diff options
Diffstat (limited to 'llvm/lib/CodeGen')
-rw-r--r-- | llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp | 43 | ||||
-rw-r--r-- | llvm/lib/CodeGen/LiveDebugValues.cpp | 211 | ||||
-rw-r--r-- | llvm/lib/CodeGen/MachineInstr.cpp | 54 |
3 files changed, 216 insertions, 92 deletions
diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp index b8d4466eaba..be666add18b 100644 --- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp @@ -746,41 +746,20 @@ static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) { const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo(); // Check for spills and reloads - int FI; - - const MachineFrameInfo &MFI = MF->getFrameInfo(); - - auto getSize = - [&MFI](const SmallVectorImpl<const MachineMemOperand *> &Accesses) { - unsigned Size = 0; - for (auto A : Accesses) - if (MFI.isSpillSlotObjectIndex( - cast<FixedStackPseudoSourceValue>(A->getPseudoValue()) - ->getFrameIndex())) - Size += A->getSize(); - return Size; - }; // We assume a single instruction only has a spill or reload, not // both. - const MachineMemOperand *MMO; - SmallVector<const MachineMemOperand *, 2> Accesses; - if (TII->isLoadFromStackSlotPostFE(MI, FI)) { - if (MFI.isSpillSlotObjectIndex(FI)) { - MMO = *MI.memoperands_begin(); - CommentOS << MMO->getSize() << "-byte Reload\n"; - } - } else if (TII->hasLoadFromStackSlot(MI, Accesses)) { - if (auto Size = getSize(Accesses)) - CommentOS << Size << "-byte Folded Reload\n"; - } else if (TII->isStoreToStackSlotPostFE(MI, FI)) { - if (MFI.isSpillSlotObjectIndex(FI)) { - MMO = *MI.memoperands_begin(); - CommentOS << MMO->getSize() << "-byte Spill\n"; - } - } else if (TII->hasStoreToStackSlot(MI, Accesses)) { - if (auto Size = getSize(Accesses)) - CommentOS << Size << "-byte Folded Spill\n"; + Optional<unsigned> Size; + if ((Size = MI.getRestoreSize(TII))) { + CommentOS << *Size << "-byte Reload\n"; + } else if ((Size = MI.getFoldedRestoreSize(TII))) { + if (*Size) + CommentOS << *Size << "-byte Folded Reload\n"; + } else if ((Size = MI.getSpillSize(TII))) { + CommentOS << *Size << "-byte Spill\n"; + } else if ((Size = MI.getFoldedSpillSize(TII))) { + if (*Size) + CommentOS << *Size << "-byte Folded Spill\n"; } // Check for spill-induced copies diff --git a/llvm/lib/CodeGen/LiveDebugValues.cpp b/llvm/lib/CodeGen/LiveDebugValues.cpp index 21791a92e74..449f10c7ef7 100644 --- a/llvm/lib/CodeGen/LiveDebugValues.cpp +++ b/llvm/lib/CodeGen/LiveDebugValues.cpp @@ -34,13 +34,14 @@ #include "llvm/CodeGen/MachineMemOperand.h" #include "llvm/CodeGen/MachineOperand.h" #include "llvm/CodeGen/PseudoSourceValue.h" +#include "llvm/CodeGen/RegisterScavenging.h" #include "llvm/CodeGen/TargetFrameLowering.h" #include "llvm/CodeGen/TargetInstrInfo.h" #include "llvm/CodeGen/TargetLowering.h" #include "llvm/CodeGen/TargetRegisterInfo.h" #include "llvm/CodeGen/TargetSubtargetInfo.h" -#include "llvm/CodeGen/RegisterScavenging.h" #include "llvm/Config/llvm-config.h" +#include "llvm/IR/DIBuilder.h" #include "llvm/IR/DebugInfoMetadata.h" #include "llvm/IR/DebugLoc.h" #include "llvm/IR/Function.h" @@ -85,6 +86,8 @@ private: BitVector CalleeSavedRegs; LexicalScopes LS; + enum struct TransferKind { TransferCopy, TransferSpill, TransferRestore }; + /// Keeps track of lexical scopes associated with a user value's source /// location. class UserValueScopes { @@ -124,15 +127,30 @@ private: /// A pair of debug variable and value location. struct VarLoc { + // The location at which a spilled variable resides. It consists of a + // register and an offset. + struct SpillLoc { + unsigned SpillBase; + int SpillOffset; + bool operator==(const SpillLoc &Other) const { + return SpillBase == Other.SpillBase && SpillOffset == Other.SpillOffset; + } + }; + const DebugVariable Var; const MachineInstr &MI; ///< Only used for cloning a new DBG_VALUE. mutable UserValueScopes UVS; - enum { InvalidKind = 0, RegisterKind } Kind = InvalidKind; + enum VarLocKind { + InvalidKind = 0, + RegisterKind, + SpillLocKind + } Kind = InvalidKind; /// The value location. Stored separately to avoid repeatedly /// extracting it from MI. union { uint64_t RegNo; + SpillLoc SpillLocation; uint64_t Hash; } Loc; @@ -149,6 +167,17 @@ private: } } + /// The constructor for spill locations. + VarLoc(const MachineInstr &MI, unsigned SpillBase, int SpillOffset, + LexicalScopes &LS) + : Var(MI.getDebugVariable(), MI.getDebugLoc()->getInlinedAt()), MI(MI), + UVS(MI.getDebugLoc(), LS) { + assert(MI.isDebugValue() && "not a DBG_VALUE"); + assert(MI.getNumOperands() == 4 && "malformed DBG_VALUE"); + Kind = SpillLocKind; + Loc.SpillLocation = {SpillBase, SpillOffset}; + } + /// If this variable is described by a register, return it, /// otherwise return 0. unsigned isDescribedByReg() const { @@ -236,15 +265,23 @@ private: bool isSpillInstruction(const MachineInstr &MI, MachineFunction *MF, unsigned &Reg); - int extractSpillBaseRegAndOffset(const MachineInstr &MI, unsigned &Reg); + /// If a given instruction is identified as a spill, return the spill location + /// and set \p Reg to the spilled register. + Optional<VarLoc::SpillLoc> isRestoreInstruction(const MachineInstr &MI, + MachineFunction *MF, + unsigned &Reg); + /// Given a spill instruction, extract the register and offset used to + /// address the spill location in a target independent way. + VarLoc::SpillLoc extractSpillBaseRegAndOffset(const MachineInstr &MI); void insertTransferDebugPair(MachineInstr &MI, OpenRangesSet &OpenRanges, TransferMap &Transfers, VarLocMap &VarLocIDs, - unsigned OldVarID, unsigned NewReg = 0); + unsigned OldVarID, TransferKind Kind, + unsigned NewReg = 0); void transferDebugValue(const MachineInstr &MI, OpenRangesSet &OpenRanges, VarLocMap &VarLocIDs); - void transferSpillInst(MachineInstr &MI, OpenRangesSet &OpenRanges, - VarLocMap &VarLocIDs, TransferMap &Transfers); + void transferSpillOrRestoreInst(MachineInstr &MI, OpenRangesSet &OpenRanges, + VarLocMap &VarLocIDs, TransferMap &Transfers); void transferRegisterCopy(MachineInstr &MI, OpenRangesSet &OpenRanges, VarLocMap &VarLocIDs, TransferMap &Transfers); void transferRegisterDef(MachineInstr &MI, OpenRangesSet &OpenRanges, @@ -338,10 +375,8 @@ void LiveDebugValues::printVarLocInMBB(const MachineFunction &MF, } #endif -/// Given a spill instruction, extract the register and offset used to -/// address the spill location in a target independent way. -int LiveDebugValues::extractSpillBaseRegAndOffset(const MachineInstr &MI, - unsigned &Reg) { +LiveDebugValues::VarLoc::SpillLoc +LiveDebugValues::extractSpillBaseRegAndOffset(const MachineInstr &MI) { assert(MI.hasOneMemOperand() && "Spill instruction does not have exactly one memory operand?"); auto MMOI = MI.memoperands_begin(); @@ -350,7 +385,9 @@ int LiveDebugValues::extractSpillBaseRegAndOffset(const MachineInstr &MI, "Inconsistent memory operand in spill instruction"); int FI = cast<FixedStackPseudoSourceValue>(PVal)->getFrameIndex(); const MachineBasicBlock *MBB = MI.getParent(); - return TFI->getFrameIndexReference(*MBB->getParent(), FI, Reg); + unsigned Reg; + int Offset = TFI->getFrameIndexReference(*MBB->getParent(), FI, Reg); + return {Reg, Offset}; } /// End all previous ranges related to @MI and start a new range from @MI @@ -386,11 +423,28 @@ void LiveDebugValues::transferDebugValue(const MachineInstr &MI, /// otherwise it is variable's location on the stack. void LiveDebugValues::insertTransferDebugPair( MachineInstr &MI, OpenRangesSet &OpenRanges, TransferMap &Transfers, - VarLocMap &VarLocIDs, unsigned OldVarID, unsigned NewReg) { + VarLocMap &VarLocIDs, unsigned OldVarID, TransferKind Kind, + unsigned NewReg) { const MachineInstr *DMI = &VarLocIDs[OldVarID].MI; MachineFunction *MF = MI.getParent()->getParent(); MachineInstr *NewDMI; - if (NewReg) { + + auto ProcessVarLoc = [&MI, &OpenRanges, &Transfers, + &VarLocIDs](VarLoc &VL, MachineInstr *NewDMI) { + unsigned LocId = VarLocIDs.insert(VL); + OpenRanges.insert(LocId, VL.Var); + // The newly created DBG_VALUE instruction NewDMI must be inserted after + // MI. Keep track of the pairing. + TransferDebugPair MIP = {&MI, NewDMI}; + Transfers.push_back(MIP); + }; + + // End all previous ranges of Var. + OpenRanges.erase(VarLocIDs[OldVarID].Var); + switch (Kind) { + case TransferKind::TransferCopy: { + assert(NewReg && + "No register supplied when handling a copy of a debug value"); // Create a DBG_VALUE instruction to describe the Var in its new // register location. NewDMI = BuildMI(*MF, DMI->getDebugLoc(), DMI->getDesc(), @@ -398,33 +452,43 @@ void LiveDebugValues::insertTransferDebugPair( DMI->getDebugVariable(), DMI->getDebugExpression()); if (DMI->isIndirectDebugValue()) NewDMI->getOperand(1).setImm(DMI->getOperand(1).getImm()); + VarLoc VL(*NewDMI, LS); + ProcessVarLoc(VL, NewDMI); LLVM_DEBUG(dbgs() << "Creating DBG_VALUE inst for register copy: "; NewDMI->print(dbgs(), false, false, false, TII)); - } else { + return; + } + case TransferKind::TransferSpill: { // Create a DBG_VALUE instruction to describe the Var in its spilled // location. - unsigned SpillBase; - int SpillOffset = extractSpillBaseRegAndOffset(MI, SpillBase); - auto *SpillExpr = DIExpression::prepend(DMI->getDebugExpression(), - DIExpression::NoDeref, SpillOffset); - NewDMI = BuildMI(*MF, DMI->getDebugLoc(), DMI->getDesc(), true, SpillBase, - DMI->getDebugVariable(), SpillExpr); + VarLoc::SpillLoc SpillLocation = extractSpillBaseRegAndOffset(MI); + auto *SpillExpr = + DIExpression::prepend(DMI->getDebugExpression(), DIExpression::NoDeref, + SpillLocation.SpillOffset); + NewDMI = + BuildMI(*MF, DMI->getDebugLoc(), DMI->getDesc(), true, + SpillLocation.SpillBase, DMI->getDebugVariable(), SpillExpr); + VarLoc VL(*NewDMI, SpillLocation.SpillBase, SpillLocation.SpillOffset, LS); + ProcessVarLoc(VL, NewDMI); LLVM_DEBUG(dbgs() << "Creating DBG_VALUE inst for spill: "; NewDMI->print(dbgs(), false, false, false, TII)); + return; } - - // The newly created DBG_VALUE instruction NewDMI must be inserted after - // MI. Keep track of the pairing. - TransferDebugPair MIP = {&MI, NewDMI}; - Transfers.push_back(MIP); - - // End all previous ranges of Var. - OpenRanges.erase(VarLocIDs[OldVarID].Var); - - // Add the VarLoc to OpenRanges. - VarLoc VL(*NewDMI, LS); - unsigned LocID = VarLocIDs.insert(VL); - OpenRanges.insert(LocID, VL.Var); + case TransferKind::TransferRestore: { + assert(NewReg && + "No register supplied when handling a restore of a debug value"); + MachineFunction *MF = MI.getMF(); + DIBuilder DIB(*const_cast<Function &>(MF->getFunction()).getParent()); + NewDMI = BuildMI(*MF, DMI->getDebugLoc(), DMI->getDesc(), false, NewReg, + DMI->getDebugVariable(), DIB.createExpression()); + VarLoc VL(*NewDMI, LS); + ProcessVarLoc(VL, NewDMI); + LLVM_DEBUG(dbgs() << "Creating DBG_VALUE inst for register restore: "; + NewDMI->print(dbgs(), false, false, false, TII)); + return; + } + } + llvm_unreachable("Invalid transfer kind"); } /// A definition of a register may mark the end of a range. @@ -470,24 +534,15 @@ void LiveDebugValues::transferRegisterDef(MachineInstr &MI, /// other spills). We do not handle this yet (more than one memory operand). bool LiveDebugValues::isSpillInstruction(const MachineInstr &MI, MachineFunction *MF, unsigned &Reg) { - const MachineFrameInfo &FrameInfo = MF->getFrameInfo(); - int FI; SmallVector<const MachineMemOperand*, 1> Accesses; // TODO: Handle multiple stores folded into one. if (!MI.hasOneMemOperand()) return false; - // To identify a spill instruction, use the same criteria as in AsmPrinter. - if (!((TII->isStoreToStackSlotPostFE(MI, FI) && - FrameInfo.isSpillSlotObjectIndex(FI)) || - (TII->hasStoreToStackSlot(MI, Accesses) && - llvm::any_of(Accesses, [&FrameInfo](const MachineMemOperand *MMO) { - return FrameInfo.isSpillSlotObjectIndex( - cast<FixedStackPseudoSourceValue>(MMO->getPseudoValue()) - ->getFrameIndex()); - })))) - return false; + if (!MI.getSpillSize(TII) && !MI.getFoldedSpillSize(TII)) + return false; // This is not a spill instruction, since no valid size was + // returned from either function. auto isKilledReg = [&](const MachineOperand MO, unsigned &Reg) { if (!MO.isReg() || !MO.isUse()) { @@ -524,29 +579,67 @@ bool LiveDebugValues::isSpillInstruction(const MachineInstr &MI, return false; } +Optional<LiveDebugValues::VarLoc::SpillLoc> +LiveDebugValues::isRestoreInstruction(const MachineInstr &MI, + MachineFunction *MF, unsigned &Reg) { + if (!MI.hasOneMemOperand()) + return None; + + // FIXME: Handle folded restore instructions with more than one memory + // operand. + if (MI.getRestoreSize(TII)) { + Reg = MI.getOperand(0).getReg(); + return extractSpillBaseRegAndOffset(MI); + } + return None; +} + /// A spilled register may indicate that we have to end the current range of /// a variable and create a new one for the spill location. +/// A restored register may indicate the reverse situation. /// We don't want to insert any instructions in process(), so we just create /// the DBG_VALUE without inserting it and keep track of it in \p Transfers. /// It will be inserted into the BB when we're done iterating over the /// instructions. -void LiveDebugValues::transferSpillInst(MachineInstr &MI, - OpenRangesSet &OpenRanges, - VarLocMap &VarLocIDs, - TransferMap &Transfers) { - unsigned Reg; +void LiveDebugValues::transferSpillOrRestoreInst(MachineInstr &MI, + OpenRangesSet &OpenRanges, + VarLocMap &VarLocIDs, + TransferMap &Transfers) { MachineFunction *MF = MI.getMF(); - if (!isSpillInstruction(MI, MF, Reg)) - return; + TransferKind TKind; + unsigned Reg; + Optional<VarLoc::SpillLoc> Loc; - // Check if the register is the location of a debug value. + LLVM_DEBUG(dbgs() << "Examining instruction: "; MI.dump();); + + if (isSpillInstruction(MI, MF, Reg)) { + TKind = TransferKind::TransferSpill; + LLVM_DEBUG(dbgs() << "Recognized as spill: "; MI.dump();); + LLVM_DEBUG(dbgs() << "Register: " << Reg << " " << printReg(Reg, TRI) + << "\n"); + } else { + if (!(Loc = isRestoreInstruction(MI, MF, Reg))) + return; + TKind = TransferKind::TransferRestore; + LLVM_DEBUG(dbgs() << "Recognized as restore: "; MI.dump();); + LLVM_DEBUG(dbgs() << "Register: " << Reg << " " << printReg(Reg, TRI) + << "\n"); + } + // Check if the register or spill location is the location of a debug value. for (unsigned ID : OpenRanges.getVarLocs()) { - if (VarLocIDs[ID].isDescribedByReg() == Reg) { + if (TKind == TransferKind::TransferSpill && + VarLocIDs[ID].isDescribedByReg() == Reg) { LLVM_DEBUG(dbgs() << "Spilling Register " << printReg(Reg, TRI) << '(' << VarLocIDs[ID].Var.getVar()->getName() << ")\n"); - insertTransferDebugPair(MI, OpenRanges, Transfers, VarLocIDs, ID); - return; - } + } else if (TKind == TransferKind::TransferRestore && + VarLocIDs[ID].Loc.SpillLocation == *Loc) { + LLVM_DEBUG(dbgs() << "Restoring Register " << printReg(Reg, TRI) << '(' + << VarLocIDs[ID].Var.getVar()->getName() << ")\n"); + } else + continue; + insertTransferDebugPair(MI, OpenRanges, Transfers, VarLocIDs, ID, TKind, + Reg); + return; } } @@ -584,7 +677,7 @@ void LiveDebugValues::transferRegisterCopy(MachineInstr &MI, for (unsigned ID : OpenRanges.getVarLocs()) { if (VarLocIDs[ID].isDescribedByReg() == SrcReg) { insertTransferDebugPair(MI, OpenRanges, Transfers, VarLocIDs, ID, - DestReg); + TransferKind::TransferCopy, DestReg); return; } } @@ -624,7 +717,7 @@ bool LiveDebugValues::process(MachineInstr &MI, OpenRangesSet &OpenRanges, transferRegisterDef(MI, OpenRanges, VarLocIDs); if (transferChanges) { transferRegisterCopy(MI, OpenRanges, VarLocIDs, Transfers); - transferSpillInst(MI, OpenRanges, VarLocIDs, Transfers); + transferSpillOrRestoreInst(MI, OpenRanges, VarLocIDs, Transfers); } Changed = transferTerminatorInst(MI, OpenRanges, OutLocs, VarLocIDs); return Changed; diff --git a/llvm/lib/CodeGen/MachineInstr.cpp b/llvm/lib/CodeGen/MachineInstr.cpp index ca43804481b..7ef931a6636 100644 --- a/llvm/lib/CodeGen/MachineInstr.cpp +++ b/llvm/lib/CodeGen/MachineInstr.cpp @@ -25,6 +25,7 @@ #include "llvm/Analysis/MemoryLocation.h" #include "llvm/CodeGen/GlobalISel/RegisterBank.h" #include "llvm/CodeGen/MachineBasicBlock.h" +#include "llvm/CodeGen/MachineFrameInfo.h" #include "llvm/CodeGen/MachineFunction.h" #include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/CodeGen/MachineInstrBundle.h" @@ -49,9 +50,9 @@ #include "llvm/IR/Metadata.h" #include "llvm/IR/Module.h" #include "llvm/IR/ModuleSlotTracker.h" +#include "llvm/IR/Operator.h" #include "llvm/IR/Type.h" #include "llvm/IR/Value.h" -#include "llvm/IR/Operator.h" #include "llvm/MC/MCInstrDesc.h" #include "llvm/MC/MCRegisterInfo.h" #include "llvm/MC/MCSymbol.h" @@ -2102,3 +2103,54 @@ void MachineInstr::changeDebugValuesDefReg(unsigned Reg) { for (auto *DBI : DbgValues) DBI->getOperand(0).setReg(Reg); } + +using MMOList = SmallVector<const MachineMemOperand *, 2>; + +static unsigned getSpillSlotSize(MMOList &Accesses, + const MachineFrameInfo &MFI) { + unsigned Size = 0; + for (auto A : Accesses) + if (MFI.isSpillSlotObjectIndex( + cast<FixedStackPseudoSourceValue>(A->getPseudoValue()) + ->getFrameIndex())) + Size += A->getSize(); + return Size; +} + +Optional<unsigned> +MachineInstr::getSpillSize(const TargetInstrInfo *TII) const { + int FI; + if (TII->isStoreToStackSlotPostFE(*this, FI)) { + const MachineFrameInfo &MFI = getMF()->getFrameInfo(); + if (MFI.isSpillSlotObjectIndex(FI)) + return (*memoperands_begin())->getSize(); + } + return None; +} + +Optional<unsigned> +MachineInstr::getFoldedSpillSize(const TargetInstrInfo *TII) const { + MMOList Accesses; + if (TII->hasStoreToStackSlot(*this, Accesses)) + return getSpillSlotSize(Accesses, getMF()->getFrameInfo()); + return None; +} + +Optional<unsigned> +MachineInstr::getRestoreSize(const TargetInstrInfo *TII) const { + int FI; + if (TII->isLoadFromStackSlotPostFE(*this, FI)) { + const MachineFrameInfo &MFI = getMF()->getFrameInfo(); + if (MFI.isSpillSlotObjectIndex(FI)) + return (*memoperands_begin())->getSize(); + } + return None; +} + +Optional<unsigned> +MachineInstr::getFoldedRestoreSize(const TargetInstrInfo *TII) const { + MMOList Accesses; + if (TII->hasLoadFromStackSlot(*this, Accesses)) + return getSpillSlotSize(Accesses, getMF()->getFrameInfo()); + return None; +} |