// is spilled or split.
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "regalloc"
#include "llvm/CodeGen/LiveRangeEdit.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/CalcSpillWeights.h"
using namespace llvm;
+#define DEBUG_TYPE "regalloc"
+
STATISTIC(NumDCEDeleted, "Number of instructions deleted by DCE");
STATISTIC(NumDCEFoldedLoads, "Number of single use loads folded after DCE");
STATISTIC(NumFracRanges, "Number of live ranges fractured by DCE");
void LiveRangeEdit::Delegate::anchor() { }
-LiveInterval &LiveRangeEdit::createFrom(unsigned OldReg) {
+LiveInterval &LiveRangeEdit::createEmptyIntervalFrom(unsigned OldReg) {
unsigned VReg = MRI.createVirtualRegister(MRI.getRegClass(OldReg));
if (VRM) {
- VRM->grow();
VRM->setIsSplitFromReg(VReg, VRM->getOriginal(OldReg));
}
- LiveInterval &LI = LIS.getOrCreateInterval(VReg);
- NewRegs.push_back(&LI);
+ LiveInterval &LI = LIS.createEmptyInterval(VReg);
return LI;
}
+unsigned LiveRangeEdit::createFrom(unsigned OldReg) {
+ unsigned VReg = MRI.createVirtualRegister(MRI.getRegClass(OldReg));
+ if (VRM) {
+ VRM->setIsSplitFromReg(VReg, VRM->getOriginal(OldReg));
+ }
+ return VReg;
+}
+
bool LiveRangeEdit::checkRematerializable(VNInfo *VNI,
const MachineInstr *DefMI,
AliasAnalysis *aa) {
}
void LiveRangeEdit::scanRemattable(AliasAnalysis *aa) {
- for (LiveInterval::vni_iterator I = getParent().vni_begin(),
- E = getParent().vni_end(); I != E; ++I) {
- VNInfo *VNI = *I;
+ for (VNInfo *VNI : getParent().valnos) {
if (VNI->isUnused())
continue;
MachineInstr *DefMI = LIS.getInstructionFromIndex(VNI->def);
}
// If only cheap remats were requested, bail out early.
- if (cheapAsAMove && !RM.OrigMI->isAsCheapAsAMove())
+ if (cheapAsAMove && !TII.isAsCheapAsAMove(RM.OrigMI))
return false;
// Verify that all used registers are available with the same values.
bool LiveRangeEdit::foldAsLoad(LiveInterval *LI,
SmallVectorImpl<MachineInstr*> &Dead) {
- MachineInstr *DefMI = 0, *UseMI = 0;
+ MachineInstr *DefMI = nullptr, *UseMI = nullptr;
// Check that there is a single def and a single use.
- for (MachineRegisterInfo::reg_nodbg_iterator I = MRI.reg_nodbg_begin(LI->reg),
- E = MRI.reg_nodbg_end(); I != E; ++I) {
- MachineOperand &MO = I.getOperand();
+ for (MachineOperand &MO : MRI.reg_nodbg_operands(LI->reg)) {
MachineInstr *MI = MO.getParent();
if (MO.isDef()) {
if (DefMI && DefMI != MI)
// We also need to make sure it is safe to move the load.
// Assume there are stores between DefMI and UseMI.
bool SawStore = true;
- if (!DefMI->isSafeToMove(&TII, 0, SawStore))
+ if (!DefMI->isSafeToMove(nullptr, SawStore))
return false;
DEBUG(dbgs() << "Try to fold single def: " << *DefMI
DEBUG(dbgs() << " folded: " << *FoldMI);
LIS.ReplaceMachineInstrInMaps(UseMI, FoldMI);
UseMI->eraseFromParent();
- DefMI->addRegisterDead(LI->reg, 0);
+ DefMI->addRegisterDead(LI->reg, nullptr);
Dead.push_back(DefMI);
++NumDCEFoldedLoads;
return true;
}
+bool LiveRangeEdit::useIsKill(const LiveInterval &LI,
+ const MachineOperand &MO) const {
+ const MachineInstr *MI = MO.getParent();
+ SlotIndex Idx = LIS.getInstructionIndex(MI).getRegSlot();
+ if (LI.Query(Idx).isKill())
+ return true;
+ const TargetRegisterInfo &TRI = *MRI.getTargetRegisterInfo();
+ unsigned SubReg = MO.getSubReg();
+ LaneBitmask LaneMask = TRI.getSubRegIndexLaneMask(SubReg);
+ for (const LiveInterval::SubRange &S : LI.subranges()) {
+ if ((S.LaneMask & LaneMask) != 0 && S.Query(Idx).isKill())
+ return true;
+ }
+ return false;
+}
+
/// Find all live intervals that need to shrink, then remove the instruction.
void LiveRangeEdit::eliminateDeadDef(MachineInstr *MI, ToShrinkSet &ToShrink) {
assert(MI->allDefsAreDead() && "Def isn't really dead");
// Use the same criteria as DeadMachineInstructionElim.
bool SawStore = false;
- if (!MI->isSafeToMove(&TII, 0, SawStore)) {
+ if (!MI->isSafeToMove(nullptr, SawStore)) {
DEBUG(dbgs() << "Can't delete: " << Idx << '\t' << *MI);
return;
}
// Check if MI reads any unreserved physregs.
if (Reg && MOI->readsReg() && !MRI.isReserved(Reg))
ReadsPhysRegs = true;
- else if (MOI->isDef()) {
- for (MCRegUnitIterator Units(Reg, MRI.getTargetRegisterInfo());
- Units.isValid(); ++Units) {
- if (LiveInterval *LI = LIS.getCachedRegUnit(*Units)) {
- if (VNInfo *VNI = LI->getVNInfoAt(Idx))
- LI->removeValNo(VNI);
- }
- }
- }
+ else if (MOI->isDef())
+ LIS.removePhysRegDefAt(Reg, Idx);
continue;
}
LiveInterval &LI = LIS.getInterval(Reg);
// unlikely to change anything. We typically don't want to shrink the
// PIC base register that has lots of uses everywhere.
// Always shrink COPY uses that probably come from live range splitting.
- if (MI->readsVirtualRegister(Reg) &&
- (MI->isCopy() || MOI->isDef() || MRI.hasOneNonDBGUse(Reg) ||
- LI.killedAt(Idx)))
+ if ((MI->readsVirtualRegister(Reg) && (MI->isCopy() || MOI->isDef())) ||
+ (MOI->readsReg() && (MRI.hasOneNonDBGUse(Reg) || useIsKill(LI, *MOI))))
ToShrink.insert(&LI);
// Remove defined value.
if (MOI->isDef()) {
- if (VNInfo *VNI = LI.getVNInfoAt(Idx)) {
- if (TheDelegate)
- TheDelegate->LRE_WillShrinkVirtReg(LI.reg);
- LI.removeValNo(VNI);
- if (LI.empty())
- RegsToErase.push_back(Reg);
- }
+ if (TheDelegate && LI.getVNInfoAt(Idx) != nullptr)
+ TheDelegate->LRE_WillShrinkVirtReg(LI.reg);
+ LIS.removeVRegDefAt(LI, Idx);
+ if (LI.empty())
+ RegsToErase.push_back(Reg);
}
}
ToShrink.pop_back();
if (foldAsLoad(LI, Dead))
continue;
+ unsigned VReg = LI->reg;
if (TheDelegate)
- TheDelegate->LRE_WillShrinkVirtReg(LI->reg);
+ TheDelegate->LRE_WillShrinkVirtReg(VReg);
if (!LIS.shrinkToUses(LI, &Dead))
continue;
// them results in incorrect code.
bool BeingSpilled = false;
for (unsigned i = 0, e = RegsBeingSpilled.size(); i != e; ++i) {
- if (LI->reg == RegsBeingSpilled[i]) {
+ if (VReg == RegsBeingSpilled[i]) {
BeingSpilled = true;
break;
}
// LI may have been separated, create new intervals.
LI->RenumberValues();
- ConnectedVNInfoEqClasses ConEQ(LIS);
- unsigned NumComp = ConEQ.Classify(LI);
- if (NumComp <= 1)
- continue;
- ++NumFracRanges;
- bool IsOriginal = VRM && VRM->getOriginal(LI->reg) == LI->reg;
- DEBUG(dbgs() << NumComp << " components: " << *LI << '\n');
- SmallVector<LiveInterval*, 8> Dups(1, LI);
- for (unsigned i = 1; i != NumComp; ++i) {
- Dups.push_back(&createFrom(LI->reg));
+ SmallVector<LiveInterval*, 8> SplitLIs;
+ LIS.splitSeparateComponents(*LI, SplitLIs);
+ if (!SplitLIs.empty())
+ ++NumFracRanges;
+
+ unsigned Original = VRM ? VRM->getOriginal(VReg) : 0;
+ for (const LiveInterval *SplitLI : SplitLIs) {
// If LI is an original interval that hasn't been split yet, make the new
// intervals their own originals instead of referring to LI. The original
// interval must contain all the split products, and LI doesn't.
- if (IsOriginal)
- VRM->setIsSplitFromReg(Dups.back()->reg, 0);
+ if (Original != VReg && Original != 0)
+ VRM->setIsSplitFromReg(SplitLI->reg, Original);
if (TheDelegate)
- TheDelegate->LRE_DidCloneVirtReg(Dups.back()->reg, LI->reg);
+ TheDelegate->LRE_DidCloneVirtReg(SplitLI->reg, VReg);
}
- ConEQ.Distribute(&Dups[0], MRI);
- DEBUG({
- for (unsigned i = 0; i != NumComp; ++i)
- dbgs() << '\t' << *Dups[i] << '\n';
- });
}
}
+// Keep track of new virtual registers created via
+// MachineRegisterInfo::createVirtualRegister.
+void
+LiveRangeEdit::MRI_NoteNewVirtualRegister(unsigned VReg)
+{
+ if (VRM)
+ VRM->grow();
+
+ NewRegs.push_back(VReg);
+}
+
void
LiveRangeEdit::calculateRegClassAndHint(MachineFunction &MF,
const MachineLoopInfo &Loops,
const MachineBlockFrequencyInfo &MBFI) {
- VirtRegAuxInfo VRAI(MF, LIS, Loops, MBFI);
- for (iterator I = begin(), E = end(); I != E; ++I) {
- LiveInterval &LI = **I;
- if (MRI.recomputeRegClass(LI.reg, MF.getTarget()))
- DEBUG(dbgs() << "Inflated " << PrintReg(LI.reg) << " to "
- << MRI.getRegClass(LI.reg)->getName() << '\n');
- VRAI.CalculateWeightAndHint(LI);
+ VirtRegAuxInfo VRAI(MF, LIS, VRM, Loops, MBFI);
+ for (unsigned I = 0, Size = size(); I < Size; ++I) {
+ LiveInterval &LI = LIS.getInterval(get(I));
+ if (MRI.recomputeRegClass(LI.reg))
+ DEBUG({
+ const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
+ dbgs() << "Inflated " << PrintReg(LI.reg) << " to "
+ << TRI->getRegClassName(MRI.getRegClass(LI.reg)) << '\n';
+ });
+ VRAI.calculateSpillWeightAndHint(LI);
}
}
projects / oota-llvm.git / blobdiff