Update LLVM to r104832.

18 files changed, 507 insertions, 226 deletions

diff --git a/include/llvm/MC/MCAsmInfo.h b/include/llvm/MC/MCAsmInfo.h
index f57f642..8516de0 100644
--- a/include/llvm/MC/MCAsmInfo.h
+++ b/include/llvm/MC/MCAsmInfo.h
@@ -41,6 +41,10 @@ namespace llvm {
     /// the macho-specific .zerofill directive for emitting BSS Symbols.
     bool HasMachoZeroFillDirective;               // Default is false.
     
+    /// HasMachoTBSSDirective - True if this is a MachO target that supports
+    /// the macho-specific .tbss directive for emitting thread local BSS Symbols
+    bool HasMachoTBSSDirective;                 // Default is false.
+    
     /// HasStaticCtorDtorReferenceInStaticMode - True if the compiler should
     /// emit a ".reference .constructors_used" or ".reference .destructors_used"
     /// directive after the a static ctor/dtor list.  This directive is only
@@ -303,6 +307,7 @@ namespace llvm {
     // Accessors.
     //
     bool hasMachoZeroFillDirective() const { return HasMachoZeroFillDirective; }
+    bool hasMachoTBSSDirective() const { return HasMachoTBSSDirective; }
     bool hasStaticCtorDtorReferenceInStaticMode() const {
       return HasStaticCtorDtorReferenceInStaticMode;
     }
diff --git a/include/llvm/MC/MCAsmLayout.h b/include/llvm/MC/MCAsmLayout.h
index ebf0520..b9565ba 100644
--- a/include/llvm/MC/MCAsmLayout.h
+++ b/include/llvm/MC/MCAsmLayout.h
@@ -10,6 +10,8 @@
 #ifndef LLVM_MC_MCASMLAYOUT_H
 #define LLVM_MC_MCASMLAYOUT_H
 
+#include "llvm/ADT/SmallVector.h"
+
 namespace llvm {
 class MCAssembler;
 class MCFragment;
@@ -24,11 +26,30 @@ class MCSymbolData;
 /// efficiently compute the exact addresses of any symbol in the assembly file,
 /// even during the relaxation process.
 class MCAsmLayout {
+public:
+  typedef llvm::SmallVectorImpl<MCSectionData*>::const_iterator const_iterator;
+  typedef llvm::SmallVectorImpl<MCSectionData*>::iterator iterator;
+
 private:
   MCAssembler &Assembler;
 
+  /// List of sections in layout order.
+  llvm::SmallVector<MCSectionData*, 16> SectionOrder;
+
+  /// The last fragment which was layed out, or 0 if nothing has been layed
+  /// out. Fragments are always layed out in order, so all fragments with a
+  /// lower ordinal will be up to date.
+  mutable MCFragment *LastValidFragment;
+
+  /// \brief Make sure that the layout for the given fragment is valid, lazily
+  /// computing it if necessary.
+  void EnsureValid(const MCFragment *F) const;
+
+  bool isSectionUpToDate(const MCSectionData *SD) const;
+  bool isFragmentUpToDate(const MCFragment *F) const;
+
 public:
-  MCAsmLayout(MCAssembler &_Assembler) : Assembler(_Assembler) {}
+  MCAsmLayout(MCAssembler &_Assembler);
 
   /// Get the assembler object this is a layout for.
   MCAssembler &getAssembler() const { return Assembler; }
@@ -38,6 +59,33 @@ public:
   /// the delta from the old size.
   void UpdateForSlide(MCFragment *F, int SlideAmount);
 
+  /// \brief Update the layout because a fragment has been replaced.
+  void FragmentReplaced(MCFragment *Src, MCFragment *Dst);
+
+  /// \brief Perform a full layout.
+  void LayoutFile();
+
+  /// \brief Perform layout for a single fragment, assuming that the previous
+  /// fragment has already been layed out correctly, and the parent section has
+  /// been initialized.
+  void LayoutFragment(MCFragment *Fragment);
+
+  /// \brief Performs initial layout for a single section, assuming that the
+  /// previous section (including its fragments) has already been layed out
+  /// correctly.
+  void LayoutSection(MCSectionData *SD);
+
+  /// @name Section Access (in layout order)
+  /// @{
+
+  llvm::SmallVectorImpl<MCSectionData*> &getSectionOrder() {
+    return SectionOrder;
+  }
+  const llvm::SmallVectorImpl<MCSectionData*> &getSectionOrder() const {
+    return SectionOrder;
+  }
+
+  /// @}
   /// @name Fragment Layout Data
   /// @{
 
@@ -45,15 +93,9 @@ public:
   /// current layout.
   uint64_t getFragmentEffectiveSize(const MCFragment *F) const;
 
-  /// \brief Set the effective size of the given fragment.
-  void setFragmentEffectiveSize(MCFragment *F, uint64_t Value);
-
   /// \brief Get the offset of the given fragment inside its containing section.
   uint64_t getFragmentOffset(const MCFragment *F) const;
 
-  /// \brief Set the offset of the given fragment inside its containing section.
-  void setFragmentOffset(MCFragment *F, uint64_t Value);
-
   /// @}
   /// @name Section Layout Data
   /// @{
@@ -61,22 +103,6 @@ public:
   /// \brief Get the computed address of the given section.
   uint64_t getSectionAddress(const MCSectionData *SD) const;
 
-  /// \brief Set the computed address of the given section.
-  void setSectionAddress(MCSectionData *SD, uint64_t Value);
-
-  /// \brief Get the data size of the given section, as emitted to the object
-  /// file. This may include additional padding, or be 0 for virtual sections.
-  uint64_t getSectionFileSize(const MCSectionData *SD) const;
-
-  /// \brief Set the data size of the given section.
-  void setSectionFileSize(MCSectionData *SD, uint64_t Value);
-
-  /// \brief Get the actual data size of the given section.
-  uint64_t getSectionSize(const MCSectionData *SD) const;
-
-  /// \brief Set the actual data size of the given section.
-  void setSectionSize(MCSectionData *SD, uint64_t Value);
-
   /// @}
   /// @name Utility Functions
   /// @{
@@ -85,6 +111,18 @@ public:
   /// layout.
   uint64_t getFragmentAddress(const MCFragment *F) const;
 
+  /// \brief Get the address space size of the given section, as it effects
+  /// layout. This may differ from the size reported by \see getSectionSize() by
+  /// not including section tail padding.
+  uint64_t getSectionAddressSize(const MCSectionData *SD) const;
+
+  /// \brief Get the data size of the given section, as emitted to the object
+  /// file. This may include additional padding, or be 0 for virtual sections.
+  uint64_t getSectionFileSize(const MCSectionData *SD) const;
+
+  /// \brief Get the logical data size of the given section.
+  uint64_t getSectionSize(const MCSectionData *SD) const;
+
   /// \brief Get the address of the given symbol, as computed in the current
   /// layout.
   uint64_t getSymbolAddress(const MCSymbolData *SD) const;
diff --git a/include/llvm/MC/MCAssembler.h b/include/llvm/MC/MCAssembler.h
index c1b60f0..d9963ec 100644
--- a/include/llvm/MC/MCAssembler.h
+++ b/include/llvm/MC/MCAssembler.h
@@ -32,30 +32,10 @@ class MCObjectWriter;
 class MCSection;
 class MCSectionData;
 class MCSymbol;
+class MCSymbolData;
 class MCValue;
 class TargetAsmBackend;
 
-/// MCAsmFixup - Represent a fixed size region of bytes inside some fragment
-/// which needs to be rewritten. This region will either be rewritten by the
-/// assembler or cause a relocation entry to be generated.
-//
-// FIXME: This should probably just be merged with MCFixup.
-class MCAsmFixup {
-public:
-  /// Offset - The offset inside the fragment which needs to be rewritten.
-  uint64_t Offset;
-
-  /// Value - The expression to eventually write into the fragment.
-  const MCExpr *Value;
-
-  /// Kind - The fixup kind.
-  MCFixupKind Kind;
-
-public:
-  MCAsmFixup(uint64_t _Offset, const MCExpr &_Value, MCFixupKind _Kind)
-    : Offset(_Offset), Value(&_Value), Kind(_Kind) {}
-};
-
 class MCFragment : public ilist_node<MCFragment> {
   friend class MCAsmLayout;
 
@@ -68,8 +48,7 @@ public:
     FT_Data,
     FT_Fill,
     FT_Inst,
-    FT_Org,
-    FT_ZeroFill
+    FT_Org
   };
 
 private:
@@ -78,6 +57,11 @@ private:
   /// Parent - The data for the section this fragment is in.
   MCSectionData *Parent;
 
+  /// Atom - The atom this fragment is in, as represented by it's defining
+  /// symbol. Atom's are only used by backends which set
+  /// \see MCAsmBackend::hasReliableSymbolDifference().
+  MCSymbolData *Atom;
+
   /// @name Assembler Backend Data
   /// @{
   //
@@ -91,9 +75,9 @@ private:
   /// initialized.
   uint64_t EffectiveSize;
 
-  /// Ordinal - The global index of this fragment. This is the index across all
-  /// sections, not just the parent section.
-  unsigned Ordinal;
+  /// LayoutOrder - The global layout order of this fragment. This is the index
+  /// across all fragments in the file, not just within the section.
+  unsigned LayoutOrder;
 
   /// @}
 
@@ -103,30 +87,32 @@ protected:
 public:
   // Only for sentinel.
   MCFragment();
-  virtual ~MCFragment();
 
   FragmentType getKind() const { return Kind; }
 
   MCSectionData *getParent() const { return Parent; }
   void setParent(MCSectionData *Value) { Parent = Value; }
 
-  unsigned getOrdinal() const { return Ordinal; }
-  void setOrdinal(unsigned Value) { Ordinal = Value; }
+  MCSymbolData *getAtom() const { return Atom; }
+  void setAtom(MCSymbolData *Value) { Atom = Value; }
+
+  unsigned getLayoutOrder() const { return LayoutOrder; }
+  void setLayoutOrder(unsigned Value) { LayoutOrder = Value; }
 
   static bool classof(const MCFragment *O) { return true; }
 
-  virtual void dump();
+  void dump();
 };
 
 class MCDataFragment : public MCFragment {
   SmallString<32> Contents;
 
   /// Fixups - The list of fixups in this fragment.
-  std::vector<MCAsmFixup> Fixups;
+  std::vector<MCFixup> Fixups;
 
 public:
-  typedef std::vector<MCAsmFixup>::const_iterator const_fixup_iterator;
-  typedef std::vector<MCAsmFixup>::iterator fixup_iterator;
+  typedef std::vector<MCFixup>::const_iterator const_fixup_iterator;
+  typedef std::vector<MCFixup>::iterator fixup_iterator;
 
 public:
   MCDataFragment(MCSectionData *SD = 0) : MCFragment(FT_Data, SD) {}
@@ -141,15 +127,15 @@ public:
   /// @name Fixup Access
   /// @{
 
-  void addFixup(MCAsmFixup Fixup) {
+  void addFixup(MCFixup Fixup) {
     // Enforce invariant that fixups are in offset order.
-    assert((Fixups.empty() || Fixup.Offset > Fixups.back().Offset) &&
+    assert((Fixups.empty() || Fixup.getOffset() > Fixups.back().getOffset()) &&
            "Fixups must be added in order!");
     Fixups.push_back(Fixup);
   }
 
-  std::vector<MCAsmFixup> &getFixups() { return Fixups; }
-  const std::vector<MCAsmFixup> &getFixups() const { return Fixups; }
+  std::vector<MCFixup> &getFixups() { return Fixups; }
+  const std::vector<MCFixup> &getFixups() const { return Fixups; }
 
   fixup_iterator fixup_begin() { return Fixups.begin(); }
   const_fixup_iterator fixup_begin() const { return Fixups.begin(); }
@@ -165,8 +151,6 @@ public:
     return F->getKind() == MCFragment::FT_Data;
   }
   static bool classof(const MCDataFragment *) { return true; }
-
-  virtual void dump();
 };
 
 // FIXME: This current incarnation of MCInstFragment doesn't make much sense, as
@@ -182,11 +166,11 @@ class MCInstFragment : public MCFragment {
   SmallString<8> Code;
 
   /// Fixups - The list of fixups in this fragment.
-  SmallVector<MCAsmFixup, 1> Fixups;
+  SmallVector<MCFixup, 1> Fixups;
 
 public:
-  typedef SmallVectorImpl<MCAsmFixup>::const_iterator const_fixup_iterator;
-  typedef SmallVectorImpl<MCAsmFixup>::iterator fixup_iterator;
+  typedef SmallVectorImpl<MCFixup>::const_iterator const_fixup_iterator;
+  typedef SmallVectorImpl<MCFixup>::iterator fixup_iterator;
 
 public:
   MCInstFragment(MCInst _Inst, MCSectionData *SD = 0)
@@ -210,8 +194,8 @@ public:
   /// @name Fixup Access
   /// @{
 
-  SmallVectorImpl<MCAsmFixup> &getFixups() { return Fixups; }
-  const SmallVectorImpl<MCAsmFixup> &getFixups() const { return Fixups; }
+  SmallVectorImpl<MCFixup> &getFixups() { return Fixups; }
+  const SmallVectorImpl<MCFixup> &getFixups() const { return Fixups; }
 
   fixup_iterator fixup_begin() { return Fixups.begin(); }
   const_fixup_iterator fixup_begin() const { return Fixups.begin(); }
@@ -227,8 +211,6 @@ public:
     return F->getKind() == MCFragment::FT_Inst;
   }
   static bool classof(const MCInstFragment *) { return true; }
-
-  virtual void dump();
 };
 
 class MCAlignFragment : public MCFragment {
@@ -245,17 +227,24 @@ class MCAlignFragment : public MCFragment {
   /// cannot be satisfied in this width then this fragment is ignored.
   unsigned MaxBytesToEmit;
 
-  /// EmitNops - true when aligning code and optimal nops to be used for
-  /// filling.
-  bool EmitNops;
+  /// EmitNops - Flag to indicate that (optimal) NOPs should be emitted instead
+  /// of using the provided value. The exact interpretation of this flag is
+  /// target dependent.
+  bool EmitNops : 1;
+
+  /// OnlyAlignAddress - Flag to indicate that this align is only used to adjust
+  /// the address space size of a section and that it should not be included as
+  /// part of the section size. This flag can only be used on the last fragment
+  /// in a section.
+  bool OnlyAlignAddress : 1;
 
 public:
   MCAlignFragment(unsigned _Alignment, int64_t _Value, unsigned _ValueSize,
-                  unsigned _MaxBytesToEmit, bool _EmitNops,
-		  MCSectionData *SD = 0)
+                  unsigned _MaxBytesToEmit, MCSectionData *SD = 0)
     : MCFragment(FT_Align, SD), Alignment(_Alignment),
       Value(_Value),ValueSize(_ValueSize),
-      MaxBytesToEmit(_MaxBytesToEmit), EmitNops(_EmitNops) {}
+      MaxBytesToEmit(_MaxBytesToEmit), EmitNops(false),
+      OnlyAlignAddress(false) {}
 
   /// @name Accessors
   /// @{
@@ -268,7 +257,11 @@ public:
 
   unsigned getMaxBytesToEmit() const { return MaxBytesToEmit; }
 
-  unsigned getEmitNops() const { return EmitNops; }
+  bool hasEmitNops() const { return EmitNops; }
+  void setEmitNops(bool Value) { EmitNops = Value; }
+
+  bool hasOnlyAlignAddress() const { return OnlyAlignAddress; }
+  void setOnlyAlignAddress(bool Value) { OnlyAlignAddress = Value; }
 
   /// @}
 
@@ -276,25 +269,27 @@ public:
     return F->getKind() == MCFragment::FT_Align;
   }
   static bool classof(const MCAlignFragment *) { return true; }
-
-  virtual void dump();
 };
 
 class MCFillFragment : public MCFragment {
   /// Value - Value to use for filling bytes.
   int64_t Value;
 
-  /// ValueSize - The size (in bytes) of \arg Value to use when filling.
+  /// ValueSize - The size (in bytes) of \arg Value to use when filling, or 0 if
+  /// this is a virtual fill fragment.
   unsigned ValueSize;
 
-  /// Count - The number of copies of \arg Value to insert.
-  uint64_t Count;
+  /// Size - The number of bytes to insert.
+  uint64_t Size;
 
 public:
-  MCFillFragment(int64_t _Value, unsigned _ValueSize, uint64_t _Count,
+  MCFillFragment(int64_t _Value, unsigned _ValueSize, uint64_t _Size,
                  MCSectionData *SD = 0)
     : MCFragment(FT_Fill, SD),
-      Value(_Value), ValueSize(_ValueSize), Count(_Count) {}
+      Value(_Value), ValueSize(_ValueSize), Size(_Size) {
+    assert((!ValueSize || (Size % ValueSize) == 0) &&
+           "Fill size must be a multiple of the value size!");
+  }
 
   /// @name Accessors
   /// @{
@@ -303,7 +298,7 @@ public:
 
   unsigned getValueSize() const { return ValueSize; }
 
-  uint64_t getCount() const { return Count; }
+  uint64_t getSize() const { return Size; }
 
   /// @}
 
@@ -311,8 +306,6 @@ public:
     return F->getKind() == MCFragment::FT_Fill;
   }
   static bool classof(const MCFillFragment *) { return true; }
-
-  virtual void dump();
 };
 
 class MCOrgFragment : public MCFragment {
@@ -340,39 +333,6 @@ public:
     return F->getKind() == MCFragment::FT_Org;
   }
   static bool classof(const MCOrgFragment *) { return true; }
-
-  virtual void dump();
-};
-
-/// MCZeroFillFragment - Represent data which has a fixed size and alignment,
-/// but requires no physical space in the object file.
-class MCZeroFillFragment : public MCFragment {
-  /// Size - The size of this fragment.
-  uint64_t Size;
-
-  /// Alignment - The alignment for this fragment.
-  unsigned Alignment;
-
-public:
-  MCZeroFillFragment(uint64_t _Size, unsigned _Alignment, MCSectionData *SD = 0)
-    : MCFragment(FT_ZeroFill, SD),
-      Size(_Size), Alignment(_Alignment) {}
-
-  /// @name Accessors
-  /// @{
-
-  uint64_t getSize() const { return Size; }
-
-  unsigned getAlignment() const { return Alignment; }
-
-  /// @}
-
-  static bool classof(const MCFragment *F) {
-    return F->getKind() == MCFragment::FT_ZeroFill;
-  }
-  static bool classof(const MCZeroFillFragment *) { return true; }
-
-  virtual void dump();
 };
 
 // FIXME: Should this be a separate class, or just merged into MCSection? Since
@@ -400,6 +360,9 @@ private:
   /// Ordinal - The section index in the assemblers section list.
   unsigned Ordinal;
 
+  /// LayoutOrder - The index of this section in the layout order.
+  unsigned LayoutOrder;
+
   /// Alignment - The maximum alignment seen in this section.
   unsigned Alignment;
 
@@ -412,13 +375,6 @@ private:
   /// initialized.
   uint64_t Address;
 
-  /// Size - The content size of this section. This is ~0 until initialized.
-  uint64_t Size;
-
-  /// FileSize - The size of this section in the object file. This is ~0 until
-  /// initialized.
-  uint64_t FileSize;
-
   /// HasInstructions - Whether this section has had instructions emitted into
   /// it.
   unsigned HasInstructions : 1;
@@ -441,6 +397,9 @@ public:
   unsigned getOrdinal() const { return Ordinal; }
   void setOrdinal(unsigned Value) { Ordinal = Value; }
 
+  unsigned getLayoutOrder() const { return LayoutOrder; }
+  void setLayoutOrder(unsigned Value) { LayoutOrder = Value; }
+
   /// @name Fragment Access
   /// @{
 
@@ -562,6 +521,11 @@ public:
   /// setFlags - Set the (implementation defined) symbol flags.
   void setFlags(uint32_t Value) { Flags = Value; }
 
+  /// modifyFlags - Modify the flags via a mask
+  void modifyFlags(uint32_t Value, uint32_t Mask) {
+    Flags = (Flags & ~Mask) | Value;
+  }
+
   /// getIndex - Get the (implementation defined) index.
   uint64_t getIndex() const { return Index; }
 
@@ -642,26 +606,23 @@ private:
   /// \arg Value result is fixed, otherwise the value may change due to
   /// relocation.
   bool EvaluateFixup(const MCAsmLayout &Layout,
-                     const MCAsmFixup &Fixup, const MCFragment *DF,
+                     const MCFixup &Fixup, const MCFragment *DF,
                      MCValue &Target, uint64_t &Value) const;
 
   /// Check whether a fixup can be satisfied, or whether it needs to be relaxed
   /// (increased in size, in order to hold its value correctly).
-  bool FixupNeedsRelaxation(const MCAsmFixup &Fixup, const MCFragment *DF,
+  bool FixupNeedsRelaxation(const MCFixup &Fixup, const MCFragment *DF,
                             const MCAsmLayout &Layout) const;
 
   /// Check whether the given fragment needs relaxation.
   bool FragmentNeedsRelaxation(const MCInstFragment *IF,
                                const MCAsmLayout &Layout) const;
 
-  /// LayoutSection - Assign the section the given \arg StartAddress, and then
-  /// assign offsets and sizes to the fragments in the section \arg SD, and
-  /// update the section size.
-  ///
-  /// \return The address at the end of the section, for use in laying out the
-  /// succeeding section.
-  uint64_t LayoutSection(MCSectionData &SD, MCAsmLayout &Layout,
-                         uint64_t StartAddress);
+  /// Compute the effective fragment size assuming it is layed out at the given
+  /// \arg SectionAddress and \arg FragmentOffset.
+  uint64_t ComputeFragmentSize(MCAsmLayout &Layout, const MCFragment &F,
+                               uint64_t SectionAddress,
+                               uint64_t FragmentOffset) const;
 
   /// LayoutOnce - Perform one layout iteration and return true if any offsets
   /// were adjusted.
@@ -671,18 +632,8 @@ private:
   void FinishLayout(MCAsmLayout &Layout);
 
 public:
-  /// Find the symbol which defines the atom containing given address, inside
-  /// the given section, or null if there is no such symbol.
-  //
-  // FIXME-PERF: Eliminate this, it is very slow.
-  const MCSymbolData *getAtomForAddress(const MCAsmLayout &Layout,
-                                        const MCSectionData *Section,
-                                        uint64_t Address) const;
-
   /// Find the symbol which defines the atom containing the given symbol, or
   /// null if there is no such symbol.
-  //
-  // FIXME-PERF: Eliminate this, it is very slow.
   const MCSymbolData *getAtom(const MCAsmLayout &Layout,
                               const MCSymbolData *Symbol) const;
 
diff --git a/include/llvm/MC/MCContext.h b/include/llvm/MC/MCContext.h
index 4434341..03b5fb0 100644
--- a/include/llvm/MC/MCContext.h
+++ b/include/llvm/MC/MCContext.h
@@ -20,6 +20,7 @@ namespace llvm {
   class MCExpr;
   class MCSection;
   class MCSymbol;
+  class MCLabel;
   class StringRef;
   class Twine;
   class MCSectionMachO;
@@ -43,6 +44,15 @@ namespace llvm {
     /// NextUniqueID - The next ID to dole out to an unnamed assembler temporary
     /// symbol.
     unsigned NextUniqueID;
+
+    /// Instances of directional local labels.
+    DenseMap<unsigned, MCLabel *> Instances;
+    /// NextInstance() creates the next instance of the directional local label
+    /// for the LocalLabelVal and adds it to the map if needed.
+    unsigned NextInstance(int64_t LocalLabelVal);
+    /// GetInstance() gets the current instance of the directional local label
+    /// for the LocalLabelVal and adds it to the map if needed.
+    unsigned GetInstance(int64_t LocalLabelVal);
     
     /// Allocator - Allocator object used for creating machine code objects.
     ///
@@ -50,7 +60,7 @@ namespace llvm {
     /// objects.
     BumpPtrAllocator Allocator;
     
-    void *MachOUniquingMap, *ELFUniquingMap;
+    void *MachOUniquingMap, *ELFUniquingMap, *COFFUniquingMap;
   public:
     explicit MCContext(const MCAsmInfo &MAI);
     ~MCContext();
@@ -64,6 +74,14 @@ namespace llvm {
     /// with a unique but unspecified name.
     MCSymbol *CreateTempSymbol();
 
+    /// CreateDirectionalLocalSymbol - Create the defintion of a directional
+    /// local symbol for numbered label (used for "1:" defintions).
+    MCSymbol *CreateDirectionalLocalSymbol(int64_t LocalLabelVal);
+
+    /// GetDirectionalLocalSymbol - Create and return a directional local
+    /// symbol for numbered label (used for "1b" or 1f" references).
+    MCSymbol *GetDirectionalLocalSymbol(int64_t LocalLabelVal, int bORf);
+
     /// GetOrCreateSymbol - Lookup the symbol inside with the specified
     /// @p Name.  If it exists, return it.  If not, create a forward
     /// reference and return it.
@@ -97,6 +115,15 @@ namespace llvm {
     const MCSection *getELFSection(StringRef Section, unsigned Type,
                                    unsigned Flags, SectionKind Kind,
                                    bool IsExplicit = false);
+
+    const MCSection *getCOFFSection(StringRef Section, unsigned Characteristics,
+                                    int Selection, SectionKind Kind);
+
+    const MCSection *getCOFFSection(StringRef Section, unsigned Characteristics,
+                                    SectionKind Kind) {
+      return getCOFFSection (Section, Characteristics, 0, Kind);
+    }
+
     
     /// @}
 
diff --git a/include/llvm/MC/MCExpr.h b/include/llvm/MC/MCExpr.h
index bd0684d..1f9b8f2 100644
--- a/include/llvm/MC/MCExpr.h
+++ b/include/llvm/MC/MCExpr.h
@@ -134,7 +134,10 @@ public:
     VK_NTPOFF,
     VK_PLT,
     VK_TLSGD,
-    VK_TPOFF
+    VK_TPOFF,
+    VK_ARM_HI16, // The R_ARM_MOVT_ABS relocation (:upper16: in the asm file)
+    VK_ARM_LO16, // The R_ARM_MOVW_ABS_NC relocation (:lower16: in the asm file)
+    VK_TLVP // Mach-O thread local variable relocation
   };
 
 private:
diff --git a/include/llvm/MC/MCFixup.h b/include/llvm/MC/MCFixup.h
index cd0dd19..eed4c34 100644
--- a/include/llvm/MC/MCFixup.h
+++ b/include/llvm/MC/MCFixup.h
@@ -10,26 +10,12 @@
 #ifndef LLVM_MC_MCFIXUP_H
 #define LLVM_MC_MCFIXUP_H
 
+#include "llvm/System/DataTypes.h"
 #include <cassert>
 
 namespace llvm {
 class MCExpr;
 
-// Private constants, do not use.
-//
-// This is currently laid out so that the MCFixup fields can be efficiently
-// accessed, while keeping the offset field large enough that the assembler
-// backend can reasonably use the MCFixup representation for an entire fragment
-// (splitting any overly large fragments).
-//
-// The division of bits between the kind and the opindex can be tweaked if we
-// end up needing more bits for target dependent kinds.
-enum {
-  MCFIXUP_NUM_GENERIC_KINDS = 128,
-  MCFIXUP_NUM_KIND_BITS = 16,
-  MCFIXUP_NUM_OFFSET_BITS = (32 - MCFIXUP_NUM_KIND_BITS)
-};
-
 /// MCFixupKind - Extensible enumeration to represent the type of a fixup.
 enum MCFixupKind {
   FK_Data_1 = 0, ///< A one-byte fixup.
@@ -37,12 +23,14 @@ enum MCFixupKind {
   FK_Data_4,     ///< A four-byte fixup.
   FK_Data_8,     ///< A eight-byte fixup.
 
-  FirstTargetFixupKind = MCFIXUP_NUM_GENERIC_KINDS,
+  FirstTargetFixupKind = 128,
 
-  MaxTargetFixupKind = (1 << MCFIXUP_NUM_KIND_BITS)
+  // Limit range of target fixups, in case we want to pack more efficiently
+  // later.
+  MaxTargetFixupKind = (1 << 8)
 };
 
-/// MCFixup - Encode information on a single operation to perform on an byte
+/// MCFixup - Encode information on a single operation to perform on a byte
 /// sequence (e.g., an encoded instruction) which requires assemble- or run-
 /// time patching.
 ///
@@ -57,36 +45,33 @@ enum MCFixupKind {
 /// fixups become relocations in the object file (or errors, if the fixup cannot
 /// be encoded on the target).
 class MCFixup {
-  static const unsigned MaxOffset = 1 << MCFIXUP_NUM_KIND_BITS;
-
   /// The value to put into the fixup location. The exact interpretation of the
-  /// expression is target dependent, usually it will one of the operands to an
-  /// instruction or an assembler directive.
+  /// expression is target dependent, usually it will be one of the operands to
+  /// an instruction or an assembler directive.
   const MCExpr *Value;
 
   /// The byte index of start of the relocation inside the encoded instruction.
-  unsigned Offset : MCFIXUP_NUM_OFFSET_BITS;
+  uint32_t Offset;
 
   /// The target dependent kind of fixup item this is. The kind is used to
   /// determine how the operand value should be encoded into the instruction.
-  unsigned Kind : MCFIXUP_NUM_KIND_BITS;
+  unsigned Kind;
 
 public:
-  static MCFixup Create(unsigned Offset, const MCExpr *Value,
+  static MCFixup Create(uint32_t Offset, const MCExpr *Value,
                         MCFixupKind Kind) {
+    assert(unsigned(Kind) < MaxTargetFixupKind && "Kind out of range!");
     MCFixup FI;
     FI.Value = Value;
     FI.Offset = Offset;
     FI.Kind = unsigned(Kind);
-
-    assert(Offset == FI.getOffset() && "Offset out of range!");
-    assert(Kind == FI.getKind() && "Kind out of range!");
     return FI;
   }
 
   MCFixupKind getKind() const { return MCFixupKind(Kind); }
 
-  unsigned getOffset() const { return Offset; }
+  uint32_t getOffset() const { return Offset; }
+  void setOffset(uint32_t Value) { Offset = Value; }
 
   const MCExpr *getValue() const { return Value; }
 
diff --git a/include/llvm/MC/MCLabel.h b/include/llvm/MC/MCLabel.h
new file mode 100644
index 0000000..727520d
--- /dev/null
+++ b/include/llvm/MC/MCLabel.h
@@ -0,0 +1,56 @@
+//===- MCLabel.h - Machine Code Directional Local Labels --------*- 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 the declaration of the MCLabel class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_MCLABEL_H
+#define LLVM_MC_MCLABEL_H
+
+namespace llvm {
+  class MCContext;
+  class raw_ostream;
+
+  /// MCLabel - Instances of this class represent a label name in the MC file,
+  /// and MCLabel are created and unique'd by the MCContext class.  MCLabel
+  /// should only be constructed for valid instances in the object file.
+  class MCLabel {
+    // Instance - the instance number of this Directional Local Label
+    unsigned Instance;
+
+  private:  // MCContext creates and uniques these.
+    friend class MCContext;
+    MCLabel(unsigned instance)
+      : Instance(instance) {}
+
+    MCLabel(const MCLabel&);       // DO NOT IMPLEMENT
+    void operator=(const MCLabel&); // DO NOT IMPLEMENT
+  public:
+    /// getInstance - Get the current instance of this Directional Local Label.
+    unsigned getInstance() const { return Instance; }
+
+    /// incInstance - Increment the current instance of this Directional Local
+    /// Label.
+    unsigned incInstance() { return ++Instance; }
+
+    /// print - Print the value to the stream \arg OS.
+    void print(raw_ostream &OS) const;
+
+    /// dump - Print the value to stderr.
+    void dump() const;
+  };
+
+  inline raw_ostream &operator<<(raw_ostream &OS, const MCLabel &Label) {
+    Label.print(OS);
+    return OS;
+  }
+} // end namespace llvm
+
+#endif
diff --git a/include/llvm/MC/MCMachOSymbolFlags.h b/include/llvm/MC/MCMachOSymbolFlags.h
new file mode 100644
index 0000000..c938c81
--- /dev/null
+++ b/include/llvm/MC/MCMachOSymbolFlags.h
@@ -0,0 +1,44 @@
+//===- MCMachOSymbolFlags.h - MachO Symbol Flags ----------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares the SymbolFlags used for the MachO target.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_MCMACHOSYMBOLFLAGS_H
+#define LLVM_MC_MCMACHOSYMBOLFLAGS_H
+
+// These flags are mostly used in MCMachOStreamer.cpp but also needed in
+// MachObjectWriter.cpp to test for Weak Definitions of symbols to emit
+// the correct relocation information.
+
+namespace llvm {
+  /// SymbolFlags - We store the value for the 'desc' symbol field in the lowest
+  /// 16 bits of the implementation defined flags.
+  enum SymbolFlags { // See <mach-o/nlist.h>.
+    SF_DescFlagsMask                        = 0xFFFF,
+
+    // Reference type flags.
+    SF_ReferenceTypeMask                    = 0x0007,
+    SF_ReferenceTypeUndefinedNonLazy        = 0x0000,
+    SF_ReferenceTypeUndefinedLazy           = 0x0001,
+    SF_ReferenceTypeDefined                 = 0x0002,
+    SF_ReferenceTypePrivateDefined          = 0x0003,
+    SF_ReferenceTypePrivateUndefinedNonLazy = 0x0004,
+    SF_ReferenceTypePrivateUndefinedLazy    = 0x0005,
+
+    // Other 'desc' flags.
+    SF_NoDeadStrip                          = 0x0020,
+    SF_WeakReference                        = 0x0040,
+    SF_WeakDefinition                       = 0x0080
+  };
+
+} // end namespace llvm
+
+#endif
diff --git a/include/llvm/MC/MCObjectWriter.h b/include/llvm/MC/MCObjectWriter.h
index 522ee77..e900584 100644
--- a/include/llvm/MC/MCObjectWriter.h
+++ b/include/llvm/MC/MCObjectWriter.h
@@ -15,9 +15,9 @@
 #include <cassert>
 
 namespace llvm {
-class MCAsmFixup;
 class MCAsmLayout;
 class MCAssembler;
+class MCFixup;
 class MCFragment;
 class MCValue;
 class raw_ostream;
@@ -72,13 +72,13 @@ public:
   virtual void RecordRelocation(const MCAssembler &Asm,
                                 const MCAsmLayout &Layout,
                                 const MCFragment *Fragment,
-                                const MCAsmFixup &Fixup, MCValue Target,
+                                const MCFixup &Fixup, MCValue Target,
                                 uint64_t &FixedValue) = 0;
 
   /// Write the object file.
   ///
   /// This routine is called by the assembler after layout and relaxation is
-  /// complete, fixups have been evaluate and applied, and relocations
+  /// complete, fixups have been evaluated and applied, and relocations
   /// generated.
   virtual void WriteObject(const MCAssembler &Asm,
                            const MCAsmLayout &Layout) = 0;
@@ -152,6 +152,8 @@ public:
   }
 
   void WriteBytes(StringRef Str, unsigned ZeroFillSize = 0) {
+    assert((ZeroFillSize == 0 || Str.size () <= ZeroFillSize) &&
+      "data size greater than fill size, unexpected large write will occur");
     OS << Str;
     if (ZeroFillSize)
       WriteZeros(ZeroFillSize - Str.size());
diff --git a/include/llvm/MC/MCParser/AsmParser.h b/include/llvm/MC/MCParser/AsmParser.h
index 7a78906..e929fd1 100644
--- a/include/llvm/MC/MCParser/AsmParser.h
+++ b/include/llvm/MC/MCParser/AsmParser.h
@@ -131,11 +131,13 @@ private:
   /// ParseDirectiveSymbolAttribute - Parse a directive like ".globl" which
   /// accepts a single symbol (which should be a label or an external).
   bool ParseDirectiveSymbolAttribute(MCSymbolAttr Attr);
+  bool ParseDirectiveELFType(); // ELF specific ".type"
   bool ParseDirectiveDarwinSymbolDesc(); // Darwin specific ".desc"
   bool ParseDirectiveDarwinLsym(); // Darwin specific ".lsym"
 
   bool ParseDirectiveComm(bool IsLocal); // ".comm" and ".lcomm"
   bool ParseDirectiveDarwinZerofill(); // Darwin specific ".zerofill"
+  bool ParseDirectiveDarwinTBSS(); // Darwin specific ".tbss"
 
   // Darwin specific ".subsections_via_symbols"
   bool ParseDirectiveDarwinSubsectionsViaSymbols();
diff --git a/include/llvm/MC/MCParser/MCAsmLexer.h b/include/llvm/MC/MCParser/MCAsmLexer.h
index 075b69b..bd1496f 100644
--- a/include/llvm/MC/MCParser/MCAsmLexer.h
+++ b/include/llvm/MC/MCParser/MCAsmLexer.h
@@ -47,7 +47,7 @@ public:
     Pipe, PipePipe, Caret, 
     Amp, AmpAmp, Exclaim, ExclaimEqual, Percent, Hash,
     Less, LessEqual, LessLess, LessGreater,
-    Greater, GreaterEqual, GreaterGreater
+    Greater, GreaterEqual, GreaterGreater, At
   };
 
   TokenKind Kind;
diff --git a/include/llvm/MC/MCSection.h b/include/llvm/MC/MCSection.h
index e9c19fc..808767c 100644
--- a/include/llvm/MC/MCSection.h
+++ b/include/llvm/MC/MCSection.h
@@ -17,6 +17,7 @@
 #include <string>
 #include "llvm/ADT/StringRef.h"
 #include "llvm/MC/SectionKind.h"
+#include "llvm/Support/Casting.h"
 
 namespace llvm {
   class MCContext;
@@ -27,15 +28,27 @@ namespace llvm {
   /// section in the current translation unit.  The MCContext class uniques and
   /// creates these.
   class MCSection {
+  public:
+    enum SectionVariant {
+      SV_COFF = 0,
+      SV_ELF,
+      SV_MachO,
+      SV_PIC16
+    };
+
+  private:
     MCSection(const MCSection&);      // DO NOT IMPLEMENT
     void operator=(const MCSection&); // DO NOT IMPLEMENT
   protected:
-    MCSection(SectionKind K) : Kind(K) {}
+    MCSection(SectionVariant V, SectionKind K) : Variant(V), Kind(K) {}
+    SectionVariant Variant;
     SectionKind Kind;
   public:
     virtual ~MCSection();
 
     SectionKind getKind() const { return Kind; }
+
+    SectionVariant getVariant() const { return Variant; }
     
     virtual void PrintSwitchToSection(const MCAsmInfo &MAI,
                                       raw_ostream &OS) const = 0;
@@ -47,32 +60,8 @@ namespace llvm {
     virtual bool isBaseAddressKnownZero() const {
       return false;
     }
-  };
-
-  class MCSectionCOFF : public MCSection {
-    // The memory for this string is stored in the same MCContext as *this.
-    StringRef Name;
-    
-    /// IsDirective - This is true if the section name is a directive, not
-    /// something that should be printed with ".section".
-    ///
-    /// FIXME: This is a hack.  Switch to a semantic view of the section instead
-    /// of a syntactic one.
-    bool IsDirective;
-    
-    MCSectionCOFF(StringRef name, bool isDirective, SectionKind K)
-      : MCSection(K), Name(name), IsDirective(isDirective) {
-    }
-  public:
-    
-    static MCSectionCOFF *Create(StringRef Name, bool IsDirective, 
-                                 SectionKind K, MCContext &Ctx);
 
-    StringRef getName() const { return Name; }
-    bool isDirective() const { return IsDirective; }
-    
-    virtual void PrintSwitchToSection(const MCAsmInfo &MAI,
-                                      raw_ostream &OS) const;
+    static bool classof(const MCSection *) { return true; }
   };
   
 } // end namespace llvm
diff --git a/include/llvm/MC/MCSectionCOFF.h b/include/llvm/MC/MCSectionCOFF.h
new file mode 100644
index 0000000..938a388
--- /dev/null
+++ b/include/llvm/MC/MCSectionCOFF.h
@@ -0,0 +1,115 @@
+//===- MCSectionCOFF.h - COFF Machine Code Sections -------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares the MCSectionCOFF class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_MCSECTIONCOFF_H
+#define LLVM_MC_MCSECTIONCOFF_H
+
+#include "llvm/MC/MCSection.h"
+
+namespace llvm {
+  
+/// MCSectionCOFF - This represents a section on Windows
+  class MCSectionCOFF : public MCSection {
+    // The memory for this string is stored in the same MCContext as *this.
+    StringRef SectionName;
+    
+    /// Characteristics - This is the Characteristics field of a section,
+    //  drawn from the enums below.
+    unsigned Characteristics;
+
+    /// Selection - This is the Selection field for the section symbol, if
+    /// it is a COMDAT section (Characteristics & IMAGE_SCN_LNK_COMDAT) != 0
+    int Selection;
+
+  private:
+    friend class MCContext;
+    MCSectionCOFF(StringRef Section, unsigned Characteristics,
+                  int Selection, SectionKind K)
+      : MCSection(SV_COFF, K), SectionName(Section),
+        Characteristics(Characteristics), Selection (Selection) {
+      assert ((Characteristics & 0x00F00000) == 0 &&
+        "alignment must not be set upon section creation");
+    }
+    ~MCSectionCOFF();
+
+  public:
+    /// ShouldOmitSectionDirective - Decides whether a '.section' directive
+    /// should be printed before the section name
+    bool ShouldOmitSectionDirective(StringRef Name, const MCAsmInfo &MAI) const;
+
+    //FIXME: all COFF enumerations/flags should be standardized into one place...
+    // Target/X86COFF.h doesn't seem right as COFF can be used for other targets,
+    // MC/WinCOFF.h maybe right as it isn't target or entity specific, and it is
+    //   pretty low on the dependancy graph (is there any need to support non
+    //   windows COFF?)
+    // here is good for section stuff, but others should go elsewhere
+
+    /// Valid section flags.
+    enum {
+      IMAGE_SCN_TYPE_NO_PAD                     = 0x00000008,
+      IMAGE_SCN_CNT_CODE                        = 0x00000020,
+      IMAGE_SCN_CNT_INITIALIZED_DATA            = 0x00000040,
+      IMAGE_SCN_CNT_UNINITIALIZED_DATA          = 0x00000080,
+      IMAGE_SCN_LNK_OTHER                       = 0x00000100,
+      IMAGE_SCN_LNK_INFO                        = 0x00000200,
+      IMAGE_SCN_LNK_REMOVE                      = 0x00000800,
+      IMAGE_SCN_LNK_COMDAT                      = 0x00001000,
+      IMAGE_SCN_MEM_FARDATA                     = 0x00008000,
+      IMAGE_SCN_MEM_PURGEABLE                   = 0x00020000,
+      IMAGE_SCN_MEM_16BIT                       = 0x00020000,
+      IMAGE_SCN_MEM_LOCKED                      = 0x00040000,
+      IMAGE_SCN_MEM_PRELOAD                     = 0x00080000,
+      /* these are handled elsewhere
+      IMAGE_SCN_ALIGN_1BYTES                    = 0x00100000,
+      IMAGE_SCN_ALIGN_2BYTES                    = 0x00200000,
+      IMAGE_SCN_ALIGN_4BYTES                    = 0x00300000,
+      IMAGE_SCN_ALIGN_8BYTES                    = 0x00400000,
+      IMAGE_SCN_ALIGN_16BYTES                   = 0x00500000,
+      IMAGE_SCN_ALIGN_32BYTES                   = 0x00600000,
+      IMAGE_SCN_ALIGN_64BYTES                   = 0x00700000,
+      */
+      IMAGE_SCN_LNK_NRELOC_OVFL                 = 0x01000000,
+      IMAGE_SCN_MEM_DISCARDABLE                 = 0x02000000,
+      IMAGE_SCN_MEM_NOT_CACHED                  = 0x04000000,
+      IMAGE_SCN_MEM_NOT_PAGED                   = 0x08000000,
+      IMAGE_SCN_MEM_SHARED                      = 0x10000000,
+      IMAGE_SCN_MEM_EXECUTE                     = 0x20000000,
+      IMAGE_SCN_MEM_READ                        = 0x40000000,
+      IMAGE_SCN_MEM_WRITE                       = 0x80000000
+    };
+
+    enum {
+      IMAGE_COMDAT_SELECT_NODUPLICATES = 1,
+      IMAGE_COMDAT_SELECT_ANY,
+      IMAGE_COMDAT_SELECT_SAME_SIZE,
+      IMAGE_COMDAT_SELECT_EXACT_MATCH,
+      IMAGE_COMDAT_SELECT_ASSOCIATIVE,
+      IMAGE_COMDAT_SELECT_LARGEST
+    };
+
+    StringRef getSectionName() const { return SectionName; }
+    unsigned getCharacteristics() const { return Characteristics; }
+    int getSelection () const { return Selection; }
+    
+    virtual void PrintSwitchToSection(const MCAsmInfo &MAI,
+                                      raw_ostream &OS) const;
+
+    static bool classof(const MCSection *S) {
+      return S->getVariant() == SV_COFF;
+    }
+    static bool classof(const MCSectionCOFF *) { return true; }
+  };
+
+} // end namespace llvm
+
+#endif
diff --git a/include/llvm/MC/MCSectionELF.h b/include/llvm/MC/MCSectionELF.h
index 7054668..5fe8171 100644
--- a/include/llvm/MC/MCSectionELF.h
+++ b/include/llvm/MC/MCSectionELF.h
@@ -40,7 +40,7 @@ private:
   friend class MCContext;
   MCSectionELF(StringRef Section, unsigned type, unsigned flags,
                SectionKind K, bool isExplicit)
-    : MCSection(K), SectionName(Section), Type(type), Flags(flags), 
+    : MCSection(SV_ELF, K), SectionName(Section), Type(type), Flags(flags),
       IsExplicit(isExplicit) {}
   ~MCSectionELF();
 public:
@@ -178,6 +178,11 @@ public:
   virtual bool isBaseAddressKnownZero() const {
     return (getFlags() & SHF_ALLOC) == 0;
   }
+
+  static bool classof(const MCSection *S) {
+    return S->getVariant() == SV_ELF;
+  }
+  static bool classof(const MCSectionELF *) { return true; }
 };
 
 } // end namespace llvm
diff --git a/include/llvm/MC/MCSectionMachO.h b/include/llvm/MC/MCSectionMachO.h
index f3bc8ed..2d9d133 100644
--- a/include/llvm/MC/MCSectionMachO.h
+++ b/include/llvm/MC/MCSectionMachO.h
@@ -87,8 +87,20 @@ public:
     /// S_LAZY_DYLIB_SYMBOL_POINTERS - Section with lazy symbol pointers to
     /// lazy loaded dylibs.
     S_LAZY_DYLIB_SYMBOL_POINTERS = 0x10U,
+    /// S_THREAD_LOCAL_REGULAR - Section with ....
+    S_THREAD_LOCAL_REGULAR = 0x11U,
+    /// S_THREAD_LOCAL_ZEROFILL - Thread local zerofill section.
+    S_THREAD_LOCAL_ZEROFILL = 0x12U,
+    /// S_THREAD_LOCAL_VARIABLES - Section with thread local variable structure
+    /// data.
+    S_THREAD_LOCAL_VARIABLES = 0x13U,
+    /// S_THREAD_LOCAL_VARIABLE_POINTERS - Section with ....
+    S_THREAD_LOCAL_VARIABLE_POINTERS = 0x14U,
+    /// S_THREAD_LOCAL_INIT_FUNCTION_POINTERS - Section with thread local
+    /// variable initialization pointers to functions.
+    S_THREAD_LOCAL_INIT_FUNCTION_POINTERS = 0x15U,
 
-    LAST_KNOWN_SECTION_TYPE = S_LAZY_DYLIB_SYMBOL_POINTERS,
+    LAST_KNOWN_SECTION_TYPE = S_THREAD_LOCAL_INIT_FUNCTION_POINTERS,
     
 
     // Valid section attributes.
@@ -136,6 +148,9 @@ public:
   unsigned getStubSize() const { return Reserved2; }
 
   unsigned getType() const { return TypeAndAttributes & SECTION_TYPE; }
+  bool hasAttribute(unsigned Value) const {
+    return (TypeAndAttributes & Value) != 0;
+  }
 
   /// ParseSectionSpecifier - Parse the section specifier indicated by "Spec".
   /// This is a string that can appear after a .section directive in a mach-o
@@ -150,6 +165,11 @@ public:
 
   virtual void PrintSwitchToSection(const MCAsmInfo &MAI,
                                     raw_ostream &OS) const;
+
+  static bool classof(const MCSection *S) {
+    return S->getVariant() == SV_MachO;
+  }
+  static bool classof(const MCSectionMachO *) { return true; }
 };
 
 } // end namespace llvm
diff --git a/include/llvm/MC/MCStreamer.h b/include/llvm/MC/MCStreamer.h
index 4667c41..0783159 100644
--- a/include/llvm/MC/MCStreamer.h
+++ b/include/llvm/MC/MCStreamer.h
@@ -27,7 +27,7 @@ namespace llvm {
   class MCSection;
   class MCSymbol;
   class StringRef;
-class TargetAsmBackend;
+  class TargetAsmBackend;
   class Twine;
   class raw_ostream;
   class formatted_raw_ostream;
@@ -138,7 +138,24 @@ class TargetAsmBackend;
     /// @param DescValue - The value to set into the n_desc field.
     virtual void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) = 0;
 
-    
+    /// BeginCOFFSymbolDef - Start emitting COFF symbol definition
+    ///
+    /// @param Symbol - The symbol to have its External & Type fields set.
+    virtual void BeginCOFFSymbolDef(const MCSymbol *Symbol) = 0;
+
+    /// EmitCOFFSymbolStorageClass - Emit the storage class of the symbol.
+    ///
+    /// @param StorageClass - The storage class the symbol should have.
+    virtual void EmitCOFFSymbolStorageClass(int StorageClass) = 0;
+
+    /// EmitCOFFSymbolType - Emit the type of the symbol.
+    ///
+    /// @param Type - A COFF type identifier (see COFF::SymbolType in X86COFF.h)
+    virtual void EmitCOFFSymbolType(int Type) = 0;
+
+    /// EndCOFFSymbolDef - Marks the end of the symbol definition.
+    virtual void EndCOFFSymbolDef() = 0;
+
     /// EmitELFSize - Emit an ELF .size directive.
     ///
     /// This corresponds to an assembler statement such as:
@@ -161,7 +178,7 @@ class TargetAsmBackend;
     /// @param Size - The size of the common symbol.
     virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size) = 0;
     
-    /// EmitZerofill - Emit a the zerofill section and an option symbol.
+    /// EmitZerofill - Emit the zerofill section and an optional symbol.
     ///
     /// @param Section - The zerofill section to create and or to put the symbol
     /// @param Symbol - The zerofill symbol to emit, if non-NULL.
@@ -171,6 +188,15 @@ class TargetAsmBackend;
     virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol = 0,
                               unsigned Size = 0,unsigned ByteAlignment = 0) = 0;
 
+    /// EmitTBSSSymbol - Emit a thread local bss (.tbss) symbol.
+    ///
+    /// @param Section - The thread local common section.
+    /// @param Symbol - The thread local common symbol to emit.
+    /// @param Size - The size of the symbol.
+    /// @param ByteAlignment - The alignment of the thread local common symbol
+    /// if non-zero.  This must be a power of 2 on some targets.
+    virtual void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
+                                uint64_t Size, unsigned ByteAlignment = 0) = 0;                                
     /// @}
     /// @name Generating Data
     /// @{
@@ -315,12 +341,18 @@ class TargetAsmBackend;
                                 MCCodeEmitter *CE = 0,
                                 bool ShowInst = false);
 
-  /// createMachOStream - Create a machine code streamer which will generative
+  /// createMachOStreamer - Create a machine code streamer which will generative
   /// Mach-O format object files.
   MCStreamer *createMachOStreamer(MCContext &Ctx, TargetAsmBackend &TAB,
                                   raw_ostream &OS, MCCodeEmitter *CE,
                                   bool RelaxAll = false);
 
+  /// createLoggingStreamer - Create a machine code streamer which just logs the
+  /// API calls and then dispatches to another streamer.
+  ///
+  /// The new streamer takes ownership of the \arg Child.
+  MCStreamer *createLoggingStreamer(MCStreamer *Child, raw_ostream &OS);
+
 } // end namespace llvm
 
 #endif
diff --git a/include/llvm/MC/MCSymbol.h b/include/llvm/MC/MCSymbol.h
index fb96506..1b432c2 100644
--- a/include/llvm/MC/MCSymbol.h
+++ b/include/llvm/MC/MCSymbol.h
@@ -52,10 +52,15 @@ namespace llvm {
     /// "Lfoo" or ".foo".
     unsigned IsTemporary : 1;
 
+    /// IsUsedInExpr - True if this symbol has been used in an expression and
+    /// cannot be redefined.
+    unsigned IsUsedInExpr : 1;
+
   private:  // MCContext creates and uniques these.
     friend class MCContext;
     MCSymbol(StringRef name, bool isTemporary)
-      : Name(name), Section(0), Value(0), IsTemporary(isTemporary) {}
+      : Name(name), Section(0), Value(0),
+        IsTemporary(isTemporary), IsUsedInExpr(false) {}
 
     MCSymbol(const MCSymbol&);       // DO NOT IMPLEMENT
     void operator=(const MCSymbol&); // DO NOT IMPLEMENT
@@ -63,13 +68,15 @@ namespace llvm {
     /// getName - Get the symbol name.
     StringRef getName() const { return Name; }
 
-    /// @name Symbol Type
+    /// @name Accessors
     /// @{
 
     /// isTemporary - Check if this is an assembler temporary symbol.
-    bool isTemporary() const {
-      return IsTemporary;
-    }
+    bool isTemporary() const { return IsTemporary; }
+
+    /// isUsedInExpr - Check if this is an assembler temporary symbol.
+    bool isUsedInExpr() const { return IsUsedInExpr; }
+    void setUsedInExpr(bool Value) { IsUsedInExpr = Value; }
 
     /// @}
     /// @name Associated Sections
@@ -125,14 +132,14 @@ namespace llvm {
       return Value != 0;
     }
 
-    /// getValue() - Get the value for variable symbols, or null if the symbol
-    /// is not a variable.
-    const MCExpr *getValue() const { return Value; }
-
-    void setValue(const MCExpr *Value) {
-      this->Value = Value;
+    /// getValue() - Get the value for variable symbols.
+    const MCExpr *getVariableValue() const {
+      assert(isVariable() && "Invalid accessor!");
+      return Value;
     }
 
+    void setVariableValue(const MCExpr *Value);
+
     /// @}
 
     /// print - Print the value to the stream \arg OS.
diff --git a/include/llvm/MC/MachObjectWriter.h b/include/llvm/MC/MachObjectWriter.h
index 844025d..9b1ff1d 100644
--- a/include/llvm/MC/MachObjectWriter.h
+++ b/include/llvm/MC/MachObjectWriter.h
@@ -15,9 +15,9 @@
 #include <cassert>
 
 namespace llvm {
-class MCAsmFixup;
 class MCAssembler;
 class MCFragment;
+class MCFixup;
 class MCValue;
 class raw_ostream;
 
@@ -33,7 +33,7 @@ public:
   virtual void RecordRelocation(const MCAssembler &Asm,
                                 const MCAsmLayout &Layout,
                                 const MCFragment *Fragment,
-                                const MCAsmFixup &Fixup, MCValue Target,
+                                const MCFixup &Fixup, MCValue Target,
                                 uint64_t &FixedValue);
 
   virtual void WriteObject(const MCAssembler &Asm, const MCAsmLayout &Layout);