#include "llvm/MC/MCObjectStreamer.h"
+#include "llvm/Support/ErrorHandling.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/MCSymbol.h"
+#include "llvm/Target/TargetAsmBackend.h"
+#include "llvm/Target/TargetAsmInfo.h"
using namespace llvm;
MCObjectStreamer::MCObjectStreamer(MCContext &Context, TargetAsmBackend &TAB,
- raw_ostream &_OS, MCCodeEmitter *_Emitter)
- : MCStreamer(Context), Assembler(new MCAssembler(Context, TAB,
- *_Emitter, _OS)),
+ raw_ostream &OS, MCCodeEmitter *Emitter_)
+ : MCStreamer(Context),
+ Assembler(new MCAssembler(Context, TAB,
+ *Emitter_, *TAB.createObjectWriter(OS),
+ OS)),
CurSectionData(0)
{
}
MCObjectStreamer::~MCObjectStreamer() {
+ delete &Assembler->getBackend();
+ delete &Assembler->getEmitter();
+ delete &Assembler->getWriter();
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::EmitValueImpl(const MCExpr *Value, unsigned Size,
+ bool isPCRel, unsigned AddrSpace) {
+ assert(AddrSpace == 0 && "Address space must be 0!");
+ MCDataFragment *DF = getOrCreateDataFragment();
+
+ // Avoid fixups when possible.
+ int64_t AbsValue;
+ if (AddValueSymbols(Value)->EvaluateAsAbsolute(AbsValue)) {
+ EmitIntValue(AbsValue, Size, AddrSpace);
+ return;
+ }
+ DF->addFixup(MCFixup::Create(DF->getContents().size(),
+ AddValueSymbols(Value),
+ MCFixup::getKindForSize(Size, isPCRel)));
+ DF->getContents().resize(DF->getContents().size() + Size, 0);
+}
+
+void MCObjectStreamer::EmitLabel(MCSymbol *Symbol) {
+ 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 MCObjectStreamer::EmitULEB128Value(const MCExpr *Value,
+ unsigned AddrSpace) {
+ int64_t IntValue;
+ if (Value->EvaluateAsAbsolute(IntValue)) {
+ EmitULEB128IntValue(IntValue, AddrSpace);
+ return;
+ }
+ new MCLEBFragment(*Value, false, getCurrentSectionData());
+}
+
+void MCObjectStreamer::EmitSLEB128Value(const MCExpr *Value,
+ unsigned AddrSpace) {
+ int64_t IntValue;
+ if (Value->EvaluateAsAbsolute(IntValue)) {
+ EmitSLEB128IntValue(IntValue, AddrSpace);
+ return;
+ }
+ new MCLEBFragment(*Value, true, getCurrentSectionData());
+}
+
+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) {
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);
}
+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());
+
+ getCurrentSectionData()->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());
+
+ // If this instruction doesn't need relaxation, just emit it as data.
+ if (!getAssembler().getBackend().MayNeedRelaxation(Inst)) {
+ EmitInstToData(Inst);
+ return;
+ }
+
+ // Otherwise, if we are relaxing everything, relax the instruction as much as
+ // possible and emit it as data.
+ if (getAssembler().getRelaxAll()) {
+ MCInst Relaxed;
+ getAssembler().getBackend().RelaxInstruction(Inst, Relaxed);
+ while (getAssembler().getBackend().MayNeedRelaxation(Relaxed))
+ getAssembler().getBackend().RelaxInstruction(Relaxed, Relaxed);
+ EmitInstToData(Relaxed);
+ return;
+ }
+
+ // Otherwise emit to a separate fragment.
+ EmitInstToFragment(Inst);
+}
+
+void MCObjectStreamer::EmitInstToFragment(const MCInst &Inst) {
+ MCInstFragment *IF = new MCInstFragment(Inst, getCurrentSectionData());
+
+ raw_svector_ostream VecOS(IF->getCode());
+ getAssembler().getEmitter().EncodeInstruction(Inst, VecOS, IF->getFixups());
+}
+
+void MCObjectStreamer::EmitDwarfAdvanceLineAddr(int64_t LineDelta,
+ const MCSymbol *LastLabel,
+ const MCSymbol *Label) {
+ if (!LastLabel) {
+ int PointerSize = getContext().getTargetAsmInfo().getPointerSize();
+ EmitDwarfSetLineAddr(LineDelta, Label, PointerSize);
+ return;
+ }
+ MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
+ const MCExpr *LabelRef =
+ MCSymbolRefExpr::Create(Label, Variant, getContext());
+ const MCExpr *LastLabelRef =
+ MCSymbolRefExpr::Create(LastLabel, Variant, getContext());
+ const MCExpr *AddrDelta =
+ MCBinaryExpr::Create(MCBinaryExpr::Sub, LabelRef, LastLabelRef,
+ getContext());
+ int64_t Res;
+ if (AddrDelta->EvaluateAsAbsolute(Res)) {
+ MCDwarfLineAddr::Emit(this, LineDelta, Res);
+ return;
+ }
+ new MCDwarfLineAddrFragment(LineDelta, *AddrDelta, getCurrentSectionData());
+}
+
+void MCObjectStreamer::EmitValueToOffset(const MCExpr *Offset,
+ unsigned char Value) {
+ new MCOrgFragment(*Offset, Value, getCurrentSectionData());
+}
+
void MCObjectStreamer::Finish() {
+ // Dump out the dwarf file & directory tables and line tables.
+ if (getContext().hasDwarfFiles())
+ MCDwarfFileTable::Emit(this);
+
getAssembler().Finish();
}
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