MC: Add WinCOFFStreamer implementation and merge common code from MachO

into MCObjectStreamer.

Origonal Windows COFF implementation by Nathan Jedffords.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108678 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 239 insertions, 81 deletions

diff --git a/lib/MC/MCMachOStreamer.cpp b/lib/MC/MCMachOStreamer.cpp
index 44bc267..ffae642 100644
--- a/lib/MC/MCMachOStreamer.cpp
+++ b/lib/MC/MCMachOStreamer.cpp
@@ -28,24 +28,6 @@ namespace {
 
 class MCMachOStreamer : public MCObjectStreamer {
 private:
-  MCFragment *getCurrentFragment() const {
-    assert(getCurrentSectionData() && "No current section!");
-
-    if (!getCurrentSectionData()->empty())
-      return &getCurrentSectionData()->getFragmentList().back();
-
-    return 0;
-  }
-
-  /// Get a data fragment to write into, creating a new one if the current
-  /// fragment is not a data fragment.
-  MCDataFragment *getOrCreateDataFragment() const {
-    MCDataFragment *F = dyn_cast_or_null<MCDataFragment>(getCurrentFragment());
-    if (!F)
-      F = new MCDataFragment(getCurrentSectionData());
-    return F;
-  }
-
   void EmitInstToFragment(const MCInst &Inst);
   void EmitInstToData(const MCInst &Inst);
 
@@ -54,32 +36,6 @@ public:
                   raw_ostream &OS, MCCodeEmitter *Emitter)
     : MCObjectStreamer(Context, TAB, OS, Emitter) {}
 
-  const MCExpr *AddValueSymbols(const MCExpr *Value) {
-    switch (Value->getKind()) {
-    case MCExpr::Target: assert(0 && "Can't handle target exprs yet!");
-    case MCExpr::Constant:
-      break;
-
-    case MCExpr::Binary: {
-      const MCBinaryExpr *BE = cast<MCBinaryExpr>(Value);
-      AddValueSymbols(BE->getLHS());
-      AddValueSymbols(BE->getRHS());
-      break;
-    }
-
-    case MCExpr::SymbolRef:
-      getAssembler().getOrCreateSymbolData(
-        cast<MCSymbolRefExpr>(Value)->getSymbol());
-      break;
-
-    case MCExpr::Unary:
-      AddValueSymbols(cast<MCUnaryExpr>(Value)->getSubExpr());
-      break;
-    }
-
-    return Value;
-  }
-
   /// @name MCStreamer Interface
   /// @{
 
@@ -142,6 +98,8 @@ public:
 } // end anonymous namespace.
 
 void MCMachOStreamer::EmitLabel(MCSymbol *Symbol) {
+  // TODO: This is almost exactly the same as WinCOFFStreamer. Consider merging
+  // into MCObjectStreamer.
   assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
   assert(!Symbol->isVariable() && "Cannot emit a variable symbol!");
   assert(CurSection && "Cannot emit before setting section!");
@@ -185,6 +143,8 @@ void MCMachOStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
 }
 
 void MCMachOStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
+  // TODO: This is exactly the same as WinCOFFStreamer. Consider merging into
+  // MCObjectStreamer.
   // FIXME: Lift context changes into super class.
   getAssembler().getOrCreateSymbolData(*Symbol);
   Symbol->setVariableValue(AddValueSymbols(Value));
@@ -335,11 +295,15 @@ void MCMachOStreamer::EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
 }
 
 void MCMachOStreamer::EmitBytes(StringRef Data, unsigned AddrSpace) {
+  // TODO: This is exactly the same as WinCOFFStreamer. Consider merging into
+  // MCObjectStreamer.
   getOrCreateDataFragment()->getContents().append(Data.begin(), Data.end());
 }
 
 void MCMachOStreamer::EmitValue(const MCExpr *Value, unsigned Size,
                                 unsigned AddrSpace) {
+  // TODO: This is exactly the same as WinCOFFStreamer. Consider merging into
+  // MCObjectStreamer.
   MCDataFragment *DF = getOrCreateDataFragment();
 
   // Avoid fixups when possible.
@@ -359,6 +323,8 @@ void MCMachOStreamer::EmitValue(const MCExpr *Value, unsigned Size,
 void MCMachOStreamer::EmitValueToAlignment(unsigned ByteAlignment,
                                            int64_t Value, unsigned ValueSize,
                                            unsigned MaxBytesToEmit) {
+  // TODO: This is exactly the same as WinCOFFStreamer. Consider merging into
+  // MCObjectStreamer.
   if (MaxBytesToEmit == 0)
     MaxBytesToEmit = ByteAlignment;
   new MCAlignFragment(ByteAlignment, Value, ValueSize, MaxBytesToEmit,
@@ -371,6 +337,8 @@ void MCMachOStreamer::EmitValueToAlignment(unsigned ByteAlignment,
 
 void MCMachOStreamer::EmitCodeAlignment(unsigned ByteAlignment,
                                         unsigned MaxBytesToEmit) {
+  // TODO: This is exactly the same as WinCOFFStreamer. Consider merging into
+  // MCObjectStreamer.
   if (MaxBytesToEmit == 0)
     MaxBytesToEmit = ByteAlignment;
   MCAlignFragment *F = new MCAlignFragment(ByteAlignment, 0, 1, MaxBytesToEmit,
diff --git a/lib/MC/MCObjectStreamer.cpp b/lib/MC/MCObjectStreamer.cpp
index d3f7f77..9050b3e 100644
--- a/lib/MC/MCObjectStreamer.cpp
+++ b/lib/MC/MCObjectStreamer.cpp
@@ -9,7 +9,9 @@
 
 #include "llvm/MC/MCObjectStreamer.h"
 
+#include "llvm/Support/ErrorHandling.h"
 #include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCExpr.h"
 using namespace llvm;
 
 MCObjectStreamer::MCObjectStreamer(MCContext &Context, TargetAsmBackend &TAB,
@@ -24,6 +26,47 @@ MCObjectStreamer::~MCObjectStreamer() {
   delete Assembler;
 }
 
+MCFragment *MCObjectStreamer::getCurrentFragment() const {
+  assert(getCurrentSectionData() && "No current section!");
+
+  if (!getCurrentSectionData()->empty())
+    return &getCurrentSectionData()->getFragmentList().back();
+
+  return 0;
+}
+
+MCDataFragment *MCObjectStreamer::getOrCreateDataFragment() const {
+  MCDataFragment *F = dyn_cast_or_null<MCDataFragment>(getCurrentFragment());
+  if (!F)
+    F = new MCDataFragment(getCurrentSectionData());
+  return F;
+}
+
+const MCExpr *MCObjectStreamer::AddValueSymbols(const MCExpr *Value) {
+  switch (Value->getKind()) {
+  case MCExpr::Target: llvm_unreachable("Can't handle target exprs yet!");
+  case MCExpr::Constant:
+    break;
+
+  case MCExpr::Binary: {
+    const MCBinaryExpr *BE = cast<MCBinaryExpr>(Value);
+    AddValueSymbols(BE->getLHS());
+    AddValueSymbols(BE->getRHS());
+    break;
+  }
+
+  case MCExpr::SymbolRef:
+    Assembler->getOrCreateSymbolData(cast<MCSymbolRefExpr>(Value)->getSymbol());
+    break;
+
+  case MCExpr::Unary:
+    AddValueSymbols(cast<MCUnaryExpr>(Value)->getSubExpr());
+    break;
+  }
+
+  return Value;
+}
+
 void MCObjectStreamer::SwitchSection(const MCSection *Section) {
   assert(Section && "Cannot switch to a null section!");
 
diff --git a/lib/MC/WinCOFFStreamer.cpp b/lib/MC/WinCOFFStreamer.cpp
index 1030cdb..71557f0 100644
--- a/lib/MC/WinCOFFStreamer.cpp
+++ b/lib/MC/WinCOFFStreamer.cpp
@@ -18,27 +18,34 @@
 #include "llvm/MC/MCSection.h"
 #include "llvm/MC/MCSymbol.h"
 #include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCValue.h"
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCAsmLayout.h"
 #include "llvm/MC/MCCodeEmitter.h"
 #include "llvm/MC/MCSectionCOFF.h"
+#include "llvm/Target/TargetRegistry.h"
 #include "llvm/Target/TargetAsmBackend.h"
+#include "llvm/ADT/StringMap.h"
+
 #include "llvm/Support/COFF.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/raw_ostream.h"
 using namespace llvm;
 
-#define dbg_notimpl(x) \
-  do { dbgs() << "not implemented, " << __FUNCTION__  << " (" << x << ")"; \
-    abort(); } while (false);
-
 namespace {
 class WinCOFFStreamer : public MCObjectStreamer {
 public:
+  MCSymbol const *CurSymbol;
+
   WinCOFFStreamer(MCContext &Context,
                   TargetAsmBackend &TAB,
                   MCCodeEmitter &CE,
                   raw_ostream &OS);
 
+  void AddCommonSymbol(MCSymbol *Symbol, uint64_t Size,
+                       unsigned ByteAlignment, bool External);
+
   // MCStreamer interface
 
   virtual void EmitLabel(MCSymbol *Symbol);
@@ -52,18 +59,18 @@ public:
   virtual void EndCOFFSymbolDef();
   virtual void EmitELFSize(MCSymbol *Symbol, const MCExpr *Value);
   virtual void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
-                        unsigned ByteAlignment);
+                                unsigned ByteAlignment);
   virtual void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size);
   virtual void EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
-                    unsigned Size,unsigned ByteAlignment);
+                            unsigned Size,unsigned ByteAlignment);
   virtual void EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
-                      uint64_t Size, unsigned ByteAlignment);
+                              uint64_t Size, unsigned ByteAlignment);
   virtual void EmitBytes(StringRef Data, unsigned AddrSpace);
-  virtual void EmitValue(const MCExpr *Value, unsigned Size, 
+  virtual void EmitValue(const MCExpr *Value, unsigned Size,
                          unsigned AddrSpace);
   virtual void EmitGPRel32Value(const MCExpr *Value);
   virtual void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
-                            unsigned ValueSize, unsigned MaxBytesToEmit);
+                                   unsigned ValueSize, unsigned MaxBytesToEmit);
   virtual void EmitCodeAlignment(unsigned ByteAlignment,
                                  unsigned MaxBytesToEmit);
   virtual void EmitValueToOffset(const MCExpr *Offset, unsigned char Value);
@@ -78,96 +85,223 @@ WinCOFFStreamer::WinCOFFStreamer(MCContext &Context,
                                  TargetAsmBackend &TAB,
                                  MCCodeEmitter &CE,
                                  raw_ostream &OS)
-    : MCObjectStreamer(Context, TAB, OS, &CE) {
+    : MCObjectStreamer(Context, TAB, OS, &CE)
+    , CurSymbol(NULL) {
+}
+
+void WinCOFFStreamer::AddCommonSymbol(MCSymbol *Symbol, uint64_t Size,
+                                      unsigned ByteAlignment, bool External) {
+  assert(!Symbol->isInSection() && "Symbol must not already have a section!");
+
+  std::string SectionName(".bss$linkonce");
+  SectionName.append(Symbol->getName().begin(), Symbol->getName().end());
+
+  MCSymbolData &SymbolData = getAssembler().getOrCreateSymbolData(*Symbol);
+
+  unsigned Characteristics =
+    COFF::IMAGE_SCN_LNK_COMDAT |
+    COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
+    COFF::IMAGE_SCN_MEM_READ |
+    COFF::IMAGE_SCN_MEM_WRITE;
+
+  int Selection = COFF::IMAGE_COMDAT_SELECT_LARGEST;
+
+  const MCSection *Section = MCStreamer::getContext().getCOFFSection(
+    SectionName, Characteristics, Selection, SectionKind::getBSS());
+
+  MCSectionData &SectionData = getAssembler().getOrCreateSectionData(*Section);
+
+  if (SectionData.getAlignment() < ByteAlignment)
+    SectionData.setAlignment(ByteAlignment);
+
+  SymbolData.setExternal(External);
+
+  Symbol->setSection(*Section);
+
+  if (ByteAlignment != 1)
+      new MCAlignFragment(ByteAlignment, 0, 0, ByteAlignment, &SectionData);
+
+  SymbolData.setFragment(new MCFillFragment(0, 0, Size, &SectionData));
 }
 
 // MCStreamer interface
 
 void WinCOFFStreamer::EmitLabel(MCSymbol *Symbol) {
+  // TODO: This is copied almost exactly from the MachOStreamer. Consider
+  // merging into MCObjectStreamer?
+  assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
+  assert(!Symbol->isVariable() && "Cannot emit a variable symbol!");
+  assert(CurSection && "Cannot emit before setting section!");
+
+  Symbol->setSection(*CurSection);
+
+  MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
+
+  // FIXME: This is wasteful, we don't necessarily need to create a data
+  // fragment. Instead, we should mark the symbol as pointing into the data
+  // fragment if it exists, otherwise we should just queue the label and set its
+  // fragment pointer when we emit the next fragment.
+  MCDataFragment *F = getOrCreateDataFragment();
+  assert(!SD.getFragment() && "Unexpected fragment on symbol data!");
+  SD.setFragment(F);
+  SD.setOffset(F->getContents().size());
 }
 
 void WinCOFFStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
-  dbg_notimpl("Flag = " << Flag);
+  llvm_unreachable("not implemented");
 }
 
 void WinCOFFStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
+  // TODO: This is exactly the same as MachOStreamer. Consider merging into
+  // MCObjectStreamer.
+  getAssembler().getOrCreateSymbolData(*Symbol);
+  AddValueSymbols(Value);
+  Symbol->setVariableValue(Value);
 }
 
 void WinCOFFStreamer::EmitSymbolAttribute(MCSymbol *Symbol,
                                           MCSymbolAttr Attribute) {
+  switch (Attribute) {
+  case MCSA_WeakReference:
+    getAssembler().getOrCreateSymbolData(*Symbol).modifyFlags(
+      COFF::SF_WeakReference,
+      COFF::SF_WeakReference);
+    break;
+
+  case MCSA_Global:
+    getAssembler().getOrCreateSymbolData(*Symbol).setExternal(true);
+    break;
+
+  default:
+    llvm_unreachable("unsupported attribute");
+    break;
+  }
 }
 
 void WinCOFFStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
-  dbg_notimpl("Symbol = " << Symbol->getName() << ", DescValue = "<< DescValue);
+  llvm_unreachable("not implemented");
 }
 
 void WinCOFFStreamer::BeginCOFFSymbolDef(MCSymbol const *Symbol) {
+  assert(CurSymbol == NULL && "EndCOFFSymbolDef must be called between calls "
+                              "to BeginCOFFSymbolDef!");
+  CurSymbol = Symbol;
 }
 
 void WinCOFFStreamer::EmitCOFFSymbolStorageClass(int StorageClass) {
+  assert(CurSymbol != NULL && "BeginCOFFSymbolDef must be called first!");
+  assert((StorageClass & ~0xFF) == 0 && "StorageClass must only have data in "
+                                        "the first byte!");
+
+  getAssembler().getOrCreateSymbolData(*CurSymbol).modifyFlags(
+    StorageClass << COFF::SF_ClassShift,
+    COFF::SF_ClassMask);
 }
 
 void WinCOFFStreamer::EmitCOFFSymbolType(int Type) {
+  assert(CurSymbol != NULL && "BeginCOFFSymbolDef must be called first!");
+  assert((Type & ~0xFFFF) == 0 && "Type must only have data in the first 2 "
+                                  "bytes");
+
+  getAssembler().getOrCreateSymbolData(*CurSymbol).modifyFlags(
+    Type << COFF::SF_TypeShift,
+    COFF::SF_TypeMask);
 }
 
 void WinCOFFStreamer::EndCOFFSymbolDef() {
+  assert(CurSymbol != NULL && "BeginCOFFSymbolDef must be called first!");
+  CurSymbol = NULL;
 }
 
 void WinCOFFStreamer::EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {
-  dbg_notimpl("Symbol = " << Symbol->getName() << ", Value = " << *Value);
+  llvm_unreachable("not implemented");
 }
 
 void WinCOFFStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
-                                      unsigned ByteAlignment) {
+                                       unsigned ByteAlignment) {
+  AddCommonSymbol(Symbol, Size, ByteAlignment, true);
 }
 
 void WinCOFFStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size) {
+  AddCommonSymbol(Symbol, Size, 1, false);
 }
 
 void WinCOFFStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
-                                  unsigned Size,unsigned ByteAlignment) {
-  MCSectionCOFF const *SectionCOFF =
-    static_cast<MCSectionCOFF const *>(Section);
-
-  dbg_notimpl("Section = " << SectionCOFF->getSectionName() << ", Symbol = " <<
-              Symbol->getName() << ", Size = " << Size << ", ByteAlignment = "
-              << ByteAlignment);
+                                   unsigned Size,unsigned ByteAlignment) {
+  llvm_unreachable("not implemented");
 }
 
 void WinCOFFStreamer::EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
                                      uint64_t Size, unsigned ByteAlignment) {
-  MCSectionCOFF const *SectionCOFF =
-    static_cast<MCSectionCOFF const *>(Section);
-
-  dbg_notimpl("Section = " << SectionCOFF->getSectionName() << ", Symbol = " <<
-              Symbol->getName() << ", Size = " << Size << ", ByteAlignment = "
-              << ByteAlignment);
+  llvm_unreachable("not implemented");
 }
 
 void WinCOFFStreamer::EmitBytes(StringRef Data, unsigned AddrSpace) {
+  // TODO: This is copied exactly from the MachOStreamer. Consider merging into
+  // MCObjectStreamer?
+  getOrCreateDataFragment()->getContents().append(Data.begin(), Data.end());
 }
 
 void WinCOFFStreamer::EmitValue(const MCExpr *Value, unsigned Size,
-                               unsigned AddrSpace) {
+                                unsigned AddrSpace) {
+  assert(AddrSpace == 0 && "Address space must be 0!");
+
+  // TODO: This is copied exactly from the MachOStreamer. Consider merging into
+  // MCObjectStreamer?
+  MCDataFragment *DF = getOrCreateDataFragment();
+
+  // 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->addFixup(MCFixup::Create(DF->getContents().size(),
+                                 AddValueSymbols(Value),
+                                 MCFixup::getKindForSize(Size)));
+    DF->getContents().resize(DF->getContents().size() + Size, 0);
+  }
 }
 
 void WinCOFFStreamer::EmitGPRel32Value(const MCExpr *Value) {
-  dbg_notimpl("Value = '" << *Value);
+  llvm_unreachable("not implemented");
 }
 
 void WinCOFFStreamer::EmitValueToAlignment(unsigned ByteAlignment,
-                                          int64_t Value,
-                                          unsigned ValueSize,
-                                          unsigned MaxBytesToEmit) {
+                                           int64_t Value,
+                                           unsigned ValueSize,
+                                           unsigned MaxBytesToEmit) {
+  // TODO: This is copied exactly from the MachOStreamer. Consider merging into
+  // MCObjectStreamer?
+  if (MaxBytesToEmit == 0)
+    MaxBytesToEmit = ByteAlignment;
+  new MCAlignFragment(ByteAlignment, Value, ValueSize, MaxBytesToEmit,
+                      getCurrentSectionData());
+
+  // Update the maximum alignment on the current section if necessary.
+  if (ByteAlignment > getCurrentSectionData()->getAlignment())
+    getCurrentSectionData()->setAlignment(ByteAlignment);
 }
 
 void WinCOFFStreamer::EmitCodeAlignment(unsigned ByteAlignment,
-                                       unsigned MaxBytesToEmit = 0) {
+                                        unsigned MaxBytesToEmit) {
+  // TODO: This is copied exactly from the MachOStreamer. Consider merging into
+  // MCObjectStreamer?
+  if (MaxBytesToEmit == 0)
+    MaxBytesToEmit = ByteAlignment;
+  MCAlignFragment *F = new MCAlignFragment(ByteAlignment, 0, 1, MaxBytesToEmit,
+                                           getCurrentSectionData());
+  F->setEmitNops(true);
+
+  // Update the maximum alignment on the current section if necessary.
+  if (ByteAlignment > getCurrentSectionData()->getAlignment())
+    getCurrentSectionData()->setAlignment(ByteAlignment);
 }
 
 void WinCOFFStreamer::EmitValueToOffset(const MCExpr *Offset,
-                                       unsigned char Value = 0) {
-  dbg_notimpl("Offset = '" << *Offset << "', Value = " << Value);
+                                        unsigned char Value) {
+  llvm_unreachable("not implemented");
 }
 
 void WinCOFFStreamer::EmitFileDirective(StringRef Filename) {
@@ -176,11 +310,24 @@ void WinCOFFStreamer::EmitFileDirective(StringRef Filename) {
 }
 
 void WinCOFFStreamer::EmitDwarfFileDirective(unsigned FileNo,
-                                            StringRef Filename) {
-  dbg_notimpl("FileNo = " << FileNo << ", Filename = '" << Filename << "'");
+                                             StringRef Filename) {
+  llvm_unreachable("not implemented");
 }
 
 void WinCOFFStreamer::EmitInstruction(const MCInst &Instruction) {
+  for (unsigned i = 0, e = Instruction.getNumOperands(); i != e; ++i)
+    if (Instruction.getOperand(i).isExpr())
+      AddValueSymbols(Instruction.getOperand(i).getExpr());
+
+  getCurrentSectionData()->setHasInstructions(true);
+
+  MCInstFragment *Fragment =
+    new MCInstFragment(Instruction, getCurrentSectionData());
+
+  raw_svector_ostream VecOS(Fragment->getCode());
+
+  getAssembler().getEmitter().EncodeInstruction(Instruction, VecOS,
+                                                Fragment->getFixups());
 }
 
 void WinCOFFStreamer::Finish() {