libbcc

Change-Id: Ieaa3ebd5a38f370752495549f8870b534eeedfc5

11 files changed, 478 insertions, 104 deletions

diff --git a/lib/MC/Android.mk b/lib/MC/Android.mk
new file mode 100644
index 0000000..dac5a54
--- /dev/null
+++ b/lib/MC/Android.mk
@@ -0,0 +1,45 @@
+LOCAL_PATH:= $(call my-dir)
+
+mc_SRC_FILES :=	\
+	MCAsmInfo.cpp	\
+	MCAsmInfoCOFF.cpp	\
+	MCAsmInfoDarwin.cpp	\
+	MCAsmStreamer.cpp	\
+	MCAssembler.cpp	\
+	MCCodeEmitter.cpp	\
+	MCContext.cpp	\
+	MCDisassembler.cpp	\
+	MCExpr.cpp	\
+	MCInst.cpp	\
+	MCInstPrinter.cpp	\
+	MCMachOStreamer.cpp	\
+	MCNullStreamer.cpp	\
+	MCSection.cpp	\
+	MCSectionELF.cpp	\
+	MCSectionMachO.cpp	\
+	MCStreamer.cpp	\
+	MCSymbol.cpp	\
+	MCValue.cpp	\
+	TargetAsmBackend.cpp
+
+# For the host
+# =====================================================
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := $(mc_SRC_FILES)
+
+LOCAL_MODULE:= libLLVMMC
+
+include $(LLVM_HOST_BUILD_MK)
+include $(BUILD_HOST_STATIC_LIBRARY)
+
+# For the device
+# =====================================================
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := $(mc_SRC_FILES)
+
+LOCAL_MODULE:= libLLVMMC
+
+include $(LLVM_DEVICE_BUILD_MK)
+include $(BUILD_STATIC_LIBRARY)
diff --git a/lib/MC/CMakeLists.txt b/lib/MC/CMakeLists.txt
index 9ead33b..4cf71dc 100644
--- a/lib/MC/CMakeLists.txt
+++ b/lib/MC/CMakeLists.txt
@@ -18,4 +18,5 @@ add_llvm_library(LLVMMC
   MCStreamer.cpp
   MCSymbol.cpp
   MCValue.cpp
+  TargetAsmBackend.cpp
   )
diff --git a/lib/MC/MCAsmStreamer.cpp b/lib/MC/MCAsmStreamer.cpp
index 828377f..1b66900 100644
--- a/lib/MC/MCAsmStreamer.cpp
+++ b/lib/MC/MCAsmStreamer.cpp
@@ -22,6 +22,7 @@
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/Format.h"
 #include "llvm/Support/FormattedStream.h"
+#include <ctype.h>
 using namespace llvm;
 
 namespace {
@@ -134,6 +135,9 @@ public:
                                     unsigned ValueSize = 1,
                                     unsigned MaxBytesToEmit = 0);
 
+  virtual void EmitCodeAlignment(unsigned ByteAlignment,
+                                 unsigned MaxBytesToEmit = 0);
+
   virtual void EmitValueToOffset(const MCExpr *Offset,
                                  unsigned char Value = 0);
 
@@ -513,6 +517,13 @@ void MCAsmStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
   EmitEOL();
 }
 
+void MCAsmStreamer::EmitCodeAlignment(unsigned ByteAlignment,
+                                      unsigned MaxBytesToEmit) {
+  // Emit with a text fill value.
+  EmitValueToAlignment(ByteAlignment, MAI.getTextAlignFillValue(),
+                       1, MaxBytesToEmit);
+}
+
 void MCAsmStreamer::EmitValueToOffset(const MCExpr *Offset,
                                       unsigned char Value) {
   // FIXME: Verify that Offset is associated with the current section.
@@ -552,7 +563,7 @@ void MCAsmStreamer::AddEncodingComment(const MCInst &Inst) {
 
   for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
     MCFixup &F = Fixups[i];
-    MCFixupKindInfo &Info = Emitter->getFixupKindInfo(F.getKind());
+    const MCFixupKindInfo &Info = Emitter->getFixupKindInfo(F.getKind());
     for (unsigned j = 0; j != Info.TargetSize; ++j) {
       unsigned Index = F.getOffset() * 8 + Info.TargetOffset + j;
       assert(Index < Code.size() * 8 && "Invalid offset in fixup!");
@@ -599,7 +610,7 @@ void MCAsmStreamer::AddEncodingComment(const MCInst &Inst) {
 
   for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
     MCFixup &F = Fixups[i];
-    MCFixupKindInfo &Info = Emitter->getFixupKindInfo(F.getKind());
+    const MCFixupKindInfo &Info = Emitter->getFixupKindInfo(F.getKind());
     OS << "  fixup " << char('A' + i) << " - " << "offset: " << F.getOffset()
        << ", value: " << *F.getValue() << ", kind: " << Info.Name << "\n";
   }
@@ -617,6 +628,12 @@ void MCAsmStreamer::EmitInstruction(const MCInst &Inst) {
     raw_ostream &OS = GetCommentOS();
     OS << "<MCInst #" << Inst.getOpcode();
     
+    StringRef InstName;
+    if (InstPrinter)
+      InstName = InstPrinter->getOpcodeName(Inst.getOpcode());
+    if (!InstName.empty())
+      OS << ' ' << InstName;
+    
     for (unsigned i = 0, e = Inst.getNumOperands(); i != e; ++i) {
       OS << "\n  ";
       Inst.getOperand(i).print(OS, &MAI);
diff --git a/lib/MC/MCAssembler.cpp b/lib/MC/MCAssembler.cpp
index bdc886b..96227db 100644
--- a/lib/MC/MCAssembler.cpp
+++ b/lib/MC/MCAssembler.cpp
@@ -16,11 +16,17 @@
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/Statistic.h"
+#include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/MachO.h"
 #include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/Debug.h"
+
+// FIXME: Gross.
+#include "../Target/X86/X86FixupKinds.h"
+
 #include <vector>
 using namespace llvm;
 
@@ -36,6 +42,8 @@ STATISTIC(EmittedFragments, "Number of emitted assembler fragments");
 static void WriteFileData(raw_ostream &OS, const MCSectionData &SD,
                           MachObjectWriter &MOW);
 
+static uint64_t WriteNopData(uint64_t Count, MachObjectWriter &MOW);
+
 /// isVirtualSection - Check if this is a section which does not actually exist
 /// in the object file.
 static bool isVirtualSection(const MCSection &Section) {
@@ -45,6 +53,30 @@ static bool isVirtualSection(const MCSection &Section) {
   return (Type == MCSectionMachO::S_ZEROFILL);
 }
 
+static unsigned getFixupKindLog2Size(unsigned Kind) {
+  switch (Kind) {
+  default: llvm_unreachable("invalid fixup kind!");
+  case X86::reloc_pcrel_1byte:
+  case FK_Data_1: return 0;
+  case FK_Data_2: return 1;
+  case X86::reloc_pcrel_4byte:
+  case X86::reloc_riprel_4byte:
+  case FK_Data_4: return 2;
+  case FK_Data_8: return 3;
+  }
+}
+
+static bool isFixupKindPCRel(unsigned Kind) {
+  switch (Kind) {
+  default:
+    return false;
+  case X86::reloc_pcrel_1byte:
+  case X86::reloc_pcrel_4byte:
+  case X86::reloc_riprel_4byte:
+    return true;
+  }
+}
+
 class MachObjectWriter {
   // See <mach-o/loader.h>.
   enum {
@@ -402,13 +434,14 @@ public:
     uint32_t Word0;
     uint32_t Word1;
   };
-  void ComputeScatteredRelocationInfo(MCAssembler &Asm,
-                                      MCSectionData::Fixup &Fixup,
+  void ComputeScatteredRelocationInfo(MCAssembler &Asm, MCFragment &Fragment,
+                                      MCAsmFixup &Fixup,
                                       const MCValue &Target,
                              DenseMap<const MCSymbol*,MCSymbolData*> &SymbolMap,
                                      std::vector<MachRelocationEntry> &Relocs) {
-    uint32_t Address = Fixup.Fragment->getOffset() + Fixup.Offset;
+    uint32_t Address = Fragment.getOffset() + Fixup.Offset;
     unsigned IsPCRel = 0;
+    unsigned Log2Size = getFixupKindLog2Size(Fixup.Kind);
     unsigned Type = RIT_Vanilla;
 
     // See <reloc.h>.
@@ -424,11 +457,12 @@ public:
       Value2 = SD->getFragment()->getAddress() + SD->getOffset();
     }
 
-    unsigned Log2Size = Log2_32(Fixup.Size);
-    assert((1U << Log2Size) == Fixup.Size && "Invalid fixup size!");
-
     // The value which goes in the fixup is current value of the expression.
     Fixup.FixedValue = Value - Value2 + Target.getConstant();
+    if (isFixupKindPCRel(Fixup.Kind)) {
+      Fixup.FixedValue -= Address;
+      IsPCRel = 1;
+    }
 
     MachRelocationEntry MRE;
     MRE.Word0 = ((Address   <<  0) |
@@ -453,8 +487,8 @@ public:
     }
   }
 
-  void ComputeRelocationInfo(MCAssembler &Asm,
-                             MCSectionData::Fixup &Fixup,
+  void ComputeRelocationInfo(MCAssembler &Asm, MCDataFragment &Fragment,
+                             MCAsmFixup &Fixup,
                              DenseMap<const MCSymbol*,MCSymbolData*> &SymbolMap,
                              std::vector<MachRelocationEntry> &Relocs) {
     MCValue Target;
@@ -466,19 +500,22 @@ public:
     if (Target.getSymB() ||
         (Target.getSymA() && !Target.getSymA()->isUndefined() &&
          Target.getConstant()))
-      return ComputeScatteredRelocationInfo(Asm, Fixup, Target,
+      return ComputeScatteredRelocationInfo(Asm, Fragment, Fixup, Target,
                                             SymbolMap, Relocs);
 
     // See <reloc.h>.
-    uint32_t Address = Fixup.Fragment->getOffset() + Fixup.Offset;
+    uint32_t Address = Fragment.getOffset() + Fixup.Offset;
     uint32_t Value = 0;
     unsigned Index = 0;
     unsigned IsPCRel = 0;
+    unsigned Log2Size = getFixupKindLog2Size(Fixup.Kind);
     unsigned IsExtern = 0;
     unsigned Type = 0;
 
     if (Target.isAbsolute()) { // constant
       // SymbolNum of 0 indicates the absolute section.
+      //
+      // FIXME: When is this generated?
       Type = RIT_Vanilla;
       Value = 0;
       llvm_unreachable("FIXME: Not yet implemented!");
@@ -495,10 +532,11 @@ public:
         //
         // FIXME: O(N)
         Index = 1;
-        for (MCAssembler::iterator it = Asm.begin(),
-               ie = Asm.end(); it != ie; ++it, ++Index)
+        MCAssembler::iterator it = Asm.begin(), ie = Asm.end();
+        for (; it != ie; ++it, ++Index)
           if (&*it == SD->getFragment()->getParent())
             break;
+        assert(it != ie && "Unable to find section index!");
         Value = SD->getFragment()->getAddress() + SD->getOffset();
       }
 
@@ -508,8 +546,10 @@ public:
     // The value which goes in the fixup is current value of the expression.
     Fixup.FixedValue = Value + Target.getConstant();
 
-    unsigned Log2Size = Log2_32(Fixup.Size);
-    assert((1U << Log2Size) == Fixup.Size && "Invalid fixup size!");
+    if (isFixupKindPCRel(Fixup.Kind)) {
+      Fixup.FixedValue -= Address;
+      IsPCRel = 1;
+    }
 
     // struct relocation_info (8 bytes)
     MachRelocationEntry MRE;
@@ -766,17 +806,20 @@ public:
     // is written.
     std::vector<MachRelocationEntry> RelocInfos;
     uint64_t RelocTableEnd = SectionDataStart + SectionDataFileSize;
-    for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie;
-         ++it) {
+    for (MCAssembler::iterator it = Asm.begin(),
+           ie = Asm.end(); it != ie; ++it) {
       MCSectionData &SD = *it;
 
       // The assembler writes relocations in the reverse order they were seen.
       //
       // FIXME: It is probably more complicated than this.
       unsigned NumRelocsStart = RelocInfos.size();
-      for (unsigned i = 0, e = SD.fixup_size(); i != e; ++i)
-        ComputeRelocationInfo(Asm, SD.getFixups()[e - i - 1], SymbolMap,
-                              RelocInfos);
+      for (MCSectionData::reverse_iterator it2 = SD.rbegin(),
+             ie2 = SD.rend(); it2 != ie2; ++it2)
+        if (MCDataFragment *DF = dyn_cast<MCDataFragment>(&*it2))
+          for (unsigned i = 0, e = DF->fixup_size(); i != e; ++i)
+            ComputeRelocationInfo(Asm, *DF, DF->getFixups()[e - i - 1],
+                                  SymbolMap, RelocInfos);
 
       unsigned NumRelocs = RelocInfos.size() - NumRelocsStart;
       uint64_t SectionStart = SectionDataStart + SD.getAddress();
@@ -871,6 +914,16 @@ public:
       OS << StringTable.str();
     }
   }
+
+  void ApplyFixup(const MCAsmFixup &Fixup, MCDataFragment &DF) {
+    unsigned Size = 1 << getFixupKindLog2Size(Fixup.Kind);
+
+    // FIXME: Endianness assumption.
+    assert(Fixup.Offset + Size <= DF.getContents().size() &&
+           "Invalid fixup offset!");
+    for (unsigned i = 0; i != Size; ++i)
+      DF.getContents()[Fixup.Offset + i] = uint8_t(Fixup.FixedValue >> (i * 8));
+  }
 };
 
 /* *** */
@@ -905,35 +958,12 @@ MCSectionData::MCSectionData(const MCSection &_Section, MCAssembler *A)
     Address(~UINT64_C(0)),
     Size(~UINT64_C(0)),
     FileSize(~UINT64_C(0)),
-    LastFixupLookup(~0),
     HasInstructions(false)
 {
   if (A)
     A->getSectionList().push_back(this);
 }
 
-const MCSectionData::Fixup *
-MCSectionData::LookupFixup(const MCFragment *Fragment, uint64_t Offset) const {
-  // Use a one level cache to turn the common case of accessing the fixups in
-  // order into O(1) instead of O(N).
-  unsigned i = LastFixupLookup, Count = Fixups.size(), End = Fixups.size();
-  if (i >= End)
-    i = 0;
-  while (Count--) {
-    const Fixup &F = Fixups[i];
-    if (F.Fragment == Fragment && F.Offset == Offset) {
-      LastFixupLookup = i;
-      return &F;
-    }
-
-    ++i;
-    if (i == End)
-      i = 0;
-  }
-
-  return 0;
-}
-
 /* *** */
 
 MCSymbolData::MCSymbolData() : Symbol(0) {}
@@ -980,31 +1010,10 @@ void MCAssembler::LayoutSection(MCSectionData &SD) {
     }
 
     case MCFragment::FT_Data:
+    case MCFragment::FT_Fill:
       F.setFileSize(F.getMaxFileSize());
       break;
 
-    case MCFragment::FT_Fill: {
-      MCFillFragment &FF = cast<MCFillFragment>(F);
-
-      F.setFileSize(F.getMaxFileSize());
-
-      MCValue Target;
-      if (!FF.getValue().EvaluateAsRelocatable(Target))
-        llvm_report_error("expected relocatable expression");
-
-      // If the fill value is constant, thats it.
-      if (Target.isAbsolute())
-        break;
-
-      // Otherwise, add fixups for the values.
-      for (uint64_t i = 0, e = FF.getCount(); i != e; ++i) {
-        MCSectionData::Fixup Fix(F, i * FF.getValueSize(),
-                                 FF.getValue(),FF.getValueSize());
-        SD.getFixups().push_back(Fix);
-      }
-      break;
-    }
-
     case MCFragment::FT_Org: {
       MCOrgFragment &OF = cast<MCOrgFragment>(F);
 
@@ -1051,6 +1060,64 @@ void MCAssembler::LayoutSection(MCSectionData &SD) {
     SD.setFileSize(Address - SD.getAddress());
 }
 
+/// WriteNopData - Write optimal nops to the output file for the \arg Count
+/// bytes.  This returns the number of bytes written.  It may return 0 if
+/// the \arg Count is more than the maximum optimal nops.
+///
+/// FIXME this is X86 32-bit specific and should move to a better place.
+static uint64_t WriteNopData(uint64_t Count, MachObjectWriter &MOW) {
+  static const uint8_t Nops[16][16] = {
+    // nop
+    {0x90},
+    // xchg %ax,%ax
+    {0x66, 0x90},
+    // nopl (%[re]ax)
+    {0x0f, 0x1f, 0x00},
+    // nopl 0(%[re]ax)
+    {0x0f, 0x1f, 0x40, 0x00},
+    // nopl 0(%[re]ax,%[re]ax,1)
+    {0x0f, 0x1f, 0x44, 0x00, 0x00},
+    // nopw 0(%[re]ax,%[re]ax,1)
+    {0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00},
+    // nopl 0L(%[re]ax)
+    {0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00},
+    // nopl 0L(%[re]ax,%[re]ax,1)
+    {0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00},
+    // nopw 0L(%[re]ax,%[re]ax,1)
+    {0x66, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00},
+    // nopw %cs:0L(%[re]ax,%[re]ax,1)
+    {0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00},
+    // nopl 0(%[re]ax,%[re]ax,1)
+    // nopw 0(%[re]ax,%[re]ax,1)
+    {0x0f, 0x1f, 0x44, 0x00, 0x00,
+     0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00},
+    // nopw 0(%[re]ax,%[re]ax,1)
+    // nopw 0(%[re]ax,%[re]ax,1)
+    {0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00,
+     0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00},
+    // nopw 0(%[re]ax,%[re]ax,1)
+    // nopl 0L(%[re]ax) */
+    {0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00,
+     0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00},
+    // nopl 0L(%[re]ax)
+    // nopl 0L(%[re]ax)
+    {0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00,
+     0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00},
+    // nopl 0L(%[re]ax)
+    // nopl 0L(%[re]ax,%[re]ax,1)
+    {0x0f, 0x1f, 0x80, 0x00, 0x00, 0x00, 0x00,
+     0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00}
+  };
+
+  if (Count > 15)
+    return 0;
+
+  for (uint64_t i = 0; i < Count; i++)
+    MOW.Write8 (uint8_t(Nops[Count - 1][i]));
+
+  return Count;
+}
+
 /// WriteFileData - Write the \arg F data to the output file.
 static void WriteFileData(raw_ostream &OS, const MCFragment &F,
                           MachObjectWriter &MOW) {
@@ -1074,6 +1141,14 @@ static void WriteFileData(raw_ostream &OS, const MCFragment &F,
                         "' is not a divisor of padding size '" +
                         Twine(AF.getFileSize()) + "'");
 
+    // See if we are aligning with nops, and if so do that first to try to fill
+    // the Count bytes.  Then if that did not fill any bytes or there are any
+    // bytes left to fill use the the Value and ValueSize to fill the rest.
+    if (AF.getEmitNops()) {
+      uint64_t NopByteCount = WriteNopData(Count, MOW);
+      Count -= NopByteCount;
+    }
+
     for (uint64_t i = 0; i != Count; ++i) {
       switch (AF.getValueSize()) {
       default:
@@ -1087,39 +1162,30 @@ static void WriteFileData(raw_ostream &OS, const MCFragment &F,
     break;
   }
 
-  case MCFragment::FT_Data:
+  case MCFragment::FT_Data: {
+    MCDataFragment &DF = cast<MCDataFragment>(F);
+
+    // Apply the fixups.
+    //
+    // FIXME: Move elsewhere.
+    for (MCDataFragment::const_fixup_iterator it = DF.fixup_begin(),
+           ie = DF.fixup_end(); it != ie; ++it)
+      MOW.ApplyFixup(*it, DF);
+
     OS << cast<MCDataFragment>(F).getContents().str();
     break;
+  }
 
   case MCFragment::FT_Fill: {
     MCFillFragment &FF = cast<MCFillFragment>(F);
-
-    int64_t Value = 0;
-
-    MCValue Target;
-    if (!FF.getValue().EvaluateAsRelocatable(Target))
-      llvm_report_error("expected relocatable expression");
-
-    if (Target.isAbsolute())
-      Value = Target.getConstant();
     for (uint64_t i = 0, e = FF.getCount(); i != e; ++i) {
-      if (!Target.isAbsolute()) {
-        // Find the fixup.
-        //
-        // FIXME: Find a better way to write in the fixes.
-        const MCSectionData::Fixup *Fixup =
-          F.getParent()->LookupFixup(&F, i * FF.getValueSize());
-        assert(Fixup && "Missing fixup for fill value!");
-        Value = Fixup->FixedValue;
-      }
-
       switch (FF.getValueSize()) {
       default:
         assert(0 && "Invalid size!");
-      case 1: MOW.Write8 (uint8_t (Value)); break;
-      case 2: MOW.Write16(uint16_t(Value)); break;
-      case 4: MOW.Write32(uint32_t(Value)); break;
-      case 8: MOW.Write64(uint64_t(Value)); break;
+      case 1: MOW.Write8 (uint8_t (FF.getValue())); break;
+      case 2: MOW.Write16(uint16_t(FF.getValue())); break;
+      case 4: MOW.Write32(uint32_t(FF.getValue())); break;
+      case 8: MOW.Write64(uint64_t(FF.getValue())); break;
       }
     }
     break;
@@ -1167,6 +1233,10 @@ static void WriteFileData(raw_ostream &OS, const MCSectionData &SD,
 }
 
 void MCAssembler::Finish() {
+  DEBUG_WITH_TYPE("mc-dump", {
+      llvm::errs() << "assembler backend - pre-layout\n--\n";
+      dump(); });
+
   // Layout the concrete sections and fragments.
   uint64_t Address = 0;
   MCSectionData *Prev = 0;
@@ -1205,9 +1275,149 @@ void MCAssembler::Finish() {
     Address += SD.getSize();
   }
 
+  DEBUG_WITH_TYPE("mc-dump", {
+      llvm::errs() << "assembler backend - post-layout\n--\n";
+      dump(); });
+
   // Write the object file.
   MachObjectWriter MOW(OS);
   MOW.WriteObject(*this);
 
   OS.flush();
 }
+
+
+// Debugging methods
+
+namespace llvm {
+
+raw_ostream &operator<<(raw_ostream &OS, const MCAsmFixup &AF) {
+  OS << "<MCAsmFixup" << " Offset:" << AF.Offset << " Value:" << *AF.Value
+     << " Kind:" << AF.Kind << ">";
+  return OS;
+}
+
+}
+
+void MCFragment::dump() {
+  raw_ostream &OS = llvm::errs();
+
+  OS << "<MCFragment " << (void*) this << " Offset:" << Offset
+     << " FileSize:" << FileSize;
+
+  OS << ">";
+}
+
+void MCAlignFragment::dump() {
+  raw_ostream &OS = llvm::errs();
+
+  OS << "<MCAlignFragment ";
+  this->MCFragment::dump();
+  OS << "\n       ";
+  OS << " Alignment:" << getAlignment()
+     << " Value:" << getValue() << " ValueSize:" << getValueSize()
+     << " MaxBytesToEmit:" << getMaxBytesToEmit() << ">";
+}
+
+void MCDataFragment::dump() {
+  raw_ostream &OS = llvm::errs();
+
+  OS << "<MCDataFragment ";
+  this->MCFragment::dump();
+  OS << "\n       ";
+  OS << " Contents:[";
+  for (unsigned i = 0, e = getContents().size(); i != e; ++i) {
+    if (i) OS << ",";
+    OS << hexdigit((Contents[i] >> 4) & 0xF) << hexdigit(Contents[i] & 0xF);
+  }
+  OS << "] (" << getContents().size() << " bytes)";
+
+  if (!getFixups().empty()) {
+    OS << ",\n       ";
+    OS << " Fixups:[";
+    for (fixup_iterator it = fixup_begin(), ie = fixup_end(); it != ie; ++it) {
+      if (it != fixup_begin()) OS << ",\n            ";
+      OS << *it;
+    }
+    OS << "]";
+  }
+
+  OS << ">";
+}
+
+void MCFillFragment::dump() {
+  raw_ostream &OS = llvm::errs();
+
+  OS << "<MCFillFragment ";
+  this->MCFragment::dump();
+  OS << "\n       ";
+  OS << " Value:" << getValue() << " ValueSize:" << getValueSize()
+     << " Count:" << getCount() << ">";
+}
+
+void MCOrgFragment::dump() {
+  raw_ostream &OS = llvm::errs();
+
+  OS << "<MCOrgFragment ";
+  this->MCFragment::dump();
+  OS << "\n       ";
+  OS << " Offset:" << getOffset() << " Value:" << getValue() << ">";
+}
+
+void MCZeroFillFragment::dump() {
+  raw_ostream &OS = llvm::errs();
+
+  OS << "<MCZeroFillFragment ";
+  this->MCFragment::dump();
+  OS << "\n       ";
+  OS << " Size:" << getSize() << " Alignment:" << getAlignment() << ">";
+}
+
+void MCSectionData::dump() {
+  raw_ostream &OS = llvm::errs();
+
+  OS << "<MCSectionData";
+  OS << " Alignment:" << getAlignment() << " Address:" << Address
+     << " Size:" << Size << " FileSize:" << FileSize
+     << " Fragments:[";
+  for (iterator it = begin(), ie = end(); it != ie; ++it) {
+    if (it != begin()) OS << ",\n      ";
+    it->dump();
+  }
+  OS << "]>";
+}
+
+void MCSymbolData::dump() {
+  raw_ostream &OS = llvm::errs();
+
+  OS << "<MCSymbolData Symbol:" << getSymbol()
+     << " Fragment:" << getFragment() << " Offset:" << getOffset()
+     << " Flags:" << getFlags() << " Index:" << getIndex();
+  if (isCommon())
+    OS << " (common, size:" << getCommonSize()
+       << " align: " << getCommonAlignment() << ")";
+  if (isExternal())
+    OS << " (external)";
+  if (isPrivateExtern())
+    OS << " (private extern)";
+  OS << ">";
+}
+
+void MCAssembler::dump() {
+  raw_ostream &OS = llvm::errs();
+
+  OS << "<MCAssembler\n";
+  OS << "  Sections:[";
+  for (iterator it = begin(), ie = end(); it != ie; ++it) {
+    if (it != begin()) OS << ",\n    ";
+    it->dump();
+  }
+  OS << "],\n";
+  OS << "  Symbols:[";
+
+  for (symbol_iterator it = symbol_begin(), ie = symbol_end(); it != ie; ++it) {
+    if (it != symbol_begin()) OS << ",\n    ";
+    it->dump();
+  }
+  OS << "]>\n";
+}
diff --git a/lib/MC/MCCodeEmitter.cpp b/lib/MC/MCCodeEmitter.cpp
index c122763..accb06c 100644
--- a/lib/MC/MCCodeEmitter.cpp
+++ b/lib/MC/MCCodeEmitter.cpp
@@ -16,3 +16,15 @@ MCCodeEmitter::MCCodeEmitter() {
 
 MCCodeEmitter::~MCCodeEmitter() {
 }
+
+const MCFixupKindInfo &MCCodeEmitter::getFixupKindInfo(MCFixupKind Kind) const {
+  static const MCFixupKindInfo Builtins[] = {
+    { "FK_Data_1", 0, 8 },
+    { "FK_Data_2", 0, 16 },
+    { "FK_Data_4", 0, 32 },
+    { "FK_Data_8", 0, 64 }
+  };
+  
+  assert(Kind <= 3 && "Unknown fixup kind");
+  return Builtins[Kind];
+}
diff --git a/lib/MC/MCInstPrinter.cpp b/lib/MC/MCInstPrinter.cpp
index e90c03c..92a7154 100644
--- a/lib/MC/MCInstPrinter.cpp
+++ b/lib/MC/MCInstPrinter.cpp
@@ -8,7 +8,14 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/MC/MCInstPrinter.h"
+#include "llvm/ADT/StringRef.h"
 using namespace llvm;
 
 MCInstPrinter::~MCInstPrinter() {
 }
+
+/// getOpcodeName - Return the name of the specified opcode enum (e.g.
+/// "MOV32ri") or empty if we can't resolve it.
+StringRef MCInstPrinter::getOpcodeName(unsigned Opcode) const {
+  return "";
+}
diff --git a/lib/MC/MCMachOStreamer.cpp b/lib/MC/MCMachOStreamer.cpp
index 99a819f..a7a8a5d 100644
--- a/lib/MC/MCMachOStreamer.cpp
+++ b/lib/MC/MCMachOStreamer.cpp
@@ -137,6 +137,8 @@ public:
   virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
                                     unsigned ValueSize = 1,
                                     unsigned MaxBytesToEmit = 0);
+  virtual void EmitCodeAlignment(unsigned ByteAlignment,
+                                 unsigned MaxBytesToEmit = 0);
   virtual void EmitValueToOffset(const MCExpr *Offset,
                                  unsigned char Value = 0);
   
@@ -333,7 +335,22 @@ void MCMachOStreamer::EmitBytes(StringRef Data, unsigned AddrSpace) {
 
 void MCMachOStreamer::EmitValue(const MCExpr *Value, unsigned Size,
                                 unsigned AddrSpace) {
-  new MCFillFragment(*AddValueSymbols(Value), Size, 1, CurSectionData);
+  MCDataFragment *DF = dyn_cast_or_null<MCDataFragment>(getCurrentFragment());
+  if (!DF)
+    DF = new MCDataFragment(CurSectionData);
+
+  // Avoid fixups when possible.
+  int64_t AbsValue;
+  if (AddValueSymbols(Value)->EvaluateAsAbsolute(AbsValue)) {
+    // FIXME: Endianness assumption.
+    for (unsigned i = 0; i != Size; ++i)
+      DF->getContents().push_back(uint8_t(AbsValue >> (i * 8)));
+  } else {
+    DF->getFixups().push_back(MCAsmFixup(DF->getContents().size(),
+                                         *AddValueSymbols(Value),
+                                         MCFixup::getKindForSize(Size)));
+    DF->getContents().resize(DF->getContents().size() + Size, 0);
+  }
 }
 
 void MCMachOStreamer::EmitValueToAlignment(unsigned ByteAlignment,
@@ -342,7 +359,20 @@ void MCMachOStreamer::EmitValueToAlignment(unsigned ByteAlignment,
   if (MaxBytesToEmit == 0)
     MaxBytesToEmit = ByteAlignment;
   new MCAlignFragment(ByteAlignment, Value, ValueSize, MaxBytesToEmit,
-                      CurSectionData);
+                      false /* EmitNops */, CurSectionData);
+
+  // Update the maximum alignment on the current section if necessary.
+  if (ByteAlignment > CurSectionData->getAlignment())
+    CurSectionData->setAlignment(ByteAlignment);
+}
+
+void MCMachOStreamer::EmitCodeAlignment(unsigned ByteAlignment,
+                                        unsigned MaxBytesToEmit) {
+  if (MaxBytesToEmit == 0)
+    MaxBytesToEmit = ByteAlignment;
+  // FIXME the 0x90 is the default x86 1 byte nop opcode.
+  new MCAlignFragment(ByteAlignment, 0x90, 1, MaxBytesToEmit,
+                      true /* EmitNops */, CurSectionData);
 
   // Update the maximum alignment on the current section if necessary.
   if (ByteAlignment > CurSectionData->getAlignment())
@@ -365,12 +395,23 @@ void MCMachOStreamer::EmitInstruction(const MCInst &Inst) {
 
   CurSectionData->setHasInstructions(true);
 
-  // FIXME: Relocations!
   SmallVector<MCFixup, 4> Fixups;
   SmallString<256> Code;
   raw_svector_ostream VecOS(Code);
   Emitter->EncodeInstruction(Inst, VecOS, Fixups);
-  EmitBytes(VecOS.str(), 0);
+  VecOS.flush();
+
+  // Add the fixups and data.
+  MCDataFragment *DF = dyn_cast_or_null<MCDataFragment>(getCurrentFragment());
+  if (!DF)
+    DF = new MCDataFragment(CurSectionData);
+  for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
+    MCFixup &F = Fixups[i];
+    DF->getFixups().push_back(MCAsmFixup(DF->getContents().size()+F.getOffset(),
+                                         *F.getValue(),
+                                         F.getKind()));
+  }
+  DF->getContents().append(Code.begin(), Code.end());
 }
 
 void MCMachOStreamer::Finish() {
diff --git a/lib/MC/MCNullStreamer.cpp b/lib/MC/MCNullStreamer.cpp
index 46e9ebf..ab61799 100644
--- a/lib/MC/MCNullStreamer.cpp
+++ b/lib/MC/MCNullStreamer.cpp
@@ -55,6 +55,9 @@ namespace {
                                       unsigned ValueSize = 1,
                                       unsigned MaxBytesToEmit = 0) {}
 
+    virtual void EmitCodeAlignment(unsigned ByteAlignment,
+                                   unsigned MaxBytesToEmit = 0) {}
+
     virtual void EmitValueToOffset(const MCExpr *Offset,
                                    unsigned char Value = 0) {}
     
diff --git a/lib/MC/MCParser/AsmParser.cpp b/lib/MC/MCParser/AsmParser.cpp
index d5bc396..6185c30 100644
--- a/lib/MC/MCParser/AsmParser.cpp
+++ b/lib/MC/MCParser/AsmParser.cpp
@@ -146,7 +146,7 @@ bool AsmParser::Run() {
   // FIXME: Target hook & command line option for initial section.
   Out.SwitchSection(getMachOSection("__TEXT", "__text",
                                     MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
-                                    0, SectionKind()));
+                                    0, SectionKind::getText()));
 
 
   // Prime the lexer.
@@ -325,9 +325,17 @@ bool AsmParser::ParseExpression(const MCExpr *&Res) {
 ///  expr ::= primaryexpr
 ///
 bool AsmParser::ParseExpression(const MCExpr *&Res, SMLoc &EndLoc) {
+  // Parse the expression.
   Res = 0;
-  return ParsePrimaryExpr(Res, EndLoc) ||
-         ParseBinOpRHS(1, Res, EndLoc);
+  if (ParsePrimaryExpr(Res, EndLoc) || ParseBinOpRHS(1, Res, EndLoc))
+    return true;
+
+  // Try to constant fold it up front, if possible.
+  int64_t Value;
+  if (Res->EvaluateAsAbsolute(Value))
+    Res = MCConstantExpr::Create(Value, getContext());
+
+  return false;
 }
 
 bool AsmParser::ParseParenExpression(const MCExpr *&Res, SMLoc &EndLoc) {
@@ -906,8 +914,10 @@ bool AsmParser::ParseDirectiveDarwinSection() {
     return Error(Loc, ErrorStr.c_str());
   
   // FIXME: Arch specific.
+  bool isText = Segment == "__TEXT";  // FIXME: Hack.
   Out.SwitchSection(getMachOSection(Segment, Section, TAA, StubSize,
-                                    SectionKind()));
+                                    isText ? SectionKind::getText()
+                                           : SectionKind::getDataRel()));
   return false;
 }
 
@@ -921,8 +931,10 @@ bool AsmParser::ParseDirectiveSectionSwitch(const char *Segment,
   Lex();
   
   // FIXME: Arch specific.
+  bool isText = StringRef(Segment) == "__TEXT";  // FIXME: Hack.
   Out.SwitchSection(getMachOSection(Segment, Section, TAA, StubSize,
-                                    SectionKind()));
+                                    isText ? SectionKind::getText()
+                                    : SectionKind::getDataRel()));
 
   // Set the implicit alignment, if any.
   //
@@ -1229,8 +1241,14 @@ bool AsmParser::ParseDirectiveAlign(bool IsPow2, unsigned ValueSize) {
     }
   }
 
-  // FIXME: Target specific behavior about how the "extra" bytes are filled.
-  Out.EmitValueToAlignment(Alignment, FillExpr, ValueSize, MaxBytesToFill);
+  // FIXME: hard code the parser to use EmitCodeAlignment for text when using
+  // the TextAlignFillValue.
+  if(Out.getCurrentSection()->getKind().isText() && 
+     Lexer.getMAI().getTextAlignFillValue() == FillExpr)
+    Out.EmitCodeAlignment(Alignment, MaxBytesToFill);
+  else
+    // FIXME: Target specific behavior about how the "extra" bytes are filled.
+    Out.EmitValueToAlignment(Alignment, FillExpr, ValueSize, MaxBytesToFill);
 
   return false;
 }
@@ -1354,7 +1372,7 @@ bool AsmParser::ParseDirectiveComm(bool IsLocal) {
   if (IsLocal) {
     Out.EmitZerofill(getMachOSection("__DATA", "__bss",
                                      MCSectionMachO::S_ZEROFILL, 0,
-                                     SectionKind()),
+                                     SectionKind::getBSS()),
                      Sym, Size, 1 << Pow2Alignment);
     return false;
   }
@@ -1390,7 +1408,7 @@ bool AsmParser::ParseDirectiveDarwinZerofill() {
     // Create the zerofill section but no symbol
     Out.EmitZerofill(getMachOSection(Segment, Section,
                                      MCSectionMachO::S_ZEROFILL, 0,
-                                     SectionKind()));
+                                     SectionKind::getBSS()));
     return false;
   }
 
@@ -1448,7 +1466,7 @@ bool AsmParser::ParseDirectiveDarwinZerofill() {
   // FIXME: Arch specific.
   Out.EmitZerofill(getMachOSection(Segment, Section,
                                  MCSectionMachO::S_ZEROFILL, 0,
-                                 SectionKind()),
+                                 SectionKind::getBSS()),
                    Sym, Size, 1 << Pow2Alignment);
 
   return false;
diff --git a/lib/MC/MCSectionMachO.cpp b/lib/MC/MCSectionMachO.cpp
index 6cc67a2..370aad1 100644
--- a/lib/MC/MCSectionMachO.cpp
+++ b/lib/MC/MCSectionMachO.cpp
@@ -10,6 +10,7 @@
 #include "llvm/MC/MCSectionMachO.h"
 #include "llvm/MC/MCContext.h"
 #include "llvm/Support/raw_ostream.h"
+#include <ctype.h>
 using namespace llvm;
 
 /// SectionTypeDescriptors - These are strings that describe the various section
diff --git a/lib/MC/TargetAsmBackend.cpp b/lib/MC/TargetAsmBackend.cpp
new file mode 100644
index 0000000..918d272
--- /dev/null
+++ b/lib/MC/TargetAsmBackend.cpp
@@ -0,0 +1,19 @@
+//===-- TargetAsmBackend.cpp - Target Assembly Backend ---------------------==//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Target/TargetAsmBackend.h"
+using namespace llvm;
+
+TargetAsmBackend::TargetAsmBackend(const Target &T)
+  : TheTarget(T)
+{
+}
+
+TargetAsmBackend::~TargetAsmBackend() {
+}