X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FLiveDebugVariables.cpp;h=defc1279ec8c8db61b0736dd65b5855ced581c2c;hb=b21d9aebba7e45ddcbce61dd501000049cefb335;hp=292928f8e787290498ca4c43b8634a1a4b4e5288;hpb=cf724f078623e786fc92335fdb0ec70b46f2e86d;p=oota-llvm.git diff --git a/lib/CodeGen/LiveDebugVariables.cpp b/lib/CodeGen/LiveDebugVariables.cpp index 292928f8e78..defc1279ec8 100644 --- a/lib/CodeGen/LiveDebugVariables.cpp +++ b/lib/CodeGen/LiveDebugVariables.cpp @@ -23,9 +23,12 @@ #include "LiveDebugVariables.h" #include "VirtRegMap.h" #include "llvm/Constants.h" +#include "llvm/DebugInfo.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" @@ -44,6 +47,7 @@ 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", @@ -67,6 +71,29 @@ LiveDebugVariables::LiveDebugVariables() : MachineFunctionPass(ID), pImpl(0) { /// LocMap - Map of where a user value is live, and its location. typedef IntervalMap LocMap; +namespace { +/// UserValueScopes - Keeps track of lexical scopes associated with an +/// 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); + if (LBlocks.count(MBB) != 0 || LS.dominates(DL, MBB)) + return true; + return false; + } +}; +} // 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 @@ -123,7 +150,7 @@ public: /// getNext - Return the next UserValue in the equivalence class. UserValue *getNext() const { return next; } - /// match - Does this UserValue match the aprameters? + /// match - Does this UserValue match the parameters? bool match(const MDNode *Var, unsigned Offset) const { return Var == variable && Offset == offset; } @@ -179,6 +206,9 @@ 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 @@ -195,7 +225,8 @@ public: void extendDef(SlotIndex Idx, unsigned LocNo, LiveInterval *LI, 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 @@ -212,8 +243,9 @@ 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, @@ -236,6 +268,9 @@ public: /// Only first one needs DebugLoc to identify variable's lexical scope /// in source file. DebugLoc findDebugLoc(); + + /// getDebugLoc - Return DebugLoc of this UserValue. + DebugLoc getDebugLoc() { return dl;} void print(raw_ostream&, const TargetMachine*); }; } // namespace @@ -247,6 +282,7 @@ class LDVImpl { LocMap::Allocator allocator; MachineFunction *MF; LiveIntervals *LIS; + LexicalScopes LS; MachineDominatorTree *MDT; const TargetRegisterInfo *TRI; @@ -312,8 +348,10 @@ public: } // namespace void UserValue::print(raw_ostream &OS, const TargetMachine *TM) { - if (const MDString *MDS = dyn_cast(variable->getOperand(2))) - OS << "!\"" << MDS->getString() << "\"\t"; + DIVariable DV(variable); + OS << "!\""; + DV.printExtendedName(OS); + OS << "\"\t"; if (offset) OS << '+' << offset; for (LocMap::const_iterator I = locInts.begin(); I.valid(); ++I) { @@ -430,7 +468,7 @@ 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(llvm::prior(MBBI)).getRegSlot(); // Handle consecutive DBG_VALUE instructions with the same slot index. do { if (handleDebugValue(MBBI, Idx)) { @@ -447,10 +485,10 @@ bool LDVImpl::collectDebugValues(MachineFunction &mf) { void UserValue::extendDef(SlotIndex Idx, unsigned LocNo, LiveInterval *LI, const VNInfo *VNI, SmallVectorImpl *Kills, - LiveIntervals &LIS, MachineDominatorTree &MDT) { + LiveIntervals &LIS, MachineDominatorTree &MDT, + UserValueScopes &UVS) { SmallVector Todo; Todo.push_back(Idx); - do { SlotIndex Start = Todo.pop_back_val(); MachineBasicBlock *MBB = LIS.getMBBFromIndex(Start); @@ -497,8 +535,11 @@ void UserValue::extendDef(SlotIndex Idx, unsigned LocNo, 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())); + for (unsigned i = 0, e = Children.size(); i != e; ++i) { + MachineBasicBlock *MBB = Children[i]->getBlock(); + if (UVS.dominates(MBB)) + Todo.push_back(LIS.getMBBStartIdx(MBB)); + } } while (!Todo.empty()); } @@ -534,15 +575,15 @@ UserValue::addDefsFromCopies(LiveInterval *LI, unsigned LocNo, // 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)); } @@ -577,8 +618,10 @@ 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). @@ -592,15 +635,32 @@ UserValue::computeIntervals(MachineRegisterInfo &MRI, unsigned LocNo = Defs[i].second; const MachineOperand &Loc = locations[LocNo]; + if (!Loc.isReg()) { + extendDef(Idx, LocNo, 0, 0, 0, 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 = 0; + const VNInfo *VNI = 0; + 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); + LiveInterval *LI = &LIS.getRegUnit(Unit); + const VNInfo *VNI = LI->getVNInfoAt(Idx); + // Don't track copies from physregs, it is too expensive. + extendDef(Idx, LocNo, LI, VNI, 0, LIS, MDT, UVS); } // Finally, erase all the undefs. @@ -613,7 +673,8 @@ 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); } } @@ -624,13 +685,14 @@ bool LDVImpl::runOnMachineFunction(MachineFunction &mf) { MDT = &pass.getAnalysis(); TRI = mf.getTarget().getRegisterInfo(); clear(); + 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())); + LS.releaseMemory(); return Changed; } @@ -676,7 +738,8 @@ renameRegister(unsigned OldReg, unsigned NewReg, unsigned SubIdx) { if (TargetRegisterInfo::isVirtualRegister(NewReg)) mapVirtReg(NewReg, UV); - virtRegToEqClass.erase(OldReg); + if (OldReg != NewReg) + virtRegToEqClass.erase(OldReg); do { UV->renameRegister(OldReg, NewReg, SubIdx, TRI); @@ -796,7 +859,7 @@ bool UserValue::splitRegister(unsigned OldReg, ArrayRef NewRegs) { bool DidChange = false; // Split locations referring to OldReg. Iterate backwards so splitLocation can - // safely erase unuused locations. + // safely erase unused locations. for (unsigned i = locations.size(); i ; --i) { unsigned LocNo = i-1; const MachineOperand *Loc = &locations[LocNo]; @@ -844,8 +907,7 @@ UserValue::rewriteLocations(VirtRegMap &VRM, const TargetRegisterInfo &TRI) { // 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 { @@ -876,8 +938,8 @@ 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() : + llvm::next(MachineBasicBlock::iterator(MI)); } DebugLoc UserValue::findDebugLoc() { @@ -891,6 +953,7 @@ void UserValue::insertDebugValue(MachineBasicBlock *MBB, SlotIndex Idx, const TargetInstrInfo &TII) { MachineBasicBlock::iterator I = findInsertLocation(MBB, Idx, LIS); MachineOperand &Loc = locations[LocNo]; + ++NumInsertedDebugValues; // Frame index locations may require a target callback. if (Loc.isFI()) { @@ -921,7 +984,6 @@ void UserValue::emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS, DEBUG(dbgs() << " BB#" << MBB->getNumber() << '-' << MBBEnd); insertDebugValue(MBB, Start, LocNo, LIS, TII); - // This interval may span multiple basic blocks. // Insert a DBG_VALUE into each one. while(Stop > MBBEnd) {