#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/ADT/BitVector.h"
+#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include <vector>
MachineFunctionPass(&ID), ColorWithRegs(RegColor), NextColor(-1) {}
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.setPreservesCFG();
AU.addRequired<LiveStacks>();
AU.addRequired<VirtRegMap>();
AU.addPreserved<VirtRegMap>();
unsigned OldReg, unsigned NewReg);
void UnfoldAndRewriteInstruction(MachineInstr *MI, int OldFI,
unsigned Reg, const TargetRegisterClass *RC,
+ SmallSet<unsigned, 4> &Defs,
MachineFunction &MF);
bool AllMemRefsCanBeUnfolded(int SS);
bool RemoveDeadStores(MachineBasicBlock* MBB);
return false;
// Rewrite all MO_FrameIndex operands.
+ SmallVector<SmallSet<unsigned, 4>, 4> NewDefs(MF.getNumBlockIDs());
for (unsigned SS = 0, SE = SSRefs.size(); SS != SE; ++SS) {
bool isReg = SlotIsReg[SS];
int NewFI = SlotMapping[SS];
if (NewFI == -1 || (NewFI == (int)SS && !isReg))
continue;
+ const TargetRegisterClass *RC = LS->getIntervalRegClass(SS);
SmallVector<MachineInstr*, 8> &RefMIs = SSRefs[SS];
for (unsigned i = 0, e = RefMIs.size(); i != e; ++i)
if (!isReg)
RewriteInstruction(RefMIs[i], SS, NewFI, MF);
else {
// Rewrite to use a register instead.
- const TargetRegisterClass *RC = LS->getIntervalRegClass(SS);
- UnfoldAndRewriteInstruction(RefMIs[i], SS, NewFI, RC, MF);
+ unsigned MBBId = RefMIs[i]->getParent()->getNumber();
+ SmallSet<unsigned, 4> &Defs = NewDefs[MBBId];
+ UnfoldAndRewriteInstruction(RefMIs[i], SS, NewFI, RC, Defs, MF);
}
}
if (MII == MBB->begin())
return false;
+ SmallVector<MachineOperand*, 4> Uses;
SmallVector<MachineOperand*, 4> Refs;
while (--MII != MBB->begin()) {
bool FoundDef = false; // Not counting 2address def.
- bool FoundUse = false;
- bool FoundKill = false;
+
+ Uses.clear();
const TargetInstrDesc &TID = MII->getDesc();
for (unsigned i = 0, e = MII->getNumOperands(); i != e; ++i) {
MachineOperand &MO = MII->getOperand(i);
if (Reg == 0)
continue;
if (Reg == OldReg) {
- const TargetRegisterClass *RC = getInstrOperandRegClass(TRI, TID, i);
+ if (MO.isImplicit())
+ return false;
+
+ // Abort the use is actually a sub-register def. We don't have enough
+ // information to figure out if it is really legal.
+ if (MO.getSubReg() ||
+ TID.getOpcode() == TargetInstrInfo::EXTRACT_SUBREG ||
+ TID.getOpcode() == TargetInstrInfo::INSERT_SUBREG ||
+ TID.getOpcode() == TargetInstrInfo::SUBREG_TO_REG)
+ return false;
+
+ const TargetRegisterClass *RC = TID.OpInfo[i].getRegClass(TRI);
if (RC && !RC->contains(NewReg))
return false;
if (MO.isUse()) {
- FoundUse = true;
- if (MO.isKill())
- FoundKill = true;
- Refs.push_back(&MO);
+ Uses.push_back(&MO);
} else {
Refs.push_back(&MO);
if (!MII->isRegTiedToUseOperand(i))
return false;
}
}
+
if (FoundDef) {
+ // Found non-two-address def. Stop here.
for (unsigned i = 0, e = Refs.size(); i != e; ++i)
Refs[i]->setReg(NewReg);
return true;
}
+
+ // Two-address uses must be updated as well.
+ for (unsigned i = 0, e = Uses.size(); i != e; ++i)
+ Refs.push_back(Uses[i]);
}
return false;
}
if (Reg == 0)
continue;
if (Reg == OldReg) {
- if (MO.isDef())
+ if (MO.isDef() || MO.isImplicit())
+ return false;
+
+ // Abort the use is actually a sub-register use. We don't have enough
+ // information to figure out if it is really legal.
+ if (MO.getSubReg() ||
+ TID.getOpcode() == TargetInstrInfo::EXTRACT_SUBREG)
return false;
- const TargetRegisterClass *RC = getInstrOperandRegClass(TRI, TID, i);
+ const TargetRegisterClass *RC = TID.OpInfo[i].getRegClass(TRI);
if (RC && !RC->contains(NewReg))
return false;
FoundUse = true;
if (MO.isKill())
FoundKill = true;
+
Uses.push_back(&MO);
} else if (TRI->regsOverlap(Reg, NewReg) ||
TRI->regsOverlap(Reg, OldReg))
/// UnfoldAndRewriteInstruction - Rewrite specified instruction by unfolding
/// folded memory references and replacing those references with register
/// references instead.
-void StackSlotColoring::UnfoldAndRewriteInstruction(MachineInstr *MI, int OldFI,
- unsigned Reg,
- const TargetRegisterClass *RC,
- MachineFunction &MF) {
+void
+StackSlotColoring::UnfoldAndRewriteInstruction(MachineInstr *MI, int OldFI,
+ unsigned Reg,
+ const TargetRegisterClass *RC,
+ SmallSet<unsigned, 4> &Defs,
+ MachineFunction &MF) {
MachineBasicBlock *MBB = MI->getParent();
if (unsigned DstReg = TII->isLoadFromStackSlot(MI, OldFI)) {
if (PropagateForward(MI, MBB, DstReg, Reg)) {
TII->copyRegToReg(*MBB, MI, DstReg, Reg, RC, RC);
++NumRegRepl;
}
+
+ if (!Defs.count(Reg)) {
+ // If this is the first use of Reg in this MBB and it wasn't previously
+ // defined in MBB, add it to livein.
+ MBB->addLiveIn(Reg);
+ Defs.insert(Reg);
+ }
} else if (unsigned SrcReg = TII->isStoreToStackSlot(MI, OldFI)) {
if (MI->killsRegister(SrcReg) && PropagateBackward(MI, MBB, SrcReg, Reg)) {
DOUT << "Eliminated store: ";
TII->copyRegToReg(*MBB, MI, Reg, SrcReg, RC, RC);
++NumRegRepl;
}
+
+ // Remember reg has been defined in MBB.
+ Defs.insert(Reg);
} else {
SmallVector<MachineInstr*, 4> NewMIs;
bool Success = TII->unfoldMemoryOperand(MF, MI, Reg, false, false, NewMIs);
+ Success = Success; // Silence compiler warning.
assert(Success && "Failed to unfold!");
- MBB->insert(MI, NewMIs[0]);
+ MachineInstr *NewMI = NewMIs[0];
+ MBB->insert(MI, NewMI);
++NumRegRepl;
+
+ if (NewMI->readsRegister(Reg)) {
+ if (!Defs.count(Reg))
+ // If this is the first use of Reg in this MBB and it wasn't previously
+ // defined in MBB, add it to livein.
+ MBB->addLiveIn(Reg);
+ Defs.insert(Reg);
+ }
}
MBB->erase(MI);
}