Check in LLVM r95781.

15 files changed, 8396 insertions, 0 deletions

diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
new file mode 100644
index 0000000000..fc08384593
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -0,0 +1,1790 @@
+//===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===//
+//
+//                     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 AsmPrinter class.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "asm-printer"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/Assembly/Writer.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Constants.h"
+#include "llvm/Module.h"
+#include "llvm/CodeGen/DwarfWriter.h"
+#include "llvm/CodeGen/GCMetadataPrinter.h"
+#include "llvm/CodeGen/MachineConstantPool.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineJumpTableInfo.h"
+#include "llvm/CodeGen/MachineLoopInfo.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/Analysis/ConstantFolding.h"
+#include "llvm/Analysis/DebugInfo.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/Target/Mangler.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetLoweringObjectFile.h"
+#include "llvm/Target/TargetOptions.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/FormattedStream.h"
+#include <cerrno>
+using namespace llvm;
+
+STATISTIC(EmittedInsts, "Number of machine instrs printed");
+
+char AsmPrinter::ID = 0;
+AsmPrinter::AsmPrinter(formatted_raw_ostream &o, TargetMachine &tm,
+                       MCContext &Ctx, MCStreamer &Streamer,
+                       const MCAsmInfo *T)
+  : MachineFunctionPass(&ID), O(o),
+    TM(tm), MAI(T), TRI(tm.getRegisterInfo()),
+    OutContext(Ctx), OutStreamer(Streamer),
+    LastMI(0), LastFn(0), Counter(~0U), PrevDLT(NULL) {
+  DW = 0; MMI = 0;
+  VerboseAsm = Streamer.isVerboseAsm();
+}
+
+AsmPrinter::~AsmPrinter() {
+  for (gcp_iterator I = GCMetadataPrinters.begin(),
+                    E = GCMetadataPrinters.end(); I != E; ++I)
+    delete I->second;
+  
+  delete &OutStreamer;
+  delete &OutContext;
+}
+
+/// getFunctionNumber - Return a unique ID for the current function.
+///
+unsigned AsmPrinter::getFunctionNumber() const {
+  return MF->getFunctionNumber();
+}
+
+TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
+  return TM.getTargetLowering()->getObjFileLowering();
+}
+
+/// getCurrentSection() - Return the current section we are emitting to.
+const MCSection *AsmPrinter::getCurrentSection() const {
+  return OutStreamer.getCurrentSection();
+}
+
+
+void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+  MachineFunctionPass::getAnalysisUsage(AU);
+  AU.addRequired<GCModuleInfo>();
+  if (VerboseAsm)
+    AU.addRequired<MachineLoopInfo>();
+}
+
+bool AsmPrinter::doInitialization(Module &M) {
+  // Initialize TargetLoweringObjectFile.
+  const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
+    .Initialize(OutContext, TM);
+  
+  Mang = new Mangler(*MAI);
+  
+  // Allow the target to emit any magic that it wants at the start of the file.
+  EmitStartOfAsmFile(M);
+
+  // Very minimal debug info. It is ignored if we emit actual debug info. If we
+  // don't, this at least helps the user find where a global came from.
+  if (MAI->hasSingleParameterDotFile()) {
+    // .file "foo.c"
+    OutStreamer.EmitFileDirective(M.getModuleIdentifier());
+  }
+
+  GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
+  assert(MI && "AsmPrinter didn't require GCModuleInfo?");
+  for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
+    if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
+      MP->beginAssembly(O, *this, *MAI);
+  
+  if (!M.getModuleInlineAsm().empty())
+    O << MAI->getCommentString() << " Start of file scope inline assembly\n"
+      << M.getModuleInlineAsm()
+      << '\n' << MAI->getCommentString()
+      << " End of file scope inline assembly\n";
+
+  MMI = getAnalysisIfAvailable<MachineModuleInfo>();
+  if (MMI)
+    MMI->AnalyzeModule(M);
+  DW = getAnalysisIfAvailable<DwarfWriter>();
+  if (DW)
+    DW->BeginModule(&M, MMI, O, this, MAI);
+
+  return false;
+}
+
+void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const {
+  switch ((GlobalValue::LinkageTypes)Linkage) {
+  case GlobalValue::CommonLinkage:
+  case GlobalValue::LinkOnceAnyLinkage:
+  case GlobalValue::LinkOnceODRLinkage:
+  case GlobalValue::WeakAnyLinkage:
+  case GlobalValue::WeakODRLinkage:
+  case GlobalValue::LinkerPrivateLinkage:
+    if (MAI->getWeakDefDirective() != 0) {
+      // .globl _foo
+      OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
+      // .weak_definition _foo
+      OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
+    } else if (const char *LinkOnce = MAI->getLinkOnceDirective()) {
+      // .globl _foo
+      OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
+      // FIXME: linkonce should be a section attribute, handled by COFF Section
+      // assignment.
+      // http://sourceware.org/binutils/docs-2.20/as/Linkonce.html#Linkonce
+      // .linkonce discard
+      // FIXME: It would be nice to use .linkonce samesize for non-common
+      // globals.
+      O << LinkOnce;
+    } else {
+      // .weak _foo
+      OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
+    }
+    break;
+  case GlobalValue::DLLExportLinkage:
+  case GlobalValue::AppendingLinkage:
+    // FIXME: appending linkage variables should go into a section of
+    // their name or something.  For now, just emit them as external.
+  case GlobalValue::ExternalLinkage:
+    // If external or appending, declare as a global symbol.
+    // .globl _foo
+    OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
+    break;
+  case GlobalValue::PrivateLinkage:
+  case GlobalValue::InternalLinkage:
+    break;
+  default:
+    llvm_unreachable("Unknown linkage type!");
+  }
+}
+
+
+/// EmitGlobalVariable - Emit the specified global variable to the .s file.
+void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
+  if (!GV->hasInitializer())   // External globals require no code.
+    return;
+  
+  // Check to see if this is a special global used by LLVM, if so, emit it.
+  if (EmitSpecialLLVMGlobal(GV))
+    return;
+
+  MCSymbol *GVSym = GetGlobalValueSymbol(GV);
+  EmitVisibility(GVSym, GV->getVisibility());
+
+  if (MAI->hasDotTypeDotSizeDirective())
+    OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
+  
+  SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
+
+  const TargetData *TD = TM.getTargetData();
+  unsigned Size = TD->getTypeAllocSize(GV->getType()->getElementType());
+  unsigned AlignLog = TD->getPreferredAlignmentLog(GV);
+  
+  // Handle common and BSS local symbols (.lcomm).
+  if (GVKind.isCommon() || GVKind.isBSSLocal()) {
+    if (Size == 0) Size = 1;   // .comm Foo, 0 is undefined, avoid it.
+    
+    if (VerboseAsm) {
+      WriteAsOperand(OutStreamer.GetCommentOS(), GV,
+                     /*PrintType=*/false, GV->getParent());
+      OutStreamer.GetCommentOS() << '\n';
+    }
+    
+    // Handle common symbols.
+    if (GVKind.isCommon()) {
+      // .comm _foo, 42, 4
+      OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
+      return;
+    }
+    
+    // Handle local BSS symbols.
+    if (MAI->hasMachoZeroFillDirective()) {
+      const MCSection *TheSection =
+        getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
+      // .zerofill __DATA, __bss, _foo, 400, 5
+      OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
+      return;
+    }
+    
+    if (MAI->hasLCOMMDirective()) {
+      // .lcomm _foo, 42
+      OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
+      return;
+    }
+    
+    // .local _foo
+    OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
+    // .comm _foo, 42, 4
+    OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
+    return;
+  }
+  
+  const MCSection *TheSection =
+    getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
+
+  // Handle the zerofill directive on darwin, which is a special form of BSS
+  // emission.
+  if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
+    // .globl _foo
+    OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
+    // .zerofill __DATA, __common, _foo, 400, 5
+    OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
+    return;
+  }
+
+  OutStreamer.SwitchSection(TheSection);
+
+  EmitLinkage(GV->getLinkage(), GVSym);
+  EmitAlignment(AlignLog, GV);
+
+  if (VerboseAsm) {
+    WriteAsOperand(OutStreamer.GetCommentOS(), GV,
+                   /*PrintType=*/false, GV->getParent());
+    OutStreamer.GetCommentOS() << '\n';
+  }
+  OutStreamer.EmitLabel(GVSym);
+
+  EmitGlobalConstant(GV->getInitializer());
+
+  if (MAI->hasDotTypeDotSizeDirective())
+    // .size foo, 42
+    OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
+  
+  OutStreamer.AddBlankLine();
+}
+
+/// EmitFunctionHeader - This method emits the header for the current
+/// function.
+void AsmPrinter::EmitFunctionHeader() {
+  // Print out constants referenced by the function
+  EmitConstantPool();
+  
+  // Print the 'header' of function.
+  const Function *F = MF->getFunction();
+
+  OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
+  EmitVisibility(CurrentFnSym, F->getVisibility());
+
+  EmitLinkage(F->getLinkage(), CurrentFnSym);
+  EmitAlignment(MF->getAlignment(), F);
+
+  if (MAI->hasDotTypeDotSizeDirective())
+    OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
+
+  if (VerboseAsm) {
+    WriteAsOperand(OutStreamer.GetCommentOS(), F,
+                   /*PrintType=*/false, F->getParent());
+    OutStreamer.GetCommentOS() << '\n';
+  }
+
+  // Emit the CurrentFnSym.  This is a virtual function to allow targets to
+  // do their wild and crazy things as required.
+  EmitFunctionEntryLabel();
+  
+  // Add some workaround for linkonce linkage on Cygwin\MinGW.
+  if (MAI->getLinkOnceDirective() != 0 &&
+      (F->hasLinkOnceLinkage() || F->hasWeakLinkage()))
+    // FIXME: What is this?
+    O << "Lllvm$workaround$fake$stub$" << *CurrentFnSym << ":\n";
+  
+  // Emit pre-function debug and/or EH information.
+  if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
+    DW->BeginFunction(MF);
+}
+
+/// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
+/// function.  This can be overridden by targets as required to do custom stuff.
+void AsmPrinter::EmitFunctionEntryLabel() {
+  OutStreamer.EmitLabel(CurrentFnSym);
+}
+
+
+/// EmitComments - Pretty-print comments for instructions.
+static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
+  const MachineFunction *MF = MI.getParent()->getParent();
+  const TargetMachine &TM = MF->getTarget();
+  
+  if (!MI.getDebugLoc().isUnknown()) {
+    DILocation DLT = MF->getDILocation(MI.getDebugLoc());
+    
+    // Print source line info.
+    DIScope Scope = DLT.getScope();
+    // Omit the directory, because it's likely to be long and uninteresting.
+    if (!Scope.isNull())
+      CommentOS << Scope.getFilename();
+    else
+      CommentOS << "<unknown>";
+    CommentOS << ':' << DLT.getLineNumber();
+    if (DLT.getColumnNumber() != 0)
+      CommentOS << ':' << DLT.getColumnNumber();
+    CommentOS << '\n';
+  }
+  
+  // Check for spills and reloads
+  int FI;
+  
+  const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
+  
+  // We assume a single instruction only has a spill or reload, not
+  // both.
+  const MachineMemOperand *MMO;
+  if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
+    if (FrameInfo->isSpillSlotObjectIndex(FI)) {
+      MMO = *MI.memoperands_begin();
+      CommentOS << MMO->getSize() << "-byte Reload\n";
+    }
+  } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
+    if (FrameInfo->isSpillSlotObjectIndex(FI))
+      CommentOS << MMO->getSize() << "-byte Folded Reload\n";
+  } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
+    if (FrameInfo->isSpillSlotObjectIndex(FI)) {
+      MMO = *MI.memoperands_begin();
+      CommentOS << MMO->getSize() << "-byte Spill\n";
+    }
+  } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
+    if (FrameInfo->isSpillSlotObjectIndex(FI))
+      CommentOS << MMO->getSize() << "-byte Folded Spill\n";
+  }
+  
+  // Check for spill-induced copies
+  unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
+  if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
+                                     SrcSubIdx, DstSubIdx)) {
+    if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
+      CommentOS << " Reload Reuse\n";
+  }
+}
+
+
+
+/// EmitFunctionBody - This method emits the body and trailer for a
+/// function.
+void AsmPrinter::EmitFunctionBody() {
+  // Emit target-specific gunk before the function body.
+  EmitFunctionBodyStart();
+  
+  // Print out code for the function.
+  bool HasAnyRealCode = false;
+  for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
+       I != E; ++I) {
+    // Print a label for the basic block.
+    EmitBasicBlockStart(I);
+    for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
+         II != IE; ++II) {
+      // Print the assembly for the instruction.
+      if (!II->isLabel())
+        HasAnyRealCode = true;
+      
+      ++EmittedInsts;
+      
+      // FIXME: Clean up processDebugLoc.
+      processDebugLoc(II, true);
+      
+      if (VerboseAsm)
+        EmitComments(*II, OutStreamer.GetCommentOS());
+
+      switch (II->getOpcode()) {
+      case TargetOpcode::DBG_LABEL:
+      case TargetOpcode::EH_LABEL:
+      case TargetOpcode::GC_LABEL:
+        printLabelInst(II);
+        break;
+      case TargetOpcode::INLINEASM:
+        printInlineAsm(II);
+        break;
+      case TargetOpcode::IMPLICIT_DEF:
+        printImplicitDef(II);
+        break;
+      case TargetOpcode::KILL:
+        printKill(II);
+        break;
+      default:
+        EmitInstruction(II);
+        break;
+      }
+      
+      // FIXME: Clean up processDebugLoc.
+      processDebugLoc(II, false);
+    }
+  }
+  
+  // If the function is empty and the object file uses .subsections_via_symbols,
+  // then we need to emit *something* to the function body to prevent the
+  // labels from collapsing together.  Just emit a 0 byte.
+  if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)
+    OutStreamer.EmitIntValue(0, 1, 0/*addrspace*/);
+  
+  // Emit target-specific gunk after the function body.
+  EmitFunctionBodyEnd();
+  
+  if (MAI->hasDotTypeDotSizeDirective())
+    O << "\t.size\t" << *CurrentFnSym << ", .-" << *CurrentFnSym << '\n';
+  
+  // Emit post-function debug information.
+  if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
+    DW->EndFunction(MF);
+  
+  // Print out jump tables referenced by the function.
+  EmitJumpTableInfo();
+  
+  OutStreamer.AddBlankLine();
+}
+
+
+bool AsmPrinter::doFinalization(Module &M) {
+  // Emit global variables.
+  for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
+       I != E; ++I)
+    EmitGlobalVariable(I);
+  
+  // Emit final debug information.
+  if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling())
+    DW->EndModule();
+  
+  // If the target wants to know about weak references, print them all.
+  if (MAI->getWeakRefDirective()) {
+    // FIXME: This is not lazy, it would be nice to only print weak references
+    // to stuff that is actually used.  Note that doing so would require targets
+    // to notice uses in operands (due to constant exprs etc).  This should
+    // happen with the MC stuff eventually.
+
+    // Print out module-level global variables here.
+    for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
+         I != E; ++I) {
+      if (!I->hasExternalWeakLinkage()) continue;
+      OutStreamer.EmitSymbolAttribute(GetGlobalValueSymbol(I),
+                                      MCSA_WeakReference);
+    }
+    
+    for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
+      if (!I->hasExternalWeakLinkage()) continue;
+      OutStreamer.EmitSymbolAttribute(GetGlobalValueSymbol(I),
+                                      MCSA_WeakReference);
+    }
+  }
+
+  if (MAI->hasSetDirective()) {
+    OutStreamer.AddBlankLine();
+    for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
+         I != E; ++I) {
+      MCSymbol *Name = GetGlobalValueSymbol(I);
+
+      const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
+      MCSymbol *Target = GetGlobalValueSymbol(GV);
+
+      if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
+        OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
+      else if (I->hasWeakLinkage())
+        OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
+      else
+        assert(I->hasLocalLinkage() && "Invalid alias linkage");
+
+      EmitVisibility(Name, I->getVisibility());
+
+      // Emit the directives as assignments aka .set:
+      OutStreamer.EmitAssignment(Name, 
+                                 MCSymbolRefExpr::Create(Target, OutContext));
+    }
+  }
+
+  GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
+  assert(MI && "AsmPrinter didn't require GCModuleInfo?");
+  for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
+    if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
+      MP->finishAssembly(O, *this, *MAI);
+
+  // If we don't have any trampolines, then we don't require stack memory
+  // to be executable. Some targets have a directive to declare this.
+  Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
+  if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
+    if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
+      OutStreamer.SwitchSection(S);
+  
+  // Allow the target to emit any magic that it wants at the end of the file,
+  // after everything else has gone out.
+  EmitEndOfAsmFile(M);
+  
+  delete Mang; Mang = 0;
+  DW = 0; MMI = 0;
+  
+  OutStreamer.Finish();
+  return false;
+}
+
+void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
+  this->MF = &MF;
+  // Get the function symbol.
+  CurrentFnSym = GetGlobalValueSymbol(MF.getFunction());
+
+  if (VerboseAsm)
+    LI = &getAnalysis<MachineLoopInfo>();
+}
+
+namespace {
+  // SectionCPs - Keep track the alignment, constpool entries per Section.
+  struct SectionCPs {
+    const MCSection *S;
+    unsigned Alignment;
+    SmallVector<unsigned, 4> CPEs;
+    SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
+  };
+}
+
+/// EmitConstantPool - Print to the current output stream assembly
+/// representations of the constants in the constant pool MCP. This is
+/// used to print out constants which have been "spilled to memory" by
+/// the code generator.
+///
+void AsmPrinter::EmitConstantPool() {
+  const MachineConstantPool *MCP = MF->getConstantPool();
+  const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
+  if (CP.empty()) return;
+
+  // Calculate sections for constant pool entries. We collect entries to go into
+  // the same section together to reduce amount of section switch statements.
+  SmallVector<SectionCPs, 4> CPSections;
+  for (unsigned i = 0, e = CP.size(); i != e; ++i) {
+    const MachineConstantPoolEntry &CPE = CP[i];
+    unsigned Align = CPE.getAlignment();
+    
+    SectionKind Kind;
+    switch (CPE.getRelocationInfo()) {
+    default: llvm_unreachable("Unknown section kind");
+    case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
+    case 1:
+      Kind = SectionKind::getReadOnlyWithRelLocal();
+      break;
+    case 0:
+    switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
+    case 4:  Kind = SectionKind::getMergeableConst4(); break;
+    case 8:  Kind = SectionKind::getMergeableConst8(); break;
+    case 16: Kind = SectionKind::getMergeableConst16();break;
+    default: Kind = SectionKind::getMergeableConst(); break;
+    }
+    }
+
+    const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
+    
+    // The number of sections are small, just do a linear search from the
+    // last section to the first.
+    bool Found = false;
+    unsigned SecIdx = CPSections.size();
+    while (SecIdx != 0) {
+      if (CPSections[--SecIdx].S == S) {
+        Found = true;
+        break;
+      }
+    }
+    if (!Found) {
+      SecIdx = CPSections.size();
+      CPSections.push_back(SectionCPs(S, Align));
+    }
+
+    if (Align > CPSections[SecIdx].Alignment)
+      CPSections[SecIdx].Alignment = Align;
+    CPSections[SecIdx].CPEs.push_back(i);
+  }
+
+  // Now print stuff into the calculated sections.
+  for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
+    OutStreamer.SwitchSection(CPSections[i].S);
+    EmitAlignment(Log2_32(CPSections[i].Alignment));
+
+    unsigned Offset = 0;
+    for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
+      unsigned CPI = CPSections[i].CPEs[j];
+      MachineConstantPoolEntry CPE = CP[CPI];
+
+      // Emit inter-object padding for alignment.
+      unsigned AlignMask = CPE.getAlignment() - 1;
+      unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
+      OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
+
+      const Type *Ty = CPE.getType();
+      Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
+
+      // Emit the label with a comment on it.
+      if (VerboseAsm) {
+        OutStreamer.GetCommentOS() << "constant pool ";
+        WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
+                          MF->getFunction()->getParent());
+        OutStreamer.GetCommentOS() << '\n';
+      }
+      OutStreamer.EmitLabel(GetCPISymbol(CPI));
+
+      if (CPE.isMachineConstantPoolEntry())
+        EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
+      else
+        EmitGlobalConstant(CPE.Val.ConstVal);
+    }
+  }
+}
+
+/// EmitJumpTableInfo - Print assembly representations of the jump tables used
+/// by the current function to the current output stream.  
+///
+void AsmPrinter::EmitJumpTableInfo() {
+  const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
+  if (MJTI == 0) return;
+  const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
+  if (JT.empty()) return;
+
+  // Pick the directive to use to print the jump table entries, and switch to 
+  // the appropriate section.
+  const Function *F = MF->getFunction();
+  bool JTInDiffSection = false;
+  if (// In PIC mode, we need to emit the jump table to the same section as the
+      // function body itself, otherwise the label differences won't make sense.
+      // FIXME: Need a better predicate for this: what about custom entries?
+      MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
+      // We should also do if the section name is NULL or function is declared
+      // in discardable section
+      // FIXME: this isn't the right predicate, should be based on the MCSection
+      // for the function.
+      F->isWeakForLinker()) {
+    OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
+  } else {
+    // Otherwise, drop it in the readonly section.
+    const MCSection *ReadOnlySection = 
+      getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
+    OutStreamer.SwitchSection(ReadOnlySection);
+    JTInDiffSection = true;
+  }
+
+  EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
+  
+  for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
+    const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
+    
+    // If this jump table was deleted, ignore it. 
+    if (JTBBs.empty()) continue;
+
+    // For the EK_LabelDifference32 entry, if the target supports .set, emit a
+    // .set directive for each unique entry.  This reduces the number of
+    // relocations the assembler will generate for the jump table.
+    if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
+        MAI->hasSetDirective()) {
+      SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
+      const TargetLowering *TLI = TM.getTargetLowering();
+      const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
+      for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
+        const MachineBasicBlock *MBB = JTBBs[ii];
+        if (!EmittedSets.insert(MBB)) continue;
+        
+        // .set LJTSet, LBB32-base
+        const MCExpr *LHS =
+          MCSymbolRefExpr::Create(MBB->getSymbol(OutContext), OutContext);
+        OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
+                                MCBinaryExpr::CreateSub(LHS, Base, OutContext));
+      }
+    }          
+    
+    // On some targets (e.g. Darwin) we want to emit two consequtive labels
+    // before each jump table.  The first label is never referenced, but tells
+    // the assembler and linker the extents of the jump table object.  The
+    // second label is actually referenced by the code.
+    if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
+      // FIXME: This doesn't have to have any specific name, just any randomly
+      // named and numbered 'l' label would work.  Simplify GetJTISymbol.
+      OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
+
+    OutStreamer.EmitLabel(GetJTISymbol(JTI));
+
+    for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
+      EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
+  }
+}
+
+/// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
+/// current stream.
+void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
+                                    const MachineBasicBlock *MBB,
+                                    unsigned UID) const {
+  const MCExpr *Value = 0;
+  switch (MJTI->getEntryKind()) {
+  case MachineJumpTableInfo::EK_Custom32:
+    Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
+                                                              OutContext);
+    break;
+  case MachineJumpTableInfo::EK_BlockAddress:
+    // EK_BlockAddress - Each entry is a plain address of block, e.g.:
+    //     .word LBB123
+    Value = MCSymbolRefExpr::Create(MBB->getSymbol(OutContext), OutContext);
+    break;
+  case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
+    // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
+    // with a relocation as gp-relative, e.g.:
+    //     .gprel32 LBB123
+    MCSymbol *MBBSym = MBB->getSymbol(OutContext);
+    OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
+    return;
+  }
+
+  case MachineJumpTableInfo::EK_LabelDifference32: {
+    // EK_LabelDifference32 - Each entry is the address of the block minus
+    // the address of the jump table.  This is used for PIC jump tables where
+    // gprel32 is not supported.  e.g.:
+    //      .word LBB123 - LJTI1_2
+    // If the .set directive is supported, this is emitted as:
+    //      .set L4_5_set_123, LBB123 - LJTI1_2
+    //      .word L4_5_set_123
+    
+    // If we have emitted set directives for the jump table entries, print 
+    // them rather than the entries themselves.  If we're emitting PIC, then
+    // emit the table entries as differences between two text section labels.
+    if (MAI->hasSetDirective()) {
+      // If we used .set, reference the .set's symbol.
+      Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
+                                      OutContext);
+      break;
+    }
+    // Otherwise, use the difference as the jump table entry.
+    Value = MCSymbolRefExpr::Create(MBB->getSymbol(OutContext), OutContext);
+    const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
+    Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
+    break;
+  }
+  }
+  
+  assert(Value && "Unknown entry kind!");
+ 
+  unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
+  OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
+}
+
+
+/// EmitSpecialLLVMGlobal - Check to see if the specified global is a
+/// special global used by LLVM.  If so, emit it and return true, otherwise
+/// do nothing and return false.
+bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
+  if (GV->getName() == "llvm.used") {
+    if (MAI->hasNoDeadStrip())    // No need to emit this at all.
+      EmitLLVMUsedList(GV->getInitializer());
+    return true;
+  }
+
+  // Ignore debug and non-emitted data.  This handles llvm.compiler.used.
+  if (GV->getSection() == "llvm.metadata" ||
+      GV->hasAvailableExternallyLinkage())
+    return true;
+  
+  if (!GV->hasAppendingLinkage()) return false;
+
+  assert(GV->hasInitializer() && "Not a special LLVM global!");
+  
+  const TargetData *TD = TM.getTargetData();
+  unsigned Align = Log2_32(TD->getPointerPrefAlignment());
+  if (GV->getName() == "llvm.global_ctors") {
+    OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
+    EmitAlignment(Align, 0);
+    EmitXXStructorList(GV->getInitializer());
+    
+    if (TM.getRelocationModel() == Reloc::Static &&
+        MAI->hasStaticCtorDtorReferenceInStaticMode()) {
+      StringRef Sym(".constructors_used");
+      OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
+                                      MCSA_Reference);
+    }
+    return true;
+  } 
+  
+  if (GV->getName() == "llvm.global_dtors") {
+    OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
+    EmitAlignment(Align, 0);
+    EmitXXStructorList(GV->getInitializer());
+
+    if (TM.getRelocationModel() == Reloc::Static &&
+        MAI->hasStaticCtorDtorReferenceInStaticMode()) {
+      StringRef Sym(".destructors_used");
+      OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
+                                      MCSA_Reference);
+    }
+    return true;
+  }
+  
+  return false;
+}
+
+/// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
+/// global in the specified llvm.used list for which emitUsedDirectiveFor
+/// is true, as being used with this directive.
+void AsmPrinter::EmitLLVMUsedList(Constant *List) {
+  // Should be an array of 'i8*'.
+  ConstantArray *InitList = dyn_cast<ConstantArray>(List);
+  if (InitList == 0) return;
+  
+  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
+    const GlobalValue *GV =
+      dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
+    if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
+      OutStreamer.EmitSymbolAttribute(GetGlobalValueSymbol(GV),
+                                      MCSA_NoDeadStrip);
+  }
+}
+
+/// EmitXXStructorList - Emit the ctor or dtor list.  This just prints out the 
+/// function pointers, ignoring the init priority.
+void AsmPrinter::EmitXXStructorList(Constant *List) {
+  // Should be an array of '{ int, void ()* }' structs.  The first value is the
+  // init priority, which we ignore.
+  if (!isa<ConstantArray>(List)) return;
+  ConstantArray *InitList = cast<ConstantArray>(List);
+  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
+    if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
+      if (CS->getNumOperands() != 2) return;  // Not array of 2-element structs.
+
+      if (CS->getOperand(1)->isNullValue())
+        return;  // Found a null terminator, exit printing.
+      // Emit the function pointer.
+      EmitGlobalConstant(CS->getOperand(1));
+    }
+}
+
+//===--------------------------------------------------------------------===//
+// Emission and print routines
+//
+
+/// EmitInt8 - Emit a byte directive and value.
+///
+void AsmPrinter::EmitInt8(int Value) const {
+  OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
+}
+
+/// EmitInt16 - Emit a short directive and value.
+///
+void AsmPrinter::EmitInt16(int Value) const {
+  OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
+}
+
+/// EmitInt32 - Emit a long directive and value.
+///
+void AsmPrinter::EmitInt32(int Value) const {
+  OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
+}
+
+/// EmitInt64 - Emit a long long directive and value.
+///
+void AsmPrinter::EmitInt64(uint64_t Value) const {
+  OutStreamer.EmitIntValue(Value, 8, 0/*addrspace*/);
+}
+
+//===----------------------------------------------------------------------===//
+
+// EmitAlignment - Emit an alignment directive to the specified power of
+// two boundary.  For example, if you pass in 3 here, you will get an 8
+// byte alignment.  If a global value is specified, and if that global has
+// an explicit alignment requested, it will unconditionally override the
+// alignment request.  However, if ForcedAlignBits is specified, this value
+// has final say: the ultimate alignment will be the max of ForcedAlignBits
+// and the alignment computed with NumBits and the global.
+//
+// The algorithm is:
+//     Align = NumBits;
+//     if (GV && GV->hasalignment) Align = GV->getalignment();
+//     Align = std::max(Align, ForcedAlignBits);
+//
+void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
+                               unsigned ForcedAlignBits,
+                               bool UseFillExpr) const {
+  if (GV && GV->getAlignment())
+    NumBits = Log2_32(GV->getAlignment());
+  NumBits = std::max(NumBits, ForcedAlignBits);
+  
+  if (NumBits == 0) return;   // No need to emit alignment.
+  
+  unsigned FillValue = 0;
+  if (getCurrentSection()->getKind().isText())
+    FillValue = MAI->getTextAlignFillValue();
+  
+  OutStreamer.EmitValueToAlignment(1 << NumBits, FillValue, 1, 0);
+}
+
+/// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
+///
+static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
+  MCContext &Ctx = AP.OutContext;
+  
+  if (CV->isNullValue() || isa<UndefValue>(CV))
+    return MCConstantExpr::Create(0, Ctx);
+
+  if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
+    return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
+  
+  if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
+    return MCSymbolRefExpr::Create(AP.GetGlobalValueSymbol(GV), Ctx);
+  if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
+    return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
+  
+  const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
+  if (CE == 0) {
+    llvm_unreachable("Unknown constant value to lower!");
+    return MCConstantExpr::Create(0, Ctx);
+  }
+  
+  switch (CE->getOpcode()) {
+  default:
+    // If the code isn't optimized, there may be outstanding folding
+    // opportunities. Attempt to fold the expression using TargetData as a
+    // last resort before giving up.
+    if (Constant *C =
+          ConstantFoldConstantExpression(CE, AP.TM.getTargetData()))
+      if (C != CE)
+        return LowerConstant(C, AP);
+#ifndef NDEBUG
+    CE->dump();
+#endif
+    llvm_unreachable("FIXME: Don't support this constant expr");
+  case Instruction::GetElementPtr: {
+    const TargetData &TD = *AP.TM.getTargetData();
+    // Generate a symbolic expression for the byte address
+    const Constant *PtrVal = CE->getOperand(0);
+    SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
+    int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
+                                         IdxVec.size());
+    
+    const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
+    if (Offset == 0)
+      return Base;
+    
+    // Truncate/sext the offset to the pointer size.
+    if (TD.getPointerSizeInBits() != 64) {
+      int SExtAmount = 64-TD.getPointerSizeInBits();
+      Offset = (Offset << SExtAmount) >> SExtAmount;
+    }
+    
+    return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
+                                   Ctx);
+  }
+      
+  case Instruction::Trunc:
+    // We emit the value and depend on the assembler to truncate the generated
+    // expression properly.  This is important for differences between
+    // blockaddress labels.  Since the two labels are in the same function, it
+    // is reasonable to treat their delta as a 32-bit value.
+    // FALL THROUGH.
+  case Instruction::BitCast:
+    return LowerConstant(CE->getOperand(0), AP);
+
+  case Instruction::IntToPtr: {
+    const TargetData &TD = *AP.TM.getTargetData();
+    // Handle casts to pointers by changing them into casts to the appropriate
+    // integer type.  This promotes constant folding and simplifies this code.
+    Constant *Op = CE->getOperand(0);
+    Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
+                                      false/*ZExt*/);
+    return LowerConstant(Op, AP);
+  }
+    
+  case Instruction::PtrToInt: {
+    const TargetData &TD = *AP.TM.getTargetData();
+    // Support only foldable casts to/from pointers that can be eliminated by
+    // changing the pointer to the appropriately sized integer type.
+    Constant *Op = CE->getOperand(0);
+    const Type *Ty = CE->getType();
+
+    const MCExpr *OpExpr = LowerConstant(Op, AP);
+
+    // We can emit the pointer value into this slot if the slot is an
+    // integer slot equal to the size of the pointer.
+    if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
+      return OpExpr;
+
+    // Otherwise the pointer is smaller than the resultant integer, mask off
+    // the high bits so we are sure to get a proper truncation if the input is
+    // a constant expr.
+    unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
+    const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
+    return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
+  }
+      
+  // The MC library also has a right-shift operator, but it isn't consistently
+  // signed or unsigned between different targets.
+  case Instruction::Add:
+  case Instruction::Sub:
+  case Instruction::Mul:
+  case Instruction::SDiv:
+  case Instruction::SRem:
+  case Instruction::Shl:
+  case Instruction::And:
+  case Instruction::Or:
+  case Instruction::Xor: {
+    const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
+    const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
+    switch (CE->getOpcode()) {
+    default: llvm_unreachable("Unknown binary operator constant cast expr");
+    case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
+    case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
+    case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
+    case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
+    case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
+    case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
+    case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
+    case Instruction::Or:  return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
+    case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
+    }
+  }
+  }
+}
+
+static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
+                                    AsmPrinter &AP) {
+  if (AddrSpace != 0 || !CA->isString()) {
+    // Not a string.  Print the values in successive locations
+    for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
+      AP.EmitGlobalConstant(CA->getOperand(i), AddrSpace);
+    return;
+  }
+  
+  // Otherwise, it can be emitted as .ascii.
+  SmallVector<char, 128> TmpVec;
+  TmpVec.reserve(CA->getNumOperands());
+  for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
+    TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
+
+  AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
+}
+
+static void EmitGlobalConstantVector(const ConstantVector *CV,
+                                     unsigned AddrSpace, AsmPrinter &AP) {
+  for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
+    AP.EmitGlobalConstant(CV->getOperand(i), AddrSpace);
+}
+
+static void EmitGlobalConstantStruct(const ConstantStruct *CS,
+                                     unsigned AddrSpace, AsmPrinter &AP) {
+  // Print the fields in successive locations. Pad to align if needed!
+  const TargetData *TD = AP.TM.getTargetData();
+  unsigned Size = TD->getTypeAllocSize(CS->getType());
+  const StructLayout *Layout = TD->getStructLayout(CS->getType());
+  uint64_t SizeSoFar = 0;
+  for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
+    const Constant *Field = CS->getOperand(i);
+
+    // Check if padding is needed and insert one or more 0s.
+    uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
+    uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
+                        - Layout->getElementOffset(i)) - FieldSize;
+    SizeSoFar += FieldSize + PadSize;
+
+    // Now print the actual field value.
+    AP.EmitGlobalConstant(Field, AddrSpace);
+
+    // Insert padding - this may include padding to increase the size of the
+    // current field up to the ABI size (if the struct is not packed) as well
+    // as padding to ensure that the next field starts at the right offset.
+    AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
+  }
+  assert(SizeSoFar == Layout->getSizeInBytes() &&
+         "Layout of constant struct may be incorrect!");
+}
+
+static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
+                                 AsmPrinter &AP) {
+  // FP Constants are printed as integer constants to avoid losing
+  // precision.
+  if (CFP->getType()->isDoubleTy()) {
+    if (AP.VerboseAsm) {
+      double Val = CFP->getValueAPF().convertToDouble();
+      AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
+    }
+
+    uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
+    AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
+    return;
+  }
+  
+  if (CFP->getType()->isFloatTy()) {
+    if (AP.VerboseAsm) {
+      float Val = CFP->getValueAPF().convertToFloat();
+      AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
+    }
+    uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
+    AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
+    return;
+  }
+  
+  if (CFP->getType()->isX86_FP80Ty()) {
+    // all long double variants are printed as hex
+    // api needed to prevent premature destruction
+    APInt API = CFP->getValueAPF().bitcastToAPInt();
+    const uint64_t *p = API.getRawData();
+    if (AP.VerboseAsm) {
+      // Convert to double so we can print the approximate val as a comment.
+      APFloat DoubleVal = CFP->getValueAPF();
+      bool ignored;
+      DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
+                        &ignored);
+      AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
+        << DoubleVal.convertToDouble() << '\n';
+    }
+    
+    if (AP.TM.getTargetData()->isBigEndian()) {
+      AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
+      AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
+    } else {
+      AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
+      AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
+    }
+    
+    // Emit the tail padding for the long double.
+    const TargetData &TD = *AP.TM.getTargetData();
+    AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
+                             TD.getTypeStoreSize(CFP->getType()), AddrSpace);
+    return;
+  }
+  
+  assert(CFP->getType()->isPPC_FP128Ty() &&
+         "Floating point constant type not handled");
+  // All long double variants are printed as hex api needed to prevent
+  // premature destruction.
+  APInt API = CFP->getValueAPF().bitcastToAPInt();
+  const uint64_t *p = API.getRawData();
+  if (AP.TM.getTargetData()->isBigEndian()) {
+    AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
+    AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
+  } else {
+    AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
+    AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
+  }
+}
+
+static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
+                                       unsigned AddrSpace, AsmPrinter &AP) {
+  const TargetData *TD = AP.TM.getTargetData();
+  unsigned BitWidth = CI->getBitWidth();
+  assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
+
+  // We don't expect assemblers to support integer data directives
+  // for more than 64 bits, so we emit the data in at most 64-bit
+  // quantities at a time.
+  const uint64_t *RawData = CI->getValue().getRawData();
+  for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
+    uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
+    AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
+  }
+}
+
+/// EmitGlobalConstant - Print a general LLVM constant to the .s file.
+void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
+  if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
+    uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
+    if (Size == 0) Size = 1; // An empty "_foo:" followed by a section is undef.
+    return OutStreamer.EmitZeros(Size, AddrSpace);
+  }
+
+  if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
+    unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
+    switch (Size) {
+    case 1:
+    case 2:
+    case 4:
+    case 8:
+      if (VerboseAsm)
+        OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
+      OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
+      return;
+    default:
+      EmitGlobalConstantLargeInt(CI, AddrSpace, *this);
+      return;
+    }
+  }
+  
+  if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
+    return EmitGlobalConstantArray(CVA, AddrSpace, *this);
+  
+  if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
+    return EmitGlobalConstantStruct(CVS, AddrSpace, *this);
+
+  if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
+    return EmitGlobalConstantFP(CFP, AddrSpace, *this);
+  
+  if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
+    return EmitGlobalConstantVector(V, AddrSpace, *this);
+
+  if (isa<ConstantPointerNull>(CV)) {
+    unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
+    OutStreamer.EmitIntValue(0, Size, AddrSpace);
+    return;
+  }
+  
+  // Otherwise, it must be a ConstantExpr.  Lower it to an MCExpr, then emit it
+  // thread the streamer with EmitValue.
+  OutStreamer.EmitValue(LowerConstant(CV, *this),
+                        TM.getTargetData()->getTypeAllocSize(CV->getType()),
+                        AddrSpace);
+}
+
+void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
+  // Target doesn't support this yet!
+  llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
+}
+
+/// PrintSpecial - Print information related to the specified machine instr
+/// that is independent of the operand, and may be independent of the instr
+/// itself.  This can be useful for portably encoding the comment character
+/// or other bits of target-specific knowledge into the asmstrings.  The
+/// syntax used is ${:comment}.  Targets can override this to add support
+/// for their own strange codes.
+void AsmPrinter::PrintSpecial(const MachineInstr *MI, const char *Code) const {
+  if (!strcmp(Code, "private")) {
+    O << MAI->getPrivateGlobalPrefix();
+  } else if (!strcmp(Code, "comment")) {
+    if (VerboseAsm)
+      O << MAI->getCommentString();
+  } else if (!strcmp(Code, "uid")) {
+    // Comparing the address of MI isn't sufficient, because machineinstrs may
+    // be allocated to the same address across functions.
+    const Function *ThisF = MI->getParent()->getParent()->getFunction();
+    
+    // If this is a new LastFn instruction, bump the counter.
+    if (LastMI != MI || LastFn != ThisF) {
+      ++Counter;
+      LastMI = MI;
+      LastFn = ThisF;
+    }
+    O << Counter;
+  } else {
+    std::string msg;
+    raw_string_ostream Msg(msg);
+    Msg << "Unknown special formatter '" << Code
+         << "' for machine instr: " << *MI;
+    llvm_report_error(Msg.str());
+  }    
+}
+
+/// processDebugLoc - Processes the debug information of each machine
+/// instruction's DebugLoc.
+void AsmPrinter::processDebugLoc(const MachineInstr *MI, 
+                                 bool BeforePrintingInsn) {
+  if (!MAI || !DW || !MAI->doesSupportDebugInformation()
+      || !DW->ShouldEmitDwarfDebug())
+    return;
+  DebugLoc DL = MI->getDebugLoc();
+  if (DL.isUnknown())
+    return;
+  DILocation CurDLT = MF->getDILocation(DL);
+  if (CurDLT.getScope().isNull())
+    return;
+
+  if (!BeforePrintingInsn) {
+    // After printing instruction
+    DW->EndScope(MI);
+  } else if (CurDLT.getNode() != PrevDLT) {
+    unsigned L = DW->RecordSourceLine(CurDLT.getLineNumber(), 
+                                      CurDLT.getColumnNumber(),
+                                      CurDLT.getScope().getNode());
+    printLabel(L);
+    O << '\n';
+    DW->BeginScope(MI, L);
+    PrevDLT = CurDLT.getNode();
+  }
+}
+
+
+/// printInlineAsm - This method formats and prints the specified machine
+/// instruction that is an inline asm.
+void AsmPrinter::printInlineAsm(const MachineInstr *MI) const {
+  unsigned NumOperands = MI->getNumOperands();
+  
+  // Count the number of register definitions.
+  unsigned NumDefs = 0;
+  for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef();
+       ++NumDefs)
+    assert(NumDefs != NumOperands-1 && "No asm string?");
+  
+  assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?");
+
+  // Disassemble the AsmStr, printing out the literal pieces, the operands, etc.
+  const char *AsmStr = MI->getOperand(NumDefs).getSymbolName();
+
+  O << '\t';
+
+  // If this asmstr is empty, just print the #APP/#NOAPP markers.
+  // These are useful to see where empty asm's wound up.
+  if (AsmStr[0] == 0) {
+    O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t";
+    O << MAI->getCommentString() << MAI->getInlineAsmEnd() << '\n';
+    return;
+  }
+  
+  O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t";
+
+  // The variant of the current asmprinter.
+  int AsmPrinterVariant = MAI->getAssemblerDialect();
+
+  int CurVariant = -1;            // The number of the {.|.|.} region we are in.
+  const char *LastEmitted = AsmStr; // One past the last character emitted.
+  
+  while (*LastEmitted) {
+    switch (*LastEmitted) {
+    default: {
+      // Not a special case, emit the string section literally.
+      const char *LiteralEnd = LastEmitted+1;
+      while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' &&
+             *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n')
+        ++LiteralEnd;
+      if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
+        O.write(LastEmitted, LiteralEnd-LastEmitted);
+      LastEmitted = LiteralEnd;
+      break;
+    }
+    case '\n':
+      ++LastEmitted;   // Consume newline character.
+      O << '\n';       // Indent code with newline.
+      break;
+    case '$': {
+      ++LastEmitted;   // Consume '$' character.
+      bool Done = true;
+
+      // Handle escapes.
+      switch (*LastEmitted) {
+      default: Done = false; break;
+      case '$':     // $$ -> $
+        if (CurVariant == -1 || CurVariant == AsmPrinterVariant)
+          O << '$';
+        ++LastEmitted;  // Consume second '$' character.
+        break;
+      case '(':             // $( -> same as GCC's { character.
+        ++LastEmitted;      // Consume '(' character.
+        if (CurVariant != -1) {
+          llvm_report_error("Nested variants found in inline asm string: '"
+                            + std::string(AsmStr) + "'");
+        }
+        CurVariant = 0;     // We're in the first variant now.
+        break;
+      case '|':
+        ++LastEmitted;  // consume '|' character.
+        if (CurVariant == -1)
+          O << '|';       // this is gcc's behavior for | outside a variant
+        else
+          ++CurVariant;   // We're in the next variant.
+        break;
+      case ')':         // $) -> same as GCC's } char.
+        ++LastEmitted;  // consume ')' character.
+        if (CurVariant == -1)
+          O << '}';     // this is gcc's behavior for } outside a variant
+        else 
+          CurVariant = -1;
+        break;
+      }
+      if (Done) break;
+      
+      bool HasCurlyBraces = false;
+      if (*LastEmitted == '{') {     // ${variable}
+        ++LastEmitted;               // Consume '{' character.
+        HasCurlyBraces = true;
+      }
+      
+      // If we have ${:foo}, then this is not a real operand reference, it is a
+      // "magic" string reference, just like in .td files.  Arrange to call
+      // PrintSpecial.
+      if (HasCurlyBraces && *LastEmitted == ':') {
+        ++LastEmitted;
+        const char *StrStart = LastEmitted;
+        const char *StrEnd = strchr(StrStart, '}');
+        if (StrEnd == 0) {
+          llvm_report_error("Unterminated ${:foo} operand in inline asm string: '" 
+                            + std::string(AsmStr) + "'");
+        }
+        
+        std::string Val(StrStart, StrEnd);
+        PrintSpecial(MI, Val.c_str());
+        LastEmitted = StrEnd+1;
+        break;
+      }
+            
+      const char *IDStart = LastEmitted;
+      char *IDEnd;
+      errno = 0;
+      long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs.
+      if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) {
+        llvm_report_error("Bad $ operand number in inline asm string: '" 
+                          + std::string(AsmStr) + "'");
+      }
+      LastEmitted = IDEnd;
+      
+      char Modifier[2] = { 0, 0 };
+      
+      if (HasCurlyBraces) {
+        // If we have curly braces, check for a modifier character.  This
+        // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm.
+        if (*LastEmitted == ':') {
+          ++LastEmitted;    // Consume ':' character.
+          if (*LastEmitted == 0) {
+            llvm_report_error("Bad ${:} expression in inline asm string: '" 
+                              + std::string(AsmStr) + "'");
+          }
+          
+          Modifier[0] = *LastEmitted;
+          ++LastEmitted;    // Consume modifier character.
+        }
+        
+        if (*LastEmitted != '}') {
+          llvm_report_error("Bad ${} expression in inline asm string: '" 
+                            + std::string(AsmStr) + "'");
+        }
+        ++LastEmitted;    // Consume '}' character.
+      }
+      
+      if ((unsigned)Val >= NumOperands-1) {
+        llvm_report_error("Invalid $ operand number in inline asm string: '" 
+                          + std::string(AsmStr) + "'");
+      }
+      
+      // Okay, we finally have a value number.  Ask the target to print this
+      // operand!
+      if (CurVariant == -1 || CurVariant == AsmPrinterVariant) {
+        unsigned OpNo = 1;
+
+        bool Error = false;
+
+        // Scan to find the machine operand number for the operand.
+        for (; Val; --Val) {
+          if (OpNo >= MI->getNumOperands()) break;
+          unsigned OpFlags = MI->getOperand(OpNo).getImm();
+          OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1;
+        }
+
+        if (OpNo >= MI->getNumOperands()) {
+          Error = true;
+        } else {
+          unsigned OpFlags = MI->getOperand(OpNo).getImm();
+          ++OpNo;  // Skip over the ID number.
+
+          if (Modifier[0] == 'l')  // labels are target independent
+            O << *MI->getOperand(OpNo).getMBB()->getSymbol(OutContext);
+          else {
+            AsmPrinter *AP = const_cast<AsmPrinter*>(this);
+            if ((OpFlags & 7) == 4) {
+              Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant,
+                                                Modifier[0] ? Modifier : 0);
+            } else {
+              Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant,
+                                          Modifier[0] ? Modifier : 0);
+            }
+          }
+        }
+        if (Error) {
+          std::string msg;
+          raw_string_ostream Msg(msg);
+          Msg << "Invalid operand found in inline asm: '" << AsmStr << "'\n";
+          MI->print(Msg);
+          llvm_report_error(Msg.str());
+        }
+      }
+      break;
+    }
+    }
+  }
+  O << "\n\t" << MAI->getCommentString() << MAI->getInlineAsmEnd();
+  OutStreamer.AddBlankLine();
+}
+
+/// printImplicitDef - This method prints the specified machine instruction
+/// that is an implicit def.
+void AsmPrinter::printImplicitDef(const MachineInstr *MI) const {
+  if (!VerboseAsm) return;
+  O.PadToColumn(MAI->getCommentColumn());
+  O << MAI->getCommentString() << " implicit-def: "
+    << TRI->getName(MI->getOperand(0).getReg());
+  OutStreamer.AddBlankLine();
+}
+
+void AsmPrinter::printKill(const MachineInstr *MI) const {
+  if (!VerboseAsm) return;
+  O.PadToColumn(MAI->getCommentColumn());
+  O << MAI->getCommentString() << " kill:";
+  for (unsigned n = 0, e = MI->getNumOperands(); n != e; ++n) {
+    const MachineOperand &op = MI->getOperand(n);
+    assert(op.isReg() && "KILL instruction must have only register operands");
+    O << ' ' << TRI->getName(op.getReg()) << (op.isDef() ? "<def>" : "<kill>");
+  }
+  OutStreamer.AddBlankLine();
+}
+
+/// printLabel - This method prints a local label used by debug and
+/// exception handling tables.
+void AsmPrinter::printLabelInst(const MachineInstr *MI) const {
+  printLabel(MI->getOperand(0).getImm());
+  OutStreamer.AddBlankLine();
+}
+
+void AsmPrinter::printLabel(unsigned Id) const {
+  O << MAI->getPrivateGlobalPrefix() << "label" << Id << ':';
+}
+
+/// PrintAsmOperand - Print the specified operand of MI, an INLINEASM
+/// instruction, using the specified assembler variant.  Targets should
+/// override this to format as appropriate.
+bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
+                                 unsigned AsmVariant, const char *ExtraCode) {
+  // Target doesn't support this yet!
+  return true;
+}
+
+bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
+                                       unsigned AsmVariant,
+                                       const char *ExtraCode) {
+  // Target doesn't support this yet!
+  return true;
+}
+
+MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
+  return GetBlockAddressSymbol(BA->getFunction(), BA->getBasicBlock());
+}
+
+MCSymbol *AsmPrinter::GetBlockAddressSymbol(const Function *F,
+                                            const BasicBlock *BB) const {
+  assert(BB->hasName() &&
+         "Address of anonymous basic block not supported yet!");
+
+  // This code must use the function name itself, and not the function number,
+  // since it must be possible to generate the label name from within other
+  // functions.
+  SmallString<60> FnName;
+  Mang->getNameWithPrefix(FnName, F, false);
+
+  // FIXME: THIS IS BROKEN IF THE LLVM BASIC BLOCK DOESN'T HAVE A NAME!
+  SmallString<60> NameResult;
+  Mang->getNameWithPrefix(NameResult,
+                          StringRef("BA") + Twine((unsigned)FnName.size()) + 
+                          "_" + FnName.str() + "_" + BB->getName(), 
+                          Mangler::Private);
+
+  return OutContext.GetOrCreateSymbol(NameResult.str());
+}
+
+/// GetCPISymbol - Return the symbol for the specified constant pool entry.
+MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
+  SmallString<60> Name;
+  raw_svector_ostream(Name) << MAI->getPrivateGlobalPrefix() << "CPI"
+    << getFunctionNumber() << '_' << CPID;
+  return OutContext.GetOrCreateSymbol(Name.str());
+}
+
+/// GetJTISymbol - Return the symbol for the specified jump table entry.
+MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
+  return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
+}
+
+/// GetJTSetSymbol - Return the symbol for the specified jump table .set
+/// FIXME: privatize to AsmPrinter.
+MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
+  SmallString<60> Name;
+  raw_svector_ostream(Name) << MAI->getPrivateGlobalPrefix()
+    << getFunctionNumber() << '_' << UID << "_set_" << MBBID;
+  return OutContext.GetOrCreateSymbol(Name.str());
+}
+
+/// GetGlobalValueSymbol - Return the MCSymbol for the specified global
+/// value.
+MCSymbol *AsmPrinter::GetGlobalValueSymbol(const GlobalValue *GV) const {
+  SmallString<60> NameStr;
+  Mang->getNameWithPrefix(NameStr, GV, false);
+  return OutContext.GetOrCreateSymbol(NameStr.str());
+}
+
+/// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
+/// global value name as its base, with the specified suffix, and where the
+/// symbol is forced to have private linkage if ForcePrivate is true.
+MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
+                                                   StringRef Suffix,
+                                                   bool ForcePrivate) const {
+  SmallString<60> NameStr;
+  Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
+  NameStr.append(Suffix.begin(), Suffix.end());
+  return OutContext.GetOrCreateSymbol(NameStr.str());
+}
+
+/// GetExternalSymbolSymbol - Return the MCSymbol for the specified
+/// ExternalSymbol.
+MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
+  SmallString<60> NameStr;
+  Mang->getNameWithPrefix(NameStr, Sym);
+  return OutContext.GetOrCreateSymbol(NameStr.str());
+}  
+
+
+
+/// PrintParentLoopComment - Print comments about parent loops of this one.
+static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
+                                   unsigned FunctionNumber) {
+  if (Loop == 0) return;
+  PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
+  OS.indent(Loop->getLoopDepth()*2)
+    << "Parent Loop BB" << FunctionNumber << "_"
+    << Loop->getHeader()->getNumber()
+    << " Depth=" << Loop->getLoopDepth() << '\n';
+}
+
+
+/// PrintChildLoopComment - Print comments about child loops within
+/// the loop for this basic block, with nesting.
+static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
+                                  unsigned FunctionNumber) {
+  // Add child loop information
+  for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
+    OS.indent((*CL)->getLoopDepth()*2)
+      << "Child Loop BB" << FunctionNumber << "_"
+      << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
+      << '\n';
+    PrintChildLoopComment(OS, *CL, FunctionNumber);
+  }
+}
+
+/// PrintBasicBlockLoopComments - Pretty-print comments for basic blocks.
+static void PrintBasicBlockLoopComments(const MachineBasicBlock &MBB,
+                                        const MachineLoopInfo *LI,
+                                        const AsmPrinter &AP) {
+  // Add loop depth information
+  const MachineLoop *Loop = LI->getLoopFor(&MBB);
+  if (Loop == 0) return;
+  
+  MachineBasicBlock *Header = Loop->getHeader();
+  assert(Header && "No header for loop");
+  
+  // If this block is not a loop header, just print out what is the loop header
+  // and return.
+  if (Header != &MBB) {
+    AP.OutStreamer.AddComment("  in Loop: Header=BB" +
+                              Twine(AP.getFunctionNumber())+"_" +
+                              Twine(Loop->getHeader()->getNumber())+
+                              " Depth="+Twine(Loop->getLoopDepth()));
+    return;
+  }
+  
+  // Otherwise, it is a loop header.  Print out information about child and
+  // parent loops.
+  raw_ostream &OS = AP.OutStreamer.GetCommentOS();
+  
+  PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber()); 
+  
+  OS << "=>";
+  OS.indent(Loop->getLoopDepth()*2-2);
+  
+  OS << "This ";
+  if (Loop->empty())
+    OS << "Inner ";
+  OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
+  
+  PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
+}
+
+
+/// EmitBasicBlockStart - This method prints the label for the specified
+/// MachineBasicBlock, an alignment (if present) and a comment describing
+/// it if appropriate.
+void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
+  // Emit an alignment directive for this block, if needed.
+  if (unsigned Align = MBB->getAlignment())
+    EmitAlignment(Log2_32(Align));
+
+  // If the block has its address taken, emit a special label to satisfy
+  // references to the block. This is done so that we don't need to
+  // remember the number of this label, and so that we can make
+  // forward references to labels without knowing what their numbers
+  // will be.
+  if (MBB->hasAddressTaken()) {
+    const BasicBlock *BB = MBB->getBasicBlock();
+    if (VerboseAsm)
+      OutStreamer.AddComment("Address Taken");
+    OutStreamer.EmitLabel(GetBlockAddressSymbol(BB->getParent(), BB));
+  }
+
+  // Print the main label for the block.
+  if (MBB->pred_empty() || MBB->isOnlyReachableByFallthrough()) {
+    if (VerboseAsm) {
+      // NOTE: Want this comment at start of line.
+      O << MAI->getCommentString() << " BB#" << MBB->getNumber() << ':';
+      if (const BasicBlock *BB = MBB->getBasicBlock())
+        if (BB->hasName())
+          OutStreamer.AddComment("%" + BB->getName());
+      
+      PrintBasicBlockLoopComments(*MBB, LI, *this);
+      OutStreamer.AddBlankLine();
+    }
+  } else {
+    if (VerboseAsm) {
+      if (const BasicBlock *BB = MBB->getBasicBlock())
+        if (BB->hasName())
+          OutStreamer.AddComment("%" + BB->getName());
+      PrintBasicBlockLoopComments(*MBB, LI, *this);
+    }
+
+    OutStreamer.EmitLabel(MBB->getSymbol(OutContext));
+  }
+}
+
+void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
+  MCSymbolAttr Attr = MCSA_Invalid;
+  
+  switch (Visibility) {
+  default: break;
+  case GlobalValue::HiddenVisibility:
+    Attr = MAI->getHiddenVisibilityAttr();
+    break;
+  case GlobalValue::ProtectedVisibility:
+    Attr = MAI->getProtectedVisibilityAttr();
+    break;
+  }
+
+  if (Attr != MCSA_Invalid)
+    OutStreamer.EmitSymbolAttribute(Sym, Attr);
+}
+
+void AsmPrinter::printOffset(int64_t Offset) const {
+  if (Offset > 0)
+    O << '+' << Offset;
+  else if (Offset < 0)
+    O << Offset;
+}
+
+GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
+  if (!S->usesMetadata())
+    return 0;
+  
+  gcp_iterator GCPI = GCMetadataPrinters.find(S);
+  if (GCPI != GCMetadataPrinters.end())
+    return GCPI->second;
+  
+  const char *Name = S->getName().c_str();
+  
+  for (GCMetadataPrinterRegistry::iterator
+         I = GCMetadataPrinterRegistry::begin(),
+         E = GCMetadataPrinterRegistry::end(); I != E; ++I)
+    if (strcmp(Name, I->getName()) == 0) {
+      GCMetadataPrinter *GMP = I->instantiate();
+      GMP->S = S;
+      GCMetadataPrinters.insert(std::make_pair(S, GMP));
+      return GMP;
+    }
+  
+  llvm_report_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
+  return 0;
+}
+
diff --git a/lib/CodeGen/AsmPrinter/CMakeLists.txt b/lib/CodeGen/AsmPrinter/CMakeLists.txt
new file mode 100644
index 0000000000..066aaab48c
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/CMakeLists.txt
@@ -0,0 +1,10 @@
+add_llvm_library(LLVMAsmPrinter
+  AsmPrinter.cpp
+  DIE.cpp
+  DwarfDebug.cpp
+  DwarfException.cpp
+  DwarfLabel.cpp
+  DwarfPrinter.cpp
+  DwarfWriter.cpp
+  OcamlGCPrinter.cpp
+  )
diff --git a/lib/CodeGen/AsmPrinter/DIE.cpp b/lib/CodeGen/AsmPrinter/DIE.cpp
new file mode 100644
index 0000000000..349e0ac40f
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/DIE.cpp
@@ -0,0 +1,431 @@
+//===--- lib/CodeGen/DIE.cpp - DWARF Info Entries -------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Data structures for DWARF info entries.
+// 
+//===----------------------------------------------------------------------===//
+
+#include "DIE.h"
+#include "DwarfPrinter.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/FormattedStream.h"
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+// DIEAbbrevData Implementation
+//===----------------------------------------------------------------------===//
+
+/// Profile - Used to gather unique data for the abbreviation folding set.
+///
+void DIEAbbrevData::Profile(FoldingSetNodeID &ID) const {
+  ID.AddInteger(Attribute);
+  ID.AddInteger(Form);
+}
+
+//===----------------------------------------------------------------------===//
+// DIEAbbrev Implementation
+//===----------------------------------------------------------------------===//
+
+/// Profile - Used to gather unique data for the abbreviation folding set.
+///
+void DIEAbbrev::Profile(FoldingSetNodeID &ID) const {
+  ID.AddInteger(Tag);
+  ID.AddInteger(ChildrenFlag);
+
+  // For each attribute description.
+  for (unsigned i = 0, N = Data.size(); i < N; ++i)
+    Data[i].Profile(ID);
+}
+
+/// Emit - Print the abbreviation using the specified asm printer.
+///
+void DIEAbbrev::Emit(const DwarfPrinter *DP) const {
+  // Emit its Dwarf tag type.
+  // FIXME: Doing work even in non-asm-verbose runs.
+  DP->EmitULEB128(Tag, dwarf::TagString(Tag));
+
+  // Emit whether it has children DIEs.
+  // FIXME: Doing work even in non-asm-verbose runs.
+  DP->EmitULEB128(ChildrenFlag, dwarf::ChildrenString(ChildrenFlag));
+
+  // For each attribute description.
+  for (unsigned i = 0, N = Data.size(); i < N; ++i) {
+    const DIEAbbrevData &AttrData = Data[i];
+
+    // Emit attribute type.
+    // FIXME: Doing work even in non-asm-verbose runs.
+    DP->EmitULEB128(AttrData.getAttribute(),
+                    dwarf::AttributeString(AttrData.getAttribute()));
+
+    // Emit form type.
+    // FIXME: Doing work even in non-asm-verbose runs.
+    DP->EmitULEB128(AttrData.getForm(),
+                    dwarf::FormEncodingString(AttrData.getForm()));
+  }
+
+  // Mark end of abbreviation.
+  DP->EmitULEB128(0, "EOM(1)");
+  DP->EmitULEB128(0, "EOM(2)");
+}
+
+#ifndef NDEBUG
+void DIEAbbrev::print(raw_ostream &O) {
+  O << "Abbreviation @"
+    << format("0x%lx", (long)(intptr_t)this)
+    << "  "
+    << dwarf::TagString(Tag)
+    << " "
+    << dwarf::ChildrenString(ChildrenFlag)
+    << '\n';
+
+  for (unsigned i = 0, N = Data.size(); i < N; ++i) {
+    O << "  "
+      << dwarf::AttributeString(Data[i].getAttribute())
+      << "  "
+      << dwarf::FormEncodingString(Data[i].getForm())
+      << '\n';
+  }
+}
+void DIEAbbrev::dump() { print(dbgs()); }
+#endif
+
+//===----------------------------------------------------------------------===//
+// DIE Implementation
+//===----------------------------------------------------------------------===//
+
+DIE::~DIE() {
+  for (unsigned i = 0, N = Children.size(); i < N; ++i)
+    delete Children[i];
+}
+
+/// addSiblingOffset - Add a sibling offset field to the front of the DIE.
+///
+void DIE::addSiblingOffset() {
+  DIEInteger *DI = new DIEInteger(0);
+  Values.insert(Values.begin(), DI);
+  Abbrev.AddFirstAttribute(dwarf::DW_AT_sibling, dwarf::DW_FORM_ref4);
+}
+
+#ifndef NDEBUG
+void DIE::print(raw_ostream &O, unsigned IncIndent) {
+  IndentCount += IncIndent;
+  const std::string Indent(IndentCount, ' ');
+  bool isBlock = Abbrev.getTag() == 0;
+
+  if (!isBlock) {
+    O << Indent
+      << "Die: "
+      << format("0x%lx", (long)(intptr_t)this)
+      << ", Offset: " << Offset
+      << ", Size: " << Size
+      << "\n";
+
+    O << Indent
+      << dwarf::TagString(Abbrev.getTag())
+      << " "
+      << dwarf::ChildrenString(Abbrev.getChildrenFlag());
+  } else {
+    O << "Size: " << Size;
+  }
+  O << "\n";
+
+  const SmallVector<DIEAbbrevData, 8> &Data = Abbrev.getData();
+
+  IndentCount += 2;
+  for (unsigned i = 0, N = Data.size(); i < N; ++i) {
+    O << Indent;
+
+    if (!isBlock)
+      O << dwarf::AttributeString(Data[i].getAttribute());
+    else
+      O << "Blk[" << i << "]";
+
+    O <<  "  "
+      << dwarf::FormEncodingString(Data[i].getForm())
+      << " ";
+    Values[i]->print(O);
+    O << "\n";
+  }
+  IndentCount -= 2;
+
+  for (unsigned j = 0, M = Children.size(); j < M; ++j) {
+    Children[j]->print(O, 4);
+  }
+
+  if (!isBlock) O << "\n";
+  IndentCount -= IncIndent;
+}
+
+void DIE::dump() {
+  print(dbgs());
+}
+#endif
+
+
+#ifndef NDEBUG
+void DIEValue::dump() {
+  print(dbgs());
+}
+#endif
+
+//===----------------------------------------------------------------------===//
+// DIEInteger Implementation
+//===----------------------------------------------------------------------===//
+
+/// EmitValue - Emit integer of appropriate size.
+///
+void DIEInteger::EmitValue(DwarfPrinter *D, unsigned Form) const {
+  const AsmPrinter *Asm = D->getAsm();
+  unsigned Size = ~0U;
+  switch (Form) {
+  case dwarf::DW_FORM_flag:  // Fall thru
+  case dwarf::DW_FORM_ref1:  // Fall thru
+  case dwarf::DW_FORM_data1: Size = 1; break;
+  case dwarf::DW_FORM_ref2:  // Fall thru
+  case dwarf::DW_FORM_data2: Size = 2; break;
+  case dwarf::DW_FORM_ref4:  // Fall thru
+  case dwarf::DW_FORM_data4: Size = 4; break;
+  case dwarf::DW_FORM_ref8:  // Fall thru
+  case dwarf::DW_FORM_data8: Size = 8; break;
+  case dwarf::DW_FORM_udata: D->EmitULEB128(Integer); return;
+  case dwarf::DW_FORM_sdata: D->EmitSLEB128(Integer, ""); return;
+  default: llvm_unreachable("DIE Value form not supported yet");
+  }
+  Asm->OutStreamer.EmitIntValue(Integer, Size, 0/*addrspace*/);
+}
+
+/// SizeOf - Determine size of integer value in bytes.
+///
+unsigned DIEInteger::SizeOf(const TargetData *TD, unsigned Form) const {
+  switch (Form) {
+  case dwarf::DW_FORM_flag:  // Fall thru
+  case dwarf::DW_FORM_ref1:  // Fall thru
+  case dwarf::DW_FORM_data1: return sizeof(int8_t);
+  case dwarf::DW_FORM_ref2:  // Fall thru
+  case dwarf::DW_FORM_data2: return sizeof(int16_t);
+  case dwarf::DW_FORM_ref4:  // Fall thru
+  case dwarf::DW_FORM_data4: return sizeof(int32_t);
+  case dwarf::DW_FORM_ref8:  // Fall thru
+  case dwarf::DW_FORM_data8: return sizeof(int64_t);
+  case dwarf::DW_FORM_udata: return MCAsmInfo::getULEB128Size(Integer);
+  case dwarf::DW_FORM_sdata: return MCAsmInfo::getSLEB128Size(Integer);
+  default: llvm_unreachable("DIE Value form not supported yet"); break;
+  }
+  return 0;
+}
+
+#ifndef NDEBUG
+void DIEInteger::print(raw_ostream &O) {
+  O << "Int: " << (int64_t)Integer
+    << format("  0x%llx", (unsigned long long)Integer);
+}
+#endif
+
+//===----------------------------------------------------------------------===//
+// DIEString Implementation
+//===----------------------------------------------------------------------===//
+
+/// EmitValue - Emit string value.
+///
+void DIEString::EmitValue(DwarfPrinter *D, unsigned Form) const {
+  D->getAsm()->OutStreamer.EmitBytes(Str, /*addrspace*/0);
+  // Emit nul terminator.
+  D->getAsm()->OutStreamer.EmitIntValue(0, 1, /*addrspace*/0);
+}
+
+#ifndef NDEBUG
+void DIEString::print(raw_ostream &O) {
+  O << "Str: \"" << Str << "\"";
+}
+#endif
+
+//===----------------------------------------------------------------------===//
+// DIEDwarfLabel Implementation
+//===----------------------------------------------------------------------===//
+
+/// EmitValue - Emit label value.
+///
+void DIEDwarfLabel::EmitValue(DwarfPrinter *D, unsigned Form) const {
+  bool IsSmall = Form == dwarf::DW_FORM_data4;
+  D->EmitReference(Label, false, IsSmall);
+}
+
+/// SizeOf - Determine size of label value in bytes.
+///
+unsigned DIEDwarfLabel::SizeOf(const TargetData *TD, unsigned Form) const {
+  if (Form == dwarf::DW_FORM_data4) return 4;
+  return TD->getPointerSize();
+}
+
+#ifndef NDEBUG
+void DIEDwarfLabel::print(raw_ostream &O) {
+  O << "Lbl: ";
+  Label.print(O);
+}
+#endif
+
+//===----------------------------------------------------------------------===//
+// DIEObjectLabel Implementation
+//===----------------------------------------------------------------------===//
+
+/// EmitValue - Emit label value.
+///
+void DIEObjectLabel::EmitValue(DwarfPrinter *D, unsigned Form) const {
+  bool IsSmall = Form == dwarf::DW_FORM_data4;
+  D->EmitReference(Sym, false, IsSmall);
+}
+
+/// SizeOf - Determine size of label value in bytes.
+///
+unsigned DIEObjectLabel::SizeOf(const TargetData *TD, unsigned Form) const {
+  if (Form == dwarf::DW_FORM_data4) return 4;
+  return TD->getPointerSize();
+}
+
+#ifndef NDEBUG
+void DIEObjectLabel::print(raw_ostream &O) {
+  O << "Obj: " << Sym->getName();
+}
+#endif
+
+//===----------------------------------------------------------------------===//
+// DIESectionOffset Implementation
+//===----------------------------------------------------------------------===//
+
+/// EmitValue - Emit delta value.
+///
+void DIESectionOffset::EmitValue(DwarfPrinter *D, unsigned Form) const {
+  bool IsSmall = Form == dwarf::DW_FORM_data4;
+  D->EmitSectionOffset(Label.getTag(), Section.getTag(),
+                       Label.getNumber(), Section.getNumber(),
+                       IsSmall, IsEH, UseSet);
+}
+
+/// SizeOf - Determine size of delta value in bytes.
+///
+unsigned DIESectionOffset::SizeOf(const TargetData *TD, unsigned Form) const {
+  if (Form == dwarf::DW_FORM_data4) return 4;
+  return TD->getPointerSize();
+}
+
+#ifndef NDEBUG
+void DIESectionOffset::print(raw_ostream &O) {
+  O << "Off: ";
+  Label.print(O);
+  O << "-";
+  Section.print(O);
+  O << "-" << IsEH << "-" << UseSet;
+}
+#endif
+
+//===----------------------------------------------------------------------===//
+// DIEDelta Implementation
+//===----------------------------------------------------------------------===//
+
+/// EmitValue - Emit delta value.
+///
+void DIEDelta::EmitValue(DwarfPrinter *D, unsigned Form) const {
+  bool IsSmall = Form == dwarf::DW_FORM_data4;
+  D->EmitDifference(LabelHi, LabelLo, IsSmall);
+}
+
+/// SizeOf - Determine size of delta value in bytes.
+///
+unsigned DIEDelta::SizeOf(const TargetData *TD, unsigned Form) const {
+  if (Form == dwarf::DW_FORM_data4) return 4;
+  return TD->getPointerSize();
+}
+
+#ifndef NDEBUG
+void DIEDelta::print(raw_ostream &O) {
+  O << "Del: ";
+  LabelHi.print(O);
+  O << "-";
+  LabelLo.print(O);
+}
+#endif
+
+//===----------------------------------------------------------------------===//
+// DIEEntry Implementation
+//===----------------------------------------------------------------------===//
+
+/// EmitValue - Emit debug information entry offset.
+///
+void DIEEntry::EmitValue(DwarfPrinter *D, unsigned Form) const {
+  D->getAsm()->EmitInt32(Entry->getOffset());
+}
+
+#ifndef NDEBUG
+void DIEEntry::print(raw_ostream &O) {
+  O << format("Die: 0x%lx", (long)(intptr_t)Entry);
+}
+#endif
+
+//===----------------------------------------------------------------------===//
+// DIEBlock Implementation
+//===----------------------------------------------------------------------===//
+
+/// ComputeSize - calculate the size of the block.
+///
+unsigned DIEBlock::ComputeSize(const TargetData *TD) {
+  if (!Size) {
+    const SmallVector<DIEAbbrevData, 8> &AbbrevData = Abbrev.getData();
+    for (unsigned i = 0, N = Values.size(); i < N; ++i)
+      Size += Values[i]->SizeOf(TD, AbbrevData[i].getForm());
+  }
+
+  return Size;
+}
+
+/// EmitValue - Emit block data.
+///
+void DIEBlock::EmitValue(DwarfPrinter *D, unsigned Form) const {
+  const AsmPrinter *Asm = D->getAsm();
+  switch (Form) {
+  case dwarf::DW_FORM_block1: Asm->EmitInt8(Size);         break;
+  case dwarf::DW_FORM_block2: Asm->EmitInt16(Size);        break;
+  case dwarf::DW_FORM_block4: Asm->EmitInt32(Size);        break;
+  case dwarf::DW_FORM_block:  D->EmitULEB128(Size); break;
+  default: llvm_unreachable("Improper form for block");         break;
+  }
+
+  const SmallVector<DIEAbbrevData, 8> &AbbrevData = Abbrev.getData();
+  for (unsigned i = 0, N = Values.size(); i < N; ++i) {
+    Asm->O << '\n';
+    Values[i]->EmitValue(D, AbbrevData[i].getForm());
+  }
+}
+
+/// SizeOf - Determine size of block data in bytes.
+///
+unsigned DIEBlock::SizeOf(const TargetData *TD, unsigned Form) const {
+  switch (Form) {
+  case dwarf::DW_FORM_block1: return Size + sizeof(int8_t);
+  case dwarf::DW_FORM_block2: return Size + sizeof(int16_t);
+  case dwarf::DW_FORM_block4: return Size + sizeof(int32_t);
+  case dwarf::DW_FORM_block: return Size + MCAsmInfo::getULEB128Size(Size);
+  default: llvm_unreachable("Improper form for block"); break;
+  }
+  return 0;
+}
+
+#ifndef NDEBUG
+void DIEBlock::print(raw_ostream &O) {
+  O << "Blk: ";
+  DIE::print(O, 5);
+}
+#endif
diff --git a/lib/CodeGen/AsmPrinter/DIE.h b/lib/CodeGen/AsmPrinter/DIE.h
new file mode 100644
index 0000000000..af90289e5f
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/DIE.h
@@ -0,0 +1,494 @@
+//===--- lib/CodeGen/DIE.h - DWARF Info Entries -----------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Data structures for DWARF info entries.
+// 
+//===----------------------------------------------------------------------===//
+
+#ifndef CODEGEN_ASMPRINTER_DIE_H__
+#define CODEGEN_ASMPRINTER_DIE_H__
+
+#include "DwarfLabel.h"
+#include "llvm/ADT/FoldingSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/Dwarf.h"
+#include <vector>
+
+namespace llvm {
+  class AsmPrinter;
+  class DwarfPrinter;
+  class TargetData;
+  class MCSymbol;
+
+  //===--------------------------------------------------------------------===//
+  /// DIEAbbrevData - Dwarf abbreviation data, describes the one attribute of a
+  /// Dwarf abbreviation.
+  class DIEAbbrevData {
+    /// Attribute - Dwarf attribute code.
+    ///
+    unsigned Attribute;
+
+    /// Form - Dwarf form code.
+    ///
+    unsigned Form;
+  public:
+    DIEAbbrevData(unsigned A, unsigned F) : Attribute(A), Form(F) {}
+
+    // Accessors.
+    unsigned getAttribute() const { return Attribute; }
+    unsigned getForm()      const { return Form; }
+
+    /// Profile - Used to gather unique data for the abbreviation folding set.
+    ///
+    void Profile(FoldingSetNodeID &ID) const;
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// DIEAbbrev - Dwarf abbreviation, describes the organization of a debug
+  /// information object.
+  class DIEAbbrev : public FoldingSetNode {
+    /// Tag - Dwarf tag code.
+    ///
+    unsigned Tag;
+
+    /// Unique number for node.
+    ///
+    unsigned Number;
+
+    /// ChildrenFlag - Dwarf children flag.
+    ///
+    unsigned ChildrenFlag;
+
+    /// Data - Raw data bytes for abbreviation.
+    ///
+    SmallVector<DIEAbbrevData, 8> Data;
+
+  public:
+    DIEAbbrev(unsigned T, unsigned C) : Tag(T), ChildrenFlag(C), Data() {}
+    virtual ~DIEAbbrev() {}
+
+    // Accessors.
+    unsigned getTag() const { return Tag; }
+    unsigned getNumber() const { return Number; }
+    unsigned getChildrenFlag() const { return ChildrenFlag; }
+    const SmallVector<DIEAbbrevData, 8> &getData() const { return Data; }
+    void setTag(unsigned T) { Tag = T; }
+    void setChildrenFlag(unsigned CF) { ChildrenFlag = CF; }
+    void setNumber(unsigned N) { Number = N; }
+
+    /// AddAttribute - Adds another set of attribute information to the
+    /// abbreviation.
+    void AddAttribute(unsigned Attribute, unsigned Form) {
+      Data.push_back(DIEAbbrevData(Attribute, Form));
+    }
+
+    /// AddFirstAttribute - Adds a set of attribute information to the front
+    /// of the abbreviation.
+    void AddFirstAttribute(unsigned Attribute, unsigned Form) {
+      Data.insert(Data.begin(), DIEAbbrevData(Attribute, Form));
+    }
+
+    /// Profile - Used to gather unique data for the abbreviation folding set.
+    ///
+    void Profile(FoldingSetNodeID &ID) const;
+
+    /// Emit - Print the abbreviation using the specified asm printer.
+    ///
+    void Emit(const DwarfPrinter *DP) const;
+
+#ifndef NDEBUG
+    void print(raw_ostream &O);
+    void dump();
+#endif
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// DIE - A structured debug information entry.  Has an abbreviation which
+  /// describes it's organization.
+  class CompileUnit;
+  class DIEValue;
+
+  class DIE {
+  protected:
+    /// Abbrev - Buffer for constructing abbreviation.
+    ///
+    DIEAbbrev Abbrev;
+
+    /// Offset - Offset in debug info section.
+    ///
+    unsigned Offset;
+
+    /// Size - Size of instance + children.
+    ///
+    unsigned Size;
+
+    /// Children DIEs.
+    ///
+    std::vector<DIE *> Children;
+
+    DIE *Parent;
+
+    /// Attributes values.
+    ///
+    SmallVector<DIEValue*, 32> Values;
+
+    // Private data for print()
+    mutable unsigned IndentCount;
+  public:
+    explicit DIE(unsigned Tag)
+      : Abbrev(Tag, dwarf::DW_CHILDREN_no), Offset(0),
+        Size(0), Parent (0), IndentCount(0) {}
+    virtual ~DIE();
+
+    // Accessors.
+    DIEAbbrev &getAbbrev() { return Abbrev; }
+    unsigned getAbbrevNumber() const { return Abbrev.getNumber(); }
+    unsigned getTag() const { return Abbrev.getTag(); }
+    unsigned getOffset() const { return Offset; }
+    unsigned getSize() const { return Size; }
+    const std::vector<DIE *> &getChildren() const { return Children; }
+    SmallVector<DIEValue*, 32> &getValues() { return Values; }
+    DIE *getParent() const { return Parent; }
+    void setTag(unsigned Tag) { Abbrev.setTag(Tag); }
+    void setOffset(unsigned O) { Offset = O; }
+    void setSize(unsigned S) { Size = S; }
+    void setParent(DIE *P) { Parent = P; }
+    
+    /// addValue - Add a value and attributes to a DIE.
+    ///
+    void addValue(unsigned Attribute, unsigned Form, DIEValue *Value) {
+      Abbrev.AddAttribute(Attribute, Form);
+      Values.push_back(Value);
+    }
+
+    /// SiblingOffset - Return the offset of the debug information entry's
+    /// sibling.
+    unsigned getSiblingOffset() const { return Offset + Size; }
+
+    /// addSiblingOffset - Add a sibling offset field to the front of the DIE.
+    ///
+    void addSiblingOffset();
+
+    /// addChild - Add a child to the DIE.
+    ///
+    void addChild(DIE *Child) {
+      if (Child->getParent()) {
+        assert (Child->getParent() == this && "Unexpected DIE Parent!");
+        return;
+      }
+      Abbrev.setChildrenFlag(dwarf::DW_CHILDREN_yes);
+      Children.push_back(Child);
+      Child->setParent(this);
+    }
+
+#ifndef NDEBUG
+    void print(raw_ostream &O, unsigned IncIndent = 0);
+    void dump();
+#endif
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// DIEValue - A debug information entry value.
+  ///
+  class DIEValue {
+  public:
+    enum {
+      isInteger,
+      isString,
+      isLabel,
+      isAsIsLabel,
+      isSectionOffset,
+      isDelta,
+      isEntry,
+      isBlock
+    };
+  protected:
+    /// Type - Type of data stored in the value.
+    ///
+    unsigned Type;
+  public:
+    explicit DIEValue(unsigned T) : Type(T) {}
+    virtual ~DIEValue() {}
+
+    // Accessors
+    unsigned getType()  const { return Type; }
+
+    /// EmitValue - Emit value via the Dwarf writer.
+    ///
+    virtual void EmitValue(DwarfPrinter *D, unsigned Form) const = 0;
+
+    /// SizeOf - Return the size of a value in bytes.
+    ///
+    virtual unsigned SizeOf(const TargetData *TD, unsigned Form) const = 0;
+
+    // Implement isa/cast/dyncast.
+    static bool classof(const DIEValue *) { return true; }
+
+#ifndef NDEBUG
+    virtual void print(raw_ostream &O) = 0;
+    void dump();
+#endif
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// DIEInteger - An integer value DIE.
+  ///
+  class DIEInteger : public DIEValue {
+    uint64_t Integer;
+  public:
+    explicit DIEInteger(uint64_t I) : DIEValue(isInteger), Integer(I) {}
+
+    /// BestForm - Choose the best form for integer.
+    ///
+    static unsigned BestForm(bool IsSigned, uint64_t Int) {
+      if (IsSigned) {
+        if ((char)Int == (signed)Int)   return dwarf::DW_FORM_data1;
+        if ((short)Int == (signed)Int)  return dwarf::DW_FORM_data2;
+        if ((int)Int == (signed)Int)    return dwarf::DW_FORM_data4;
+      } else {
+        if ((unsigned char)Int == Int)  return dwarf::DW_FORM_data1;
+        if ((unsigned short)Int == Int) return dwarf::DW_FORM_data2;
+        if ((unsigned int)Int == Int)   return dwarf::DW_FORM_data4;
+      }
+      return dwarf::DW_FORM_data8;
+    }
+
+    /// EmitValue - Emit integer of appropriate size.
+    ///
+    virtual void EmitValue(DwarfPrinter *D, unsigned Form) const;
+
+    /// SizeOf - Determine size of integer value in bytes.
+    ///
+    virtual unsigned SizeOf(const TargetData *TD, unsigned Form) const;
+
+
+    // Implement isa/cast/dyncast.
+    static bool classof(const DIEInteger *) { return true; }
+    static bool classof(const DIEValue *I) { return I->getType() == isInteger; }
+
+#ifndef NDEBUG
+    virtual void print(raw_ostream &O);
+#endif
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// DIEString - A string value DIE. This DIE keeps string reference only.
+  ///
+  class DIEString : public DIEValue {
+    const StringRef Str;
+  public:
+    explicit DIEString(const StringRef S) : DIEValue(isString), Str(S) {}
+
+    /// EmitValue - Emit string value.
+    ///
+    virtual void EmitValue(DwarfPrinter *D, unsigned Form) const;
+
+    /// SizeOf - Determine size of string value in bytes.
+    ///
+    virtual unsigned SizeOf(const TargetData *, unsigned /*Form*/) const {
+      return Str.size() + sizeof(char); // sizeof('\0');
+    }
+
+    // Implement isa/cast/dyncast.
+    static bool classof(const DIEString *) { return true; }
+    static bool classof(const DIEValue *S) { return S->getType() == isString; }
+
+#ifndef NDEBUG
+    virtual void print(raw_ostream &O);
+#endif
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// DIEDwarfLabel - A Dwarf internal label expression DIE.
+  //
+  class DIEDwarfLabel : public DIEValue {
+    const DWLabel Label;
+  public:
+    explicit DIEDwarfLabel(const DWLabel &L) : DIEValue(isLabel), Label(L) {}
+
+    /// EmitValue - Emit label value.
+    ///
+    virtual void EmitValue(DwarfPrinter *D, unsigned Form) const;
+
+    /// SizeOf - Determine size of label value in bytes.
+    ///
+    virtual unsigned SizeOf(const TargetData *TD, unsigned Form) const;
+
+    // Implement isa/cast/dyncast.
+    static bool classof(const DIEDwarfLabel *)  { return true; }
+    static bool classof(const DIEValue *L) { return L->getType() == isLabel; }
+
+#ifndef NDEBUG
+    virtual void print(raw_ostream &O);
+#endif
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// DIEObjectLabel - A label to an object in code or data.
+  //
+  class DIEObjectLabel : public DIEValue {
+    const MCSymbol *Sym;
+  public:
+    explicit DIEObjectLabel(const MCSymbol *S)
+      : DIEValue(isAsIsLabel), Sym(S) {}
+
+    /// EmitValue - Emit label value.
+    ///
+    virtual void EmitValue(DwarfPrinter *D, unsigned Form) const;
+
+    /// SizeOf - Determine size of label value in bytes.
+    ///
+    virtual unsigned SizeOf(const TargetData *TD, unsigned Form) const;
+
+    // Implement isa/cast/dyncast.
+    static bool classof(const DIEObjectLabel *) { return true; }
+    static bool classof(const DIEValue *L) {
+      return L->getType() == isAsIsLabel;
+    }
+
+#ifndef NDEBUG
+    virtual void print(raw_ostream &O);
+#endif
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// DIESectionOffset - A section offset DIE.
+  ///
+  class DIESectionOffset : public DIEValue {
+    const DWLabel Label;
+    const DWLabel Section;
+    bool IsEH : 1;
+    bool UseSet : 1;
+  public:
+    DIESectionOffset(const DWLabel &Lab, const DWLabel &Sec,
+                     bool isEH = false, bool useSet = true)
+      : DIEValue(isSectionOffset), Label(Lab), Section(Sec),
+        IsEH(isEH), UseSet(useSet) {}
+
+    /// EmitValue - Emit section offset.
+    ///
+    virtual void EmitValue(DwarfPrinter *D, unsigned Form) const;
+
+    /// SizeOf - Determine size of section offset value in bytes.
+    ///
+    virtual unsigned SizeOf(const TargetData *TD, unsigned Form) const;
+
+    // Implement isa/cast/dyncast.
+    static bool classof(const DIESectionOffset *)  { return true; }
+    static bool classof(const DIEValue *D) {
+      return D->getType() == isSectionOffset;
+    }
+
+#ifndef NDEBUG
+    virtual void print(raw_ostream &O);
+#endif
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// DIEDelta - A simple label difference DIE.
+  ///
+  class DIEDelta : public DIEValue {
+    const DWLabel LabelHi;
+    const DWLabel LabelLo;
+  public:
+    DIEDelta(const DWLabel &Hi, const DWLabel &Lo)
+      : DIEValue(isDelta), LabelHi(Hi), LabelLo(Lo) {}
+
+    /// EmitValue - Emit delta value.
+    ///
+    virtual void EmitValue(DwarfPrinter *D, unsigned Form) const;
+
+    /// SizeOf - Determine size of delta value in bytes.
+    ///
+    virtual unsigned SizeOf(const TargetData *TD, unsigned Form) const;
+
+    // Implement isa/cast/dyncast.
+    static bool classof(const DIEDelta *)  { return true; }
+    static bool classof(const DIEValue *D) { return D->getType() == isDelta; }
+
+#ifndef NDEBUG
+    virtual void print(raw_ostream &O);
+#endif
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// DIEntry - A pointer to another debug information entry.  An instance of
+  /// this class can also be used as a proxy for a debug information entry not
+  /// yet defined (ie. types.)
+  class DIEEntry : public DIEValue {
+    DIE *Entry;
+  public:
+    explicit DIEEntry(DIE *E) : DIEValue(isEntry), Entry(E) {}
+
+    DIE *getEntry() const { return Entry; }
+    void setEntry(DIE *E) { Entry = E; }
+
+    /// EmitValue - Emit debug information entry offset.
+    ///
+    virtual void EmitValue(DwarfPrinter *D, unsigned Form) const;
+
+    /// SizeOf - Determine size of debug information entry in bytes.
+    ///
+    virtual unsigned SizeOf(const TargetData *TD, unsigned Form) const {
+      return sizeof(int32_t);
+    }
+
+    // Implement isa/cast/dyncast.
+    static bool classof(const DIEEntry *)  { return true; }
+    static bool classof(const DIEValue *E) { return E->getType() == isEntry; }
+
+#ifndef NDEBUG
+    virtual void print(raw_ostream &O);
+#endif
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// DIEBlock - A block of values.  Primarily used for location expressions.
+  //
+  class DIEBlock : public DIEValue, public DIE {
+    unsigned Size;                // Size in bytes excluding size header.
+  public:
+    DIEBlock()
+      : DIEValue(isBlock), DIE(0), Size(0) {}
+    virtual ~DIEBlock() {}
+
+    /// ComputeSize - calculate the size of the block.
+    ///
+    unsigned ComputeSize(const TargetData *TD);
+
+    /// BestForm - Choose the best form for data.
+    ///
+    unsigned BestForm() const {
+      if ((unsigned char)Size == Size)  return dwarf::DW_FORM_block1;
+      if ((unsigned short)Size == Size) return dwarf::DW_FORM_block2;
+      if ((unsigned int)Size == Size)   return dwarf::DW_FORM_block4;
+      return dwarf::DW_FORM_block;
+    }
+
+    /// EmitValue - Emit block data.
+    ///
+    virtual void EmitValue(DwarfPrinter *D, unsigned Form) const;
+
+    /// SizeOf - Determine size of block data in bytes.
+    ///
+    virtual unsigned SizeOf(const TargetData *TD, unsigned Form) const;
+
+    // Implement isa/cast/dyncast.
+    static bool classof(const DIEBlock *)  { return true; }
+    static bool classof(const DIEValue *E) { return E->getType() == isBlock; }
+
+#ifndef NDEBUG
+    virtual void print(raw_ostream &O);
+#endif
+  };
+
+} // end llvm namespace
+
+#endif
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
new file mode 100644
index 0000000000..5093dd9a9c
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -0,0 +1,3011 @@
+//===-- llvm/CodeGen/DwarfDebug.cpp - Dwarf Debug Framework ---------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for writing dwarf debug info into asm files.
+//
+//===----------------------------------------------------------------------===//
+#define DEBUG_TYPE "dwarfdebug"
+#include "DwarfDebug.h"
+#include "llvm/Module.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/Target/Mangler.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetFrameInfo.h"
+#include "llvm/Target/TargetLoweringObjectFile.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/ValueHandle.h"
+#include "llvm/Support/FormattedStream.h"
+#include "llvm/Support/Timer.h"
+#include "llvm/System/Path.h"
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+
+/// Configuration values for initial hash set sizes (log2).
+///
+static const unsigned InitAbbreviationsSetSize = 9; // log2(512)
+
+namespace llvm {
+
+//===----------------------------------------------------------------------===//
+/// CompileUnit - This dwarf writer support class manages information associate
+/// with a source file.
+class CompileUnit {
+  /// ID - File identifier for source.
+  ///
+  unsigned ID;
+
+  /// Die - Compile unit debug information entry.
+  ///
+  DIE *CUDie;
+
+  /// IndexTyDie - An anonymous type for index type.
+  DIE *IndexTyDie;
+
+  /// GVToDieMap - Tracks the mapping of unit level debug informaton
+  /// variables to debug information entries.
+  /// FIXME : Rename GVToDieMap -> NodeToDieMap
+  DenseMap<MDNode *, DIE *> GVToDieMap;
+
+  /// GVToDIEEntryMap - Tracks the mapping of unit level debug informaton
+  /// descriptors to debug information entries using a DIEEntry proxy.
+  /// FIXME : Rename
+  DenseMap<MDNode *, DIEEntry *> GVToDIEEntryMap;
+
+  /// Globals - A map of globally visible named entities for this unit.
+  ///
+  StringMap<DIE*> Globals;
+
+  /// GlobalTypes - A map of globally visible types for this unit.
+  ///
+  StringMap<DIE*> GlobalTypes;
+
+public:
+  CompileUnit(unsigned I, DIE *D)
+    : ID(I), CUDie(D), IndexTyDie(0) {}
+  ~CompileUnit() { delete CUDie; delete IndexTyDie; }
+
+  // Accessors.
+  unsigned getID()                  const { return ID; }
+  DIE* getCUDie()                   const { return CUDie; }
+  const StringMap<DIE*> &getGlobals()     const { return Globals; }
+  const StringMap<DIE*> &getGlobalTypes() const { return GlobalTypes; }
+
+  /// hasContent - Return true if this compile unit has something to write out.
+  ///
+  bool hasContent() const { return !CUDie->getChildren().empty(); }
+
+  /// addGlobal - Add a new global entity to the compile unit.
+  ///
+  void addGlobal(const std::string &Name, DIE *Die) { Globals[Name] = Die; }
+
+  /// addGlobalType - Add a new global type to the compile unit.
+  ///
+  void addGlobalType(const std::string &Name, DIE *Die) { 
+    GlobalTypes[Name] = Die; 
+  }
+
+  /// getDIE - Returns the debug information entry map slot for the
+  /// specified debug variable.
+  DIE *getDIE(MDNode *N) { return GVToDieMap.lookup(N); }
+
+  /// insertDIE - Insert DIE into the map.
+  void insertDIE(MDNode *N, DIE *D) {
+    GVToDieMap.insert(std::make_pair(N, D));
+  }
+
+  /// getDIEEntry - Returns the debug information entry for the speciefied
+  /// debug variable.
+  DIEEntry *getDIEEntry(MDNode *N) { 
+    DenseMap<MDNode *, DIEEntry *>::iterator I = GVToDIEEntryMap.find(N);
+    if (I == GVToDIEEntryMap.end())
+      return NULL;
+    return I->second;
+  }
+
+  /// insertDIEEntry - Insert debug information entry into the map.
+  void insertDIEEntry(MDNode *N, DIEEntry *E) {
+    GVToDIEEntryMap.insert(std::make_pair(N, E));
+  }
+
+  /// addDie - Adds or interns the DIE to the compile unit.
+  ///
+  void addDie(DIE *Buffer) {
+    this->CUDie->addChild(Buffer);
+  }
+
+  // getIndexTyDie - Get an anonymous type for index type.
+  DIE *getIndexTyDie() {
+    return IndexTyDie;
+  }
+
+  // setIndexTyDie - Set D as anonymous type for index which can be reused
+  // later.
+  void setIndexTyDie(DIE *D) {
+    IndexTyDie = D;
+  }
+
+};
+
+//===----------------------------------------------------------------------===//
+/// DbgVariable - This class is used to track local variable information.
+///
+class DbgVariable {
+  DIVariable Var;                    // Variable Descriptor.
+  unsigned FrameIndex;               // Variable frame index.
+  DbgVariable *AbstractVar;          // Abstract variable for this variable.
+  DIE *TheDIE;
+public:
+  DbgVariable(DIVariable V, unsigned I)
+    : Var(V), FrameIndex(I), AbstractVar(0), TheDIE(0)  {}
+
+  // Accessors.
+  DIVariable getVariable()           const { return Var; }
+  unsigned getFrameIndex()           const { return FrameIndex; }
+  void setAbstractVariable(DbgVariable *V) { AbstractVar = V; }
+  DbgVariable *getAbstractVariable() const { return AbstractVar; }
+  void setDIE(DIE *D)                      { TheDIE = D; }
+  DIE *getDIE()                      const { return TheDIE; }
+};
+
+//===----------------------------------------------------------------------===//
+/// DbgScope - This class is used to track scope information.
+///
+class DbgScope {
+  DbgScope *Parent;                   // Parent to this scope.
+  DIDescriptor Desc;                  // Debug info descriptor for scope.
+  // Location at which this scope is inlined.
+  AssertingVH<MDNode> InlinedAtLocation;  
+  bool AbstractScope;                 // Abstract Scope
+  unsigned StartLabelID;              // Label ID of the beginning of scope.
+  unsigned EndLabelID;                // Label ID of the end of scope.
+  const MachineInstr *LastInsn;       // Last instruction of this scope.
+  const MachineInstr *FirstInsn;      // First instruction of this scope.
+  SmallVector<DbgScope *, 4> Scopes;  // Scopes defined in scope.
+  SmallVector<DbgVariable *, 8> Variables;// Variables declared in scope.
+
+  // Private state for dump()
+  mutable unsigned IndentLevel;
+public:
+  DbgScope(DbgScope *P, DIDescriptor D, MDNode *I = 0)
+    : Parent(P), Desc(D), InlinedAtLocation(I), AbstractScope(false),
+      StartLabelID(0), EndLabelID(0),
+      LastInsn(0), FirstInsn(0), IndentLevel(0) {}
+  virtual ~DbgScope();
+
+  // Accessors.
+  DbgScope *getParent()          const { return Parent; }
+  void setParent(DbgScope *P)          { Parent = P; }
+  DIDescriptor getDesc()         const { return Desc; }
+  MDNode *getInlinedAt()         const {
+    return InlinedAtLocation;
+  }
+  MDNode *getScopeNode()         const { return Desc.getNode(); }
+  unsigned getStartLabelID()     const { return StartLabelID; }
+  unsigned getEndLabelID()       const { return EndLabelID; }
+  SmallVector<DbgScope *, 4> &getScopes() { return Scopes; }
+  SmallVector<DbgVariable *, 8> &getVariables() { return Variables; }
+  void setStartLabelID(unsigned S) { StartLabelID = S; }
+  void setEndLabelID(unsigned E)   { EndLabelID = E; }
+  void setLastInsn(const MachineInstr *MI) { LastInsn = MI; }
+  const MachineInstr *getLastInsn()      { return LastInsn; }
+  void setFirstInsn(const MachineInstr *MI) { FirstInsn = MI; }
+  void setAbstractScope() { AbstractScope = true; }
+  bool isAbstractScope() const { return AbstractScope; }
+  const MachineInstr *getFirstInsn()      { return FirstInsn; }
+
+  /// addScope - Add a scope to the scope.
+  ///
+  void addScope(DbgScope *S) { Scopes.push_back(S); }
+
+  /// addVariable - Add a variable to the scope.
+  ///
+  void addVariable(DbgVariable *V) { Variables.push_back(V); }
+
+  void fixInstructionMarkers(DenseMap<const MachineInstr *, 
+                             unsigned> &MIIndexMap) {
+    assert (getFirstInsn() && "First instruction is missing!");
+    
+    // Use the end of last child scope as end of this scope.
+    SmallVector<DbgScope *, 4> &Scopes = getScopes();
+    const MachineInstr *LastInsn = getFirstInsn();
+    unsigned LIndex = 0;
+    if (Scopes.empty()) {
+      assert (getLastInsn() && "Inner most scope does not have last insn!");
+      return;
+    }
+    for (SmallVector<DbgScope *, 4>::iterator SI = Scopes.begin(),
+           SE = Scopes.end(); SI != SE; ++SI) {
+      DbgScope *DS = *SI;
+      DS->fixInstructionMarkers(MIIndexMap);
+      const MachineInstr *DSLastInsn = DS->getLastInsn();
+      unsigned DSI = MIIndexMap[DSLastInsn];
+      if (DSI > LIndex) {
+        LastInsn = DSLastInsn;
+        LIndex = DSI;
+      }
+    }
+    setLastInsn(LastInsn);
+  }
+
+#ifndef NDEBUG
+  void dump() const;
+#endif
+};
+
+#ifndef NDEBUG
+void DbgScope::dump() const {
+  raw_ostream &err = dbgs();
+  err.indent(IndentLevel);
+  MDNode *N = Desc.getNode();
+  N->dump();
+  err << " [" << StartLabelID << ", " << EndLabelID << "]\n";
+  if (AbstractScope)
+    err << "Abstract Scope\n";
+
+  IndentLevel += 2;
+  if (!Scopes.empty())
+    err << "Children ...\n";
+  for (unsigned i = 0, e = Scopes.size(); i != e; ++i)
+    if (Scopes[i] != this)
+      Scopes[i]->dump();
+
+  IndentLevel -= 2;
+}
+#endif
+
+DbgScope::~DbgScope() {
+  for (unsigned i = 0, N = Scopes.size(); i < N; ++i)
+    delete Scopes[i];
+  for (unsigned j = 0, M = Variables.size(); j < M; ++j)
+    delete Variables[j];
+}
+
+} // end llvm namespace
+
+DwarfDebug::DwarfDebug(raw_ostream &OS, AsmPrinter *A, const MCAsmInfo *T)
+  : DwarfPrinter(OS, A, T, "dbg"), ModuleCU(0),
+    AbbreviationsSet(InitAbbreviationsSetSize), Abbreviations(),
+    DIEValues(), StringPool(),
+    SectionSourceLines(), didInitial(false), shouldEmit(false),
+    CurrentFnDbgScope(0), DebugTimer(0) {
+  if (TimePassesIsEnabled)
+    DebugTimer = new Timer("Dwarf Debug Writer");
+}
+DwarfDebug::~DwarfDebug() {
+  for (unsigned j = 0, M = DIEValues.size(); j < M; ++j)
+    delete DIEValues[j];
+
+  delete DebugTimer;
+}
+
+/// assignAbbrevNumber - Define a unique number for the abbreviation.
+///
+void DwarfDebug::assignAbbrevNumber(DIEAbbrev &Abbrev) {
+  // Profile the node so that we can make it unique.
+  FoldingSetNodeID ID;
+  Abbrev.Profile(ID);
+
+  // Check the set for priors.
+  DIEAbbrev *InSet = AbbreviationsSet.GetOrInsertNode(&Abbrev);
+
+  // If it's newly added.
+  if (InSet == &Abbrev) {
+    // Add to abbreviation list.
+    Abbreviations.push_back(&Abbrev);
+
+    // Assign the vector position + 1 as its number.
+    Abbrev.setNumber(Abbreviations.size());
+  } else {
+    // Assign existing abbreviation number.
+    Abbrev.setNumber(InSet->getNumber());
+  }
+}
+
+/// createDIEEntry - Creates a new DIEEntry to be a proxy for a debug
+/// information entry.
+DIEEntry *DwarfDebug::createDIEEntry(DIE *Entry) {
+  DIEEntry *Value = new DIEEntry(Entry);
+  DIEValues.push_back(Value);
+  return Value;
+}
+
+/// addUInt - Add an unsigned integer attribute data and value.
+///
+void DwarfDebug::addUInt(DIE *Die, unsigned Attribute,
+                         unsigned Form, uint64_t Integer) {
+  if (!Form) Form = DIEInteger::BestForm(false, Integer);
+  DIEValue *Value = new DIEInteger(Integer);
+  DIEValues.push_back(Value);
+  Die->addValue(Attribute, Form, Value);
+}
+
+/// addSInt - Add an signed integer attribute data and value.
+///
+void DwarfDebug::addSInt(DIE *Die, unsigned Attribute,
+                         unsigned Form, int64_t Integer) {
+  if (!Form) Form = DIEInteger::BestForm(true, Integer);
+  DIEValue *Value = new DIEInteger(Integer);
+  DIEValues.push_back(Value);
+  Die->addValue(Attribute, Form, Value);
+}
+
+/// addString - Add a string attribute data and value. DIEString only
+/// keeps string reference. 
+void DwarfDebug::addString(DIE *Die, unsigned Attribute, unsigned Form,
+                           StringRef String) {
+  DIEValue *Value = new DIEString(String);
+  DIEValues.push_back(Value);
+  Die->addValue(Attribute, Form, Value);
+}
+
+/// addLabel - Add a Dwarf label attribute data and value.
+///
+void DwarfDebug::addLabel(DIE *Die, unsigned Attribute, unsigned Form,
+                          const DWLabel &Label) {
+  DIEValue *Value = new DIEDwarfLabel(Label);
+  DIEValues.push_back(Value);
+  Die->addValue(Attribute, Form, Value);
+}
+
+/// addObjectLabel - Add an non-Dwarf label attribute data and value.
+///
+void DwarfDebug::addObjectLabel(DIE *Die, unsigned Attribute, unsigned Form,
+                                const MCSymbol *Sym) {
+  DIEValue *Value = new DIEObjectLabel(Sym);
+  DIEValues.push_back(Value);
+  Die->addValue(Attribute, Form, Value);
+}
+
+/// addSectionOffset - Add a section offset label attribute data and value.
+///
+void DwarfDebug::addSectionOffset(DIE *Die, unsigned Attribute, unsigned Form,
+                                  const DWLabel &Label, const DWLabel &Section,
+                                  bool isEH, bool useSet) {
+  DIEValue *Value = new DIESectionOffset(Label, Section, isEH, useSet);
+  DIEValues.push_back(Value);
+  Die->addValue(Attribute, Form, Value);
+}
+
+/// addDelta - Add a label delta attribute data and value.
+///
+void DwarfDebug::addDelta(DIE *Die, unsigned Attribute, unsigned Form,
+                          const DWLabel &Hi, const DWLabel &Lo) {
+  DIEValue *Value = new DIEDelta(Hi, Lo);
+  DIEValues.push_back(Value);
+  Die->addValue(Attribute, Form, Value);
+}
+
+/// addBlock - Add block data.
+///
+void DwarfDebug::addBlock(DIE *Die, unsigned Attribute, unsigned Form,
+                          DIEBlock *Block) {
+  Block->ComputeSize(TD);
+  DIEValues.push_back(Block);
+  Die->addValue(Attribute, Block->BestForm(), Block);
+}
+
+/// addSourceLine - Add location information to specified debug information
+/// entry.
+void DwarfDebug::addSourceLine(DIE *Die, const DIVariable *V) {
+  // If there is no compile unit specified, don't add a line #.
+  if (V->getCompileUnit().isNull())
+    return;
+
+  unsigned Line = V->getLineNumber();
+  unsigned FileID = findCompileUnit(V->getCompileUnit())->getID();
+  assert(FileID && "Invalid file id");
+  addUInt(Die, dwarf::DW_AT_decl_file, 0, FileID);
+  addUInt(Die, dwarf::DW_AT_decl_line, 0, Line);
+}
+
+/// addSourceLine - Add location information to specified debug information
+/// entry.
+void DwarfDebug::addSourceLine(DIE *Die, const DIGlobal *G) {
+  // If there is no compile unit specified, don't add a line #.
+  if (G->getCompileUnit().isNull())
+    return;
+
+  unsigned Line = G->getLineNumber();
+  unsigned FileID = findCompileUnit(G->getCompileUnit())->getID();
+  assert(FileID && "Invalid file id");
+  addUInt(Die, dwarf::DW_AT_decl_file, 0, FileID);
+  addUInt(Die, dwarf::DW_AT_decl_line, 0, Line);
+}
+
+/// addSourceLine - Add location information to specified debug information
+/// entry.
+void DwarfDebug::addSourceLine(DIE *Die, const DISubprogram *SP) {
+  // If there is no compile unit specified, don't add a line #.
+  if (SP->getCompileUnit().isNull())
+    return;
+  // If the line number is 0, don't add it.
+  if (SP->getLineNumber() == 0)
+    return;
+
+
+  unsigned Line = SP->getLineNumber();
+  unsigned FileID = findCompileUnit(SP->getCompileUnit())->getID();
+  assert(FileID && "Invalid file id");
+  addUInt(Die, dwarf::DW_AT_decl_file, 0, FileID);
+  addUInt(Die, dwarf::DW_AT_decl_line, 0, Line);
+}
+
+/// addSourceLine - Add location information to specified debug information
+/// entry.
+void DwarfDebug::addSourceLine(DIE *Die, const DIType *Ty) {
+  // If there is no compile unit specified, don't add a line #.
+  DICompileUnit CU = Ty->getCompileUnit();
+  if (CU.isNull())
+    return;
+
+  unsigned Line = Ty->getLineNumber();
+  unsigned FileID = findCompileUnit(CU)->getID();
+  assert(FileID && "Invalid file id");
+  addUInt(Die, dwarf::DW_AT_decl_file, 0, FileID);
+  addUInt(Die, dwarf::DW_AT_decl_line, 0, Line);
+}
+
+/// addSourceLine - Add location information to specified debug information
+/// entry.
+void DwarfDebug::addSourceLine(DIE *Die, const DINameSpace *NS) {
+  // If there is no compile unit specified, don't add a line #.
+  if (NS->getCompileUnit().isNull())
+    return;
+
+  unsigned Line = NS->getLineNumber();
+  StringRef FN = NS->getFilename();
+  StringRef Dir = NS->getDirectory();
+
+  unsigned FileID = GetOrCreateSourceID(Dir, FN);
+  assert(FileID && "Invalid file id");
+  addUInt(Die, dwarf::DW_AT_decl_file, 0, FileID);
+  addUInt(Die, dwarf::DW_AT_decl_line, 0, Line);
+}
+
+/* Byref variables, in Blocks, are declared by the programmer as
+   "SomeType VarName;", but the compiler creates a
+   __Block_byref_x_VarName struct, and gives the variable VarName
+   either the struct, or a pointer to the struct, as its type.  This
+   is necessary for various behind-the-scenes things the compiler
+   needs to do with by-reference variables in blocks.
+
+   However, as far as the original *programmer* is concerned, the
+   variable should still have type 'SomeType', as originally declared.
+
+   The following function dives into the __Block_byref_x_VarName
+   struct to find the original type of the variable.  This will be
+   passed back to the code generating the type for the Debug
+   Information Entry for the variable 'VarName'.  'VarName' will then
+   have the original type 'SomeType' in its debug information.
+
+   The original type 'SomeType' will be the type of the field named
+   'VarName' inside the __Block_byref_x_VarName struct.
+
+   NOTE: In order for this to not completely fail on the debugger
+   side, the Debug Information Entry for the variable VarName needs to
+   have a DW_AT_location that tells the debugger how to unwind through
+   the pointers and __Block_byref_x_VarName struct to find the actual
+   value of the variable.  The function addBlockByrefType does this.  */
+
+/// Find the type the programmer originally declared the variable to be
+/// and return that type.
+///
+DIType DwarfDebug::getBlockByrefType(DIType Ty, std::string Name) {
+
+  DIType subType = Ty;
+  unsigned tag = Ty.getTag();
+
+  if (tag == dwarf::DW_TAG_pointer_type) {
+    DIDerivedType DTy = DIDerivedType(Ty.getNode());
+    subType = DTy.getTypeDerivedFrom();
+  }
+
+  DICompositeType blockStruct = DICompositeType(subType.getNode());
+
+  DIArray Elements = blockStruct.getTypeArray();
+
+  if (Elements.isNull())
+    return Ty;
+
+  for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
+    DIDescriptor Element = Elements.getElement(i);
+    DIDerivedType DT = DIDerivedType(Element.getNode());
+    if (Name == DT.getName())
+      return (DT.getTypeDerivedFrom());
+  }
+
+  return Ty;
+}
+
+/// addComplexAddress - Start with the address based on the location provided,
+/// and generate the DWARF information necessary to find the actual variable
+/// given the extra address information encoded in the DIVariable, starting from
+/// the starting location.  Add the DWARF information to the die.
+///
+void DwarfDebug::addComplexAddress(DbgVariable *&DV, DIE *Die,
+                                   unsigned Attribute,
+                                   const MachineLocation &Location) {
+  const DIVariable &VD = DV->getVariable();
+  DIType Ty = VD.getType();
+
+  // Decode the original location, and use that as the start of the byref
+  // variable's location.
+  unsigned Reg = RI->getDwarfRegNum(Location.getReg(), false);
+  DIEBlock *Block = new DIEBlock();
+
+  if (Location.isReg()) {
+    if (Reg < 32) {
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_reg0 + Reg);
+    } else {
+      Reg = Reg - dwarf::DW_OP_reg0;
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_breg0 + Reg);
+      addUInt(Block, 0, dwarf::DW_FORM_udata, Reg);
+    }
+  } else {
+    if (Reg < 32)
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_breg0 + Reg);
+    else {
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_bregx);
+      addUInt(Block, 0, dwarf::DW_FORM_udata, Reg);
+    }
+
+    addUInt(Block, 0, dwarf::DW_FORM_sdata, Location.getOffset());
+  }
+
+  for (unsigned i = 0, N = VD.getNumAddrElements(); i < N; ++i) {
+    uint64_t Element = VD.getAddrElement(i);
+
+    if (Element == DIFactory::OpPlus) {
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
+      addUInt(Block, 0, dwarf::DW_FORM_udata, VD.getAddrElement(++i));
+    } else if (Element == DIFactory::OpDeref) {
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
+    } else llvm_unreachable("unknown DIFactory Opcode");
+  }
+
+  // Now attach the location information to the DIE.
+  addBlock(Die, Attribute, 0, Block);
+}
+
+/* Byref variables, in Blocks, are declared by the programmer as "SomeType
+   VarName;", but the compiler creates a __Block_byref_x_VarName struct, and
+   gives the variable VarName either the struct, or a pointer to the struct, as
+   its type.  This is necessary for various behind-the-scenes things the
+   compiler needs to do with by-reference variables in Blocks.
+
+   However, as far as the original *programmer* is concerned, the variable
+   should still have type 'SomeType', as originally declared.
+
+   The function getBlockByrefType dives into the __Block_byref_x_VarName
+   struct to find the original type of the variable, which is then assigned to
+   the variable's Debug Information Entry as its real type.  So far, so good.
+   However now the debugger will expect the variable VarName to have the type
+   SomeType.  So we need the location attribute for the variable to be an
+   expression that explains to the debugger how to navigate through the
+   pointers and struct to find the actual variable of type SomeType.
+
+   The following function does just that.  We start by getting
+   the "normal" location for the variable. This will be the location
+   of either the struct __Block_byref_x_VarName or the pointer to the
+   struct __Block_byref_x_VarName.
+
+   The struct will look something like:
+
+   struct __Block_byref_x_VarName {
+     ... <various fields>
+     struct __Block_byref_x_VarName *forwarding;
+     ... <various other fields>
+     SomeType VarName;
+     ... <maybe more fields>
+   };
+
+   If we are given the struct directly (as our starting point) we
+   need to tell the debugger to:
+
+   1).  Add the offset of the forwarding field.
+
+   2).  Follow that pointer to get the real __Block_byref_x_VarName
+   struct to use (the real one may have been copied onto the heap).
+
+   3).  Add the offset for the field VarName, to find the actual variable.
+
+   If we started with a pointer to the struct, then we need to
+   dereference that pointer first, before the other steps.
+   Translating this into DWARF ops, we will need to append the following
+   to the current location description for the variable:
+
+   DW_OP_deref                    -- optional, if we start with a pointer
+   DW_OP_plus_uconst <forward_fld_offset>
+   DW_OP_deref
+   DW_OP_plus_uconst <varName_fld_offset>
+
+   That is what this function does.  */
+
+/// addBlockByrefAddress - Start with the address based on the location
+/// provided, and generate the DWARF information necessary to find the
+/// actual Block variable (navigating the Block struct) based on the
+/// starting location.  Add the DWARF information to the die.  For
+/// more information, read large comment just above here.
+///
+void DwarfDebug::addBlockByrefAddress(DbgVariable *&DV, DIE *Die,
+                                      unsigned Attribute,
+                                      const MachineLocation &Location) {
+  const DIVariable &VD = DV->getVariable();
+  DIType Ty = VD.getType();
+  DIType TmpTy = Ty;
+  unsigned Tag = Ty.getTag();
+  bool isPointer = false;
+
+  StringRef varName = VD.getName();
+
+  if (Tag == dwarf::DW_TAG_pointer_type) {
+    DIDerivedType DTy = DIDerivedType(Ty.getNode());
+    TmpTy = DTy.getTypeDerivedFrom();
+    isPointer = true;
+  }
+
+  DICompositeType blockStruct = DICompositeType(TmpTy.getNode());
+
+  // Find the __forwarding field and the variable field in the __Block_byref
+  // struct.
+  DIArray Fields = blockStruct.getTypeArray();
+  DIDescriptor varField = DIDescriptor();
+  DIDescriptor forwardingField = DIDescriptor();
+
+
+  for (unsigned i = 0, N = Fields.getNumElements(); i < N; ++i) {
+    DIDescriptor Element = Fields.getElement(i);
+    DIDerivedType DT = DIDerivedType(Element.getNode());
+    StringRef fieldName = DT.getName();
+    if (fieldName == "__forwarding")
+      forwardingField = Element;
+    else if (fieldName == varName)
+      varField = Element;
+  }
+
+  assert(!varField.isNull() && "Can't find byref variable in Block struct");
+  assert(!forwardingField.isNull()
+         && "Can't find forwarding field in Block struct");
+
+  // Get the offsets for the forwarding field and the variable field.
+  unsigned int forwardingFieldOffset =
+    DIDerivedType(forwardingField.getNode()).getOffsetInBits() >> 3;
+  unsigned int varFieldOffset =
+    DIDerivedType(varField.getNode()).getOffsetInBits() >> 3;
+
+  // Decode the original location, and use that as the start of the byref
+  // variable's location.
+  unsigned Reg = RI->getDwarfRegNum(Location.getReg(), false);
+  DIEBlock *Block = new DIEBlock();
+
+  if (Location.isReg()) {
+    if (Reg < 32)
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_reg0 + Reg);
+    else {
+      Reg = Reg - dwarf::DW_OP_reg0;
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_breg0 + Reg);
+      addUInt(Block, 0, dwarf::DW_FORM_udata, Reg);
+    }
+  } else {
+    if (Reg < 32)
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_breg0 + Reg);
+    else {
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_bregx);
+      addUInt(Block, 0, dwarf::DW_FORM_udata, Reg);
+    }
+
+    addUInt(Block, 0, dwarf::DW_FORM_sdata, Location.getOffset());
+  }
+
+  // If we started with a pointer to the __Block_byref... struct, then
+  // the first thing we need to do is dereference the pointer (DW_OP_deref).
+  if (isPointer)
+    addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
+
+  // Next add the offset for the '__forwarding' field:
+  // DW_OP_plus_uconst ForwardingFieldOffset.  Note there's no point in
+  // adding the offset if it's 0.
+  if (forwardingFieldOffset > 0) {
+    addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
+    addUInt(Block, 0, dwarf::DW_FORM_udata, forwardingFieldOffset);
+  }
+
+  // Now dereference the __forwarding field to get to the real __Block_byref
+  // struct:  DW_OP_deref.
+  addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
+
+  // Now that we've got the real __Block_byref... struct, add the offset
+  // for the variable's field to get to the location of the actual variable:
+  // DW_OP_plus_uconst varFieldOffset.  Again, don't add if it's 0.
+  if (varFieldOffset > 0) {
+    addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
+    addUInt(Block, 0, dwarf::DW_FORM_udata, varFieldOffset);
+  }
+
+  // Now attach the location information to the DIE.
+  addBlock(Die, Attribute, 0, Block);
+}
+
+/// addAddress - Add an address attribute to a die based on the location
+/// provided.
+void DwarfDebug::addAddress(DIE *Die, unsigned Attribute,
+                            const MachineLocation &Location) {
+  unsigned Reg = RI->getDwarfRegNum(Location.getReg(), false);
+  DIEBlock *Block = new DIEBlock();
+
+  if (Location.isReg()) {
+    if (Reg < 32) {
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_reg0 + Reg);
+    } else {
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_regx);
+      addUInt(Block, 0, dwarf::DW_FORM_udata, Reg);
+    }
+  } else {
+    if (Reg < 32) {
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_breg0 + Reg);
+    } else {
+      addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_bregx);
+      addUInt(Block, 0, dwarf::DW_FORM_udata, Reg);
+    }
+
+    addUInt(Block, 0, dwarf::DW_FORM_sdata, Location.getOffset());
+  }
+
+  addBlock(Die, Attribute, 0, Block);
+}
+
+/// addToContextOwner - Add Die into the list of its context owner's children.
+void DwarfDebug::addToContextOwner(DIE *Die, DIDescriptor Context) {
+  if (Context.isNull())
+    ModuleCU->addDie(Die);
+  else if (Context.isType()) {
+    DIE *ContextDIE = getOrCreateTypeDIE(DIType(Context.getNode()));
+    ContextDIE->addChild(Die);
+  } else if (Context.isNameSpace()) {
+    DIE *ContextDIE = getOrCreateNameSpace(DINameSpace(Context.getNode()));
+    ContextDIE->addChild(Die);
+  } else if (DIE *ContextDIE = ModuleCU->getDIE(Context.getNode()))
+    ContextDIE->addChild(Die);
+  else 
+    ModuleCU->addDie(Die);
+}
+
+/// getOrCreateTypeDIE - Find existing DIE or create new DIE for the
+/// given DIType.
+DIE *DwarfDebug::getOrCreateTypeDIE(DIType Ty) {
+  DIE *TyDIE = ModuleCU->getDIE(Ty.getNode());
+  if (TyDIE)
+    return TyDIE;
+
+  // Create new type.
+  TyDIE = new DIE(dwarf::DW_TAG_base_type);
+  ModuleCU->insertDIE(Ty.getNode(), TyDIE);
+  if (Ty.isBasicType())
+    constructTypeDIE(*TyDIE, DIBasicType(Ty.getNode()));
+  else if (Ty.isCompositeType())
+    constructTypeDIE(*TyDIE, DICompositeType(Ty.getNode()));
+  else {
+    assert(Ty.isDerivedType() && "Unknown kind of DIType");
+    constructTypeDIE(*TyDIE, DIDerivedType(Ty.getNode()));
+  }
+
+  addToContextOwner(TyDIE, Ty.getContext());
+  return TyDIE;
+}
+
+/// addType - Add a new type attribute to the specified entity.
+void DwarfDebug::addType(DIE *Entity, DIType Ty) {
+  if (Ty.isNull())
+    return;
+
+  // Check for pre-existence.
+  DIEEntry *Entry = ModuleCU->getDIEEntry(Ty.getNode());
+  // If it exists then use the existing value.
+  if (Entry) {
+    Entity->addValue(dwarf::DW_AT_type, dwarf::DW_FORM_ref4, Entry);
+    return;
+  }
+
+  // Set up proxy.
+  Entry = createDIEEntry();
+  ModuleCU->insertDIEEntry(Ty.getNode(), Entry);
+
+  // Construct type.
+  DIE *Buffer = getOrCreateTypeDIE(Ty);
+
+  Entry->setEntry(Buffer);
+  Entity->addValue(dwarf::DW_AT_type, dwarf::DW_FORM_ref4, Entry);
+}
+
+/// constructTypeDIE - Construct basic type die from DIBasicType.
+void DwarfDebug::constructTypeDIE(DIE &Buffer, DIBasicType BTy) {
+  // Get core information.
+  StringRef Name = BTy.getName();
+  Buffer.setTag(dwarf::DW_TAG_base_type);
+  addUInt(&Buffer, dwarf::DW_AT_encoding,  dwarf::DW_FORM_data1,
+          BTy.getEncoding());
+
+  // Add name if not anonymous or intermediate type.
+  if (!Name.empty())
+    addString(&Buffer, dwarf::DW_AT_name, dwarf::DW_FORM_string, Name);
+  uint64_t Size = BTy.getSizeInBits() >> 3;
+  addUInt(&Buffer, dwarf::DW_AT_byte_size, 0, Size);
+}
+
+/// constructTypeDIE - Construct derived type die from DIDerivedType.
+void DwarfDebug::constructTypeDIE(DIE &Buffer, DIDerivedType DTy) {
+  // Get core information.
+  StringRef Name = DTy.getName();
+  uint64_t Size = DTy.getSizeInBits() >> 3;
+  unsigned Tag = DTy.getTag();
+
+  // FIXME - Workaround for templates.
+  if (Tag == dwarf::DW_TAG_inheritance) Tag = dwarf::DW_TAG_reference_type;
+
+  Buffer.setTag(Tag);
+
+  // Map to main type, void will not have a type.
+  DIType FromTy = DTy.getTypeDerivedFrom();
+  addType(&Buffer, FromTy);
+
+  // Add name if not anonymous or intermediate type.
+  if (!Name.empty())
+    addString(&Buffer, dwarf::DW_AT_name, dwarf::DW_FORM_string, Name);
+
+  // Add size if non-zero (derived types might be zero-sized.)
+  if (Size)
+    addUInt(&Buffer, dwarf::DW_AT_byte_size, 0, Size);
+
+  // Add source line info if available and TyDesc is not a forward declaration.
+  if (!DTy.isForwardDecl())
+    addSourceLine(&Buffer, &DTy);
+}
+
+/// constructTypeDIE - Construct type DIE from DICompositeType.
+void DwarfDebug::constructTypeDIE(DIE &Buffer, DICompositeType CTy) {
+  // Get core information.
+  StringRef Name = CTy.getName();
+
+  uint64_t Size = CTy.getSizeInBits() >> 3;
+  unsigned Tag = CTy.getTag();
+  Buffer.setTag(Tag);
+
+  switch (Tag) {
+  case dwarf::DW_TAG_vector_type:
+  case dwarf::DW_TAG_array_type:
+    constructArrayTypeDIE(Buffer, &CTy);
+    break;
+  case dwarf::DW_TAG_enumeration_type: {
+    DIArray Elements = CTy.getTypeArray();
+
+    // Add enumerators to enumeration type.
+    for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
+      DIE *ElemDie = NULL;
+      DIEnumerator Enum(Elements.getElement(i).getNode());
+      if (!Enum.isNull()) {
+        ElemDie = constructEnumTypeDIE(&Enum);
+        Buffer.addChild(ElemDie);
+      }
+    }
+  }
+    break;
+  case dwarf::DW_TAG_subroutine_type: {
+    // Add return type.
+    DIArray Elements = CTy.getTypeArray();
+    DIDescriptor RTy = Elements.getElement(0);
+    addType(&Buffer, DIType(RTy.getNode()));
+
+    // Add prototype flag.
+    addUInt(&Buffer, dwarf::DW_AT_prototyped, dwarf::DW_FORM_flag, 1);
+
+    // Add arguments.
+    for (unsigned i = 1, N = Elements.getNumElements(); i < N; ++i) {
+      DIE *Arg = new DIE(dwarf::DW_TAG_formal_parameter);
+      DIDescriptor Ty = Elements.getElement(i);
+      addType(Arg, DIType(Ty.getNode()));
+      Buffer.addChild(Arg);
+    }
+  }
+    break;
+  case dwarf::DW_TAG_structure_type:
+  case dwarf::DW_TAG_union_type:
+  case dwarf::DW_TAG_class_type: {
+    // Add elements to structure type.
+    DIArray Elements = CTy.getTypeArray();
+
+    // A forward struct declared type may not have elements available.
+    if (Elements.isNull())
+      break;
+
+    // Add elements to structure type.
+    for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
+      DIDescriptor Element = Elements.getElement(i);
+      if (Element.isNull())
+        continue;
+      DIE *ElemDie = NULL;
+      if (Element.getTag() == dwarf::DW_TAG_subprogram)
+        ElemDie = createSubprogramDIE(DISubprogram(Element.getNode()));
+      else if (Element.getTag() == dwarf::DW_TAG_auto_variable) {
+        DIVariable DV(Element.getNode());
+        ElemDie = new DIE(dwarf::DW_TAG_variable);
+        addString(ElemDie, dwarf::DW_AT_name, dwarf::DW_FORM_string,
+                  DV.getName());
+        addType(ElemDie, DV.getType());
+        addUInt(ElemDie, dwarf::DW_AT_declaration, dwarf::DW_FORM_flag, 1);
+        addUInt(ElemDie, dwarf::DW_AT_external, dwarf::DW_FORM_flag, 1);
+        addSourceLine(ElemDie, &DV);
+      } else
+        ElemDie = createMemberDIE(DIDerivedType(Element.getNode()));
+      Buffer.addChild(ElemDie);
+    }
+
+    if (CTy.isAppleBlockExtension())
+      addUInt(&Buffer, dwarf::DW_AT_APPLE_block, dwarf::DW_FORM_flag, 1);
+
+    unsigned RLang = CTy.getRunTimeLang();
+    if (RLang)
+      addUInt(&Buffer, dwarf::DW_AT_APPLE_runtime_class,
+              dwarf::DW_FORM_data1, RLang);
+
+    DICompositeType ContainingType = CTy.getContainingType();
+    if (!ContainingType.isNull())
+      addDIEEntry(&Buffer, dwarf::DW_AT_containing_type, dwarf::DW_FORM_ref4, 
+                  getOrCreateTypeDIE(DIType(ContainingType.getNode())));
+    break;
+  }
+  default:
+    break;
+  }
+
+  // Add name if not anonymous or intermediate type.
+  if (!Name.empty())
+    addString(&Buffer, dwarf::DW_AT_name, dwarf::DW_FORM_string, Name);
+
+  if (Tag == dwarf::DW_TAG_enumeration_type || Tag == dwarf::DW_TAG_class_type ||
+      Tag == dwarf::DW_TAG_structure_type || Tag == dwarf::DW_TAG_union_type) {
+    // Add size if non-zero (derived types might be zero-sized.)
+    if (Size)
+      addUInt(&Buffer, dwarf::DW_AT_byte_size, 0, Size);
+    else {
+      // Add zero size if it is not a forward declaration.
+      if (CTy.isForwardDecl())
+        addUInt(&Buffer, dwarf::DW_AT_declaration, dwarf::DW_FORM_flag, 1);
+      else
+        addUInt(&Buffer, dwarf::DW_AT_byte_size, 0, 0);
+    }
+
+    // Add source line info if available.
+    if (!CTy.isForwardDecl())
+      addSourceLine(&Buffer, &CTy);
+  }
+}
+
+/// constructSubrangeDIE - Construct subrange DIE from DISubrange.
+void DwarfDebug::constructSubrangeDIE(DIE &Buffer, DISubrange SR, DIE *IndexTy){
+  int64_t L = SR.getLo();
+  int64_t H = SR.getHi();
+  DIE *DW_Subrange = new DIE(dwarf::DW_TAG_subrange_type);
+
+  addDIEEntry(DW_Subrange, dwarf::DW_AT_type, dwarf::DW_FORM_ref4, IndexTy);
+  if (L)
+    addSInt(DW_Subrange, dwarf::DW_AT_lower_bound, 0, L);
+  addSInt(DW_Subrange, dwarf::DW_AT_upper_bound, 0, H);
+
+  Buffer.addChild(DW_Subrange);
+}
+
+/// constructArrayTypeDIE - Construct array type DIE from DICompositeType.
+void DwarfDebug::constructArrayTypeDIE(DIE &Buffer,
+                                       DICompositeType *CTy) {
+  Buffer.setTag(dwarf::DW_TAG_array_type);
+  if (CTy->getTag() == dwarf::DW_TAG_vector_type)
+    addUInt(&Buffer, dwarf::DW_AT_GNU_vector, dwarf::DW_FORM_flag, 1);
+
+  // Emit derived type.
+  addType(&Buffer, CTy->getTypeDerivedFrom());
+  DIArray Elements = CTy->getTypeArray();
+
+  // Get an anonymous type for index type.
+  DIE *IdxTy = ModuleCU->getIndexTyDie();
+  if (!IdxTy) {
+    // Construct an anonymous type for index type.
+    IdxTy = new DIE(dwarf::DW_TAG_base_type);
+    addUInt(IdxTy, dwarf::DW_AT_byte_size, 0, sizeof(int32_t));
+    addUInt(IdxTy, dwarf::DW_AT_encoding, dwarf::DW_FORM_data1,
+            dwarf::DW_ATE_signed);
+    ModuleCU->addDie(IdxTy);
+    ModuleCU->setIndexTyDie(IdxTy);
+  }
+
+  // Add subranges to array type.
+  for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
+    DIDescriptor Element = Elements.getElement(i);
+    if (Element.getTag() == dwarf::DW_TAG_subrange_type)
+      constructSubrangeDIE(Buffer, DISubrange(Element.getNode()), IdxTy);
+  }
+}
+
+/// constructEnumTypeDIE - Construct enum type DIE from DIEnumerator.
+DIE *DwarfDebug::constructEnumTypeDIE(DIEnumerator *ETy) {
+  DIE *Enumerator = new DIE(dwarf::DW_TAG_enumerator);
+  StringRef Name = ETy->getName();
+  addString(Enumerator, dwarf::DW_AT_name, dwarf::DW_FORM_string, Name);
+  int64_t Value = ETy->getEnumValue();
+  addSInt(Enumerator, dwarf::DW_AT_const_value, dwarf::DW_FORM_sdata, Value);
+  return Enumerator;
+}
+
+/// getRealLinkageName - If special LLVM prefix that is used to inform the asm 
+/// printer to not emit usual symbol prefix before the symbol name is used then
+/// return linkage name after skipping this special LLVM prefix.
+static StringRef getRealLinkageName(StringRef LinkageName) {
+  char One = '\1';
+  if (LinkageName.startswith(StringRef(&One, 1)))
+    return LinkageName.substr(1);
+  return LinkageName;
+}
+
+/// createGlobalVariableDIE - Create new DIE using GV.
+DIE *DwarfDebug::createGlobalVariableDIE(const DIGlobalVariable &GV) {
+  // If the global variable was optmized out then no need to create debug info
+  // entry.
+  if (!GV.getGlobal()) return NULL;
+  if (GV.getDisplayName().empty()) return NULL;
+
+  DIE *GVDie = new DIE(dwarf::DW_TAG_variable);
+  addString(GVDie, dwarf::DW_AT_name, dwarf::DW_FORM_string,
+            GV.getDisplayName());
+
+  StringRef LinkageName = GV.getLinkageName();
+  if (!LinkageName.empty())
+    addString(GVDie, dwarf::DW_AT_MIPS_linkage_name, dwarf::DW_FORM_string,
+              getRealLinkageName(LinkageName));
+
+  addType(GVDie, GV.getType());
+  if (!GV.isLocalToUnit())
+    addUInt(GVDie, dwarf::DW_AT_external, dwarf::DW_FORM_flag, 1);
+  addSourceLine(GVDie, &GV);
+
+  return GVDie;
+}
+
+/// createMemberDIE - Create new member DIE.
+DIE *DwarfDebug::createMemberDIE(const DIDerivedType &DT) {
+  DIE *MemberDie = new DIE(DT.getTag());
+  StringRef Name = DT.getName();
+  if (!Name.empty())
+    addString(MemberDie, dwarf::DW_AT_name, dwarf::DW_FORM_string, Name);
+  
+  addType(MemberDie, DT.getTypeDerivedFrom());
+
+  addSourceLine(MemberDie, &DT);
+
+  DIEBlock *MemLocationDie = new DIEBlock();
+  addUInt(MemLocationDie, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_plus_uconst);
+
+  uint64_t Size = DT.getSizeInBits();
+  uint64_t FieldSize = DT.getOriginalTypeSize();
+
+  if (Size != FieldSize) {
+    // Handle bitfield.
+    addUInt(MemberDie, dwarf::DW_AT_byte_size, 0, DT.getOriginalTypeSize()>>3);
+    addUInt(MemberDie, dwarf::DW_AT_bit_size, 0, DT.getSizeInBits());
+
+    uint64_t Offset = DT.getOffsetInBits();
+    uint64_t AlignMask = ~(DT.getAlignInBits() - 1);
+    uint64_t HiMark = (Offset + FieldSize) & AlignMask;
+    uint64_t FieldOffset = (HiMark - FieldSize);
+    Offset -= FieldOffset;
+
+    // Maybe we need to work from the other end.
+    if (TD->isLittleEndian()) Offset = FieldSize - (Offset + Size);
+    addUInt(MemberDie, dwarf::DW_AT_bit_offset, 0, Offset);
+
+    // Here WD_AT_data_member_location points to the anonymous
+    // field that includes this bit field.
+    addUInt(MemLocationDie, 0, dwarf::DW_FORM_udata, FieldOffset >> 3);
+
+  } else
+    // This is not a bitfield.
+    addUInt(MemLocationDie, 0, dwarf::DW_FORM_udata, DT.getOffsetInBits() >> 3);
+
+  if (DT.getTag() == dwarf::DW_TAG_inheritance
+      && DT.isVirtual()) {
+
+    // For C++, virtual base classes are not at fixed offset. Use following
+    // expression to extract appropriate offset from vtable.
+    // BaseAddr = ObAddr + *((*ObAddr) - Offset)
+
+    DIEBlock *VBaseLocationDie = new DIEBlock();
+    addUInt(VBaseLocationDie, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_dup);
+    addUInt(VBaseLocationDie, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
+    addUInt(VBaseLocationDie, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
+    addUInt(VBaseLocationDie, 0, dwarf::DW_FORM_udata, DT.getOffsetInBits());
+    addUInt(VBaseLocationDie, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_minus);
+    addUInt(VBaseLocationDie, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_deref);
+    addUInt(VBaseLocationDie, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
+
+    addBlock(MemberDie, dwarf::DW_AT_data_member_location, 0, 
+             VBaseLocationDie);
+  } else
+    addBlock(MemberDie, dwarf::DW_AT_data_member_location, 0, MemLocationDie);
+
+  if (DT.isProtected())
+    addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_flag,
+            dwarf::DW_ACCESS_protected);
+  else if (DT.isPrivate())
+    addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_flag,
+            dwarf::DW_ACCESS_private);
+  else if (DT.getTag() == dwarf::DW_TAG_inheritance)
+    addUInt(MemberDie, dwarf::DW_AT_accessibility, dwarf::DW_FORM_flag,
+            dwarf::DW_ACCESS_public);
+  if (DT.isVirtual())
+    addUInt(MemberDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_flag,
+            dwarf::DW_VIRTUALITY_virtual);
+  return MemberDie;
+}
+
+/// createSubprogramDIE - Create new DIE using SP.
+DIE *DwarfDebug::createSubprogramDIE(const DISubprogram &SP, bool MakeDecl) {
+  DIE *SPDie = ModuleCU->getDIE(SP.getNode());
+  if (SPDie)
+    return SPDie;
+
+  SPDie = new DIE(dwarf::DW_TAG_subprogram);
+  addString(SPDie, dwarf::DW_AT_name, dwarf::DW_FORM_string, SP.getName());
+
+  StringRef LinkageName = SP.getLinkageName();
+  if (!LinkageName.empty())
+    addString(SPDie, dwarf::DW_AT_MIPS_linkage_name, dwarf::DW_FORM_string,
+              getRealLinkageName(LinkageName));
+
+  addSourceLine(SPDie, &SP);
+
+  // Add prototyped tag, if C or ObjC.
+  unsigned Lang = SP.getCompileUnit().getLanguage();
+  if (Lang == dwarf::DW_LANG_C99 || Lang == dwarf::DW_LANG_C89 ||
+      Lang == dwarf::DW_LANG_ObjC)
+    addUInt(SPDie, dwarf::DW_AT_prototyped, dwarf::DW_FORM_flag, 1);
+
+  // Add Return Type.
+  DICompositeType SPTy = SP.getType();
+  DIArray Args = SPTy.getTypeArray();
+  unsigned SPTag = SPTy.getTag();
+
+  if (Args.isNull() || SPTag != dwarf::DW_TAG_subroutine_type)
+    addType(SPDie, SPTy);
+  else
+    addType(SPDie, DIType(Args.getElement(0).getNode()));
+
+  unsigned VK = SP.getVirtuality();
+  if (VK) {
+    addUInt(SPDie, dwarf::DW_AT_virtuality, dwarf::DW_FORM_flag, VK);
+    DIEBlock *Block = new DIEBlock();
+    addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
+    addUInt(Block, 0, dwarf::DW_FORM_data1, SP.getVirtualIndex());
+    addBlock(SPDie, dwarf::DW_AT_vtable_elem_location, 0, Block);
+    ContainingTypeMap.insert(std::make_pair(SPDie, 
+                                            SP.getContainingType().getNode()));
+  }
+
+  if (MakeDecl || !SP.isDefinition()) {
+    addUInt(SPDie, dwarf::DW_AT_declaration, dwarf::DW_FORM_flag, 1);
+
+    // Add arguments. Do not add arguments for subprogram definition. They will
+    // be handled while processing variables.
+    DICompositeType SPTy = SP.getType();
+    DIArray Args = SPTy.getTypeArray();
+    unsigned SPTag = SPTy.getTag();
+
+    if (SPTag == dwarf::DW_TAG_subroutine_type)
+      for (unsigned i = 1, N =  Args.getNumElements(); i < N; ++i) {
+        DIE *Arg = new DIE(dwarf::DW_TAG_formal_parameter);
+        DIType ATy = DIType(DIType(Args.getElement(i).getNode()));
+        addType(Arg, ATy);
+        if (ATy.isArtificial())
+          addUInt(Arg, dwarf::DW_AT_artificial, dwarf::DW_FORM_flag, 1);
+        SPDie->addChild(Arg);
+      }
+  }
+
+  if (SP.isArtificial())
+    addUInt(SPDie, dwarf::DW_AT_artificial, dwarf::DW_FORM_flag, 1);
+
+  // DW_TAG_inlined_subroutine may refer to this DIE.
+  ModuleCU->insertDIE(SP.getNode(), SPDie);
+  return SPDie;
+}
+
+/// findCompileUnit - Get the compile unit for the given descriptor.
+///
+CompileUnit *DwarfDebug::findCompileUnit(DICompileUnit Unit) {
+  DenseMap<Value *, CompileUnit *>::const_iterator I =
+    CompileUnitMap.find(Unit.getNode());
+  if (I == CompileUnitMap.end())
+    return constructCompileUnit(Unit.getNode());
+  return I->second;
+}
+
+/// getUpdatedDbgScope - Find or create DbgScope assicated with the instruction.
+/// Initialize scope and update scope hierarchy.
+DbgScope *DwarfDebug::getUpdatedDbgScope(MDNode *N, const MachineInstr *MI,
+  MDNode *InlinedAt) {
+  assert (N && "Invalid Scope encoding!");
+  assert (MI && "Missing machine instruction!");
+  bool GetConcreteScope = (MI && InlinedAt);
+
+  DbgScope *NScope = NULL;
+
+  if (InlinedAt)
+    NScope = DbgScopeMap.lookup(InlinedAt);
+  else
+    NScope = DbgScopeMap.lookup(N);
+  assert (NScope && "Unable to find working scope!");
+
+  if (NScope->getFirstInsn())
+    return NScope;
+
+  DbgScope *Parent = NULL;
+  if (GetConcreteScope) {
+    DILocation IL(InlinedAt);
+    Parent = getUpdatedDbgScope(IL.getScope().getNode(), MI,
+                         IL.getOrigLocation().getNode());
+    assert (Parent && "Unable to find Parent scope!");
+    NScope->setParent(Parent);
+    Parent->addScope(NScope);
+  } else if (DIDescriptor(N).isLexicalBlock()) {
+    DILexicalBlock DB(N);
+    if (!DB.getContext().isNull()) {
+      Parent = getUpdatedDbgScope(DB.getContext().getNode(), MI, InlinedAt);
+      NScope->setParent(Parent);
+      Parent->addScope(NScope);
+    }
+  }
+
+  NScope->setFirstInsn(MI);
+
+  if (!Parent && !InlinedAt) {
+    StringRef SPName = DISubprogram(N).getLinkageName();
+    if (SPName == MF->getFunction()->getName())
+      CurrentFnDbgScope = NScope;
+  }
+
+  if (GetConcreteScope) {
+    ConcreteScopes[InlinedAt] = NScope;
+    getOrCreateAbstractScope(N);
+  }
+
+  return NScope;
+}
+
+DbgScope *DwarfDebug::getOrCreateAbstractScope(MDNode *N) {
+  assert (N && "Invalid Scope encoding!");
+
+  DbgScope *AScope = AbstractScopes.lookup(N);
+  if (AScope)
+    return AScope;
+
+  DbgScope *Parent = NULL;
+
+  DIDescriptor Scope(N);
+  if (Scope.isLexicalBlock()) {
+    DILexicalBlock DB(N);
+    DIDescriptor ParentDesc = DB.getContext();
+    if (!ParentDesc.isNull())
+      Parent = getOrCreateAbstractScope(ParentDesc.getNode());
+  }
+
+  AScope = new DbgScope(Parent, DIDescriptor(N), NULL);
+
+  if (Parent)
+    Parent->addScope(AScope);
+  AScope->setAbstractScope();
+  AbstractScopes[N] = AScope;
+  if (DIDescriptor(N).isSubprogram())
+    AbstractScopesList.push_back(AScope);
+  return AScope;
+}
+
+/// updateSubprogramScopeDIE - Find DIE for the given subprogram and
+/// attach appropriate DW_AT_low_pc and DW_AT_high_pc attributes.
+/// If there are global variables in this scope then create and insert
+/// DIEs for these variables.
+DIE *DwarfDebug::updateSubprogramScopeDIE(MDNode *SPNode) {
+
+ DIE *SPDie = ModuleCU->getDIE(SPNode);
+ assert (SPDie && "Unable to find subprogram DIE!");
+ DISubprogram SP(SPNode);
+ // There is not any need to generate specification DIE for a function
+ // defined at compile unit level. If a function is defined inside another
+ // function then gdb prefers the definition at top level and but does not
+ // expect specification DIE in parent function. So avoid creating 
+ // specification DIE for a function defined inside a function.
+ if (SP.isDefinition() && !SP.getContext().isCompileUnit()
+     && !SP.getContext().isSubprogram()) {
+   addUInt(SPDie, dwarf::DW_AT_declaration, dwarf::DW_FORM_flag, 1);
+  // Add arguments. 
+   DICompositeType SPTy = SP.getType();
+   DIArray Args = SPTy.getTypeArray();
+   unsigned SPTag = SPTy.getTag();
+   if (SPTag == dwarf::DW_TAG_subroutine_type)
+     for (unsigned i = 1, N =  Args.getNumElements(); i < N; ++i) {
+       DIE *Arg = new DIE(dwarf::DW_TAG_formal_parameter);
+       DIType ATy = DIType(DIType(Args.getElement(i).getNode()));
+       addType(Arg, ATy);
+       if (ATy.isArtificial())
+         addUInt(Arg, dwarf::DW_AT_artificial, dwarf::DW_FORM_flag, 1);
+       SPDie->addChild(Arg);
+     }
+   DIE *SPDeclDie = SPDie;
+   SPDie = new DIE(dwarf::DW_TAG_subprogram);
+   addDIEEntry(SPDie, dwarf::DW_AT_specification, dwarf::DW_FORM_ref4, 
+               SPDeclDie);
+   ModuleCU->addDie(SPDie);
+ }
+
+ addLabel(SPDie, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
+          DWLabel("func_begin", SubprogramCount));
+ addLabel(SPDie, dwarf::DW_AT_high_pc, dwarf::DW_FORM_addr,
+          DWLabel("func_end", SubprogramCount));
+ MachineLocation Location(RI->getFrameRegister(*MF));
+ addAddress(SPDie, dwarf::DW_AT_frame_base, Location);
+
+ if (!DISubprogram(SPNode).isLocalToUnit())
+   addUInt(SPDie, dwarf::DW_AT_external, dwarf::DW_FORM_flag, 1);
+
+ return SPDie;
+}
+
+/// constructLexicalScope - Construct new DW_TAG_lexical_block
+/// for this scope and attach DW_AT_low_pc/DW_AT_high_pc labels.
+DIE *DwarfDebug::constructLexicalScopeDIE(DbgScope *Scope) {
+  unsigned StartID = MMI->MappedLabel(Scope->getStartLabelID());
+  unsigned EndID = MMI->MappedLabel(Scope->getEndLabelID());
+
+  // Ignore empty scopes.
+  if (StartID == EndID && StartID != 0)
+    return NULL;
+
+  DIE *ScopeDIE = new DIE(dwarf::DW_TAG_lexical_block);
+  if (Scope->isAbstractScope())
+    return ScopeDIE;
+
+  addLabel(ScopeDIE, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
+           StartID ?
+             DWLabel("label", StartID)
+           : DWLabel("func_begin", SubprogramCount));
+  addLabel(ScopeDIE, dwarf::DW_AT_high_pc, dwarf::DW_FORM_addr,
+           EndID ?
+             DWLabel("label", EndID)
+           : DWLabel("func_end", SubprogramCount));
+
+
+
+  return ScopeDIE;
+}
+
+/// constructInlinedScopeDIE - This scope represents inlined body of
+/// a function. Construct DIE to represent this concrete inlined copy
+/// of the function.
+DIE *DwarfDebug::constructInlinedScopeDIE(DbgScope *Scope) {
+  unsigned StartID = MMI->MappedLabel(Scope->getStartLabelID());
+  unsigned EndID = MMI->MappedLabel(Scope->getEndLabelID());
+  assert (StartID && "Invalid starting label for an inlined scope!");
+  assert (EndID && "Invalid end label for an inlined scope!");
+  // Ignore empty scopes.
+  if (StartID == EndID && StartID != 0)
+    return NULL;
+
+  DIScope DS(Scope->getScopeNode());
+  if (DS.isNull())
+    return NULL;
+  DIE *ScopeDIE = new DIE(dwarf::DW_TAG_inlined_subroutine);
+
+  DISubprogram InlinedSP = getDISubprogram(DS.getNode());
+  DIE *OriginDIE = ModuleCU->getDIE(InlinedSP.getNode());
+  assert (OriginDIE && "Unable to find Origin DIE!");
+  addDIEEntry(ScopeDIE, dwarf::DW_AT_abstract_origin,
+              dwarf::DW_FORM_ref4, OriginDIE);
+
+  addLabel(ScopeDIE, dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
+           DWLabel("label", StartID));
+  addLabel(ScopeDIE, dwarf::DW_AT_high_pc, dwarf::DW_FORM_addr,
+           DWLabel("label", EndID));
+
+  InlinedSubprogramDIEs.insert(OriginDIE);
+
+  // Track the start label for this inlined function.
+  DenseMap<MDNode *, SmallVector<InlineInfoLabels, 4> >::iterator
+    I = InlineInfo.find(InlinedSP.getNode());
+
+  if (I == InlineInfo.end()) {
+    InlineInfo[InlinedSP.getNode()].push_back(std::make_pair(StartID,
+                                                             ScopeDIE));
+    InlinedSPNodes.push_back(InlinedSP.getNode());
+  } else
+    I->second.push_back(std::make_pair(StartID, ScopeDIE));
+
+  StringPool.insert(InlinedSP.getName());
+  StringPool.insert(getRealLinkageName(InlinedSP.getLinkageName()));
+
+  DILocation DL(Scope->getInlinedAt());
+  addUInt(ScopeDIE, dwarf::DW_AT_call_file, 0, ModuleCU->getID());
+  addUInt(ScopeDIE, dwarf::DW_AT_call_line, 0, DL.getLineNumber());
+
+  return ScopeDIE;
+}
+
+
+/// constructVariableDIE - Construct a DIE for the given DbgVariable.
+DIE *DwarfDebug::constructVariableDIE(DbgVariable *DV, DbgScope *Scope) {
+  // Get the descriptor.
+  const DIVariable &VD = DV->getVariable();
+  StringRef Name = VD.getName();
+  if (Name.empty())
+    return NULL;
+
+  // Translate tag to proper Dwarf tag.  The result variable is dropped for
+  // now.
+  unsigned Tag;
+  switch (VD.getTag()) {
+  case dwarf::DW_TAG_return_variable:
+    return NULL;
+  case dwarf::DW_TAG_arg_variable:
+    Tag = dwarf::DW_TAG_formal_parameter;
+    break;
+  case dwarf::DW_TAG_auto_variable:    // fall thru
+  default:
+    Tag = dwarf::DW_TAG_variable;
+    break;
+  }
+
+  // Define variable debug information entry.
+  DIE *VariableDie = new DIE(Tag);
+
+
+  DIE *AbsDIE = NULL;
+  if (DbgVariable *AV = DV->getAbstractVariable())
+    AbsDIE = AV->getDIE();
+
+  if (AbsDIE) {
+    DIScope DS(Scope->getScopeNode());
+    DISubprogram InlinedSP = getDISubprogram(DS.getNode());
+    DIE *OriginSPDIE = ModuleCU->getDIE(InlinedSP.getNode());
+    (void) OriginSPDIE;
+    assert (OriginSPDIE && "Unable to find Origin DIE for the SP!");
+    DIE *AbsDIE = DV->getAbstractVariable()->getDIE();
+    assert (AbsDIE && "Unable to find Origin DIE for the Variable!");
+    addDIEEntry(VariableDie, dwarf::DW_AT_abstract_origin,
+                dwarf::DW_FORM_ref4, AbsDIE);
+  }
+  else {
+    addString(VariableDie, dwarf::DW_AT_name, dwarf::DW_FORM_string, Name);
+    addSourceLine(VariableDie, &VD);
+
+    // Add variable type.
+    // FIXME: isBlockByrefVariable should be reformulated in terms of complex
+    // addresses instead.
+    if (VD.isBlockByrefVariable())
+      addType(VariableDie, getBlockByrefType(VD.getType(), Name));
+    else
+      addType(VariableDie, VD.getType());
+  }
+
+  // Add variable address.
+  if (!Scope->isAbstractScope()) {
+    MachineLocation Location;
+    unsigned FrameReg;
+    int Offset = RI->getFrameIndexReference(*MF, DV->getFrameIndex(), FrameReg);
+    Location.set(FrameReg, Offset);
+
+    if (VD.hasComplexAddress())
+      addComplexAddress(DV, VariableDie, dwarf::DW_AT_location, Location);
+    else if (VD.isBlockByrefVariable())
+      addBlockByrefAddress(DV, VariableDie, dwarf::DW_AT_location, Location);
+    else
+      addAddress(VariableDie, dwarf::DW_AT_location, Location);
+  }
+
+  if (Tag == dwarf::DW_TAG_formal_parameter && VD.getType().isArtificial())
+    addUInt(VariableDie, dwarf::DW_AT_artificial, dwarf::DW_FORM_flag, 1);
+  DV->setDIE(VariableDie);
+  return VariableDie;
+
+}
+
+void DwarfDebug::addPubTypes(DISubprogram SP) {
+  DICompositeType SPTy = SP.getType();
+  unsigned SPTag = SPTy.getTag();
+  if (SPTag != dwarf::DW_TAG_subroutine_type) 
+    return;
+
+  DIArray Args = SPTy.getTypeArray();
+  if (Args.isNull()) 
+    return;
+
+  for (unsigned i = 0, e = Args.getNumElements(); i != e; ++i) {
+    DIType ATy(Args.getElement(i).getNode());
+    if (ATy.isNull())
+      continue;
+    DICompositeType CATy = getDICompositeType(ATy);
+    if (!CATy.isNull() && !CATy.getName().empty()) {
+      if (DIEEntry *Entry = ModuleCU->getDIEEntry(CATy.getNode()))
+        ModuleCU->addGlobalType(CATy.getName(), Entry->getEntry());
+    }
+  }
+}
+
+/// constructScopeDIE - Construct a DIE for this scope.
+DIE *DwarfDebug::constructScopeDIE(DbgScope *Scope) {
+ if (!Scope)
+  return NULL;
+ DIScope DS(Scope->getScopeNode());
+ if (DS.isNull())
+   return NULL;
+
+ DIE *ScopeDIE = NULL;
+ if (Scope->getInlinedAt())
+   ScopeDIE = constructInlinedScopeDIE(Scope);
+ else if (DS.isSubprogram()) {
+   if (Scope->isAbstractScope())
+     ScopeDIE = ModuleCU->getDIE(DS.getNode());
+   else
+     ScopeDIE = updateSubprogramScopeDIE(DS.getNode());
+ }
+ else {
+   ScopeDIE = constructLexicalScopeDIE(Scope);
+   if (!ScopeDIE) return NULL;
+ }
+
+  // Add variables to scope.
+  SmallVector<DbgVariable *, 8> &Variables = Scope->getVariables();
+  for (unsigned i = 0, N = Variables.size(); i < N; ++i) {
+    DIE *VariableDIE = constructVariableDIE(Variables[i], Scope);
+    if (VariableDIE)
+      ScopeDIE->addChild(VariableDIE);
+  }
+
+  // Add nested scopes.
+  SmallVector<DbgScope *, 4> &Scopes = Scope->getScopes();
+  for (unsigned j = 0, M = Scopes.size(); j < M; ++j) {
+    // Define the Scope debug information entry.
+    DIE *NestedDIE = constructScopeDIE(Scopes[j]);
+    if (NestedDIE)
+      ScopeDIE->addChild(NestedDIE);
+  }
+
+  if (DS.isSubprogram()) 
+    addPubTypes(DISubprogram(DS.getNode()));
+ 
+ return ScopeDIE;
+}
+
+/// GetOrCreateSourceID - Look up the source id with the given directory and
+/// source file names. If none currently exists, create a new id and insert it
+/// in the SourceIds map. This can update DirectoryNames and SourceFileNames
+/// maps as well.
+unsigned DwarfDebug::GetOrCreateSourceID(StringRef DirName, StringRef FileName) {
+  unsigned DId;
+  StringMap<unsigned>::iterator DI = DirectoryIdMap.find(DirName);
+  if (DI != DirectoryIdMap.end()) {
+    DId = DI->getValue();
+  } else {
+    DId = DirectoryNames.size() + 1;
+    DirectoryIdMap[DirName] = DId;
+    DirectoryNames.push_back(DirName);
+  }
+
+  unsigned FId;
+  StringMap<unsigned>::iterator FI = SourceFileIdMap.find(FileName);
+  if (FI != SourceFileIdMap.end()) {
+    FId = FI->getValue();
+  } else {
+    FId = SourceFileNames.size() + 1;
+    SourceFileIdMap[FileName] = FId;
+    SourceFileNames.push_back(FileName);
+  }
+
+  DenseMap<std::pair<unsigned, unsigned>, unsigned>::iterator SI =
+    SourceIdMap.find(std::make_pair(DId, FId));
+  if (SI != SourceIdMap.end())
+    return SI->second;
+
+  unsigned SrcId = SourceIds.size() + 1;  // DW_AT_decl_file cannot be 0.
+  SourceIdMap[std::make_pair(DId, FId)] = SrcId;
+  SourceIds.push_back(std::make_pair(DId, FId));
+
+  return SrcId;
+}
+
+/// getOrCreateNameSpace - Create a DIE for DINameSpace.
+DIE *DwarfDebug::getOrCreateNameSpace(DINameSpace NS) {
+  DIE *NDie = ModuleCU->getDIE(NS.getNode());
+  if (NDie)
+    return NDie;
+  NDie = new DIE(dwarf::DW_TAG_namespace);
+  ModuleCU->insertDIE(NS.getNode(), NDie);
+  if (!NS.getName().empty())
+    addString(NDie, dwarf::DW_AT_name, dwarf::DW_FORM_string, NS.getName());
+  addSourceLine(NDie, &NS);
+  addToContextOwner(NDie, NS.getContext());
+  return NDie;
+}
+
+CompileUnit *DwarfDebug::constructCompileUnit(MDNode *N) {
+  DICompileUnit DIUnit(N);
+  StringRef FN = DIUnit.getFilename();
+  StringRef Dir = DIUnit.getDirectory();
+  unsigned ID = GetOrCreateSourceID(Dir, FN);
+
+  DIE *Die = new DIE(dwarf::DW_TAG_compile_unit);
+  addSectionOffset(Die, dwarf::DW_AT_stmt_list, dwarf::DW_FORM_data4,
+                   DWLabel("section_line", 0), DWLabel("section_line", 0),
+                   false);
+  addString(Die, dwarf::DW_AT_producer, dwarf::DW_FORM_string,
+            DIUnit.getProducer());
+  addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data1,
+          DIUnit.getLanguage());
+  addString(Die, dwarf::DW_AT_name, dwarf::DW_FORM_string, FN);
+
+  if (!Dir.empty())
+    addString(Die, dwarf::DW_AT_comp_dir, dwarf::DW_FORM_string, Dir);
+  if (DIUnit.isOptimized())
+    addUInt(Die, dwarf::DW_AT_APPLE_optimized, dwarf::DW_FORM_flag, 1);
+
+  StringRef Flags = DIUnit.getFlags();
+  if (!Flags.empty())
+    addString(Die, dwarf::DW_AT_APPLE_flags, dwarf::DW_FORM_string, Flags);
+
+  unsigned RVer = DIUnit.getRunTimeVersion();
+  if (RVer)
+    addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
+            dwarf::DW_FORM_data1, RVer);
+
+  CompileUnit *Unit = new CompileUnit(ID, Die);
+  if (!ModuleCU && DIUnit.isMain()) {
+    // Use first compile unit marked as isMain as the compile unit
+    // for this module.
+    ModuleCU = Unit;
+  }
+
+  CompileUnitMap[DIUnit.getNode()] = Unit;
+  CompileUnits.push_back(Unit);
+  return Unit;
+}
+
+void DwarfDebug::constructGlobalVariableDIE(MDNode *N) {
+  DIGlobalVariable DI_GV(N);
+
+  // If debug information is malformed then ignore it.
+  if (DI_GV.Verify() == false)
+    return;
+
+  // Check for pre-existence.
+  if (ModuleCU->getDIE(DI_GV.getNode()))
+    return;
+
+  DIE *VariableDie = createGlobalVariableDIE(DI_GV);
+  if (!VariableDie)
+    return;
+
+  // Add to map.
+  ModuleCU->insertDIE(N, VariableDie);
+
+  // Add to context owner.
+  DIDescriptor GVContext = DI_GV.getContext();
+  // Do not create specification DIE if context is either compile unit
+  // or a subprogram.
+  if (DI_GV.isDefinition() && !GVContext.isCompileUnit()
+      && !GVContext.isSubprogram()) {
+    // Create specification DIE.
+    DIE *VariableSpecDIE = new DIE(dwarf::DW_TAG_variable);
+    addDIEEntry(VariableSpecDIE, dwarf::DW_AT_specification,
+                dwarf::DW_FORM_ref4, VariableDie);
+    DIEBlock *Block = new DIEBlock();
+    addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
+    addObjectLabel(Block, 0, dwarf::DW_FORM_udata,
+                   Asm->GetGlobalValueSymbol(DI_GV.getGlobal()));
+    addBlock(VariableSpecDIE, dwarf::DW_AT_location, 0, Block);
+    addUInt(VariableDie, dwarf::DW_AT_declaration, dwarf::DW_FORM_flag, 1);
+    ModuleCU->addDie(VariableSpecDIE);
+  } else {
+    DIEBlock *Block = new DIEBlock();
+    addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
+    addObjectLabel(Block, 0, dwarf::DW_FORM_udata,
+                   Asm->GetGlobalValueSymbol(DI_GV.getGlobal()));
+    addBlock(VariableDie, dwarf::DW_AT_location, 0, Block);
+  }
+  addToContextOwner(VariableDie, GVContext);
+  
+  // Expose as global. FIXME - need to check external flag.
+  ModuleCU->addGlobal(DI_GV.getName(), VariableDie);
+
+  DIType GTy = DI_GV.getType();
+  if (GTy.isCompositeType() && !GTy.getName().empty()) {
+    DIEEntry *Entry = ModuleCU->getDIEEntry(GTy.getNode());
+    assert (Entry && "Missing global type!");
+    ModuleCU->addGlobalType(GTy.getName(), Entry->getEntry());
+  }
+  return;
+}
+
+void DwarfDebug::constructSubprogramDIE(MDNode *N) {
+  DISubprogram SP(N);
+
+  // Check for pre-existence.
+  if (ModuleCU->getDIE(N))
+    return;
+
+  if (!SP.isDefinition())
+    // This is a method declaration which will be handled while constructing
+    // class type.
+    return;
+
+  DIE *SubprogramDie = createSubprogramDIE(SP);
+
+  // Add to map.
+  ModuleCU->insertDIE(N, SubprogramDie);
+
+  // Add to context owner.
+  addToContextOwner(SubprogramDie, SP.getContext());
+
+  // Expose as global.
+  ModuleCU->addGlobal(SP.getName(), SubprogramDie);
+
+  return;
+}
+
+/// beginModule - Emit all Dwarf sections that should come prior to the
+/// content. Create global DIEs and emit initial debug info sections.
+/// This is inovked by the target AsmPrinter.
+void DwarfDebug::beginModule(Module *M, MachineModuleInfo *mmi) {
+  this->M = M;
+
+  if (TimePassesIsEnabled)
+    DebugTimer->startTimer();
+
+  if (!MAI->doesSupportDebugInformation())
+    return;
+
+  DebugInfoFinder DbgFinder;
+  DbgFinder.processModule(*M);
+
+  // Create all the compile unit DIEs.
+  for (DebugInfoFinder::iterator I = DbgFinder.compile_unit_begin(),
+         E = DbgFinder.compile_unit_end(); I != E; ++I)
+    constructCompileUnit(*I);
+
+  if (CompileUnits.empty()) {
+    if (TimePassesIsEnabled)
+      DebugTimer->stopTimer();
+
+    return;
+  }
+
+  // If main compile unit for this module is not seen than randomly
+  // select first compile unit.
+  if (!ModuleCU)
+    ModuleCU = CompileUnits[0];
+
+  // Create DIEs for each subprogram.
+  for (DebugInfoFinder::iterator I = DbgFinder.subprogram_begin(),
+         E = DbgFinder.subprogram_end(); I != E; ++I)
+    constructSubprogramDIE(*I);
+
+  // Create DIEs for each global variable.
+  for (DebugInfoFinder::iterator I = DbgFinder.global_variable_begin(),
+         E = DbgFinder.global_variable_end(); I != E; ++I)
+    constructGlobalVariableDIE(*I);
+
+  MMI = mmi;
+  shouldEmit = true;
+  MMI->setDebugInfoAvailability(true);
+
+  // Prime section data.
+  SectionMap.insert(Asm->getObjFileLowering().getTextSection());
+
+  // Print out .file directives to specify files for .loc directives. These are
+  // printed out early so that they precede any .loc directives.
+  if (MAI->hasDotLocAndDotFile()) {
+    for (unsigned i = 1, e = getNumSourceIds()+1; i != e; ++i) {
+      // Remember source id starts at 1.
+      std::pair<unsigned, unsigned> Id = getSourceDirectoryAndFileIds(i);
+      // FIXME: don't use sys::path for this!  This should not depend on the
+      // host.
+      sys::Path FullPath(getSourceDirectoryName(Id.first));
+      bool AppendOk =
+        FullPath.appendComponent(getSourceFileName(Id.second));
+      assert(AppendOk && "Could not append filename to directory!");
+      AppendOk = false;
+      Asm->OutStreamer.EmitDwarfFileDirective(i, FullPath.str());
+    }
+  }
+
+  // Emit initial sections
+  emitInitial();
+
+  if (TimePassesIsEnabled)
+    DebugTimer->stopTimer();
+}
+
+/// endModule - Emit all Dwarf sections that should come after the content.
+///
+void DwarfDebug::endModule() {
+  if (!ModuleCU)
+    return;
+
+  if (TimePassesIsEnabled)
+    DebugTimer->startTimer();
+
+  // Attach DW_AT_inline attribute with inlined subprogram DIEs.
+  for (SmallPtrSet<DIE *, 4>::iterator AI = InlinedSubprogramDIEs.begin(),
+         AE = InlinedSubprogramDIEs.end(); AI != AE; ++AI) {
+    DIE *ISP = *AI;
+    addUInt(ISP, dwarf::DW_AT_inline, 0, dwarf::DW_INL_inlined);
+  }
+
+  // Insert top level DIEs.
+  for (SmallVector<DIE *, 4>::iterator TI = TopLevelDIEsVector.begin(),
+         TE = TopLevelDIEsVector.end(); TI != TE; ++TI)
+    ModuleCU->getCUDie()->addChild(*TI);
+
+  for (DenseMap<DIE *, MDNode *>::iterator CI = ContainingTypeMap.begin(),
+         CE = ContainingTypeMap.end(); CI != CE; ++CI) {
+    DIE *SPDie = CI->first;
+    MDNode *N = dyn_cast_or_null<MDNode>(CI->second);
+    if (!N) continue;
+    DIE *NDie = ModuleCU->getDIE(N);
+    if (!NDie) continue;
+    addDIEEntry(SPDie, dwarf::DW_AT_containing_type, dwarf::DW_FORM_ref4, NDie);
+    // FIXME - This is not the correct approach.
+    // addDIEEntry(NDie, dwarf::DW_AT_containing_type, dwarf::DW_FORM_ref4, NDie);
+  }
+
+  // Standard sections final addresses.
+  Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering().getTextSection());
+  EmitLabel("text_end", 0);
+  Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering().getDataSection());
+  EmitLabel("data_end", 0);
+
+  // End text sections.
+  for (unsigned i = 1, N = SectionMap.size(); i <= N; ++i) {
+    Asm->OutStreamer.SwitchSection(SectionMap[i]);
+    EmitLabel("section_end", i);
+  }
+
+  // Emit common frame information.
+  emitCommonDebugFrame();
+
+  // Emit function debug frame information
+  for (std::vector<FunctionDebugFrameInfo>::iterator I = DebugFrames.begin(),
+         E = DebugFrames.end(); I != E; ++I)
+    emitFunctionDebugFrame(*I);
+
+  // Compute DIE offsets and sizes.
+  computeSizeAndOffsets();
+
+  // Emit all the DIEs into a debug info section
+  emitDebugInfo();
+
+  // Corresponding abbreviations into a abbrev section.
+  emitAbbreviations();
+
+  // Emit source line correspondence into a debug line section.
+  emitDebugLines();
+
+  // Emit info into a debug pubnames section.
+  emitDebugPubNames();
+
+  // Emit info into a debug pubtypes section.
+  emitDebugPubTypes();
+
+  // Emit info into a debug str section.
+  emitDebugStr();
+
+  // Emit info into a debug loc section.
+  emitDebugLoc();
+
+  // Emit info into a debug aranges section.
+  EmitDebugARanges();
+
+  // Emit info into a debug ranges section.
+  emitDebugRanges();
+
+  // Emit info into a debug macinfo section.
+  emitDebugMacInfo();
+
+  // Emit inline info.
+  emitDebugInlineInfo();
+
+  if (TimePassesIsEnabled)
+    DebugTimer->stopTimer();
+}
+
+/// findAbstractVariable - Find abstract variable, if any, associated with Var.
+DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &Var,
+                                              unsigned FrameIdx,
+                                              DILocation &ScopeLoc) {
+
+  DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var.getNode());
+  if (AbsDbgVariable)
+    return AbsDbgVariable;
+
+  DbgScope *Scope = AbstractScopes.lookup(ScopeLoc.getScope().getNode());
+  if (!Scope)
+    return NULL;
+
+  AbsDbgVariable = new DbgVariable(Var, FrameIdx);
+  Scope->addVariable(AbsDbgVariable);
+  AbstractVariables[Var.getNode()] = AbsDbgVariable;
+  return AbsDbgVariable;
+}
+
+/// collectVariableInfo - Populate DbgScope entries with variables' info.
+void DwarfDebug::collectVariableInfo() {
+  if (!MMI) return;
+
+  MachineModuleInfo::VariableDbgInfoMapTy &VMap = MMI->getVariableDbgInfo();
+  for (MachineModuleInfo::VariableDbgInfoMapTy::iterator VI = VMap.begin(),
+         VE = VMap.end(); VI != VE; ++VI) {
+    MDNode *Var = VI->first;
+    if (!Var) continue;
+    DIVariable DV (Var);
+    std::pair< unsigned, MDNode *> VP = VI->second;
+    DILocation ScopeLoc(VP.second);
+
+    DbgScope *Scope =
+      ConcreteScopes.lookup(ScopeLoc.getOrigLocation().getNode());
+    if (!Scope)
+      Scope = DbgScopeMap.lookup(ScopeLoc.getScope().getNode());
+    // If variable scope is not found then skip this variable.
+    if (!Scope)
+      continue;
+
+    DbgVariable *RegVar = new DbgVariable(DV, VP.first);
+    Scope->addVariable(RegVar);
+    if (DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VP.first,
+                                                           ScopeLoc))
+      RegVar->setAbstractVariable(AbsDbgVariable);
+  }
+}
+
+/// beginScope - Process beginning of a scope starting at Label.
+void DwarfDebug::beginScope(const MachineInstr *MI, unsigned Label) {
+  InsnToDbgScopeMapTy::iterator I = DbgScopeBeginMap.find(MI);
+  if (I == DbgScopeBeginMap.end())
+    return;
+  ScopeVector &SD = I->second;
+  for (ScopeVector::iterator SDI = SD.begin(), SDE = SD.end();
+       SDI != SDE; ++SDI)
+    (*SDI)->setStartLabelID(Label);
+}
+
+/// endScope - Process end of a scope.
+void DwarfDebug::endScope(const MachineInstr *MI) {
+  InsnToDbgScopeMapTy::iterator I = DbgScopeEndMap.find(MI);
+  if (I == DbgScopeEndMap.end())
+    return;
+
+  unsigned Label = MMI->NextLabelID();
+  Asm->printLabel(Label);
+  O << '\n';
+
+  SmallVector<DbgScope *, 2> &SD = I->second;
+  for (SmallVector<DbgScope *, 2>::iterator SDI = SD.begin(), SDE = SD.end();
+       SDI != SDE; ++SDI)
+    (*SDI)->setEndLabelID(Label);
+  return;
+}
+
+/// createDbgScope - Create DbgScope for the scope.
+void DwarfDebug::createDbgScope(MDNode *Scope, MDNode *InlinedAt) {
+
+  if (!InlinedAt) {
+    DbgScope *WScope = DbgScopeMap.lookup(Scope);
+    if (WScope)
+      return;
+    WScope = new DbgScope(NULL, DIDescriptor(Scope), NULL);
+    DbgScopeMap.insert(std::make_pair(Scope, WScope));
+    if (DIDescriptor(Scope).isLexicalBlock())
+      createDbgScope(DILexicalBlock(Scope).getContext().getNode(), NULL);
+    return;
+  }
+
+  DbgScope *WScope = DbgScopeMap.lookup(InlinedAt);
+  if (WScope)
+    return;
+
+  WScope = new DbgScope(NULL, DIDescriptor(Scope), InlinedAt);
+  DbgScopeMap.insert(std::make_pair(InlinedAt, WScope));
+  DILocation DL(InlinedAt);
+  createDbgScope(DL.getScope().getNode(), DL.getOrigLocation().getNode());
+}
+
+/// extractScopeInformation - Scan machine instructions in this function
+/// and collect DbgScopes. Return true, if atleast one scope was found.
+bool DwarfDebug::extractScopeInformation() {
+  // If scope information was extracted using .dbg intrinsics then there is not
+  // any need to extract these information by scanning each instruction.
+  if (!DbgScopeMap.empty())
+    return false;
+
+  DenseMap<const MachineInstr *, unsigned> MIIndexMap;
+  unsigned MIIndex = 0;
+  // Scan each instruction and create scopes. First build working set of scopes.
+  for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
+       I != E; ++I) {
+    for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
+         II != IE; ++II) {
+      const MachineInstr *MInsn = II;
+      MIIndexMap[MInsn] = MIIndex++;
+      DebugLoc DL = MInsn->getDebugLoc();
+      if (DL.isUnknown()) continue;
+      DILocation DLT = MF->getDILocation(DL);
+      DIScope DLTScope = DLT.getScope();
+      if (DLTScope.isNull()) continue;
+      // There is no need to create another DIE for compile unit. For all
+      // other scopes, create one DbgScope now. This will be translated
+      // into a scope DIE at the end.
+      if (DLTScope.isCompileUnit()) continue;
+      createDbgScope(DLTScope.getNode(), DLT.getOrigLocation().getNode());
+    }
+  }
+
+
+  // Build scope hierarchy using working set of scopes.
+  for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
+       I != E; ++I) {
+    for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
+         II != IE; ++II) {
+      const MachineInstr *MInsn = II;
+      DebugLoc DL = MInsn->getDebugLoc();
+      if (DL.isUnknown())  continue;
+      DILocation DLT = MF->getDILocation(DL);
+      DIScope DLTScope = DLT.getScope();
+      if (DLTScope.isNull())  continue;
+      // There is no need to create another DIE for compile unit. For all
+      // other scopes, create one DbgScope now. This will be translated
+      // into a scope DIE at the end.
+      if (DLTScope.isCompileUnit()) continue;
+      DbgScope *Scope = getUpdatedDbgScope(DLTScope.getNode(), MInsn, 
+                                           DLT.getOrigLocation().getNode());
+      Scope->setLastInsn(MInsn);
+    }
+  }
+
+  if (!CurrentFnDbgScope)
+    return false;
+
+  CurrentFnDbgScope->fixInstructionMarkers(MIIndexMap);
+
+  // Each scope has first instruction and last instruction to mark beginning
+  // and end of a scope respectively. Create an inverse map that list scopes
+  // starts (and ends) with an instruction. One instruction may start (or end)
+  // multiple scopes. Ignore scopes that are not reachable.
+  SmallVector<DbgScope *, 4> WorkList;
+  WorkList.push_back(CurrentFnDbgScope);
+  while (!WorkList.empty()) {
+    DbgScope *S = WorkList.back(); WorkList.pop_back();
+
+    SmallVector<DbgScope *, 4> &Children = S->getScopes();
+    if (!Children.empty()) 
+      for (SmallVector<DbgScope *, 4>::iterator SI = Children.begin(),
+             SE = Children.end(); SI != SE; ++SI)
+        WorkList.push_back(*SI);
+
+    if (S->isAbstractScope())
+      continue;
+    const MachineInstr *MI = S->getFirstInsn();
+    assert (MI && "DbgScope does not have first instruction!");
+
+    InsnToDbgScopeMapTy::iterator IDI = DbgScopeBeginMap.find(MI);
+    if (IDI != DbgScopeBeginMap.end())
+      IDI->second.push_back(S);
+    else
+      DbgScopeBeginMap[MI].push_back(S);
+
+    MI = S->getLastInsn();
+    assert (MI && "DbgScope does not have last instruction!");
+    IDI = DbgScopeEndMap.find(MI);
+    if (IDI != DbgScopeEndMap.end())
+      IDI->second.push_back(S);
+    else
+      DbgScopeEndMap[MI].push_back(S);
+  }
+
+  return !DbgScopeMap.empty();
+}
+
+/// beginFunction - Gather pre-function debug information.  Assumes being
+/// emitted immediately after the function entry point.
+void DwarfDebug::beginFunction(const MachineFunction *MF) {
+  this->MF = MF;
+
+  if (!ShouldEmitDwarfDebug()) return;
+
+  if (TimePassesIsEnabled)
+    DebugTimer->startTimer();
+
+  if (!extractScopeInformation())
+    return;
+
+  collectVariableInfo();
+
+  // Assumes in correct section after the entry point.
+  EmitLabel("func_begin", ++SubprogramCount);
+
+  // Emit label for the implicitly defined dbg.stoppoint at the start of the
+  // function.
+  DebugLoc FDL = MF->getDefaultDebugLoc();
+  if (!FDL.isUnknown()) {
+    DILocation DLT = MF->getDILocation(FDL);
+    unsigned LabelID = 0;
+    DISubprogram SP = getDISubprogram(DLT.getScope().getNode());
+    if (!SP.isNull())
+      LabelID = recordSourceLine(SP.getLineNumber(), 0, 
+                                 DLT.getScope().getNode());
+    else
+      LabelID = recordSourceLine(DLT.getLineNumber(), 
+                                 DLT.getColumnNumber(), 
+                                 DLT.getScope().getNode());
+    Asm->printLabel(LabelID);
+    O << '\n';
+  }
+  if (TimePassesIsEnabled)
+    DebugTimer->stopTimer();
+}
+
+/// endFunction - Gather and emit post-function debug information.
+///
+void DwarfDebug::endFunction(const MachineFunction *MF) {
+  if (!ShouldEmitDwarfDebug()) return;
+
+  if (TimePassesIsEnabled)
+    DebugTimer->startTimer();
+
+  if (DbgScopeMap.empty())
+    return;
+
+  if (CurrentFnDbgScope) {
+    // Define end label for subprogram.
+    EmitLabel("func_end", SubprogramCount);
+    
+    // Get function line info.
+    if (!Lines.empty()) {
+      // Get section line info.
+      unsigned ID = SectionMap.insert(Asm->getCurrentSection());
+      if (SectionSourceLines.size() < ID) SectionSourceLines.resize(ID);
+      std::vector<SrcLineInfo> &SectionLineInfos = SectionSourceLines[ID-1];
+      // Append the function info to section info.
+      SectionLineInfos.insert(SectionLineInfos.end(),
+                              Lines.begin(), Lines.end());
+    }
+    
+    // Construct abstract scopes.
+    for (SmallVector<DbgScope *, 4>::iterator AI = AbstractScopesList.begin(),
+           AE = AbstractScopesList.end(); AI != AE; ++AI)
+      constructScopeDIE(*AI);
+    
+    constructScopeDIE(CurrentFnDbgScope);
+    
+    DebugFrames.push_back(FunctionDebugFrameInfo(SubprogramCount,
+                                                 MMI->getFrameMoves()));
+  }
+
+  // Clear debug info
+  CurrentFnDbgScope = NULL;
+  DbgScopeMap.clear();
+  DbgScopeBeginMap.clear();
+  DbgScopeEndMap.clear();
+  ConcreteScopes.clear();
+  AbstractScopesList.clear();
+  Lines.clear();
+  
+  if (TimePassesIsEnabled)
+    DebugTimer->stopTimer();
+}
+
+/// recordSourceLine - Records location information and associates it with a
+/// label. Returns a unique label ID used to generate a label and provide
+/// correspondence to the source line list.
+unsigned DwarfDebug::recordSourceLine(unsigned Line, unsigned Col,
+                                      MDNode *S) {
+  if (!MMI)
+    return 0;
+
+  if (TimePassesIsEnabled)
+    DebugTimer->startTimer();
+
+  StringRef Dir;
+  StringRef Fn;
+
+  DIDescriptor Scope(S);
+  if (Scope.isCompileUnit()) {
+    DICompileUnit CU(S);
+    Dir = CU.getDirectory();
+    Fn = CU.getFilename();
+  } else if (Scope.isSubprogram()) {
+    DISubprogram SP(S);
+    Dir = SP.getDirectory();
+    Fn = SP.getFilename();
+  } else if (Scope.isLexicalBlock()) {
+    DILexicalBlock DB(S);
+    Dir = DB.getDirectory();
+    Fn = DB.getFilename();
+  } else
+    assert (0 && "Unexpected scope info");
+
+  unsigned Src = GetOrCreateSourceID(Dir, Fn);
+  unsigned ID = MMI->NextLabelID();
+  Lines.push_back(SrcLineInfo(Line, Col, Src, ID));
+
+  if (TimePassesIsEnabled)
+    DebugTimer->stopTimer();
+
+  return ID;
+}
+
+/// getOrCreateSourceID - Public version of GetOrCreateSourceID. This can be
+/// timed. Look up the source id with the given directory and source file
+/// names. If none currently exists, create a new id and insert it in the
+/// SourceIds map. This can update DirectoryNames and SourceFileNames maps as
+/// well.
+unsigned DwarfDebug::getOrCreateSourceID(const std::string &DirName,
+                                         const std::string &FileName) {
+  if (TimePassesIsEnabled)
+    DebugTimer->startTimer();
+
+  unsigned SrcId = GetOrCreateSourceID(DirName.c_str(), FileName.c_str());
+
+  if (TimePassesIsEnabled)
+    DebugTimer->stopTimer();
+
+  return SrcId;
+}
+
+//===----------------------------------------------------------------------===//
+// Emit Methods
+//===----------------------------------------------------------------------===//
+
+/// computeSizeAndOffset - Compute the size and offset of a DIE.
+///
+unsigned
+DwarfDebug::computeSizeAndOffset(DIE *Die, unsigned Offset, bool Last) {
+  // Get the children.
+  const std::vector<DIE *> &Children = Die->getChildren();
+
+  // If not last sibling and has children then add sibling offset attribute.
+  if (!Last && !Children.empty()) Die->addSiblingOffset();
+
+  // Record the abbreviation.
+  assignAbbrevNumber(Die->getAbbrev());
+
+  // Get the abbreviation for this DIE.
+  unsigned AbbrevNumber = Die->getAbbrevNumber();
+  const DIEAbbrev *Abbrev = Abbreviations[AbbrevNumber - 1];
+
+  // Set DIE offset
+  Die->setOffset(Offset);
+
+  // Start the size with the size of abbreviation code.
+  Offset += MCAsmInfo::getULEB128Size(AbbrevNumber);
+
+  const SmallVector<DIEValue*, 32> &Values = Die->getValues();
+  const SmallVector<DIEAbbrevData, 8> &AbbrevData = Abbrev->getData();
+
+  // Size the DIE attribute values.
+  for (unsigned i = 0, N = Values.size(); i < N; ++i)
+    // Size attribute value.
+    Offset += Values[i]->SizeOf(TD, AbbrevData[i].getForm());
+
+  // Size the DIE children if any.
+  if (!Children.empty()) {
+    assert(Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes &&
+           "Children flag not set");
+
+    for (unsigned j = 0, M = Children.size(); j < M; ++j)
+      Offset = computeSizeAndOffset(Children[j], Offset, (j + 1) == M);
+
+    // End of children marker.
+    Offset += sizeof(int8_t);
+  }
+
+  Die->setSize(Offset - Die->getOffset());
+  return Offset;
+}
+
+/// computeSizeAndOffsets - Compute the size and offset of all the DIEs.
+///
+void DwarfDebug::computeSizeAndOffsets() {
+  // Compute size of compile unit header.
+  static unsigned Offset =
+    sizeof(int32_t) + // Length of Compilation Unit Info
+    sizeof(int16_t) + // DWARF version number
+    sizeof(int32_t) + // Offset Into Abbrev. Section
+    sizeof(int8_t);   // Pointer Size (in bytes)
+
+  computeSizeAndOffset(ModuleCU->getCUDie(), Offset, true);
+  CompileUnitOffsets[ModuleCU] = 0;
+}
+
+/// emitInitial - Emit initial Dwarf declarations.  This is necessary for cc
+/// tools to recognize the object file contains Dwarf information.
+void DwarfDebug::emitInitial() {
+  // Check to see if we already emitted intial headers.
+  if (didInitial) return;
+  didInitial = true;
+
+  const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
+
+  // Dwarf sections base addresses.
+  if (MAI->doesDwarfRequireFrameSection()) {
+    Asm->OutStreamer.SwitchSection(TLOF.getDwarfFrameSection());
+    EmitLabel("section_debug_frame", 0);
+  }
+
+  Asm->OutStreamer.SwitchSection(TLOF.getDwarfInfoSection());
+  EmitLabel("section_info", 0);
+  Asm->OutStreamer.SwitchSection(TLOF.getDwarfAbbrevSection());
+  EmitLabel("section_abbrev", 0);
+  Asm->OutStreamer.SwitchSection(TLOF.getDwarfARangesSection());
+  EmitLabel("section_aranges", 0);
+
+  if (const MCSection *LineInfoDirective = TLOF.getDwarfMacroInfoSection()) {
+    Asm->OutStreamer.SwitchSection(LineInfoDirective);
+    EmitLabel("section_macinfo", 0);
+  }
+
+  Asm->OutStreamer.SwitchSection(TLOF.getDwarfLineSection());
+  EmitLabel("section_line", 0);
+  Asm->OutStreamer.SwitchSection(TLOF.getDwarfLocSection());
+  EmitLabel("section_loc", 0);
+  Asm->OutStreamer.SwitchSection(TLOF.getDwarfPubNamesSection());
+  EmitLabel("section_pubnames", 0);
+  Asm->OutStreamer.SwitchSection(TLOF.getDwarfPubTypesSection());
+  EmitLabel("section_pubtypes", 0);
+  Asm->OutStreamer.SwitchSection(TLOF.getDwarfStrSection());
+  EmitLabel("section_str", 0);
+  Asm->OutStreamer.SwitchSection(TLOF.getDwarfRangesSection());
+  EmitLabel("section_ranges", 0);
+
+  Asm->OutStreamer.SwitchSection(TLOF.getTextSection());
+  EmitLabel("text_begin", 0);
+  Asm->OutStreamer.SwitchSection(TLOF.getDataSection());
+  EmitLabel("data_begin", 0);
+}
+
+/// emitDIE - Recusively Emits a debug information entry.
+///
+void DwarfDebug::emitDIE(DIE *Die) {
+  // Get the abbreviation for this DIE.
+  unsigned AbbrevNumber = Die->getAbbrevNumber();
+  const DIEAbbrev *Abbrev = Abbreviations[AbbrevNumber - 1];
+
+  Asm->O << '\n';
+
+  // Emit the code (index) for the abbreviation.
+  if (Asm->VerboseAsm)
+    Asm->OutStreamer.AddComment("Abbrev [" + Twine(AbbrevNumber) + "] 0x" +
+                                Twine::utohexstr(Die->getOffset()) + ":0x" +
+                                Twine::utohexstr(Die->getSize()) + " " +
+                                dwarf::TagString(Abbrev->getTag()));
+  EmitULEB128(AbbrevNumber);
+
+  SmallVector<DIEValue*, 32> &Values = Die->getValues();
+  const SmallVector<DIEAbbrevData, 8> &AbbrevData = Abbrev->getData();
+
+  // Emit the DIE attribute values.
+  for (unsigned i = 0, N = Values.size(); i < N; ++i) {
+    unsigned Attr = AbbrevData[i].getAttribute();
+    unsigned Form = AbbrevData[i].getForm();
+    assert(Form && "Too many attributes for DIE (check abbreviation)");
+
+    if (Asm->VerboseAsm)
+      Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
+    
+    switch (Attr) {
+    case dwarf::DW_AT_sibling:
+      Asm->EmitInt32(Die->getSiblingOffset());
+      break;
+    case dwarf::DW_AT_abstract_origin: {
+      DIEEntry *E = cast<DIEEntry>(Values[i]);
+      DIE *Origin = E->getEntry();
+      unsigned Addr = Origin->getOffset();
+      Asm->EmitInt32(Addr);
+      break;
+    }
+    default:
+      // Emit an attribute using the defined form.
+      Values[i]->EmitValue(this, Form);
+      O << "\n"; // REMOVE This once all EmitValue impls emit their own newline.
+      break;
+    }
+  }
+
+  // Emit the DIE children if any.
+  if (Abbrev->getChildrenFlag() == dwarf::DW_CHILDREN_yes) {
+    const std::vector<DIE *> &Children = Die->getChildren();
+
+    for (unsigned j = 0, M = Children.size(); j < M; ++j)
+      emitDIE(Children[j]);
+
+    Asm->EmitInt8(0); EOL("End Of Children Mark");
+  }
+}
+
+/// emitDebugInfo - Emit the debug info section.
+///
+void DwarfDebug::emitDebugInfo() {
+  // Start debug info section.
+  Asm->OutStreamer.SwitchSection(
+                            Asm->getObjFileLowering().getDwarfInfoSection());
+  DIE *Die = ModuleCU->getCUDie();
+
+  // Emit the compile units header.
+  EmitLabel("info_begin", ModuleCU->getID());
+
+  // Emit size of content not including length itself
+  unsigned ContentSize = Die->getSize() +
+    sizeof(int16_t) + // DWARF version number
+    sizeof(int32_t) + // Offset Into Abbrev. Section
+    sizeof(int8_t) +  // Pointer Size (in bytes)
+    sizeof(int32_t);  // FIXME - extra pad for gdb bug.
+
+  Asm->EmitInt32(ContentSize);  EOL("Length of Compilation Unit Info");
+  Asm->EmitInt16(dwarf::DWARF_VERSION); EOL("DWARF version number");
+  EmitSectionOffset("abbrev_begin", "section_abbrev", 0, 0, true, false);
+  EOL("Offset Into Abbrev. Section");
+  Asm->EmitInt8(TD->getPointerSize()); EOL("Address Size (in bytes)");
+
+  emitDIE(Die);
+  // FIXME - extra padding for gdb bug.
+  Asm->EmitInt8(0); EOL("Extra Pad For GDB");
+  Asm->EmitInt8(0); EOL("Extra Pad For GDB");
+  Asm->EmitInt8(0); EOL("Extra Pad For GDB");
+  Asm->EmitInt8(0); EOL("Extra Pad For GDB");
+  EmitLabel("info_end", ModuleCU->getID());
+  Asm->O << '\n';
+}
+
+/// emitAbbreviations - Emit the abbreviation section.
+///
+void DwarfDebug::emitAbbreviations() const {
+  // Check to see if it is worth the effort.
+  if (!Abbreviations.empty()) {
+    // Start the debug abbrev section.
+    Asm->OutStreamer.SwitchSection(
+                            Asm->getObjFileLowering().getDwarfAbbrevSection());
+
+    EmitLabel("abbrev_begin", 0);
+
+    // For each abbrevation.
+    for (unsigned i = 0, N = Abbreviations.size(); i < N; ++i) {
+      // Get abbreviation data
+      const DIEAbbrev *Abbrev = Abbreviations[i];
+
+      // Emit the abbrevations code (base 1 index.)
+      EmitULEB128(Abbrev->getNumber(), "Abbreviation Code");
+
+      // Emit the abbreviations data.
+      Abbrev->Emit(this);
+      Asm->O << '\n';
+    }
+
+    // Mark end of abbreviations.
+    EmitULEB128(0, "EOM(3)");
+
+    EmitLabel("abbrev_end", 0);
+    Asm->O << '\n';
+  }
+}
+
+/// emitEndOfLineMatrix - Emit the last address of the section and the end of
+/// the line matrix.
+///
+void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
+  // Define last address of section.
+  Asm->EmitInt8(0); EOL("Extended Op");
+  Asm->EmitInt8(TD->getPointerSize() + 1); EOL("Op size");
+  Asm->EmitInt8(dwarf::DW_LNE_set_address); EOL("DW_LNE_set_address");
+  EmitReference("section_end", SectionEnd); EOL("Section end label");
+
+  // Mark end of matrix.
+  Asm->EmitInt8(0); EOL("DW_LNE_end_sequence");
+  Asm->EmitInt8(1);
+  Asm->EmitInt8(1);
+}
+
+/// emitDebugLines - Emit source line information.
+///
+void DwarfDebug::emitDebugLines() {
+  // If the target is using .loc/.file, the assembler will be emitting the
+  // .debug_line table automatically.
+  if (MAI->hasDotLocAndDotFile())
+    return;
+
+  // Minimum line delta, thus ranging from -10..(255-10).
+  const int MinLineDelta = -(dwarf::DW_LNS_fixed_advance_pc + 1);
+  // Maximum line delta, thus ranging from -10..(255-10).
+  const int MaxLineDelta = 255 + MinLineDelta;
+
+  // Start the dwarf line section.
+  Asm->OutStreamer.SwitchSection(
+                            Asm->getObjFileLowering().getDwarfLineSection());
+
+  // Construct the section header.
+  EmitDifference("line_end", 0, "line_begin", 0, true);
+  EOL("Length of Source Line Info");
+  EmitLabel("line_begin", 0);
+
+  Asm->EmitInt16(dwarf::DWARF_VERSION); EOL("DWARF version number");
+
+  EmitDifference("line_prolog_end", 0, "line_prolog_begin", 0, true);
+  EOL("Prolog Length");
+  EmitLabel("line_prolog_begin", 0);
+
+  Asm->EmitInt8(1); EOL("Minimum Instruction Length");
+  Asm->EmitInt8(1); EOL("Default is_stmt_start flag");
+  Asm->EmitInt8(MinLineDelta); EOL("Line Base Value (Special Opcodes)");
+  Asm->EmitInt8(MaxLineDelta); EOL("Line Range Value (Special Opcodes)");
+  Asm->EmitInt8(-MinLineDelta); EOL("Special Opcode Base");
+
+  // Line number standard opcode encodings argument count
+  Asm->EmitInt8(0); EOL("DW_LNS_copy arg count");
+  Asm->EmitInt8(1); EOL("DW_LNS_advance_pc arg count");
+  Asm->EmitInt8(1); EOL("DW_LNS_advance_line arg count");
+  Asm->EmitInt8(1); EOL("DW_LNS_set_file arg count");
+  Asm->EmitInt8(1); EOL("DW_LNS_set_column arg count");
+  Asm->EmitInt8(0); EOL("DW_LNS_negate_stmt arg count");
+  Asm->EmitInt8(0); EOL("DW_LNS_set_basic_block arg count");
+  Asm->EmitInt8(0); EOL("DW_LNS_const_add_pc arg count");
+  Asm->EmitInt8(1); EOL("DW_LNS_fixed_advance_pc arg count");
+
+  // Emit directories.
+  for (unsigned DI = 1, DE = getNumSourceDirectories()+1; DI != DE; ++DI) {
+    const std::string &Dir = getSourceDirectoryName(DI);
+    if (Asm->VerboseAsm) Asm->OutStreamer.AddComment("Directory");
+    Asm->OutStreamer.EmitBytes(StringRef(Dir.c_str(), Dir.size()+1), 0);
+  }
+
+  Asm->EmitInt8(0); EOL("End of directories");
+
+  // Emit files.
+  for (unsigned SI = 1, SE = getNumSourceIds()+1; SI != SE; ++SI) {
+    // Remember source id starts at 1.
+    std::pair<unsigned, unsigned> Id = getSourceDirectoryAndFileIds(SI);
+    const std::string &FN = getSourceFileName(Id.second);
+    if (Asm->VerboseAsm) Asm->OutStreamer.AddComment("Source");
+    Asm->OutStreamer.EmitBytes(StringRef(FN.c_str(), FN.size()+1), 0);
+    
+    EmitULEB128(Id.first, "Directory #");
+    EmitULEB128(0, "Mod date");
+    EmitULEB128(0, "File size");
+  }
+
+  Asm->EmitInt8(0); EOL("End of files");
+
+  EmitLabel("line_prolog_end", 0);
+
+  // A sequence for each text section.
+  unsigned SecSrcLinesSize = SectionSourceLines.size();
+
+  for (unsigned j = 0; j < SecSrcLinesSize; ++j) {
+    // Isolate current sections line info.
+    const std::vector<SrcLineInfo> &LineInfos = SectionSourceLines[j];
+
+    /*if (Asm->isVerbose()) {
+      const MCSection *S = SectionMap[j + 1];
+      O << '\t' << MAI->getCommentString() << " Section"
+        << S->getName() << '\n';
+    }*/
+    Asm->O << '\n';
+
+    // Dwarf assumes we start with first line of first source file.
+    unsigned Source = 1;
+    unsigned Line = 1;
+
+    // Construct rows of the address, source, line, column matrix.
+    for (unsigned i = 0, N = LineInfos.size(); i < N; ++i) {
+      const SrcLineInfo &LineInfo = LineInfos[i];
+      unsigned LabelID = MMI->MappedLabel(LineInfo.getLabelID());
+      if (!LabelID) continue;
+
+      if (LineInfo.getLine() == 0) continue;
+
+      if (!Asm->isVerbose())
+        Asm->O << '\n';
+      else {
+        std::pair<unsigned, unsigned> SourceID =
+          getSourceDirectoryAndFileIds(LineInfo.getSourceID());
+        O << '\t' << MAI->getCommentString() << ' '
+          << getSourceDirectoryName(SourceID.first) << '/'
+          << getSourceFileName(SourceID.second)
+          << ':' << utostr_32(LineInfo.getLine()) << '\n';
+      }
+
+      // Define the line address.
+      Asm->EmitInt8(0); EOL("Extended Op");
+      Asm->EmitInt8(TD->getPointerSize() + 1); EOL("Op size");
+      Asm->EmitInt8(dwarf::DW_LNE_set_address); EOL("DW_LNE_set_address");
+      EmitReference("label",  LabelID); EOL("Location label");
+
+      // If change of source, then switch to the new source.
+      if (Source != LineInfo.getSourceID()) {
+        Source = LineInfo.getSourceID();
+        Asm->EmitInt8(dwarf::DW_LNS_set_file); EOL("DW_LNS_set_file");
+        EmitULEB128(Source, "New Source");
+      }
+
+      // If change of line.
+      if (Line != LineInfo.getLine()) {
+        // Determine offset.
+        int Offset = LineInfo.getLine() - Line;
+        int Delta = Offset - MinLineDelta;
+
+        // Update line.
+        Line = LineInfo.getLine();
+
+        // If delta is small enough and in range...
+        if (Delta >= 0 && Delta < (MaxLineDelta - 1)) {
+          // ... then use fast opcode.
+          Asm->EmitInt8(Delta - MinLineDelta); EOL("Line Delta");
+        } else {
+          // ... otherwise use long hand.
+          Asm->EmitInt8(dwarf::DW_LNS_advance_line);
+          EOL("DW_LNS_advance_line");
+          EmitSLEB128(Offset, "Line Offset");
+          Asm->EmitInt8(dwarf::DW_LNS_copy); EOL("DW_LNS_copy");
+        }
+      } else {
+        // Copy the previous row (different address or source)
+        Asm->EmitInt8(dwarf::DW_LNS_copy); EOL("DW_LNS_copy");
+      }
+    }
+
+    emitEndOfLineMatrix(j + 1);
+  }
+
+  if (SecSrcLinesSize == 0)
+    // Because we're emitting a debug_line section, we still need a line
+    // table. The linker and friends expect it to exist. If there's nothing to
+    // put into it, emit an empty table.
+    emitEndOfLineMatrix(1);
+
+  EmitLabel("line_end", 0);
+  Asm->O << '\n';
+}
+
+/// emitCommonDebugFrame - Emit common frame info into a debug frame section.
+///
+void DwarfDebug::emitCommonDebugFrame() {
+  if (!MAI->doesDwarfRequireFrameSection())
+    return;
+
+  int stackGrowth =
+    Asm->TM.getFrameInfo()->getStackGrowthDirection() ==
+      TargetFrameInfo::StackGrowsUp ?
+    TD->getPointerSize() : -TD->getPointerSize();
+
+  // Start the dwarf frame section.
+  Asm->OutStreamer.SwitchSection(
+                              Asm->getObjFileLowering().getDwarfFrameSection());
+
+  EmitLabel("debug_frame_common", 0);
+  EmitDifference("debug_frame_common_end", 0,
+                 "debug_frame_common_begin", 0, true);
+  EOL("Length of Common Information Entry");
+
+  EmitLabel("debug_frame_common_begin", 0);
+  Asm->EmitInt32((int)dwarf::DW_CIE_ID);
+  EOL("CIE Identifier Tag");
+  Asm->EmitInt8(dwarf::DW_CIE_VERSION);
+  EOL("CIE Version");
+  Asm->OutStreamer.EmitIntValue(0, 1, /*addrspace*/0); // nul terminator.
+  EOL("CIE Augmentation");
+  EmitULEB128(1, "CIE Code Alignment Factor");
+  EmitSLEB128(stackGrowth, "CIE Data Alignment Factor");
+  Asm->EmitInt8(RI->getDwarfRegNum(RI->getRARegister(), false));
+  EOL("CIE RA Column");
+
+  std::vector<MachineMove> Moves;
+  RI->getInitialFrameState(Moves);
+
+  EmitFrameMoves(NULL, 0, Moves, false);
+
+  Asm->EmitAlignment(2, 0, 0, false);
+  EmitLabel("debug_frame_common_end", 0);
+  Asm->O << '\n';
+}
+
+/// emitFunctionDebugFrame - Emit per function frame info into a debug frame
+/// section.
+void
+DwarfDebug::emitFunctionDebugFrame(const FunctionDebugFrameInfo&DebugFrameInfo){
+  if (!MAI->doesDwarfRequireFrameSection())
+    return;
+
+  // Start the dwarf frame section.
+  Asm->OutStreamer.SwitchSection(
+                              Asm->getObjFileLowering().getDwarfFrameSection());
+
+  EmitDifference("debug_frame_end", DebugFrameInfo.Number,
+                 "debug_frame_begin", DebugFrameInfo.Number, true);
+  EOL("Length of Frame Information Entry");
+
+  EmitLabel("debug_frame_begin", DebugFrameInfo.Number);
+
+  EmitSectionOffset("debug_frame_common", "section_debug_frame",
+                    0, 0, true, false);
+  EOL("FDE CIE offset");
+
+  EmitReference("func_begin", DebugFrameInfo.Number);
+  EOL("FDE initial location");
+  EmitDifference("func_end", DebugFrameInfo.Number,
+                 "func_begin", DebugFrameInfo.Number);
+  EOL("FDE address range");
+
+  EmitFrameMoves("func_begin", DebugFrameInfo.Number, DebugFrameInfo.Moves,
+                 false);
+
+  Asm->EmitAlignment(2, 0, 0, false);
+  EmitLabel("debug_frame_end", DebugFrameInfo.Number);
+  Asm->O << '\n';
+}
+
+/// emitDebugPubNames - Emit visible names into a debug pubnames section.
+///
+void DwarfDebug::emitDebugPubNames() {
+  // Start the dwarf pubnames section.
+  Asm->OutStreamer.SwitchSection(
+                          Asm->getObjFileLowering().getDwarfPubNamesSection());
+
+  EmitDifference("pubnames_end", ModuleCU->getID(),
+                 "pubnames_begin", ModuleCU->getID(), true);
+  EOL("Length of Public Names Info");
+
+  EmitLabel("pubnames_begin", ModuleCU->getID());
+
+  Asm->EmitInt16(dwarf::DWARF_VERSION); EOL("DWARF Version");
+
+  EmitSectionOffset("info_begin", "section_info",
+                    ModuleCU->getID(), 0, true, false);
+  EOL("Offset of Compilation Unit Info");
+
+  EmitDifference("info_end", ModuleCU->getID(), "info_begin", ModuleCU->getID(),
+                 true);
+  EOL("Compilation Unit Length");
+
+  const StringMap<DIE*> &Globals = ModuleCU->getGlobals();
+  for (StringMap<DIE*>::const_iterator
+         GI = Globals.begin(), GE = Globals.end(); GI != GE; ++GI) {
+    const char *Name = GI->getKeyData();
+    DIE * Entity = GI->second;
+
+    Asm->EmitInt32(Entity->getOffset()); EOL("DIE offset");
+    
+    if (Asm->VerboseAsm)
+      Asm->OutStreamer.AddComment("External Name");
+    Asm->OutStreamer.EmitBytes(StringRef(Name, strlen(Name)+1), 0);
+  }
+
+  Asm->EmitInt32(0); EOL("End Mark");
+  EmitLabel("pubnames_end", ModuleCU->getID());
+  Asm->O << '\n';
+}
+
+void DwarfDebug::emitDebugPubTypes() {
+  // Start the dwarf pubnames section.
+  Asm->OutStreamer.SwitchSection(
+                          Asm->getObjFileLowering().getDwarfPubTypesSection());
+  EmitDifference("pubtypes_end", ModuleCU->getID(),
+                 "pubtypes_begin", ModuleCU->getID(), true);
+  EOL("Length of Public Types Info");
+
+  EmitLabel("pubtypes_begin", ModuleCU->getID());
+
+  if (Asm->VerboseAsm) Asm->OutStreamer.AddComment("DWARF Version");
+  Asm->EmitInt16(dwarf::DWARF_VERSION);
+
+  EmitSectionOffset("info_begin", "section_info",
+                    ModuleCU->getID(), 0, true, false);
+  EOL("Offset of Compilation ModuleCU Info");
+
+  EmitDifference("info_end", ModuleCU->getID(), "info_begin", ModuleCU->getID(),
+                 true);
+  EOL("Compilation ModuleCU Length");
+
+  const StringMap<DIE*> &Globals = ModuleCU->getGlobalTypes();
+  for (StringMap<DIE*>::const_iterator
+         GI = Globals.begin(), GE = Globals.end(); GI != GE; ++GI) {
+    const char *Name = GI->getKeyData();
+    DIE * Entity = GI->second;
+
+    if (Asm->VerboseAsm) Asm->OutStreamer.AddComment("DIE offset");
+    Asm->EmitInt32(Entity->getOffset());
+    
+    if (Asm->VerboseAsm) Asm->OutStreamer.AddComment("External Name");
+    Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength()+1), 0);
+  }
+
+  Asm->EmitInt32(0); EOL("End Mark");
+  EmitLabel("pubtypes_end", ModuleCU->getID());
+  Asm->O << '\n';
+}
+
+/// emitDebugStr - Emit visible names into a debug str section.
+///
+void DwarfDebug::emitDebugStr() {
+  // Check to see if it is worth the effort.
+  if (!StringPool.empty()) {
+    // Start the dwarf str section.
+    Asm->OutStreamer.SwitchSection(
+                                Asm->getObjFileLowering().getDwarfStrSection());
+
+    // For each of strings in the string pool.
+    for (unsigned StringID = 1, N = StringPool.size();
+         StringID <= N; ++StringID) {
+      // Emit a label for reference from debug information entries.
+      EmitLabel("string", StringID);
+
+      // Emit the string itself.
+      const std::string &String = StringPool[StringID];
+      Asm->OutStreamer.EmitBytes(StringRef(String.c_str(), String.size()+1), 0);
+    }
+
+    Asm->O << '\n';
+  }
+}
+
+/// emitDebugLoc - Emit visible names into a debug loc section.
+///
+void DwarfDebug::emitDebugLoc() {
+  // Start the dwarf loc section.
+  Asm->OutStreamer.SwitchSection(
+                              Asm->getObjFileLowering().getDwarfLocSection());
+}
+
+/// EmitDebugARanges - Emit visible names into a debug aranges section.
+///
+void DwarfDebug::EmitDebugARanges() {
+  // Start the dwarf aranges section.
+  Asm->OutStreamer.SwitchSection(
+                          Asm->getObjFileLowering().getDwarfARangesSection());
+
+  // FIXME - Mock up
+#if 0
+  CompileUnit *Unit = GetBaseCompileUnit();
+
+  // Don't include size of length
+  Asm->EmitInt32(0x1c); EOL("Length of Address Ranges Info");
+
+  Asm->EmitInt16(dwarf::DWARF_VERSION); EOL("Dwarf Version");
+
+  EmitReference("info_begin", Unit->getID());
+  EOL("Offset of Compilation Unit Info");
+
+  Asm->EmitInt8(TD->getPointerSize()); EOL("Size of Address");
+
+  Asm->EmitInt8(0); EOL("Size of Segment Descriptor");
+
+  Asm->EmitInt16(0);  EOL("Pad (1)");
+  Asm->EmitInt16(0);  EOL("Pad (2)");
+
+  // Range 1
+  EmitReference("text_begin", 0); EOL("Address");
+  EmitDifference("text_end", 0, "text_begin", 0, true); EOL("Length");
+
+  Asm->EmitInt32(0); EOL("EOM (1)");
+  Asm->EmitInt32(0); EOL("EOM (2)");
+#endif
+}
+
+/// emitDebugRanges - Emit visible names into a debug ranges section.
+///
+void DwarfDebug::emitDebugRanges() {
+  // Start the dwarf ranges section.
+  Asm->OutStreamer.SwitchSection(
+                            Asm->getObjFileLowering().getDwarfRangesSection());
+}
+
+/// emitDebugMacInfo - Emit visible names into a debug macinfo section.
+///
+void DwarfDebug::emitDebugMacInfo() {
+  if (const MCSection *LineInfo =
+      Asm->getObjFileLowering().getDwarfMacroInfoSection()) {
+    // Start the dwarf macinfo section.
+    Asm->OutStreamer.SwitchSection(LineInfo);
+  }
+}
+
+/// emitDebugInlineInfo - Emit inline info using following format.
+/// Section Header:
+/// 1. length of section
+/// 2. Dwarf version number
+/// 3. address size.
+///
+/// Entries (one "entry" for each function that was inlined):
+///
+/// 1. offset into __debug_str section for MIPS linkage name, if exists;
+///   otherwise offset into __debug_str for regular function name.
+/// 2. offset into __debug_str section for regular function name.
+/// 3. an unsigned LEB128 number indicating the number of distinct inlining
+/// instances for the function.
+///
+/// The rest of the entry consists of a {die_offset, low_pc} pair for each
+/// inlined instance; the die_offset points to the inlined_subroutine die in the
+/// __debug_info section, and the low_pc is the starting address for the
+/// inlining instance.
+void DwarfDebug::emitDebugInlineInfo() {
+  if (!MAI->doesDwarfUsesInlineInfoSection())
+    return;
+
+  if (!ModuleCU)
+    return;
+
+  Asm->OutStreamer.SwitchSection(
+                        Asm->getObjFileLowering().getDwarfDebugInlineSection());
+
+  EmitDifference("debug_inlined_end", 1,
+                 "debug_inlined_begin", 1, true);
+  EOL("Length of Debug Inlined Information Entry");
+
+  EmitLabel("debug_inlined_begin", 1);
+
+  Asm->EmitInt16(dwarf::DWARF_VERSION); EOL("Dwarf Version");
+  Asm->EmitInt8(TD->getPointerSize()); EOL("Address Size (in bytes)");
+
+  for (SmallVector<MDNode *, 4>::iterator I = InlinedSPNodes.begin(),
+         E = InlinedSPNodes.end(); I != E; ++I) {
+
+    MDNode *Node = *I;
+    DenseMap<MDNode *, SmallVector<InlineInfoLabels, 4> >::iterator II
+      = InlineInfo.find(Node);
+    SmallVector<InlineInfoLabels, 4> &Labels = II->second;
+    DISubprogram SP(Node);
+    StringRef LName = SP.getLinkageName();
+    StringRef Name = SP.getName();
+
+    if (LName.empty()) {
+      Asm->OutStreamer.EmitBytes(Name, 0);
+      Asm->OutStreamer.EmitIntValue(0, 1, 0); // nul terminator.
+    } else 
+      EmitSectionOffset("string", "section_str",
+                      StringPool.idFor(getRealLinkageName(LName)), false, true);
+
+    EOL("MIPS linkage name");
+    EmitSectionOffset("string", "section_str",
+                      StringPool.idFor(Name), false, true);
+    EOL("Function name");
+    EmitULEB128(Labels.size(), "Inline count");
+
+    for (SmallVector<InlineInfoLabels, 4>::iterator LI = Labels.begin(),
+           LE = Labels.end(); LI != LE; ++LI) {
+      DIE *SP = LI->second;
+      Asm->EmitInt32(SP->getOffset()); EOL("DIE offset");
+
+      if (TD->getPointerSize() == sizeof(int32_t))
+        O << MAI->getData32bitsDirective();
+      else
+        O << MAI->getData64bitsDirective();
+
+      PrintLabelName("label", LI->first); EOL("low_pc");
+    }
+  }
+
+  EmitLabel("debug_inlined_end", 1);
+  Asm->O << '\n';
+}
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.h b/lib/CodeGen/AsmPrinter/DwarfDebug.h
new file mode 100644
index 0000000000..55baa92100
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -0,0 +1,566 @@
+//===-- llvm/CodeGen/DwarfDebug.h - Dwarf Debug Framework ------*- C++ -*--===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for writing dwarf debug info into asm files.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef CODEGEN_ASMPRINTER_DWARFDEBUG_H__
+#define CODEGEN_ASMPRINTER_DWARFDEBUG_H__
+
+#include "DIE.h"
+#include "DwarfPrinter.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/CodeGen/MachineLocation.h"
+#include "llvm/Analysis/DebugInfo.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/FoldingSet.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/UniqueVector.h"
+#include <string>
+
+namespace llvm {
+
+class CompileUnit;
+class DbgConcreteScope;
+class DbgScope;
+class DbgVariable;
+class MachineFrameInfo;
+class MachineModuleInfo;
+class MCAsmInfo;
+class Timer;
+
+//===----------------------------------------------------------------------===//
+/// SrcLineInfo - This class is used to record source line correspondence.
+///
+class SrcLineInfo {
+  unsigned Line;                     // Source line number.
+  unsigned Column;                   // Source column.
+  unsigned SourceID;                 // Source ID number.
+  unsigned LabelID;                  // Label in code ID number.
+public:
+  SrcLineInfo(unsigned L, unsigned C, unsigned S, unsigned I)
+    : Line(L), Column(C), SourceID(S), LabelID(I) {}
+
+  // Accessors
+  unsigned getLine() const { return Line; }
+  unsigned getColumn() const { return Column; }
+  unsigned getSourceID() const { return SourceID; }
+  unsigned getLabelID() const { return LabelID; }
+};
+
+class DwarfDebug : public DwarfPrinter {
+  //===--------------------------------------------------------------------===//
+  // Attributes used to construct specific Dwarf sections.
+  //
+
+  /// CompileUnitMap - A map of global variables representing compile units to
+  /// compile units.
+  DenseMap<Value *, CompileUnit *> CompileUnitMap;
+
+  /// CompileUnits - All the compile units in this module.
+  ///
+  SmallVector<CompileUnit *, 8> CompileUnits;
+
+  /// ModuleCU - All DIEs are inserted in ModuleCU.
+  CompileUnit *ModuleCU;
+
+  /// AbbreviationsSet - Used to uniquely define abbreviations.
+  ///
+  FoldingSet<DIEAbbrev> AbbreviationsSet;
+
+  /// Abbreviations - A list of all the unique abbreviations in use.
+  ///
+  std::vector<DIEAbbrev *> Abbreviations;
+
+  /// DirectoryIdMap - Directory name to directory id map.
+  ///
+  StringMap<unsigned> DirectoryIdMap;
+
+  /// DirectoryNames - A list of directory names.
+  SmallVector<std::string, 8> DirectoryNames;
+
+  /// SourceFileIdMap - Source file name to source file id map.
+  ///
+  StringMap<unsigned> SourceFileIdMap;
+
+  /// SourceFileNames - A list of source file names.
+  SmallVector<std::string, 8> SourceFileNames;
+
+  /// SourceIdMap - Source id map, i.e. pair of directory id and source file
+  /// id mapped to a unique id.
+  DenseMap<std::pair<unsigned, unsigned>, unsigned> SourceIdMap;
+
+  /// SourceIds - Reverse map from source id to directory id + file id pair.
+  ///
+  SmallVector<std::pair<unsigned, unsigned>, 8> SourceIds;
+
+  /// Lines - List of source line correspondence.
+  std::vector<SrcLineInfo> Lines;
+
+  /// DIEValues - A list of all the unique values in use.
+  ///
+  std::vector<DIEValue *> DIEValues;
+
+  /// StringPool - A UniqueVector of strings used by indirect references.
+  ///
+  UniqueVector<std::string> StringPool;
+
+  /// SectionMap - Provides a unique id per text section.
+  ///
+  UniqueVector<const MCSection*> SectionMap;
+
+  /// SectionSourceLines - Tracks line numbers per text section.
+  ///
+  std::vector<std::vector<SrcLineInfo> > SectionSourceLines;
+
+  /// didInitial - Flag to indicate if initial emission has been done.
+  ///
+  bool didInitial;
+
+  /// shouldEmit - Flag to indicate if debug information should be emitted.
+  ///
+  bool shouldEmit;
+
+  // CurrentFnDbgScope - Top level scope for the current function.
+  //
+  DbgScope *CurrentFnDbgScope;
+  
+  /// DbgScopeMap - Tracks the scopes in the current function.
+  ///
+  DenseMap<MDNode *, DbgScope *> DbgScopeMap;
+
+  /// ConcreteScopes - Tracks the concrete scopees in the current function.
+  /// These scopes are also included in DbgScopeMap.
+  DenseMap<MDNode *, DbgScope *> ConcreteScopes;
+
+  /// AbstractScopes - Tracks the abstract scopes a module. These scopes are
+  /// not included DbgScopeMap.
+  DenseMap<MDNode *, DbgScope *> AbstractScopes;
+  SmallVector<DbgScope *, 4>AbstractScopesList;
+
+  /// AbstractVariables - Collection on abstract variables.
+  DenseMap<MDNode *, DbgVariable *> AbstractVariables;
+
+  /// InliendSubprogramDIEs - Collection of subprgram DIEs that are marked
+  /// (at the end of the module) as DW_AT_inline.
+  SmallPtrSet<DIE *, 4> InlinedSubprogramDIEs;
+
+  DenseMap<DIE *, MDNode *> ContainingTypeMap;
+
+  /// AbstractSubprogramDIEs - Collection of abstruct subprogram DIEs.
+  SmallPtrSet<DIE *, 4> AbstractSubprogramDIEs;
+
+  /// TopLevelDIEs - Collection of top level DIEs. 
+  SmallPtrSet<DIE *, 4> TopLevelDIEs;
+  SmallVector<DIE *, 4> TopLevelDIEsVector;
+
+  typedef SmallVector<DbgScope *, 2> ScopeVector;
+  typedef DenseMap<const MachineInstr *, ScopeVector>
+    InsnToDbgScopeMapTy;
+
+  /// DbgScopeBeginMap - Maps instruction with a list of DbgScopes it starts.
+  InsnToDbgScopeMapTy DbgScopeBeginMap;
+
+  /// DbgScopeEndMap - Maps instruction with a list DbgScopes it ends.
+  InsnToDbgScopeMapTy DbgScopeEndMap;
+
+  /// InlineInfo - Keep track of inlined functions and their location.  This
+  /// information is used to populate debug_inlined section.
+  typedef std::pair<unsigned, DIE *> InlineInfoLabels;
+  DenseMap<MDNode *, SmallVector<InlineInfoLabels, 4> > InlineInfo;
+  SmallVector<MDNode *, 4> InlinedSPNodes;
+
+  /// CompileUnitOffsets - A vector of the offsets of the compile units. This is
+  /// used when calculating the "origin" of a concrete instance of an inlined
+  /// function.
+  DenseMap<CompileUnit *, unsigned> CompileUnitOffsets;
+
+  /// DebugTimer - Timer for the Dwarf debug writer.
+  Timer *DebugTimer;
+  
+  struct FunctionDebugFrameInfo {
+    unsigned Number;
+    std::vector<MachineMove> Moves;
+
+    FunctionDebugFrameInfo(unsigned Num, const std::vector<MachineMove> &M)
+      : Number(Num), Moves(M) {}
+  };
+
+  std::vector<FunctionDebugFrameInfo> DebugFrames;
+
+  /// getSourceDirectoryAndFileIds - Return the directory and file ids that
+  /// maps to the source id. Source id starts at 1.
+  std::pair<unsigned, unsigned>
+  getSourceDirectoryAndFileIds(unsigned SId) const {
+    return SourceIds[SId-1];
+  }
+
+  /// getNumSourceDirectories - Return the number of source directories in the
+  /// debug info.
+  unsigned getNumSourceDirectories() const {
+    return DirectoryNames.size();
+  }
+
+  /// getSourceDirectoryName - Return the name of the directory corresponding
+  /// to the id.
+  const std::string &getSourceDirectoryName(unsigned Id) const {
+    return DirectoryNames[Id - 1];
+  }
+
+  /// getSourceFileName - Return the name of the source file corresponding
+  /// to the id.
+  const std::string &getSourceFileName(unsigned Id) const {
+    return SourceFileNames[Id - 1];
+  }
+
+  /// getNumSourceIds - Return the number of unique source ids.
+  unsigned getNumSourceIds() const {
+    return SourceIds.size();
+  }
+
+  /// assignAbbrevNumber - Define a unique number for the abbreviation.
+  ///
+  void assignAbbrevNumber(DIEAbbrev &Abbrev);
+
+  /// createDIEEntry - Creates a new DIEEntry to be a proxy for a debug
+  /// information entry.
+  DIEEntry *createDIEEntry(DIE *Entry = NULL);
+
+  /// addUInt - Add an unsigned integer attribute data and value.
+  ///
+  void addUInt(DIE *Die, unsigned Attribute, unsigned Form, uint64_t Integer);
+
+  /// addSInt - Add an signed integer attribute data and value.
+  ///
+  void addSInt(DIE *Die, unsigned Attribute, unsigned Form, int64_t Integer);
+
+  /// addString - Add a string attribute data and value.
+  ///
+  void addString(DIE *Die, unsigned Attribute, unsigned Form,
+                 const StringRef Str);
+
+  /// addLabel - Add a Dwarf label attribute data and value.
+  ///
+  void addLabel(DIE *Die, unsigned Attribute, unsigned Form,
+                const DWLabel &Label);
+
+  /// addObjectLabel - Add an non-Dwarf label attribute data and value.
+  ///
+  void addObjectLabel(DIE *Die, unsigned Attribute, unsigned Form,
+                      const MCSymbol *Sym);
+
+  /// addSectionOffset - Add a section offset label attribute data and value.
+  ///
+  void addSectionOffset(DIE *Die, unsigned Attribute, unsigned Form,
+                        const DWLabel &Label, const DWLabel &Section,
+                        bool isEH = false, bool useSet = true);
+
+  /// addDelta - Add a label delta attribute data and value.
+  ///
+  void addDelta(DIE *Die, unsigned Attribute, unsigned Form,
+                const DWLabel &Hi, const DWLabel &Lo);
+
+  /// addDIEEntry - Add a DIE attribute data and value.
+  ///
+  void addDIEEntry(DIE *Die, unsigned Attribute, unsigned Form, DIE *Entry) {
+    Die->addValue(Attribute, Form, createDIEEntry(Entry));
+  }
+
+  /// addBlock - Add block data.
+  ///
+  void addBlock(DIE *Die, unsigned Attribute, unsigned Form, DIEBlock *Block);
+
+  /// addSourceLine - Add location information to specified debug information
+  /// entry.
+  void addSourceLine(DIE *Die, const DIVariable *V);
+  void addSourceLine(DIE *Die, const DIGlobal *G);
+  void addSourceLine(DIE *Die, const DISubprogram *SP);
+  void addSourceLine(DIE *Die, const DIType *Ty);
+  void addSourceLine(DIE *Die, const DINameSpace *NS);
+
+  /// addAddress - Add an address attribute to a die based on the location
+  /// provided.
+  void addAddress(DIE *Die, unsigned Attribute,
+                  const MachineLocation &Location);
+
+  /// addComplexAddress - Start with the address based on the location provided,
+  /// and generate the DWARF information necessary to find the actual variable
+  /// (navigating the extra location information encoded in the type) based on
+  /// the starting location.  Add the DWARF information to the die.
+  ///
+  void addComplexAddress(DbgVariable *&DV, DIE *Die, unsigned Attribute,
+                         const MachineLocation &Location);
+
+  // FIXME: Should be reformulated in terms of addComplexAddress.
+  /// addBlockByrefAddress - Start with the address based on the location
+  /// provided, and generate the DWARF information necessary to find the
+  /// actual Block variable (navigating the Block struct) based on the
+  /// starting location.  Add the DWARF information to the die.  Obsolete,
+  /// please use addComplexAddress instead.
+  ///
+  void addBlockByrefAddress(DbgVariable *&DV, DIE *Die, unsigned Attribute,
+                            const MachineLocation &Location);
+
+  /// addToContextOwner - Add Die into the list of its context owner's children.
+  void addToContextOwner(DIE *Die, DIDescriptor Context);
+
+  /// addType - Add a new type attribute to the specified entity.
+  void addType(DIE *Entity, DIType Ty);
+
+ 
+  /// getOrCreateNameSpace - Create a DIE for DINameSpace.
+  DIE *getOrCreateNameSpace(DINameSpace NS);
+
+  /// getOrCreateTypeDIE - Find existing DIE or create new DIE for the
+  /// given DIType.
+  DIE *getOrCreateTypeDIE(DIType Ty);
+
+  void addPubTypes(DISubprogram SP);
+
+  /// constructTypeDIE - Construct basic type die from DIBasicType.
+  void constructTypeDIE(DIE &Buffer,
+                        DIBasicType BTy);
+
+  /// constructTypeDIE - Construct derived type die from DIDerivedType.
+  void constructTypeDIE(DIE &Buffer,
+                        DIDerivedType DTy);
+
+  /// constructTypeDIE - Construct type DIE from DICompositeType.
+  void constructTypeDIE(DIE &Buffer,
+                        DICompositeType CTy);
+
+  /// constructSubrangeDIE - Construct subrange DIE from DISubrange.
+  void constructSubrangeDIE(DIE &Buffer, DISubrange SR, DIE *IndexTy);
+
+  /// constructArrayTypeDIE - Construct array type DIE from DICompositeType.
+  void constructArrayTypeDIE(DIE &Buffer, 
+                             DICompositeType *CTy);
+
+  /// constructEnumTypeDIE - Construct enum type DIE from DIEnumerator.
+  DIE *constructEnumTypeDIE(DIEnumerator *ETy);
+
+  /// createGlobalVariableDIE - Create new DIE using GV.
+  DIE *createGlobalVariableDIE(const DIGlobalVariable &GV);
+
+  /// createMemberDIE - Create new member DIE.
+  DIE *createMemberDIE(const DIDerivedType &DT);
+
+  /// createSubprogramDIE - Create new DIE using SP.
+  DIE *createSubprogramDIE(const DISubprogram &SP, bool MakeDecl = false);
+
+  /// findCompileUnit - Get the compile unit for the given descriptor. 
+  ///
+  CompileUnit *findCompileUnit(DICompileUnit Unit);
+
+  /// getUpdatedDbgScope - Find or create DbgScope assicated with 
+  /// the instruction. Initialize scope and update scope hierarchy.
+  DbgScope *getUpdatedDbgScope(MDNode *N, const MachineInstr *MI, MDNode *InlinedAt);
+
+  /// createDbgScope - Create DbgScope for the scope.
+  void createDbgScope(MDNode *Scope, MDNode *InlinedAt);
+
+  DbgScope *getOrCreateAbstractScope(MDNode *N);
+
+  /// findAbstractVariable - Find abstract variable associated with Var.
+  DbgVariable *findAbstractVariable(DIVariable &Var, unsigned FrameIdx, 
+                                    DILocation &Loc);
+
+  /// updateSubprogramScopeDIE - Find DIE for the given subprogram and 
+  /// attach appropriate DW_AT_low_pc and DW_AT_high_pc attributes.
+  /// If there are global variables in this scope then create and insert
+  /// DIEs for these variables.
+  DIE *updateSubprogramScopeDIE(MDNode *SPNode);
+
+  /// constructLexicalScope - Construct new DW_TAG_lexical_block 
+  /// for this scope and attach DW_AT_low_pc/DW_AT_high_pc labels.
+  DIE *constructLexicalScopeDIE(DbgScope *Scope);
+
+  /// constructInlinedScopeDIE - This scope represents inlined body of
+  /// a function. Construct DIE to represent this concrete inlined copy
+  /// of the function.
+  DIE *constructInlinedScopeDIE(DbgScope *Scope);
+
+  /// constructVariableDIE - Construct a DIE for the given DbgVariable.
+  DIE *constructVariableDIE(DbgVariable *DV, DbgScope *S);
+
+  /// constructScopeDIE - Construct a DIE for this scope.
+  DIE *constructScopeDIE(DbgScope *Scope);
+
+  /// emitInitial - Emit initial Dwarf declarations.  This is necessary for cc
+  /// tools to recognize the object file contains Dwarf information.
+  void emitInitial();
+
+  /// emitDIE - Recusively Emits a debug information entry.
+  ///
+  void emitDIE(DIE *Die);
+
+  /// computeSizeAndOffset - Compute the size and offset of a DIE.
+  ///
+  unsigned computeSizeAndOffset(DIE *Die, unsigned Offset, bool Last);
+
+  /// computeSizeAndOffsets - Compute the size and offset of all the DIEs.
+  ///
+  void computeSizeAndOffsets();
+
+  /// EmitDebugInfo - Emit the debug info section.
+  ///
+  void emitDebugInfo();
+
+  /// emitAbbreviations - Emit the abbreviation section.
+  ///
+  void emitAbbreviations() const;
+
+  /// emitEndOfLineMatrix - Emit the last address of the section and the end of
+  /// the line matrix.
+  ///
+  void emitEndOfLineMatrix(unsigned SectionEnd);
+
+  /// emitDebugLines - Emit source line information.
+  ///
+  void emitDebugLines();
+
+  /// emitCommonDebugFrame - Emit common frame info into a debug frame section.
+  ///
+  void emitCommonDebugFrame();
+
+  /// emitFunctionDebugFrame - Emit per function frame info into a debug frame
+  /// section.
+  void emitFunctionDebugFrame(const FunctionDebugFrameInfo &DebugFrameInfo);
+
+  /// emitDebugPubNames - Emit visible names into a debug pubnames section.
+  ///
+  void emitDebugPubNames();
+
+  /// emitDebugPubTypes - Emit visible types into a debug pubtypes section.
+  ///
+  void emitDebugPubTypes();
+
+  /// emitDebugStr - Emit visible names into a debug str section.
+  ///
+  void emitDebugStr();
+
+  /// emitDebugLoc - Emit visible names into a debug loc section.
+  ///
+  void emitDebugLoc();
+
+  /// EmitDebugARanges - Emit visible names into a debug aranges section.
+  ///
+  void EmitDebugARanges();
+
+  /// emitDebugRanges - Emit visible names into a debug ranges section.
+  ///
+  void emitDebugRanges();
+
+  /// emitDebugMacInfo - Emit visible names into a debug macinfo section.
+  ///
+  void emitDebugMacInfo();
+
+  /// emitDebugInlineInfo - Emit inline info using following format.
+  /// Section Header:
+  /// 1. length of section
+  /// 2. Dwarf version number
+  /// 3. address size.
+  ///
+  /// Entries (one "entry" for each function that was inlined):
+  ///
+  /// 1. offset into __debug_str section for MIPS linkage name, if exists; 
+  ///   otherwise offset into __debug_str for regular function name.
+  /// 2. offset into __debug_str section for regular function name.
+  /// 3. an unsigned LEB128 number indicating the number of distinct inlining 
+  /// instances for the function.
+  /// 
+  /// The rest of the entry consists of a {die_offset, low_pc}  pair for each 
+  /// inlined instance; the die_offset points to the inlined_subroutine die in
+  /// the __debug_info section, and the low_pc is the starting address  for the
+  ///  inlining instance.
+  void emitDebugInlineInfo();
+
+  /// GetOrCreateSourceID - Look up the source id with the given directory and
+  /// source file names. If none currently exists, create a new id and insert it
+  /// in the SourceIds map. This can update DirectoryNames and SourceFileNames maps
+  /// as well.
+  unsigned GetOrCreateSourceID(StringRef DirName, StringRef FileName);
+
+  CompileUnit *constructCompileUnit(MDNode *N);
+
+  void constructGlobalVariableDIE(MDNode *N);
+
+  void constructSubprogramDIE(MDNode *N);
+
+  // FIXME: This should go away in favor of complex addresses.
+  /// Find the type the programmer originally declared the variable to be
+  /// and return that type.  Obsolete, use GetComplexAddrType instead.
+  ///
+  DIType getBlockByrefType(DIType Ty, std::string Name);
+
+public:
+  //===--------------------------------------------------------------------===//
+  // Main entry points.
+  //
+  DwarfDebug(raw_ostream &OS, AsmPrinter *A, const MCAsmInfo *T);
+  virtual ~DwarfDebug();
+
+  /// ShouldEmitDwarfDebug - Returns true if Dwarf debugging declarations should
+  /// be emitted.
+  bool ShouldEmitDwarfDebug() const { return shouldEmit; }
+
+  /// beginModule - Emit all Dwarf sections that should come prior to the
+  /// content.
+  void beginModule(Module *M, MachineModuleInfo *MMI);
+
+  /// endModule - Emit all Dwarf sections that should come after the content.
+  ///
+  void endModule();
+
+  /// beginFunction - Gather pre-function debug information.  Assumes being
+  /// emitted immediately after the function entry point.
+  void beginFunction(const MachineFunction *MF);
+
+  /// endFunction - Gather and emit post-function debug information.
+  ///
+  void endFunction(const MachineFunction *MF);
+
+  /// recordSourceLine - Records location information and associates it with a 
+  /// label. Returns a unique label ID used to generate a label and provide
+  /// correspondence to the source line list.
+  unsigned recordSourceLine(unsigned Line, unsigned Col, MDNode *Scope);
+
+  /// getSourceLineCount - Return the number of source lines in the debug
+  /// info.
+  unsigned getSourceLineCount() const {
+    return Lines.size();
+  }
+                            
+  /// getOrCreateSourceID - Public version of GetOrCreateSourceID. This can be
+  /// timed. Look up the source id with the given directory and source file
+  /// names. If none currently exists, create a new id and insert it in the
+  /// SourceIds map. This can update DirectoryNames and SourceFileNames maps as
+  /// well.
+  unsigned getOrCreateSourceID(const std::string &DirName,
+                               const std::string &FileName);
+
+  /// extractScopeInformation - Scan machine instructions in this function
+  /// and collect DbgScopes. Return true, if atleast one scope was found.
+  bool extractScopeInformation();
+
+  /// collectVariableInfo - Populate DbgScope entries with variables' info.
+  void collectVariableInfo();
+
+  /// beginScope - Process beginning of a scope starting at Label.
+  void beginScope(const MachineInstr *MI, unsigned Label);
+
+  /// endScope - Prcess end of a scope.
+  void endScope(const MachineInstr *MI);
+};
+} // End of namespace llvm
+
+#endif
diff --git a/lib/CodeGen/AsmPrinter/DwarfException.cpp b/lib/CodeGen/AsmPrinter/DwarfException.cpp
new file mode 100644
index 0000000000..b6801dc61d
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/DwarfException.cpp
@@ -0,0 +1,1021 @@
+//===-- CodeGen/AsmPrinter/DwarfException.cpp - Dwarf Exception Impl ------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for writing DWARF exception info into asm files.
+//
+//===----------------------------------------------------------------------===//
+
+#include "DwarfException.h"
+#include "llvm/Module.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineLocation.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Target/Mangler.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetFrameInfo.h"
+#include "llvm/Target/TargetLoweringObjectFile.h"
+#include "llvm/Target/TargetOptions.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Support/Dwarf.h"
+#include "llvm/Support/FormattedStream.h"
+#include "llvm/Support/Timer.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/Twine.h"
+using namespace llvm;
+
+DwarfException::DwarfException(raw_ostream &OS, AsmPrinter *A,
+                               const MCAsmInfo *T)
+  : DwarfPrinter(OS, A, T, "eh"), shouldEmitTable(false),shouldEmitMoves(false),
+    shouldEmitTableModule(false), shouldEmitMovesModule(false),
+    ExceptionTimer(0) {
+  if (TimePassesIsEnabled)
+    ExceptionTimer = new Timer("DWARF Exception Writer");
+}
+
+DwarfException::~DwarfException() {
+  delete ExceptionTimer;
+}
+
+/// SizeOfEncodedValue - Return the size of the encoding in bytes.
+unsigned DwarfException::SizeOfEncodedValue(unsigned Encoding) {
+  if (Encoding == dwarf::DW_EH_PE_omit)
+    return 0;
+
+  switch (Encoding & 0x07) {
+  case dwarf::DW_EH_PE_absptr:
+    return TD->getPointerSize();
+  case dwarf::DW_EH_PE_udata2:
+    return 2;
+  case dwarf::DW_EH_PE_udata4:
+    return 4;
+  case dwarf::DW_EH_PE_udata8:
+    return 8;
+  }
+
+  assert(0 && "Invalid encoded value.");
+  return 0;
+}
+
+/// CreateLabelDiff - Emit a label and subtract it from the expression we
+/// already have.  This is equivalent to emitting "foo - .", but we have to emit
+/// the label for "." directly.
+const MCExpr *DwarfException::CreateLabelDiff(const MCExpr *ExprRef,
+                                              const char *LabelName,
+                                              unsigned Index) {
+  SmallString<64> Name;
+  raw_svector_ostream(Name) << MAI->getPrivateGlobalPrefix()
+                            << LabelName << Asm->getFunctionNumber()
+                            << "_" << Index;
+  MCSymbol *DotSym = Asm->OutContext.GetOrCreateSymbol(Name.str());
+  Asm->OutStreamer.EmitLabel(DotSym);
+
+  return MCBinaryExpr::CreateSub(ExprRef,
+                                 MCSymbolRefExpr::Create(DotSym,
+                                                         Asm->OutContext),
+                                 Asm->OutContext);
+}
+
+/// EmitCIE - Emit a Common Information Entry (CIE). This holds information that
+/// is shared among many Frame Description Entries.  There is at least one CIE
+/// in every non-empty .debug_frame section.
+void DwarfException::EmitCIE(const Function *PersonalityFn, unsigned Index) {
+  // Size and sign of stack growth.
+  int stackGrowth =
+    Asm->TM.getFrameInfo()->getStackGrowthDirection() ==
+    TargetFrameInfo::StackGrowsUp ?
+    TD->getPointerSize() : -TD->getPointerSize();
+
+  const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
+  
+  // Begin eh frame section.
+  Asm->OutStreamer.SwitchSection(TLOF.getEHFrameSection());
+
+  if (MAI->is_EHSymbolPrivate())
+    O << MAI->getPrivateGlobalPrefix();
+  O << "EH_frame" << Index << ":\n";
+  
+  EmitLabel("section_eh_frame", Index);
+
+  // Define base labels.
+  EmitLabel("eh_frame_common", Index);
+
+  // Define the eh frame length.
+  EmitDifference("eh_frame_common_end", Index,
+                 "eh_frame_common_begin", Index, true);
+  EOL("Length of Common Information Entry");
+
+  // EH frame header.
+  EmitLabel("eh_frame_common_begin", Index);
+  if (Asm->VerboseAsm) Asm->OutStreamer.AddComment("CIE Identifier Tag");
+  Asm->OutStreamer.EmitIntValue(0, 4/*size*/, 0/*addrspace*/);
+  if (Asm->VerboseAsm) Asm->OutStreamer.AddComment("DW_CIE_VERSION");
+  Asm->OutStreamer.EmitIntValue(dwarf::DW_CIE_VERSION, 1/*size*/, 0/*addr*/);
+
+  // The personality presence indicates that language specific information will
+  // show up in the eh frame.  Find out how we are supposed to lower the
+  // personality function reference:
+  const MCExpr *PersonalityRef = 0;
+  bool IsPersonalityIndirect = false, IsPersonalityPCRel = false;
+  if (PersonalityFn) {
+    // FIXME: HANDLE STATIC CODEGEN MODEL HERE.
+    
+    // In non-static mode, ask the object file how to represent this reference.
+    PersonalityRef =
+      TLOF.getSymbolForDwarfGlobalReference(PersonalityFn, Asm->Mang,
+                                            Asm->MMI,
+                                            IsPersonalityIndirect,
+                                            IsPersonalityPCRel);
+  }
+  
+  unsigned PerEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
+  if (IsPersonalityIndirect)
+    PerEncoding |= dwarf::DW_EH_PE_indirect;
+  unsigned LSDAEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
+  unsigned FDEEncoding = dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4;
+
+  char Augmentation[6] = { 0 };
+  unsigned AugmentationSize = 0;
+  char *APtr = Augmentation + 1;
+
+  if (PersonalityRef) {
+    // There is a personality function.
+    *APtr++ = 'P';
+    AugmentationSize += 1 + SizeOfEncodedValue(PerEncoding);
+  }
+
+  if (UsesLSDA[Index]) {
+    // An LSDA pointer is in the FDE augmentation.
+    *APtr++ = 'L';
+    ++AugmentationSize;
+  }
+
+  if (FDEEncoding != dwarf::DW_EH_PE_absptr) {
+    // A non-default pointer encoding for the FDE.
+    *APtr++ = 'R';
+    ++AugmentationSize;
+  }
+
+  if (APtr != Augmentation + 1)
+    Augmentation[0] = 'z';
+
+  Asm->OutStreamer.EmitBytes(StringRef(Augmentation, strlen(Augmentation)+1),0);
+  EOL("CIE Augmentation");
+
+  // Round out reader.
+  EmitULEB128(1, "CIE Code Alignment Factor");
+  EmitSLEB128(stackGrowth, "CIE Data Alignment Factor");
+  Asm->EmitInt8(RI->getDwarfRegNum(RI->getRARegister(), true));
+  EOL("CIE Return Address Column");
+
+  EmitULEB128(AugmentationSize, "Augmentation Size");
+  EmitEncodingByte(PerEncoding, "Personality");
+
+  // If there is a personality, we need to indicate the function's location.
+  if (PersonalityRef) {
+    if (!IsPersonalityPCRel)
+      PersonalityRef = CreateLabelDiff(PersonalityRef, "personalityref_addr",
+                                       Index);
+
+    O << MAI->getData32bitsDirective() << *PersonalityRef;
+    EOL("Personality");
+
+    EmitEncodingByte(LSDAEncoding, "LSDA");
+    EmitEncodingByte(FDEEncoding, "FDE");
+  }
+
+  // Indicate locations of general callee saved registers in frame.
+  std::vector<MachineMove> Moves;
+  RI->getInitialFrameState(Moves);
+  EmitFrameMoves(NULL, 0, Moves, true);
+
+  // On Darwin the linker honors the alignment of eh_frame, which means it must
+  // be 8-byte on 64-bit targets to match what gcc does.  Otherwise you get
+  // holes which confuse readers of eh_frame.
+  Asm->EmitAlignment(TD->getPointerSize() == 4 ? 2 : 3, 0, 0, false);
+  EmitLabel("eh_frame_common_end", Index);
+  Asm->O << '\n';
+}
+
+/// EmitFDE - Emit the Frame Description Entry (FDE) for the function.
+void DwarfException::EmitFDE(const FunctionEHFrameInfo &EHFrameInfo) {
+  assert(!EHFrameInfo.function->hasAvailableExternallyLinkage() &&
+         "Should not emit 'available externally' functions at all");
+
+  const Function *TheFunc = EHFrameInfo.function;
+
+  Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering().getEHFrameSection());
+
+  // Externally visible entry into the functions eh frame info. If the
+  // corresponding function is static, this should not be externally visible.
+  if (!TheFunc->hasLocalLinkage())
+    if (const char *GlobalEHDirective = MAI->getGlobalEHDirective())
+      O << GlobalEHDirective << *EHFrameInfo.FunctionEHSym << '\n';
+
+  // If corresponding function is weak definition, this should be too.
+  if (TheFunc->isWeakForLinker() && MAI->getWeakDefDirective())
+    O << MAI->getWeakDefDirective() << *EHFrameInfo.FunctionEHSym << '\n';
+
+  // If corresponding function is hidden, this should be too.
+  if (TheFunc->hasHiddenVisibility())
+    if (MCSymbolAttr HiddenAttr = MAI->getHiddenVisibilityAttr())
+      Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
+                                           HiddenAttr);
+
+  // If there are no calls then you can't unwind.  This may mean we can omit the
+  // EH Frame, but some environments do not handle weak absolute symbols. If
+  // UnwindTablesMandatory is set we cannot do this optimization; the unwind
+  // info is to be available for non-EH uses.
+  if (!EHFrameInfo.hasCalls && !UnwindTablesMandatory &&
+      (!TheFunc->isWeakForLinker() ||
+       !MAI->getWeakDefDirective() ||
+       MAI->getSupportsWeakOmittedEHFrame())) {
+    O << *EHFrameInfo.FunctionEHSym << " = 0\n";
+    // This name has no connection to the function, so it might get
+    // dead-stripped when the function is not, erroneously.  Prohibit
+    // dead-stripping unconditionally.
+    if (MAI->hasNoDeadStrip())
+      Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
+                                           MCSA_NoDeadStrip);
+  } else {
+    O << *EHFrameInfo.FunctionEHSym << ":\n";
+
+    // EH frame header.
+    EmitDifference("eh_frame_end", EHFrameInfo.Number,
+                   "eh_frame_begin", EHFrameInfo.Number, true);
+    EOL("Length of Frame Information Entry");
+
+    EmitLabel("eh_frame_begin", EHFrameInfo.Number);
+
+    EmitSectionOffset("eh_frame_begin", "eh_frame_common",
+                      EHFrameInfo.Number, EHFrameInfo.PersonalityIndex,
+                      true, true, false);
+
+    EOL("FDE CIE offset");
+
+    EmitReference("eh_func_begin", EHFrameInfo.Number, true, true);
+    EOL("FDE initial location");
+    EmitDifference("eh_func_end", EHFrameInfo.Number,
+                   "eh_func_begin", EHFrameInfo.Number, true);
+    EOL("FDE address range");
+
+    // If there is a personality and landing pads then point to the language
+    // specific data area in the exception table.
+    if (MMI->getPersonalities()[0] != NULL) {
+
+      if (Asm->TM.getLSDAEncoding() != DwarfLSDAEncoding::EightByte) {
+        EmitULEB128(4, "Augmentation size");
+
+        if (EHFrameInfo.hasLandingPads)
+          EmitReference("exception", EHFrameInfo.Number, true, true);
+        else
+          Asm->OutStreamer.EmitIntValue(0, 4/*size*/, 0/*addrspace*/);
+      } else {
+        EmitULEB128(TD->getPointerSize(), "Augmentation size");
+
+        if (EHFrameInfo.hasLandingPads) {
+          EmitReference("exception", EHFrameInfo.Number, true, false);
+        } else {
+          Asm->OutStreamer.EmitIntValue(0, TD->getPointerSize(),
+                                        0/*addrspace*/);
+        }
+      }
+
+      EOL("Language Specific Data Area");
+    } else {
+      EmitULEB128(0, "Augmentation size");
+    }
+
+    // Indicate locations of function specific callee saved registers in frame.
+    EmitFrameMoves("eh_func_begin", EHFrameInfo.Number, EHFrameInfo.Moves,
+                   true);
+
+    // On Darwin the linker honors the alignment of eh_frame, which means it
+    // must be 8-byte on 64-bit targets to match what gcc does.  Otherwise you
+    // get holes which confuse readers of eh_frame.
+    Asm->EmitAlignment(TD->getPointerSize() == sizeof(int32_t) ? 2 : 3,
+                       0, 0, false);
+    EmitLabel("eh_frame_end", EHFrameInfo.Number);
+
+    // If the function is marked used, this table should be also.  We cannot
+    // make the mark unconditional in this case, since retaining the table also
+    // retains the function in this case, and there is code around that depends
+    // on unused functions (calling undefined externals) being dead-stripped to
+    // link correctly.  Yes, there really is.
+    if (MMI->isUsedFunction(EHFrameInfo.function))
+      if (MAI->hasNoDeadStrip())
+        Asm->OutStreamer.EmitSymbolAttribute(EHFrameInfo.FunctionEHSym,
+                                             MCSA_NoDeadStrip);
+  }
+  Asm->O << '\n';
+}
+
+/// SharedTypeIds - How many leading type ids two landing pads have in common.
+unsigned DwarfException::SharedTypeIds(const LandingPadInfo *L,
+                                       const LandingPadInfo *R) {
+  const std::vector<int> &LIds = L->TypeIds, &RIds = R->TypeIds;
+  unsigned LSize = LIds.size(), RSize = RIds.size();
+  unsigned MinSize = LSize < RSize ? LSize : RSize;
+  unsigned Count = 0;
+
+  for (; Count != MinSize; ++Count)
+    if (LIds[Count] != RIds[Count])
+      return Count;
+
+  return Count;
+}
+
+/// PadLT - Order landing pads lexicographically by type id.
+bool DwarfException::PadLT(const LandingPadInfo *L, const LandingPadInfo *R) {
+  const std::vector<int> &LIds = L->TypeIds, &RIds = R->TypeIds;
+  unsigned LSize = LIds.size(), RSize = RIds.size();
+  unsigned MinSize = LSize < RSize ? LSize : RSize;
+
+  for (unsigned i = 0; i != MinSize; ++i)
+    if (LIds[i] != RIds[i])
+      return LIds[i] < RIds[i];
+
+  return LSize < RSize;
+}
+
+/// ComputeActionsTable - Compute the actions table and gather the first action
+/// index for each landing pad site.
+unsigned DwarfException::
+ComputeActionsTable(const SmallVectorImpl<const LandingPadInfo*> &LandingPads,
+                    SmallVectorImpl<ActionEntry> &Actions,
+                    SmallVectorImpl<unsigned> &FirstActions) {
+
+  // The action table follows the call-site table in the LSDA. The individual
+  // records are of two types:
+  //
+  //   * Catch clause
+  //   * Exception specification
+  //
+  // The two record kinds have the same format, with only small differences.
+  // They are distinguished by the "switch value" field: Catch clauses
+  // (TypeInfos) have strictly positive switch values, and exception
+  // specifications (FilterIds) have strictly negative switch values. Value 0
+  // indicates a catch-all clause.
+  //
+  // Negative type IDs index into FilterIds. Positive type IDs index into
+  // TypeInfos.  The value written for a positive type ID is just the type ID
+  // itself.  For a negative type ID, however, the value written is the
+  // (negative) byte offset of the corresponding FilterIds entry.  The byte
+  // offset is usually equal to the type ID (because the FilterIds entries are
+  // written using a variable width encoding, which outputs one byte per entry
+  // as long as the value written is not too large) but can differ.  This kind
+  // of complication does not occur for positive type IDs because type infos are
+  // output using a fixed width encoding.  FilterOffsets[i] holds the byte
+  // offset corresponding to FilterIds[i].
+
+  const std::vector<unsigned> &FilterIds = MMI->getFilterIds();
+  SmallVector<int, 16> FilterOffsets;
+  FilterOffsets.reserve(FilterIds.size());
+  int Offset = -1;
+
+  for (std::vector<unsigned>::const_iterator
+         I = FilterIds.begin(), E = FilterIds.end(); I != E; ++I) {
+    FilterOffsets.push_back(Offset);
+    Offset -= MCAsmInfo::getULEB128Size(*I);
+  }
+
+  FirstActions.reserve(LandingPads.size());
+
+  int FirstAction = 0;
+  unsigned SizeActions = 0;
+  const LandingPadInfo *PrevLPI = 0;
+
+  for (SmallVectorImpl<const LandingPadInfo *>::const_iterator
+         I = LandingPads.begin(), E = LandingPads.end(); I != E; ++I) {
+    const LandingPadInfo *LPI = *I;
+    const std::vector<int> &TypeIds = LPI->TypeIds;
+    const unsigned NumShared = PrevLPI ? SharedTypeIds(LPI, PrevLPI) : 0;
+    unsigned SizeSiteActions = 0;
+
+    if (NumShared < TypeIds.size()) {
+      unsigned SizeAction = 0;
+      ActionEntry *PrevAction = 0;
+
+      if (NumShared) {
+        const unsigned SizePrevIds = PrevLPI->TypeIds.size();
+        assert(Actions.size());
+        PrevAction = &Actions.back();
+        SizeAction = MCAsmInfo::getSLEB128Size(PrevAction->NextAction) +
+          MCAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID);
+
+        for (unsigned j = NumShared; j != SizePrevIds; ++j) {
+          SizeAction -=
+            MCAsmInfo::getSLEB128Size(PrevAction->ValueForTypeID);
+          SizeAction += -PrevAction->NextAction;
+          PrevAction = PrevAction->Previous;
+        }
+      }
+
+      // Compute the actions.
+      for (unsigned J = NumShared, M = TypeIds.size(); J != M; ++J) {
+        int TypeID = TypeIds[J];
+        assert(-1 - TypeID < (int)FilterOffsets.size() && "Unknown filter id!");
+        int ValueForTypeID = TypeID < 0 ? FilterOffsets[-1 - TypeID] : TypeID;
+        unsigned SizeTypeID = MCAsmInfo::getSLEB128Size(ValueForTypeID);
+
+        int NextAction = SizeAction ? -(SizeAction + SizeTypeID) : 0;
+        SizeAction = SizeTypeID + MCAsmInfo::getSLEB128Size(NextAction);
+        SizeSiteActions += SizeAction;
+
+        ActionEntry Action = { ValueForTypeID, NextAction, PrevAction };
+        Actions.push_back(Action);
+        PrevAction = &Actions.back();
+      }
+
+      // Record the first action of the landing pad site.
+      FirstAction = SizeActions + SizeSiteActions - SizeAction + 1;
+    } // else identical - re-use previous FirstAction
+
+    // Information used when created the call-site table. The action record
+    // field of the call site record is the offset of the first associated
+    // action record, relative to the start of the actions table. This value is
+    // biased by 1 (1 in dicating the start of the actions table), and 0
+    // indicates that there are no actions.
+    FirstActions.push_back(FirstAction);
+
+    // Compute this sites contribution to size.
+    SizeActions += SizeSiteActions;
+
+    PrevLPI = LPI;
+  }
+
+  return SizeActions;
+}
+
+/// CallToNoUnwindFunction - Return `true' if this is a call to a function
+/// marked `nounwind'. Return `false' otherwise.
+bool DwarfException::CallToNoUnwindFunction(const MachineInstr *MI) {
+  assert(MI->getDesc().isCall() && "This should be a call instruction!");
+
+  bool MarkedNoUnwind = false;
+  bool SawFunc = false;
+
+  for (unsigned I = 0, E = MI->getNumOperands(); I != E; ++I) {
+    const MachineOperand &MO = MI->getOperand(I);
+
+    if (MO.isGlobal()) {
+      if (Function *F = dyn_cast<Function>(MO.getGlobal())) {
+        if (SawFunc) {
+          // Be conservative. If we have more than one function operand for this
+          // call, then we can't make the assumption that it's the callee and
+          // not a parameter to the call.
+          // 
+          // FIXME: Determine if there's a way to say that `F' is the callee or
+          // parameter.
+          MarkedNoUnwind = false;
+          break;
+        }
+
+        MarkedNoUnwind = F->doesNotThrow();
+        SawFunc = true;
+      }
+    }
+  }
+
+  return MarkedNoUnwind;
+}
+
+/// ComputeCallSiteTable - Compute the call-site table.  The entry for an invoke
+/// has a try-range containing the call, a non-zero landing pad, and an
+/// appropriate action.  The entry for an ordinary call has a try-range
+/// containing the call and zero for the landing pad and the action.  Calls
+/// marked 'nounwind' have no entry and must not be contained in the try-range
+/// of any entry - they form gaps in the table.  Entries must be ordered by
+/// try-range address.
+void DwarfException::
+ComputeCallSiteTable(SmallVectorImpl<CallSiteEntry> &CallSites,
+                     const RangeMapType &PadMap,
+                     const SmallVectorImpl<const LandingPadInfo *> &LandingPads,
+                     const SmallVectorImpl<unsigned> &FirstActions) {
+  // The end label of the previous invoke or nounwind try-range.
+  unsigned LastLabel = 0;
+
+  // Whether there is a potentially throwing instruction (currently this means
+  // an ordinary call) between the end of the previous try-range and now.
+  bool SawPotentiallyThrowing = false;
+
+  // Whether the last CallSite entry was for an invoke.
+  bool PreviousIsInvoke = false;
+
+  // Visit all instructions in order of address.
+  for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
+       I != E; ++I) {
+    for (MachineBasicBlock::const_iterator MI = I->begin(), E = I->end();
+         MI != E; ++MI) {
+      if (!MI->isLabel()) {
+        if (MI->getDesc().isCall())
+          SawPotentiallyThrowing |= !CallToNoUnwindFunction(MI);
+
+        continue;
+      }
+
+      unsigned BeginLabel = MI->getOperand(0).getImm();
+      assert(BeginLabel && "Invalid label!");
+
+      // End of the previous try-range?
+      if (BeginLabel == LastLabel)
+        SawPotentiallyThrowing = false;
+
+      // Beginning of a new try-range?
+      RangeMapType::const_iterator L = PadMap.find(BeginLabel);
+      if (L == PadMap.end())
+        // Nope, it was just some random label.
+        continue;
+
+      const PadRange &P = L->second;
+      const LandingPadInfo *LandingPad = LandingPads[P.PadIndex];
+      assert(BeginLabel == LandingPad->BeginLabels[P.RangeIndex] &&
+             "Inconsistent landing pad map!");
+
+      // For Dwarf exception handling (SjLj handling doesn't use this). If some
+      // instruction between the previous try-range and this one may throw,
+      // create a call-site entry with no landing pad for the region between the
+      // try-ranges.
+      if (SawPotentiallyThrowing &&
+          MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf) {
+        CallSiteEntry Site = { LastLabel, BeginLabel, 0, 0 };
+        CallSites.push_back(Site);
+        PreviousIsInvoke = false;
+      }
+
+      LastLabel = LandingPad->EndLabels[P.RangeIndex];
+      assert(BeginLabel && LastLabel && "Invalid landing pad!");
+
+      if (LandingPad->LandingPadLabel) {
+        // This try-range is for an invoke.
+        CallSiteEntry Site = {
+          BeginLabel,
+          LastLabel,
+          LandingPad->LandingPadLabel,
+          FirstActions[P.PadIndex]
+        };
+
+        // Try to merge with the previous call-site. SJLJ doesn't do this
+        if (PreviousIsInvoke &&
+          MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf) {
+          CallSiteEntry &Prev = CallSites.back();
+          if (Site.PadLabel == Prev.PadLabel && Site.Action == Prev.Action) {
+            // Extend the range of the previous entry.
+            Prev.EndLabel = Site.EndLabel;
+            continue;
+          }
+        }
+
+        // Otherwise, create a new call-site.
+        if (MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf)
+          CallSites.push_back(Site);
+        else {
+          // SjLj EH must maintain the call sites in the order assigned
+          // to them by the SjLjPrepare pass.
+          unsigned SiteNo = MMI->getCallSiteBeginLabel(BeginLabel);
+          if (CallSites.size() < SiteNo)
+            CallSites.resize(SiteNo);
+          CallSites[SiteNo - 1] = Site;
+        }
+        PreviousIsInvoke = true;
+      } else {
+        // Create a gap.
+        PreviousIsInvoke = false;
+      }
+    }
+  }
+
+  // If some instruction between the previous try-range and the end of the
+  // function may throw, create a call-site entry with no landing pad for the
+  // region following the try-range.
+  if (SawPotentiallyThrowing &&
+      MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf) {
+    CallSiteEntry Site = { LastLabel, 0, 0, 0 };
+    CallSites.push_back(Site);
+  }
+}
+
+/// EmitExceptionTable - Emit landing pads and actions.
+///
+/// The general organization of the table is complex, but the basic concepts are
+/// easy.  First there is a header which describes the location and organization
+/// of the three components that follow.
+///
+///  1. The landing pad site information describes the range of code covered by
+///     the try.  In our case it's an accumulation of the ranges covered by the
+///     invokes in the try.  There is also a reference to the landing pad that
+///     handles the exception once processed.  Finally an index into the actions
+///     table.
+///  2. The action table, in our case, is composed of pairs of type IDs and next
+///     action offset.  Starting with the action index from the landing pad
+///     site, each type ID is checked for a match to the current exception.  If
+///     it matches then the exception and type id are passed on to the landing
+///     pad.  Otherwise the next action is looked up.  This chain is terminated
+///     with a next action of zero.  If no type id is found then the frame is
+///     unwound and handling continues.
+///  3. Type ID table contains references to all the C++ typeinfo for all
+///     catches in the function.  This tables is reverse indexed base 1.
+void DwarfException::EmitExceptionTable() {
+  const std::vector<GlobalVariable *> &TypeInfos = MMI->getTypeInfos();
+  const std::vector<unsigned> &FilterIds = MMI->getFilterIds();
+  const std::vector<LandingPadInfo> &PadInfos = MMI->getLandingPads();
+  if (PadInfos.empty()) return;
+
+  // Sort the landing pads in order of their type ids.  This is used to fold
+  // duplicate actions.
+  SmallVector<const LandingPadInfo *, 64> LandingPads;
+  LandingPads.reserve(PadInfos.size());
+
+  for (unsigned i = 0, N = PadInfos.size(); i != N; ++i)
+    LandingPads.push_back(&PadInfos[i]);
+
+  std::sort(LandingPads.begin(), LandingPads.end(), PadLT);
+
+  // Compute the actions table and gather the first action index for each
+  // landing pad site.
+  SmallVector<ActionEntry, 32> Actions;
+  SmallVector<unsigned, 64> FirstActions;
+  unsigned SizeActions = ComputeActionsTable(LandingPads, Actions,
+                                             FirstActions);
+
+  // Invokes and nounwind calls have entries in PadMap (due to being bracketed
+  // by try-range labels when lowered).  Ordinary calls do not, so appropriate
+  // try-ranges for them need be deduced when using DWARF exception handling.
+  RangeMapType PadMap;
+  for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) {
+    const LandingPadInfo *LandingPad = LandingPads[i];
+    for (unsigned j = 0, E = LandingPad->BeginLabels.size(); j != E; ++j) {
+      unsigned BeginLabel = LandingPad->BeginLabels[j];
+      assert(!PadMap.count(BeginLabel) && "Duplicate landing pad labels!");
+      PadRange P = { i, j };
+      PadMap[BeginLabel] = P;
+    }
+  }
+
+  // Compute the call-site table.
+  SmallVector<CallSiteEntry, 64> CallSites;
+  ComputeCallSiteTable(CallSites, PadMap, LandingPads, FirstActions);
+
+  // Final tallies.
+
+  // Call sites.
+  const unsigned SiteStartSize  = SizeOfEncodedValue(dwarf::DW_EH_PE_udata4);
+  const unsigned SiteLengthSize = SizeOfEncodedValue(dwarf::DW_EH_PE_udata4);
+  const unsigned LandingPadSize = SizeOfEncodedValue(dwarf::DW_EH_PE_udata4);
+  bool IsSJLJ = MAI->getExceptionHandlingType() == ExceptionHandling::SjLj;
+  bool HaveTTData = IsSJLJ ? (!TypeInfos.empty() || !FilterIds.empty()) : true;
+  unsigned SizeSites;
+
+  if (IsSJLJ)
+    SizeSites = 0;
+  else
+    SizeSites = CallSites.size() *
+      (SiteStartSize + SiteLengthSize + LandingPadSize);
+
+  for (unsigned i = 0, e = CallSites.size(); i < e; ++i) {
+    SizeSites += MCAsmInfo::getULEB128Size(CallSites[i].Action);
+    if (IsSJLJ)
+      SizeSites += MCAsmInfo::getULEB128Size(i);
+  }
+
+  // Type infos.
+  const MCSection *LSDASection = Asm->getObjFileLowering().getLSDASection();
+  unsigned TTypeFormat;
+  unsigned TypeFormatSize;
+
+  if (!HaveTTData) {
+    // For SjLj exceptions, if there is no TypeInfo, then we just explicitly say
+    // that we're omitting that bit.
+    TTypeFormat = dwarf::DW_EH_PE_omit;
+    TypeFormatSize = SizeOfEncodedValue(dwarf::DW_EH_PE_absptr);
+  } else {
+    // Okay, we have actual filters or typeinfos to emit.  As such, we need to
+    // pick a type encoding for them.  We're about to emit a list of pointers to
+    // typeinfo objects at the end of the LSDA.  However, unless we're in static
+    // mode, this reference will require a relocation by the dynamic linker.
+    //
+    // Because of this, we have a couple of options:
+    // 
+    //   1) If we are in -static mode, we can always use an absolute reference
+    //      from the LSDA, because the static linker will resolve it.
+    //      
+    //   2) Otherwise, if the LSDA section is writable, we can output the direct
+    //      reference to the typeinfo and allow the dynamic linker to relocate
+    //      it.  Since it is in a writable section, the dynamic linker won't
+    //      have a problem.
+    //      
+    //   3) Finally, if we're in PIC mode and the LDSA section isn't writable,
+    //      we need to use some form of indirection.  For example, on Darwin,
+    //      we can output a statically-relocatable reference to a dyld stub. The
+    //      offset to the stub is constant, but the contents are in a section
+    //      that is updated by the dynamic linker.  This is easy enough, but we
+    //      need to tell the personality function of the unwinder to indirect
+    //      through the dyld stub.
+    //
+    // FIXME: When (3) is actually implemented, we'll have to emit the stubs
+    // somewhere.  This predicate should be moved to a shared location that is
+    // in target-independent code.
+    //
+    if (LSDASection->getKind().isWriteable() ||
+        Asm->TM.getRelocationModel() == Reloc::Static)
+      TTypeFormat = dwarf::DW_EH_PE_absptr;
+    else
+      TTypeFormat = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+        dwarf::DW_EH_PE_sdata4;
+
+    TypeFormatSize = SizeOfEncodedValue(TTypeFormat);
+  }
+
+  // Begin the exception table.
+  Asm->OutStreamer.SwitchSection(LSDASection);
+  Asm->EmitAlignment(2, 0, 0, false);
+
+  O << "GCC_except_table" << SubprogramCount << ":\n";
+
+  // The type infos need to be aligned. GCC does this by inserting padding just
+  // before the type infos. However, this changes the size of the exception
+  // table, so you need to take this into account when you output the exception
+  // table size. However, the size is output using a variable length encoding.
+  // So by increasing the size by inserting padding, you may increase the number
+  // of bytes used for writing the size. If it increases, say by one byte, then
+  // you now need to output one less byte of padding to get the type infos
+  // aligned.  However this decreases the size of the exception table. This
+  // changes the value you have to output for the exception table size. Due to
+  // the variable length encoding, the number of bytes used for writing the
+  // length may decrease. If so, you then have to increase the amount of
+  // padding. And so on. If you look carefully at the GCC code you will see that
+  // it indeed does this in a loop, going on and on until the values stabilize.
+  // We chose another solution: don't output padding inside the table like GCC
+  // does, instead output it before the table.
+  unsigned SizeTypes = TypeInfos.size() * TypeFormatSize;
+  unsigned TyOffset = sizeof(int8_t) +          // Call site format
+    MCAsmInfo::getULEB128Size(SizeSites) +      // Call site table length
+    SizeSites + SizeActions + SizeTypes;
+  unsigned TotalSize = sizeof(int8_t) +         // LPStart format
+                       sizeof(int8_t) +         // TType format
+    (HaveTTData ?
+     MCAsmInfo::getULEB128Size(TyOffset) : 0) + // TType base offset
+    TyOffset;
+  unsigned SizeAlign = (4 - TotalSize) & 3;
+
+  for (unsigned i = 0; i != SizeAlign; ++i) {
+    Asm->EmitInt8(0);
+    EOL("Padding");
+  }
+
+  EmitLabel("exception", SubprogramCount);
+
+  if (IsSJLJ) {
+    SmallString<16> LSDAName;
+    raw_svector_ostream(LSDAName) << MAI->getPrivateGlobalPrefix() <<
+      "_LSDA_" << Asm->getFunctionNumber();
+    O << LSDAName.str() << ":\n";
+  }
+
+  // Emit the header.
+  EmitEncodingByte(dwarf::DW_EH_PE_omit, "@LPStart");
+  EmitEncodingByte(TTypeFormat, "@TType");
+
+  if (HaveTTData)
+    EmitULEB128(TyOffset, "@TType base offset");
+
+  // SjLj Exception handling
+  if (IsSJLJ) {
+    EmitEncodingByte(dwarf::DW_EH_PE_udata4, "Call site");
+    EmitULEB128(SizeSites, "Call site table length");
+
+    // Emit the landing pad site information.
+    unsigned idx = 0;
+    for (SmallVectorImpl<CallSiteEntry>::const_iterator
+         I = CallSites.begin(), E = CallSites.end(); I != E; ++I, ++idx) {
+      const CallSiteEntry &S = *I;
+
+      // Offset of the landing pad, counted in 16-byte bundles relative to the
+      // @LPStart address.
+      EmitULEB128(idx, "Landing pad");
+
+      // Offset of the first associated action record, relative to the start of
+      // the action table. This value is biased by 1 (1 indicates the start of
+      // the action table), and 0 indicates that there are no actions.
+      EmitULEB128(S.Action, "Action");
+    }
+  } else {
+    // DWARF Exception handling
+    assert(MAI->getExceptionHandlingType() == ExceptionHandling::Dwarf);
+
+    // The call-site table is a list of all call sites that may throw an
+    // exception (including C++ 'throw' statements) in the procedure
+    // fragment. It immediately follows the LSDA header. Each entry indicates,
+    // for a given call, the first corresponding action record and corresponding
+    // landing pad.
+    //
+    // The table begins with the number of bytes, stored as an LEB128
+    // compressed, unsigned integer. The records immediately follow the record
+    // count. They are sorted in increasing call-site address. Each record
+    // indicates:
+    //
+    //   * The position of the call-site.
+    //   * The position of the landing pad.
+    //   * The first action record for that call site.
+    //
+    // A missing entry in the call-site table indicates that a call is not
+    // supposed to throw.
+
+    // Emit the landing pad call site table.
+    EmitEncodingByte(dwarf::DW_EH_PE_udata4, "Call site");
+    EmitULEB128(SizeSites, "Call site table length");
+
+    for (SmallVectorImpl<CallSiteEntry>::const_iterator
+         I = CallSites.begin(), E = CallSites.end(); I != E; ++I) {
+      const CallSiteEntry &S = *I;
+      const char *BeginTag;
+      unsigned BeginNumber;
+
+      if (!S.BeginLabel) {
+        BeginTag = "eh_func_begin";
+        BeginNumber = SubprogramCount;
+      } else {
+        BeginTag = "label";
+        BeginNumber = S.BeginLabel;
+      }
+
+      // Offset of the call site relative to the previous call site, counted in
+      // number of 16-byte bundles. The first call site is counted relative to
+      // the start of the procedure fragment.
+      EmitSectionOffset(BeginTag, "eh_func_begin", BeginNumber, SubprogramCount,
+                        true, true);
+      EOL("Region start");
+
+      if (!S.EndLabel)
+        EmitDifference("eh_func_end", SubprogramCount, BeginTag, BeginNumber,
+                       true);
+      else
+        EmitDifference("label", S.EndLabel, BeginTag, BeginNumber, true);
+
+      EOL("Region length");
+
+      // Offset of the landing pad, counted in 16-byte bundles relative to the
+      // @LPStart address.
+      if (!S.PadLabel) {
+        Asm->OutStreamer.AddComment("Landing pad");
+        Asm->OutStreamer.EmitIntValue(0, 4/*size*/, 0/*addrspace*/);
+      } else {
+        EmitSectionOffset("label", "eh_func_begin", S.PadLabel, SubprogramCount,
+                          true, true);
+        EOL("Landing pad");
+      }
+
+      // Offset of the first associated action record, relative to the start of
+      // the action table. This value is biased by 1 (1 indicates the start of
+      // the action table), and 0 indicates that there are no actions.
+      EmitULEB128(S.Action, "Action");
+    }
+  }
+
+  // Emit the Action Table.
+  if (Actions.size() != 0) EOL("-- Action Record Table --");
+  for (SmallVectorImpl<ActionEntry>::const_iterator
+         I = Actions.begin(), E = Actions.end(); I != E; ++I) {
+    const ActionEntry &Action = *I;
+    EOL("Action Record:");
+
+    // Type Filter
+    //
+    //   Used by the runtime to match the type of the thrown exception to the
+    //   type of the catch clauses or the types in the exception specification.
+    EmitSLEB128(Action.ValueForTypeID, "  TypeInfo index");
+
+    // Action Record
+    //
+    //   Self-relative signed displacement in bytes of the next action record,
+    //   or 0 if there is no next action record.
+    EmitSLEB128(Action.NextAction, "  Next action");
+  }
+
+  // Emit the Catch TypeInfos.
+  if (TypeInfos.size() != 0) EOL("-- Catch TypeInfos --");
+  for (std::vector<GlobalVariable *>::const_reverse_iterator
+         I = TypeInfos.rbegin(), E = TypeInfos.rend(); I != E; ++I) {
+    const GlobalVariable *GV = *I;
+    PrintRelDirective();
+
+    if (GV) {
+      O << *Asm->GetGlobalValueSymbol(GV);
+      EOL("TypeInfo");
+    } else {
+      O << "0x0";
+      EOL("");
+    }
+  }
+
+  // Emit the Exception Specifications.
+  if (FilterIds.size() != 0) EOL("-- Filter IDs --");
+  for (std::vector<unsigned>::const_iterator
+         I = FilterIds.begin(), E = FilterIds.end(); I < E; ++I) {
+    unsigned TypeID = *I;
+    EmitULEB128(TypeID, TypeID != 0 ? "Exception specification" : 0);
+  }
+
+  Asm->EmitAlignment(2, 0, 0, false);
+}
+
+/// EndModule - Emit all exception information that should come after the
+/// content.
+void DwarfException::EndModule() {
+  if (MAI->getExceptionHandlingType() != ExceptionHandling::Dwarf)
+    return;
+
+  if (!shouldEmitMovesModule && !shouldEmitTableModule)
+    return;
+
+  if (TimePassesIsEnabled)
+    ExceptionTimer->startTimer();
+
+  const std::vector<Function *> Personalities = MMI->getPersonalities();
+
+  for (unsigned I = 0, E = Personalities.size(); I < E; ++I)
+    EmitCIE(Personalities[I], I);
+
+  for (std::vector<FunctionEHFrameInfo>::iterator
+         I = EHFrames.begin(), E = EHFrames.end(); I != E; ++I)
+    EmitFDE(*I);
+
+  if (TimePassesIsEnabled)
+    ExceptionTimer->stopTimer();
+}
+
+/// BeginFunction - Gather pre-function exception information. Assumes it's
+/// being emitted immediately after the function entry point.
+void DwarfException::BeginFunction(const MachineFunction *MF) {
+  if (!MMI || !MAI->doesSupportExceptionHandling()) return;
+
+  if (TimePassesIsEnabled)
+    ExceptionTimer->startTimer();
+
+  this->MF = MF;
+  shouldEmitTable = shouldEmitMoves = false;
+
+  // Map all labels and get rid of any dead landing pads.
+  MMI->TidyLandingPads();
+
+  // If any landing pads survive, we need an EH table.
+  if (!MMI->getLandingPads().empty())
+    shouldEmitTable = true;
+
+  // See if we need frame move info.
+  if (!MF->getFunction()->doesNotThrow() || UnwindTablesMandatory)
+    shouldEmitMoves = true;
+
+  if (shouldEmitMoves || shouldEmitTable)
+    // Assumes in correct section after the entry point.
+    EmitLabel("eh_func_begin", ++SubprogramCount);
+
+  shouldEmitTableModule |= shouldEmitTable;
+  shouldEmitMovesModule |= shouldEmitMoves;
+
+  if (TimePassesIsEnabled)
+    ExceptionTimer->stopTimer();
+}
+
+/// EndFunction - Gather and emit post-function exception information.
+///
+void DwarfException::EndFunction() {
+  if (!shouldEmitMoves && !shouldEmitTable) return;
+
+  if (TimePassesIsEnabled)
+    ExceptionTimer->startTimer();
+
+  EmitLabel("eh_func_end", SubprogramCount);
+  EmitExceptionTable();
+
+  MCSymbol *FunctionEHSym =
+    Asm->GetSymbolWithGlobalValueBase(MF->getFunction(), ".eh",
+                                      Asm->MAI->is_EHSymbolPrivate());
+  
+  // Save EH frame information
+  EHFrames.push_back(FunctionEHFrameInfo(FunctionEHSym, SubprogramCount,
+                                         MMI->getPersonalityIndex(),
+                                         MF->getFrameInfo()->hasCalls(),
+                                         !MMI->getLandingPads().empty(),
+                                         MMI->getFrameMoves(),
+                                         MF->getFunction()));
+
+  // Record if this personality index uses a landing pad.
+  UsesLSDA[MMI->getPersonalityIndex()] |= !MMI->getLandingPads().empty();
+
+  if (TimePassesIsEnabled)
+    ExceptionTimer->stopTimer();
+}
diff --git a/lib/CodeGen/AsmPrinter/DwarfException.h b/lib/CodeGen/AsmPrinter/DwarfException.h
new file mode 100644
index 0000000000..06033a1a6f
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/DwarfException.h
@@ -0,0 +1,208 @@
+//===-- DwarfException.h - Dwarf Exception Framework -----------*- C++ -*--===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for writing dwarf exception info into asm files.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_ASMPRINTER_DWARFEXCEPTION_H
+#define LLVM_CODEGEN_ASMPRINTER_DWARFEXCEPTION_H
+
+#include "DIE.h"
+#include "DwarfPrinter.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/ADT/DenseMap.h"
+#include <string>
+
+namespace llvm {
+
+struct LandingPadInfo;
+class MachineModuleInfo;
+class MCAsmInfo;
+class MCExpr;
+class Timer;
+class raw_ostream;
+
+//===----------------------------------------------------------------------===//
+/// DwarfException - Emits Dwarf exception handling directives.
+///
+class DwarfException : public DwarfPrinter {
+  struct FunctionEHFrameInfo {
+    MCSymbol *FunctionEHSym;  // L_foo.eh
+    unsigned Number;
+    unsigned PersonalityIndex;
+    bool hasCalls;
+    bool hasLandingPads;
+    std::vector<MachineMove> Moves;
+    const Function *function;
+
+    FunctionEHFrameInfo(MCSymbol *EHSym, unsigned Num, unsigned P,
+                        bool hC, bool hL,
+                        const std::vector<MachineMove> &M,
+                        const Function *f):
+      FunctionEHSym(EHSym), Number(Num), PersonalityIndex(P),
+      hasCalls(hC), hasLandingPads(hL), Moves(M), function (f) { }
+  };
+
+  std::vector<FunctionEHFrameInfo> EHFrames;
+
+  /// UsesLSDA - Indicates whether an FDE that uses the CIE at the given index
+  /// uses an LSDA. If so, then we need to encode that information in the CIE's
+  /// augmentation.
+  DenseMap<unsigned, bool> UsesLSDA;
+
+  /// shouldEmitTable - Per-function flag to indicate if EH tables should
+  /// be emitted.
+  bool shouldEmitTable;
+
+  /// shouldEmitMoves - Per-function flag to indicate if frame moves info
+  /// should be emitted.
+  bool shouldEmitMoves;
+
+  /// shouldEmitTableModule - Per-module flag to indicate if EH tables
+  /// should be emitted.
+  bool shouldEmitTableModule;
+
+  /// shouldEmitFrameModule - Per-module flag to indicate if frame moves
+  /// should be emitted.
+  bool shouldEmitMovesModule;
+
+  /// ExceptionTimer - Timer for the Dwarf exception writer.
+  Timer *ExceptionTimer;
+
+  /// SizeOfEncodedValue - Return the size of the encoding in bytes.
+  unsigned SizeOfEncodedValue(unsigned Encoding);
+
+  /// EmitCIE - Emit a Common Information Entry (CIE). This holds information
+  /// that is shared among many Frame Description Entries.  There is at least
+  /// one CIE in every non-empty .debug_frame section.
+  void EmitCIE(const Function *Personality, unsigned Index);
+
+  /// EmitFDE - Emit the Frame Description Entry (FDE) for the function.
+  void EmitFDE(const FunctionEHFrameInfo &EHFrameInfo);
+
+  /// EmitExceptionTable - Emit landing pads and actions.
+  ///
+  /// The general organization of the table is complex, but the basic concepts
+  /// are easy.  First there is a header which describes the location and
+  /// organization of the three components that follow.
+  ///  1. The landing pad site information describes the range of code covered
+  ///     by the try.  In our case it's an accumulation of the ranges covered
+  ///     by the invokes in the try.  There is also a reference to the landing
+  ///     pad that handles the exception once processed.  Finally an index into
+  ///     the actions table.
+  ///  2. The action table, in our case, is composed of pairs of type ids
+  ///     and next action offset.  Starting with the action index from the
+  ///     landing pad site, each type Id is checked for a match to the current
+  ///     exception.  If it matches then the exception and type id are passed
+  ///     on to the landing pad.  Otherwise the next action is looked up.  This
+  ///     chain is terminated with a next action of zero.  If no type id is
+  ///     found the frame is unwound and handling continues.
+  ///  3. Type id table contains references to all the C++ typeinfo for all
+  ///     catches in the function.  This tables is reversed indexed base 1.
+
+  /// SharedTypeIds - How many leading type ids two landing pads have in common.
+  static unsigned SharedTypeIds(const LandingPadInfo *L,
+                                const LandingPadInfo *R);
+
+  /// PadLT - Order landing pads lexicographically by type id.
+  static bool PadLT(const LandingPadInfo *L, const LandingPadInfo *R);
+
+  struct KeyInfo {
+    static inline unsigned getEmptyKey() { return -1U; }
+    static inline unsigned getTombstoneKey() { return -2U; }
+    static unsigned getHashValue(const unsigned &Key) { return Key; }
+    static bool isEqual(unsigned LHS, unsigned RHS) { return LHS == RHS; }
+  };
+
+  /// PadRange - Structure holding a try-range and the associated landing pad.
+  struct PadRange {
+    // The index of the landing pad.
+    unsigned PadIndex;
+    // The index of the begin and end labels in the landing pad's label lists.
+    unsigned RangeIndex;
+  };
+
+  typedef DenseMap<unsigned, PadRange, KeyInfo> RangeMapType;
+
+  /// ActionEntry - Structure describing an entry in the actions table.
+  struct ActionEntry {
+    int ValueForTypeID; // The value to write - may not be equal to the type id.
+    int NextAction;
+    struct ActionEntry *Previous;
+  };
+
+  /// CallSiteEntry - Structure describing an entry in the call-site table.
+  struct CallSiteEntry {
+    // The 'try-range' is BeginLabel .. EndLabel.
+    unsigned BeginLabel; // zero indicates the start of the function.
+    unsigned EndLabel;   // zero indicates the end of the function.
+
+    // The landing pad starts at PadLabel.
+    unsigned PadLabel;   // zero indicates that there is no landing pad.
+    unsigned Action;
+  };
+
+  /// ComputeActionsTable - Compute the actions table and gather the first
+  /// action index for each landing pad site.
+  unsigned ComputeActionsTable(const SmallVectorImpl<const LandingPadInfo*>&LPs,
+                               SmallVectorImpl<ActionEntry> &Actions,
+                               SmallVectorImpl<unsigned> &FirstActions);
+
+  /// CallToNoUnwindFunction - Return `true' if this is a call to a function
+  /// marked `nounwind'. Return `false' otherwise.
+  bool CallToNoUnwindFunction(const MachineInstr *MI);
+
+  /// ComputeCallSiteTable - Compute the call-site table.  The entry for an
+  /// invoke has a try-range containing the call, a non-zero landing pad and an
+  /// appropriate action.  The entry for an ordinary call has a try-range
+  /// containing the call and zero for the landing pad and the action.  Calls
+  /// marked 'nounwind' have no entry and must not be contained in the try-range
+  /// of any entry - they form gaps in the table.  Entries must be ordered by
+  /// try-range address.
+  void ComputeCallSiteTable(SmallVectorImpl<CallSiteEntry> &CallSites,
+                            const RangeMapType &PadMap,
+                            const SmallVectorImpl<const LandingPadInfo *> &LPs,
+                            const SmallVectorImpl<unsigned> &FirstActions);
+  void EmitExceptionTable();
+
+  /// CreateLabelDiff - Emit a label and subtract it from the expression we
+  /// already have.  This is equivalent to emitting "foo - .", but we have to
+  /// emit the label for "." directly.
+  const MCExpr *CreateLabelDiff(const MCExpr *ExprRef, const char *LabelName,
+                                unsigned Index);
+public:
+  //===--------------------------------------------------------------------===//
+  // Main entry points.
+  //
+  DwarfException(raw_ostream &OS, AsmPrinter *A, const MCAsmInfo *T);
+  virtual ~DwarfException();
+
+  /// BeginModule - Emit all exception information that should come prior to the
+  /// content.
+  void BeginModule(Module *m, MachineModuleInfo *mmi) {
+    this->M = m;
+    this->MMI = mmi;
+  }
+
+  /// EndModule - Emit all exception information that should come after the
+  /// content.
+  void EndModule();
+
+  /// BeginFunction - Gather pre-function exception information.  Assumes being
+  /// emitted immediately after the function entry point.
+  void BeginFunction(const MachineFunction *MF);
+
+  /// EndFunction - Gather and emit post-function exception information.
+  void EndFunction();
+};
+
+} // End of namespace llvm
+
+#endif
diff --git a/lib/CodeGen/AsmPrinter/DwarfLabel.cpp b/lib/CodeGen/AsmPrinter/DwarfLabel.cpp
new file mode 100644
index 0000000000..6e9293a03b
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/DwarfLabel.cpp
@@ -0,0 +1,32 @@
+//===--- lib/CodeGen/DwarfLabel.cpp - Dwarf Label -------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// DWARF Labels
+// 
+//===----------------------------------------------------------------------===//
+
+#include "DwarfLabel.h"
+#include "llvm/ADT/FoldingSet.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+/// Profile - Used to gather unique data for the folding set.
+///
+void DWLabel::Profile(FoldingSetNodeID &ID) const {
+  ID.AddString(Tag);
+  ID.AddInteger(Number);
+}
+
+#ifndef NDEBUG
+void DWLabel::print(raw_ostream &O) const {
+  O << "." << Tag;
+  if (Number) O << Number;
+}
+#endif
diff --git a/lib/CodeGen/AsmPrinter/DwarfLabel.h b/lib/CodeGen/AsmPrinter/DwarfLabel.h
new file mode 100644
index 0000000000..0c0cc4bdc3
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/DwarfLabel.h
@@ -0,0 +1,52 @@
+//===--- lib/CodeGen/DwarfLabel.h - Dwarf Label -----------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// DWARF Labels.
+// 
+//===----------------------------------------------------------------------===//
+
+#ifndef CODEGEN_ASMPRINTER_DWARFLABEL_H__
+#define CODEGEN_ASMPRINTER_DWARFLABEL_H__
+
+namespace llvm {
+  class FoldingSetNodeID;
+  class raw_ostream;
+
+  //===--------------------------------------------------------------------===//
+  /// DWLabel - Labels are used to track locations in the assembler file.
+  /// Labels appear in the form @verbatim <prefix><Tag><Number> @endverbatim,
+  /// where the tag is a category of label (Ex. location) and number is a value
+  /// unique in that category.
+  class DWLabel {
+    /// Tag - Label category tag. Should always be a statically declared C
+    /// string.
+    /// 
+    const char *Tag;
+
+    /// Number - Value to make label unique.
+    /// 
+    unsigned Number;
+  public:
+    DWLabel(const char *T, unsigned N) : Tag(T), Number(N) {}
+
+    // Accessors.
+    const char *getTag() const { return Tag; }
+    unsigned getNumber() const { return Number; }
+
+    /// Profile - Used to gather unique data for the folding set.
+    ///
+    void Profile(FoldingSetNodeID &ID) const;
+
+#ifndef NDEBUG
+    void print(raw_ostream &O) const;
+#endif
+  };
+} // end llvm namespace
+
+#endif
diff --git a/lib/CodeGen/AsmPrinter/DwarfPrinter.cpp b/lib/CodeGen/AsmPrinter/DwarfPrinter.cpp
new file mode 100644
index 0000000000..415390bc28
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/DwarfPrinter.cpp
@@ -0,0 +1,341 @@
+//===--- lib/CodeGen/DwarfPrinter.cpp - Dwarf Printer ---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Emit general DWARF directives.
+// 
+//===----------------------------------------------------------------------===//
+
+#include "DwarfPrinter.h"
+#include "llvm/Module.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetFrameInfo.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Support/Dwarf.h"
+#include "llvm/Support/ErrorHandling.h"
+using namespace llvm;
+
+DwarfPrinter::DwarfPrinter(raw_ostream &OS, AsmPrinter *A, const MCAsmInfo *T,
+                           const char *flavor)
+: O(OS), Asm(A), MAI(T), TD(Asm->TM.getTargetData()),
+  RI(Asm->TM.getRegisterInfo()), M(NULL), MF(NULL), MMI(NULL),
+  SubprogramCount(0), Flavor(flavor), SetCounter(1) {}
+
+void DwarfPrinter::PrintRelDirective(bool Force32Bit, bool isInSection) const {
+  if (isInSection && MAI->getDwarfSectionOffsetDirective())
+    O << MAI->getDwarfSectionOffsetDirective();
+  else if (Force32Bit || TD->getPointerSize() == sizeof(int32_t))
+    O << MAI->getData32bitsDirective();
+  else
+    O << MAI->getData64bitsDirective();
+}
+
+/// EOL - Print a newline character to asm stream.  If a comment is present
+/// then it will be printed first.  Comments should not contain '\n'.
+void DwarfPrinter::EOL(const Twine &Comment) const {
+  if (Asm->VerboseAsm && !Comment.isTriviallyEmpty()) {
+    Asm->O.PadToColumn(MAI->getCommentColumn());
+    Asm->O << Asm->MAI->getCommentString() << ' ' << Comment;
+  }
+  Asm->O << '\n';
+}
+
+static const char *DecodeDWARFEncoding(unsigned Encoding) {
+  switch (Encoding) {
+  case dwarf::DW_EH_PE_absptr: return "absptr";
+  case dwarf::DW_EH_PE_omit:   return "omit";
+  case dwarf::DW_EH_PE_pcrel:  return "pcrel";
+  case dwarf::DW_EH_PE_udata4: return "udata4";
+  case dwarf::DW_EH_PE_udata8: return "udata8";
+  case dwarf::DW_EH_PE_sdata4: return "sdata4";
+  case dwarf::DW_EH_PE_sdata8: return "sdata8";
+  case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata4: return "pcrel udata4";
+  case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata4: return "pcrel sdata4";
+  case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_udata8: return "pcrel udata8";
+  case dwarf::DW_EH_PE_pcrel | dwarf::DW_EH_PE_sdata8: return "pcrel sdata8";
+  case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |dwarf::DW_EH_PE_udata4:
+    return "indirect pcrel udata4";
+  case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |dwarf::DW_EH_PE_sdata4:
+    return "indirect pcrel sdata4";
+  case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |dwarf::DW_EH_PE_udata8:
+    return "indirect pcrel udata8";
+  case dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |dwarf::DW_EH_PE_sdata8:
+    return "indirect pcrel sdata8";
+  }
+  
+  return "<unknown encoding>";
+}
+
+/// EmitEncodingByte - Emit a .byte 42 directive that corresponds to an
+/// encoding.  If verbose assembly output is enabled, we output comments
+/// describing the encoding.  Desc is an optional string saying what the
+/// encoding is specifying (e.g. "LSDA").
+void DwarfPrinter::EmitEncodingByte(unsigned Val, const char *Desc) {
+  if (Asm->VerboseAsm) {
+    if (Desc != 0)
+      Asm->OutStreamer.AddComment(Twine(Desc)+" Encoding = " +
+                                  Twine(DecodeDWARFEncoding(Val)));
+    else
+      Asm->OutStreamer.AddComment(Twine("Encoding = ") +
+                                  DecodeDWARFEncoding(Val));
+  }
+
+  Asm->OutStreamer.EmitIntValue(Val, 1, 0/*addrspace*/);
+}
+
+/// EmitCFAByte - Emit a .byte 42 directive for a DW_CFA_xxx value.
+void DwarfPrinter::EmitCFAByte(unsigned Val) {
+  if (Asm->VerboseAsm) {
+    if (Val >= dwarf::DW_CFA_offset && Val < dwarf::DW_CFA_offset+64)
+      Asm->OutStreamer.AddComment("DW_CFA_offset + Reg (" + 
+                                  Twine(Val-dwarf::DW_CFA_offset) + ")");
+    else
+      Asm->OutStreamer.AddComment(dwarf::CallFrameString(Val));
+  }
+  Asm->OutStreamer.EmitIntValue(Val, 1, 0/*addrspace*/);
+}
+
+/// EmitSLEB128 - emit the specified signed leb128 value.
+void DwarfPrinter::EmitSLEB128(int Value, const char *Desc) const {
+  if (Asm->VerboseAsm && Desc)
+    Asm->OutStreamer.AddComment(Desc);
+    
+  if (MAI->hasLEB128()) {
+    O << "\t.sleb128\t" << Value;
+    Asm->OutStreamer.AddBlankLine();
+    return;
+  }
+
+  // If we don't have .sleb128, emit as .bytes.
+  int Sign = Value >> (8 * sizeof(Value) - 1);
+  bool IsMore;
+  
+  do {
+    unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
+    Value >>= 7;
+    IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0;
+    if (IsMore) Byte |= 0x80;
+    
+    Asm->OutStreamer.EmitIntValue(Byte, 1, /*addrspace*/0);
+  } while (IsMore);
+}
+
+/// EmitULEB128 - emit the specified signed leb128 value.
+void DwarfPrinter::EmitULEB128(unsigned Value, const char *Desc) const {
+  if (Asm->VerboseAsm && Desc)
+    Asm->OutStreamer.AddComment(Desc);
+ 
+  if (MAI->hasLEB128()) {
+    O << "\t.uleb128\t" << Value;
+    Asm->OutStreamer.AddBlankLine();
+    return;
+  }
+  
+  // If we don't have .uleb128, emit as .bytes.
+  do {
+    unsigned char Byte = static_cast<unsigned char>(Value & 0x7f);
+    Value >>= 7;
+    if (Value) Byte |= 0x80;
+    Asm->OutStreamer.EmitIntValue(Byte, 1, /*addrspace*/0);
+  } while (Value);
+}
+
+
+/// PrintLabelName - Print label name in form used by Dwarf writer.
+///
+void DwarfPrinter::PrintLabelName(const char *Tag, unsigned Number) const {
+  O << MAI->getPrivateGlobalPrefix() << Tag;
+  if (Number) O << Number;
+}
+void DwarfPrinter::PrintLabelName(const char *Tag, unsigned Number,
+                                  const char *Suffix) const {
+  O << MAI->getPrivateGlobalPrefix() << Tag;
+  if (Number) O << Number;
+  O << Suffix;
+}
+
+/// EmitLabel - Emit location label for internal use by Dwarf.
+///
+void DwarfPrinter::EmitLabel(const char *Tag, unsigned Number) const {
+  PrintLabelName(Tag, Number);
+  O << ":\n";
+}
+
+/// EmitReference - Emit a reference to a label.
+///
+void DwarfPrinter::EmitReference(const char *Tag, unsigned Number,
+                                 bool IsPCRelative, bool Force32Bit) const {
+  PrintRelDirective(Force32Bit);
+  PrintLabelName(Tag, Number);
+  if (IsPCRelative) O << "-" << MAI->getPCSymbol();
+}
+void DwarfPrinter::EmitReference(const std::string &Name, bool IsPCRelative,
+                                 bool Force32Bit) const {
+  PrintRelDirective(Force32Bit);
+  O << Name;
+  if (IsPCRelative) O << "-" << MAI->getPCSymbol();
+}
+
+void DwarfPrinter::EmitReference(const MCSymbol *Sym, bool IsPCRelative,
+                                 bool Force32Bit) const {
+  PrintRelDirective(Force32Bit);
+  O << *Sym;
+  if (IsPCRelative) O << "-" << MAI->getPCSymbol();
+}
+
+/// EmitDifference - Emit the difference between two labels.  If this assembler
+/// supports .set, we emit a .set of a temporary and then use it in the .word.
+void DwarfPrinter::EmitDifference(const char *TagHi, unsigned NumberHi,
+                                  const char *TagLo, unsigned NumberLo,
+                                  bool IsSmall) {
+  if (MAI->hasSetDirective()) {
+    // FIXME: switch to OutStreamer.EmitAssignment.
+    O << "\t.set\t";
+    PrintLabelName("set", SetCounter, Flavor);
+    O << ",";
+    PrintLabelName(TagHi, NumberHi);
+    O << "-";
+    PrintLabelName(TagLo, NumberLo);
+    O << "\n";
+
+    PrintRelDirective(IsSmall);
+    PrintLabelName("set", SetCounter, Flavor);
+    ++SetCounter;
+  } else {
+    PrintRelDirective(IsSmall);
+    PrintLabelName(TagHi, NumberHi);
+    O << "-";
+    PrintLabelName(TagLo, NumberLo);
+  }
+}
+
+void DwarfPrinter::EmitSectionOffset(const char* Label, const char* Section,
+                                     unsigned LabelNumber,
+                                     unsigned SectionNumber,
+                                     bool IsSmall, bool isEH,
+                                     bool useSet) {
+  bool printAbsolute = false;
+  if (isEH)
+    printAbsolute = MAI->isAbsoluteEHSectionOffsets();
+  else
+    printAbsolute = MAI->isAbsoluteDebugSectionOffsets();
+
+  if (MAI->hasSetDirective() && useSet) {
+    // FIXME: switch to OutStreamer.EmitAssignment.
+    O << "\t.set\t";
+    PrintLabelName("set", SetCounter, Flavor);
+    O << ",";
+    PrintLabelName(Label, LabelNumber);
+
+    if (!printAbsolute) {
+      O << "-";
+      PrintLabelName(Section, SectionNumber);
+    }
+
+    O << "\n";
+    PrintRelDirective(IsSmall);
+    PrintLabelName("set", SetCounter, Flavor);
+    ++SetCounter;
+    O << "\n";
+  } else {
+    PrintRelDirective(IsSmall, true);
+    PrintLabelName(Label, LabelNumber);
+
+    if (!printAbsolute) {
+      O << "-";
+      PrintLabelName(Section, SectionNumber);
+    }
+    O << "\n";
+  }
+}
+
+/// EmitFrameMoves - Emit frame instructions to describe the layout of the
+/// frame.
+void DwarfPrinter::EmitFrameMoves(const char *BaseLabel, unsigned BaseLabelID,
+                                  const std::vector<MachineMove> &Moves,
+                                  bool isEH) {
+  int stackGrowth =
+    Asm->TM.getFrameInfo()->getStackGrowthDirection() ==
+    TargetFrameInfo::StackGrowsUp ?
+    TD->getPointerSize() : -TD->getPointerSize();
+  bool IsLocal = BaseLabel && strcmp(BaseLabel, "label") == 0;
+
+  for (unsigned i = 0, N = Moves.size(); i < N; ++i) {
+    const MachineMove &Move = Moves[i];
+    unsigned LabelID = Move.getLabelID();
+
+    if (LabelID) {
+      LabelID = MMI->MappedLabel(LabelID);
+
+      // Throw out move if the label is invalid.
+      if (!LabelID) continue;
+    }
+
+    const MachineLocation &Dst = Move.getDestination();
+    const MachineLocation &Src = Move.getSource();
+
+    // Advance row if new location.
+    if (BaseLabel && LabelID && (BaseLabelID != LabelID || !IsLocal)) {
+      EmitCFAByte(dwarf::DW_CFA_advance_loc4);
+      EmitDifference("label", LabelID, BaseLabel, BaseLabelID, true);
+      Asm->O << '\n';
+
+      BaseLabelID = LabelID;
+      BaseLabel = "label";
+      IsLocal = true;
+    }
+
+    // If advancing cfa.
+    if (Dst.isReg() && Dst.getReg() == MachineLocation::VirtualFP) {
+      if (!Src.isReg()) {
+        if (Src.getReg() == MachineLocation::VirtualFP) {
+          EmitCFAByte(dwarf::DW_CFA_def_cfa_offset);
+        } else {
+          EmitCFAByte(dwarf::DW_CFA_def_cfa);
+          EmitULEB128(RI->getDwarfRegNum(Src.getReg(), isEH), "Register");
+        }
+
+        int Offset = -Src.getOffset();
+        EmitULEB128(Offset, "Offset");
+      } else {
+        llvm_unreachable("Machine move not supported yet.");
+      }
+    } else if (Src.isReg() &&
+               Src.getReg() == MachineLocation::VirtualFP) {
+      if (Dst.isReg()) {
+        EmitCFAByte(dwarf::DW_CFA_def_cfa_register);
+        EmitULEB128(RI->getDwarfRegNum(Dst.getReg(), isEH), "Register");
+      } else {
+        llvm_unreachable("Machine move not supported yet.");
+      }
+    } else {
+      unsigned Reg = RI->getDwarfRegNum(Src.getReg(), isEH);
+      int Offset = Dst.getOffset() / stackGrowth;
+
+      if (Offset < 0) {
+        EmitCFAByte(dwarf::DW_CFA_offset_extended_sf);
+        EmitULEB128(Reg, "Reg");
+        EmitSLEB128(Offset, "Offset");
+      } else if (Reg < 64) {
+        EmitCFAByte(dwarf::DW_CFA_offset + Reg);
+        EmitULEB128(Offset, "Offset");
+      } else {
+        EmitCFAByte(dwarf::DW_CFA_offset_extended);
+        EmitULEB128(Reg, "Reg");
+        EmitULEB128(Offset, "Offset");
+      }
+    }
+  }
+}
diff --git a/lib/CodeGen/AsmPrinter/DwarfPrinter.h b/lib/CodeGen/AsmPrinter/DwarfPrinter.h
new file mode 100644
index 0000000000..69d9c27ff0
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/DwarfPrinter.h
@@ -0,0 +1,167 @@
+//===--- lib/CodeGen/DwarfPrinter.h - Dwarf Printer -------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Emit general DWARF directives.
+// 
+//===----------------------------------------------------------------------===//
+
+#ifndef CODEGEN_ASMPRINTER_DWARFPRINTER_H__
+#define CODEGEN_ASMPRINTER_DWARFPRINTER_H__
+
+#include "DwarfLabel.h"
+#include "llvm/CodeGen/MachineLocation.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/FormattedStream.h"
+#include <vector>
+
+namespace llvm {
+class AsmPrinter;
+class MachineFunction;
+class MachineModuleInfo;
+class Module;
+class MCAsmInfo;
+class TargetData;
+class TargetRegisterInfo;
+class MCSymbol;
+class Twine;
+
+class DwarfPrinter {
+protected:
+  ~DwarfPrinter() {}
+
+  //===-------------------------------------------------------------==---===//
+  // Core attributes used by the DWARF printer.
+  //
+
+  /// O - Stream to .s file.
+  raw_ostream &O;
+
+  /// Asm - Target of Dwarf emission.
+  AsmPrinter *Asm;
+
+  /// MAI - Target asm information.
+  const MCAsmInfo *MAI;
+
+  /// TD - Target data.
+  const TargetData *TD;
+
+  /// RI - Register Information.
+  const TargetRegisterInfo *RI;
+
+  /// M - Current module.
+  Module *M;
+
+  /// MF - Current machine function.
+  const MachineFunction *MF;
+
+  /// MMI - Collected machine module information.
+  MachineModuleInfo *MMI;
+
+  /// SubprogramCount - The running count of functions being compiled.
+  unsigned SubprogramCount;
+
+  /// Flavor - A unique string indicating what dwarf producer this is, used to
+  /// unique labels.
+  const char * const Flavor;
+
+  /// SetCounter - A unique number for each '.set' directive.
+  unsigned SetCounter;
+
+  DwarfPrinter(raw_ostream &OS, AsmPrinter *A, const MCAsmInfo *T,
+               const char *flavor);
+public:
+  
+  //===------------------------------------------------------------------===//
+  // Accessors.
+  //
+  const AsmPrinter *getAsm() const { return Asm; }
+  MachineModuleInfo *getMMI() const { return MMI; }
+  const MCAsmInfo *getMCAsmInfo() const { return MAI; }
+  const TargetData *getTargetData() const { return TD; }
+
+  void PrintRelDirective(bool Force32Bit = false,
+                         bool isInSection = false) const;
+
+  /// EOL - Print a newline character to asm stream.  If a comment is present
+  /// then it will be printed first.  Comments should not contain '\n'.
+  void EOL(const Twine &Comment) const;
+  
+  /// EmitEncodingByte - Emit a .byte 42 directive that corresponds to an
+  /// encoding.  If verbose assembly output is enabled, we output comments
+  /// describing the encoding.  Desc is a string saying what the encoding is
+  /// specifying (e.g. "LSDA").
+  void EmitEncodingByte(unsigned Val, const char *Desc);
+  
+  /// EmitCFAByte - Emit a .byte 42 directive for a DW_CFA_xxx value.
+  void EmitCFAByte(unsigned Val);
+  
+  
+  /// EmitSLEB128 - emit the specified signed leb128 value.
+  void EmitSLEB128(int Value, const char *Desc) const;
+
+  /// EmitULEB128 - emit the specified unsigned leb128 value.
+  void EmitULEB128(unsigned Value, const char *Desc = 0) const;
+
+  
+  /// PrintLabelName - Print label name in form used by Dwarf writer.
+  ///
+  void PrintLabelName(const DWLabel &Label) const {
+    PrintLabelName(Label.getTag(), Label.getNumber());
+  }
+  void PrintLabelName(const char *Tag, unsigned Number) const;
+  void PrintLabelName(const char *Tag, unsigned Number,
+                      const char *Suffix) const;
+
+  /// EmitLabel - Emit location label for internal use by Dwarf.
+  ///
+  void EmitLabel(const DWLabel &Label) const {
+    EmitLabel(Label.getTag(), Label.getNumber());
+  }
+  void EmitLabel(const char *Tag, unsigned Number) const;
+
+  /// EmitReference - Emit a reference to a label.
+  ///
+  void EmitReference(const DWLabel &Label, bool IsPCRelative = false,
+                     bool Force32Bit = false) const {
+    EmitReference(Label.getTag(), Label.getNumber(),
+                  IsPCRelative, Force32Bit);
+  }
+  void EmitReference(const char *Tag, unsigned Number,
+                     bool IsPCRelative = false,
+                     bool Force32Bit = false) const;
+  void EmitReference(const std::string &Name, bool IsPCRelative = false,
+                     bool Force32Bit = false) const;
+  void EmitReference(const MCSymbol *Sym, bool IsPCRelative = false,
+                     bool Force32Bit = false) const;
+
+  /// EmitDifference - Emit the difference between two labels.
+  void EmitDifference(const DWLabel &LabelHi, const DWLabel &LabelLo,
+                      bool IsSmall = false) {
+    EmitDifference(LabelHi.getTag(), LabelHi.getNumber(),
+                   LabelLo.getTag(), LabelLo.getNumber(),
+                   IsSmall);
+  }
+  void EmitDifference(const char *TagHi, unsigned NumberHi,
+                      const char *TagLo, unsigned NumberLo,
+                      bool IsSmall = false);
+
+  void EmitSectionOffset(const char* Label, const char* Section,
+                         unsigned LabelNumber, unsigned SectionNumber,
+                         bool IsSmall = false, bool isEH = false,
+                         bool useSet = true);
+
+  /// EmitFrameMoves - Emit frame instructions to describe the layout of the
+  /// frame.
+  void EmitFrameMoves(const char *BaseLabel, unsigned BaseLabelID,
+                      const std::vector<MachineMove> &Moves, bool isEH);
+};
+
+} // end llvm namespace
+
+#endif
diff --git a/lib/CodeGen/AsmPrinter/DwarfWriter.cpp b/lib/CodeGen/AsmPrinter/DwarfWriter.cpp
new file mode 100644
index 0000000000..08e1bbce08
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/DwarfWriter.cpp
@@ -0,0 +1,100 @@
+//===-- llvm/CodeGen/DwarfWriter.cpp - Dwarf Framework --------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for writing dwarf info into asm files.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/DwarfWriter.h"
+#include "DwarfDebug.h"
+#include "DwarfException.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+
+using namespace llvm;
+
+static RegisterPass<DwarfWriter>
+X("dwarfwriter", "DWARF Information Writer");
+char DwarfWriter::ID = 0;
+
+//===----------------------------------------------------------------------===//
+/// DwarfWriter Implementation
+///
+
+DwarfWriter::DwarfWriter()
+  : ImmutablePass(&ID), DD(0), DE(0) {}
+
+DwarfWriter::~DwarfWriter() {
+  delete DE;
+  delete DD;
+}
+
+/// BeginModule - Emit all Dwarf sections that should come prior to the
+/// content.
+void DwarfWriter::BeginModule(Module *M,
+                              MachineModuleInfo *MMI,
+                              raw_ostream &OS, AsmPrinter *A,
+                              const MCAsmInfo *T) {
+  DE = new DwarfException(OS, A, T);
+  DD = new DwarfDebug(OS, A, T);
+  DE->BeginModule(M, MMI);
+  DD->beginModule(M, MMI);
+}
+
+/// EndModule - Emit all Dwarf sections that should come after the content.
+///
+void DwarfWriter::EndModule() {
+  DE->EndModule();
+  DD->endModule();
+  delete DD; DD = 0;
+  delete DE; DE = 0;
+}
+
+/// BeginFunction - Gather pre-function debug information.  Assumes being
+/// emitted immediately after the function entry point.
+void DwarfWriter::BeginFunction(const MachineFunction *MF) {
+  DE->BeginFunction(MF);
+  DD->beginFunction(MF);
+}
+
+/// EndFunction - Gather and emit post-function debug information.
+///
+void DwarfWriter::EndFunction(const MachineFunction *MF) {
+  DD->endFunction(MF);
+  DE->EndFunction();
+
+  if (MachineModuleInfo *MMI = DD->getMMI() ? DD->getMMI() : DE->getMMI())
+    // Clear function debug information.
+    MMI->EndFunction();
+}
+
+/// RecordSourceLine - Records location information and associates it with a 
+/// label. Returns a unique label ID used to generate a label and provide
+/// correspondence to the source line list.
+unsigned DwarfWriter::RecordSourceLine(unsigned Line, unsigned Col, 
+                                       MDNode *Scope) {
+  return DD->recordSourceLine(Line, Col, Scope);
+}
+
+/// getRecordSourceLineCount - Count source lines.
+unsigned DwarfWriter::getRecordSourceLineCount() {
+  return DD->getSourceLineCount();
+}
+
+/// ShouldEmitDwarfDebug - Returns true if Dwarf debugging declarations should
+/// be emitted.
+bool DwarfWriter::ShouldEmitDwarfDebug() const {
+  return DD && DD->ShouldEmitDwarfDebug();
+}
+
+void DwarfWriter::BeginScope(const MachineInstr *MI, unsigned L) {
+  DD->beginScope(MI, L);
+}
+void DwarfWriter::EndScope(const MachineInstr *MI) {
+  DD->endScope(MI);
+}
diff --git a/lib/CodeGen/AsmPrinter/Makefile b/lib/CodeGen/AsmPrinter/Makefile
new file mode 100644
index 0000000000..60aa6cbcf6
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/Makefile
@@ -0,0 +1,13 @@
+##===- lib/CodeGen/AsmPrinter/Makefile ---------------------*- Makefile -*-===##
+#
+#                     The LLVM Compiler Infrastructure
+#
+# This file is distributed under the University of Illinois Open Source
+# License. See LICENSE.TXT for details.
+#
+##===----------------------------------------------------------------------===##
+
+LEVEL = ../../..
+LIBRARYNAME = LLVMAsmPrinter
+
+include $(LEVEL)/Makefile.common
diff --git a/lib/CodeGen/AsmPrinter/OcamlGCPrinter.cpp b/lib/CodeGen/AsmPrinter/OcamlGCPrinter.cpp
new file mode 100644
index 0000000000..3531ed6039
--- /dev/null
+++ b/lib/CodeGen/AsmPrinter/OcamlGCPrinter.cpp
@@ -0,0 +1,160 @@
+//===-- OcamlGCPrinter.cpp - Ocaml frametable emitter ---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements printing the assembly code for an Ocaml frametable.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/GCs.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/CodeGen/GCMetadataPrinter.h"
+#include "llvm/Module.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetLoweringObjectFile.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/FormattedStream.h"
+using namespace llvm;
+
+namespace {
+
+  class OcamlGCMetadataPrinter : public GCMetadataPrinter {
+  public:
+    void beginAssembly(raw_ostream &OS, AsmPrinter &AP,
+                       const MCAsmInfo &MAI);
+
+    void finishAssembly(raw_ostream &OS, AsmPrinter &AP,
+                        const MCAsmInfo &MAI);
+  };
+
+}
+
+static GCMetadataPrinterRegistry::Add<OcamlGCMetadataPrinter>
+Y("ocaml", "ocaml 3.10-compatible collector");
+
+void llvm::linkOcamlGCPrinter() { }
+
+static void EmitCamlGlobal(const Module &M, raw_ostream &OS, AsmPrinter &AP,
+                           const MCAsmInfo &MAI, const char *Id) {
+  const std::string &MId = M.getModuleIdentifier();
+
+  std::string Mangled;
+  Mangled += MAI.getGlobalPrefix();
+  Mangled += "caml";
+  size_t Letter = Mangled.size();
+  Mangled.append(MId.begin(), std::find(MId.begin(), MId.end(), '.'));
+  Mangled += "__";
+  Mangled += Id;
+
+  // Capitalize the first letter of the module name.
+  Mangled[Letter] = toupper(Mangled[Letter]);
+
+  if (const char *GlobalDirective = MAI.getGlobalDirective())
+    OS << GlobalDirective << Mangled << "\n";
+  OS << Mangled << ":\n";
+}
+
+void OcamlGCMetadataPrinter::beginAssembly(raw_ostream &OS, AsmPrinter &AP,
+                                           const MCAsmInfo &MAI) {
+  AP.OutStreamer.SwitchSection(AP.getObjFileLowering().getTextSection());
+  EmitCamlGlobal(getModule(), OS, AP, MAI, "code_begin");
+
+  AP.OutStreamer.SwitchSection(AP.getObjFileLowering().getDataSection());
+  EmitCamlGlobal(getModule(), OS, AP, MAI, "data_begin");
+}
+
+/// emitAssembly - Print the frametable. The ocaml frametable format is thus:
+///
+///   extern "C" struct align(sizeof(intptr_t)) {
+///     uint16_t NumDescriptors;
+///     struct align(sizeof(intptr_t)) {
+///       void *ReturnAddress;
+///       uint16_t FrameSize;
+///       uint16_t NumLiveOffsets;
+///       uint16_t LiveOffsets[NumLiveOffsets];
+///     } Descriptors[NumDescriptors];
+///   } caml${module}__frametable;
+///
+/// Note that this precludes programs from stack frames larger than 64K
+/// (FrameSize and LiveOffsets would overflow). FrameTablePrinter will abort if
+/// either condition is detected in a function which uses the GC.
+///
+void OcamlGCMetadataPrinter::finishAssembly(raw_ostream &OS, AsmPrinter &AP,
+                                            const MCAsmInfo &MAI) {
+  const char *AddressDirective;
+  int AddressAlignLog;
+  if (AP.TM.getTargetData()->getPointerSize() == sizeof(int32_t)) {
+    AddressDirective = MAI.getData32bitsDirective();
+    AddressAlignLog = 2;
+  } else {
+    AddressDirective = MAI.getData64bitsDirective();
+    AddressAlignLog = 3;
+  }
+
+  AP.OutStreamer.SwitchSection(AP.getObjFileLowering().getTextSection());
+  EmitCamlGlobal(getModule(), OS, AP, MAI, "code_end");
+
+  AP.OutStreamer.SwitchSection(AP.getObjFileLowering().getDataSection());
+  EmitCamlGlobal(getModule(), OS, AP, MAI, "data_end");
+
+  OS << AddressDirective << 0 << '\n'; // FIXME: Why does ocaml emit this??
+
+  AP.OutStreamer.SwitchSection(AP.getObjFileLowering().getDataSection());
+  EmitCamlGlobal(getModule(), OS, AP, MAI, "frametable");
+
+  for (iterator I = begin(), IE = end(); I != IE; ++I) {
+    GCFunctionInfo &FI = **I;
+
+    uint64_t FrameSize = FI.getFrameSize();
+    if (FrameSize >= 1<<16) {
+      std::string msg;
+      raw_string_ostream Msg(msg);
+      Msg << "Function '" << FI.getFunction().getName()
+           << "' is too large for the ocaml GC! "
+           << "Frame size " << FrameSize << " >= 65536.\n";
+      Msg << "(" << uintptr_t(&FI) << ")";
+      llvm_report_error(Msg.str()); // Very rude!
+    }
+
+    OS << "\t" << MAI.getCommentString() << " live roots for "
+       << FI.getFunction().getName() << "\n";
+
+    for (GCFunctionInfo::iterator J = FI.begin(), JE = FI.end(); J != JE; ++J) {
+      size_t LiveCount = FI.live_size(J);
+      if (LiveCount >= 1<<16) {
+        std::string msg;
+        raw_string_ostream Msg(msg);
+        Msg << "Function '" << FI.getFunction().getName()
+             << "' is too large for the ocaml GC! "
+             << "Live root count " << LiveCount << " >= 65536.";
+        llvm_report_error(Msg.str()); // Very rude!
+      }
+
+      OS << AddressDirective
+        << MAI.getPrivateGlobalPrefix() << "label" << J->Num << '\n';
+
+      AP.EmitInt16(FrameSize);
+
+      AP.EmitInt16(LiveCount);
+
+      for (GCFunctionInfo::live_iterator K = FI.live_begin(J),
+                                         KE = FI.live_end(J); K != KE; ++K) {
+        assert(K->StackOffset < 1<<16 &&
+               "GC root stack offset is outside of fixed stack frame and out "
+               "of range for ocaml GC!");
+
+        AP.EmitInt32(K->StackOffset);
+      }
+
+      AP.EmitAlignment(AddressAlignLog);
+    }
+  }
+}