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diff --git a/contrib/llvm/lib/CodeGen/LiveDebugVariables.cpp b/contrib/llvm/lib/CodeGen/LiveDebugVariables.cpp
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+//===- LiveDebugVariables.cpp - Tracking debug info variables -------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the LiveDebugVariables analysis.
+//
+// Remove all DBG_VALUE instructions referencing virtual registers and replace
+// them with a data structure tracking where live user variables are kept - in a
+// virtual register or in a stack slot.
+//
+// Allow the data structure to be updated during register allocation when values
+// are moved between registers and stack slots. Finally emit new DBG_VALUE
+// instructions after register allocation is complete.
+//
+//===----------------------------------------------------------------------===//
+
+#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/CodeGen/LiveIntervalAnalysis.h"
+#include "llvm/CodeGen/MachineDominators.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+
+using namespace llvm;
+
+static cl::opt<bool>
+EnableLDV("live-debug-variables", cl::init(true),
+ cl::desc("Enable the live debug variables pass"), cl::Hidden);
+
+char LiveDebugVariables::ID = 0;
+
+INITIALIZE_PASS_BEGIN(LiveDebugVariables, "livedebugvars",
+ "Debug Variable Analysis", false, false)
+INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
+INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
+INITIALIZE_PASS_END(LiveDebugVariables, "livedebugvars",
+ "Debug Variable Analysis", false, false)
+
+void LiveDebugVariables::getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.addRequired<MachineDominatorTree>();
+ AU.addRequiredTransitive<LiveIntervals>();
+ AU.setPreservesAll();
+ MachineFunctionPass::getAnalysisUsage(AU);
+}
+
+LiveDebugVariables::LiveDebugVariables() : MachineFunctionPass(ID), pImpl(0) {
+ initializeLiveDebugVariablesPass(*PassRegistry::getPassRegistry());
+}
+
+/// LocMap - Map of where a user value is live, and its location.
+typedef IntervalMap<SlotIndex, unsigned, 4> LocMap;
+
+/// 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
+/// holds part of a user variable. The part is identified by a byte offset.
+///
+/// UserValues are grouped into equivalence classes for easier searching. Two
+/// user values are related if they refer to the same variable, or if they are
+/// held by the same virtual register. The equivalence class is the transitive
+/// closure of that relation.
+namespace {
+class UserValue {
+ const MDNode *variable; ///< The debug info variable we are part of.
+ unsigned offset; ///< Byte offset into variable.
+ DebugLoc dl; ///< The debug location for the variable. This is
+ ///< used by dwarf writer to find lexical scope.
+ UserValue *leader; ///< Equivalence class leader.
+ UserValue *next; ///< Next value in equivalence class, or null.
+
+ /// Numbered locations referenced by locmap.
+ SmallVector<MachineOperand, 4> locations;
+
+ /// Map of slot indices where this value is live.
+ LocMap locInts;
+
+ /// coalesceLocation - After LocNo was changed, check if it has become
+ /// identical to another location, and coalesce them. This may cause LocNo or
+ /// a later location to be erased, but no earlier location will be erased.
+ void coalesceLocation(unsigned LocNo);
+
+ /// insertDebugValue - Insert a DBG_VALUE into MBB at Idx for LocNo.
+ 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);
+
+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)
+ {}
+
+ /// getLeader - Get the leader of this value's equivalence class.
+ UserValue *getLeader() {
+ UserValue *l = leader;
+ while (l != l->leader)
+ l = l->leader;
+ return leader = l;
+ }
+
+ /// 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;
+ }
+
+ /// merge - Merge equivalence classes.
+ static UserValue *merge(UserValue *L1, UserValue *L2) {
+ L2 = L2->getLeader();
+ if (!L1)
+ return L2;
+ L1 = L1->getLeader();
+ if (L1 == L2)
+ return L1;
+ // Splice L2 before L1's members.
+ UserValue *End = L2;
+ while (End->next)
+ End->leader = L1, End = End->next;
+ End->leader = L1;
+ End->next = L1->next;
+ L1->next = L2;
+ return L1;
+ }
+
+ /// getLocationNo - Return the location number that matches Loc.
+ unsigned getLocationNo(const MachineOperand &LocMO) {
+ if (LocMO.isReg() && LocMO.getReg() == 0)
+ return ~0u;
+ for (unsigned i = 0, e = locations.size(); i != e; ++i)
+ if (LocMO.isIdenticalTo(locations[i]))
+ return i;
+ locations.push_back(LocMO);
+ // We are storing a MachineOperand outside a MachineInstr.
+ locations.back().clearParent();
+ return locations.size() - 1;
+ }
+
+ /// addDef - Add a definition point to this value.
+ void addDef(SlotIndex Idx, const MachineOperand &LocMO) {
+ // Add a singular (Idx,Idx) -> Loc mapping.
+ LocMap::iterator I = locInts.find(Idx);
+ if (!I.valid() || I.start() != Idx)
+ I.insert(Idx, Idx.getNextSlot(), getLocationNo(LocMO));
+ }
+
+ /// extendDef - Extend the current definition as far as possible down the
+ /// dominator tree. Stop when meeting an existing def or when leaving the live
+ /// range of VNI.
+ /// @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 LIS Live intervals analysis.
+ /// @param MDT Dominator tree.
+ void extendDef(SlotIndex Idx, unsigned LocNo,
+ LiveInterval *LI, const VNInfo *VNI,
+ LiveIntervals &LIS, MachineDominatorTree &MDT);
+
+ /// computeIntervals - Compute the live intervals of all locations after
+ /// collecting all their def points.
+ void computeIntervals(LiveIntervals &LIS, MachineDominatorTree &MDT);
+
+ /// renameRegister - Update locations to rewrite OldReg as NewReg:SubIdx.
+ void renameRegister(unsigned OldReg, unsigned NewReg, unsigned SubIdx,
+ const TargetRegisterInfo *TRI);
+
+ /// 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.
+ 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*);
+};
+} // namespace
+
+/// LDVImpl - Implementation of the LiveDebugVariables pass.
+namespace {
+class LDVImpl {
+ LiveDebugVariables &pass;
+ LocMap::Allocator allocator;
+ MachineFunction *MF;
+ LiveIntervals *LIS;
+ MachineDominatorTree *MDT;
+ const TargetRegisterInfo *TRI;
+
+ /// userValues - All allocated UserValue instances.
+ SmallVector<UserValue*, 8> userValues;
+
+ /// Map virtual register to eq class leader.
+ typedef DenseMap<unsigned, UserValue*> VRMap;
+ VRMap virtRegToEqClass;
+
+ /// Map user variable to eq class leader.
+ typedef DenseMap<const MDNode *, UserValue*> UVMap;
+ UVMap userVarMap;
+
+ /// getUserValue - Find or create a UserValue.
+ UserValue *getUserValue(const MDNode *Var, unsigned Offset, DebugLoc DL);
+
+ /// lookupVirtReg - Find the EC leader for VirtReg or null.
+ UserValue *lookupVirtReg(unsigned VirtReg);
+
+ /// mapVirtReg - Map virtual register to an equivalence class.
+ void mapVirtReg(unsigned VirtReg, UserValue *EC);
+
+ /// handleDebugValue - Add DBG_VALUE instruction to our maps.
+ /// @param MI DBG_VALUE instruction
+ /// @param Idx Last valid SLotIndex before instruction.
+ /// @return True if the DBG_VALUE instruction should be deleted.
+ bool handleDebugValue(MachineInstr *MI, SlotIndex Idx);
+
+ /// collectDebugValues - Collect and erase all DBG_VALUE instructions, adding
+ /// a UserValue def for each instruction.
+ /// @param mf MachineFunction to be scanned.
+ /// @return True if any debug values were found.
+ bool collectDebugValues(MachineFunction &mf);
+
+ /// computeIntervals - Compute the live intervals of all user values after
+ /// collecting all their def points.
+ void computeIntervals();
+
+public:
+ LDVImpl(LiveDebugVariables *ps) : pass(*ps) {}
+ bool runOnMachineFunction(MachineFunction &mf);
+
+ /// clear - Relase all memory.
+ void clear() {
+ DeleteContainerPointers(userValues);
+ userValues.clear();
+ virtRegToEqClass.clear();
+ userVarMap.clear();
+ }
+
+ /// renameRegister - Replace all references to OldReg wiht NewReg:SubIdx.
+ void renameRegister(unsigned OldReg, unsigned NewReg, unsigned SubIdx);
+
+ /// emitDebugVariables - Recreate DBG_VALUE instruction from data structures.
+ void emitDebugValues(VirtRegMap *VRM);
+
+ void print(raw_ostream&);
+};
+} // namespace
+
+void UserValue::print(raw_ostream &OS, const TargetRegisterInfo *TRI) {
+ if (const MDString *MDS = dyn_cast<MDString>(variable->getOperand(2)))
+ OS << "!\"" << MDS->getString() << "\"\t";
+ if (offset)
+ OS << '+' << offset;
+ for (LocMap::const_iterator I = locInts.begin(); I.valid(); ++I) {
+ OS << " [" << I.start() << ';' << I.stop() << "):";
+ if (I.value() == ~0u)
+ OS << "undef";
+ else
+ OS << I.value();
+ }
+ for (unsigned i = 0, e = locations.size(); i != e; ++i)
+ OS << " Loc" << i << '=' << locations[i];
+ OS << '\n';
+}
+
+void LDVImpl::print(raw_ostream &OS) {
+ OS << "********** DEBUG VARIABLES **********\n";
+ for (unsigned i = 0, e = userValues.size(); i != e; ++i)
+ userValues[i]->print(OS, TRI);
+}
+
+void UserValue::coalesceLocation(unsigned LocNo) {
+ unsigned KeepLoc = 0;
+ for (unsigned e = locations.size(); KeepLoc != e; ++KeepLoc) {
+ if (KeepLoc == LocNo)
+ continue;
+ if (locations[KeepLoc].isIdenticalTo(locations[LocNo]))
+ break;
+ }
+ // No matches.
+ if (KeepLoc == locations.size())
+ return;
+
+ // Keep the smaller location, erase the larger one.
+ unsigned EraseLoc = LocNo;
+ if (KeepLoc > EraseLoc)
+ std::swap(KeepLoc, EraseLoc);
+ locations.erase(locations.begin() + EraseLoc);
+
+ // Rewrite values.
+ for (LocMap::iterator I = locInts.begin(); I.valid(); ++I) {
+ unsigned v = I.value();
+ if (v == EraseLoc)
+ I.setValue(KeepLoc); // Coalesce when possible.
+ else if (v > EraseLoc)
+ I.setValueUnchecked(v-1); // Avoid coalescing with untransformed values.
+ }
+}
+
+UserValue *LDVImpl::getUserValue(const MDNode *Var, unsigned Offset,
+ DebugLoc DL) {
+ UserValue *&Leader = userVarMap[Var];
+ if (Leader) {
+ UserValue *UV = Leader->getLeader();
+ Leader = UV;
+ for (; UV; UV = UV->getNext())
+ if (UV->match(Var, Offset))
+ return UV;
+ }
+
+ UserValue *UV = new UserValue(Var, Offset, DL, allocator);
+ userValues.push_back(UV);
+ Leader = UserValue::merge(Leader, UV);
+ return UV;
+}
+
+void LDVImpl::mapVirtReg(unsigned VirtReg, UserValue *EC) {
+ assert(TargetRegisterInfo::isVirtualRegister(VirtReg) && "Only map VirtRegs");
+ UserValue *&Leader = virtRegToEqClass[VirtReg];
+ Leader = UserValue::merge(Leader, EC);
+}
+
+UserValue *LDVImpl::lookupVirtReg(unsigned VirtReg) {
+ if (UserValue *UV = virtRegToEqClass.lookup(VirtReg))
+ return UV->getLeader();
+ return 0;
+}
+
+bool LDVImpl::handleDebugValue(MachineInstr *MI, SlotIndex Idx) {
+ // DBG_VALUE loc, offset, variable
+ if (MI->getNumOperands() != 3 ||
+ !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());
+
+ // If the location is a virtual register, make sure it is mapped.
+ if (MI->getOperand(0).isReg()) {
+ unsigned Reg = MI->getOperand(0).getReg();
+ if (TargetRegisterInfo::isVirtualRegister(Reg))
+ mapVirtReg(Reg, UV);
+ }
+
+ UV->addDef(Idx, MI->getOperand(0));
+ return true;
+}
+
+bool LDVImpl::collectDebugValues(MachineFunction &mf) {
+ bool Changed = false;
+ for (MachineFunction::iterator MFI = mf.begin(), MFE = mf.end(); MFI != MFE;
+ ++MFI) {
+ MachineBasicBlock *MBB = MFI;
+ for (MachineBasicBlock::iterator MBBI = MBB->begin(), MBBE = MBB->end();
+ MBBI != MBBE;) {
+ if (!MBBI->isDebugValue()) {
+ ++MBBI;
+ continue;
+ }
+ // 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();
+ // Handle consecutive DBG_VALUE instructions with the same slot index.
+ do {
+ if (handleDebugValue(MBBI, Idx)) {
+ MBBI = MBB->erase(MBBI);
+ Changed = true;
+ } else
+ ++MBBI;
+ } while (MBBI != MBBE && MBBI->isDebugValue());
+ }
+ }
+ return Changed;
+}
+
+void UserValue::extendDef(SlotIndex Idx, unsigned LocNo,
+ LiveInterval *LI, const VNInfo *VNI,
+ LiveIntervals &LIS, MachineDominatorTree &MDT) {
+ SmallVector<SlotIndex, 16> 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)
+ 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;
+ }
+
+ // Limited by the next def.
+ if (I.valid() && I.start() < Stop)
+ Stop = I.start(), ToEnd = false;
+
+ if (Start >= Stop)
+ continue;
+
+ I.insert(Start, Stop, LocNo);
+
+ // If we extended to the MBB end, propagate down the dominator tree.
+ if (!ToEnd)
+ continue;
+ const std::vector<MachineDomTreeNode*> &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
+UserValue::computeIntervals(LiveIntervals &LIS, MachineDominatorTree &MDT) {
+ SmallVector<std::pair<SlotIndex, unsigned>, 16> Defs;
+
+ // Collect all defs to be extended (Skipping undefs).
+ for (LocMap::const_iterator I = locInts.begin(); I.valid(); ++I)
+ if (I.value() != ~0u)
+ Defs.push_back(std::make_pair(I.start(), I.value()));
+
+ for (unsigned i = 0, e = Defs.size(); i != e; ++i) {
+ SlotIndex Idx = Defs[i].first;
+ unsigned LocNo = Defs[i].second;
+ const MachineOperand &Loc = locations[LocNo];
+
+ // 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);
+ extendDef(Idx, LocNo, LI, VNI, LIS, MDT);
+ } else
+ extendDef(Idx, LocNo, 0, 0, LIS, MDT);
+ }
+
+ // Finally, erase all the undefs.
+ for (LocMap::iterator I = locInts.begin(); I.valid();)
+ if (I.value() == ~0u)
+ I.erase();
+ else
+ ++I;
+}
+
+void LDVImpl::computeIntervals() {
+ for (unsigned i = 0, e = userValues.size(); i != e; ++i)
+ userValues[i]->computeIntervals(*LIS, *MDT);
+}
+
+bool LDVImpl::runOnMachineFunction(MachineFunction &mf) {
+ MF = &mf;
+ LIS = &pass.getAnalysis<LiveIntervals>();
+ MDT = &pass.getAnalysis<MachineDominatorTree>();
+ TRI = mf.getTarget().getRegisterInfo();
+ clear();
+ DEBUG(dbgs() << "********** COMPUTING LIVE DEBUG VARIABLES: "
+ << ((Value*)mf.getFunction())->getName()
+ << " **********\n");
+
+ bool Changed = collectDebugValues(mf);
+ computeIntervals();
+ DEBUG(print(dbgs()));
+ return Changed;
+}
+
+bool LiveDebugVariables::runOnMachineFunction(MachineFunction &mf) {
+ if (!EnableLDV)
+ return false;
+ if (!pImpl)
+ pImpl = new LDVImpl(this);
+ return static_cast<LDVImpl*>(pImpl)->runOnMachineFunction(mf);
+}
+
+void LiveDebugVariables::releaseMemory() {
+ if (pImpl)
+ static_cast<LDVImpl*>(pImpl)->clear();
+}
+
+LiveDebugVariables::~LiveDebugVariables() {
+ if (pImpl)
+ delete static_cast<LDVImpl*>(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)
+ continue;
+ if (TargetRegisterInfo::isPhysicalRegister(NewReg))
+ Loc.substPhysReg(NewReg, *TRI);
+ else
+ Loc.substVirtReg(NewReg, SubIdx, *TRI);
+ coalesceLocation(LocNo);
+ }
+}
+
+void LDVImpl::
+renameRegister(unsigned OldReg, unsigned NewReg, unsigned SubIdx) {
+ UserValue *UV = lookupVirtReg(OldReg);
+ if (!UV)
+ return;
+
+ if (TargetRegisterInfo::isVirtualRegister(NewReg))
+ mapVirtReg(NewReg, UV);
+ virtRegToEqClass.erase(OldReg);
+
+ do {
+ UV->renameRegister(OldReg, NewReg, SubIdx, TRI);
+ UV = UV->getNext();
+ } while (UV);
+}
+
+void LiveDebugVariables::
+renameRegister(unsigned OldReg, unsigned NewReg, unsigned SubIdx) {
+ if (pImpl)
+ static_cast<LDVImpl*>(pImpl)->renameRegister(OldReg, NewReg, SubIdx);
+}
+
+void
+UserValue::rewriteLocations(VirtRegMap &VRM, const TargetRegisterInfo &TRI) {
+ // Iterate over locations in reverse makes it easier to handle coalescing.
+ for (unsigned i = locations.size(); i ; --i) {
+ unsigned LocNo = i-1;
+ MachineOperand &Loc = locations[LocNo];
+ // Only virtual registers are rewritten.
+ if (!Loc.isReg() || !Loc.getReg() ||
+ !TargetRegisterInfo::isVirtualRegister(Loc.getReg()))
+ continue;
+ unsigned VirtReg = Loc.getReg();
+ if (VRM.isAssignedReg(VirtReg) &&
+ TargetRegisterInfo::isPhysicalRegister(VRM.getPhys(VirtReg))) {
+ Loc.substPhysReg(VRM.getPhys(VirtReg), TRI);
+ } else if (VRM.getStackSlot(VirtReg) != VirtRegMap::NO_STACK_SLOT &&
+ VRM.isSpillSlotUsed(VRM.getStackSlot(VirtReg))) {
+ // FIXME: Translate SubIdx to a stackslot offset.
+ Loc = MachineOperand::CreateFI(VRM.getStackSlot(VirtReg));
+ } else {
+ Loc.setReg(0);
+ Loc.setSubReg(0);
+ }
+ coalesceLocation(LocNo);
+ }
+ DEBUG(print(dbgs(), &TRI));
+}
+
+/// findInsertLocation - Find an iterator for inserting a DBG_VALUE
+/// instruction.
+static MachineBasicBlock::iterator
+findInsertLocation(MachineBasicBlock *MBB, SlotIndex Idx,
+ LiveIntervals &LIS) {
+ SlotIndex Start = LIS.getMBBStartIdx(MBB);
+ Idx = Idx.getBaseIndex();
+
+ // Try to find an insert location by going backwards from Idx.
+ MachineInstr *MI;
+ while (!(MI = LIS.getInstructionFromIndex(Idx))) {
+ // We've reached the beginning of MBB.
+ if (Idx == Start) {
+ MachineBasicBlock::iterator I = MBB->SkipPHIsAndLabels(MBB->begin());
+ return I;
+ }
+ Idx = Idx.getPrevIndex();
+ }
+
+ // Don't insert anything after the first terminator, though.
+ return MI->getDesc().isTerminator() ? MBB->getFirstTerminator() :
+ llvm::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);
+}
+
+void UserValue::emitDebugValues(VirtRegMap *VRM, LiveIntervals &LIS,
+ const TargetInstrInfo &TII) {
+ MachineFunction::iterator MFEnd = VRM->getMachineFunction().end();
+
+ for (LocMap::const_iterator I = locInts.begin(); I.valid();) {
+ SlotIndex Start = I.start();
+ 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);
+
+ 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) {
+ // Move to the next block.
+ Start = MBBEnd;
+ if (++MBB == MFEnd)
+ break;
+ MBBEnd = LIS.getMBBEndIdx(MBB);
+ DEBUG(dbgs() << " BB#" << MBB->getNumber() << '-' << MBBEnd);
+ 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();
+ for (unsigned i = 0, e = userValues.size(); i != e; ++i) {
+ userValues[i]->rewriteLocations(*VRM, *TRI);
+ userValues[i]->emitDebugValues(VRM, *LIS, *TII);
+ }
+}
+
+void LiveDebugVariables::emitDebugValues(VirtRegMap *VRM) {
+ if (pImpl)
+ static_cast<LDVImpl*>(pImpl)->emitDebugValues(VRM);
+}
+
+
+#ifndef NDEBUG
+void LiveDebugVariables::dump() {
+ if (pImpl)
+ static_cast<LDVImpl*>(pImpl)->print(dbgs());
+}
+#endif
+
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