#define DEBUG_TYPE "regalloc"
#include "AllocationOrder.h"
#include "InterferenceCache.h"
+#include "LiveDebugVariables.h"
#include "LiveRangeEdit.h"
#include "RegAllocBase.h"
#include "Spiller.h"
RS_New, ///< Never seen before.
RS_First, ///< First time in the queue.
RS_Second, ///< Second time in the queue.
- RS_Region, ///< Produced by region splitting.
- RS_Block, ///< Produced by per-block splitting.
+ RS_Global, ///< Produced by global splitting.
RS_Local, ///< Produced by local splitting.
RS_Spill ///< Produced by spilling.
};
/// Cached per-block interference maps
InterferenceCache IntfCache;
- /// All basic blocks where the current register is live.
+ /// All basic blocks where the current register has uses.
SmallVector<SpillPlacement::BlockConstraint, 8> SplitConstraints;
/// Global live range splitting candidate info.
struct GlobalSplitCandidate {
unsigned PhysReg;
BitVector LiveBundles;
+ SmallVector<unsigned, 8> ActiveBlocks;
+
+ void reset(unsigned Reg) {
+ PhysReg = Reg;
+ LiveBundles.clear();
+ ActiveBlocks.clear();
+ }
};
/// Candidate info for for each PhysReg in AllocationOrder.
void LRE_WillShrinkVirtReg(unsigned);
void LRE_DidCloneVirtReg(unsigned, unsigned);
- float calcSplitConstraints(unsigned);
- float calcGlobalSplitCost(const BitVector&);
- void splitAroundRegion(LiveInterval&, unsigned, const BitVector&,
+ bool addSplitConstraints(InterferenceCache::Cursor, float&);
+ void addThroughConstraints(InterferenceCache::Cursor, ArrayRef<unsigned>);
+ void growRegion(GlobalSplitCandidate &Cand, InterferenceCache::Cursor);
+ float calcGlobalSplitCost(GlobalSplitCandidate&, InterferenceCache::Cursor);
+ void splitAroundRegion(LiveInterval&, GlobalSplitCandidate&,
SmallVectorImpl<LiveInterval*>&);
void calcGapWeights(unsigned, SmallVectorImpl<float>&);
SlotIndex getPrevMappedIndex(const MachineInstr*);
}
RAGreedy::RAGreedy(): MachineFunctionPass(ID), LRStage(RS_New) {
+ initializeLiveDebugVariablesPass(*PassRegistry::getPassRegistry());
initializeSlotIndexesPass(*PassRegistry::getPassRegistry());
initializeLiveIntervalsPass(*PassRegistry::getPassRegistry());
initializeSlotIndexesPass(*PassRegistry::getPassRegistry());
AU.addRequired<LiveIntervals>();
AU.addRequired<SlotIndexes>();
AU.addPreserved<SlotIndexes>();
+ AU.addRequired<LiveDebugVariables>();
+ AU.addPreserved<LiveDebugVariables>();
if (StrongPHIElim)
AU.addRequiredID(StrongPHIEliminationID);
AU.addRequiredTransitive<RegisterCoalescer>();
void RAGreedy::releaseMemory() {
SpillerInstance.reset(0);
LRStage.clear();
+ GlobalCand.clear();
RegAllocBase::releaseMemory();
}
//===----------------------------------------------------------------------===//
/// canEvict - Return true if all interferences between VirtReg and PhysReg can
-/// be evicted. Set maxWeight to the maximal spill weight of an interference.
+/// be evicted.
+/// Return false if any interference is heavier than MaxWeight.
+/// On return, set MaxWeight to the maximal spill weight of an interference.
bool RAGreedy::canEvictInterference(LiveInterval &VirtReg, unsigned PhysReg,
float &MaxWeight) {
float Weight = 0;
for (const unsigned *AliasI = TRI->getOverlaps(PhysReg); *AliasI; ++AliasI) {
LiveIntervalUnion::Query &Q = query(VirtReg, *AliasI);
- // If there is 10 or more interferences, chances are one is smaller.
- if (Q.collectInterferingVRegs(10) >= 10)
+ // If there is 10 or more interferences, chances are one is heavier.
+ if (Q.collectInterferingVRegs(10, MaxWeight) >= 10)
return false;
- // Check if any interfering live range is heavier than VirtReg.
- for (unsigned i = 0, e = Q.interferingVRegs().size(); i != e; ++i) {
- LiveInterval *Intf = Q.interferingVRegs()[i];
+ // Check if any interfering live range is heavier than MaxWeight.
+ for (unsigned i = Q.interferingVRegs().size(); i; --i) {
+ LiveInterval *Intf = Q.interferingVRegs()[i - 1];
if (TargetRegisterInfo::isPhysicalRegister(Intf->reg))
return false;
- if (Intf->weight >= VirtReg.weight)
+ if (Intf->weight >= MaxWeight)
return false;
Weight = std::max(Weight, Intf->weight);
}
NamedRegionTimer T("Evict", TimerGroupName, TimePassesIsEnabled);
// Keep track of the lightest single interference seen so far.
- float BestWeight = 0;
+ float BestWeight = VirtReg.weight;
unsigned BestPhys = 0;
Order.rewind();
while (unsigned PhysReg = Order.next()) {
- float Weight = 0;
+ float Weight = BestWeight;
if (!canEvictInterference(VirtReg, PhysReg, Weight))
continue;
// This is an eviction candidate.
- DEBUG(dbgs() << "max " << PrintReg(PhysReg, TRI) << " interference = "
+ DEBUG(dbgs() << PrintReg(PhysReg, TRI) << " interference = "
<< Weight << '\n');
if (BestPhys && Weight >= BestWeight)
continue;
// Region Splitting
//===----------------------------------------------------------------------===//
-/// calcSplitConstraints - Fill out the SplitConstraints vector based on the
-/// interference pattern in Physreg and its aliases. Return the static cost of
-/// this split, assuming that all preferences in SplitConstraints are met.
-float RAGreedy::calcSplitConstraints(unsigned PhysReg) {
- InterferenceCache::Cursor Intf(IntfCache, PhysReg);
+/// addSplitConstraints - Fill out the SplitConstraints vector based on the
+/// interference pattern in Physreg and its aliases. Add the constraints to
+/// SpillPlacement and return the static cost of this split in Cost, assuming
+/// that all preferences in SplitConstraints are met.
+/// Return false if there are no bundles with positive bias.
+bool RAGreedy::addSplitConstraints(InterferenceCache::Cursor Intf,
+ float &Cost) {
+ ArrayRef<SplitAnalysis::BlockInfo> UseBlocks = SA->getUseBlocks();
// Reset interference dependent info.
- SplitConstraints.resize(SA->LiveBlocks.size());
+ SplitConstraints.resize(UseBlocks.size());
float StaticCost = 0;
- for (unsigned i = 0, e = SA->LiveBlocks.size(); i != e; ++i) {
- SplitAnalysis::BlockInfo &BI = SA->LiveBlocks[i];
+ for (unsigned i = 0; i != UseBlocks.size(); ++i) {
+ const SplitAnalysis::BlockInfo &BI = UseBlocks[i];
SpillPlacement::BlockConstraint &BC = SplitConstraints[i];
BC.Number = BI.MBB->getNumber();
Intf.moveToBlock(BC.Number);
- BC.Entry = (BI.Uses && BI.LiveIn) ?
- SpillPlacement::PrefReg : SpillPlacement::DontCare;
- BC.Exit = (BI.Uses && BI.LiveOut) ?
- SpillPlacement::PrefReg : SpillPlacement::DontCare;
+ BC.Entry = BI.LiveIn ? SpillPlacement::PrefReg : SpillPlacement::DontCare;
+ BC.Exit = BI.LiveOut ? SpillPlacement::PrefReg : SpillPlacement::DontCare;
if (!Intf.hasInterference())
continue;
// Interference for the live-in value.
if (BI.LiveIn) {
if (Intf.first() <= Indexes->getMBBStartIdx(BC.Number))
- BC.Entry = SpillPlacement::MustSpill, Ins += BI.Uses;
- else if (!BI.Uses)
- BC.Entry = SpillPlacement::PrefSpill;
+ BC.Entry = SpillPlacement::MustSpill, ++Ins;
else if (Intf.first() < BI.FirstUse)
BC.Entry = SpillPlacement::PrefSpill, ++Ins;
else if (Intf.first() < (BI.LiveThrough ? BI.LastUse : BI.Kill))
// Interference for the live-out value.
if (BI.LiveOut) {
- if (Intf.last() >= BI.LastSplitPoint)
- BC.Exit = SpillPlacement::MustSpill, Ins += BI.Uses;
- else if (!BI.Uses)
- BC.Exit = SpillPlacement::PrefSpill;
+ if (Intf.last() >= SA->getLastSplitPoint(BC.Number))
+ BC.Exit = SpillPlacement::MustSpill, ++Ins;
else if (Intf.last() > BI.LastUse)
BC.Exit = SpillPlacement::PrefSpill, ++Ins;
else if (Intf.last() > (BI.LiveThrough ? BI.FirstUse : BI.Def))
if (Ins)
StaticCost += Ins * SpillPlacer->getBlockFrequency(BC.Number);
}
- return StaticCost;
+ Cost = StaticCost;
+
+ // Add constraints for use-blocks. Note that these are the only constraints
+ // that may add a positive bias, it is downhill from here.
+ SpillPlacer->addConstraints(SplitConstraints);
+ return SpillPlacer->scanActiveBundles();
}
+/// addThroughConstraints - Add constraints and links to SpillPlacer from the
+/// live-through blocks in Blocks.
+void RAGreedy::addThroughConstraints(InterferenceCache::Cursor Intf,
+ ArrayRef<unsigned> Blocks) {
+ const unsigned GroupSize = 8;
+ SpillPlacement::BlockConstraint BCS[GroupSize];
+ unsigned TBS[GroupSize];
+ unsigned B = 0, T = 0;
+
+ for (unsigned i = 0; i != Blocks.size(); ++i) {
+ unsigned Number = Blocks[i];
+ Intf.moveToBlock(Number);
+
+ if (!Intf.hasInterference()) {
+ assert(T < GroupSize && "Array overflow");
+ TBS[T] = Number;
+ if (++T == GroupSize) {
+ SpillPlacer->addLinks(ArrayRef<unsigned>(TBS, T));
+ T = 0;
+ }
+ continue;
+ }
+
+ assert(B < GroupSize && "Array overflow");
+ BCS[B].Number = Number;
+
+ // Interference for the live-in value.
+ if (Intf.first() <= Indexes->getMBBStartIdx(Number))
+ BCS[B].Entry = SpillPlacement::MustSpill;
+ else
+ BCS[B].Entry = SpillPlacement::PrefSpill;
+
+ // Interference for the live-out value.
+ if (Intf.last() >= SA->getLastSplitPoint(Number))
+ BCS[B].Exit = SpillPlacement::MustSpill;
+ else
+ BCS[B].Exit = SpillPlacement::PrefSpill;
+
+ if (++B == GroupSize) {
+ ArrayRef<SpillPlacement::BlockConstraint> Array(BCS, B);
+ SpillPlacer->addConstraints(Array);
+ B = 0;
+ }
+ }
+
+ ArrayRef<SpillPlacement::BlockConstraint> Array(BCS, B);
+ SpillPlacer->addConstraints(Array);
+ SpillPlacer->addLinks(ArrayRef<unsigned>(TBS, T));
+}
+
+void RAGreedy::growRegion(GlobalSplitCandidate &Cand,
+ InterferenceCache::Cursor Intf) {
+ // Keep track of through blocks that have not been added to SpillPlacer.
+ BitVector Todo = SA->getThroughBlocks();
+ SmallVectorImpl<unsigned> &ActiveBlocks = Cand.ActiveBlocks;
+ unsigned AddedTo = 0;
+#ifndef NDEBUG
+ unsigned Visited = 0;
+#endif
+
+ for (;;) {
+ ArrayRef<unsigned> NewBundles = SpillPlacer->getRecentPositive();
+ if (NewBundles.empty())
+ break;
+ // Find new through blocks in the periphery of PrefRegBundles.
+ for (int i = 0, e = NewBundles.size(); i != e; ++i) {
+ unsigned Bundle = NewBundles[i];
+ // Look at all blocks connected to Bundle in the full graph.
+ ArrayRef<unsigned> Blocks = Bundles->getBlocks(Bundle);
+ for (ArrayRef<unsigned>::iterator I = Blocks.begin(), E = Blocks.end();
+ I != E; ++I) {
+ unsigned Block = *I;
+ if (!Todo.test(Block))
+ continue;
+ Todo.reset(Block);
+ // This is a new through block. Add it to SpillPlacer later.
+ ActiveBlocks.push_back(Block);
+#ifndef NDEBUG
+ ++Visited;
+#endif
+ }
+ }
+ // Any new blocks to add?
+ if (ActiveBlocks.size() > AddedTo) {
+ ArrayRef<unsigned> Add(&ActiveBlocks[AddedTo],
+ ActiveBlocks.size() - AddedTo);
+ addThroughConstraints(Intf, Add);
+ AddedTo = ActiveBlocks.size();
+ }
+ // Perhaps iterating can enable more bundles?
+ SpillPlacer->iterate();
+ }
+ DEBUG(dbgs() << ", v=" << Visited);
+}
+
/// calcGlobalSplitCost - Return the global split cost of following the split
/// pattern in LiveBundles. This cost should be added to the local cost of the
/// interference pattern in SplitConstraints.
///
-float RAGreedy::calcGlobalSplitCost(const BitVector &LiveBundles) {
+float RAGreedy::calcGlobalSplitCost(GlobalSplitCandidate &Cand,
+ InterferenceCache::Cursor Intf) {
float GlobalCost = 0;
- for (unsigned i = 0, e = SA->LiveBlocks.size(); i != e; ++i) {
- SplitAnalysis::BlockInfo &BI = SA->LiveBlocks[i];
+ const BitVector &LiveBundles = Cand.LiveBundles;
+ ArrayRef<SplitAnalysis::BlockInfo> UseBlocks = SA->getUseBlocks();
+ for (unsigned i = 0; i != UseBlocks.size(); ++i) {
+ const SplitAnalysis::BlockInfo &BI = UseBlocks[i];
SpillPlacement::BlockConstraint &BC = SplitConstraints[i];
bool RegIn = LiveBundles[Bundles->getBundle(BC.Number, 0)];
bool RegOut = LiveBundles[Bundles->getBundle(BC.Number, 1)];
unsigned Ins = 0;
- if (!BI.Uses)
- Ins += RegIn != RegOut;
- else {
- if (BI.LiveIn)
- Ins += RegIn != (BC.Entry == SpillPlacement::PrefReg);
- if (BI.LiveOut)
- Ins += RegOut != (BC.Exit == SpillPlacement::PrefReg);
- }
+ if (BI.LiveIn)
+ Ins += RegIn != (BC.Entry == SpillPlacement::PrefReg);
+ if (BI.LiveOut)
+ Ins += RegOut != (BC.Exit == SpillPlacement::PrefReg);
if (Ins)
GlobalCost += Ins * SpillPlacer->getBlockFrequency(BC.Number);
}
+
+ for (unsigned i = 0, e = Cand.ActiveBlocks.size(); i != e; ++i) {
+ unsigned Number = Cand.ActiveBlocks[i];
+ bool RegIn = LiveBundles[Bundles->getBundle(Number, 0)];
+ bool RegOut = LiveBundles[Bundles->getBundle(Number, 1)];
+ if (!RegIn && !RegOut)
+ continue;
+ if (RegIn && RegOut) {
+ // We need double spill code if this block has interference.
+ Intf.moveToBlock(Number);
+ if (Intf.hasInterference())
+ GlobalCost += 2*SpillPlacer->getBlockFrequency(Number);
+ continue;
+ }
+ // live-in / stack-out or stack-in live-out.
+ GlobalCost += SpillPlacer->getBlockFrequency(Number);
+ }
return GlobalCost;
}
/// avoiding interference. The 'stack' interval is the complement constructed by
/// SplitEditor. It will contain the rest.
///
-void RAGreedy::splitAroundRegion(LiveInterval &VirtReg, unsigned PhysReg,
- const BitVector &LiveBundles,
+void RAGreedy::splitAroundRegion(LiveInterval &VirtReg,
+ GlobalSplitCandidate &Cand,
SmallVectorImpl<LiveInterval*> &NewVRegs) {
+ const BitVector &LiveBundles = Cand.LiveBundles;
+
DEBUG({
- dbgs() << "Splitting around region for " << PrintReg(PhysReg, TRI)
+ dbgs() << "Splitting around region for " << PrintReg(Cand.PhysReg, TRI)
<< " with bundles";
for (int i = LiveBundles.find_first(); i>=0; i = LiveBundles.find_next(i))
dbgs() << " EB#" << i;
dbgs() << ".\n";
});
- InterferenceCache::Cursor Intf(IntfCache, PhysReg);
+ InterferenceCache::Cursor Intf(IntfCache, Cand.PhysReg);
LiveRangeEdit LREdit(VirtReg, NewVRegs, this);
SE->reset(LREdit);
// Create the main cross-block interval.
- SE->openIntv();
+ const unsigned MainIntv = SE->openIntv();
// First add all defs that are live out of a block.
- for (unsigned i = 0, e = SA->LiveBlocks.size(); i != e; ++i) {
- SplitAnalysis::BlockInfo &BI = SA->LiveBlocks[i];
+ ArrayRef<SplitAnalysis::BlockInfo> UseBlocks = SA->getUseBlocks();
+ for (unsigned i = 0; i != UseBlocks.size(); ++i) {
+ const SplitAnalysis::BlockInfo &BI = UseBlocks[i];
bool RegIn = LiveBundles[Bundles->getBundle(BI.MBB->getNumber(), 0)];
bool RegOut = LiveBundles[Bundles->getBundle(BI.MBB->getNumber(), 1)];
+ // Create separate intervals for isolated blocks with multiple uses.
+ if (!RegIn && !RegOut && BI.FirstUse != BI.LastUse) {
+ DEBUG(dbgs() << "BB#" << BI.MBB->getNumber() << " isolated.\n");
+ SE->splitSingleBlock(BI);
+ SE->selectIntv(MainIntv);
+ continue;
+ }
+
// Should the register be live out?
if (!BI.LiveOut || !RegOut)
continue;
Intf.moveToBlock(BI.MBB->getNumber());
DEBUG(dbgs() << "BB#" << BI.MBB->getNumber() << " -> EB#"
<< Bundles->getBundle(BI.MBB->getNumber(), 1)
- << " [" << Start << ';' << BI.LastSplitPoint << '-'
- << Stop << ") intf [" << Intf.first() << ';' << Intf.last()
- << ')');
+ << " [" << Start << ';'
+ << SA->getLastSplitPoint(BI.MBB->getNumber()) << '-' << Stop
+ << ") intf [" << Intf.first() << ';' << Intf.last() << ')');
// The interference interval should either be invalid or overlap MBB.
assert((!Intf.hasInterference() || Intf.first() < Stop)
if (!Intf.hasInterference()) {
// Block is interference-free.
DEBUG(dbgs() << ", no interference");
- if (!BI.Uses) {
- assert(BI.LiveThrough && "No uses, but not live through block?");
- // Block is live-through without interference.
- DEBUG(dbgs() << ", no uses"
- << (RegIn ? ", live-through.\n" : ", stack in.\n"));
- if (!RegIn)
- SE->enterIntvAtEnd(*BI.MBB);
- continue;
- }
if (!BI.LiveThrough) {
DEBUG(dbgs() << ", not live-through.\n");
SE->useIntv(SE->enterIntvBefore(BI.Def), Stop);
continue;
}
-
- if (!BI.Uses) {
- // No uses in block, avoid interference by reloading as late as possible.
- DEBUG(dbgs() << ", no uses.\n");
- SlotIndex SegStart = SE->enterIntvAtEnd(*BI.MBB);
- assert(SegStart >= Intf.last() && "Couldn't avoid interference");
- continue;
- }
-
+ SlotIndex LastSplitPoint = SA->getLastSplitPoint(BI.MBB->getNumber());
if (Intf.last().getBoundaryIndex() < BI.LastUse) {
// There are interference-free uses at the end of the block.
// Find the first use that can get the live-out register.
SlotIndex Use = *UI;
assert(Use <= BI.LastUse && "Couldn't find last use");
// Only attempt a split befroe the last split point.
- if (Use.getBaseIndex() <= BI.LastSplitPoint) {
+ if (Use.getBaseIndex() <= LastSplitPoint) {
DEBUG(dbgs() << ", free use at " << Use << ".\n");
SlotIndex SegStart = SE->enterIntvBefore(Use);
assert(SegStart >= Intf.last() && "Couldn't avoid interference");
- assert(SegStart < BI.LastSplitPoint && "Impossible split point");
+ assert(SegStart < LastSplitPoint && "Impossible split point");
SE->useIntv(SegStart, Stop);
continue;
}
}
// Now all defs leading to live bundles are handled, do everything else.
- for (unsigned i = 0, e = SA->LiveBlocks.size(); i != e; ++i) {
- SplitAnalysis::BlockInfo &BI = SA->LiveBlocks[i];
+ for (unsigned i = 0; i != UseBlocks.size(); ++i) {
+ const SplitAnalysis::BlockInfo &BI = UseBlocks[i];
bool RegIn = LiveBundles[Bundles->getBundle(BI.MBB->getNumber(), 0)];
bool RegOut = LiveBundles[Bundles->getBundle(BI.MBB->getNumber(), 1)];
Intf.moveToBlock(BI.MBB->getNumber());
DEBUG(dbgs() << "EB#" << Bundles->getBundle(BI.MBB->getNumber(), 0)
<< " -> BB#" << BI.MBB->getNumber() << " [" << Start << ';'
- << BI.LastSplitPoint << '-' << Stop << ')');
+ << SA->getLastSplitPoint(BI.MBB->getNumber()) << '-' << Stop
+ << ')');
// Check interference entering the block.
if (!Intf.hasInterference()) {
// Block is interference-free.
DEBUG(dbgs() << ", no interference");
- if (!BI.Uses) {
- assert(BI.LiveThrough && "No uses, but not live through block?");
- // Block is live-through without interference.
- if (RegOut) {
- DEBUG(dbgs() << ", no uses, live-through.\n");
- SE->useIntv(Start, Stop);
- } else {
- DEBUG(dbgs() << ", no uses, stack-out.\n");
- SE->leaveIntvAtTop(*BI.MBB);
- }
- continue;
- }
if (!BI.LiveThrough) {
DEBUG(dbgs() << ", killed in block.\n");
SE->useIntv(Start, SE->leaveIntvAfter(BI.Kill));
continue;
}
if (!RegOut) {
+ SlotIndex LastSplitPoint = SA->getLastSplitPoint(BI.MBB->getNumber());
// Block is live-through, but exit bundle is on the stack.
// Spill immediately after the last use.
- if (BI.LastUse < BI.LastSplitPoint) {
+ if (BI.LastUse < LastSplitPoint) {
DEBUG(dbgs() << ", uses, stack-out.\n");
SE->useIntv(Start, SE->leaveIntvAfter(BI.LastUse));
continue;
// The last use is after the last split point, it is probably an
// indirect jump.
DEBUG(dbgs() << ", uses at " << BI.LastUse << " after split point "
- << BI.LastSplitPoint << ", stack-out.\n");
- SlotIndex SegEnd = SE->leaveIntvBefore(BI.LastSplitPoint);
+ << LastSplitPoint << ", stack-out.\n");
+ SlotIndex SegEnd = SE->leaveIntvBefore(LastSplitPoint);
SE->useIntv(Start, SegEnd);
// Run a double interval from the split to the last use.
// This makes it possible to spill the complement without affecting the
continue;
}
- if (!BI.Uses) {
- // No uses in block, avoid interference by spilling as soon as possible.
- DEBUG(dbgs() << ", no uses.\n");
- SlotIndex SegEnd = SE->leaveIntvAtTop(*BI.MBB);
- assert(SegEnd <= Intf.first() && "Couldn't avoid interference");
- continue;
- }
if (Intf.first().getBaseIndex() > BI.FirstUse) {
// There are interference-free uses at the beginning of the block.
// Find the last use that can get the register.
assert(SegEnd <= Intf.first() && "Couldn't avoid interference");
}
+ // Handle live-through blocks.
+ for (unsigned i = 0, e = Cand.ActiveBlocks.size(); i != e; ++i) {
+ unsigned Number = Cand.ActiveBlocks[i];
+ bool RegIn = LiveBundles[Bundles->getBundle(Number, 0)];
+ bool RegOut = LiveBundles[Bundles->getBundle(Number, 1)];
+ DEBUG(dbgs() << "Live through BB#" << Number << '\n');
+ if (RegIn && RegOut) {
+ Intf.moveToBlock(Number);
+ if (!Intf.hasInterference()) {
+ SE->useIntv(Indexes->getMBBStartIdx(Number),
+ Indexes->getMBBEndIdx(Number));
+ continue;
+ }
+ }
+ MachineBasicBlock *MBB = MF->getBlockNumbered(Number);
+ if (RegIn)
+ SE->leaveIntvAtTop(*MBB);
+ if (RegOut)
+ SE->enterIntvAtEnd(*MBB);
+ }
+
SE->closeIntv();
// FIXME: Should we be more aggressive about splitting the stack region into
unsigned RAGreedy::tryRegionSplit(LiveInterval &VirtReg, AllocationOrder &Order,
SmallVectorImpl<LiveInterval*> &NewVRegs) {
- BitVector LiveBundles, BestBundles;
float BestCost = 0;
- unsigned BestReg = 0;
+ const unsigned NoCand = ~0u;
+ unsigned BestCand = NoCand;
Order.rewind();
for (unsigned Cand = 0; unsigned PhysReg = Order.next(); ++Cand) {
if (GlobalCand.size() <= Cand)
GlobalCand.resize(Cand+1);
- GlobalCand[Cand].PhysReg = PhysReg;
+ GlobalCand[Cand].reset(PhysReg);
- float Cost = calcSplitConstraints(PhysReg);
+ SpillPlacer->prepare(GlobalCand[Cand].LiveBundles);
+ float Cost;
+ InterferenceCache::Cursor Intf(IntfCache, PhysReg);
+ if (!addSplitConstraints(Intf, Cost)) {
+ DEBUG(dbgs() << PrintReg(PhysReg, TRI) << "\tno positive bundles\n");
+ continue;
+ }
DEBUG(dbgs() << PrintReg(PhysReg, TRI) << "\tstatic = " << Cost);
- if (BestReg && Cost >= BestCost) {
- DEBUG(dbgs() << " higher.\n");
+ if (BestCand != NoCand && Cost >= BestCost) {
+ DEBUG(dbgs() << " worse than "
+ << PrintReg(GlobalCand[BestCand].PhysReg, TRI) << '\n');
continue;
}
+ growRegion(GlobalCand[Cand], Intf);
+
+ SpillPlacer->finish();
- SpillPlacer->placeSpills(SplitConstraints, LiveBundles);
// No live bundles, defer to splitSingleBlocks().
- if (!LiveBundles.any()) {
+ if (!GlobalCand[Cand].LiveBundles.any()) {
DEBUG(dbgs() << " no bundles.\n");
continue;
}
- Cost += calcGlobalSplitCost(LiveBundles);
+ Cost += calcGlobalSplitCost(GlobalCand[Cand], Intf);
DEBUG({
dbgs() << ", total = " << Cost << " with bundles";
- for (int i = LiveBundles.find_first(); i>=0; i = LiveBundles.find_next(i))
+ for (int i = GlobalCand[Cand].LiveBundles.find_first(); i>=0;
+ i = GlobalCand[Cand].LiveBundles.find_next(i))
dbgs() << " EB#" << i;
dbgs() << ".\n";
});
- if (!BestReg || Cost < BestCost) {
- BestReg = PhysReg;
+ if (BestCand == NoCand || Cost < BestCost) {
+ BestCand = Cand;
BestCost = 0.98f * Cost; // Prevent rounding effects.
- BestBundles.swap(LiveBundles);
}
}
- if (!BestReg)
+ if (BestCand == NoCand)
return 0;
- splitAroundRegion(VirtReg, BestReg, BestBundles, NewVRegs);
- setStage(NewVRegs.begin(), NewVRegs.end(), RS_Region);
+ splitAroundRegion(VirtReg, GlobalCand[BestCand], NewVRegs);
+ setStage(NewVRegs.begin(), NewVRegs.end(), RS_Global);
return 0;
}
///
void RAGreedy::calcGapWeights(unsigned PhysReg,
SmallVectorImpl<float> &GapWeight) {
- assert(SA->LiveBlocks.size() == 1 && "Not a local interval");
- const SplitAnalysis::BlockInfo &BI = SA->LiveBlocks.front();
+ assert(SA->getUseBlocks().size() == 1 && "Not a local interval");
+ const SplitAnalysis::BlockInfo &BI = SA->getUseBlocks().front();
const SmallVectorImpl<SlotIndex> &Uses = SA->UseSlots;
const unsigned NumGaps = Uses.size()-1;
///
unsigned RAGreedy::tryLocalSplit(LiveInterval &VirtReg, AllocationOrder &Order,
SmallVectorImpl<LiveInterval*> &NewVRegs) {
- assert(SA->LiveBlocks.size() == 1 && "Not a local interval");
- const SplitAnalysis::BlockInfo &BI = SA->LiveBlocks.front();
+ assert(SA->getUseBlocks().size() == 1 && "Not a local interval");
+ const SplitAnalysis::BlockInfo &BI = SA->getUseBlocks().front();
// Note that it is possible to have an interval that is live-in or live-out
// while only covering a single block - A phi-def can use undef values from
// Don't iterate global splitting.
// Move straight to spilling if this range was produced by a global split.
- LiveRangeStage Stage = getStage(VirtReg);
- if (Stage >= RS_Block)
+ if (getStage(VirtReg) >= RS_Global)
return 0;
SA->analyze(&VirtReg);
// First try to split around a region spanning multiple blocks.
- if (Stage < RS_Region) {
- unsigned PhysReg = tryRegionSplit(VirtReg, Order, NewVRegs);
- if (PhysReg || !NewVRegs.empty())
- return PhysReg;
- }
+ unsigned PhysReg = tryRegionSplit(VirtReg, Order, NewVRegs);
+ if (PhysReg || !NewVRegs.empty())
+ return PhysReg;
// Then isolate blocks with multiple uses.
- if (Stage < RS_Block) {
- SplitAnalysis::BlockPtrSet Blocks;
- if (SA->getMultiUseBlocks(Blocks)) {
- LiveRangeEdit LREdit(VirtReg, NewVRegs, this);
- SE->reset(LREdit);
- SE->splitSingleBlocks(Blocks);
- setStage(NewVRegs.begin(), NewVRegs.end(), RS_Block);
- if (VerifyEnabled)
- MF->verify(this, "After splitting live range around basic blocks");
- }
+ SplitAnalysis::BlockPtrSet Blocks;
+ if (SA->getMultiUseBlocks(Blocks)) {
+ LiveRangeEdit LREdit(VirtReg, NewVRegs, this);
+ SE->reset(LREdit);
+ SE->splitSingleBlocks(Blocks);
+ setStage(NewVRegs.begin(), NewVRegs.end(), RS_Global);
+ if (VerifyEnabled)
+ MF->verify(this, "After splitting live range around basic blocks");
}
// Don't assign any physregs.
VRM->rewrite(Indexes);
}
+ // Write out new DBG_VALUE instructions.
+ getAnalysis<LiveDebugVariables>().emitDebugValues(VRM);
+
// The pass output is in VirtRegMap. Release all the transient data.
releaseMemory();
projects / oota-llvm.git / blobdiff