X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=blobdiff_plain;f=lib%2FCodeGen%2FAggressiveAntiDepBreaker.cpp;h=b0c3906b02e1dd949b416ccc92a7959de89c56e1;hp=c23351b6e5afbfc245f85426e3c3d9789d5982d1;hb=b78fd035a230c05e5cb6a7e0afdd3cbf7b3e9239;hpb=fa796dd720f1b34596a043f17f098fac18ecc028 diff --git a/lib/CodeGen/AggressiveAntiDepBreaker.cpp b/lib/CodeGen/AggressiveAntiDepBreaker.cpp index c23351b6e5a..b0c3906b02e 100644 --- a/lib/CodeGen/AggressiveAntiDepBreaker.cpp +++ b/lib/CodeGen/AggressiveAntiDepBreaker.cpp @@ -14,22 +14,22 @@ // //===----------------------------------------------------------------------===// -#define DEBUG_TYPE "post-RA-sched" #include "AggressiveAntiDepBreaker.h" -#include "RegisterClassInfo.h" #include "llvm/CodeGen/MachineBasicBlock.h" #include "llvm/CodeGen/MachineFrameInfo.h" #include "llvm/CodeGen/MachineInstr.h" -#include "llvm/Target/TargetInstrInfo.h" -#include "llvm/Target/TargetMachine.h" -#include "llvm/Target/TargetInstrInfo.h" -#include "llvm/Target/TargetRegisterInfo.h" +#include "llvm/CodeGen/RegisterClassInfo.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/raw_ostream.h" +#include "llvm/Target/TargetInstrInfo.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/TargetRegisterInfo.h" using namespace llvm; +#define DEBUG_TYPE "post-RA-sched" + // If DebugDiv > 0 then only break antidep with (ID % DebugDiv) == DebugMod static cl::opt DebugDiv("agg-antidep-debugdiv", @@ -111,18 +111,13 @@ bool AggressiveAntiDepState::IsLive(unsigned Reg) return((KillIndices[Reg] != ~0u) && (DefIndices[Reg] == ~0u)); } - - -AggressiveAntiDepBreaker:: -AggressiveAntiDepBreaker(MachineFunction& MFi, - const RegisterClassInfo &RCI, - TargetSubtarget::RegClassVector& CriticalPathRCs) : - AntiDepBreaker(), MF(MFi), - MRI(MF.getRegInfo()), - TII(MF.getTarget().getInstrInfo()), - TRI(MF.getTarget().getRegisterInfo()), - RegClassInfo(RCI), - State(NULL) { +AggressiveAntiDepBreaker::AggressiveAntiDepBreaker( + MachineFunction &MFi, const RegisterClassInfo &RCI, + TargetSubtargetInfo::RegClassVector &CriticalPathRCs) + : AntiDepBreaker(), MF(MFi), MRI(MF.getRegInfo()), + TII(MF.getSubtarget().getInstrInfo()), + TRI(MF.getSubtarget().getRegisterInfo()), RegClassInfo(RCI), + State(nullptr) { /* Collect a bitset of all registers that are only broken if they are on the critical path. */ for (unsigned i = 0, e = CriticalPathRCs.size(); i < e; ++i) { @@ -145,36 +140,20 @@ AggressiveAntiDepBreaker::~AggressiveAntiDepBreaker() { } void AggressiveAntiDepBreaker::StartBlock(MachineBasicBlock *BB) { - assert(State == NULL); + assert(!State); State = new AggressiveAntiDepState(TRI->getNumRegs(), BB); - bool IsReturnBlock = (!BB->empty() && BB->back().getDesc().isReturn()); + bool IsReturnBlock = (!BB->empty() && BB->back().isReturn()); std::vector &KillIndices = State->GetKillIndices(); std::vector &DefIndices = State->GetDefIndices(); - // Determine the live-out physregs for this block. - if (IsReturnBlock) { - // In a return block, examine the function live-out regs. - for (MachineRegisterInfo::liveout_iterator I = MRI.liveout_begin(), - E = MRI.liveout_end(); I != E; ++I) { - for (const unsigned *Alias = TRI->getOverlaps(*I); - unsigned Reg = *Alias; ++Alias) { - State->UnionGroups(Reg, 0); - KillIndices[Reg] = BB->size(); - DefIndices[Reg] = ~0u; - } - } - } - - // In a non-return block, examine the live-in regs of all successors. - // Note a return block can have successors if the return instruction is - // predicated. + // Examine the live-in regs of all successors. for (MachineBasicBlock::succ_iterator SI = BB->succ_begin(), SE = BB->succ_end(); SI != SE; ++SI) for (MachineBasicBlock::livein_iterator I = (*SI)->livein_begin(), E = (*SI)->livein_end(); I != E; ++I) { - for (const unsigned *Alias = TRI->getOverlaps(*I); - unsigned Reg = *Alias; ++Alias) { + for (MCRegAliasIterator AI(*I, TRI, true); AI.isValid(); ++AI) { + unsigned Reg = *AI; State->UnionGroups(Reg, 0); KillIndices[Reg] = BB->size(); DefIndices[Reg] = ~0u; @@ -186,11 +165,11 @@ void AggressiveAntiDepBreaker::StartBlock(MachineBasicBlock *BB) { // callee-saved register that is not saved in the prolog. const MachineFrameInfo *MFI = MF.getFrameInfo(); BitVector Pristine = MFI->getPristineRegs(BB); - for (const unsigned *I = TRI->getCalleeSavedRegs(); *I; ++I) { + for (const MCPhysReg *I = TRI->getCalleeSavedRegs(&MF); *I; ++I) { unsigned Reg = *I; if (!IsReturnBlock && !Pristine.test(Reg)) continue; - for (const unsigned *Alias = TRI->getOverlaps(Reg); - unsigned AliasReg = *Alias; ++Alias) { + for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) { + unsigned AliasReg = *AI; State->UnionGroups(AliasReg, 0); KillIndices[AliasReg] = BB->size(); DefIndices[AliasReg] = ~0u; @@ -200,7 +179,7 @@ void AggressiveAntiDepBreaker::StartBlock(MachineBasicBlock *BB) { void AggressiveAntiDepBreaker::FinishBlock() { delete State; - State = NULL; + State = nullptr; } void AggressiveAntiDepBreaker::Observe(MachineInstr *MI, unsigned Count, @@ -247,13 +226,13 @@ bool AggressiveAntiDepBreaker::IsImplicitDefUse(MachineInstr *MI, if (Reg == 0) return false; - MachineOperand *Op = NULL; + MachineOperand *Op = nullptr; if (MO.isDef()) Op = MI->findRegisterUseOperand(Reg, true); else Op = MI->findRegisterDefOperand(Reg); - return((Op != NULL) && Op->isImplicit()); + return(Op && Op->isImplicit()); } void AggressiveAntiDepBreaker::GetPassthruRegs(MachineInstr *MI, @@ -264,11 +243,9 @@ void AggressiveAntiDepBreaker::GetPassthruRegs(MachineInstr *MI, if ((MO.isDef() && MI->isRegTiedToUseOperand(i)) || IsImplicitDefUse(MI, MO)) { const unsigned Reg = MO.getReg(); - PassthruRegs.insert(Reg); - for (const unsigned *Subreg = TRI->getSubRegisters(Reg); - *Subreg; ++Subreg) { - PassthruRegs.insert(*Subreg); - } + for (MCSubRegIterator SubRegs(Reg, TRI, /*IncludeSelf=*/true); + SubRegs.isValid(); ++SubRegs) + PassthruRegs.insert(*SubRegs); } } } @@ -292,10 +269,10 @@ static void AntiDepEdges(const SUnit *SU, std::vector& Edges) { /// CriticalPathStep - Return the next SUnit after SU on the bottom-up /// critical path. static const SUnit *CriticalPathStep(const SUnit *SU) { - const SDep *Next = 0; + const SDep *Next = nullptr; unsigned NextDepth = 0; // Find the predecessor edge with the greatest depth. - if (SU != 0) { + if (SU) { for (SUnit::const_pred_iterator P = SU->Preds.begin(), PE = SU->Preds.end(); P != PE; ++P) { const SUnit *PredSU = P->getSUnit(); @@ -311,7 +288,7 @@ static const SUnit *CriticalPathStep(const SUnit *SU) { } } - return (Next) ? Next->getSUnit() : 0; + return (Next) ? Next->getSUnit() : nullptr; } void AggressiveAntiDepBreaker::HandleLastUse(unsigned Reg, unsigned KillIdx, @@ -328,27 +305,26 @@ void AggressiveAntiDepBreaker::HandleLastUse(unsigned Reg, unsigned KillIdx, DefIndices[Reg] = ~0u; RegRefs.erase(Reg); State->LeaveGroup(Reg); - DEBUG(if (header != NULL) { - dbgs() << header << TRI->getName(Reg); header = NULL; }); + DEBUG(if (header) { + dbgs() << header << TRI->getName(Reg); header = nullptr; }); DEBUG(dbgs() << "->g" << State->GetGroup(Reg) << tag); } // Repeat for subregisters. - for (const unsigned *Subreg = TRI->getSubRegisters(Reg); - *Subreg; ++Subreg) { - unsigned SubregReg = *Subreg; + for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs) { + unsigned SubregReg = *SubRegs; if (!State->IsLive(SubregReg)) { KillIndices[SubregReg] = KillIdx; DefIndices[SubregReg] = ~0u; RegRefs.erase(SubregReg); State->LeaveGroup(SubregReg); - DEBUG(if (header != NULL) { - dbgs() << header << TRI->getName(Reg); header = NULL; }); + DEBUG(if (header) { + dbgs() << header << TRI->getName(Reg); header = nullptr; }); DEBUG(dbgs() << " " << TRI->getName(SubregReg) << "->g" << State->GetGroup(SubregReg) << tag); } } - DEBUG(if ((header == NULL) && (footer != NULL)) dbgs() << footer); + DEBUG(if (!header && footer) dbgs() << footer); } void AggressiveAntiDepBreaker::PrescanInstruction(MachineInstr *MI, @@ -384,7 +360,7 @@ void AggressiveAntiDepBreaker::PrescanInstruction(MachineInstr *MI, // If MI's defs have a special allocation requirement, don't allow // any def registers to be changed. Also assume all registers // defined in a call must not be changed (ABI). - if (MI->getDesc().isCall() || MI->getDesc().hasExtraDefRegAllocReq() || + if (MI->isCall() || MI->hasExtraDefRegAllocReq() || TII->isPredicated(MI)) { DEBUG(if (State->GetGroup(Reg) != 0) dbgs() << "->g0(alloc-req)"); State->UnionGroups(Reg, 0); @@ -392,8 +368,8 @@ void AggressiveAntiDepBreaker::PrescanInstruction(MachineInstr *MI, // Any aliased that are live at this point are completely or // partially defined here, so group those aliases with Reg. - for (const unsigned *Alias = TRI->getAliasSet(Reg); *Alias; ++Alias) { - unsigned AliasReg = *Alias; + for (MCRegAliasIterator AI(Reg, TRI, false); AI.isValid(); ++AI) { + unsigned AliasReg = *AI; if (State->IsLive(AliasReg)) { State->UnionGroups(Reg, AliasReg); DEBUG(dbgs() << "->g" << State->GetGroup(Reg) << "(via " << @@ -402,9 +378,9 @@ void AggressiveAntiDepBreaker::PrescanInstruction(MachineInstr *MI, } // Note register reference... - const TargetRegisterClass *RC = NULL; + const TargetRegisterClass *RC = nullptr; if (i < MI->getDesc().getNumOperands()) - RC = MI->getDesc().OpInfo[i].getRegClass(TRI); + RC = TII->getRegClass(MI->getDesc(), i, TRI, MF); AggressiveAntiDepState::RegisterReference RR = { &MO, RC }; RegRefs.insert(std::make_pair(Reg, RR)); } @@ -423,9 +399,18 @@ void AggressiveAntiDepBreaker::PrescanInstruction(MachineInstr *MI, continue; // Update def for Reg and aliases. - for (const unsigned *Alias = TRI->getOverlaps(Reg); - unsigned AliasReg = *Alias; ++Alias) - DefIndices[AliasReg] = Count; + for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) { + // We need to be careful here not to define already-live super registers. + // If the super register is already live, then this definition is not + // a definition of the whole super register (just a partial insertion + // into it). Earlier subregister definitions (which we've not yet visited + // because we're iterating bottom-up) need to be linked to the same group + // as this definition. + if (TRI->isSuperRegister(Reg, *AI) && State->IsLive(*AI)) + continue; + + DefIndices[*AI] = Count; + } } } @@ -451,8 +436,8 @@ void AggressiveAntiDepBreaker::ScanInstruction(MachineInstr *MI, // instruction which may not be executed. The second R6 def may or may not // re-define R6 so it's not safe to change it since the last R6 use cannot be // changed. - bool Special = MI->getDesc().isCall() || - MI->getDesc().hasExtraSrcRegAllocReq() || + bool Special = MI->isCall() || + MI->hasExtraSrcRegAllocReq() || TII->isPredicated(MI); // Scan the register uses for this instruction and update @@ -477,9 +462,9 @@ void AggressiveAntiDepBreaker::ScanInstruction(MachineInstr *MI, } // Note register reference... - const TargetRegisterClass *RC = NULL; + const TargetRegisterClass *RC = nullptr; if (i < MI->getDesc().getNumOperands()) - RC = MI->getDesc().OpInfo[i].getRegClass(TRI); + RC = TII->getRegClass(MI->getDesc(), i, TRI, MF); AggressiveAntiDepState::RegisterReference RR = { &MO, RC }; RegRefs.insert(std::make_pair(Reg, RR)); } @@ -527,7 +512,7 @@ BitVector AggressiveAntiDepBreaker::GetRenameRegisters(unsigned Reg) { AggressiveAntiDepState::RegisterReference>::iterator Q = Range.first, QE = Range.second; Q != QE; ++Q) { const TargetRegisterClass *RC = Q->second.RC; - if (RC == NULL) continue; + if (!RC) continue; BitVector RCBV = TRI->getAllocatableSet(MF, RC); if (first) { @@ -592,7 +577,9 @@ bool AggressiveAntiDepBreaker::FindSuitableFreeRegisters( unsigned Reg = Regs[i]; if (Reg == SuperReg) continue; bool IsSub = TRI->isSubRegister(SuperReg, Reg); - assert(IsSub && "Expecting group subregister"); + // FIXME: remove this once PR18663 has been properly fixed. For now, + // return a conservative answer: + // assert(IsSub && "Expecting group subregister"); if (!IsSub) return false; } @@ -620,7 +607,7 @@ bool AggressiveAntiDepBreaker::FindSuitableFreeRegisters( const TargetRegisterClass *SuperRC = TRI->getMinimalPhysRegClass(SuperReg, MVT::Other); - ArrayRef Order = RegClassInfo.getOrder(SuperRC); + ArrayRef Order = RegClassInfo.getOrder(SuperRC); if (Order.empty()) { DEBUG(dbgs() << "\tEmpty Super Regclass!!\n"); return false; @@ -639,7 +626,7 @@ bool AggressiveAntiDepBreaker::FindSuitableFreeRegisters( --R; const unsigned NewSuperReg = Order[R]; // Don't consider non-allocatable registers - if (!RegClassInfo.isAllocatable(NewSuperReg)) continue; + if (!MRI.isAllocatable(NewSuperReg)) continue; // Don't replace a register with itself. if (NewSuperReg == SuperReg) continue; @@ -678,9 +665,8 @@ bool AggressiveAntiDepBreaker::FindSuitableFreeRegisters( goto next_super_reg; } else { bool found = false; - for (const unsigned *Alias = TRI->getAliasSet(NewReg); - *Alias; ++Alias) { - unsigned AliasReg = *Alias; + for (MCRegAliasIterator AI(NewReg, TRI, false); AI.isValid(); ++AI) { + unsigned AliasReg = *AI; if (State->IsLive(AliasReg) || (KillIndices[Reg] > DefIndices[AliasReg])) { DEBUG(dbgs() << "(alias " << TRI->getName(AliasReg) << " live)"); @@ -746,8 +732,8 @@ unsigned AggressiveAntiDepBreaker::BreakAntiDependencies( // Track progress along the critical path through the SUnit graph as // we walk the instructions. This is needed for regclasses that only // break critical-path anti-dependencies. - const SUnit *CriticalPathSU = 0; - MachineInstr *CriticalPathMI = 0; + const SUnit *CriticalPathSU = nullptr; + MachineInstr *CriticalPathMI = nullptr; if (CriticalPathSet.any()) { for (unsigned i = 0, e = SUnits.size(); i != e; ++i) { const SUnit *SU = &SUnits[i]; @@ -780,6 +766,9 @@ unsigned AggressiveAntiDepBreaker::BreakAntiDependencies( I != E; --Count) { MachineInstr *MI = --I; + if (MI->isDebugValue()) + continue; + DEBUG(dbgs() << "Anti: "); DEBUG(MI->dump()); @@ -797,11 +786,11 @@ unsigned AggressiveAntiDepBreaker::BreakAntiDependencies( // If MI is not on the critical path, then we don't rename // registers in the CriticalPathSet. - BitVector *ExcludeRegs = NULL; + BitVector *ExcludeRegs = nullptr; if (MI == CriticalPathMI) { CriticalPathSU = CriticalPathStep(CriticalPathSU); - CriticalPathMI = (CriticalPathSU) ? CriticalPathSU->getInstr() : 0; - } else { + CriticalPathMI = (CriticalPathSU) ? CriticalPathSU->getInstr() : nullptr; + } else if (CriticalPathSet.any()) { ExcludeRegs = &CriticalPathSet; } @@ -820,11 +809,11 @@ unsigned AggressiveAntiDepBreaker::BreakAntiDependencies( DEBUG(dbgs() << "\tAntidep reg: " << TRI->getName(AntiDepReg)); assert(AntiDepReg != 0 && "Anti-dependence on reg0?"); - if (!RegClassInfo.isAllocatable(AntiDepReg)) { + if (!MRI.isAllocatable(AntiDepReg)) { // Don't break anti-dependencies on non-allocatable registers. DEBUG(dbgs() << " (non-allocatable)\n"); continue; - } else if ((ExcludeRegs != NULL) && ExcludeRegs->test(AntiDepReg)) { + } else if (ExcludeRegs && ExcludeRegs->test(AntiDepReg)) { // Don't break anti-dependencies for critical path registers // if not on the critical path DEBUG(dbgs() << " (not critical-path)\n"); @@ -838,9 +827,8 @@ unsigned AggressiveAntiDepBreaker::BreakAntiDependencies( } else { // No anti-dep breaking for implicit deps MachineOperand *AntiDepOp = MI->findRegisterDefOperand(AntiDepReg); - assert(AntiDepOp != NULL && - "Can't find index for defined register operand"); - if ((AntiDepOp == NULL) || AntiDepOp->isImplicit()) { + assert(AntiDepOp && "Can't find index for defined register operand"); + if (!AntiDepOp || AntiDepOp->isImplicit()) { DEBUG(dbgs() << " (implicit)\n"); continue; }