X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=blobdiff_plain;f=lib%2FCodeGen%2FLiveDebugVariables.cpp;h=6dac7dbd15bf7e9cf924e605d774034e72d5940f;hp=20e997ae377bdb6935959cf3c206548e40686ffa;hb=5666fc71f0e2ed2c0400d8bca079a1dd3f33fe53;hpb=1744e476ec3df0350a1163bf2c6439ea21aefbba diff --git a/lib/CodeGen/LiveDebugVariables.cpp b/lib/CodeGen/LiveDebugVariables.cpp index 20e997ae377..6dac7dbd15b 100644 --- a/lib/CodeGen/LiveDebugVariables.cpp +++ b/lib/CodeGen/LiveDebugVariables.cpp @@ -19,31 +19,39 @@ // //===----------------------------------------------------------------------===// -#define DEBUG_TYPE "livedebug" #include "LiveDebugVariables.h" -#include "VirtRegMap.h" -#include "llvm/Constants.h" -#include "llvm/Metadata.h" -#include "llvm/Value.h" #include "llvm/ADT/IntervalMap.h" +#include "llvm/ADT/Statistic.h" +#include "llvm/CodeGen/LexicalScopes.h" #include "llvm/CodeGen/LiveIntervalAnalysis.h" #include "llvm/CodeGen/MachineDominators.h" #include "llvm/CodeGen/MachineFunction.h" #include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/Passes.h" +#include "llvm/CodeGen/VirtRegMap.h" +#include "llvm/IR/Constants.h" +#include "llvm/IR/DebugInfo.h" +#include "llvm/IR/Metadata.h" +#include "llvm/IR/Value.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/Debug.h" +#include "llvm/Support/raw_ostream.h" #include "llvm/Target/TargetInstrInfo.h" #include "llvm/Target/TargetMachine.h" #include "llvm/Target/TargetRegisterInfo.h" +#include "llvm/Target/TargetSubtargetInfo.h" +#include using namespace llvm; +#define DEBUG_TYPE "livedebug" + static cl::opt EnableLDV("live-debug-variables", cl::init(true), cl::desc("Enable the live debug variables pass"), cl::Hidden); +STATISTIC(NumInsertedDebugValues, "Number of DBG_VALUEs inserted"); char LiveDebugVariables::ID = 0; INITIALIZE_PASS_BEGIN(LiveDebugVariables, "livedebugvars", @@ -60,13 +68,34 @@ void LiveDebugVariables::getAnalysisUsage(AnalysisUsage &AU) const { MachineFunctionPass::getAnalysisUsage(AU); } -LiveDebugVariables::LiveDebugVariables() : MachineFunctionPass(ID), pImpl(0) { +LiveDebugVariables::LiveDebugVariables() : MachineFunctionPass(ID), pImpl(nullptr) { initializeLiveDebugVariablesPass(*PassRegistry::getPassRegistry()); } /// LocMap - Map of where a user value is live, and its location. typedef IntervalMap LocMap; +namespace { +/// UserValueScopes - Keeps track of lexical scopes associated with a +/// user value's source location. +class UserValueScopes { + DebugLoc DL; + LexicalScopes &LS; + SmallPtrSet LBlocks; + +public: + UserValueScopes(DebugLoc D, LexicalScopes &L) : DL(D), LS(L) {} + + /// dominates - Return true if current scope dominates at least one machine + /// instruction in a given machine basic block. + bool dominates(MachineBasicBlock *MBB) { + if (LBlocks.empty()) + LS.getMachineBasicBlocks(DL, LBlocks); + return LBlocks.count(MBB) != 0 || LS.dominates(DL, MBB); + } +}; +} // end anonymous namespace + /// UserValue - A user value is a part of a debug info user variable. /// /// A DBG_VALUE instruction notes that (a sub-register of) a virtual register @@ -79,8 +108,10 @@ typedef IntervalMap LocMap; namespace { class LDVImpl; class UserValue { - const MDNode *variable; ///< The debug info variable we are part of. + const MDNode *Variable; ///< The debug info variable we are part of. + const MDNode *Expression; ///< Any complex address expression. unsigned offset; ///< Byte offset into variable. + bool IsIndirect; ///< true if this is a register-indirect+offset value. DebugLoc dl; ///< The debug location for the variable. This is ///< used by dwarf writer to find lexical scope. UserValue *leader; ///< Equivalence class leader. @@ -101,16 +132,17 @@ class UserValue { void insertDebugValue(MachineBasicBlock *MBB, SlotIndex Idx, unsigned LocNo, LiveIntervals &LIS, const TargetInstrInfo &TII); - /// insertDebugKill - Insert an undef DBG_VALUE into MBB at Idx. - void insertDebugKill(MachineBasicBlock *MBB, SlotIndex Idx, - LiveIntervals &LIS, const TargetInstrInfo &TII); + /// splitLocation - Replace OldLocNo ranges with NewRegs ranges where NewRegs + /// is live. Returns true if any changes were made. + bool splitLocation(unsigned OldLocNo, ArrayRef NewRegs, + LiveIntervals &LIS); public: /// UserValue - Create a new UserValue. - UserValue(const MDNode *var, unsigned o, DebugLoc L, - LocMap::Allocator &alloc) - : variable(var), offset(o), dl(L), leader(this), next(0), locInts(alloc) - {} + UserValue(const MDNode *var, const MDNode *expr, unsigned o, bool i, + DebugLoc L, LocMap::Allocator &alloc) + : Variable(var), Expression(expr), offset(o), IsIndirect(i), dl(L), + leader(this), next(nullptr), locInts(alloc) {} /// getLeader - Get the leader of this value's equivalence class. UserValue *getLeader() { @@ -123,9 +155,11 @@ public: /// getNext - Return the next UserValue in the equivalence class. UserValue *getNext() const { return next; } - /// match - Does this UserValue match the aprameters? - bool match(const MDNode *Var, unsigned Offset) const { - return Var == variable && Offset == offset; + /// match - Does this UserValue match the parameters? + bool match(const MDNode *Var, const MDNode *Expr, const DILocation *IA, + unsigned Offset, bool indirect) const { + return Var == Variable && Expr == Expression && dl->getInlinedAt() == IA && + Offset == offset && indirect == IsIndirect; } /// merge - Merge equivalence classes. @@ -179,6 +213,9 @@ public: LocMap::iterator I = locInts.find(Idx); if (!I.valid() || I.start() != Idx) I.insert(Idx, Idx.getNextSlot(), getLocationNo(LocMO)); + else + // A later DBG_VALUE at the same SlotIndex overrides the old location. + I.setValue(getLocationNo(LocMO)); } /// extendDef - Extend the current definition as far as possible down the @@ -187,15 +224,16 @@ public: /// End points where VNI is no longer live are added to Kills. /// @param Idx Starting point for the definition. /// @param LocNo Location number to propagate. - /// @param LI Restrict liveness to where LI has the value VNI. May be null. - /// @param VNI When LI is not null, this is the value to restrict to. + /// @param LR Restrict liveness to where LR has the value VNI. May be null. + /// @param VNI When LR is not null, this is the value to restrict to. /// @param Kills Append end points of VNI's live range to Kills. /// @param LIS Live intervals analysis. /// @param MDT Dominator tree. void extendDef(SlotIndex Idx, unsigned LocNo, - LiveInterval *LI, const VNInfo *VNI, + LiveRange *LR, const VNInfo *VNI, SmallVectorImpl *Kills, - LiveIntervals &LIS, MachineDominatorTree &MDT); + LiveIntervals &LIS, MachineDominatorTree &MDT, + UserValueScopes &UVS); /// addDefsFromCopies - The value in LI/LocNo may be copies to other /// registers. Determine if any of the copies are available at the kill @@ -212,27 +250,26 @@ public: /// computeIntervals - Compute the live intervals of all locations after /// collecting all their def points. - void computeIntervals(MachineRegisterInfo &MRI, - LiveIntervals &LIS, MachineDominatorTree &MDT); + void computeIntervals(MachineRegisterInfo &MRI, const TargetRegisterInfo &TRI, + LiveIntervals &LIS, MachineDominatorTree &MDT, + UserValueScopes &UVS); - /// renameRegister - Update locations to rewrite OldReg as NewReg:SubIdx. - void renameRegister(unsigned OldReg, unsigned NewReg, unsigned SubIdx, - const TargetRegisterInfo *TRI); + /// splitRegister - Replace OldReg ranges with NewRegs ranges where NewRegs is + /// live. Returns true if any changes were made. + bool splitRegister(unsigned OldLocNo, ArrayRef NewRegs, + LiveIntervals &LIS); /// rewriteLocations - Rewrite virtual register locations according to the /// provided virtual register map. void rewriteLocations(VirtRegMap &VRM, const TargetRegisterInfo &TRI); - /// emitDebugVariables - Recreate DBG_VALUE instruction from data structures. + /// emitDebugValues - Recreate DBG_VALUE instruction from data structures. void emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS, const TargetInstrInfo &TRI); - /// findDebugLoc - Return DebugLoc used for this DBG_VALUE instruction. A - /// variable may have more than one corresponding DBG_VALUE instructions. - /// Only first one needs DebugLoc to identify variable's lexical scope - /// in source file. - DebugLoc findDebugLoc(); - void print(raw_ostream&, const TargetRegisterInfo*); + /// getDebugLoc - Return DebugLoc of this UserValue. + DebugLoc getDebugLoc() { return dl;} + void print(raw_ostream &, const TargetRegisterInfo *); }; } // namespace @@ -243,11 +280,17 @@ class LDVImpl { LocMap::Allocator allocator; MachineFunction *MF; LiveIntervals *LIS; + LexicalScopes LS; MachineDominatorTree *MDT; const TargetRegisterInfo *TRI; + /// Whether emitDebugValues is called. + bool EmitDone; + /// Whether the machine function is modified during the pass. + bool ModifiedMF; + /// userValues - All allocated UserValue instances. - SmallVector userValues; + SmallVector, 8> userValues; /// Map virtual register to eq class leader. typedef DenseMap VRMap; @@ -258,7 +301,8 @@ class LDVImpl { UVMap userVarMap; /// getUserValue - Find or create a UserValue. - UserValue *getUserValue(const MDNode *Var, unsigned Offset, DebugLoc DL); + UserValue *getUserValue(const MDNode *Var, const MDNode *Expr, + unsigned Offset, bool IsIndirect, DebugLoc DL); /// lookupVirtReg - Find the EC leader for VirtReg or null. UserValue *lookupVirtReg(unsigned VirtReg); @@ -280,33 +324,79 @@ class LDVImpl { void computeIntervals(); public: - LDVImpl(LiveDebugVariables *ps) : pass(*ps) {} + LDVImpl(LiveDebugVariables *ps) + : pass(*ps), MF(nullptr), EmitDone(false), ModifiedMF(false) {} bool runOnMachineFunction(MachineFunction &mf); - /// clear - Relase all memory. + /// clear - Release all memory. void clear() { - DeleteContainerPointers(userValues); + MF = nullptr; userValues.clear(); virtRegToEqClass.clear(); userVarMap.clear(); + // Make sure we call emitDebugValues if the machine function was modified. + assert((!ModifiedMF || EmitDone) && + "Dbg values are not emitted in LDV"); + EmitDone = false; + ModifiedMF = false; + LS.reset(); } /// mapVirtReg - Map virtual register to an equivalence class. void mapVirtReg(unsigned VirtReg, UserValue *EC); - /// renameRegister - Replace all references to OldReg wiht NewReg:SubIdx. - void renameRegister(unsigned OldReg, unsigned NewReg, unsigned SubIdx); + /// splitRegister - Replace all references to OldReg with NewRegs. + void splitRegister(unsigned OldReg, ArrayRef NewRegs); - /// emitDebugVariables - Recreate DBG_VALUE instruction from data structures. + /// emitDebugValues - Recreate DBG_VALUE instruction from data structures. void emitDebugValues(VirtRegMap *VRM); void print(raw_ostream&); }; } // namespace +static void printDebugLoc(DebugLoc DL, raw_ostream &CommentOS, + const LLVMContext &Ctx) { + if (!DL) + return; + + auto *Scope = cast(DL.getScope()); + // Omit the directory, because it's likely to be long and uninteresting. + CommentOS << Scope->getFilename(); + CommentOS << ':' << DL.getLine(); + if (DL.getCol() != 0) + CommentOS << ':' << DL.getCol(); + + DebugLoc InlinedAtDL = DL.getInlinedAt(); + if (!InlinedAtDL) + return; + + CommentOS << " @[ "; + printDebugLoc(InlinedAtDL, CommentOS, Ctx); + CommentOS << " ]"; +} + +static void printExtendedName(raw_ostream &OS, const DILocalVariable *V, + const DILocation *DL) { + const LLVMContext &Ctx = V->getContext(); + StringRef Res = V->getName(); + if (!Res.empty()) + OS << Res << "," << V->getLine(); + if (auto *InlinedAt = DL->getInlinedAt()) { + if (DebugLoc InlinedAtDL = InlinedAt) { + OS << " @["; + printDebugLoc(InlinedAtDL, OS, Ctx); + OS << "]"; + } + } +} + void UserValue::print(raw_ostream &OS, const TargetRegisterInfo *TRI) { - if (const MDString *MDS = dyn_cast(variable->getOperand(2))) - OS << "!\"" << MDS->getString() << "\"\t"; + auto *DV = cast(Variable); + OS << "!\""; + printExtendedName(OS, DV, dl); + + OS << "\"\t"; if (offset) OS << '+' << offset; for (LocMap::const_iterator I = locInts.begin(); I.valid(); ++I) { @@ -316,8 +406,10 @@ void UserValue::print(raw_ostream &OS, const TargetRegisterInfo *TRI) { else OS << I.value(); } - for (unsigned i = 0, e = locations.size(); i != e; ++i) - OS << " Loc" << i << '=' << locations[i]; + for (unsigned i = 0, e = locations.size(); i != e; ++i) { + OS << " Loc" << i << '='; + locations[i].print(OS, TRI); + } OS << '\n'; } @@ -362,19 +454,21 @@ void UserValue::mapVirtRegs(LDVImpl *LDV) { LDV->mapVirtReg(locations[i].getReg(), this); } -UserValue *LDVImpl::getUserValue(const MDNode *Var, unsigned Offset, +UserValue *LDVImpl::getUserValue(const MDNode *Var, const MDNode *Expr, + unsigned Offset, bool IsIndirect, DebugLoc DL) { UserValue *&Leader = userVarMap[Var]; if (Leader) { UserValue *UV = Leader->getLeader(); Leader = UV; for (; UV; UV = UV->getNext()) - if (UV->match(Var, Offset)) + if (UV->match(Var, Expr, DL->getInlinedAt(), Offset, IsIndirect)) return UV; } - UserValue *UV = new UserValue(Var, Offset, DL, allocator); - userValues.push_back(UV); + userValues.push_back( + make_unique(Var, Expr, Offset, IsIndirect, DL, allocator)); + UserValue *UV = userValues.back().get(); Leader = UserValue::merge(Leader, UV); return UV; } @@ -388,21 +482,26 @@ void LDVImpl::mapVirtReg(unsigned VirtReg, UserValue *EC) { UserValue *LDVImpl::lookupVirtReg(unsigned VirtReg) { if (UserValue *UV = virtRegToEqClass.lookup(VirtReg)) return UV->getLeader(); - return 0; + return nullptr; } bool LDVImpl::handleDebugValue(MachineInstr *MI, SlotIndex Idx) { // DBG_VALUE loc, offset, variable - if (MI->getNumOperands() != 3 || - !MI->getOperand(1).isImm() || !MI->getOperand(2).isMetadata()) { + if (MI->getNumOperands() != 4 || + !(MI->getOperand(1).isReg() || MI->getOperand(1).isImm()) || + !MI->getOperand(2).isMetadata()) { DEBUG(dbgs() << "Can't handle " << *MI); return false; } // Get or create the UserValue for (variable,offset). - unsigned Offset = MI->getOperand(1).getImm(); - const MDNode *Var = MI->getOperand(2).getMetadata(); - UserValue *UV = getUserValue(Var, Offset, MI->getDebugLoc()); + bool IsIndirect = MI->isIndirectDebugValue(); + unsigned Offset = IsIndirect ? MI->getOperand(1).getImm() : 0; + const MDNode *Var = MI->getDebugVariable(); + const MDNode *Expr = MI->getDebugExpression(); + //here. + UserValue *UV = + getUserValue(Var, Expr, Offset, IsIndirect, MI->getDebugLoc()); UV->addDef(Idx, MI->getOperand(0)); return true; } @@ -411,7 +510,7 @@ bool LDVImpl::collectDebugValues(MachineFunction &mf) { bool Changed = false; for (MachineFunction::iterator MFI = mf.begin(), MFE = mf.end(); MFI != MFE; ++MFI) { - MachineBasicBlock *MBB = MFI; + MachineBasicBlock *MBB = &*MFI; for (MachineBasicBlock::iterator MBBI = MBB->begin(), MBBE = MBB->end(); MBBI != MBBE;) { if (!MBBI->isDebugValue()) { @@ -421,7 +520,7 @@ bool LDVImpl::collectDebugValues(MachineFunction &mf) { // DBG_VALUE has no slot index, use the previous instruction instead. SlotIndex Idx = MBBI == MBB->begin() ? LIS->getMBBStartIdx(MBB) : - LIS->getInstructionIndex(llvm::prior(MBBI)).getDefIndex(); + LIS->getInstructionIndex(std::prev(MBBI)).getRegSlot(); // Handle consecutive DBG_VALUE instructions with the same slot index. do { if (handleDebugValue(MBBI, Idx)) { @@ -435,62 +534,49 @@ bool LDVImpl::collectDebugValues(MachineFunction &mf) { return Changed; } -void UserValue::extendDef(SlotIndex Idx, unsigned LocNo, - LiveInterval *LI, const VNInfo *VNI, - SmallVectorImpl *Kills, - LiveIntervals &LIS, MachineDominatorTree &MDT) { - SmallVector Todo; - Todo.push_back(Idx); - - do { - SlotIndex Start = Todo.pop_back_val(); - MachineBasicBlock *MBB = LIS.getMBBFromIndex(Start); - SlotIndex Stop = LIS.getMBBEndIdx(MBB); - LocMap::iterator I = locInts.find(Start); - - // Limit to VNI's live range. - bool ToEnd = true; - if (LI && VNI) { - LiveRange *Range = LI->getLiveRangeContaining(Start); - if (!Range || Range->valno != VNI) { - if (Kills) - Kills->push_back(Start); - continue; - } - if (Range->end < Stop) - Stop = Range->end, ToEnd = false; - } - - // There could already be a short def at Start. - if (I.valid() && I.start() <= Start) { - // Stop when meeting a different location or an already extended interval. - Start = Start.getNextSlot(); - if (I.value() != LocNo || I.stop() != Start) - continue; - // This is a one-slot placeholder. Just skip it. - ++I; +/// We only propagate DBG_VALUES locally here. LiveDebugValues performs a +/// data-flow analysis to propagate them beyond basic block boundaries. +void UserValue::extendDef(SlotIndex Idx, unsigned LocNo, LiveRange *LR, + const VNInfo *VNI, SmallVectorImpl *Kills, + LiveIntervals &LIS, MachineDominatorTree &MDT, + UserValueScopes &UVS) { + SlotIndex Start = Idx; + MachineBasicBlock *MBB = LIS.getMBBFromIndex(Start); + SlotIndex Stop = LIS.getMBBEndIdx(MBB); + LocMap::iterator I = locInts.find(Start); + + // Limit to VNI's live range. + bool ToEnd = true; + if (LR && VNI) { + LiveInterval::Segment *Segment = LR->getSegmentContaining(Start); + if (!Segment || Segment->valno != VNI) { + if (Kills) + Kills->push_back(Start); + return; } + if (Segment->end < Stop) + Stop = Segment->end, ToEnd = false; + } - // Limited by the next def. - if (I.valid() && I.start() < Stop) - Stop = I.start(), ToEnd = false; - // Limited by VNI's live range. - else if (!ToEnd && Kills) - Kills->push_back(Stop); + // There could already be a short def at Start. + if (I.valid() && I.start() <= Start) { + // Stop when meeting a different location or an already extended interval. + Start = Start.getNextSlot(); + if (I.value() != LocNo || I.stop() != Start) + return; + // This is a one-slot placeholder. Just skip it. + ++I; + } - if (Start >= Stop) - continue; + // Limited by the next def. + if (I.valid() && I.start() < Stop) + Stop = I.start(), ToEnd = false; + // Limited by VNI's live range. + else if (!ToEnd && Kills) + Kills->push_back(Stop); + if (Start < Stop) I.insert(Start, Stop, LocNo); - - // If we extended to the MBB end, propagate down the dominator tree. - if (!ToEnd) - continue; - const std::vector &Children = - MDT.getNode(MBB)->getChildren(); - for (unsigned i = 0, e = Children.size(); i != e; ++i) - Todo.push_back(LIS.getMBBStartIdx(Children[i]->getBlock())); - } while (!Todo.empty()); } void @@ -506,27 +592,32 @@ UserValue::addDefsFromCopies(LiveInterval *LI, unsigned LocNo, // Collect all the (vreg, valno) pairs that are copies of LI. SmallVector, 8> CopyValues; - for (MachineRegisterInfo::use_nodbg_iterator - UI = MRI.use_nodbg_begin(LI->reg), - UE = MRI.use_nodbg_end(); UI != UE; ++UI) { + for (MachineOperand &MO : MRI.use_nodbg_operands(LI->reg)) { + MachineInstr *MI = MO.getParent(); // Copies of the full value. - if (UI.getOperand().getSubReg() || !UI->isCopy()) + if (MO.getSubReg() || !MI->isCopy()) continue; - MachineInstr *MI = &*UI; unsigned DstReg = MI->getOperand(0).getReg(); + // Don't follow copies to physregs. These are usually setting up call + // arguments, and the argument registers are always call clobbered. We are + // better off in the source register which could be a callee-saved register, + // or it could be spilled. + if (!TargetRegisterInfo::isVirtualRegister(DstReg)) + continue; + // Is LocNo extended to reach this copy? If not, another def may be blocking // it, or we are looking at a wrong value of LI. SlotIndex Idx = LIS.getInstructionIndex(MI); - LocMap::iterator I = locInts.find(Idx.getUseIndex()); + LocMap::iterator I = locInts.find(Idx.getRegSlot(true)); if (!I.valid() || I.value() != LocNo) continue; if (!LIS.hasInterval(DstReg)) continue; LiveInterval *DstLI = &LIS.getInterval(DstReg); - const VNInfo *DstVNI = DstLI->getVNInfoAt(Idx.getDefIndex()); - assert(DstVNI && DstVNI->def == Idx.getDefIndex() && "Bad copy value"); + const VNInfo *DstVNI = DstLI->getVNInfoAt(Idx.getRegSlot()); + assert(DstVNI && DstVNI->def == Idx.getRegSlot() && "Bad copy value"); CopyValues.push_back(std::make_pair(DstLI, DstVNI)); } @@ -561,8 +652,10 @@ UserValue::addDefsFromCopies(LiveInterval *LI, unsigned LocNo, void UserValue::computeIntervals(MachineRegisterInfo &MRI, + const TargetRegisterInfo &TRI, LiveIntervals &LIS, - MachineDominatorTree &MDT) { + MachineDominatorTree &MDT, + UserValueScopes &UVS) { SmallVector, 16> Defs; // Collect all defs to be extended (Skipping undefs). @@ -576,15 +669,32 @@ UserValue::computeIntervals(MachineRegisterInfo &MRI, unsigned LocNo = Defs[i].second; const MachineOperand &Loc = locations[LocNo]; + if (!Loc.isReg()) { + extendDef(Idx, LocNo, nullptr, nullptr, nullptr, LIS, MDT, UVS); + continue; + } + // Register locations are constrained to where the register value is live. - if (Loc.isReg() && LIS.hasInterval(Loc.getReg())) { - LiveInterval *LI = &LIS.getInterval(Loc.getReg()); - const VNInfo *VNI = LI->getVNInfoAt(Idx); + if (TargetRegisterInfo::isVirtualRegister(Loc.getReg())) { + LiveInterval *LI = nullptr; + const VNInfo *VNI = nullptr; + if (LIS.hasInterval(Loc.getReg())) { + LI = &LIS.getInterval(Loc.getReg()); + VNI = LI->getVNInfoAt(Idx); + } SmallVector Kills; - extendDef(Idx, LocNo, LI, VNI, &Kills, LIS, MDT); - addDefsFromCopies(LI, LocNo, Kills, Defs, MRI, LIS); - } else - extendDef(Idx, LocNo, 0, 0, 0, LIS, MDT); + extendDef(Idx, LocNo, LI, VNI, &Kills, LIS, MDT, UVS); + if (LI) + addDefsFromCopies(LI, LocNo, Kills, Defs, MRI, LIS); + continue; + } + + // For physregs, use the live range of the first regunit as a guide. + unsigned Unit = *MCRegUnitIterator(Loc.getReg(), &TRI); + LiveRange *LR = &LIS.getRegUnit(Unit); + const VNInfo *VNI = LR->getVNInfoAt(Idx); + // Don't track copies from physregs, it is too expensive. + extendDef(Idx, LocNo, LR, VNI, nullptr, LIS, MDT, UVS); } // Finally, erase all the undefs. @@ -597,30 +707,48 @@ UserValue::computeIntervals(MachineRegisterInfo &MRI, void LDVImpl::computeIntervals() { for (unsigned i = 0, e = userValues.size(); i != e; ++i) { - userValues[i]->computeIntervals(MF->getRegInfo(), *LIS, *MDT); + UserValueScopes UVS(userValues[i]->getDebugLoc(), LS); + userValues[i]->computeIntervals(MF->getRegInfo(), *TRI, *LIS, *MDT, UVS); userValues[i]->mapVirtRegs(this); } } bool LDVImpl::runOnMachineFunction(MachineFunction &mf) { + clear(); MF = &mf; LIS = &pass.getAnalysis(); MDT = &pass.getAnalysis(); - TRI = mf.getTarget().getRegisterInfo(); - clear(); + TRI = mf.getSubtarget().getRegisterInfo(); + LS.initialize(mf); DEBUG(dbgs() << "********** COMPUTING LIVE DEBUG VARIABLES: " - << ((Value*)mf.getFunction())->getName() - << " **********\n"); + << mf.getName() << " **********\n"); bool Changed = collectDebugValues(mf); computeIntervals(); DEBUG(print(dbgs())); + ModifiedMF = Changed; return Changed; } +static void removeDebugValues(MachineFunction &mf) { + for (MachineBasicBlock &MBB : mf) { + for (auto MBBI = MBB.begin(), MBBE = MBB.end(); MBBI != MBBE; ) { + if (!MBBI->isDebugValue()) { + ++MBBI; + continue; + } + MBBI = MBB.erase(MBBI); + } + } +} + bool LiveDebugVariables::runOnMachineFunction(MachineFunction &mf) { if (!EnableLDV) return false; + if (!mf.getFunction()->getSubprogram()) { + removeDebugValues(mf); + return false; + } if (!pImpl) pImpl = new LDVImpl(this); return static_cast(pImpl)->runOnMachineFunction(mf); @@ -636,42 +764,143 @@ LiveDebugVariables::~LiveDebugVariables() { delete static_cast(pImpl); } -void UserValue:: -renameRegister(unsigned OldReg, unsigned NewReg, unsigned SubIdx, - const TargetRegisterInfo *TRI) { - for (unsigned i = locations.size(); i; --i) { - unsigned LocNo = i - 1; - MachineOperand &Loc = locations[LocNo]; - if (!Loc.isReg() || Loc.getReg() != OldReg) +//===----------------------------------------------------------------------===// +// Live Range Splitting +//===----------------------------------------------------------------------===// + +bool +UserValue::splitLocation(unsigned OldLocNo, ArrayRef NewRegs, + LiveIntervals& LIS) { + DEBUG({ + dbgs() << "Splitting Loc" << OldLocNo << '\t'; + print(dbgs(), nullptr); + }); + bool DidChange = false; + LocMap::iterator LocMapI; + LocMapI.setMap(locInts); + for (unsigned i = 0; i != NewRegs.size(); ++i) { + LiveInterval *LI = &LIS.getInterval(NewRegs[i]); + if (LI->empty()) continue; - if (TargetRegisterInfo::isPhysicalRegister(NewReg)) - Loc.substPhysReg(NewReg, *TRI); - else - Loc.substVirtReg(NewReg, SubIdx, *TRI); - coalesceLocation(LocNo); + + // Don't allocate the new LocNo until it is needed. + unsigned NewLocNo = ~0u; + + // Iterate over the overlaps between locInts and LI. + LocMapI.find(LI->beginIndex()); + if (!LocMapI.valid()) + continue; + LiveInterval::iterator LII = LI->advanceTo(LI->begin(), LocMapI.start()); + LiveInterval::iterator LIE = LI->end(); + while (LocMapI.valid() && LII != LIE) { + // At this point, we know that LocMapI.stop() > LII->start. + LII = LI->advanceTo(LII, LocMapI.start()); + if (LII == LIE) + break; + + // Now LII->end > LocMapI.start(). Do we have an overlap? + if (LocMapI.value() == OldLocNo && LII->start < LocMapI.stop()) { + // Overlapping correct location. Allocate NewLocNo now. + if (NewLocNo == ~0u) { + MachineOperand MO = MachineOperand::CreateReg(LI->reg, false); + MO.setSubReg(locations[OldLocNo].getSubReg()); + NewLocNo = getLocationNo(MO); + DidChange = true; + } + + SlotIndex LStart = LocMapI.start(); + SlotIndex LStop = LocMapI.stop(); + + // Trim LocMapI down to the LII overlap. + if (LStart < LII->start) + LocMapI.setStartUnchecked(LII->start); + if (LStop > LII->end) + LocMapI.setStopUnchecked(LII->end); + + // Change the value in the overlap. This may trigger coalescing. + LocMapI.setValue(NewLocNo); + + // Re-insert any removed OldLocNo ranges. + if (LStart < LocMapI.start()) { + LocMapI.insert(LStart, LocMapI.start(), OldLocNo); + ++LocMapI; + assert(LocMapI.valid() && "Unexpected coalescing"); + } + if (LStop > LocMapI.stop()) { + ++LocMapI; + LocMapI.insert(LII->end, LStop, OldLocNo); + --LocMapI; + } + } + + // Advance to the next overlap. + if (LII->end < LocMapI.stop()) { + if (++LII == LIE) + break; + LocMapI.advanceTo(LII->start); + } else { + ++LocMapI; + if (!LocMapI.valid()) + break; + LII = LI->advanceTo(LII, LocMapI.start()); + } + } + } + + // Finally, remove any remaining OldLocNo intervals and OldLocNo itself. + locations.erase(locations.begin() + OldLocNo); + LocMapI.goToBegin(); + while (LocMapI.valid()) { + unsigned v = LocMapI.value(); + if (v == OldLocNo) { + DEBUG(dbgs() << "Erasing [" << LocMapI.start() << ';' + << LocMapI.stop() << ")\n"); + LocMapI.erase(); + } else { + if (v > OldLocNo) + LocMapI.setValueUnchecked(v-1); + ++LocMapI; + } } + + DEBUG({dbgs() << "Split result: \t"; print(dbgs(), nullptr);}); + return DidChange; } -void LDVImpl:: -renameRegister(unsigned OldReg, unsigned NewReg, unsigned SubIdx) { - UserValue *UV = lookupVirtReg(OldReg); - if (!UV) - return; +bool +UserValue::splitRegister(unsigned OldReg, ArrayRef NewRegs, + LiveIntervals &LIS) { + bool DidChange = false; + // Split locations referring to OldReg. Iterate backwards so splitLocation can + // safely erase unused locations. + for (unsigned i = locations.size(); i ; --i) { + unsigned LocNo = i-1; + const MachineOperand *Loc = &locations[LocNo]; + if (!Loc->isReg() || Loc->getReg() != OldReg) + continue; + DidChange |= splitLocation(LocNo, NewRegs, LIS); + } + return DidChange; +} - if (TargetRegisterInfo::isVirtualRegister(NewReg)) - mapVirtReg(NewReg, UV); - virtRegToEqClass.erase(OldReg); +void LDVImpl::splitRegister(unsigned OldReg, ArrayRef NewRegs) { + bool DidChange = false; + for (UserValue *UV = lookupVirtReg(OldReg); UV; UV = UV->getNext()) + DidChange |= UV->splitRegister(OldReg, NewRegs, *LIS); - do { - UV->renameRegister(OldReg, NewReg, SubIdx, TRI); - UV = UV->getNext(); - } while (UV); + if (!DidChange) + return; + + // Map all of the new virtual registers. + UserValue *UV = lookupVirtReg(OldReg); + for (unsigned i = 0; i != NewRegs.size(); ++i) + mapVirtReg(NewRegs[i], UV); } void LiveDebugVariables:: -renameRegister(unsigned OldReg, unsigned NewReg, unsigned SubIdx) { +splitRegister(unsigned OldReg, ArrayRef NewRegs, LiveIntervals &LIS) { if (pImpl) - static_cast(pImpl)->renameRegister(OldReg, NewReg, SubIdx); + static_cast(pImpl)->splitRegister(OldReg, NewRegs); } void @@ -687,9 +916,11 @@ UserValue::rewriteLocations(VirtRegMap &VRM, const TargetRegisterInfo &TRI) { unsigned VirtReg = Loc.getReg(); if (VRM.isAssignedReg(VirtReg) && TargetRegisterInfo::isPhysicalRegister(VRM.getPhys(VirtReg))) { + // This can create a %noreg operand in rare cases when the sub-register + // index is no longer available. That means the user value is in a + // non-existent sub-register, and %noreg is exactly what we want. Loc.substPhysReg(VRM.getPhys(VirtReg), TRI); - } else if (VRM.getStackSlot(VirtReg) != VirtRegMap::NO_STACK_SLOT && - VRM.isSpillSlotUsed(VRM.getStackSlot(VirtReg))) { + } else if (VRM.getStackSlot(VirtReg) != VirtRegMap::NO_STACK_SLOT) { // FIXME: Translate SubIdx to a stackslot offset. Loc = MachineOperand::CreateFI(VRM.getStackSlot(VirtReg)); } else { @@ -698,7 +929,6 @@ UserValue::rewriteLocations(VirtRegMap &VRM, const TargetRegisterInfo &TRI) { } coalesceLocation(LocNo); } - DEBUG(print(dbgs(), &TRI)); } /// findInsertLocation - Find an iterator for inserting a DBG_VALUE @@ -721,42 +951,30 @@ findInsertLocation(MachineBasicBlock *MBB, SlotIndex Idx, } // Don't insert anything after the first terminator, though. - return MI->getDesc().isTerminator() ? MBB->getFirstTerminator() : - llvm::next(MachineBasicBlock::iterator(MI)); + return MI->isTerminator() ? MBB->getFirstTerminator() : + std::next(MachineBasicBlock::iterator(MI)); } -DebugLoc UserValue::findDebugLoc() { - DebugLoc D = dl; - dl = DebugLoc(); - return D; -} void UserValue::insertDebugValue(MachineBasicBlock *MBB, SlotIndex Idx, unsigned LocNo, LiveIntervals &LIS, const TargetInstrInfo &TII) { MachineBasicBlock::iterator I = findInsertLocation(MBB, Idx, LIS); MachineOperand &Loc = locations[LocNo]; - - // Frame index locations may require a target callback. - if (Loc.isFI()) { - MachineInstr *MI = TII.emitFrameIndexDebugValue(*MBB->getParent(), - Loc.getIndex(), offset, variable, - findDebugLoc()); - if (MI) { - MBB->insert(I, MI); - return; - } - } - // This is not a frame index, or the target is happy with a standard FI. - BuildMI(*MBB, I, findDebugLoc(), TII.get(TargetOpcode::DBG_VALUE)) - .addOperand(Loc).addImm(offset).addMetadata(variable); -} - -void UserValue::insertDebugKill(MachineBasicBlock *MBB, SlotIndex Idx, - LiveIntervals &LIS, const TargetInstrInfo &TII) { - MachineBasicBlock::iterator I = findInsertLocation(MBB, Idx, LIS); - BuildMI(*MBB, I, findDebugLoc(), TII.get(TargetOpcode::DBG_VALUE)).addReg(0) - .addImm(offset).addMetadata(variable); + ++NumInsertedDebugValues; + + assert(cast(Variable) + ->isValidLocationForIntrinsic(getDebugLoc()) && + "Expected inlined-at fields to agree"); + if (Loc.isReg()) + BuildMI(*MBB, I, getDebugLoc(), TII.get(TargetOpcode::DBG_VALUE), + IsIndirect, Loc.getReg(), offset, Variable, Expression); + else + BuildMI(*MBB, I, getDebugLoc(), TII.get(TargetOpcode::DBG_VALUE)) + .addOperand(Loc) + .addImm(offset) + .addMetadata(Variable) + .addMetadata(Expression); } void UserValue::emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS, @@ -768,12 +986,11 @@ void UserValue::emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS, SlotIndex Stop = I.stop(); unsigned LocNo = I.value(); DEBUG(dbgs() << "\t[" << Start << ';' << Stop << "):" << LocNo); - MachineFunction::iterator MBB = LIS.getMBBFromIndex(Start); - SlotIndex MBBEnd = LIS.getMBBEndIdx(MBB); + MachineFunction::iterator MBB = LIS.getMBBFromIndex(Start)->getIterator(); + SlotIndex MBBEnd = LIS.getMBBEndIdx(&*MBB); DEBUG(dbgs() << " BB#" << MBB->getNumber() << '-' << MBBEnd); - insertDebugValue(MBB, Start, LocNo, LIS, TII); - + insertDebugValue(&*MBB, Start, LocNo, LIS, TII); // This interval may span multiple basic blocks. // Insert a DBG_VALUE into each one. while(Stop > MBBEnd) { @@ -781,31 +998,29 @@ void UserValue::emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS, Start = MBBEnd; if (++MBB == MFEnd) break; - MBBEnd = LIS.getMBBEndIdx(MBB); + MBBEnd = LIS.getMBBEndIdx(&*MBB); DEBUG(dbgs() << " BB#" << MBB->getNumber() << '-' << MBBEnd); - insertDebugValue(MBB, Start, LocNo, LIS, TII); + insertDebugValue(&*MBB, Start, LocNo, LIS, TII); } DEBUG(dbgs() << '\n'); if (MBB == MFEnd) break; ++I; - if (Stop == MBBEnd) - continue; - // The current interval ends before MBB. - // Insert a kill if there is a gap. - if (!I.valid() || I.start() > Stop) - insertDebugKill(MBB, Stop, LIS, TII); } } void LDVImpl::emitDebugValues(VirtRegMap *VRM) { DEBUG(dbgs() << "********** EMITTING LIVE DEBUG VARIABLES **********\n"); - const TargetInstrInfo *TII = MF->getTarget().getInstrInfo(); + if (!MF) + return; + const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo(); for (unsigned i = 0, e = userValues.size(); i != e; ++i) { + DEBUG(userValues[i]->print(dbgs(), TRI)); userValues[i]->rewriteLocations(*VRM, *TRI); userValues[i]->emitDebugValues(VRM, *LIS, *TII); } + EmitDone = true; } void LiveDebugVariables::emitDebugValues(VirtRegMap *VRM) { @@ -813,6 +1028,9 @@ void LiveDebugVariables::emitDebugValues(VirtRegMap *VRM) { static_cast(pImpl)->emitDebugValues(VRM); } +bool LiveDebugVariables::doInitialization(Module &M) { + return Pass::doInitialization(M); +} #ifndef NDEBUG void LiveDebugVariables::dump() { @@ -820,4 +1038,3 @@ void LiveDebugVariables::dump() { static_cast(pImpl)->print(dbgs()); } #endif -