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-rw-r--r--lib/CodeGen/PreAllocSplitting.cpp91
1 files changed, 30 insertions, 61 deletions
diff --git a/lib/CodeGen/PreAllocSplitting.cpp b/lib/CodeGen/PreAllocSplitting.cpp
index cce5ae8..8f62345 100644
--- a/lib/CodeGen/PreAllocSplitting.cpp
+++ b/lib/CodeGen/PreAllocSplitting.cpp
@@ -39,8 +39,10 @@
using namespace llvm;
static cl::opt<int> PreSplitLimit("pre-split-limit", cl::init(-1), cl::Hidden);
-static cl::opt<int> DeadSplitLimit("dead-split-limit", cl::init(-1), cl::Hidden);
-static cl::opt<int> RestoreFoldLimit("restore-fold-limit", cl::init(-1), cl::Hidden);
+static cl::opt<int> DeadSplitLimit("dead-split-limit", cl::init(-1),
+ cl::Hidden);
+static cl::opt<int> RestoreFoldLimit("restore-fold-limit", cl::init(-1),
+ cl::Hidden);
STATISTIC(NumSplits, "Number of intervals split");
STATISTIC(NumRemats, "Number of intervals split by rematerialization");
@@ -131,17 +133,14 @@ namespace {
private:
- MachineBasicBlock::iterator
- findNextEmptySlot(MachineBasicBlock*, MachineInstr*,
- SlotIndex&);
MachineBasicBlock::iterator
findSpillPoint(MachineBasicBlock*, MachineInstr*, MachineInstr*,
- SmallPtrSet<MachineInstr*, 4>&, SlotIndex&);
+ SmallPtrSet<MachineInstr*, 4>&);
MachineBasicBlock::iterator
findRestorePoint(MachineBasicBlock*, MachineInstr*, SlotIndex,
- SmallPtrSet<MachineInstr*, 4>&, SlotIndex&);
+ SmallPtrSet<MachineInstr*, 4>&);
int CreateSpillStackSlot(unsigned, const TargetRegisterClass *);
@@ -161,7 +160,6 @@ namespace {
bool Rematerialize(unsigned vreg, VNInfo* ValNo,
MachineInstr* DefMI,
MachineBasicBlock::iterator RestorePt,
- SlotIndex RestoreIdx,
SmallPtrSet<MachineInstr*, 4>& RefsInMBB);
MachineInstr* FoldSpill(unsigned vreg, const TargetRegisterClass* RC,
MachineInstr* DefMI,
@@ -208,24 +206,6 @@ X("pre-alloc-splitting", "Pre-Register Allocation Live Interval Splitting");
const PassInfo *const llvm::PreAllocSplittingID = &X;
-
-/// findNextEmptySlot - Find a gap after the given machine instruction in the
-/// instruction index map. If there isn't one, return end().
-MachineBasicBlock::iterator
-PreAllocSplitting::findNextEmptySlot(MachineBasicBlock *MBB, MachineInstr *MI,
- SlotIndex &SpotIndex) {
- MachineBasicBlock::iterator MII = MI;
- if (++MII != MBB->end()) {
- SlotIndex Index =
- LIs->findGapBeforeInstr(LIs->getInstructionIndex(MII));
- if (Index != SlotIndex()) {
- SpotIndex = Index;
- return MII;
- }
- }
- return MBB->end();
-}
-
/// findSpillPoint - Find a gap as far away from the given MI that's suitable
/// for spilling the current live interval. The index must be before any
/// defs and uses of the live interval register in the mbb. Return begin() if
@@ -233,8 +213,7 @@ PreAllocSplitting::findNextEmptySlot(MachineBasicBlock *MBB, MachineInstr *MI,
MachineBasicBlock::iterator
PreAllocSplitting::findSpillPoint(MachineBasicBlock *MBB, MachineInstr *MI,
MachineInstr *DefMI,
- SmallPtrSet<MachineInstr*, 4> &RefsInMBB,
- SlotIndex &SpillIndex) {
+ SmallPtrSet<MachineInstr*, 4> &RefsInMBB) {
MachineBasicBlock::iterator Pt = MBB->begin();
MachineBasicBlock::iterator MII = MI;
@@ -247,8 +226,6 @@ PreAllocSplitting::findSpillPoint(MachineBasicBlock *MBB, MachineInstr *MI,
if (MII == EndPt || RefsInMBB.count(MII)) return Pt;
while (MII != EndPt && !RefsInMBB.count(MII)) {
- SlotIndex Index = LIs->getInstructionIndex(MII);
-
// We can't insert the spill between the barrier (a call), and its
// corresponding call frame setup.
if (MII->getOpcode() == TRI->getCallFrameDestroyOpcode()) {
@@ -259,9 +236,8 @@ PreAllocSplitting::findSpillPoint(MachineBasicBlock *MBB, MachineInstr *MI,
}
}
continue;
- } else if (LIs->hasGapBeforeInstr(Index)) {
+ } else {
Pt = MII;
- SpillIndex = LIs->findGapBeforeInstr(Index, true);
}
if (RefsInMBB.count(MII))
@@ -281,8 +257,7 @@ PreAllocSplitting::findSpillPoint(MachineBasicBlock *MBB, MachineInstr *MI,
MachineBasicBlock::iterator
PreAllocSplitting::findRestorePoint(MachineBasicBlock *MBB, MachineInstr *MI,
SlotIndex LastIdx,
- SmallPtrSet<MachineInstr*, 4> &RefsInMBB,
- SlotIndex &RestoreIndex) {
+ SmallPtrSet<MachineInstr*, 4> &RefsInMBB) {
// FIXME: Allow spill to be inserted to the beginning of the mbb. Update mbb
// begin index accordingly.
MachineBasicBlock::iterator Pt = MBB->end();
@@ -306,7 +281,6 @@ PreAllocSplitting::findRestorePoint(MachineBasicBlock *MBB, MachineInstr *MI,
SlotIndex Index = LIs->getInstructionIndex(MII);
if (Index > LastIdx)
break;
- SlotIndex Gap = LIs->findGapBeforeInstr(Index);
// We can't insert a restore between the barrier (a call) and its
// corresponding call frame teardown.
@@ -315,9 +289,8 @@ PreAllocSplitting::findRestorePoint(MachineBasicBlock *MBB, MachineInstr *MI,
if (MII == EndPt || RefsInMBB.count(MII)) return Pt;
++MII;
} while (MII->getOpcode() != TRI->getCallFrameDestroyOpcode());
- } else if (Gap != SlotIndex()) {
+ } else {
Pt = MII;
- RestoreIndex = Gap;
}
if (RefsInMBB.count(MII))
@@ -339,7 +312,7 @@ int PreAllocSplitting::CreateSpillStackSlot(unsigned Reg,
if (I != IntervalSSMap.end()) {
SS = I->second;
} else {
- SS = MFI->CreateStackObject(RC->getSize(), RC->getAlignment());
+ SS = MFI->CreateSpillStackObject(RC->getSize(), RC->getAlignment());
IntervalSSMap[Reg] = SS;
}
@@ -364,10 +337,10 @@ PreAllocSplitting::IsAvailableInStack(MachineBasicBlock *DefMBB,
if (!DefMBB)
return false;
- DenseMap<unsigned, int>::iterator I = IntervalSSMap.find(Reg);
+ DenseMap<unsigned, int>::const_iterator I = IntervalSSMap.find(Reg);
if (I == IntervalSSMap.end())
return false;
- DenseMap<SlotIndex, SlotIndex>::iterator
+ DenseMap<SlotIndex, SlotIndex>::const_iterator
II = Def2SpillMap.find(DefIndex);
if (II == Def2SpillMap.end())
return false;
@@ -740,7 +713,7 @@ void PreAllocSplitting::ReconstructLiveInterval(LiveInterval* LI) {
DefIdx = DefIdx.getDefIndex();
assert(DI->getOpcode() != TargetInstrInfo::PHI &&
- "Following NewVN isPHIDef flag incorrect. Fix me!");
+ "PHI instr in code during pre-alloc splitting.");
VNInfo* NewVN = LI->getNextValue(DefIdx, 0, true, Alloc);
// If the def is a move, set the copy field.
@@ -896,25 +869,22 @@ void PreAllocSplitting::RenumberValno(VNInfo* VN) {
bool PreAllocSplitting::Rematerialize(unsigned VReg, VNInfo* ValNo,
MachineInstr* DefMI,
MachineBasicBlock::iterator RestorePt,
- SlotIndex RestoreIdx,
SmallPtrSet<MachineInstr*, 4>& RefsInMBB) {
MachineBasicBlock& MBB = *RestorePt->getParent();
MachineBasicBlock::iterator KillPt = BarrierMBB->end();
- SlotIndex KillIdx;
if (!ValNo->isDefAccurate() || DefMI->getParent() == BarrierMBB)
- KillPt = findSpillPoint(BarrierMBB, Barrier, NULL, RefsInMBB, KillIdx);
+ KillPt = findSpillPoint(BarrierMBB, Barrier, NULL, RefsInMBB);
else
- KillPt = findNextEmptySlot(DefMI->getParent(), DefMI, KillIdx);
+ KillPt = next(MachineBasicBlock::iterator(DefMI));
if (KillPt == DefMI->getParent()->end())
return false;
- TII->reMaterialize(MBB, RestorePt, VReg, 0, DefMI);
- LIs->InsertMachineInstrInMaps(prior(RestorePt), RestoreIdx);
+ TII->reMaterialize(MBB, RestorePt, VReg, 0, DefMI, TRI);
+ SlotIndex RematIdx = LIs->InsertMachineInstrInMaps(prior(RestorePt));
ReconstructLiveInterval(CurrLI);
- SlotIndex RematIdx = LIs->getInstructionIndex(prior(RestorePt));
RematIdx = RematIdx.getDefIndex();
RenumberValno(CurrLI->findDefinedVNInfoForRegInt(RematIdx));
@@ -955,7 +925,7 @@ MachineInstr* PreAllocSplitting::FoldSpill(unsigned vreg,
if (I != IntervalSSMap.end()) {
SS = I->second;
} else {
- SS = MFI->CreateStackObject(RC->getSize(), RC->getAlignment());
+ SS = MFI->CreateSpillStackObject(RC->getSize(), RC->getAlignment());
}
MachineInstr* FMI = TII->foldMemoryOperand(*MBB->getParent(),
@@ -1086,17 +1056,15 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
}
// Find a point to restore the value after the barrier.
- SlotIndex RestoreIndex;
MachineBasicBlock::iterator RestorePt =
- findRestorePoint(BarrierMBB, Barrier, LR->end, RefsInMBB, RestoreIndex);
+ findRestorePoint(BarrierMBB, Barrier, LR->end, RefsInMBB);
if (RestorePt == BarrierMBB->end()) {
DEBUG(errs() << "FAILED (could not find a suitable restore point).\n");
return false;
}
if (DefMI && LIs->isReMaterializable(*LI, ValNo, DefMI))
- if (Rematerialize(LI->reg, ValNo, DefMI, RestorePt,
- RestoreIndex, RefsInMBB)) {
+ if (Rematerialize(LI->reg, ValNo, DefMI, RestorePt, RefsInMBB)) {
DEBUG(errs() << "success (remat).\n");
return true;
}
@@ -1114,7 +1082,7 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
SpillIndex = LIs->getInstructionIndex(SpillMI);
} else {
MachineBasicBlock::iterator SpillPt =
- findSpillPoint(BarrierMBB, Barrier, NULL, RefsInMBB, SpillIndex);
+ findSpillPoint(BarrierMBB, Barrier, NULL, RefsInMBB);
if (SpillPt == BarrierMBB->begin()) {
DEBUG(errs() << "FAILED (could not find a suitable spill point).\n");
return false; // No gap to insert spill.
@@ -1124,10 +1092,10 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
SS = CreateSpillStackSlot(CurrLI->reg, RC);
TII->storeRegToStackSlot(*BarrierMBB, SpillPt, CurrLI->reg, true, SS, RC);
SpillMI = prior(SpillPt);
- LIs->InsertMachineInstrInMaps(SpillMI, SpillIndex);
+ SpillIndex = LIs->InsertMachineInstrInMaps(SpillMI);
}
} else if (!IsAvailableInStack(DefMBB, CurrLI->reg, ValNo->def,
- RestoreIndex, SpillIndex, SS)) {
+ LIs->getZeroIndex(), SpillIndex, SS)) {
// If it's already split, just restore the value. There is no need to spill
// the def again.
if (!DefMI) {
@@ -1144,13 +1112,13 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
if (DefMBB == BarrierMBB) {
// Add spill after the def and the last use before the barrier.
SpillPt = findSpillPoint(BarrierMBB, Barrier, DefMI,
- RefsInMBB, SpillIndex);
+ RefsInMBB);
if (SpillPt == DefMBB->begin()) {
DEBUG(errs() << "FAILED (could not find a suitable spill point).\n");
return false; // No gap to insert spill.
}
} else {
- SpillPt = findNextEmptySlot(DefMBB, DefMI, SpillIndex);
+ SpillPt = next(MachineBasicBlock::iterator(DefMI));
if (SpillPt == DefMBB->end()) {
DEBUG(errs() << "FAILED (could not find a suitable spill point).\n");
return false; // No gap to insert spill.
@@ -1160,7 +1128,7 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
SS = CreateSpillStackSlot(CurrLI->reg, RC);
TII->storeRegToStackSlot(*DefMBB, SpillPt, CurrLI->reg, false, SS, RC);
SpillMI = prior(SpillPt);
- LIs->InsertMachineInstrInMaps(SpillMI, SpillIndex);
+ SpillIndex = LIs->InsertMachineInstrInMaps(SpillMI);
}
}
@@ -1170,6 +1138,7 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
// Add restore.
bool FoldedRestore = false;
+ SlotIndex RestoreIndex;
if (MachineInstr* LMI = FoldRestore(CurrLI->reg, RC, Barrier,
BarrierMBB, SS, RefsInMBB)) {
RestorePt = LMI;
@@ -1178,7 +1147,7 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
} else {
TII->loadRegFromStackSlot(*BarrierMBB, RestorePt, CurrLI->reg, SS, RC);
MachineInstr *LoadMI = prior(RestorePt);
- LIs->InsertMachineInstrInMaps(LoadMI, RestoreIndex);
+ RestoreIndex = LIs->InsertMachineInstrInMaps(LoadMI);
}
// Update spill stack slot live interval.
@@ -1398,7 +1367,7 @@ bool PreAllocSplitting::removeDeadSpills(SmallPtrSet<LiveInterval*, 8>& split) {
// Otherwise, this is a load-store case, so DCE them.
for (SmallPtrSet<MachineInstr*, 4>::iterator UI =
VNUseCount[CurrVN].begin(), UE = VNUseCount[CurrVN].end();
- UI != UI; ++UI) {
+ UI != UE; ++UI) {
LIs->RemoveMachineInstrFromMaps(*UI);
(*UI)->eraseFromParent();
}
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