//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "regalloc"
+#include "LiveDebugVariables.h"
+#include "LiveRangeEdit.h"
#include "VirtRegMap.h"
#include "VirtRegRewriter.h"
#include "Spiller.h"
+#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Function.h"
#include "llvm/CodeGen/CalcSpillWeights.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
-#include "llvm/CodeGen/LiveStackAnalysis.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineLoopInfo.h"
// pressure, it can caused fewer GPRs to be held in the queue.
static cl::opt<unsigned>
NumRecentlyUsedRegs("linearscan-skip-count",
- cl::desc("Number of registers for linearscan to remember to skip."),
+ cl::desc("Number of registers for linearscan to remember"
+ "to skip."),
cl::init(0),
cl::Hidden);
-
+
struct RALinScan : public MachineFunctionPass {
static char ID;
- RALinScan() : MachineFunctionPass(&ID) {
+ RALinScan() : MachineFunctionPass(ID) {
+ initializeLiveDebugVariablesPass(*PassRegistry::getPassRegistry());
+ initializeLiveIntervalsPass(*PassRegistry::getPassRegistry());
+ initializeStrongPHIEliminationPass(*PassRegistry::getPassRegistry());
+ initializeRegisterCoalescerAnalysisGroup(
+ *PassRegistry::getPassRegistry());
+ initializeCalculateSpillWeightsPass(*PassRegistry::getPassRegistry());
+ initializePreAllocSplittingPass(*PassRegistry::getPassRegistry());
+ initializeLiveStacksPass(*PassRegistry::getPassRegistry());
+ initializeMachineDominatorTreePass(*PassRegistry::getPassRegistry());
+ initializeMachineLoopInfoPass(*PassRegistry::getPassRegistry());
+ initializeVirtRegMapPass(*PassRegistry::getPassRegistry());
+ initializeMachineDominatorTreePass(*PassRegistry::getPassRegistry());
+
// Initialize the queue to record recently-used registers.
if (NumRecentlyUsedRegs > 0)
RecentRegs.resize(NumRecentlyUsedRegs, 0);
const TargetRegisterInfo* tri_;
const TargetInstrInfo* tii_;
BitVector allocatableRegs_;
+ BitVector reservedRegs_;
LiveIntervals* li_;
- LiveStacks* ls_;
- const MachineLoopInfo *loopInfo;
+ MachineLoopInfo *loopInfo;
/// handled_ - Intervals are added to the handled_ set in the order of their
/// start value. This is uses for backtracking.
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesCFG();
+ AU.addRequired<AliasAnalysis>();
+ AU.addPreserved<AliasAnalysis>();
AU.addRequired<LiveIntervals>();
AU.addPreserved<SlotIndexes>();
if (StrongPHIElim)
AU.addRequired<CalculateSpillWeights>();
if (PreSplitIntervals)
AU.addRequiredID(PreAllocSplittingID);
- AU.addRequired<LiveStacks>();
- AU.addPreserved<LiveStacks>();
+ AU.addRequiredID(LiveStacksID);
+ AU.addPreservedID(LiveStacksID);
AU.addRequired<MachineLoopInfo>();
AU.addPreserved<MachineLoopInfo>();
AU.addRequired<VirtRegMap>();
AU.addPreserved<VirtRegMap>();
+ AU.addRequired<LiveDebugVariables>();
+ AU.addPreserved<LiveDebugVariables>();
+ AU.addRequiredID(MachineDominatorsID);
AU.addPreservedID(MachineDominatorsID);
MachineFunctionPass::getAnalysisUsage(AU);
}
SmallVector<LiveInterval*, 8> &SpillIntervals);
/// attemptTrivialCoalescing - If a simple interval is defined by a copy,
- /// try allocate the definition the same register as the source register
- /// if the register is not defined during live time of the interval. This
- /// eliminate a copy. This is used to coalesce copies which were not
+ /// try to allocate the definition to the same register as the source,
+ /// if the register is not defined during the life time of the interval.
+ /// This eliminates a copy, and is used to coalesce copies which were not
/// coalesced away before allocation either due to dest and src being in
/// different register classes or because the coalescer was overly
/// conservative.
bool Error = false;
for (unsigned i = 0, e = tri_->getNumRegs(); i != e; ++i) {
if (regUse_[i] != 0) {
- errs() << tri_->getName(i) << " is still in use!\n";
+ dbgs() << tri_->getName(i) << " is still in use!\n";
Error = true;
}
}
SmallVector<unsigned, 256> &inactiveCounts,
bool SkipDGRegs);
- /// assignVirt2StackSlot - assigns this virtual register to a
- /// stack slot. returns the stack slot
- int assignVirt2StackSlot(unsigned virtReg);
+ /// getFirstNonReservedPhysReg - return the first non-reserved physical
+ /// register in the register class.
+ unsigned getFirstNonReservedPhysReg(const TargetRegisterClass *RC) {
+ TargetRegisterClass::iterator aoe = RC->allocation_order_end(*mf_);
+ TargetRegisterClass::iterator i = RC->allocation_order_begin(*mf_);
+ while (i != aoe && reservedRegs_.test(*i))
+ ++i;
+ assert(i != aoe && "All registers reserved?!");
+ return *i;
+ }
void ComputeRelatedRegClasses();
void printIntervals(const char* const str, ItTy i, ItTy e) const {
DEBUG({
if (str)
- errs() << str << " intervals:\n";
+ dbgs() << str << " intervals:\n";
for (; i != e; ++i) {
- errs() << "\t" << *i->first << " -> ";
+ dbgs() << '\t' << *i->first << " -> ";
unsigned reg = i->first->reg;
if (TargetRegisterInfo::isVirtualRegister(reg))
reg = vrm_->getPhys(reg);
- errs() << tri_->getName(reg) << '\n';
+ dbgs() << tri_->getName(reg) << '\n';
}
});
}
char RALinScan::ID = 0;
}
-static RegisterPass<RALinScan>
-X("linearscan-regalloc", "Linear Scan Register Allocator");
+INITIALIZE_PASS_BEGIN(RALinScan, "linearscan-regalloc",
+ "Linear Scan Register Allocator", false, false)
+INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
+INITIALIZE_PASS_DEPENDENCY(StrongPHIElimination)
+INITIALIZE_PASS_DEPENDENCY(CalculateSpillWeights)
+INITIALIZE_PASS_DEPENDENCY(PreAllocSplitting)
+INITIALIZE_PASS_DEPENDENCY(LiveStacks)
+INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
+INITIALIZE_PASS_DEPENDENCY(VirtRegMap)
+INITIALIZE_AG_DEPENDENCY(RegisterCoalescer)
+INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
+INITIALIZE_PASS_END(RALinScan, "linearscan-regalloc",
+ "Linear Scan Register Allocator", false, false)
void RALinScan::ComputeRelatedRegClasses() {
// First pass, add all reg classes to the union, and determine at least one
for (TargetRegisterClass::iterator I = (*RCI)->begin(), E = (*RCI)->end();
I != E; ++I) {
HasAliases = HasAliases || *tri_->getAliasSet(*I) != 0;
-
+
const TargetRegisterClass *&PRC = OneClassForEachPhysReg[*I];
if (PRC) {
// Already processed this register. Just make sure we know that
}
}
}
-
+
// Second pass, now that we know conservatively what register classes each reg
// belongs to, add info about aliases. We don't need to do this for targets
// without register aliases.
for (DenseMap<unsigned, const TargetRegisterClass*>::iterator
I = OneClassForEachPhysReg.begin(), E = OneClassForEachPhysReg.end();
I != E; ++I)
- for (const unsigned *AS = tri_->getAliasSet(I->first); *AS; ++AS)
- RelatedRegClasses.unionSets(I->second, OneClassForEachPhysReg[*AS]);
+ for (const unsigned *AS = tri_->getAliasSet(I->first); *AS; ++AS) {
+ const TargetRegisterClass *AliasClass =
+ OneClassForEachPhysReg.lookup(*AS);
+ if (AliasClass)
+ RelatedRegClasses.unionSets(I->second, AliasClass);
+ }
}
/// attemptTrivialCoalescing - If a simple interval is defined by a copy, try
const LiveRange &range = cur.ranges.front();
VNInfo *vni = range.valno;
- if (vni->isUnused())
+ if (vni->isUnused() || !vni->def.isValid())
return Reg;
unsigned CandReg;
{
MachineInstr *CopyMI;
- unsigned SrcReg, DstReg, SrcSubReg, DstSubReg;
- if (vni->def != SlotIndex() && vni->isDefAccurate() &&
- (CopyMI = li_->getInstructionFromIndex(vni->def)) &&
- tii_->isMoveInstr(*CopyMI, SrcReg, DstReg, SrcSubReg, DstSubReg))
+ if ((CopyMI = li_->getInstructionFromIndex(vni->def)) && CopyMI->isCopy())
// Defined by a copy, try to extend SrcReg forward
- CandReg = SrcReg;
+ CandReg = CopyMI->getOperand(1).getReg();
else if (TrivCoalesceEnds &&
- (CopyMI =
- li_->getInstructionFromIndex(range.end.getBaseIndex())) &&
- tii_->isMoveInstr(*CopyMI, SrcReg, DstReg, SrcSubReg, DstSubReg) &&
- cur.reg == SrcReg)
+ (CopyMI = li_->getInstructionFromIndex(range.end.getBaseIndex())) &&
+ CopyMI->isCopy() && cur.reg == CopyMI->getOperand(1).getReg())
// Only used by a copy, try to extend DstReg backwards
- CandReg = DstReg;
+ CandReg = CopyMI->getOperand(0).getReg();
else
return Reg;
+
+ // If the target of the copy is a sub-register then don't coalesce.
+ if(CopyMI->getOperand(0).getSubReg())
+ return Reg;
}
if (TargetRegisterInfo::isVirtualRegister(CandReg)) {
return Reg;
// Try to coalesce.
- DEBUG(errs() << "Coalescing: " << cur << " -> " << tri_->getName(CandReg)
+ DEBUG(dbgs() << "Coalescing: " << cur << " -> " << tri_->getName(CandReg)
<< '\n');
vrm_->clearVirt(cur.reg);
vrm_->assignVirt2Phys(cur.reg, CandReg);
tri_ = tm_->getRegisterInfo();
tii_ = tm_->getInstrInfo();
allocatableRegs_ = tri_->getAllocatableSet(fn);
+ reservedRegs_ = tri_->getReservedRegs(fn);
li_ = &getAnalysis<LiveIntervals>();
- ls_ = &getAnalysis<LiveStacks>();
loopInfo = &getAnalysis<MachineLoopInfo>();
// We don't run the coalescer here because we have no reason to
vrm_ = &getAnalysis<VirtRegMap>();
if (!rewriter_.get()) rewriter_.reset(createVirtRegRewriter());
-
- spiller_.reset(createSpiller(mf_, li_, loopInfo, vrm_));
-
+
+ spiller_.reset(createSpiller(*this, *mf_, *vrm_));
+
initIntervalSets();
linearScan();
// Rewrite spill code and update the PhysRegsUsed set.
rewriter_->runOnMachineFunction(*mf_, *vrm_, li_);
+ // Write out new DBG_VALUE instructions.
+ getAnalysis<LiveDebugVariables>().emitDebugValues(vrm_);
+
assert(unhandled_.empty() && "Unhandled live intervals remain!");
finalizeRegUses();
void RALinScan::linearScan() {
// linear scan algorithm
DEBUG({
- errs() << "********** LINEAR SCAN **********\n"
- << "********** Function: "
+ dbgs() << "********** LINEAR SCAN **********\n"
+ << "********** Function: "
<< mf_->getFunction()->getName() << '\n';
printIntervals("fixed", fixed_.begin(), fixed_.end());
});
LiveInterval* cur = unhandled_.top();
unhandled_.pop();
++NumIters;
- DEBUG(errs() << "\n*** CURRENT ***: " << *cur << '\n');
+ DEBUG(dbgs() << "\n*** CURRENT ***: " << *cur << '\n');
assert(!cur->empty() && "Empty interval in unhandled set.");
while (!active_.empty()) {
IntervalPtr &IP = active_.back();
unsigned reg = IP.first->reg;
- DEBUG(errs() << "\tinterval " << *IP.first << " expired\n");
+ DEBUG(dbgs() << "\tinterval " << *IP.first << " expired\n");
assert(TargetRegisterInfo::isVirtualRegister(reg) &&
"Can only allocate virtual registers!");
reg = vrm_->getPhys(reg);
DEBUG({
for (IntervalPtrs::reverse_iterator
i = inactive_.rbegin(); i != inactive_.rend(); ++i)
- errs() << "\tinterval " << *i->first << " expired\n";
+ dbgs() << "\tinterval " << *i->first << " expired\n";
});
inactive_.clear();
}
}
- DEBUG(errs() << *vrm_);
+ DEBUG(dbgs() << *vrm_);
// Look for physical registers that end up not being allocated even though
// register allocator had to spill other registers in its register class.
- if (ls_->getNumIntervals() == 0)
- return;
if (!vrm_->FindUnusedRegisters(li_))
return;
}
/// to the inactive list.
void RALinScan::processActiveIntervals(SlotIndex CurPoint)
{
- DEBUG(errs() << "\tprocessing active intervals:\n");
+ DEBUG(dbgs() << "\tprocessing active intervals:\n");
for (unsigned i = 0, e = active_.size(); i != e; ++i) {
LiveInterval *Interval = active_[i].first;
IntervalPos = Interval->advanceTo(IntervalPos, CurPoint);
if (IntervalPos == Interval->end()) { // Remove expired intervals.
- DEBUG(errs() << "\t\tinterval " << *Interval << " expired\n");
+ DEBUG(dbgs() << "\t\tinterval " << *Interval << " expired\n");
assert(TargetRegisterInfo::isVirtualRegister(reg) &&
"Can only allocate virtual registers!");
reg = vrm_->getPhys(reg);
} else if (IntervalPos->start > CurPoint) {
// Move inactive intervals to inactive list.
- DEBUG(errs() << "\t\tinterval " << *Interval << " inactive\n");
+ DEBUG(dbgs() << "\t\tinterval " << *Interval << " inactive\n");
assert(TargetRegisterInfo::isVirtualRegister(reg) &&
"Can only allocate virtual registers!");
reg = vrm_->getPhys(reg);
/// ones to the active list.
void RALinScan::processInactiveIntervals(SlotIndex CurPoint)
{
- DEBUG(errs() << "\tprocessing inactive intervals:\n");
+ DEBUG(dbgs() << "\tprocessing inactive intervals:\n");
for (unsigned i = 0, e = inactive_.size(); i != e; ++i) {
LiveInterval *Interval = inactive_[i].first;
IntervalPos = Interval->advanceTo(IntervalPos, CurPoint);
if (IntervalPos == Interval->end()) { // remove expired intervals.
- DEBUG(errs() << "\t\tinterval " << *Interval << " expired\n");
+ DEBUG(dbgs() << "\t\tinterval " << *Interval << " expired\n");
// Pop off the end of the list.
inactive_[i] = inactive_.back();
--i; --e;
} else if (IntervalPos->start <= CurPoint) {
// move re-activated intervals in active list
- DEBUG(errs() << "\t\tinterval " << *Interval << " active\n");
+ DEBUG(dbgs() << "\t\tinterval " << *Interval << " active\n");
assert(TargetRegisterInfo::isVirtualRegister(reg) &&
"Can only allocate virtual registers!");
reg = vrm_->getPhys(reg);
return IP.end();
}
-static void RevertVectorIteratorsTo(RALinScan::IntervalPtrs &V, SlotIndex Point){
+static void RevertVectorIteratorsTo(RALinScan::IntervalPtrs &V,
+ SlotIndex Point){
for (unsigned i = 0, e = V.size(); i != e; ++i) {
RALinScan::IntervalPtr &IP = V[i];
LiveInterval::iterator I = std::upper_bound(IP.first->begin(),
}
}
-/// addStackInterval - Create a LiveInterval for stack if the specified live
-/// interval has been spilled.
-static void addStackInterval(LiveInterval *cur, LiveStacks *ls_,
- LiveIntervals *li_,
- MachineRegisterInfo* mri_, VirtRegMap &vrm_) {
- int SS = vrm_.getStackSlot(cur->reg);
- if (SS == VirtRegMap::NO_STACK_SLOT)
- return;
-
- const TargetRegisterClass *RC = mri_->getRegClass(cur->reg);
- LiveInterval &SI = ls_->getOrCreateInterval(SS, RC);
-
- VNInfo *VNI;
- if (SI.hasAtLeastOneValue())
- VNI = SI.getValNumInfo(0);
- else
- VNI = SI.getNextValue(SlotIndex(), 0, false,
- ls_->getVNInfoAllocator());
-
- LiveInterval &RI = li_->getInterval(cur->reg);
- // FIXME: This may be overly conservative.
- SI.MergeRangesInAsValue(RI, VNI);
-}
-
/// getConflictWeight - Return the number of conflicts between cur
/// live interval and defs and uses of Reg weighted by loop depthes.
static
float getConflictWeight(LiveInterval *cur, unsigned Reg, LiveIntervals *li_,
MachineRegisterInfo *mri_,
- const MachineLoopInfo *loopInfo) {
+ MachineLoopInfo *loopInfo) {
float Conflicts = 0;
for (MachineRegisterInfo::reg_iterator I = mri_->reg_begin(Reg),
E = mri_->reg_end(); I != E; ++I) {
MachineInstr *MI = &*I;
if (cur->liveAt(li_->getInstructionIndex(MI))) {
unsigned loopDepth = loopInfo->getLoopDepth(MI->getParent());
- Conflicts += powf(10.0f, (float)loopDepth);
+ Conflicts += std::pow(10.0f, (float)loopDepth);
}
}
return Conflicts;
SmallVector<LiveInterval*, 8> SLIs[3];
DEBUG({
- errs() << "\tConsidering " << NumCands << " candidates: ";
+ dbgs() << "\tConsidering " << NumCands << " candidates: ";
for (unsigned i = 0; i != NumCands; ++i)
- errs() << tri_->getName(Candidates[i].first) << " ";
- errs() << "\n";
+ dbgs() << tri_->getName(Candidates[i].first) << " ";
+ dbgs() << "\n";
});
-
+
// Calculate the number of conflicts of each candidate.
for (IntervalPtrs::iterator i = active_.begin(); i != active_.end(); ++i) {
unsigned Reg = i->first->reg;
const RALinScan &Allocator;
public:
- WeightCompare(const RALinScan &Alloc) : Allocator(Alloc) {};
+ WeightCompare(const RALinScan &Alloc) : Allocator(Alloc) {}
typedef std::pair<unsigned, float> RegWeightPair;
bool operator()(const RegWeightPair &LHS, const RegWeightPair &RHS) const {
}
void RALinScan::DowngradeRegister(LiveInterval *li, unsigned Reg) {
- bool isNew = DowngradedRegs.insert(Reg);
- isNew = isNew; // Silence compiler warning.
- assert(isNew && "Multiple reloads holding the same register?");
- DowngradeMap.insert(std::make_pair(li->reg, Reg));
- for (const unsigned *AS = tri_->getAliasSet(Reg); *AS; ++AS) {
- isNew = DowngradedRegs.insert(*AS);
- isNew = isNew; // Silence compiler warning.
+ for (const unsigned *AS = tri_->getOverlaps(Reg); *AS; ++AS) {
+ bool isNew = DowngradedRegs.insert(*AS);
+ (void)isNew; // Silence compiler warning.
assert(isNew && "Multiple reloads holding the same register?");
DowngradeMap.insert(std::make_pair(li->reg, *AS));
}
/// assignRegOrStackSlotAtInterval - assign a register if one is available, or
/// spill.
void RALinScan::assignRegOrStackSlotAtInterval(LiveInterval* cur) {
- DEBUG(errs() << "\tallocating current interval: ");
+ const TargetRegisterClass *RC = mri_->getRegClass(cur->reg);
+ DEBUG(dbgs() << "\tallocating current interval from "
+ << RC->getName() << ": ");
// This is an implicitly defined live interval, just assign any register.
- const TargetRegisterClass *RC = mri_->getRegClass(cur->reg);
if (cur->empty()) {
unsigned physReg = vrm_->getRegAllocPref(cur->reg);
if (!physReg)
- physReg = *RC->allocation_order_begin(*mf_);
- DEBUG(errs() << tri_->getName(physReg) << '\n');
+ physReg = getFirstNonReservedPhysReg(RC);
+ DEBUG(dbgs() << tri_->getName(physReg) << '\n');
// Note the register is not really in use.
vrm_->assignVirt2Phys(cur->reg, physReg);
return;
// one, e.g. X86::mov32to32_. These move instructions are not coalescable.
if (!vrm_->getRegAllocPref(cur->reg) && cur->hasAtLeastOneValue()) {
VNInfo *vni = cur->begin()->valno;
- if ((vni->def != SlotIndex()) && !vni->isUnused() &&
- vni->isDefAccurate()) {
+ if (!vni->isUnused() && vni->def.isValid()) {
MachineInstr *CopyMI = li_->getInstructionFromIndex(vni->def);
- unsigned SrcReg, DstReg, SrcSubReg, DstSubReg;
- if (CopyMI &&
- tii_->isMoveInstr(*CopyMI, SrcReg, DstReg, SrcSubReg, DstSubReg)) {
+ if (CopyMI && CopyMI->isCopy()) {
+ unsigned DstSubReg = CopyMI->getOperand(0).getSubReg();
+ unsigned SrcReg = CopyMI->getOperand(1).getReg();
+ unsigned SrcSubReg = CopyMI->getOperand(1).getSubReg();
unsigned Reg = 0;
if (TargetRegisterInfo::isPhysicalRegister(SrcReg))
Reg = SrcReg;
assert(TargetRegisterInfo::isVirtualRegister(Reg) &&
"Can only allocate virtual registers!");
const TargetRegisterClass *RegRC = mri_->getRegClass(Reg);
- // If this is not in a related reg class to the register we're allocating,
+ // If this is not in a related reg class to the register we're allocating,
// don't check it.
if (RelatedRegClasses.getLeaderValue(RegRC) == RCLeader &&
cur->overlapsFrom(*i->first, i->second-1)) {
SpillWeightsToAdd.push_back(std::make_pair(Reg, i->first->weight));
}
}
-
+
// Speculatively check to see if we can get a register right now. If not,
// we know we won't be able to by adding more constraints. If so, we can
// check to see if it is valid. Doing an exhaustive search of the fixed_ list
SmallSet<unsigned, 8> RegAliases;
for (const unsigned *AS = tri_->getAliasSet(physReg); *AS; ++AS)
RegAliases.insert(*AS);
-
+
bool ConflictsWithFixed = false;
for (unsigned i = 0, e = fixed_.size(); i != e; ++i) {
IntervalPtr &IP = fixed_[i];
}
}
}
-
+
// Okay, the register picked by our speculative getFreePhysReg call turned
// out to be in use. Actually add all of the conflicting fixed registers to
// regUse_ so we can do an accurate query.
LiveInterval *I = IP.first;
const TargetRegisterClass *RegRC = OneClassForEachPhysReg[I->reg];
- if (RelatedRegClasses.getLeaderValue(RegRC) == RCLeader &&
+ if (RelatedRegClasses.getLeaderValue(RegRC) == RCLeader &&
I->endIndex() > StartPosition) {
LiveInterval::iterator II = I->advanceTo(IP.second, StartPosition);
IP.second = II;
physReg = getFreePhysReg(cur);
}
}
-
+
// Restore the physical register tracker, removing information about the
// future.
restoreRegUses();
-
+
// If we find a free register, we are done: assign this virtual to
// the free physical register and add this interval to the active
// list.
if (physReg) {
- DEBUG(errs() << tri_->getName(physReg) << '\n');
+ DEBUG(dbgs() << tri_->getName(physReg) << '\n');
+ assert(RC->contains(physReg) && "Invalid candidate");
vrm_->assignVirt2Phys(cur->reg, physReg);
addRegUse(physReg);
active_.push_back(std::make_pair(cur, cur->begin()));
UpgradeRegister(physReg);
if (LiveInterval *NextReloadLI = hasNextReloadInterval(cur)) {
// "Downgrade" physReg to try to keep physReg from being allocated until
- // the next reload from the same SS is allocated.
+ // the next reload from the same SS is allocated.
mri_->setRegAllocationHint(NextReloadLI->reg, 0, physReg);
DowngradeRegister(cur, physReg);
}
return;
}
- DEBUG(errs() << "no free registers\n");
+ DEBUG(dbgs() << "no free registers\n");
// Compile the spill weights into an array that is better for scanning.
std::vector<float> SpillWeights(tri_->getNumRegs(), 0.0f);
for (std::vector<std::pair<unsigned, float> >::iterator
I = SpillWeightsToAdd.begin(), E = SpillWeightsToAdd.end(); I != E; ++I)
updateSpillWeights(SpillWeights, I->first, I->second, RC);
-
+
// for each interval in active, update spill weights.
for (IntervalPtrs::const_iterator i = active_.begin(), e = active_.end();
i != e; ++i) {
reg = vrm_->getPhys(reg);
updateSpillWeights(SpillWeights, reg, i->first->weight, RC);
}
-
- DEBUG(errs() << "\tassigning stack slot at interval "<< *cur << ":\n");
+
+ DEBUG(dbgs() << "\tassigning stack slot at interval "<< *cur << ":\n");
// Find a register to spill.
float minWeight = HUGE_VALF;
e = RC->allocation_order_end(*mf_); i != e; ++i) {
unsigned reg = *i;
float regWeight = SpillWeights[reg];
- // Skip recently allocated registers.
+ // Don't even consider reserved regs.
+ if (reservedRegs_.test(reg))
+ continue;
+ // Skip recently allocated registers and reserved registers.
if (minWeight > regWeight && !isRecentlyUsed(reg))
Found = true;
RegsWeights.push_back(std::make_pair(reg, regWeight));
}
-
+
// If we didn't find a register that is spillable, try aliases?
if (!Found) {
for (TargetRegisterClass::iterator i = RC->allocation_order_begin(*mf_),
e = RC->allocation_order_end(*mf_); i != e; ++i) {
unsigned reg = *i;
+ if (reservedRegs_.test(reg))
+ continue;
// No need to worry about if the alias register size < regsize of RC.
// We are going to spill all registers that alias it anyway.
for (const unsigned* as = tri_->getAliasSet(reg); *as; ++as)
minWeight = RegsWeights[0].second;
if (minWeight == HUGE_VALF) {
// All registers must have inf weight. Just grab one!
- minReg = BestPhysReg ? BestPhysReg : *RC->allocation_order_begin(*mf_);
+ minReg = BestPhysReg ? BestPhysReg : getFirstNonReservedPhysReg(RC);
if (cur->weight == HUGE_VALF ||
li_->getApproximateInstructionCount(*cur) == 0) {
// Spill a physical register around defs and uses.
assignRegOrStackSlotAtInterval(cur);
} else {
assert(false && "Ran out of registers during register allocation!");
- llvm_report_error("Ran out of registers during register allocation!");
+ report_fatal_error("Ran out of registers during register allocation!");
}
return;
}
}
DEBUG({
- errs() << "\t\tregister(s) with min weight(s): ";
+ dbgs() << "\t\tregister(s) with min weight(s): ";
for (unsigned i = 0; i != LastCandidate; ++i)
- errs() << tri_->getName(RegsWeights[i].first)
+ dbgs() << tri_->getName(RegsWeights[i].first)
<< " (" << RegsWeights[i].second << ")\n";
});
// add any added intervals back to unhandled, and restart
// linearscan.
if (cur->weight != HUGE_VALF && cur->weight <= minWeight) {
- DEBUG(errs() << "\t\t\tspilling(c): " << *cur << '\n');
- SmallVector<LiveInterval*, 8> spillIs;
- std::vector<LiveInterval*> added;
-
- added = spiller_->spill(cur, spillIs);
+ DEBUG(dbgs() << "\t\t\tspilling(c): " << *cur << '\n');
+ SmallVector<LiveInterval*, 8> added;
+ LiveRangeEdit LRE(*cur, added);
+ spiller_->spill(LRE);
std::sort(added.begin(), added.end(), LISorter());
- addStackInterval(cur, ls_, li_, mri_, *vrm_);
if (added.empty())
return; // Early exit if all spills were folded.
// The earliest start of a Spilled interval indicates up to where
// in handled we need to roll back
- assert(!spillIs.empty() && "No spill intervals?");
+ assert(!spillIs.empty() && "No spill intervals?");
SlotIndex earliestStart = spillIs[0]->beginIndex();
-
+
// Spill live intervals of virtual regs mapped to the physical register we
// want to clear (and its aliases). We only spill those that overlap with the
// current interval as the rest do not affect its allocation. we also keep
// track of the earliest start of all spilled live intervals since this will
// mark our rollback point.
- std::vector<LiveInterval*> added;
+ SmallVector<LiveInterval*, 8> added;
while (!spillIs.empty()) {
LiveInterval *sli = spillIs.back();
spillIs.pop_back();
- DEBUG(errs() << "\t\t\tspilling(a): " << *sli << '\n');
+ DEBUG(dbgs() << "\t\t\tspilling(a): " << *sli << '\n');
if (sli->beginIndex() < earliestStart)
earliestStart = sli->beginIndex();
-
- std::vector<LiveInterval*> newIs;
- newIs = spiller_->spill(sli, spillIs, &earliestStart);
- addStackInterval(sli, ls_, li_, mri_, *vrm_);
- std::copy(newIs.begin(), newIs.end(), std::back_inserter(added));
+ LiveRangeEdit LRE(*sli, added, 0, &spillIs);
+ spiller_->spill(LRE);
spilled.insert(sli->reg);
}
- DEBUG(errs() << "\t\trolling back to: " << earliestStart << '\n');
+ // Include any added intervals in earliestStart.
+ for (unsigned i = 0, e = added.size(); i != e; ++i) {
+ SlotIndex SI = added[i]->beginIndex();
+ if (SI < earliestStart)
+ earliestStart = SI;
+ }
+
+ DEBUG(dbgs() << "\t\trolling back to: " << earliestStart << '\n');
// Scan handled in reverse order up to the earliest start of a
// spilled live interval and undo each one, restoring the state of
// If this interval starts before t we are done.
if (!i->empty() && i->beginIndex() < earliestStart)
break;
- DEBUG(errs() << "\t\t\tundo changes for: " << *i << '\n');
+ DEBUG(dbgs() << "\t\t\tundo changes for: " << *i << '\n');
handled_.pop_back();
// When undoing a live interval allocation we must know if it is active or
LiveInterval *HI = handled_[i];
if (!HI->expiredAt(earliestStart) &&
HI->expiredAt(cur->beginIndex())) {
- DEBUG(errs() << "\t\t\tundo changes for: " << *HI << '\n');
+ DEBUG(dbgs() << "\t\t\tundo changes for: " << *HI << '\n');
active_.push_back(std::make_pair(HI, HI->begin()));
assert(!TargetRegisterInfo::isPhysicalRegister(HI->reg));
addRegUse(vrm_->getPhys(HI->reg));
std::pair<unsigned, unsigned> Hint = mri_->getRegAllocationHint(cur->reg);
// Resolve second part of the hint (if possible) given the current allocation.
unsigned physReg = Hint.second;
- if (physReg &&
- TargetRegisterInfo::isVirtualRegister(physReg) && vrm_->hasPhys(physReg))
+ if (TargetRegisterInfo::isVirtualRegister(physReg) && vrm_->hasPhys(physReg))
physReg = vrm_->getPhys(physReg);
TargetRegisterClass::iterator I, E;
// Ignore "downgraded" registers.
if (SkipDGRegs && DowngradedRegs.count(Reg))
continue;
+ // Skip reserved registers.
+ if (reservedRegs_.test(Reg))
+ continue;
// Skip recently allocated registers.
if (isRegAvail(Reg) && !isRecentlyUsed(Reg)) {
FreeReg = Reg;
// Ignore "downgraded" registers.
if (SkipDGRegs && DowngradedRegs.count(Reg))
continue;
+ // Skip reserved registers.
+ if (reservedRegs_.test(Reg))
+ continue;
if (isRegAvail(Reg) && Reg < inactiveCounts.size() &&
FreeRegInactiveCount < inactiveCounts[Reg] && !isRecentlyUsed(Reg)) {
FreeReg = Reg;
unsigned RALinScan::getFreePhysReg(LiveInterval *cur) {
SmallVector<unsigned, 256> inactiveCounts;
unsigned MaxInactiveCount = 0;
-
+
const TargetRegisterClass *RC = mri_->getRegClass(cur->reg);
const TargetRegisterClass *RCLeader = RelatedRegClasses.getLeaderValue(RC);
-
+
for (IntervalPtrs::iterator i = inactive_.begin(), e = inactive_.end();
i != e; ++i) {
unsigned reg = i->first->reg;
assert(TargetRegisterInfo::isVirtualRegister(reg) &&
"Can only allocate virtual registers!");
- // If this is not in a related reg class to the register we're allocating,
+ // If this is not in a related reg class to the register we're allocating,
// don't check it.
const TargetRegisterClass *RegRC = mri_->getRegClass(reg);
if (RelatedRegClasses.getLeaderValue(RegRC) == RCLeader) {
// available first.
unsigned Preference = vrm_->getRegAllocPref(cur->reg);
if (Preference) {
- DEBUG(errs() << "(preferred: " << tri_->getName(Preference) << ") ");
- if (isRegAvail(Preference) &&
+ DEBUG(dbgs() << "(preferred: " << tri_->getName(Preference) << ") ");
+ if (isRegAvail(Preference) &&
RC->contains(Preference))
return Preference;
}
projects / oota-llvm.git / blobdiff