//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "regalloc"
-#include "LiveIntervalUnion.h"
#include "RegAllocBase.h"
+#include "LiveDebugVariables.h"
+#include "LiveIntervalUnion.h"
+#include "LiveRangeEdit.h"
#include "RenderMachineFunction.h"
#include "Spiller.h"
#include "VirtRegMap.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/RegAllocRegistry.h"
-#include "llvm/CodeGen/RegisterCoalescer.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Target/TargetRegisterInfo.h"
{
// context
MachineFunction *MF;
- BitVector ReservedRegs;
// analyses
LiveStacks *LS;
} // end anonymous namespace
RABasic::RABasic(): MachineFunctionPass(ID) {
+ initializeLiveDebugVariablesPass(*PassRegistry::getPassRegistry());
initializeLiveIntervalsPass(*PassRegistry::getPassRegistry());
initializeSlotIndexesPass(*PassRegistry::getPassRegistry());
initializeStrongPHIEliminationPass(*PassRegistry::getPassRegistry());
- initializeRegisterCoalescerAnalysisGroup(*PassRegistry::getPassRegistry());
+ initializeRegisterCoalescerPass(*PassRegistry::getPassRegistry());
initializeCalculateSpillWeightsPass(*PassRegistry::getPassRegistry());
initializeLiveStacksPass(*PassRegistry::getPassRegistry());
initializeMachineDominatorTreePass(*PassRegistry::getPassRegistry());
AU.addPreserved<AliasAnalysis>();
AU.addRequired<LiveIntervals>();
AU.addPreserved<SlotIndexes>();
+ AU.addRequired<LiveDebugVariables>();
+ AU.addPreserved<LiveDebugVariables>();
if (StrongPHIElim)
AU.addRequiredID(StrongPHIEliminationID);
- AU.addRequiredTransitive<RegisterCoalescer>();
+ AU.addRequiredTransitiveID(RegisterCoalescerPassID);
AU.addRequired<CalculateSpillWeights>();
AU.addRequired<LiveStacks>();
AU.addPreserved<LiveStacks>();
MRI = &vrm.getRegInfo();
VRM = &vrm;
LIS = &lis;
- PhysReg2LiveUnion.init(UnionAllocator, TRI->getNumRegs());
- // Cache an interferece query for each physical reg
- Queries.reset(new LiveIntervalUnion::Query[PhysReg2LiveUnion.numRegs()]);
+ RegClassInfo.runOnMachineFunction(vrm.getMachineFunction());
+
+ const unsigned NumRegs = TRI->getNumRegs();
+ if (NumRegs != PhysReg2LiveUnion.numRegs()) {
+ PhysReg2LiveUnion.init(UnionAllocator, NumRegs);
+ // Cache an interferece query for each physical reg
+ Queries.reset(new LiveIntervalUnion::Query[PhysReg2LiveUnion.numRegs()]);
+ }
}
void RegAllocBase::LiveUnionArray::clear() {
}
void RegAllocBase::releaseMemory() {
- PhysReg2LiveUnion.clear();
+ for (unsigned r = 0, e = PhysReg2LiveUnion.numRegs(); r != e; ++r)
+ PhysReg2LiveUnion[r].clear();
}
// Visit all the live registers. If they are already assigned to a physical
// register, unify them with the corresponding LiveIntervalUnion, otherwise push
// them on the priority queue for later assignment.
void RegAllocBase::seedLiveRegs() {
+ NamedRegionTimer T("Seed Live Regs", TimerGroupName, TimePassesIsEnabled);
for (LiveIntervals::iterator I = LIS->begin(), E = LIS->end(); I != E; ++I) {
unsigned RegNum = I->first;
LiveInterval &VirtReg = *I->second;
<< " to " << PrintReg(PhysReg, TRI) << '\n');
assert(!VRM->hasPhys(VirtReg.reg) && "Duplicate VirtReg assignment");
VRM->assignVirt2Phys(VirtReg.reg, PhysReg);
+ MRI->setPhysRegUsed(PhysReg);
PhysReg2LiveUnion[PhysReg].unify(VirtReg);
++NumAssigned;
}
// Continue assigning vregs one at a time to available physical registers.
while (LiveInterval *VirtReg = dequeue()) {
+ assert(!VRM->hasPhys(VirtReg->reg) && "Register already assigned");
+
+ // Unused registers can appear when the spiller coalesces snippets.
+ if (MRI->reg_nodbg_empty(VirtReg->reg)) {
+ DEBUG(dbgs() << "Dropping unused " << *VirtReg << '\n');
+ LIS->removeInterval(VirtReg->reg);
+ continue;
+ }
+
+ // Invalidate all interference queries, live ranges could have changed.
+ invalidateVirtRegs();
+
// selectOrSplit requests the allocator to return an available physical
// register if possible and populate a list of new live intervals that
// result from splitting.
VirtRegVec SplitVRegs;
unsigned AvailablePhysReg = selectOrSplit(*VirtReg, SplitVRegs);
+ if (AvailablePhysReg == ~0u) {
+ // selectOrSplit failed to find a register!
+ const char *Msg = "ran out of registers during register allocation";
+ // Probably caused by an inline asm.
+ MachineInstr *MI;
+ for (MachineRegisterInfo::reg_iterator I = MRI->reg_begin(VirtReg->reg);
+ (MI = I.skipInstruction());)
+ if (MI->isInlineAsm())
+ break;
+ if (MI)
+ MI->emitError(Msg);
+ else
+ report_fatal_error(Msg);
+ // Keep going after reporting the error.
+ VRM->assignVirt2Phys(VirtReg->reg,
+ RegClassInfo.getOrder(MRI->getRegClass(VirtReg->reg)).front());
+ continue;
+ }
+
if (AvailablePhysReg)
assign(*VirtReg, AvailablePhysReg);
for (VirtRegVec::iterator I = SplitVRegs.begin(), E = SplitVRegs.end();
I != E; ++I) {
LiveInterval *SplitVirtReg = *I;
- if (SplitVirtReg->empty()) continue;
+ assert(!VRM->hasPhys(SplitVirtReg->reg) && "Register already assigned");
+ if (MRI->reg_nodbg_empty(SplitVirtReg->reg)) {
+ DEBUG(dbgs() << "not queueing unused " << *SplitVirtReg << '\n');
+ LIS->removeInterval(SplitVirtReg->reg);
+ continue;
+ }
DEBUG(dbgs() << "queuing new interval: " << *SplitVirtReg << "\n");
assert(TargetRegisterInfo::isVirtualRegister(SplitVirtReg->reg) &&
"expect split value in virtual register");
unassign(SpilledVReg, PhysReg);
// Spill the extracted interval.
- spiller().spill(&SpilledVReg, SplitVRegs, &PendingSpills);
+ LiveRangeEdit LRE(SpilledVReg, SplitVRegs, 0, &PendingSpills);
+ spiller().spill(LRE);
}
// After extracting segments, the query's results are invalid. But keep the
// contents valid until we're done accessing pendingSpills.
// Add newly allocated physical registers to the MBB live in sets.
void RegAllocBase::addMBBLiveIns(MachineFunction *MF) {
NamedRegionTimer T("MBB Live Ins", TimerGroupName, TimePassesIsEnabled);
- typedef SmallVector<MachineBasicBlock*, 8> MBBVec;
- MBBVec liveInMBBs;
- MachineBasicBlock &entryMBB = *MF->begin();
+ SlotIndexes *Indexes = LIS->getSlotIndexes();
+ if (MF->size() <= 1)
+ return;
+ LiveIntervalUnion::SegmentIter SI;
for (unsigned PhysReg = 0; PhysReg < PhysReg2LiveUnion.numRegs(); ++PhysReg) {
LiveIntervalUnion &LiveUnion = PhysReg2LiveUnion[PhysReg];
if (LiveUnion.empty())
continue;
- for (LiveIntervalUnion::SegmentIter SI = LiveUnion.begin(); SI.valid();
- ++SI) {
-
- // Find the set of basic blocks which this range is live into...
- liveInMBBs.clear();
- if (!LIS->findLiveInMBBs(SI.start(), SI.stop(), liveInMBBs)) continue;
-
- // And add the physreg for this interval to their live-in sets.
- for (MBBVec::iterator I = liveInMBBs.begin(), E = liveInMBBs.end();
- I != E; ++I) {
- MachineBasicBlock *MBB = *I;
- if (MBB == &entryMBB) continue;
- if (MBB->isLiveIn(PhysReg)) continue;
- MBB->addLiveIn(PhysReg);
- }
+ DEBUG(dbgs() << PrintReg(PhysReg, TRI) << " live-in:");
+ MachineFunction::iterator MBB = llvm::next(MF->begin());
+ MachineFunction::iterator MFE = MF->end();
+ SlotIndex Start, Stop;
+ tie(Start, Stop) = Indexes->getMBBRange(MBB);
+ SI.setMap(LiveUnion.getMap());
+ SI.find(Start);
+ while (SI.valid()) {
+ if (SI.start() <= Start) {
+ if (!MBB->isLiveIn(PhysReg))
+ MBB->addLiveIn(PhysReg);
+ DEBUG(dbgs() << "\tBB#" << MBB->getNumber() << ':'
+ << PrintReg(SI.value()->reg, TRI));
+ } else if (SI.start() > Stop)
+ MBB = Indexes->getMBBFromIndex(SI.start().getPrevIndex());
+ if (++MBB == MFE)
+ break;
+ tie(Start, Stop) = Indexes->getMBBRange(MBB);
+ SI.advanceTo(Start);
}
+ DEBUG(dbgs() << '\n');
}
}
SmallVector<unsigned, 8> PhysRegSpillCands;
// Check for an available register in this class.
- const TargetRegisterClass *TRC = MRI->getRegClass(VirtReg.reg);
-
- for (TargetRegisterClass::iterator I = TRC->allocation_order_begin(*MF),
- E = TRC->allocation_order_end(*MF);
- I != E; ++I) {
-
+ ArrayRef<unsigned> Order =
+ RegClassInfo.getOrder(MRI->getRegClass(VirtReg.reg));
+ for (ArrayRef<unsigned>::iterator I = Order.begin(), E = Order.end(); I != E;
+ ++I) {
unsigned PhysReg = *I;
- if (ReservedRegs.test(PhysReg)) continue;
// Check interference and as a side effect, intialize queries for this
// VirtReg and its aliases.
// Found an available register.
return PhysReg;
}
+ Queries[interfReg].collectInterferingVRegs(1);
LiveInterval *interferingVirtReg =
- Queries[interfReg].firstInterference().liveUnionPos().value();
+ Queries[interfReg].interferingVRegs().front();
// The current VirtReg must either be spillable, or one of its interferences
// must have less spill weight.
// Tell the caller to allocate to this newly freed physical register.
return *PhysRegI;
}
+
// No other spill candidates were found, so spill the current VirtReg.
DEBUG(dbgs() << "spilling: " << VirtReg << '\n');
- spiller().spill(&VirtReg, SplitVRegs, 0);
+ if (!VirtReg.isSpillable())
+ return ~0u;
+ LiveRangeEdit LRE(VirtReg, SplitVRegs);
+ spiller().spill(LRE);
// The live virtual register requesting allocation was spilled, so tell
// the caller not to allocate anything during this round.
DEBUG(RMF = &getAnalysis<RenderMachineFunction>());
RegAllocBase::init(getAnalysis<VirtRegMap>(), getAnalysis<LiveIntervals>());
-
- ReservedRegs = TRI->getReservedRegs(*MF);
-
- SpillerInstance.reset(createSpiller(*this, *MF, *VRM));
+ SpillerInstance.reset(createInlineSpiller(*this, *MF, *VRM));
allocatePhysRegs();
// Run rewriter
VRM->rewrite(LIS->getSlotIndexes());
+ // Write out new DBG_VALUE instructions.
+ getAnalysis<LiveDebugVariables>().emitDebugValues(VRM);
+
// The pass output is in VirtRegMap. Release all the transient data.
releaseMemory();