diff options
Diffstat (limited to 'lib/CodeGen/VirtRegMap.cpp')
-rw-r--r-- | lib/CodeGen/VirtRegMap.cpp | 168 |
1 files changed, 12 insertions, 156 deletions
diff --git a/lib/CodeGen/VirtRegMap.cpp b/lib/CodeGen/VirtRegMap.cpp index 8a1cdc0..3bab93b 100644 --- a/lib/CodeGen/VirtRegMap.cpp +++ b/lib/CodeGen/VirtRegMap.cpp @@ -16,10 +16,9 @@ // //===----------------------------------------------------------------------===// -#define DEBUG_TYPE "virtregmap" +#define DEBUG_TYPE "regalloc" #include "VirtRegMap.h" #include "llvm/Function.h" -#include "llvm/CodeGen/LiveIntervalAnalysis.h" #include "llvm/CodeGen/MachineFrameInfo.h" #include "llvm/CodeGen/MachineFunction.h" #include "llvm/CodeGen/MachineInstrBuilder.h" @@ -32,12 +31,8 @@ #include "llvm/Support/Compiler.h" #include "llvm/Support/Debug.h" #include "llvm/Support/raw_ostream.h" -#include "llvm/ADT/BitVector.h" -#include "llvm/ADT/DenseMap.h" -#include "llvm/ADT/DepthFirstIterator.h" #include "llvm/ADT/Statistic.h" #include "llvm/ADT/STLExtras.h" -#include "llvm/ADT/SmallSet.h" #include <algorithm> using namespace llvm; @@ -58,34 +53,11 @@ bool VirtRegMap::runOnMachineFunction(MachineFunction &mf) { TRI = mf.getTarget().getRegisterInfo(); MF = &mf; - ReMatId = MAX_STACK_SLOT+1; - LowSpillSlot = HighSpillSlot = NO_STACK_SLOT; - Virt2PhysMap.clear(); Virt2StackSlotMap.clear(); - Virt2ReMatIdMap.clear(); Virt2SplitMap.clear(); - Virt2SplitKillMap.clear(); - ReMatMap.clear(); - ImplicitDefed.clear(); - SpillSlotToUsesMap.clear(); - MI2VirtMap.clear(); - SpillPt2VirtMap.clear(); - RestorePt2VirtMap.clear(); - EmergencySpillMap.clear(); - EmergencySpillSlots.clear(); - - SpillSlotToUsesMap.resize(8); - ImplicitDefed.resize(MF->getRegInfo().getNumVirtRegs()); - - allocatableRCRegs.clear(); - for (TargetRegisterInfo::regclass_iterator I = TRI->regclass_begin(), - E = TRI->regclass_end(); I != E; ++I) - allocatableRCRegs.insert(std::make_pair(*I, - TRI->getAllocatableSet(mf, *I))); grow(); - return false; } @@ -93,24 +65,12 @@ void VirtRegMap::grow() { unsigned NumRegs = MF->getRegInfo().getNumVirtRegs(); Virt2PhysMap.resize(NumRegs); Virt2StackSlotMap.resize(NumRegs); - Virt2ReMatIdMap.resize(NumRegs); Virt2SplitMap.resize(NumRegs); - Virt2SplitKillMap.resize(NumRegs); - ReMatMap.resize(NumRegs); - ImplicitDefed.resize(NumRegs); } unsigned VirtRegMap::createSpillSlot(const TargetRegisterClass *RC) { int SS = MF->getFrameInfo()->CreateSpillStackObject(RC->getSize(), RC->getAlignment()); - if (LowSpillSlot == NO_STACK_SLOT) - LowSpillSlot = SS; - if (HighSpillSlot == NO_STACK_SLOT || SS > HighSpillSlot) - HighSpillSlot = SS; - assert(SS >= LowSpillSlot && "Unexpected low spill slot"); - unsigned Idx = SS-LowSpillSlot; - while (Idx >= SpillSlotToUsesMap.size()) - SpillSlotToUsesMap.resize(SpillSlotToUsesMap.size()*2); ++NumSpillSlots; return SS; } @@ -144,118 +104,6 @@ void VirtRegMap::assignVirt2StackSlot(unsigned virtReg, int SS) { Virt2StackSlotMap[virtReg] = SS; } -int VirtRegMap::assignVirtReMatId(unsigned virtReg) { - assert(TargetRegisterInfo::isVirtualRegister(virtReg)); - assert(Virt2ReMatIdMap[virtReg] == NO_STACK_SLOT && - "attempt to assign re-mat id to already spilled register"); - Virt2ReMatIdMap[virtReg] = ReMatId; - return ReMatId++; -} - -void VirtRegMap::assignVirtReMatId(unsigned virtReg, int id) { - assert(TargetRegisterInfo::isVirtualRegister(virtReg)); - assert(Virt2ReMatIdMap[virtReg] == NO_STACK_SLOT && - "attempt to assign re-mat id to already spilled register"); - Virt2ReMatIdMap[virtReg] = id; -} - -int VirtRegMap::getEmergencySpillSlot(const TargetRegisterClass *RC) { - std::map<const TargetRegisterClass*, int>::iterator I = - EmergencySpillSlots.find(RC); - if (I != EmergencySpillSlots.end()) - return I->second; - return EmergencySpillSlots[RC] = createSpillSlot(RC); -} - -void VirtRegMap::addSpillSlotUse(int FI, MachineInstr *MI) { - if (!MF->getFrameInfo()->isFixedObjectIndex(FI)) { - // If FI < LowSpillSlot, this stack reference was produced by - // instruction selection and is not a spill - if (FI >= LowSpillSlot) { - assert(FI >= 0 && "Spill slot index should not be negative!"); - assert((unsigned)FI-LowSpillSlot < SpillSlotToUsesMap.size() - && "Invalid spill slot"); - SpillSlotToUsesMap[FI-LowSpillSlot].insert(MI); - } - } -} - -void VirtRegMap::virtFolded(unsigned VirtReg, MachineInstr *OldMI, - MachineInstr *NewMI, ModRef MRInfo) { - // Move previous memory references folded to new instruction. - MI2VirtMapTy::iterator IP = MI2VirtMap.lower_bound(NewMI); - for (MI2VirtMapTy::iterator I = MI2VirtMap.lower_bound(OldMI), - E = MI2VirtMap.end(); I != E && I->first == OldMI; ) { - MI2VirtMap.insert(IP, std::make_pair(NewMI, I->second)); - MI2VirtMap.erase(I++); - } - - // add new memory reference - MI2VirtMap.insert(IP, std::make_pair(NewMI, std::make_pair(VirtReg, MRInfo))); -} - -void VirtRegMap::virtFolded(unsigned VirtReg, MachineInstr *MI, ModRef MRInfo) { - MI2VirtMapTy::iterator IP = MI2VirtMap.lower_bound(MI); - MI2VirtMap.insert(IP, std::make_pair(MI, std::make_pair(VirtReg, MRInfo))); -} - -void VirtRegMap::RemoveMachineInstrFromMaps(MachineInstr *MI) { - for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { - MachineOperand &MO = MI->getOperand(i); - if (!MO.isFI()) - continue; - int FI = MO.getIndex(); - if (MF->getFrameInfo()->isFixedObjectIndex(FI)) - continue; - // This stack reference was produced by instruction selection and - // is not a spill - if (FI < LowSpillSlot) - continue; - assert((unsigned)FI-LowSpillSlot < SpillSlotToUsesMap.size() - && "Invalid spill slot"); - SpillSlotToUsesMap[FI-LowSpillSlot].erase(MI); - } - MI2VirtMap.erase(MI); - SpillPt2VirtMap.erase(MI); - RestorePt2VirtMap.erase(MI); - EmergencySpillMap.erase(MI); -} - -/// FindUnusedRegisters - Gather a list of allocatable registers that -/// have not been allocated to any virtual register. -bool VirtRegMap::FindUnusedRegisters(LiveIntervals* LIs) { - unsigned NumRegs = TRI->getNumRegs(); - UnusedRegs.reset(); - UnusedRegs.resize(NumRegs); - - BitVector Used(NumRegs); - for (unsigned i = 0, e = MRI->getNumVirtRegs(); i != e; ++i) { - unsigned Reg = TargetRegisterInfo::index2VirtReg(i); - if (Virt2PhysMap[Reg] != (unsigned)VirtRegMap::NO_PHYS_REG) - Used.set(Virt2PhysMap[Reg]); - } - - BitVector Allocatable = TRI->getAllocatableSet(*MF); - bool AnyUnused = false; - for (unsigned Reg = 1; Reg < NumRegs; ++Reg) { - if (Allocatable[Reg] && !Used[Reg] && !LIs->hasInterval(Reg)) { - bool ReallyUnused = true; - for (const unsigned *AS = TRI->getAliasSet(Reg); *AS; ++AS) { - if (Used[*AS] || LIs->hasInterval(*AS)) { - ReallyUnused = false; - break; - } - } - if (ReallyUnused) { - AnyUnused = true; - UnusedRegs.set(Reg); - } - } - } - - return AnyUnused; -} - void VirtRegMap::rewrite(SlotIndexes *Indexes) { DEBUG(dbgs() << "********** REWRITE VIRTUAL REGISTERS **********\n" << "********** Function: " @@ -264,23 +112,32 @@ void VirtRegMap::rewrite(SlotIndexes *Indexes) { SmallVector<unsigned, 8> SuperDeads; SmallVector<unsigned, 8> SuperDefs; SmallVector<unsigned, 8> SuperKills; +#ifndef NDEBUG + BitVector Reserved = TRI->getReservedRegs(*MF); +#endif for (MachineFunction::iterator MBBI = MF->begin(), MBBE = MF->end(); MBBI != MBBE; ++MBBI) { DEBUG(MBBI->print(dbgs(), Indexes)); - for (MachineBasicBlock::iterator MII = MBBI->begin(), MIE = MBBI->end(); - MII != MIE;) { + for (MachineBasicBlock::instr_iterator + MII = MBBI->instr_begin(), MIE = MBBI->instr_end(); MII != MIE;) { MachineInstr *MI = MII; ++MII; for (MachineInstr::mop_iterator MOI = MI->operands_begin(), MOE = MI->operands_end(); MOI != MOE; ++MOI) { MachineOperand &MO = *MOI; + + // Make sure MRI knows about registers clobbered by regmasks. + if (MO.isRegMask()) + MRI->addPhysRegsUsedFromRegMask(MO.getRegMask()); + if (!MO.isReg() || !TargetRegisterInfo::isVirtualRegister(MO.getReg())) continue; unsigned VirtReg = MO.getReg(); unsigned PhysReg = getPhys(VirtReg); assert(PhysReg != NO_PHYS_REG && "Instruction uses unmapped VirtReg"); + assert(!Reserved.test(PhysReg) && "Reserved register assignment"); // Preserve semantics of sub-register operands. if (MO.getSubReg()) { @@ -332,7 +189,6 @@ void VirtRegMap::rewrite(SlotIndexes *Indexes) { ++NumIdCopies; if (MI->getNumOperands() == 2) { DEBUG(dbgs() << "Deleting identity copy.\n"); - RemoveMachineInstrFromMaps(MI); if (Indexes) Indexes->removeMachineInstrFromMaps(MI); // It's safe to erase MI because MII has already been incremented. |