Add a MachO-specific "mode" to llvm-objdump, that, if enabled, gathers additional information that are only available on MachO.

- It can take FunctionStarts from a binary to find entry points more accurately.
- Symbol offsets in executables are correct now.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140028 91177308-0d34-0410-b5e6-96231b3b80d8

6 files changed, 671 insertions, 205 deletions

diff --git a/tools/llvm-objdump/CMakeLists.txt b/tools/llvm-objdump/CMakeLists.txt
index 4c7ab20..db78864 100644
--- a/tools/llvm-objdump/CMakeLists.txt
+++ b/tools/llvm-objdump/CMakeLists.txt
@@ -8,5 +8,6 @@ set(LLVM_LINK_COMPONENTS
 
 add_llvm_tool(llvm-objdump
   llvm-objdump.cpp
+  MachODump.cpp
   MCFunction.cpp
   )
diff --git a/tools/llvm-objdump/MCFunction.cpp b/tools/llvm-objdump/MCFunction.cpp
index 5f16496..03390c2 100644
--- a/tools/llvm-objdump/MCFunction.cpp
+++ b/tools/llvm-objdump/MCFunction.cpp
@@ -30,48 +30,77 @@ MCFunction
 MCFunction::createFunctionFromMC(StringRef Name, const MCDisassembler *DisAsm,
                                  const MemoryObject &Region, uint64_t Start,
                                  uint64_t End, const MCInstrAnalysis *Ana,
-                                 raw_ostream &DebugOut) {
+                                 raw_ostream &DebugOut,
+                                 SmallVectorImpl<uint64_t> &Calls) {
+  std::vector<MCDecodedInst> Instructions;
   std::set<uint64_t> Splits;
   Splits.insert(Start);
-  std::vector<MCDecodedInst> Instructions;
   uint64_t Size;
 
+  MCFunction f(Name);
+
+  {
+  DenseSet<uint64_t> VisitedInsts;
+  SmallVector<uint64_t, 16> WorkList;
+  WorkList.push_back(Start);
   // Disassemble code and gather basic block split points.
-  for (uint64_t Index = Start; Index < End; Index += Size) {
-    MCInst Inst;
+  while (!WorkList.empty()) {
+    uint64_t Index = WorkList.pop_back_val();
+    if (VisitedInsts.find(Index) != VisitedInsts.end())
+      continue;
 
-    if (DisAsm->getInstruction(Inst, Size, Region, Index, DebugOut, nulls())) {
-      if (Ana->isBranch(Inst)) {
-        uint64_t targ = Ana->evaluateBranch(Inst, Index, Size);
-        // FIXME: Distinguish relocations from nop jumps.
-        if (targ != -1ULL && (targ == Index+Size || targ >= End)) {
+    for (;Index < End; Index += Size) {
+      MCInst Inst;
+
+      if (DisAsm->getInstruction(Inst, Size, Region, Index, DebugOut, nulls())){
+        if (Ana->isBranch(Inst)) {
+          uint64_t targ = Ana->evaluateBranch(Inst, Index, Size);
+          if (targ != -1ULL && targ == Index+Size) {
+            Instructions.push_back(MCDecodedInst(Index, Size, Inst));
+            VisitedInsts.insert(Index);
+            continue;
+          }
+          if (targ != -1ULL) {
+            Splits.insert(targ);
+            WorkList.push_back(targ);
+            WorkList.push_back(Index+Size);
+          }
+          Splits.insert(Index+Size);
+          Instructions.push_back(MCDecodedInst(Index, Size, Inst));
+          VisitedInsts.insert(Index);
+          break;
+        } else if (Ana->isReturn(Inst)) {
+          Splits.insert(Index+Size);
           Instructions.push_back(MCDecodedInst(Index, Size, Inst));
-          continue; // Skip branches that leave the function.
+          VisitedInsts.insert(Index);
+          break;
+        } else if (Ana->isCall(Inst)) {
+          uint64_t targ = Ana->evaluateBranch(Inst, Index, Size);
+          if (targ != -1ULL && targ != Index+Size) {
+            Calls.push_back(targ);
+          }
         }
-        if (targ != -1ULL)
-          Splits.insert(targ);
-        Splits.insert(Index+Size);
-      } else if (Ana->isReturn(Inst)) {
-        Splits.insert(Index+Size);
-      }
 
-      Instructions.push_back(MCDecodedInst(Index, Size, Inst));
-    } else {
-      errs() << "warning: invalid instruction encoding\n";
-      if (Size == 0)
-        Size = 1; // skip illegible bytes
+        Instructions.push_back(MCDecodedInst(Index, Size, Inst));
+        VisitedInsts.insert(Index);
+      } else {
+        VisitedInsts.insert(Index);
+        errs().write_hex(Index) << ": warning: invalid instruction encoding\n";
+        if (Size == 0)
+          Size = 1; // skip illegible bytes
+      }
     }
-
+  }
   }
 
-  MCFunction f(Name);
+  std::sort(Instructions.begin(), Instructions.end());
 
-  // Create basic blocks.
+   // Create basic blocks.
   unsigned ii = 0, ie = Instructions.size();
   for (std::set<uint64_t>::iterator spi = Splits.begin(),
-       spe = Splits.end(); spi != spe; ++spi) {
+       spe = llvm::prior(Splits.end()); spi != spe; ++spi) {
     MCBasicBlock BB;
-    uint64_t BlockEnd = llvm::next(spi) == spe ? End : *llvm::next(spi);
+    uint64_t BlockEnd = *llvm::next(spi);
     // Add instructions to the BB.
     for (; ii != ie; ++ii) {
       if (Instructions[ii].Address < *spi ||
@@ -82,6 +111,8 @@ MCFunction::createFunctionFromMC(StringRef Name, const MCDisassembler *DisAsm,
     f.addBlock(*spi, BB);
   }
 
+  std::sort(f.Blocks.begin(), f.Blocks.end());
+
   // Calculate successors of each block.
   for (MCFunction::iterator i = f.begin(), e = f.end(); i != e; ++i) {
     MCBasicBlock &BB = i->second;
@@ -94,16 +125,16 @@ MCFunction::createFunctionFromMC(StringRef Name, const MCDisassembler *DisAsm,
         // Indirect branch. Bail and add all blocks of the function as a
         // successor.
         for (MCFunction::iterator i = f.begin(), e = f.end(); i != e; ++i)
-          BB.addSucc(&i->second);
+          BB.addSucc(i->first);
       } else if (targ != Inst.Address+Inst.Size)
-        BB.addSucc(&f.getBlockAtAddress(targ));
+        BB.addSucc(targ);
       // Conditional branches can also fall through to the next block.
       if (Ana->isConditionalBranch(Inst.Inst) && llvm::next(i) != e)
-        BB.addSucc(&llvm::next(i)->second);
+        BB.addSucc(llvm::next(i)->first);
     } else {
       // No branch. Fall through to the next block.
       if (!Ana->isReturn(Inst.Inst) && llvm::next(i) != e)
-        BB.addSucc(&llvm::next(i)->second);
+        BB.addSucc(llvm::next(i)->first);
     }
   }
 
diff --git a/tools/llvm-objdump/MCFunction.h b/tools/llvm-objdump/MCFunction.h
index 023ca39..4677d91 100644
--- a/tools/llvm-objdump/MCFunction.h
+++ b/tools/llvm-objdump/MCFunction.h
@@ -12,8 +12,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+#ifndef LLVM_OBJECTDUMP_MCFUNCTION_H
+#define LLVM_OBJECTDUMP_MCFUNCTION_H
+
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/DenseSet.h"
 #include "llvm/MC/MCInst.h"
 #include <map>
 
@@ -31,15 +34,20 @@ struct MCDecodedInst {
   uint64_t Size;
   MCInst Inst;
 
+  MCDecodedInst() {}
   MCDecodedInst(uint64_t Address, uint64_t Size, MCInst Inst)
     : Address(Address), Size(Size), Inst(Inst) {}
+
+  bool operator<(const MCDecodedInst &RHS) const {
+    return Address < RHS.Address;
+  }
 };
 
 /// MCBasicBlock - Consists of multiple MCDecodedInsts and a list of successing
 /// MCBasicBlocks.
 class MCBasicBlock {
-  SmallVector<MCDecodedInst, 8> Insts;
-  typedef SmallPtrSet<MCBasicBlock*, 8> SetTy;
+  std::vector<MCDecodedInst> Insts;
+  typedef DenseSet<uint64_t> SetTy;
   SetTy Succs;
 public:
   ArrayRef<MCDecodedInst> getInsts() const { return Insts; }
@@ -48,10 +56,14 @@ public:
   succ_iterator succ_begin() const { return Succs.begin(); }
   succ_iterator succ_end() const { return Succs.end(); }
 
-  bool contains(MCBasicBlock *BB) const { return Succs.count(BB); }
+  bool contains(uint64_t Addr) const { return Succs.count(Addr); }
 
   void addInst(const MCDecodedInst &Inst) { Insts.push_back(Inst); }
-  void addSucc(MCBasicBlock *BB) { Succs.insert(BB); }
+  void addSucc(uint64_t Addr) { Succs.insert(Addr); }
+
+  bool operator<(const MCBasicBlock &RHS) const {
+    return Insts.size() < RHS.Insts.size();
+  }
 };
 
 /// MCFunction - Represents a named function in machine code, containing
@@ -59,7 +71,7 @@ public:
 class MCFunction {
   const StringRef Name;
   // Keep BBs sorted by address.
-  typedef std::map<uint64_t, MCBasicBlock> MapTy;
+  typedef std::vector<std::pair<uint64_t, MCBasicBlock> > MapTy;
   MapTy Blocks;
 public:
   MCFunction(StringRef Name) : Name(Name) {}
@@ -68,7 +80,8 @@ public:
   static MCFunction
   createFunctionFromMC(StringRef Name, const MCDisassembler *DisAsm,
                        const MemoryObject &Region, uint64_t Start, uint64_t End,
-                       const MCInstrAnalysis *Ana, raw_ostream &DebugOut);
+                       const MCInstrAnalysis *Ana, raw_ostream &DebugOut,
+                       SmallVectorImpl<uint64_t> &Calls);
 
   typedef MapTy::iterator iterator;
   iterator begin() { return Blocks.begin(); }
@@ -77,14 +90,11 @@ public:
   StringRef getName() const { return Name; }
 
   MCBasicBlock &addBlock(uint64_t Address, const MCBasicBlock &BB) {
-    assert(!Blocks.count(Address) && "Already a BB at address.");
-    return Blocks[Address] = BB;
-  }
-
-  MCBasicBlock &getBlockAtAddress(uint64_t Address) {
-    assert(Blocks.count(Address) && "No BB at address.");
-    return Blocks[Address];
+    Blocks.push_back(std::make_pair(Address, BB));
+    return Blocks.back().second;
   }
 };
 
 }
+
+#endif
diff --git a/tools/llvm-objdump/MachODump.cpp b/tools/llvm-objdump/MachODump.cpp
new file mode 100644
index 0000000..49687d1
--- /dev/null
+++ b/tools/llvm-objdump/MachODump.cpp
@@ -0,0 +1,489 @@
+//===-- MachODump.cpp - Object file dumping utility for llvm --------------===//
+//
+//                     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 MachO-specific dumper for llvm-objdump.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm-objdump.h"
+#include "MCFunction.h"
+#include "llvm/Support/MachO.h"
+#include "llvm/Object/MachOObject.h"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCDisassembler.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCInstPrinter.h"
+#include "llvm/MC/MCInstrAnalysis.h"
+#include "llvm/MC/MCInstrDesc.h"
+#include "llvm/MC/MCInstrInfo.h"
+#include "llvm/MC/MCSubtargetInfo.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/GraphWriter.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Support/TargetSelect.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/system_error.h"
+#include <algorithm>
+#include <cstring>
+using namespace llvm;
+using namespace object;
+
+static cl::opt<bool>
+  CFG("cfg", cl::desc("Create a CFG for every symbol in the object file and"
+                      "write it to a graphviz file (MachO-only)"));
+
+static const Target *GetTarget(const MachOObject *MachOObj) {
+  // Figure out the target triple.
+  llvm::Triple TT("unknown-unknown-unknown");
+  switch (MachOObj->getHeader().CPUType) {
+  case llvm::MachO::CPUTypeI386:
+    TT.setArch(Triple::ArchType(Triple::x86));
+    break;
+  case llvm::MachO::CPUTypeX86_64:
+    TT.setArch(Triple::ArchType(Triple::x86_64));
+    break;
+  case llvm::MachO::CPUTypeARM:
+    TT.setArch(Triple::ArchType(Triple::arm));
+    break;
+  case llvm::MachO::CPUTypePowerPC:
+    TT.setArch(Triple::ArchType(Triple::ppc));
+    break;
+  case llvm::MachO::CPUTypePowerPC64:
+    TT.setArch(Triple::ArchType(Triple::ppc64));
+    break;
+  }
+
+  TripleName = TT.str();
+
+  // Get the target specific parser.
+  std::string Error;
+  const Target *TheTarget = TargetRegistry::lookupTarget(TripleName, Error);
+  if (TheTarget)
+    return TheTarget;
+
+  errs() << "llvm-objdump: error: unable to get target for '" << TripleName
+         << "', see --version and --triple.\n";
+  return 0;
+}
+
+struct Section {
+  char Name[16];
+  uint64_t Address;
+  uint64_t Size;
+  uint32_t Offset;
+  uint32_t NumRelocs;
+  uint64_t RelocTableOffset;
+};
+
+struct Symbol {
+  uint64_t Value;
+  uint32_t StringIndex;
+  uint8_t SectionIndex;
+  bool operator<(const Symbol &RHS) const { return Value < RHS.Value; }
+};
+
+static void DumpAddress(uint64_t Address, ArrayRef<Section> Sections,
+                        MachOObject *MachOObj, raw_ostream &OS) {
+  for (unsigned i = 0; i != Sections.size(); ++i) {
+    uint64_t addr = Address-Sections[i].Address;
+    if (Sections[i].Address <= Address &&
+        Sections[i].Address + Sections[i].Size > Address) {
+      StringRef bytes = MachOObj->getData(Sections[i].Offset,
+                                          Sections[i].Size);
+      if (!strcmp(Sections[i].Name, "__cstring"))
+        OS << '"' << bytes.substr(addr, bytes.find('\0', addr)) << '"';
+      if (!strcmp(Sections[i].Name, "__cfstring"))
+        OS << "@\"" << bytes.substr(addr, bytes.find('\0', addr)) << '"';
+    }
+  }
+}
+
+void llvm::DisassembleInputMachO(StringRef Filename) {
+  OwningPtr<MemoryBuffer> Buff;
+
+  if (error_code ec = MemoryBuffer::getFileOrSTDIN(Filename, Buff)) {
+    errs() << "llvm-objdump: " << Filename << ": " << ec.message() << "\n";
+    return;
+  }
+
+  OwningPtr<MachOObject> MachOObj(MachOObject::LoadFromBuffer(Buff.take()));
+
+  const Target *TheTarget = GetTarget(MachOObj.get());
+  if (!TheTarget) {
+    // GetTarget prints out stuff.
+    return;
+  }
+  const MCInstrInfo *InstrInfo = TheTarget->createMCInstrInfo();
+  OwningPtr<MCInstrAnalysis>
+    InstrAnalysis(TheTarget->createMCInstrAnalysis(InstrInfo));
+
+  // Set up disassembler.
+  OwningPtr<const MCAsmInfo> AsmInfo(TheTarget->createMCAsmInfo(TripleName));
+
+  if (!AsmInfo) {
+    errs() << "error: no assembly info for target " << TripleName << "\n";
+    return;
+  }
+
+  OwningPtr<const MCSubtargetInfo>
+    STI(TheTarget->createMCSubtargetInfo(TripleName, "", ""));
+
+  if (!STI) {
+    errs() << "error: no subtarget info for target " << TripleName << "\n";
+    return;
+  }
+
+  OwningPtr<const MCDisassembler> DisAsm(TheTarget->createMCDisassembler(*STI));
+  if (!DisAsm) {
+    errs() << "error: no disassembler for target " << TripleName << "\n";
+    return;
+  }
+
+  int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
+  OwningPtr<MCInstPrinter> IP(TheTarget->createMCInstPrinter(
+        AsmPrinterVariant, *AsmInfo, *STI));
+  if (!IP) {
+    errs() << "error: no instruction printer for target " << TripleName << '\n';
+    return;
+  }
+
+  outs() << '\n';
+  outs() << Filename << ":\n\n";
+
+  const macho::Header &Header = MachOObj->getHeader();
+
+  const MachOObject::LoadCommandInfo *SymtabLCI = 0;
+  for (unsigned i = 0; i != Header.NumLoadCommands; ++i) {
+    const MachOObject::LoadCommandInfo &LCI = MachOObj->getLoadCommandInfo(i);
+    switch (LCI.Command.Type) {
+    case macho::LCT_Symtab:
+      SymtabLCI = &LCI;
+      break;
+    }
+  }
+
+  // Read and register the symbol table data.
+  InMemoryStruct<macho::SymtabLoadCommand> SymtabLC;
+  MachOObj->ReadSymtabLoadCommand(*SymtabLCI, SymtabLC);
+  MachOObj->RegisterStringTable(*SymtabLC);
+
+  std::vector<Section> Sections;
+  std::vector<Symbol> Symbols;
+  std::vector<Symbol> UnsortedSymbols; // FIXME: duplication
+  SmallVector<uint64_t, 8> FoundFns;
+
+  for (unsigned i = 0; i != Header.NumLoadCommands; ++i) {
+    const MachOObject::LoadCommandInfo &LCI = MachOObj->getLoadCommandInfo(i);
+    if (LCI.Command.Type == macho::LCT_Segment) {
+      InMemoryStruct<macho::SegmentLoadCommand> SegmentLC;
+      MachOObj->ReadSegmentLoadCommand(LCI, SegmentLC);
+
+      for (unsigned SectNum = 0; SectNum != SegmentLC->NumSections; ++SectNum) {
+        InMemoryStruct<macho::Section> Sect;
+        MachOObj->ReadSection(LCI, SectNum, Sect);
+
+        Section S;
+        memcpy(S.Name, Sect->Name, 16);
+        S.Address = Sect->Address;
+        S.Size = Sect->Size;
+        S.Offset = Sect->Offset;
+        S.NumRelocs = Sect->NumRelocationTableEntries;
+        S.RelocTableOffset = Sect->RelocationTableOffset;
+        Sections.push_back(S);
+
+        for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
+          InMemoryStruct<macho::SymbolTableEntry> STE;
+          MachOObj->ReadSymbolTableEntry(SymtabLC->SymbolTableOffset, i, STE);
+
+          Symbol S;
+          S.StringIndex = STE->StringIndex;
+          S.SectionIndex = STE->SectionIndex;
+          S.Value = STE->Value;
+          Symbols.push_back(S);
+          UnsortedSymbols.push_back(Symbols.back());
+        }
+      }
+    } else if (LCI.Command.Type == macho::LCT_Segment64) {
+      InMemoryStruct<macho::Segment64LoadCommand> Segment64LC;
+      MachOObj->ReadSegment64LoadCommand(LCI, Segment64LC);
+
+      for (unsigned SectNum = 0; SectNum != Segment64LC->NumSections; ++SectNum) {
+        InMemoryStruct<macho::Section64> Sect64;
+        MachOObj->ReadSection64(LCI, SectNum, Sect64);
+
+        Section S;
+        memcpy(S.Name, Sect64->Name, 16);
+        S.Address = Sect64->Address;
+        S.Size = Sect64->Size;
+        S.Offset = Sect64->Offset;
+        S.NumRelocs = Sect64->NumRelocationTableEntries;
+        S.RelocTableOffset = Sect64->RelocationTableOffset;
+        Sections.push_back(S);
+
+        for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
+          InMemoryStruct<macho::Symbol64TableEntry> STE;
+          MachOObj->ReadSymbol64TableEntry(SymtabLC->SymbolTableOffset, i, STE);
+
+          Symbol S;
+          S.StringIndex = STE->StringIndex;
+          S.SectionIndex = STE->SectionIndex;
+          S.Value = STE->Value;
+          Symbols.push_back(S);
+          UnsortedSymbols.push_back(Symbols.back());
+        }
+      }
+    } else if (LCI.Command.Type == macho::LCT_FunctionStarts) {
+      InMemoryStruct<macho::LinkeditDataLoadCommand> LLC;
+      MachOObj->ReadLinkeditDataLoadCommand(LCI, LLC);
+
+      MachOObj->ReadULEB128s(LLC->DataOffset, FoundFns);
+    }
+  }
+
+  std::map<uint64_t, MCFunction*> FunctionMap;
+
+  // Sort the symbols by address, just in case they didn't come in that way.
+  array_pod_sort(Symbols.begin(), Symbols.end());
+
+#ifndef NDEBUG
+  raw_ostream &DebugOut = DebugFlag ? dbgs() : nulls();
+#else
+  raw_ostream &DebugOut = nulls();
+#endif
+
+  SmallVector<MCFunction, 16> Functions;
+
+  for (unsigned SectIdx = 0; SectIdx != Sections.size(); SectIdx++) {
+    if (strcmp(Sections[SectIdx].Name, "__text"))
+      continue;
+
+    uint64_t VMAddr = Sections[SectIdx].Address - Sections[SectIdx].Offset;
+    for (unsigned i = 0, e = FoundFns.size(); i != e; ++i)
+      FunctionMap.insert(std::pair<uint64_t,MCFunction*>(FoundFns[i]+VMAddr,0));
+
+    StringRef Bytes = MachOObj->getData(Sections[SectIdx].Offset,
+                                        Sections[SectIdx].Size);
+    StringRefMemoryObject memoryObject(Bytes);
+    bool symbolTableWorked = false;
+
+    std::vector<std::pair<uint64_t, uint32_t> > Relocs;
+    for (unsigned j = 0; j != Sections[SectIdx].NumRelocs; ++j) {
+      InMemoryStruct<macho::RelocationEntry> RE;
+      MachOObj->ReadRelocationEntry(Sections[SectIdx].RelocTableOffset, j, RE);
+      Relocs.push_back(std::make_pair(RE->Word0, RE->Word1 & 0xffffff));
+    }
+    array_pod_sort(Relocs.begin(), Relocs.end());
+
+    for (unsigned SymIdx = 0; SymIdx != Symbols.size(); SymIdx++) {
+      if ((unsigned)Symbols[SymIdx].SectionIndex - 1 != SectIdx)
+        continue;
+
+      uint64_t Start = Symbols[SymIdx].Value - Sections[SectIdx].Address;
+      uint64_t End = (SymIdx+1 == Symbols.size() ||
+          Symbols[SymIdx].SectionIndex != Symbols[SymIdx+1].SectionIndex) ?
+          Sections[SectIdx].Size :
+          Symbols[SymIdx+1].Value - Sections[SectIdx].Address;
+      uint64_t Size;
+
+      if (Start >= End)
+        continue;
+
+      symbolTableWorked = true;
+
+      if (!CFG) {
+        outs() << MachOObj->getStringAtIndex(Symbols[SymIdx].StringIndex)
+          << ":\n";
+        for (uint64_t Index = Start; Index < End; Index += Size) {
+          MCInst Inst;
+
+          if (DisAsm->getInstruction(Inst, Size, memoryObject, Index,
+                                     DebugOut, nulls())) {
+            outs() << format("%8llx:\t", Sections[SectIdx].Address + Index);
+            DumpBytes(StringRef(Bytes.data() + Index, Size));
+            IP->printInst(&Inst, outs(), "");
+            outs() << "\n";
+          } else {
+            errs() << "llvm-objdump: warning: invalid instruction encoding\n";
+            if (Size == 0)
+              Size = 1; // skip illegible bytes
+          }
+        }
+      } else {
+        // Create CFG and use it for disassembly.
+        SmallVector<uint64_t, 16> Calls;
+        MCFunction f =
+          MCFunction::createFunctionFromMC(
+              MachOObj->getStringAtIndex(Symbols[SymIdx].StringIndex),
+              DisAsm.get(),
+              memoryObject, Start, End,
+              InstrAnalysis.get(), DebugOut,
+              Calls);
+
+        Functions.push_back(f);
+        FunctionMap[Start] = &Functions.back();
+
+        for (unsigned i = 0, e = Calls.size(); i != e; ++i)
+          FunctionMap.insert(std::pair<uint64_t, MCFunction*>(Calls[i], 0));
+      }
+    }
+
+    if (CFG) {
+      if (!symbolTableWorked) {
+        // Create CFG and use it for disassembly.
+        SmallVector<uint64_t, 16> Calls;
+        MCFunction f =
+          MCFunction::createFunctionFromMC("__TEXT", DisAsm.get(),
+              memoryObject, 0, Sections[SectIdx].Size,
+              InstrAnalysis.get(), DebugOut,
+              Calls);
+
+        Functions.push_back(f);
+        FunctionMap[Sections[SectIdx].Offset] = &Functions.back();
+
+        for (unsigned i = 0, e = Calls.size(); i != e; ++i)
+          FunctionMap.insert(std::pair<uint64_t, MCFunction*>(Calls[i], 0));
+      }
+      for (std::map<uint64_t, MCFunction*>::iterator mi = FunctionMap.begin(),
+           me = FunctionMap.end(); mi != me; ++mi)
+        if (mi->second == 0) {
+          SmallVector<uint64_t, 16> Calls;
+          MCFunction f =
+            MCFunction::createFunctionFromMC("unknown", DisAsm.get(),
+                                             memoryObject, mi->first,
+                                             Sections[SectIdx].Size,
+                                             InstrAnalysis.get(), DebugOut,
+                                             Calls);
+          Functions.push_back(f);
+          mi->second = &Functions.back();
+          for (unsigned i = 0, e = Calls.size(); i != e; ++i)
+            if (FunctionMap.insert(std::pair<uint64_t, MCFunction*>(Calls[i],0))
+                                                                        .second)
+              mi = FunctionMap.begin();
+        }
+
+      DenseSet<uint64_t> PrintedBlocks;
+      for (unsigned ffi = 0, ffe = Functions.size(); ffi != ffe; ++ffi) {
+        MCFunction &f = Functions[ffi];
+        for (MCFunction::iterator fi = f.begin(), fe = f.end(); fi != fe; ++fi){
+          if (!PrintedBlocks.insert(fi->first).second)
+            continue;
+          bool hasPreds = FunctionMap.find(fi->first) != FunctionMap.end();
+
+          // Only print blocks that have predecessors.
+          // FIXME: Slow.
+          for (MCFunction::iterator pi = f.begin(), pe = f.end(); pi != pe;
+              ++pi)
+            if (pi->second.contains(fi->first)) {
+              hasPreds = true;
+              break;
+            }
+
+          // Data block.
+          if (!hasPreds && fi != f.begin()) {
+            uint64_t End = llvm::next(fi) == fe ? Sections[SectIdx].Size :
+                                                  llvm::next(fi)->first;
+            outs() << "# " << End-fi->first << " bytes of data:\n";
+            for (unsigned pos = fi->first; pos != End; ++pos) {
+              outs() << format("%8x:\t", Sections[SectIdx].Address + pos);
+              DumpBytes(StringRef(Bytes.data() + pos, 1));
+              outs() << format("\t.byte 0x%02x\n", (uint8_t)Bytes[pos]);
+            }
+            continue;
+          }
+
+          if (fi->second.contains(fi->first))
+            outs() << "# Loop begin:\n";
+
+          for (unsigned ii = 0, ie = fi->second.getInsts().size(); ii != ie;
+               ++ii) {
+            const MCDecodedInst &Inst = fi->second.getInsts()[ii];
+            if (FunctionMap.find(Sections[SectIdx].Address + Inst.Address) !=
+                FunctionMap.end())
+              outs() << FunctionMap[Sections[SectIdx].Address + Inst.Address]->
+                                                             getName() << ":\n";
+            outs() << format("%8llx:\t", Sections[SectIdx].Address +
+                                         Inst.Address);
+            DumpBytes(StringRef(Bytes.data() + Inst.Address, Inst.Size));
+            // Simple loops.
+            if (fi->second.contains(fi->first))
+              outs() << '\t';
+            IP->printInst(&Inst.Inst, outs(), "");
+            for (unsigned j = 0; j != Relocs.size(); ++j)
+              if (Relocs[j].first >= Sections[SectIdx].Address + Inst.Address &&
+                  Relocs[j].first < Sections[SectIdx].Address + Inst.Address +
+                                    Inst.Size) {
+                outs() << "\t# "
+                   << MachOObj->getStringAtIndex(
+                                  UnsortedSymbols[Relocs[j].second].StringIndex)
+                   << ' ';
+                DumpAddress(UnsortedSymbols[Relocs[j].second].Value, Sections,
+                            MachOObj.get(), outs());
+              }
+            uint64_t targ = InstrAnalysis->evaluateBranch(Inst.Inst,
+                                                          Inst.Address,
+                                                          Inst.Size);
+            if (targ != -1ULL)
+              DumpAddress(targ, Sections, MachOObj.get(), outs());
+
+            outs() << '\n';
+          }
+        }
+
+        // Start a new dot file.
+        std::string Error;
+        raw_fd_ostream Out((f.getName().str() + ".dot").c_str(), Error);
+        if (!Error.empty()) {
+          errs() << "llvm-objdump: warning: " << Error << '\n';
+          continue;
+        }
+
+        Out << "digraph " << f.getName() << " {\n";
+        Out << "graph [ rankdir = \"LR\" ];\n";
+        for (MCFunction::iterator i = f.begin(), e = f.end(); i != e; ++i) {
+          bool hasPreds = false;
+          // Only print blocks that have predecessors.
+          // FIXME: Slow.
+          for (MCFunction::iterator pi = f.begin(), pe = f.end(); pi != pe;
+               ++pi)
+            if (pi->second.contains(i->first)) {
+              hasPreds = true;
+              break;
+            }
+
+          if (!hasPreds && i != f.begin())
+            continue;
+
+          Out << '"' << i->first << "\" [ label=\"<a>";
+          // Print instructions.
+          for (unsigned ii = 0, ie = i->second.getInsts().size(); ii != ie;
+               ++ii) {
+            // Escape special chars and print the instruction in mnemonic form.
+            std::string Str;
+            raw_string_ostream OS(Str);
+            IP->printInst(&i->second.getInsts()[ii].Inst, OS, "");
+            Out << DOT::EscapeString(OS.str()) << '|';
+          }
+          Out << "<o>\" shape=\"record\" ];\n";
+
+          // Add edges.
+          for (MCBasicBlock::succ_iterator si = i->second.succ_begin(),
+              se = i->second.succ_end(); si != se; ++si)
+            Out << i->first << ":o -> " << *si <<":a\n";
+        }
+        Out << "}\n";
+      }
+    }
+  }
+}
diff --git a/tools/llvm-objdump/llvm-objdump.cpp b/tools/llvm-objdump/llvm-objdump.cpp
index 4cfd4f4..78824e9 100644
--- a/tools/llvm-objdump/llvm-objdump.cpp
+++ b/tools/llvm-objdump/llvm-objdump.cpp
@@ -13,6 +13,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm-objdump.h"
 #include "MCFunction.h"
 #include "llvm/Object/ObjectFile.h"
 #include "llvm/ADT/OwningPtr.h"
@@ -46,39 +47,37 @@
 using namespace llvm;
 using namespace object;
 
-namespace {
-  cl::list<std::string>
-  InputFilenames(cl::Positional, cl::desc("<input object files>"),
-                 cl::ZeroOrMore);
+static cl::list<std::string>
+InputFilenames(cl::Positional, cl::desc("<input object files>"),cl::ZeroOrMore);
 
-  cl::opt<bool>
-  Disassemble("disassemble",
-    cl::desc("Display assembler mnemonics for the machine instructions"));
-  cl::alias
-  Disassembled("d", cl::desc("Alias for --disassemble"),
-               cl::aliasopt(Disassemble));
+static cl::opt<bool>
+Disassemble("disassemble",
+  cl::desc("Display assembler mnemonics for the machine instructions"));
+static cl::alias
+Disassembled("d", cl::desc("Alias for --disassemble"),
+             cl::aliasopt(Disassemble));
 
-  cl::opt<bool>
-  CFG("cfg", cl::desc("Create a CFG for every symbol in the object file and"
-                      "write it to a graphviz file"));
+static cl::opt<bool>
+MachO("macho", cl::desc("Use MachO specific object file parser"));
+static cl::alias
+MachOm("m", cl::desc("Alias for --macho"), cl::aliasopt(MachO));
 
-  cl::opt<std::string>
-  TripleName("triple", cl::desc("Target triple to disassemble for, "
-                                "see -version for available targets"));
+cl::opt<std::string>
+llvm::TripleName("triple", cl::desc("Target triple to disassemble for, "
+                                    "see -version for available targets"));
 
-  cl::opt<std::string>
-  ArchName("arch", cl::desc("Target arch to disassemble for, "
-                            "see -version for available targets"));
+cl::opt<std::string>
+llvm::ArchName("arch", cl::desc("Target arch to disassemble for, "
+                                "see -version for available targets"));
 
-  StringRef ToolName;
+static StringRef ToolName;
 
-  bool error(error_code ec) {
-    if (!ec) return false;
+static bool error(error_code ec) {
+  if (!ec) return false;
 
-    outs() << ToolName << ": error reading file: " << ec.message() << ".\n";
-    outs().flush();
-    return true;
-  }
+  outs() << ToolName << ": error reading file: " << ec.message() << ".\n";
+  outs().flush();
+  return true;
 }
 
 static const Target *GetTarget(const ObjectFile *Obj = NULL) {
@@ -106,27 +105,8 @@ static const Target *GetTarget(const ObjectFile *Obj = NULL) {
   return 0;
 }
 
-namespace {
-class StringRefMemoryObject : public MemoryObject {
-private:
-  StringRef Bytes;
-public:
-  StringRefMemoryObject(StringRef bytes) : Bytes(bytes) {}
-
-  uint64_t getBase() const { return 0; }
-  uint64_t getExtent() const { return Bytes.size(); }
-
-  int readByte(uint64_t Addr, uint8_t *Byte) const {
-    if (Addr >= getExtent())
-      return -1;
-    *Byte = Bytes[Addr];
-    return 0;
-  }
-};
-}
-
-static void DumpBytes(StringRef bytes) {
-  static char hex_rep[] = "0123456789abcdef";
+void llvm::DumpBytes(StringRef bytes) {
+  static const char hex_rep[] = "0123456789abcdef";
   // FIXME: The real way to do this is to figure out the longest instruction
   //        and align to that size before printing. I'll fix this when I get
   //        around to outputting relocations.
@@ -151,7 +131,7 @@ static void DumpBytes(StringRef bytes) {
   outs() << output;
 }
 
-static void DisassembleInput(const StringRef &Filename) {
+void llvm::DisassembleInputLibObject(StringRef Filename) {
   OwningPtr<MemoryBuffer> Buff;
 
   if (error_code ec = MemoryBuffer::getFileOrSTDIN(Filename, Buff)) {
@@ -259,118 +239,22 @@ static void DisassembleInput(const StringRef &Filename) {
         raw_ostream &DebugOut = nulls();
 #endif
 
-      if (!CFG) {
-        for (Index = Start; Index < End; Index += Size) {
-          MCInst Inst;
-
-          if (DisAsm->getInstruction(Inst, Size, memoryObject, Index,
-                                     DebugOut, nulls())) {
-            uint64_t addr;
-            if (error(i->getAddress(addr))) break;
-            outs() << format("%8x:\t", addr + Index);
-            DumpBytes(StringRef(Bytes.data() + Index, Size));
-            IP->printInst(&Inst, outs(), "");
-            outs() << "\n";
-          } else {
-            errs() << ToolName << ": warning: invalid instruction encoding\n";
-            if (Size == 0)
-              Size = 1; // skip illegible bytes
-          }
-        }
-
-      } else {
-        // Create CFG and use it for disassembly.
-        MCFunction f =
-          MCFunction::createFunctionFromMC(Symbols[si].second, DisAsm.get(),
-                                           memoryObject, Start, End,
-                                           InstrAnalysis.get(), DebugOut);
-
-        for (MCFunction::iterator fi = f.begin(), fe = f.end(); fi != fe; ++fi){
-          bool hasPreds = false;
-          // Only print blocks that have predecessors.
-          // FIXME: Slow.
-          for (MCFunction::iterator pi = f.begin(), pe = f.end(); pi != pe;
-              ++pi)
-            if (pi->second.contains(&fi->second)) {
-              hasPreds = true;
-              break;
-            }
-
-          // Data block.
-          if (!hasPreds && fi != f.begin()) {
-            uint64_t End = llvm::next(fi) == fe ? SectSize :
-                                                  llvm::next(fi)->first;
-            uint64_t addr;
-            if (error(i->getAddress(addr))) break;
-            outs() << "# " << End-fi->first << " bytes of data:\n";
-            for (unsigned pos = fi->first; pos != End; ++pos) {
-              outs() << format("%8x:\t", addr + pos);
-              DumpBytes(StringRef(Bytes.data() + pos, 1));
-              outs() << format("\t.byte 0x%02x\n", (uint8_t)Bytes[pos]);
-            }
-            continue;
-          }
-
-          if (fi->second.contains(&fi->second))
-            outs() << "# Loop begin:\n";
-
-          for (unsigned ii = 0, ie = fi->second.getInsts().size(); ii != ie;
-               ++ii) {
-            uint64_t addr;
-            if (error(i->getAddress(addr))) break;
-            const MCDecodedInst &Inst = fi->second.getInsts()[ii];
-            outs() << format("%8x:\t", addr + Inst.Address);
-            DumpBytes(StringRef(Bytes.data() + Inst.Address, Inst.Size));
-            // Simple loops.
-            if (fi->second.contains(&fi->second))
-              outs() << '\t';
-            IP->printInst(&Inst.Inst, outs(), "");
-            outs() << '\n';
-          }
-        }
-
-        // Start a new dot file.
-        std::string Error;
-        raw_fd_ostream Out((f.getName().str() + ".dot").c_str(), Error);
-        if (!Error.empty()) {
-          errs() << ToolName << ": warning: " << Error << '\n';
-          continue;
-        }
-
-        Out << "digraph " << f.getName() << " {\n";
-        Out << "graph [ rankdir = \"LR\" ];\n";
-        for (MCFunction::iterator i = f.begin(), e = f.end(); i != e; ++i) {
-          bool hasPreds = false;
-          // Only print blocks that have predecessors.
-          // FIXME: Slow.
-          for (MCFunction::iterator pi = f.begin(), pe = f.end(); pi != pe;
-               ++pi)
-            if (pi->second.contains(&i->second)) {
-              hasPreds = true;
-              break;
-            }
-
-          if (!hasPreds && i != f.begin())
-            continue;
-
-          Out << '"' << (uintptr_t)&i->second << "\" [ label=\"<a>";
-          // Print instructions.
-          for (unsigned ii = 0, ie = i->second.getInsts().size(); ii != ie;
-               ++ii) {
-            // Escape special chars and print the instruction in mnemonic form.
-            std::string Str;
-            raw_string_ostream OS(Str);
-            IP->printInst(&i->second.getInsts()[ii].Inst, OS, "");
-            Out << DOT::EscapeString(OS.str()) << '|';
-          }
-          Out << "<o>\" shape=\"record\" ];\n";
-
-          // Add edges.
-          for (MCBasicBlock::succ_iterator si = i->second.succ_begin(),
-              se = i->second.succ_end(); si != se; ++si)
-            Out << (uintptr_t)&i->second << ":o -> " << (uintptr_t)*si <<":a\n";
+      for (Index = Start; Index < End; Index += Size) {
+        MCInst Inst;
+
+        if (DisAsm->getInstruction(Inst, Size, memoryObject, Index,
+                                   DebugOut, nulls())) {
+          uint64_t addr;
+          if (error(i->getAddress(addr))) break;
+          outs() << format("%8x:\t", addr + Index);
+          DumpBytes(StringRef(Bytes.data() + Index, Size));
+          IP->printInst(&Inst, outs(), "");
+          outs() << "\n";
+        } else {
+          errs() << ToolName << ": warning: invalid instruction encoding\n";
+          if (Size == 0)
+            Size = 1; // skip illegible bytes
         }
-        Out << "}\n";
       }
     }
   }
@@ -404,8 +288,12 @@ int main(int argc, char **argv) {
     return 2;
   }
 
-  std::for_each(InputFilenames.begin(), InputFilenames.end(),
-                DisassembleInput);
+  if (MachO)
+    std::for_each(InputFilenames.begin(), InputFilenames.end(),
+                  DisassembleInputMachO);
+  else
+    std::for_each(InputFilenames.begin(), InputFilenames.end(),
+                  DisassembleInputLibObject);
 
   return 0;
 }
diff --git a/tools/llvm-objdump/llvm-objdump.h b/tools/llvm-objdump/llvm-objdump.h
new file mode 100644
index 0000000..63108d5
--- /dev/null
+++ b/tools/llvm-objdump/llvm-objdump.h
@@ -0,0 +1,47 @@
+//===-- llvm-objdump.h ----------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_OBJDUMP_H
+#define LLVM_OBJDUMP_H
+
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/DataTypes.h"
+#include "llvm/Support/MemoryObject.h"
+
+namespace llvm {
+
+extern cl::opt<std::string> TripleName;
+extern cl::opt<std::string> ArchName;
+
+// Various helper functions.
+void DumpBytes(StringRef bytes);
+void DisassembleInputLibObject(StringRef Filename);
+void DisassembleInputMachO(StringRef Filename);
+
+class StringRefMemoryObject : public MemoryObject {
+private:
+  StringRef Bytes;
+public:
+  StringRefMemoryObject(StringRef bytes) : Bytes(bytes) {}
+
+  uint64_t getBase() const { return 0; }
+  uint64_t getExtent() const { return Bytes.size(); }
+
+  int readByte(uint64_t Addr, uint8_t *Byte) const {
+    if (Addr >= getExtent())
+      return -1;
+    *Byte = Bytes[Addr];
+    return 0;
+  }
+};
+
+}
+
+#endif