBB, MBBI, dl, TII.get(PPC::PROLOG_LABEL)).addSym(ReadyLabel);
+ unsigned Reg = MRI->getDwarfRegNum(FPReg, true);
+ unsigned CFIIndex = MMI.addFrameInst(
+ MCCFIInstruction::createDefCfaRegister(nullptr, Reg));
- MachineLocation FPDst(HasFP ? (isPPC64 ? PPC::X31 : PPC::R31) :
- (isPPC64 ? PPC::X1 : PPC::R1));
- MachineLocation FPSrc(MachineLocation::VirtualFP);
- Moves.push_back(MachineMove(ReadyLabel, FPDst, FPSrc));
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::CFI_INSTRUCTION))
+ .addCFIIndex(CFIIndex);
}
}
if (needsFrameMoves) {
- MCSymbol *Label = HasFP ? ReadyLabel : FrameLabel;
-
// 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::CRBITRCRegisterClass->contains(Reg))
+ if (PPC::CRBITRCRegClass.contains(Reg))
continue;
- MachineLocation CSDst(MachineLocation::VirtualFP, Offset);
- MachineLocation CSSrc(Reg);
- Moves.push_back(MachineMove(Label, CSDst, CSSrc));
+ // For SVR4, don't emit a move for the CR spill slot if we haven't
+ // spilled CRs.
+ if (isSVR4ABI && (PPC::CR2 <= Reg && Reg <= PPC::CR4)
+ && MustSaveCRs.empty())
+ continue;
+
+ // For 64-bit SVR4 when we have spilled CRs, the spill location
+ // is SP+8, not a frame-relative slot.
+ if (isSVR4ABI && isPPC64 && (PPC::CR2 <= Reg && Reg <= PPC::CR4)) {
+ unsigned CFIIndex = MMI.addFrameInst(MCCFIInstruction::createOffset(
+ nullptr, MRI->getDwarfRegNum(PPC::CR2, true), 8));
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::CFI_INSTRUCTION))
+ .addCFIIndex(CFIIndex);
+ continue;
+ }
+
+ int Offset = MFI->getObjectOffset(CSI[I].getFrameIdx());
+ unsigned CFIIndex = MMI.addFrameInst(MCCFIInstruction::createOffset(
+ nullptr, MRI->getDwarfRegNum(Reg, true), Offset));
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::CFI_INSTRUCTION))
+ .addCFIIndex(CFIIndex);
}
}
}
assert(MBBI != MBB.end() && "Returning block has no terminator");
const PPCInstrInfo &TII =
*static_cast<const PPCInstrInfo*>(MF.getTarget().getInstrInfo());
+ const PPCRegisterInfo *RegInfo =
+ static_cast<const PPCRegisterInfo*>(MF.getTarget().getRegisterInfo());
unsigned RetOpcode = MBBI->getOpcode();
DebugLoc dl;
RetOpcode == PPC::TCRETURNai8) &&
"Can only insert epilog into returning blocks");
- // Get alignment info so we know how to restore r1
+ // Get alignment info so we know how to restore the SP.
const MachineFrameInfo *MFI = MF.getFrameInfo();
- unsigned TargetAlign = getStackAlignment();
- unsigned MaxAlign = MFI->getMaxAlignment();
// Get the number of bytes allocated from the FrameInfo.
int FrameSize = MFI->getStackSize();
// Get processor type.
bool isPPC64 = Subtarget.isPPC64();
- // Get operating system
+ // Get the ABI.
bool isDarwinABI = Subtarget.isDarwinABI();
+ bool isSVR4ABI = Subtarget.isSVR4ABI();
+
// Check if the link register (LR) has been saved.
PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
bool MustSaveLR = FI->mustSaveLR();
- // Do we have a frame pointer for this function?
+ const SmallVectorImpl<unsigned> &MustSaveCRs = FI->getMustSaveCRs();
+ // Do we have a frame pointer and/or base pointer for this function?
bool HasFP = hasFP(MF);
+ bool HasBP = RegInfo->hasBasePointer(MF);
+
+ unsigned SPReg = isPPC64 ? PPC::X1 : PPC::R1;
+ unsigned BPReg = isPPC64 ? PPC::X30 : PPC::R30;
+ unsigned FPReg = isPPC64 ? PPC::X31 : PPC::R31;
+ unsigned ScratchReg = isPPC64 ? PPC::X0 : PPC::R0;
+ unsigned TempReg = isPPC64 ? PPC::X12 : PPC::R12; // another scratch reg
+ const MCInstrDesc& MTLRInst = TII.get( isPPC64 ? PPC::MTLR8
+ : PPC::MTLR );
+ const MCInstrDesc& LoadInst = TII.get( isPPC64 ? PPC::LD
+ : PPC::LWZ );
+ const MCInstrDesc& LoadImmShiftedInst = TII.get( isPPC64 ? PPC::LIS8
+ : PPC::LIS );
+ const MCInstrDesc& OrImmInst = TII.get( isPPC64 ? PPC::ORI8
+ : PPC::ORI );
+ const MCInstrDesc& AddImmInst = TII.get( isPPC64 ? PPC::ADDI8
+ : PPC::ADDI );
+ const MCInstrDesc& AddInst = TII.get( isPPC64 ? PPC::ADD8
+ : PPC::ADD4 );
int LROffset = PPCFrameLowering::getReturnSaveOffset(isPPC64, isDarwinABI);
int FPOffset = 0;
if (HasFP) {
- if (Subtarget.isSVR4ABI()) {
+ if (isSVR4ABI) {
MachineFrameInfo *FFI = MF.getFrameInfo();
int FPIndex = FI->getFramePointerSaveIndex();
assert(FPIndex && "No Frame Pointer Save Slot!");
}
}
+ int BPOffset = 0;
+ if (HasBP) {
+ if (isSVR4ABI) {
+ MachineFrameInfo *FFI = MF.getFrameInfo();
+ int BPIndex = FI->getBasePointerSaveIndex();
+ assert(BPIndex && "No Base Pointer Save Slot!");
+ BPOffset = FFI->getObjectOffset(BPIndex);
+ } else {
+ BPOffset =
+ PPCFrameLowering::getBasePointerSaveOffset(isPPC64, isDarwinABI);
+ }
+ }
+
bool UsesTCRet = RetOpcode == PPC::TCRETURNri ||
RetOpcode == PPC::TCRETURNdi ||
RetOpcode == PPC::TCRETURNai ||
FrameSize += StackAdj;
}
+ // Frames of 32KB & larger require special handling because they cannot be
+ // indexed into with a simple LD/LWZ immediate offset operand.
+ bool isLargeFrame = !isInt<16>(FrameSize);
+
if (FrameSize) {
- // The loaded (or persistent) stack pointer value is offset by the 'stwu'
- // on entry to the function. Add this offset back now.
- if (!isPPC64) {
- // If this function contained a fastcc call and GuaranteedTailCallOpt is
- // enabled (=> hasFastCall()==true) the fastcc call might contain a tail
- // call which invalidates the stack pointer value in SP(0). So we use the
- // value of R31 in this case.
- if (FI->hasFastCall() && isInt<16>(FrameSize)) {
- assert(hasFP(MF) && "Expecting a valid the frame pointer.");
- BuildMI(MBB, MBBI, dl, TII.get(PPC::ADDI), PPC::R1)
- .addReg(PPC::R31).addImm(FrameSize);
- } else if(FI->hasFastCall()) {
- BuildMI(MBB, MBBI, dl, TII.get(PPC::LIS), PPC::R0)
- .addImm(FrameSize >> 16);
- BuildMI(MBB, MBBI, dl, TII.get(PPC::ORI), PPC::R0)
- .addReg(PPC::R0, RegState::Kill)
- .addImm(FrameSize & 0xFFFF);
- BuildMI(MBB, MBBI, dl, TII.get(PPC::ADD4))
- .addReg(PPC::R1)
- .addReg(PPC::R31)
- .addReg(PPC::R0);
- } else if (isInt<16>(FrameSize) &&
- (!ALIGN_STACK || TargetAlign >= MaxAlign) &&
- !MFI->hasVarSizedObjects()) {
- BuildMI(MBB, MBBI, dl, TII.get(PPC::ADDI), PPC::R1)
- .addReg(PPC::R1).addImm(FrameSize);
+ // In the prologue, the loaded (or persistent) stack pointer value is offset
+ // by the STDU/STDUX/STWU/STWUX instruction. Add this offset back now.
+
+ // If this function contained a fastcc call and GuaranteedTailCallOpt is
+ // enabled (=> hasFastCall()==true) the fastcc call might contain a tail
+ // call which invalidates the stack pointer value in SP(0). So we use the
+ // value of R31 in this case.
+ if (FI->hasFastCall()) {
+ assert(HasFP && "Expecting a valid frame pointer.");
+ if (!isLargeFrame) {
+ BuildMI(MBB, MBBI, dl, AddImmInst, SPReg)
+ .addReg(FPReg).addImm(FrameSize);
} else {
- BuildMI(MBB, MBBI, dl, TII.get(PPC::LWZ),PPC::R1)
- .addImm(0).addReg(PPC::R1);
- }
- } else {
- if (FI->hasFastCall() && isInt<16>(FrameSize)) {
- assert(hasFP(MF) && "Expecting a valid the frame pointer.");
- BuildMI(MBB, MBBI, dl, TII.get(PPC::ADDI8), PPC::X1)
- .addReg(PPC::X31).addImm(FrameSize);
- } else if(FI->hasFastCall()) {
- BuildMI(MBB, MBBI, dl, TII.get(PPC::LIS8), PPC::X0)
+ BuildMI(MBB, MBBI, dl, LoadImmShiftedInst, ScratchReg)
.addImm(FrameSize >> 16);
- BuildMI(MBB, MBBI, dl, TII.get(PPC::ORI8), PPC::X0)
- .addReg(PPC::X0, RegState::Kill)
+ BuildMI(MBB, MBBI, dl, OrImmInst, ScratchReg)
+ .addReg(ScratchReg, RegState::Kill)
.addImm(FrameSize & 0xFFFF);
- BuildMI(MBB, MBBI, dl, TII.get(PPC::ADD8))
- .addReg(PPC::X1)
- .addReg(PPC::X31)
- .addReg(PPC::X0);
- } else if (isInt<16>(FrameSize) && TargetAlign >= MaxAlign &&
- !MFI->hasVarSizedObjects()) {
- BuildMI(MBB, MBBI, dl, TII.get(PPC::ADDI8), PPC::X1)
- .addReg(PPC::X1).addImm(FrameSize);
- } else {
- BuildMI(MBB, MBBI, dl, TII.get(PPC::LD), PPC::X1)
- .addImm(0).addReg(PPC::X1);
+ BuildMI(MBB, MBBI, dl, AddInst)
+ .addReg(SPReg)
+ .addReg(FPReg)
+ .addReg(ScratchReg);
}
+ } else if (!isLargeFrame && !HasBP && !MFI->hasVarSizedObjects()) {
+ BuildMI(MBB, MBBI, dl, AddImmInst, SPReg)
+ .addReg(SPReg)
+ .addImm(FrameSize);
+ } else {
+ BuildMI(MBB, MBBI, dl, LoadInst, SPReg)
+ .addImm(0)
+ .addReg(SPReg);
}
+
}
- if (isPPC64) {
- if (MustSaveLR)
- BuildMI(MBB, MBBI, dl, TII.get(PPC::LD), PPC::X0)
- .addImm(LROffset/4).addReg(PPC::X1);
+ if (MustSaveLR)
+ BuildMI(MBB, MBBI, dl, LoadInst, ScratchReg)
+ .addImm(LROffset)
+ .addReg(SPReg);
- if (HasFP)
- BuildMI(MBB, MBBI, dl, TII.get(PPC::LD), PPC::X31)
- .addImm(FPOffset/4).addReg(PPC::X1);
+ assert((isPPC64 || MustSaveCRs.empty()) &&
+ "Epilogue CR restoring supported only in 64-bit mode");
- if (MustSaveLR)
- BuildMI(MBB, MBBI, dl, TII.get(PPC::MTLR8)).addReg(PPC::X0);
- } else {
- if (MustSaveLR)
- BuildMI(MBB, MBBI, dl, TII.get(PPC::LWZ), PPC::R0)
- .addImm(LROffset).addReg(PPC::R1);
+ if (!MustSaveCRs.empty()) // will only occur for PPC64
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::LWZ8), TempReg)
+ .addImm(8)
+ .addReg(SPReg);
- if (HasFP)
- BuildMI(MBB, MBBI, dl, TII.get(PPC::LWZ), PPC::R31)
- .addImm(FPOffset).addReg(PPC::R1);
+ if (HasFP)
+ BuildMI(MBB, MBBI, dl, LoadInst, FPReg)
+ .addImm(FPOffset)
+ .addReg(SPReg);
- if (MustSaveLR)
- BuildMI(MBB, MBBI, dl, TII.get(PPC::MTLR)).addReg(PPC::R0);
- }
+ if (HasBP)
+ BuildMI(MBB, MBBI, dl, LoadInst, BPReg)
+ .addImm(BPOffset)
+ .addReg(SPReg);
+
+ if (!MustSaveCRs.empty()) // will only occur for PPC64
+ for (unsigned i = 0, e = MustSaveCRs.size(); i != e; ++i)
+ BuildMI(MBB, MBBI, dl, TII.get(PPC::MTOCRF8), MustSaveCRs[i])
+ .addReg(TempReg, getKillRegState(i == e-1));
+
+ if (MustSaveLR)
+ BuildMI(MBB, MBBI, dl, MTLRInst).addReg(ScratchReg);
// Callee pop calling convention. Pop parameter/linkage area. Used for tail
// call optimization
MF.getFunction()->getCallingConv() == CallingConv::Fast) {
PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
unsigned CallerAllocatedAmt = FI->getMinReservedArea();
- unsigned StackReg = isPPC64 ? PPC::X1 : PPC::R1;
- unsigned FPReg = isPPC64 ? PPC::X31 : PPC::R31;
- unsigned TmpReg = isPPC64 ? PPC::X0 : PPC::R0;
- unsigned ADDIInstr = isPPC64 ? PPC::ADDI8 : PPC::ADDI;
- unsigned ADDInstr = isPPC64 ? PPC::ADD8 : PPC::ADD4;
- unsigned LISInstr = isPPC64 ? PPC::LIS8 : PPC::LIS;
- unsigned ORIInstr = isPPC64 ? PPC::ORI8 : PPC::ORI;
if (CallerAllocatedAmt && isInt<16>(CallerAllocatedAmt)) {
- BuildMI(MBB, MBBI, dl, TII.get(ADDIInstr), StackReg)
- .addReg(StackReg).addImm(CallerAllocatedAmt);
+ BuildMI(MBB, MBBI, dl, AddImmInst, SPReg)
+ .addReg(SPReg).addImm(CallerAllocatedAmt);
} else {
- BuildMI(MBB, MBBI, dl, TII.get(LISInstr), TmpReg)
+ BuildMI(MBB, MBBI, dl, LoadImmShiftedInst, ScratchReg)
.addImm(CallerAllocatedAmt >> 16);
- BuildMI(MBB, MBBI, dl, TII.get(ORIInstr), TmpReg)
- .addReg(TmpReg, RegState::Kill)
+ BuildMI(MBB, MBBI, dl, OrImmInst, ScratchReg)
+ .addReg(ScratchReg, RegState::Kill)
.addImm(CallerAllocatedAmt & 0xFFFF);
- BuildMI(MBB, MBBI, dl, TII.get(ADDInstr))
- .addReg(StackReg)
+ BuildMI(MBB, MBBI, dl, AddInst)
+ .addReg(SPReg)
.addReg(FPReg)
- .addReg(TmpReg);
+ .addReg(ScratchReg);
}
} else if (RetOpcode == PPC::TCRETURNdi) {
MBBI = MBB.getLastNonDebugInstr();
}
}
-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.
void
PPCFrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
- RegScavenger *RS) const {
- const TargetRegisterInfo *RegInfo = MF.getTarget().getRegisterInfo();
+ RegScavenger *) const {
+ const PPCRegisterInfo *RegInfo =
+ static_cast<const PPCRegisterInfo*>(MF.getTarget().getRegisterInfo());
// Save and clear the LR state.
PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
unsigned LR = RegInfo->getRARegister();
FI->setMustSaveLR(MustSaveLR(MF, LR));
- MF.getRegInfo().setPhysRegUnused(LR);
+ MachineRegisterInfo &MRI = MF.getRegInfo();
+ MRI.setPhysRegUnused(LR);
// Save R31 if necessary
int FPSI = FI->getFramePointerSaveIndex();
FI->setFramePointerSaveIndex(FPSI);
}
+ int BPSI = FI->getBasePointerSaveIndex();
+ if (!BPSI && RegInfo->hasBasePointer(MF)) {
+ int BPOffset = getBasePointerSaveOffset(isPPC64, isDarwinABI);
+ // Allocate the frame index for the base pointer save area.
+ BPSI = MFI->CreateFixedObject(isPPC64? 8 : 4, BPOffset, true);
+ // Save the result.
+ FI->setBasePointerSaveIndex(BPSI);
+ }
+
// Reserve stack space to move the linkage area to in case of a tail call.
int TCSPDelta = 0;
if (MF.getTarget().Options.GuaranteedTailCallOpt &&
MFI->CreateFixedObject(-1 * TCSPDelta, TCSPDelta, true);
}
- // Reserve a slot closest to SP or frame pointer if we have a dynalloc or
- // a large stack, which will require scavenging a register to materialize a
- // large offset.
- // FIXME: this doesn't actually check stack size, so is a bit pessimistic
- // FIXME: doesn't detect whether or not we need to spill vXX, which requires
- // r0 for now.
-
- if (RegInfo->requiresRegisterScavenging(MF))
- if (needsFP(MF) || spillsCR(MF)) {
- const TargetRegisterClass *GPRC = &PPC::GPRCRegClass;
- const TargetRegisterClass *G8RC = &PPC::G8RCRegClass;
- const TargetRegisterClass *RC = isPPC64 ? G8RC : GPRC;
- RS->setScavengingFrameIndex(MFI->CreateStackObject(RC->getSize(),
- RC->getAlignment(),
- false));
- }
+ // For 32-bit SVR4, allocate the nonvolatile CR spill slot iff the
+ // function uses CR 2, 3, or 4.
+ if (!isPPC64 && !isDarwinABI &&
+ (MRI.isPhysRegUsed(PPC::CR2) ||
+ MRI.isPhysRegUsed(PPC::CR3) ||
+ MRI.isPhysRegUsed(PPC::CR4))) {
+ int FrameIdx = MFI->CreateFixedObject((uint64_t)4, (int64_t)-4, true);
+ FI->setCRSpillFrameIndex(FrameIdx);
+ }
}
-void PPCFrameLowering::processFunctionBeforeFrameFinalized(MachineFunction &MF)
- const {
+void PPCFrameLowering::processFunctionBeforeFrameFinalized(MachineFunction &MF,
+ RegScavenger *RS) const {
// Early exit if not using the SVR4 ABI.
- if (!Subtarget.isSVR4ABI())
+ if (!Subtarget.isSVR4ABI()) {
+ addScavengingSpillSlot(MF, RS);
return;
+ }
// Get callee saved register information.
MachineFrameInfo *FFI = MF.getFrameInfo();
// Early exit if no callee saved registers are modified!
if (CSI.empty() && !needsFP(MF)) {
+ addScavengingSpillSlot(MF, RS);
return;
}
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]);
}
PPCFunctionInfo *PFI = MF.getInfo<PPCFunctionInfo>();
+ const TargetRegisterInfo *TRI = MF.getTarget().getRegisterInfo();
int64_t LowerBound = 0;
FFI->setObjectOffset(FI, LowerBound + FFI->getObjectOffset(FI));
}
- LowerBound -= (31 - getPPCRegisterNumbering(MinFPR) + 1) * 8;
+ LowerBound -= (31 - TRI->getEncodingValue(MinFPR) + 1) * 8;
}
// Check whether the frame pointer register is allocated. If so, make sure it
FFI->setObjectOffset(FI, LowerBound + FFI->getObjectOffset(FI));
}
+ const PPCRegisterInfo *RegInfo =
+ static_cast<const PPCRegisterInfo*>(MF.getTarget().getRegisterInfo());
+ if (RegInfo->hasBasePointer(MF)) {
+ HasGPSaveArea = true;
+
+ int FI = PFI->getBasePointerSaveIndex();
+ assert(FI && "No Base Pointer Save Slot!");
+
+ FFI->setObjectOffset(FI, LowerBound + FFI->getObjectOffset(FI));
+ }
+
// General register save area starts right below the Floating-point
// register save area.
if (HasGPSaveArea || HasG8SaveArea) {
}
unsigned MinReg =
- std::min<unsigned>(getPPCRegisterNumbering(MinGPR),
- getPPCRegisterNumbering(MinG8R));
+ std::min<unsigned>(TRI->getEncodingValue(MinGPR),
+ TRI->getEncodingValue(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));
FFI->setObjectOffset(FI, LowerBound + FFI->getObjectOffset(FI));
}
}
+
+ addScavengingSpillSlot(MF, RS);
+}
+
+void
+PPCFrameLowering::addScavengingSpillSlot(MachineFunction &MF,
+ RegScavenger *RS) const {
+ // Reserve a slot closest to SP or frame pointer if we have a dynalloc or
+ // a large stack, which will require scavenging a register to materialize a
+ // large offset.
+
+ // We need to have a scavenger spill slot for spills if the frame size is
+ // large. In case there is no free register for large-offset addressing,
+ // this slot is used for the necessary emergency spill. Also, we need the
+ // slot for dynamic stack allocations.
+
+ // The scavenger might be invoked if the frame offset does not fit into
+ // the 16-bit immediate. We don't know the complete frame size here
+ // because we've not yet computed callee-saved register spills or the
+ // needed alignment padding.
+ unsigned StackSize = determineFrameLayout(MF, false, true);
+ MachineFrameInfo *MFI = MF.getFrameInfo();
+ if (MFI->hasVarSizedObjects() || spillsCR(MF) || spillsVRSAVE(MF) ||
+ hasNonRISpills(MF) || (hasSpills(MF) && !isInt<16>(StackSize))) {
+ const TargetRegisterClass *GPRC = &PPC::GPRCRegClass;
+ const TargetRegisterClass *G8RC = &PPC::G8RCRegClass;
+ const TargetRegisterClass *RC = Subtarget.isPPC64() ? G8RC : GPRC;
+ RS->addScavengingFrameIndex(MFI->CreateStackObject(RC->getSize(),
+ RC->getAlignment(),
+ false));
+
+ // Might we have over-aligned allocas?
+ bool HasAlVars = MFI->hasVarSizedObjects() &&
+ MFI->getMaxAlignment() > getStackAlignment();
+
+ // These kinds of spills might need two registers.
+ if (spillsCR(MF) || spillsVRSAVE(MF) || HasAlVars)
+ RS->addScavengingFrameIndex(MFI->CreateStackObject(RC->getSize(),
+ RC->getAlignment(),
+ false));
+
+ }
+}
+
+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;
+ MachineInstrBuilder CRMIB;
+
+ for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
+ unsigned Reg = CSI[i].getReg();
+ // Only Darwin actually uses the VRSAVE register, but it can still appear
+ // here if, for example, @llvm.eh.unwind.init() is used. If we're not on
+ // Darwin, ignore it.
+ if (Reg == PPC::VRSAVE && !Subtarget.isDarwinABI())
+ continue;
+
+ // CR2 through CR4 are the nonvolatile CR fields.
+ bool IsCRField = PPC::CR2 <= Reg && Reg <= PPC::CR4;
+
+ // Add the callee-saved register as live-in; it's killed at the spill.
+ MBB.addLiveIn(Reg);
+
+ if (CRSpilled && IsCRField) {
+ CRMIB.addReg(Reg, RegState::ImplicitKill);
+ continue;
+ }
+
+ // Insert the spill to the stack frame.
+ if (IsCRField) {
+ PPCFunctionInfo *FuncInfo = MF->getInfo<PPCFunctionInfo>();
+ if (Subtarget.isPPC64()) {
+ // The actual spill will happen at the start of the prologue.
+ FuncInfo->addMustSaveCR(Reg);
+ } else {
+ CRSpilled = true;
+ FuncInfo->setSpillsCR();
+
+ // 32-bit: FP-relative. Note that we made sure CR2-CR4 all have
+ // the same frame index in PPCRegisterInfo::hasReservedSpillSlot.
+ CRMIB = BuildMI(*MF, DL, TII.get(PPC::MFCR), PPC::R12)
+ .addReg(Reg, RegState::ImplicitKill);
+
+ MBB.insert(MI, CRMIB);
+ MBB.insert(MI, addFrameReference(BuildMI(*MF, DL, TII.get(PPC::STW))
+ .addReg(PPC::R12,
+ getKillRegState(true)),
+ CSI[i].getFrameIdx()));
+ }
+ } 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 is31,
+ 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)
+ // This is handled during epilogue generation.
+ return;
+ else {
+ // 32-bit: FP-relative
+ MBB.insert(MI, addFrameReference(BuildMI(*MF, DL, TII.get(PPC::LWZ),
+ PPC::R12),
+ CSI[CSIIndex].getFrameIdx()));
+ RestoreOp = PPC::MTOCRF;
+ MoveReg = PPC::R12;
+ }
+
+ if (CR2Spilled)
+ MBB.insert(MI, BuildMI(*MF, DL, TII.get(RestoreOp), PPC::CR2)
+ .addReg(MoveReg, getKillRegState(!CR3Spilled && !CR4Spilled)));
+
+ if (CR3Spilled)
+ MBB.insert(MI, BuildMI(*MF, DL, TII.get(RestoreOp), PPC::CR3)
+ .addReg(MoveReg, getKillRegState(!CR4Spilled)));
+
+ if (CR4Spilled)
+ MBB.insert(MI, BuildMI(*MF, DL, TII.get(RestoreOp), PPC::CR4)
+ .addReg(MoveReg, getKillRegState(true)));
+}
+
+void PPCFrameLowering::
+eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator I) const {
+ const PPCInstrInfo &TII =
+ *static_cast<const PPCInstrInfo*>(MF.getTarget().getInstrInfo());
+ if (MF.getTarget().Options.GuaranteedTailCallOpt &&
+ I->getOpcode() == PPC::ADJCALLSTACKUP) {
+ // Add (actually subtract) back the amount the callee popped on return.
+ if (int CalleeAmt = I->getOperand(1).getImm()) {
+ bool is64Bit = Subtarget.isPPC64();
+ CalleeAmt *= -1;
+ unsigned StackReg = is64Bit ? PPC::X1 : PPC::R1;
+ unsigned TmpReg = is64Bit ? PPC::X0 : PPC::R0;
+ unsigned ADDIInstr = is64Bit ? PPC::ADDI8 : PPC::ADDI;
+ unsigned ADDInstr = is64Bit ? PPC::ADD8 : PPC::ADD4;
+ unsigned LISInstr = is64Bit ? PPC::LIS8 : PPC::LIS;
+ unsigned ORIInstr = is64Bit ? PPC::ORI8 : PPC::ORI;
+ MachineInstr *MI = I;
+ DebugLoc dl = MI->getDebugLoc();
+
+ if (isInt<16>(CalleeAmt)) {
+ BuildMI(MBB, I, dl, TII.get(ADDIInstr), StackReg)
+ .addReg(StackReg, RegState::Kill)
+ .addImm(CalleeAmt);
+ } else {
+ MachineBasicBlock::iterator MBBI = I;
+ BuildMI(MBB, MBBI, dl, TII.get(LISInstr), TmpReg)
+ .addImm(CalleeAmt >> 16);
+ BuildMI(MBB, MBBI, dl, TII.get(ORIInstr), TmpReg)
+ .addReg(TmpReg, RegState::Kill)
+ .addImm(CalleeAmt & 0xFFFF);
+ BuildMI(MBB, MBBI, dl, TII.get(ADDInstr), StackReg)
+ .addReg(StackReg, RegState::Kill)
+ .addReg(TmpReg);
+ }
+ }
+ }
+ // Simply discard ADJCALLSTACKDOWN, ADJCALLSTACKUP instructions.
+ MBB.erase(I);
+}
+
+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();
+
+ // Only Darwin actually uses the VRSAVE register, but it can still appear
+ // here if, for example, @llvm.eh.unwind.init() is used. If we're not on
+ // Darwin, ignore it.
+ if (Reg == PPC::VRSAVE && !Subtarget.isDarwinABI())
+ continue;
+
+ 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)) {
+ bool is31 = needsFP(*MF);
+ restoreCRs(Subtarget.isPPC64(), is31,
+ 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) {
+ bool is31 = needsFP(*MF);
+ restoreCRs(Subtarget.isPPC64(), is31, CR2Spilled, CR3Spilled, CR4Spilled,
+ MBB, I, CSI, CSIIndex);
+ }
+
+ return true;
}
+
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