X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FMC%2FMCObjectStreamer.cpp;h=bfa3c8cfa34d1ec53ab6e642f042b3d400f7f7e6;hb=640da197aedb73d1b12925fe4048cdd6d7fc7917;hp=3883f12152210208cd94f6c142aced5d0915f6de;hpb=484291c27319668ad99cb87def000254357736fb;p=oota-llvm.git

diff --git a/lib/MC/MCObjectStreamer.cpp b/lib/MC/MCObjectStreamer.cpp
index 3883f121522..bfa3c8cfa34 100644
--- a/lib/MC/MCObjectStreamer.cpp
+++ b/lib/MC/MCObjectStreamer.cpp
@@ -8,50 +8,73 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/MC/MCObjectStreamer.h"
-
-#include "llvm/Support/ErrorHandling.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/MC/MCAsmBackend.h"
+#include "llvm/MC/MCAsmInfo.h"
 #include "llvm/MC/MCAssembler.h"
 #include "llvm/MC/MCCodeEmitter.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCDwarf.h"
 #include "llvm/MC/MCExpr.h"
-#include "llvm/Target/TargetAsmBackend.h"
+#include "llvm/MC/MCObjectWriter.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Support/ErrorHandling.h"
 using namespace llvm;
 
-MCObjectStreamer::MCObjectStreamer(MCContext &Context, TargetAsmBackend &TAB,
-                                   raw_ostream &_OS, MCCodeEmitter *_Emitter,
-                                   bool _PadSectionToAlignment)
-  : MCStreamer(Context), Assembler(new MCAssembler(Context, TAB,
-                                                   *_Emitter,
-                                                   _PadSectionToAlignment,
-                                                   _OS)),
-    CurSectionData(0)
-{
-}
+MCObjectStreamer::MCObjectStreamer(MCContext &Context, MCAsmBackend &TAB,
+                                   raw_ostream &OS, MCCodeEmitter *Emitter_)
+    : MCStreamer(Context),
+      Assembler(new MCAssembler(Context, TAB, *Emitter_,
+                                *TAB.createObjectWriter(OS), OS)),
+      CurSectionData(0) {}
+
+MCObjectStreamer::MCObjectStreamer(MCContext &Context, MCAsmBackend &TAB,
+                                   raw_ostream &OS, MCCodeEmitter *Emitter_,
+                                   MCAssembler *_Assembler)
+    : MCStreamer(Context), Assembler(_Assembler), CurSectionData(0) {}
 
 MCObjectStreamer::~MCObjectStreamer() {
   delete &Assembler->getBackend();
   delete &Assembler->getEmitter();
+  delete &Assembler->getWriter();
   delete Assembler;
 }
 
+void MCObjectStreamer::reset() {
+  if (Assembler)
+    Assembler->reset();
+  CurSectionData = 0;
+  CurInsertionPoint = MCSectionData::iterator();
+  MCStreamer::reset();
+}
+
 MCFragment *MCObjectStreamer::getCurrentFragment() const {
   assert(getCurrentSectionData() && "No current section!");
 
-  if (!getCurrentSectionData()->empty())
-    return &getCurrentSectionData()->getFragmentList().back();
+  if (CurInsertionPoint != getCurrentSectionData()->getFragmentList().begin())
+    return prior(CurInsertionPoint);
 
   return 0;
 }
 
 MCDataFragment *MCObjectStreamer::getOrCreateDataFragment() const {
   MCDataFragment *F = dyn_cast_or_null<MCDataFragment>(getCurrentFragment());
-  if (!F)
-    F = new MCDataFragment(getCurrentSectionData());
+  // When bundling is enabled, we don't want to add data to a fragment that
+  // already has instructions (see MCELFStreamer::EmitInstToData for details)
+  if (!F || (Assembler->isBundlingEnabled() && F->hasInstructions())) {
+    F = new MCDataFragment();
+    insert(F);
+  }
   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::Target:
+    cast<MCTargetExpr>(Value)->AddValueSymbols(Assembler);
+    break;
+
   case MCExpr::Constant:
     break;
 
@@ -74,22 +97,295 @@ const MCExpr *MCObjectStreamer::AddValueSymbols(const MCExpr *Value) {
   return Value;
 }
 
+void MCObjectStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size) {
+  MCDataFragment *DF = getOrCreateDataFragment();
+
+  MCLineEntry::Make(this, getCurrentSection().first);
+
+  // Avoid fixups when possible.
+  int64_t AbsValue;
+  if (AddValueSymbols(Value)->EvaluateAsAbsolute(AbsValue, getAssembler())) {
+    EmitIntValue(AbsValue, Size);
+    return;
+  }
+  DF->getFixups().push_back(
+      MCFixup::Create(DF->getContents().size(), Value,
+                      MCFixup::getKindForSize(Size, false)));
+  DF->getContents().resize(DF->getContents().size() + Size, 0);
+}
+
+void MCObjectStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) {
+  RecordProcStart(Frame);
+}
+
+void MCObjectStreamer::EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) {
+  RecordProcEnd(Frame);
+}
+
+void MCObjectStreamer::EmitLabel(MCSymbol *Symbol) {
+  MCStreamer::EmitLabel(Symbol);
+
+  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 MCObjectStreamer::EmitDebugLabel(MCSymbol *Symbol) {
+  EmitLabel(Symbol);
+}
+
+void MCObjectStreamer::EmitULEB128Value(const MCExpr *Value) {
+  int64_t IntValue;
+  if (Value->EvaluateAsAbsolute(IntValue, getAssembler())) {
+    EmitULEB128IntValue(IntValue);
+    return;
+  }
+  Value = ForceExpAbs(Value);
+  insert(new MCLEBFragment(*Value, false));
+}
+
+void MCObjectStreamer::EmitSLEB128Value(const MCExpr *Value) {
+  int64_t IntValue;
+  if (Value->EvaluateAsAbsolute(IntValue, getAssembler())) {
+    EmitSLEB128IntValue(IntValue);
+    return;
+  }
+  Value = ForceExpAbs(Value);
+  insert(new MCLEBFragment(*Value, true));
+}
+
 void MCObjectStreamer::EmitWeakReference(MCSymbol *Alias,
                                          const MCSymbol *Symbol) {
   report_fatal_error("This file format doesn't support weak aliases.");
 }
 
-void MCObjectStreamer::SwitchSection(const MCSection *Section) {
+void MCObjectStreamer::ChangeSection(const MCSection *Section,
+                                     const MCExpr *Subsection) {
   assert(Section && "Cannot switch to a null section!");
 
-  // If already in this section, then this is a noop.
-  if (Section == CurSection) return;
-
-  PrevSection = CurSection;
-  CurSection = Section;
   CurSectionData = &getAssembler().getOrCreateSectionData(*Section);
+
+  int64_t IntSubsection = 0;
+  if (Subsection &&
+      !Subsection->EvaluateAsAbsolute(IntSubsection, getAssembler()))
+    report_fatal_error("Cannot evaluate subsection number");
+  if (IntSubsection < 0 || IntSubsection > 8192)
+    report_fatal_error("Subsection number out of range");
+  CurInsertionPoint =
+    CurSectionData->getSubsectionInsertionPoint(unsigned(IntSubsection));
+}
+
+void MCObjectStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
+  getAssembler().getOrCreateSymbolData(*Symbol);
+  Symbol->setVariableValue(AddValueSymbols(Value));
+}
+
+void MCObjectStreamer::EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) {
+  // Scan for values.
+  for (unsigned i = Inst.getNumOperands(); i--; )
+    if (Inst.getOperand(i).isExpr())
+      AddValueSymbols(Inst.getOperand(i).getExpr());
+
+  MCSectionData *SD = getCurrentSectionData();
+  SD->setHasInstructions(true);
+
+  // Now that a machine instruction has been assembled into this section, make
+  // a line entry for any .loc directive that has been seen.
+  MCLineEntry::Make(this, getCurrentSection().first);
+
+  // If this instruction doesn't need relaxation, just emit it as data.
+  MCAssembler &Assembler = getAssembler();
+  if (!Assembler.getBackend().mayNeedRelaxation(Inst)) {
+    EmitInstToData(Inst, STI);
+    return;
+  }
+
+  // Otherwise, relax and emit it as data if either:
+  // - The RelaxAll flag was passed
+  // - Bundling is enabled and this instruction is inside a bundle-locked
+  //   group. We want to emit all such instructions into the same data
+  //   fragment.
+  if (Assembler.getRelaxAll() ||
+      (Assembler.isBundlingEnabled() && SD->isBundleLocked())) {
+    MCInst Relaxed;
+    getAssembler().getBackend().relaxInstruction(Inst, Relaxed);
+    while (getAssembler().getBackend().mayNeedRelaxation(Relaxed))
+      getAssembler().getBackend().relaxInstruction(Relaxed, Relaxed);
+    EmitInstToData(Relaxed, STI);
+    return;
+  }
+
+  // Otherwise emit to a separate fragment.
+  EmitInstToFragment(Inst, STI);
 }
 
-void MCObjectStreamer::Finish() {
+void MCObjectStreamer::EmitInstToFragment(const MCInst &Inst,
+                                          const MCSubtargetInfo &STI) {
+  // Always create a new, separate fragment here, because its size can change
+  // during relaxation.
+  MCRelaxableFragment *IF = new MCRelaxableFragment(Inst, STI);
+  insert(IF);
+
+  SmallString<128> Code;
+  raw_svector_ostream VecOS(Code);
+  getAssembler().getEmitter().EncodeInstruction(Inst, VecOS, IF->getFixups(),
+                                                STI);
+  VecOS.flush();
+  IF->getContents().append(Code.begin(), Code.end());
+}
+
+#ifndef NDEBUG
+static const char *const BundlingNotImplementedMsg =
+  "Aligned bundling is not implemented for this object format";
+#endif
+
+void MCObjectStreamer::EmitBundleAlignMode(unsigned AlignPow2) {
+  llvm_unreachable(BundlingNotImplementedMsg);
+}
+
+void MCObjectStreamer::EmitBundleLock(bool AlignToEnd) {
+  llvm_unreachable(BundlingNotImplementedMsg);
+}
+
+void MCObjectStreamer::EmitBundleUnlock() {
+  llvm_unreachable(BundlingNotImplementedMsg);
+}
+
+void MCObjectStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
+                                             unsigned Column, unsigned Flags,
+                                             unsigned Isa,
+                                             unsigned Discriminator,
+                                             StringRef FileName) {
+  // In case we see two .loc directives in a row, make sure the
+  // first one gets a line entry.
+  MCLineEntry::Make(this, getCurrentSection().first);
+
+  this->MCStreamer::EmitDwarfLocDirective(FileNo, Line, Column, Flags,
+                                          Isa, Discriminator, FileName);
+}
+
+void MCObjectStreamer::EmitDwarfAdvanceLineAddr(int64_t LineDelta,
+                                                const MCSymbol *LastLabel,
+                                                const MCSymbol *Label,
+                                                unsigned PointerSize) {
+  if (!LastLabel) {
+    EmitDwarfSetLineAddr(LineDelta, Label, PointerSize);
+    return;
+  }
+  const MCExpr *AddrDelta = BuildSymbolDiff(getContext(), Label, LastLabel);
+  int64_t Res;
+  if (AddrDelta->EvaluateAsAbsolute(Res, getAssembler())) {
+    MCDwarfLineAddr::Emit(this, LineDelta, Res);
+    return;
+  }
+  AddrDelta = ForceExpAbs(AddrDelta);
+  insert(new MCDwarfLineAddrFragment(LineDelta, *AddrDelta));
+}
+
+void MCObjectStreamer::EmitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel,
+                                                 const MCSymbol *Label) {
+  const MCExpr *AddrDelta = BuildSymbolDiff(getContext(), Label, LastLabel);
+  int64_t Res;
+  if (AddrDelta->EvaluateAsAbsolute(Res, getAssembler())) {
+    MCDwarfFrameEmitter::EmitAdvanceLoc(*this, Res);
+    return;
+  }
+  AddrDelta = ForceExpAbs(AddrDelta);
+  insert(new MCDwarfCallFrameFragment(*AddrDelta));
+}
+
+void MCObjectStreamer::EmitBytes(StringRef Data) {
+  MCLineEntry::Make(this, getCurrentSection().first);
+  getOrCreateDataFragment()->getContents().append(Data.begin(), Data.end());
+}
+
+void MCObjectStreamer::EmitValueToAlignment(unsigned ByteAlignment,
+                                            int64_t Value,
+                                            unsigned ValueSize,
+                                            unsigned MaxBytesToEmit) {
+  if (MaxBytesToEmit == 0)
+    MaxBytesToEmit = ByteAlignment;
+  insert(new MCAlignFragment(ByteAlignment, Value, ValueSize, MaxBytesToEmit));
+
+  // Update the maximum alignment on the current section if necessary.
+  if (ByteAlignment > getCurrentSectionData()->getAlignment())
+    getCurrentSectionData()->setAlignment(ByteAlignment);
+}
+
+void MCObjectStreamer::EmitCodeAlignment(unsigned ByteAlignment,
+                                         unsigned MaxBytesToEmit) {
+  EmitValueToAlignment(ByteAlignment, 0, 1, MaxBytesToEmit);
+  cast<MCAlignFragment>(getCurrentFragment())->setEmitNops(true);
+}
+
+bool MCObjectStreamer::EmitValueToOffset(const MCExpr *Offset,
+                                         unsigned char Value) {
+  int64_t Res;
+  if (Offset->EvaluateAsAbsolute(Res, getAssembler())) {
+    insert(new MCOrgFragment(*Offset, Value));
+    return false;
+  }
+
+  MCSymbol *CurrentPos = getContext().CreateTempSymbol();
+  EmitLabel(CurrentPos);
+  MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
+  const MCExpr *Ref =
+    MCSymbolRefExpr::Create(CurrentPos, Variant, getContext());
+  const MCExpr *Delta =
+    MCBinaryExpr::Create(MCBinaryExpr::Sub, Offset, Ref, getContext());
+
+  if (!Delta->EvaluateAsAbsolute(Res, getAssembler()))
+    return true;
+  EmitFill(Res, Value);
+  return false;
+}
+
+// Associate GPRel32 fixup with data and resize data area
+void MCObjectStreamer::EmitGPRel32Value(const MCExpr *Value) {
+  MCDataFragment *DF = getOrCreateDataFragment();
+
+  DF->getFixups().push_back(MCFixup::Create(DF->getContents().size(), 
+                                            Value, FK_GPRel_4));
+  DF->getContents().resize(DF->getContents().size() + 4, 0);
+}
+
+// Associate GPRel32 fixup with data and resize data area
+void MCObjectStreamer::EmitGPRel64Value(const MCExpr *Value) {
+  MCDataFragment *DF = getOrCreateDataFragment();
+
+  DF->getFixups().push_back(MCFixup::Create(DF->getContents().size(), 
+                                            Value, FK_GPRel_4));
+  DF->getContents().resize(DF->getContents().size() + 8, 0);
+}
+
+void MCObjectStreamer::EmitFill(uint64_t NumBytes, uint8_t FillValue) {
+  // FIXME: A MCFillFragment would be more memory efficient but MCExpr has
+  //        problems evaluating expressions across multiple fragments.
+  getOrCreateDataFragment()->getContents().append(NumBytes, FillValue);
+}
+
+void MCObjectStreamer::EmitZeros(uint64_t NumBytes) {
+  unsigned ItemSize = getCurrentSection().first->isVirtualSection() ? 0 : 1;
+  insert(new MCFillFragment(0, ItemSize, NumBytes));
+}
+
+void MCObjectStreamer::FinishImpl() {
+  // Dump out the dwarf file & directory tables and line tables.
+  const MCSymbol *LineSectionSymbol = NULL;
+  if (!getContext().getMCLineTableSymbols().empty() ||
+      getContext().hasDwarfFiles())
+    LineSectionSymbol = MCDwarfFileTable::Emit(this);
+
+  // If we are generating dwarf for assembly source files dump out the sections.
+  if (getContext().getGenDwarfForAssembly())
+    MCGenDwarfInfo::Emit(this, LineSectionSymbol);
+
   getAssembler().Finish();
 }