#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/Support/ErrorHandling.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetMachine.h"
bool SeenSuperDef = false;
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
const MachineOperand &MO = MI->getOperand(i);
- if (!MO.isReg())
+ if (!MO.isReg() || MO.isUndef())
continue;
if (TRI->isSuperRegister(SubReg, MO.getReg())) {
if (MO.isUse())
return RedefinesSuperRegPart(MI, MO.getReg(), TRI);
}
+bool RegScavenger::isSuperRegUsed(unsigned Reg) const {
+ for (const unsigned *SuperRegs = TRI->getSuperRegisters(Reg);
+ unsigned SuperReg = *SuperRegs; ++SuperRegs)
+ if (isUsed(SuperReg))
+ return true;
+ return false;
+}
+
/// setUsed - Set the register and its sub-registers as being used.
-void RegScavenger::setUsed(unsigned Reg, bool ImpDef) {
+void RegScavenger::setUsed(unsigned Reg) {
RegsAvailable.reset(Reg);
- ImplicitDefed[Reg] = ImpDef;
for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
- unsigned SubReg = *SubRegs; ++SubRegs) {
+ unsigned SubReg = *SubRegs; ++SubRegs)
RegsAvailable.reset(SubReg);
- ImplicitDefed[SubReg] = ImpDef;
- }
}
/// setUnused - Set the register and its sub-registers as being unused.
void RegScavenger::setUnused(unsigned Reg, const MachineInstr *MI) {
RegsAvailable.set(Reg);
- ImplicitDefed.reset(Reg);
for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
unsigned SubReg = *SubRegs; ++SubRegs)
- if (!RedefinesSuperRegPart(MI, Reg, TRI)) {
+ if (!RedefinesSuperRegPart(MI, Reg, TRI))
RegsAvailable.set(SubReg);
- ImplicitDefed.reset(SubReg);
- }
}
void RegScavenger::enterBasicBlock(MachineBasicBlock *mbb) {
if (!MBB) {
NumPhysRegs = TRI->getNumRegs();
RegsAvailable.resize(NumPhysRegs);
- ImplicitDefed.resize(NumPhysRegs);
// Create reserved registers bitvector.
ReservedRegs = TRI->getReservedRegs(MF);
ScavengeRestore = NULL;
CurrDist = 0;
DistanceMap.clear();
- ImplicitDefed.reset();
// All registers started out unused.
RegsAvailable.set();
SmallPtrSet<MachineInstr*, 4> UsesInMBB;
for (MachineRegisterInfo::use_iterator UI = MRI->use_begin(Reg),
UE = MRI->use_end(); UI != UE; ++UI) {
+ MachineOperand &UseMO = UI.getOperand();
+ if (UseMO.isReg() && UseMO.isUndef())
+ continue;
MachineInstr *UseMI = &*UI;
if (UseMI->getParent() == MBB)
UsesInMBB.insert(UseMI);
ScavengeRestore = NULL;
}
- bool IsImpDef = MI->getOpcode() == TargetInstrInfo::IMPLICIT_DEF;
+#if 0
+ if (MI->getOpcode() == TargetInstrInfo::IMPLICIT_DEF)
+ return;
+#endif
// Separate register operands into 3 classes: uses, defs, earlyclobbers.
SmallVector<std::pair<const MachineOperand*,unsigned>, 4> UseMOs;
SmallVector<std::pair<const MachineOperand*,unsigned>, 4> EarlyClobberMOs;
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
const MachineOperand &MO = MI->getOperand(i);
- if (!MO.isReg() || MO.getReg() == 0)
+ if (!MO.isReg() || MO.getReg() == 0 || MO.isUndef())
continue;
if (MO.isUse())
UseMOs.push_back(std::make_pair(&MO,i));
const MachineOperand MO = *UseMOs[i].first;
unsigned Reg = MO.getReg();
- assert(isUsed(Reg) && "Using an undefined register!");
+ assert((MO.isImplicit() || isUsed(Reg)) && "Using an undefined register!");
- // Kill of implicit_def defined registers are ignored. e.g.
- // entry: 0x2029ab8, LLVM BB @0x1b06080, ID#0:
- // Live Ins: %R0
- // %R0<def> = IMPLICIT_DEF
- // %R0<def> = IMPLICIT_DEF
- // STR %R0<kill>, %R0, %reg0, 0, 14, %reg0, Mem:ST(4,4) [0x1b06510 + 0]
- // %R1<def> = LDR %R0, %reg0, 24, 14, %reg0, Mem:LD(4,4) [0x1b065bc + 0]
- if (MO.isKill() && !isReserved(Reg) && !isImplicitlyDefined(Reg)) {
+ if (MO.isKill() && !isReserved(Reg)) {
KillRegs.set(Reg);
// Mark sub-registers as used.
unsigned Idx = (i < NumECs)
? EarlyClobberMOs[i].second : DefMOs[i-NumECs].second;
unsigned Reg = MO.getReg();
+ if (MO.isUndef())
+ continue;
// If it's dead upon def, then it is now free.
if (MO.isDead()) {
}
// Skip two-address destination operand.
- if (MI->isRegTiedToUseOperand(Idx)) {
+ unsigned UseIdx;
+ if (MI->isRegTiedToUseOperand(Idx, &UseIdx) &&
+ !MI->getOperand(UseIdx).isUndef()) {
assert(isUsed(Reg) && "Using an undefined register!");
continue;
}
// Implicit def is allowed to "re-define" any register. Similarly,
// implicitly defined registers can be clobbered.
- assert((isReserved(Reg) || isUnused(Reg) ||
- IsImpDef || isImplicitlyDefined(Reg) ||
+ assert((MO.isImplicit() || isReserved(Reg) || isUnused(Reg) ||
+ isSuperRegUsed(Reg) ||
isLiveInButUnusedBefore(Reg, MI, MBB, TRI, MRI)) &&
"Re-defining a live register!");
- setUsed(Reg, IsImpDef);
+ setUsed(Reg);
}
}
SmallVector<std::pair<const MachineOperand*,unsigned>, 4> EarlyClobberMOs;
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
const MachineOperand &MO = MI->getOperand(i);
- if (!MO.isReg() || MO.getReg() == 0)
+ if (!MO.isReg() || MO.getReg() == 0 || MO.isUndef())
continue;
if (MO.isUse())
UseMOs.push_back(std::make_pair(&MO,i));
? *DefMOs[i].first : *EarlyClobberMOs[i-NumDefs].first;
unsigned Idx = (i < NumECs)
? DefMOs[i].second : EarlyClobberMOs[i-NumDefs].second;
+ if (MO.isUndef())
+ continue;
// Skip two-address destination operand.
if (MI->isRegTiedToUseOperand(Idx))
// Mask off the registers which are not in the TargetRegisterClass.
BitVector Candidates(NumPhysRegs, false);
CreateRegClassMask(RC, Candidates);
- Candidates ^= ReservedRegs; // Do not include reserved registers.
+ Candidates ^= ReservedRegs & Candidates; // Do not include reserved registers.
// Exclude all the registers being used by the instruction.
for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
Reg = Candidates.find_next(Reg);
}
- if (ScavengedReg != 0) {
- assert(0 && "Scavenger slot is live, unable to scavenge another register!");
- abort();
+ assert(ScavengedReg == 0 &&
+ "Scavenger slot is live, unable to scavenge another register!");
+
+ // Make sure SReg is marked as used. It could be considered available if it is
+ // one of the callee saved registers, but hasn't been spilled.
+ if (!isUsed(SReg)) {
+ MBB->addLiveIn(SReg);
+ setUsed(SReg);
}
// Spill the scavenged register before I.