//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "regalloc"
-#include "PhysRegTracker.h"
#include "VirtRegMap.h"
+#include "VirtRegRewriter.h"
#include "Spiller.h"
#include "llvm/Function.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/Compiler.h"
+#include "llvm/Support/ErrorHandling.h"
#include <algorithm>
#include <set>
#include <queue>
#include <memory>
#include <cmath>
+
using namespace llvm;
STATISTIC(NumIters , "Number of iterations performed");
cl::desc("Pre-register allocation live interval splitting"),
cl::init(false), cl::Hidden);
+static cl::opt<bool>
+NewSpillFramework("new-spill-framework",
+ cl::desc("New spilling framework"),
+ cl::init(false), cl::Hidden);
+
static RegisterRegAlloc
linearscanRegAlloc("linearscan", "linear scan register allocator",
createLinearScanRegisterAllocator);
SmallVector<LiveInterval*, 64>,
greater_ptr<LiveInterval> > IntervalHeap;
IntervalHeap unhandled_;
- std::auto_ptr<PhysRegTracker> prt_;
+
+ /// regUse_ - Tracks register usage.
+ SmallVector<unsigned, 32> regUse_;
+ SmallVector<unsigned, 32> regUseBackUp_;
+
+ /// vrm_ - Tracks register assignments.
VirtRegMap* vrm_;
+
+ std::auto_ptr<VirtRegRewriter> rewriter_;
+
std::auto_ptr<Spiller> spiller_;
public:
unsigned attemptTrivialCoalescing(LiveInterval &cur, unsigned Reg);
///
- /// register handling helpers
+ /// Register usage / availability tracking helpers.
+ ///
+
+ void initRegUses() {
+ regUse_.resize(tri_->getNumRegs(), 0);
+ regUseBackUp_.resize(tri_->getNumRegs(), 0);
+ }
+
+ void finalizeRegUses() {
+#ifndef NDEBUG
+ // Verify all the registers are "freed".
+ bool Error = false;
+ for (unsigned i = 0, e = tri_->getNumRegs(); i != e; ++i) {
+ if (regUse_[i] != 0) {
+ cerr << tri_->getName(i) << " is still in use!\n";
+ Error = true;
+ }
+ }
+ if (Error)
+ llvm_unreachable(0);
+#endif
+ regUse_.clear();
+ regUseBackUp_.clear();
+ }
+
+ void addRegUse(unsigned physReg) {
+ assert(TargetRegisterInfo::isPhysicalRegister(physReg) &&
+ "should be physical register!");
+ ++regUse_[physReg];
+ for (const unsigned* as = tri_->getAliasSet(physReg); *as; ++as)
+ ++regUse_[*as];
+ }
+
+ void delRegUse(unsigned physReg) {
+ assert(TargetRegisterInfo::isPhysicalRegister(physReg) &&
+ "should be physical register!");
+ assert(regUse_[physReg] != 0);
+ --regUse_[physReg];
+ for (const unsigned* as = tri_->getAliasSet(physReg); *as; ++as) {
+ assert(regUse_[*as] != 0);
+ --regUse_[*as];
+ }
+ }
+
+ bool isRegAvail(unsigned physReg) const {
+ assert(TargetRegisterInfo::isPhysicalRegister(physReg) &&
+ "should be physical register!");
+ return regUse_[physReg] == 0;
+ }
+
+ void backUpRegUses() {
+ regUseBackUp_ = regUse_;
+ }
+
+ void restoreRegUses() {
+ regUse_ = regUseBackUp_;
+ }
+
+ ///
+ /// Register handling helpers.
///
/// getFreePhysReg - return a free physical register for this virtual
/// register interval if we have one, otherwise return 0.
unsigned getFreePhysReg(LiveInterval* cur);
- unsigned getFreePhysReg(const TargetRegisterClass *RC,
+ unsigned getFreePhysReg(LiveInterval* cur,
+ const TargetRegisterClass *RC,
unsigned MaxInactiveCount,
SmallVector<unsigned, 256> &inactiveCounts,
bool SkipDGRegs);
/// different register classes or because the coalescer was overly
/// conservative.
unsigned RALinScan::attemptTrivialCoalescing(LiveInterval &cur, unsigned Reg) {
- if ((cur.preference && cur.preference == Reg) || !cur.containsOneValue())
+ unsigned Preference = vrm_->getRegAllocPref(cur.reg);
+ if ((Preference && Preference == Reg) || !cur.containsOneValue())
return Reg;
VNInfo *vni = cur.begin()->valno;
- if (!vni->def || vni->def == ~1U || vni->def == ~0U)
+ if (!vni->def || vni->isUnused() || !vni->isDefAccurate())
return Reg;
MachineInstr *CopyMI = li_->getInstructionFromIndex(vni->def);
- unsigned SrcReg, DstReg, SrcSubReg, DstSubReg;
+ unsigned SrcReg, DstReg, SrcSubReg, DstSubReg, PhysReg;
if (!CopyMI ||
!tii_->isMoveInstr(*CopyMI, SrcReg, DstReg, SrcSubReg, DstSubReg))
return Reg;
+ PhysReg = SrcReg;
if (TargetRegisterInfo::isVirtualRegister(SrcReg)) {
if (!vrm_->isAssignedReg(SrcReg))
return Reg;
- else
- SrcReg = vrm_->getPhys(SrcReg);
+ PhysReg = vrm_->getPhys(SrcReg);
}
- if (Reg == SrcReg)
+ if (Reg == PhysReg)
return Reg;
const TargetRegisterClass *RC = mri_->getRegClass(cur.reg);
- if (!RC->contains(SrcReg))
+ if (!RC->contains(PhysReg))
return Reg;
// Try to coalesce.
- if (!li_->conflictsWithPhysRegDef(cur, *vrm_, SrcReg)) {
- DOUT << "Coalescing: " << cur << " -> " << tri_->getName(SrcReg)
+ if (!li_->conflictsWithPhysRegDef(cur, *vrm_, PhysReg)) {
+ DOUT << "Coalescing: " << cur << " -> " << tri_->getName(PhysReg)
<< '\n';
vrm_->clearVirt(cur.reg);
- vrm_->assignVirt2Phys(cur.reg, SrcReg);
+ vrm_->assignVirt2Phys(cur.reg, PhysReg);
+
+ // Remove unnecessary kills since a copy does not clobber the register.
+ if (li_->hasInterval(SrcReg)) {
+ LiveInterval &SrcLI = li_->getInterval(SrcReg);
+ for (MachineRegisterInfo::reg_iterator I = mri_->reg_begin(cur.reg),
+ E = mri_->reg_end(); I != E; ++I) {
+ MachineOperand &O = I.getOperand();
+ if (!O.isUse() || !O.isKill())
+ continue;
+ MachineInstr *MI = &*I;
+ if (SrcLI.liveAt(li_->getDefIndex(li_->getInstructionIndex(MI))))
+ O.setIsKill(false);
+ }
+ }
+
++NumCoalesce;
- return SrcReg;
+ return PhysReg;
}
return Reg;
// If this is the first function compiled, compute the related reg classes.
if (RelatedRegClasses.empty())
ComputeRelatedRegClasses();
-
- if (!prt_.get()) prt_.reset(new PhysRegTracker(*tri_));
- vrm_ = &getAnalysis<VirtRegMap>();
- if (!spiller_.get()) spiller_.reset(createSpiller());
+ // Also resize register usage trackers.
+ initRegUses();
+
+ vrm_ = &getAnalysis<VirtRegMap>();
+ if (!rewriter_.get()) rewriter_.reset(createVirtRegRewriter());
+
+ if (NewSpillFramework) {
+ spiller_.reset(createSpiller(mf_, li_, ls_, vrm_));
+ }
+
initIntervalSets();
linearScan();
// Rewrite spill code and update the PhysRegsUsed set.
- spiller_->runOnMachineFunction(*mf_, *vrm_, li_);
+ rewriter_->runOnMachineFunction(*mf_, *vrm_, li_);
assert(unhandled_.empty() && "Unhandled live intervals remain!");
+
+ finalizeRegUses();
+
fixed_.clear();
active_.clear();
inactive_.clear();
NextReloadMap.clear();
DowngradedRegs.clear();
DowngradeMap.clear();
+ spiller_.reset(0);
return true;
}
DEBUG(printIntervals("inactive", inactive_.begin(), inactive_.end()));
}
- // expire any remaining active intervals
+ // Expire any remaining active intervals
while (!active_.empty()) {
IntervalPtr &IP = active_.back();
unsigned reg = IP.first->reg;
assert(TargetRegisterInfo::isVirtualRegister(reg) &&
"Can only allocate virtual registers!");
reg = vrm_->getPhys(reg);
- prt_->delRegUse(reg);
+ delRegUse(reg);
active_.pop_back();
}
- // expire any remaining inactive intervals
+ // Expire any remaining inactive intervals
DEBUG(for (IntervalPtrs::reverse_iterator
i = inactive_.rbegin(); i != inactive_.rend(); ++i)
DOUT << "\tinterval " << *i->first << " expired\n");
// Ignore splited live intervals.
if (!isPhys && vrm_->getPreSplitReg(cur.reg))
continue;
+
for (LiveInterval::Ranges::const_iterator I = cur.begin(), E = cur.end();
I != E; ++I) {
const LiveRange &LR = *I;
if (li_->findLiveInMBBs(LR.start, LR.end, LiveInMBBs)) {
for (unsigned i = 0, e = LiveInMBBs.size(); i != e; ++i)
- if (LiveInMBBs[i] != EntryMBB)
+ if (LiveInMBBs[i] != EntryMBB) {
+ assert(TargetRegisterInfo::isPhysicalRegister(Reg) &&
+ "Adding a virtual register to livein set?");
LiveInMBBs[i]->addLiveIn(Reg);
+ }
LiveInMBBs.clear();
}
}
}
DOUT << *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;
}
/// processActiveIntervals - expire old intervals and move non-overlapping ones
assert(TargetRegisterInfo::isVirtualRegister(reg) &&
"Can only allocate virtual registers!");
reg = vrm_->getPhys(reg);
- prt_->delRegUse(reg);
+ delRegUse(reg);
// Pop off the end of the list.
active_[i] = active_.back();
assert(TargetRegisterInfo::isVirtualRegister(reg) &&
"Can only allocate virtual registers!");
reg = vrm_->getPhys(reg);
- prt_->delRegUse(reg);
+ delRegUse(reg);
// add to inactive.
inactive_.push_back(std::make_pair(Interval, IntervalPos));
assert(TargetRegisterInfo::isVirtualRegister(reg) &&
"Can only allocate virtual registers!");
reg = vrm_->getPhys(reg);
- prt_->addRegUse(reg);
+ addRegUse(reg);
// add to active
active_.push_back(std::make_pair(Interval, IntervalPos));
// bl should get the same spill weight otherwise it will be choosen
// as a spill candidate since spilling bh doesn't make ebx available.
for (unsigned i = 0, e = Supers.size(); i != e; ++i) {
- for (const unsigned *sr = tri_->getSubRegisters(Supers[i]); *sr; ++sr)
- if (!Processed.count(*sr))
- Weights[*sr] += weight;
+ for (const unsigned *sr = tri_->getSubRegisters(Supers[i]); *sr; ++sr)
+ if (!Processed.count(*sr))
+ Weights[*sr] += weight;
}
}
/// addStackInterval - Create a LiveInterval for stack if the specified live
/// interval has been spilled.
static void addStackInterval(LiveInterval *cur, LiveStacks *ls_,
- LiveIntervals *li_, float &Weight,
- VirtRegMap &vrm_) {
+ LiveIntervals *li_,
+ MachineRegisterInfo* mri_, VirtRegMap &vrm_) {
int SS = vrm_.getStackSlot(cur->reg);
if (SS == VirtRegMap::NO_STACK_SLOT)
return;
- LiveInterval &SI = ls_->getOrCreateInterval(SS);
- SI.weight += Weight;
+
+ 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(~0U, 0, ls_->getVNInfoAllocator());
+ VNI = SI.getNextValue(0, 0, false, ls_->getVNInfoAllocator());
LiveInterval &RI = li_->getInterval(cur->reg);
// FIXME: This may be overly conservative.
/// 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) {
+static
+float getConflictWeight(LiveInterval *cur, unsigned Reg, LiveIntervals *li_,
+ MachineRegisterInfo *mri_,
+ const MachineLoopInfo *loopInfo) {
float Conflicts = 0;
for (MachineRegisterInfo::reg_iterator I = mri_->reg_begin(Reg),
E = mri_->reg_end(); I != E; ++I) {
// This is an implicitly defined live interval, just assign any register.
const TargetRegisterClass *RC = mri_->getRegClass(cur->reg);
if (cur->empty()) {
- unsigned physReg = cur->preference;
+ unsigned physReg = vrm_->getRegAllocPref(cur->reg);
if (!physReg)
physReg = *RC->allocation_order_begin(*mf_);
DOUT << tri_->getName(physReg) << '\n';
return;
}
- PhysRegTracker backupPrt = *prt_;
+ backUpRegUses();
std::vector<std::pair<unsigned, float> > SpillWeightsToAdd;
unsigned StartPosition = cur->beginNumber();
// register class, then we should try to assign it the same register.
// This can happen when the move is from a larger register class to a smaller
// one, e.g. X86::mov32to32_. These move instructions are not coalescable.
- if (!cur->preference && cur->hasAtLeastOneValue()) {
+ if (!vrm_->getRegAllocPref(cur->reg) && cur->hasAtLeastOneValue()) {
VNInfo *vni = cur->begin()->valno;
- if (vni->def && vni->def != ~1U && vni->def != ~0U) {
+ if (vni->def && !vni->isUnused() && vni->isDefAccurate()) {
MachineInstr *CopyMI = li_->getInstructionFromIndex(vni->def);
unsigned SrcReg, DstReg, SrcSubReg, DstSubReg;
if (CopyMI &&
if (DstSubReg)
Reg = tri_->getMatchingSuperReg(Reg, DstSubReg, RC);
if (Reg && allocatableRegs_[Reg] && RC->contains(Reg))
- cur->preference = Reg;
+ mri_->setRegAllocationHint(cur->reg, 0, Reg);
}
}
}
}
- // for every interval in inactive we overlap with, mark the
+ // For every interval in inactive we overlap with, mark the
// register as not free and update spill weights.
for (IntervalPtrs::const_iterator i = inactive_.begin(),
e = inactive_.end(); i != e; ++i) {
if (RelatedRegClasses.getLeaderValue(RegRC) == RCLeader &&
cur->overlapsFrom(*i->first, i->second-1)) {
Reg = vrm_->getPhys(Reg);
- prt_->addRegUse(Reg);
+ addRegUse(Reg);
SpillWeightsToAdd.push_back(std::make_pair(Reg, i->first->weight));
}
}
// Okay, the register picked by our speculative getFreePhysReg call turned
// out to be in use. Actually add all of the conflicting fixed registers to
- // prt so we can do an accurate query.
+ // regUse_ so we can do an accurate query.
if (ConflictsWithFixed) {
// For every interval in fixed we overlap with, mark the register as not
// free and update spill weights.
--II;
if (cur->overlapsFrom(*I, II)) {
unsigned reg = I->reg;
- prt_->addRegUse(reg);
+ addRegUse(reg);
SpillWeightsToAdd.push_back(std::make_pair(reg, I->weight));
}
}
}
- // Using the newly updated prt_ object, which includes conflicts in the
+ // Using the newly updated regUse_ object, which includes conflicts in the
// future, see if there are any registers available.
physReg = getFreePhysReg(cur);
}
// Restore the physical register tracker, removing information about the
// future.
- *prt_ = backupPrt;
+ restoreRegUses();
- // if we find a free register, we are done: assign this virtual to
+ // 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) {
DOUT << tri_->getName(physReg) << '\n';
vrm_->assignVirt2Phys(cur->reg, physReg);
- prt_->addRegUse(physReg);
+ addRegUse(physReg);
active_.push_back(std::make_pair(cur, cur->begin()));
handled_.push_back(cur);
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.
- NextReloadLI->preference = physReg;
+ mri_->setRegAllocationHint(NextReloadLI->reg, 0, physReg);
DowngradeRegister(cur, physReg);
}
return;
// Find a register to spill.
float minWeight = HUGE_VALF;
- unsigned minReg = 0; /*cur->preference*/; // Try the pref register first.
+ unsigned minReg = 0;
bool Found = false;
std::vector<std::pair<unsigned,float> > RegsWeights;
li_->getApproximateInstructionCount(*cur) == 0) {
// Spill a physical register around defs and uses.
if (li_->spillPhysRegAroundRegDefsUses(*cur, minReg, *vrm_)) {
+ // spillPhysRegAroundRegDefsUses may have invalidated iterator stored
+ // in fixed_. Reset them.
+ for (unsigned i = 0, e = fixed_.size(); i != e; ++i) {
+ IntervalPtr &IP = fixed_[i];
+ LiveInterval *I = IP.first;
+ if (I->reg == minReg || tri_->isSubRegister(minReg, I->reg))
+ IP.second = I->advanceTo(I->begin(), StartPosition);
+ }
+
DowngradedRegs.clear();
assignRegOrStackSlotAtInterval(cur);
} else {
- cerr << "Ran out of registers during register allocation!\n";
- exit(1);
+ llvm_report_error("Ran out of registers during register allocation!");
}
return;
}
// linearscan.
if (cur->weight != HUGE_VALF && cur->weight <= minWeight) {
DOUT << "\t\t\tspilling(c): " << *cur << '\n';
- float SSWeight;
SmallVector<LiveInterval*, 8> spillIs;
- std::vector<LiveInterval*> added =
- li_->addIntervalsForSpills(*cur, spillIs, loopInfo, *vrm_, SSWeight);
+ std::vector<LiveInterval*> added;
+
+ if (!NewSpillFramework) {
+ added = li_->addIntervalsForSpills(*cur, spillIs, loopInfo, *vrm_);
+ } else {
+ added = spiller_->spill(cur);
+ }
+
std::sort(added.begin(), added.end(), LISorter());
- addStackInterval(cur, ls_, li_, SSWeight, *vrm_);
+ 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
- unsigned earliestStart = cur->beginNumber();
+
+ LiveInterval *earliestStartInterval = cur;
// 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
LiveInterval *sli = spillIs.back();
spillIs.pop_back();
DOUT << "\t\t\tspilling(a): " << *sli << '\n';
- earliestStart = std::min(earliestStart, sli->beginNumber());
- float SSWeight;
- std::vector<LiveInterval*> newIs =
- li_->addIntervalsForSpills(*sli, spillIs, loopInfo, *vrm_, SSWeight);
- addStackInterval(sli, ls_, li_, SSWeight, *vrm_);
+ earliestStartInterval =
+ (earliestStartInterval->beginNumber() < sli->beginNumber()) ?
+ earliestStartInterval : sli;
+
+ std::vector<LiveInterval*> newIs;
+ if (!NewSpillFramework) {
+ newIs = li_->addIntervalsForSpills(*sli, spillIs, loopInfo, *vrm_);
+ } else {
+ newIs = spiller_->spill(sli);
+ }
+ addStackInterval(sli, ls_, li_, mri_, *vrm_);
std::copy(newIs.begin(), newIs.end(), std::back_inserter(added));
spilled.insert(sli->reg);
}
+ unsigned earliestStart = earliestStartInterval->beginNumber();
+
DOUT << "\t\trolling back to: " << earliestStart << '\n';
// Scan handled in reverse order up to the earliest start of a
handled_.pop_back();
// When undoing a live interval allocation we must know if it is active or
- // inactive to properly update the PhysRegTracker and the VirtRegMap.
+ // inactive to properly update regUse_ and the VirtRegMap.
IntervalPtrs::iterator it;
if ((it = FindIntervalInVector(active_, i)) != active_.end()) {
active_.erase(it);
assert(!TargetRegisterInfo::isPhysicalRegister(i->reg));
if (!spilled.count(i->reg))
unhandled_.push(i);
- prt_->delRegUse(vrm_->getPhys(i->reg));
+ delRegUse(vrm_->getPhys(i->reg));
vrm_->clearVirt(i->reg);
} else if ((it = FindIntervalInVector(inactive_, i)) != inactive_.end()) {
inactive_.erase(it);
// It interval has a preference, it must be defined by a copy. Clear the
// preference now since the source interval allocation may have been
// undone as well.
- i->preference = 0;
+ mri_->setRegAllocationHint(i->reg, 0, 0);
else {
UpgradeRegister(ii->second);
}
DOUT << "\t\t\tundo changes for: " << *HI << '\n';
active_.push_back(std::make_pair(HI, HI->begin()));
assert(!TargetRegisterInfo::isPhysicalRegister(HI->reg));
- prt_->addRegUse(vrm_->getPhys(HI->reg));
+ addRegUse(vrm_->getPhys(HI->reg));
}
}
}
}
-unsigned RALinScan::getFreePhysReg(const TargetRegisterClass *RC,
+unsigned RALinScan::getFreePhysReg(LiveInterval* cur,
+ const TargetRegisterClass *RC,
unsigned MaxInactiveCount,
SmallVector<unsigned, 256> &inactiveCounts,
bool SkipDGRegs) {
unsigned FreeReg = 0;
unsigned FreeRegInactiveCount = 0;
- TargetRegisterClass::iterator I = RC->allocation_order_begin(*mf_);
- TargetRegisterClass::iterator E = RC->allocation_order_end(*mf_);
+ 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))
+ physReg = vrm_->getPhys(physReg);
+
+ TargetRegisterClass::iterator I, E;
+ tie(I, E) = tri_->getAllocationOrder(RC, Hint.first, physReg, *mf_);
assert(I != E && "No allocatable register in this register class!");
// Scan for the first available register.
// Ignore "downgraded" registers.
if (SkipDGRegs && DowngradedRegs.count(Reg))
continue;
- if (prt_->isRegAvail(Reg)) {
+ if (isRegAvail(Reg)) {
FreeReg = Reg;
if (FreeReg < inactiveCounts.size())
FreeRegInactiveCount = inactiveCounts[FreeReg];
// return this register.
if (FreeReg == 0 || FreeRegInactiveCount == MaxInactiveCount)
return FreeReg;
-
+
// Continue scanning the registers, looking for the one with the highest
// inactive count. Alkis found that this reduced register pressure very
// slightly on X86 (in rev 1.94 of this file), though this should probably be
// Ignore "downgraded" registers.
if (SkipDGRegs && DowngradedRegs.count(Reg))
continue;
- if (prt_->isRegAvail(Reg) && Reg < inactiveCounts.size() &&
+ if (isRegAvail(Reg) && Reg < inactiveCounts.size() &&
FreeRegInactiveCount < inactiveCounts[Reg]) {
FreeReg = Reg;
FreeRegInactiveCount = inactiveCounts[Reg];
// If copy coalescer has assigned a "preferred" register, check if it's
// available first.
- if (cur->preference) {
- DOUT << "(preferred: " << tri_->getName(cur->preference) << ") ";
- if (prt_->isRegAvail(cur->preference) &&
- RC->contains(cur->preference))
- return cur->preference;
+ unsigned Preference = vrm_->getRegAllocPref(cur->reg);
+ if (Preference) {
+ DOUT << "(preferred: " << tri_->getName(Preference) << ") ";
+ if (isRegAvail(Preference) &&
+ RC->contains(Preference))
+ return Preference;
}
if (!DowngradedRegs.empty()) {
- unsigned FreeReg = getFreePhysReg(RC, MaxInactiveCount, inactiveCounts,
+ unsigned FreeReg = getFreePhysReg(cur, RC, MaxInactiveCount, inactiveCounts,
true);
if (FreeReg)
return FreeReg;
}
- return getFreePhysReg(RC, MaxInactiveCount, inactiveCounts, false);
+ return getFreePhysReg(cur, RC, MaxInactiveCount, inactiveCounts, false);
}
FunctionPass* llvm::createLinearScanRegisterAllocator() {