-//======- Thumb1FrameLowering.cpp - Thumb1 Frame Information ---*- C++ -*-====//
+//===-- Thumb1FrameLowering.cpp - Thumb1 Frame Information ----------------===//
//
// The LLVM Compiler Infrastructure
//
//===----------------------------------------------------------------------===//
#include "Thumb1FrameLowering.h"
-#include "ARMBaseInstrInfo.h"
#include "ARMMachineFunctionInfo.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
using namespace llvm;
-bool Thumb1FrameLowering::hasReservedCallFrame(const MachineFunction &MF) const {
+bool Thumb1FrameLowering::hasReservedCallFrame(const 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
return !MF.getFrameInfo()->hasVarSizedObjects();
}
-static void emitSPUpdate(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator &MBBI,
- const TargetInstrInfo &TII, DebugLoc dl,
- const Thumb1RegisterInfo &MRI,
- int NumBytes) {
- emitThumbRegPlusImmediate(MBB, MBBI, ARM::SP, ARM::SP, NumBytes, TII,
- MRI, dl);
+static void
+emitSPUpdate(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &MBBI,
+ const TargetInstrInfo &TII, DebugLoc dl,
+ const Thumb1RegisterInfo &MRI,
+ int NumBytes, unsigned MIFlags = MachineInstr::NoFlags) {
+ emitThumbRegPlusImmediate(MBB, MBBI, dl, ARM::SP, ARM::SP, NumBytes, TII,
+ MRI, MIFlags);
}
void Thumb1FrameLowering::emitPrologue(MachineFunction &MF) const {
int FramePtrSpillFI = 0;
if (VARegSaveSize)
- emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -VARegSaveSize);
+ emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -VARegSaveSize,
+ MachineInstr::FrameSetup);
if (!AFI->hasStackFrame()) {
if (NumBytes != 0)
- emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -NumBytes);
+ emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -NumBytes,
+ MachineInstr::FrameSetup);
return;
}
case ARM::R11:
if (Reg == FramePtr)
FramePtrSpillFI = FI;
- if (STI.isTargetDarwin()) {
+ if (STI.isTargetIOS()) {
AFI->addGPRCalleeSavedArea2Frame(FI);
GPRCS2Size += 4;
} else {
// Adjust FP so it point to the stack slot that contains the previous FP.
if (hasFP(MF)) {
- BuildMI(MBB, MBBI, dl, TII.get(ARM::tADDrSPi), FramePtr)
- .addFrameIndex(FramePtrSpillFI).addImm(0);
- if (NumBytes > 7)
- // If offset is > 7 then sp cannot be adjusted in a single instruction,
+ AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tADDrSPi), FramePtr)
+ .addFrameIndex(FramePtrSpillFI).addImm(0)
+ .setMIFlags(MachineInstr::FrameSetup));
+ if (NumBytes > 508)
+ // If offset is > 508 then sp cannot be adjusted in a single instruction,
// try restoring from fp instead.
AFI->setShouldRestoreSPFromFP(true);
}
if (NumBytes)
// Insert it after all the callee-save spills.
- emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -NumBytes);
+ emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -NumBytes,
+ MachineInstr::FrameSetup);
if (STI.isTargetELF() && hasFP(MF))
MFI->setOffsetAdjustment(MFI->getOffsetAdjustment() -
AFI->setGPRCalleeSavedArea2Size(GPRCS2Size);
AFI->setDPRCalleeSavedAreaSize(DPRCSSize);
+ // Thumb1 does not currently support dynamic stack realignment. Report a
+ // fatal error rather then silently generate bad code.
+ if (RegInfo->needsStackRealignment(MF))
+ report_fatal_error("Dynamic stack realignment not supported for thumb1.");
+
// If we need a base pointer, set it up here. It's whatever the value
// of the stack pointer is at this point. Any variable size objects
// will be allocated after this, so we can still use the base pointer
// to reference locals.
if (RegInfo->hasBasePointer(MF))
- BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVgpr2gpr), BasePtr).addReg(ARM::SP);
+ AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr), BasePtr)
+ .addReg(ARM::SP));
+
+ // If the frame has variable sized objects then the epilogue must restore
+ // the sp from fp. We can assume there's an FP here since hasFP already
+ // checks for hasVarSizedObjects.
+ if (MFI->hasVarSizedObjects())
+ AFI->setShouldRestoreSPFromFP(true);
}
-static bool isCalleeSavedRegister(unsigned Reg, const unsigned *CSRegs) {
+static bool isCalleeSavedRegister(unsigned Reg, const uint16_t *CSRegs) {
for (unsigned i = 0; CSRegs[i]; ++i)
if (Reg == CSRegs[i])
return true;
return false;
}
-static bool isCSRestore(MachineInstr *MI, const unsigned *CSRegs) {
- if (MI->getOpcode() == ARM::tRestore &&
+static bool isCSRestore(MachineInstr *MI, const uint16_t *CSRegs) {
+ if (MI->getOpcode() == ARM::tLDRspi &&
MI->getOperand(1).isFI() &&
isCalleeSavedRegister(MI->getOperand(0).getReg(), CSRegs))
return true;
void Thumb1FrameLowering::emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
- MachineBasicBlock::iterator MBBI = prior(MBB.end());
+ MachineBasicBlock::iterator MBBI = MBB.getLastNonDebugInstr();
assert((MBBI->getOpcode() == ARM::tBX_RET ||
MBBI->getOpcode() == ARM::tPOP_RET) &&
"Can only insert epilog into returning blocks");
unsigned VARegSaveSize = AFI->getVarArgsRegSaveSize();
int NumBytes = (int)MFI->getStackSize();
- const unsigned *CSRegs = RegInfo->getCalleeSavedRegs();
+ const uint16_t *CSRegs = RegInfo->getCalleeSavedRegs();
unsigned FramePtr = RegInfo->getFrameRegister(MF);
if (!AFI->hasStackFrame()) {
if (AFI->shouldRestoreSPFromFP()) {
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.
+ // frame pointer stack slot, the target is ELF and the function has FP, or
+ // the target uses var sized objects.
if (NumBytes) {
assert(MF.getRegInfo().isPhysRegUsed(ARM::R4) &&
"No scratch register to restore SP from FP!");
- emitThumbRegPlusImmediate(MBB, MBBI, ARM::R4, FramePtr, -NumBytes,
- TII, *RegInfo, dl);
- BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVtgpr2gpr), ARM::SP)
- .addReg(ARM::R4);
+ emitThumbRegPlusImmediate(MBB, MBBI, dl, ARM::R4, FramePtr, -NumBytes,
+ TII, *RegInfo);
+ AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr),
+ ARM::SP)
+ .addReg(ARM::R4));
} else
- BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVtgpr2gpr), ARM::SP)
- .addReg(FramePtr);
+ AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr),
+ ARM::SP)
+ .addReg(FramePtr));
} else {
if (MBBI->getOpcode() == ARM::tBX_RET &&
&MBB.front() != MBBI &&
emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, VARegSaveSize);
- BuildMI(MBB, MBBI, dl, TII.get(ARM::tBX_RET_vararg))
+ MachineInstrBuilder MIB =
+ BuildMI(MBB, MBBI, dl, TII.get(ARM::tBX_RET_vararg))
.addReg(ARM::R3, RegState::Kill);
+ AddDefaultPred(MIB);
+ MIB->copyImplicitOps(&*MBBI);
// erase the old tBX_RET instruction
MBB.erase(MBBI);
}
MIB.addReg(Reg, getKillRegState(isKill));
}
+ MIB.setMIFlags(MachineInstr::FrameSetup);
return true;
}
continue;
Reg = ARM::PC;
(*MIB).setDesc(TII.get(ARM::tPOP_RET));
+ MIB->copyImplicitOps(&*MI);
MI = MBB.erase(MI);
}
MIB.addReg(Reg, getDefRegState(true));