X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FMC%2FMCObjectStreamer.cpp;h=d82dd15df2bc0871dbff739648004bf1a4001a4f;hb=19696daa2159e059b9a15cda222e97d2b91b279d;hp=8635aac00302ba3384cfcc72088f6f01e5d230d7;hpb=672b93a3324cc1da6d374eed4c75c050a9cad7be;p=oota-llvm.git

diff --git a/lib/MC/MCObjectStreamer.cpp b/lib/MC/MCObjectStreamer.cpp
index 8635aac0030..d82dd15df2b 100644
--- a/lib/MC/MCObjectStreamer.cpp
+++ b/lib/MC/MCObjectStreamer.cpp
@@ -7,35 +7,29 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/MC/MCAsmInfo.h"
 #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/MC/MCObjectWriter.h"
+#include "llvm/MC/MCSection.h"
 #include "llvm/MC/MCSymbol.h"
-#include "llvm/Target/TargetAsmBackend.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/TargetRegistry.h"
 using namespace llvm;
 
-MCObjectStreamer::MCObjectStreamer(MCContext &Context, TargetAsmBackend &TAB,
-                                   raw_ostream &OS, MCCodeEmitter *Emitter_)
-  : MCStreamer(Context),
-    Assembler(new MCAssembler(Context, TAB,
-                              *Emitter_, *TAB.createObjectWriter(OS),
-                              OS)),
-    CurSectionData(0)
-{
-}
-
-MCObjectStreamer::MCObjectStreamer(MCContext &Context, TargetAsmBackend &TAB,
-                                   raw_ostream &OS, MCCodeEmitter *Emitter_,
-                                   MCAssembler *_Assembler)
-  : MCStreamer(Context), Assembler(_Assembler), CurSectionData(0)
-{
-}
+MCObjectStreamer::MCObjectStreamer(MCContext &Context, MCAsmBackend &TAB,
+                                   raw_pwrite_stream &OS,
+                                   MCCodeEmitter *Emitter_)
+    : MCStreamer(Context),
+      Assembler(new MCAssembler(Context, TAB, *Emitter_,
+                                *TAB.createObjectWriter(OS), OS)),
+      CurSectionData(nullptr), EmitEHFrame(true), EmitDebugFrame(false) {}
 
 MCObjectStreamer::~MCObjectStreamer() {
   delete &Assembler->getBackend();
@@ -44,80 +38,121 @@ MCObjectStreamer::~MCObjectStreamer() {
   delete Assembler;
 }
 
+void MCObjectStreamer::flushPendingLabels(MCFragment *F, uint64_t FOffset) {
+  if (PendingLabels.size()) {
+    if (!F) {
+      F = new MCDataFragment();
+      CurSectionData->getFragmentList().insert(CurInsertionPoint, F);
+      F->setParent(CurSectionData);
+    }
+    for (MCSymbolData *SD : PendingLabels) {
+      SD->setFragment(F);
+      SD->setOffset(FOffset);
+    }
+    PendingLabels.clear();
+  }
+}
+
+void MCObjectStreamer::reset() {
+  if (Assembler)
+    Assembler->reset();
+  CurSectionData = nullptr;
+  CurInsertionPoint = MCSectionData::iterator();
+  EmitEHFrame = true;
+  EmitDebugFrame = false;
+  PendingLabels.clear();
+  MCStreamer::reset();
+}
+
+void MCObjectStreamer::EmitFrames(MCAsmBackend *MAB) {
+  if (!getNumFrameInfos())
+    return;
+
+  if (EmitEHFrame)
+    MCDwarfFrameEmitter::Emit(*this, MAB, true);
+
+  if (EmitDebugFrame)
+    MCDwarfFrameEmitter::Emit(*this, MAB, false);
+}
+
 MCFragment *MCObjectStreamer::getCurrentFragment() const {
   assert(getCurrentSectionData() && "No current section!");
 
-  if (!getCurrentSectionData()->empty())
-    return &getCurrentSectionData()->getFragmentList().back();
+  if (CurInsertionPoint != getCurrentSectionData()->getFragmentList().begin())
+    return std::prev(CurInsertionPoint);
 
-  return 0;
+  return nullptr;
 }
 
-MCDataFragment *MCObjectStreamer::getOrCreateDataFragment() const {
+MCDataFragment *MCObjectStreamer::getOrCreateDataFragment() {
   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() && !Assembler->getRelaxAll() &&
+             F->hasInstructions())) {
+    F = new MCDataFragment();
+    insert(F);
+  }
   return F;
 }
 
-const MCExpr *MCObjectStreamer::AddValueSymbols(const MCExpr *Value) {
-  switch (Value->getKind()) {
-  case MCExpr::Target:
-    cast<MCTargetExpr>(Value)->AddValueSymbols(Assembler);
-    break;
-
-  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;
-  }
+void MCObjectStreamer::visitUsedSymbol(const MCSymbol &Sym) {
+  Assembler->getOrCreateSymbolData(Sym);
+}
 
-  return Value;
+void MCObjectStreamer::EmitCFISections(bool EH, bool Debug) {
+  MCStreamer::EmitCFISections(EH, Debug);
+  EmitEHFrame = EH;
+  EmitDebugFrame = Debug;
 }
 
 void MCObjectStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size,
-                                     unsigned AddrSpace) {
-  assert(AddrSpace == 0 && "Address space must be 0!");
+                                     const SMLoc &Loc) {
+  MCStreamer::EmitValueImpl(Value, Size, Loc);
   MCDataFragment *DF = getOrCreateDataFragment();
 
+  MCLineEntry::Make(this, getCurrentSection().first);
+
   // Avoid fixups when possible.
   int64_t AbsValue;
-  if (AddValueSymbols(Value)->EvaluateAsAbsolute(AbsValue, getAssembler())) {
-    EmitIntValue(AbsValue, Size, AddrSpace);
+  if (Value->EvaluateAsAbsolute(AbsValue, getAssembler())) {
+    EmitIntValue(AbsValue, Size);
     return;
   }
-  DF->addFixup(MCFixup::Create(DF->getContents().size(),
-                               Value,
-                               MCFixup::getKindForSize(Size, false)));
+  DF->getFixups().push_back(
+      MCFixup::create(DF->getContents().size(), Value,
+                      MCFixup::getKindForSize(Size, false), Loc));
   DF->getContents().resize(DF->getContents().size() + Size, 0);
 }
 
+void MCObjectStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) {
+  // We need to create a local symbol to avoid relocations.
+  Frame.Begin = getContext().createTempSymbol();
+  EmitLabel(Frame.Begin);
+}
+
+void MCObjectStreamer::EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) {
+  Frame.End = getContext().createTempSymbol();
+  EmitLabel(Frame.End);
+}
+
 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());
+
+  // If there is a current fragment, mark the symbol as pointing into it.
+  // Otherwise queue the label and set its fragment pointer when we emit the
+  // next fragment.
+  auto *F = dyn_cast_or_null<MCDataFragment>(getCurrentFragment());
+  if (F && !(getAssembler().isBundlingEnabled() &&
+             getAssembler().getRelaxAll())) {
+    SD.setFragment(F);
+    SD.setOffset(F->getContents().size());
+  } else {
+    PendingLabels.push_back(&SD);
+  }
 }
 
 void MCObjectStreamer::EmitULEB128Value(const MCExpr *Value) {
@@ -126,8 +161,7 @@ void MCObjectStreamer::EmitULEB128Value(const MCExpr *Value) {
     EmitULEB128IntValue(IntValue);
     return;
   }
-  Value = ForceExpAbs(Value);
-  new MCLEBFragment(*Value, false, getCurrentSectionData());
+  insert(new MCLEBFragment(*Value, false));
 }
 
 void MCObjectStreamer::EmitSLEB128Value(const MCExpr *Value) {
@@ -136,8 +170,7 @@ void MCObjectStreamer::EmitSLEB128Value(const MCExpr *Value) {
     EmitSLEB128IntValue(IntValue);
     return;
   }
-  Value = ForceExpAbs(Value);
-  new MCLEBFragment(*Value, true, getCurrentSectionData());
+  insert(new MCLEBFragment(*Value, true));
 }
 
 void MCObjectStreamer::EmitWeakReference(MCSymbol *Alias,
@@ -145,53 +178,141 @@ void MCObjectStreamer::EmitWeakReference(MCSymbol *Alias,
   report_fatal_error("This file format doesn't support weak aliases.");
 }
 
-void MCObjectStreamer::ChangeSection(const MCSection *Section) {
+void MCObjectStreamer::ChangeSection(const MCSection *Section,
+                                     const MCExpr *Subsection) {
+  changeSectionImpl(Section, Subsection);
+}
+
+bool MCObjectStreamer::changeSectionImpl(const MCSection *Section,
+                                         const MCExpr *Subsection) {
   assert(Section && "Cannot switch to a null section!");
+  flushPendingLabels(nullptr);
+
+  bool Created;
+  CurSectionData = &getAssembler().getOrCreateSectionData(*Section, &Created);
+
+  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));
+  return Created;
+}
 
-  CurSectionData = &getAssembler().getOrCreateSectionData(*Section);
+void MCObjectStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
+  getAssembler().getOrCreateSymbolData(*Symbol);
+  MCStreamer::EmitAssignment(Symbol, Value);
 }
 
-void MCObjectStreamer::EmitInstruction(const MCInst &Inst) {
-  // Scan for values.
-  for (unsigned i = Inst.getNumOperands(); i--; )
-    if (Inst.getOperand(i).isExpr())
-      AddValueSymbols(Inst.getOperand(i).getExpr());
+void MCObjectStreamer::EmitInstruction(const MCInst &Inst,
+                                       const MCSubtargetInfo &STI) {
+  MCStreamer::EmitInstruction(Inst, STI);
 
-  getCurrentSectionData()->setHasInstructions(true);
+  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());
+  MCLineEntry::Make(this, getCurrentSection().first);
 
   // If this instruction doesn't need relaxation, just emit it as data.
-  if (!getAssembler().getBackend().MayNeedRelaxation(Inst)) {
-    EmitInstToData(Inst);
+  MCAssembler &Assembler = getAssembler();
+  if (!Assembler.getBackend().mayNeedRelaxation(Inst)) {
+    EmitInstToData(Inst, STI);
     return;
   }
 
-  // Otherwise, if we are relaxing everything, relax the instruction as much as
-  // possible and emit it as data.
-  if (getAssembler().getRelaxAll()) {
+  // 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);
+    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);
+  EmitInstToFragment(Inst, STI);
 }
 
-void MCObjectStreamer::EmitInstToFragment(const MCInst &Inst) {
-  MCInstFragment *IF = new MCInstFragment(Inst, getCurrentSectionData());
+void MCObjectStreamer::EmitInstToFragment(const MCInst &Inst,
+                                          const MCSubtargetInfo &STI) {
+  if (getAssembler().getRelaxAll() && getAssembler().isBundlingEnabled())
+    llvm_unreachable("All instructions should have already been relaxed");
+
+  // 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());
+  getAssembler().getEmitter().encodeInstruction(Inst, VecOS, IF->getFixups(),
+                                                STI);
   VecOS.flush();
-  IF->getCode().append(Code.begin(), Code.end());
+  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);
+}
+
+static const MCExpr *buildSymbolDiff(MCObjectStreamer &OS, const MCSymbol *A,
+                                     const MCSymbol *B) {
+  MCContext &Context = OS.getContext();
+  MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
+  const MCExpr *ARef = MCSymbolRefExpr::Create(A, Variant, Context);
+  const MCExpr *BRef = MCSymbolRefExpr::Create(B, Variant, Context);
+  const MCExpr *AddrDelta =
+      MCBinaryExpr::Create(MCBinaryExpr::Sub, ARef, BRef, Context);
+  return AddrDelta;
+}
+
+static void emitDwarfSetLineAddr(MCObjectStreamer &OS, int64_t LineDelta,
+                                 const MCSymbol *Label, int PointerSize) {
+  // emit the sequence to set the address
+  OS.EmitIntValue(dwarf::DW_LNS_extended_op, 1);
+  OS.EmitULEB128IntValue(PointerSize + 1);
+  OS.EmitIntValue(dwarf::DW_LNE_set_address, 1);
+  OS.EmitSymbolValue(Label, PointerSize);
+
+  // emit the sequence for the LineDelta (from 1) and a zero address delta.
+  MCDwarfLineAddr::Emit(&OS, LineDelta, 0);
 }
 
 void MCObjectStreamer::EmitDwarfAdvanceLineAddr(int64_t LineDelta,
@@ -199,40 +320,62 @@ void MCObjectStreamer::EmitDwarfAdvanceLineAddr(int64_t LineDelta,
                                                 const MCSymbol *Label,
                                                 unsigned PointerSize) {
   if (!LastLabel) {
-    EmitDwarfSetLineAddr(LineDelta, Label, PointerSize);
+    emitDwarfSetLineAddr(*this, LineDelta, Label, PointerSize);
     return;
   }
-  const MCExpr *AddrDelta = BuildSymbolDiff(getContext(), Label, LastLabel);
+  const MCExpr *AddrDelta = buildSymbolDiff(*this, Label, LastLabel);
   int64_t Res;
   if (AddrDelta->EvaluateAsAbsolute(Res, getAssembler())) {
     MCDwarfLineAddr::Emit(this, LineDelta, Res);
     return;
   }
-  AddrDelta = ForceExpAbs(AddrDelta);
-  new MCDwarfLineAddrFragment(LineDelta, *AddrDelta, getCurrentSectionData());
+  insert(new MCDwarfLineAddrFragment(LineDelta, *AddrDelta));
 }
 
 void MCObjectStreamer::EmitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel,
                                                  const MCSymbol *Label) {
-  const MCExpr *AddrDelta = BuildSymbolDiff(getContext(), Label, LastLabel);
+  const MCExpr *AddrDelta = buildSymbolDiff(*this, Label, LastLabel);
   int64_t Res;
   if (AddrDelta->EvaluateAsAbsolute(Res, getAssembler())) {
     MCDwarfFrameEmitter::EmitAdvanceLoc(*this, Res);
     return;
   }
-  AddrDelta = ForceExpAbs(AddrDelta);
-  new MCDwarfCallFrameFragment(*AddrDelta, getCurrentSectionData());
+  insert(new MCDwarfCallFrameFragment(*AddrDelta));
+}
+
+void MCObjectStreamer::EmitBytes(StringRef Data) {
+  MCLineEntry::Make(this, getCurrentSection().first);
+  getOrCreateDataFragment()->getContents().append(Data.begin(), Data.end());
 }
 
-void MCObjectStreamer::EmitValueToOffset(const MCExpr *Offset,
-                                        unsigned char Value) {
+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())) {
-    new MCOrgFragment(*Offset, Value, getCurrentSectionData());
-    return;
+    insert(new MCOrgFragment(*Offset, Value));
+    return false;
   }
 
-  MCSymbol *CurrentPos = getContext().CreateTempSymbol();
+  MCSymbol *CurrentPos = getContext().createTempSymbol();
   EmitLabel(CurrentPos);
   MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
   const MCExpr *Ref =
@@ -241,14 +384,50 @@ void MCObjectStreamer::EmitValueToOffset(const MCExpr *Offset,
     MCBinaryExpr::Create(MCBinaryExpr::Sub, Offset, Ref, getContext());
 
   if (!Delta->EvaluateAsAbsolute(Res, getAssembler()))
-    report_fatal_error("expected assembly-time absolute expression");
-  EmitFill(Res, Value, 0);
+    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);
 }
 
-void MCObjectStreamer::Finish() {
+// 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) {
+  const MCSection *Sec = getCurrentSection().first;
+  assert(Sec && "need a section");
+  unsigned ItemSize = Sec->isVirtualSection() ? 0 : 1;
+  insert(new MCFillFragment(0, ItemSize, NumBytes));
+}
+
+void MCObjectStreamer::FinishImpl() {
+  // If we are generating dwarf for assembly source files dump out the sections.
+  if (getContext().getGenDwarfForAssembly())
+    MCGenDwarfInfo::Emit(this);
+
   // Dump out the dwarf file & directory tables and line tables.
-  if (getContext().hasDwarfFiles())
-    MCDwarfFileTable::Emit(this);
+  MCDwarfLineTable::Emit(this);
 
+  flushPendingLabels(nullptr);
   getAssembler().Finish();
 }