-//===- Thumb1RegisterInfo.cpp - Thumb-1 Register Information -------*- C++ -*-===//
+//===- Thumb1RegisterInfo.cpp - Thumb-1 Register Information ----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
//
//===----------------------------------------------------------------------===//
//
-// This file contains the Thumb-1 implementation of the TargetRegisterInfo class.
+// This file contains the Thumb-1 implementation of the TargetRegisterInfo
+// class.
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
+extern cl::opt<bool> ReuseFrameIndexVals;
+
Thumb1RegisterInfo::Thumb1RegisterInfo(const ARMBaseInstrInfo &tii,
const ARMSubtarget &sti)
: ARMBaseRegisterInfo(tii, sti) {
return TargetRegisterInfo::getPhysicalRegisterRegClass(Reg, VT);
}
-bool
-Thumb1RegisterInfo::requiresRegisterScavenging(const MachineFunction &MF) const {
- return true;
-}
-
-bool
-Thumb1RegisterInfo::requiresFrameIndexScavenging(const MachineFunction &MF)
- const {
- return true;
-}
-
-
bool Thumb1RegisterInfo::hasReservedCallFrame(MachineFunction &MF) const {
const MachineFrameInfo *FFI = MF.getFrameInfo();
unsigned CFSize = FFI->getMaxCallFrameSize();
unsigned
Thumb1RegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
- int SPAdj, int *Value,
+ int SPAdj, FrameIndexValue *Value,
RegScavenger *RS) const{
unsigned VReg = 0;
unsigned i = 0;
Offset -= AFI->getGPRCalleeSavedArea1Offset();
else if (AFI->isGPRCalleeSavedArea2Frame(FrameIndex))
Offset -= AFI->getGPRCalleeSavedArea2Offset();
- else if (hasFP(MF)) {
- assert(SPAdj == 0 && "Unexpected");
- // There is alloca()'s in this function, must reference off the frame
+ else if (MF.getFrameInfo()->hasVarSizedObjects()) {
+ assert(SPAdj == 0 && hasFP(MF) && "Unexpected");
+ // There are alloca()'s in this function, must reference off the frame
// pointer instead.
FrameReg = getFrameRegister(MF);
Offset -= AFI->getFramePtrSpillOffset();
"Thumb add/sub sp, #imm immediate must be multiple of 4!");
}
- if (Offset == 0) {
+ unsigned PredReg;
+ if (Offset == 0 && getInstrPredicate(&MI, PredReg) == ARMCC::AL) {
// Turn it into a move.
MI.setDesc(TII.get(ARM::tMOVgpr2tgpr));
MI.getOperand(i).ChangeToRegister(FrameReg, false);
- MI.RemoveOperand(i+1);
+ // Remove offset and remaining explicit predicate operands.
+ do MI.RemoveOperand(i+1);
+ while (MI.getNumOperands() > i+1 &&
+ (!MI.getOperand(i+1).isReg() || !MI.getOperand(i+1).isImm()));
return 0;
}
MI.getOperand(i+1).ChangeToImmediate(Mask);
}
Offset = (Offset - Mask * Scale);
- MachineBasicBlock::iterator NII = next(II);
+ MachineBasicBlock::iterator NII = llvm::next(II);
emitThumbRegPlusImmediate(MBB, NII, DestReg, DestReg, Offset, TII,
*this, dl);
} else {
} else if (Desc.mayStore()) {
VReg = MF.getRegInfo().createVirtualRegister(ARM::tGPRRegisterClass);
assert (Value && "Frame index virtual allocated, but Value arg is NULL!");
- *Value = Offset;
bool UseRR = false;
+ bool TrackVReg = true;
+ Value->first = FrameReg; // use the frame register as a kind indicator
+ Value->second = Offset;
if (Opcode == ARM::tSpill) {
if (FrameReg == ARM::SP)
else {
emitLoadConstPool(MBB, II, dl, VReg, 0, Offset);
UseRR = true;
+ TrackVReg = false;
}
} else
emitThumbRegPlusImmediate(MBB, II, VReg, FrameReg, Offset, TII,
MI.addOperand(MachineOperand::CreateReg(FrameReg, false));
else // tSTR has an extra register operand.
MI.addOperand(MachineOperand::CreateReg(0, false));
+ if (!ReuseFrameIndexVals || !TrackVReg)
+ VReg = 0;
} else
assert(false && "Unexpected opcode!");
}
static bool isCSRestore(MachineInstr *MI, const unsigned *CSRegs) {
- return (MI->getOpcode() == ARM::tRestore &&
- MI->getOperand(1).isFI() &&
- isCalleeSavedRegister(MI->getOperand(0).getReg(), CSRegs));
+ if (MI->getOpcode() == ARM::tRestore &&
+ MI->getOperand(1).isFI() &&
+ isCalleeSavedRegister(MI->getOperand(0).getReg(), CSRegs))
+ return true;
+ else if (MI->getOpcode() == ARM::tPOP) {
+ // The first three operands are predicates and such. The last two are
+ // imp-def and imp-use of SP. Check everything in between.
+ for (int i = 3, e = MI->getNumOperands() - 2; i != e; ++i)
+ if (!isCalleeSavedRegister(MI->getOperand(i).getReg(), CSRegs))
+ return false;
+ return true;
+ }
+ return false;
}
void Thumb1RegisterInfo::emitEpilogue(MachineFunction &MF,
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
unsigned VARegSaveSize = AFI->getVarArgsRegSaveSize();
int NumBytes = (int)MFI->getStackSize();
+ const unsigned *CSRegs = getCalleeSavedRegs();
if (!AFI->hasStackFrame()) {
if (NumBytes != 0)
emitSPUpdate(MBB, MBBI, TII, dl, *this, NumBytes);
} else {
- // Unwind MBBI to point to first LDR / FLDD.
- const unsigned *CSRegs = getCalleeSavedRegs();
+ // Unwind MBBI to point to first LDR / VLDRD.
if (MBBI != MBB.begin()) {
do
--MBBI;
}
if (VARegSaveSize) {
+ // Unlike T2 and ARM mode, the T1 pop instruction cannot restore
+ // to LR, and we can't pop the value directly to the PC since
+ // we need to update the SP after popping the value. Therefore, we
+ // pop the old LR into R3 as a temporary.
+
+ // Move back past the callee-saved register restoration
+ while (MBBI != MBB.end() && isCSRestore(MBBI, CSRegs))
+ ++MBBI;
// Epilogue for vararg functions: pop LR to R3 and branch off it.
- // FIXME: Verify this is still ok when R3 is no longer being reserved.
AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tPOP)))
.addReg(0) // No write back.
.addReg(ARM::R3, RegState::Define);
BuildMI(MBB, MBBI, dl, TII.get(ARM::tBX_RET_vararg))
.addReg(ARM::R3, RegState::Kill);
+ // erase the old tBX_RET instruction
MBB.erase(MBBI);
}
}
projects / oota-llvm.git / blobdiff