AArch64ELFStreamer.cpp [plain text]
#include "llvm/MC/MCELFStreamer.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/Twine.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/MCELF.h"
#include "llvm/MC/MCELFStreamer.h"
#include "llvm/MC/MCELFSymbolFlags.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCObjectStreamer.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCSectionELF.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/MC/MCValue.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ELF.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FormattedStream.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
namespace {
class AArch64ELFStreamer;
class AArch64TargetAsmStreamer : public AArch64TargetStreamer {
formatted_raw_ostream &OS;
void emitInst(uint32_t Inst) override;
public:
AArch64TargetAsmStreamer(MCStreamer &S, formatted_raw_ostream &OS);
};
AArch64TargetAsmStreamer::AArch64TargetAsmStreamer(MCStreamer &S,
formatted_raw_ostream &OS)
: AArch64TargetStreamer(S), OS(OS) {}
void AArch64TargetAsmStreamer::emitInst(uint32_t Inst) {
OS << "\t.inst\t0x" << utohexstr(Inst) << "\n";
}
class AArch64TargetELFStreamer : public AArch64TargetStreamer {
private:
AArch64ELFStreamer &getStreamer();
void emitInst(uint32_t Inst) override;
public:
AArch64TargetELFStreamer(MCStreamer &S) : AArch64TargetStreamer(S) {}
};
class AArch64ELFStreamer : public MCELFStreamer {
public:
friend class AArch64TargetELFStreamer;
AArch64ELFStreamer(MCContext &Context, MCAsmBackend &TAB, raw_ostream &OS,
MCCodeEmitter *Emitter)
: MCELFStreamer(Context, TAB, OS, Emitter), MappingSymbolCounter(0),
LastEMS(EMS_None) {}
~AArch64ELFStreamer() {}
void ChangeSection(const MCSection *Section,
const MCExpr *Subsection) override {
LastMappingSymbols[getPreviousSection().first] = LastEMS;
LastEMS = LastMappingSymbols.lookup(Section);
MCELFStreamer::ChangeSection(Section, Subsection);
}
void EmitInstruction(const MCInst &Inst,
const MCSubtargetInfo &STI) override {
EmitA64MappingSymbol();
MCELFStreamer::EmitInstruction(Inst, STI);
}
void emitInst(uint32_t Inst) {
char Buffer[4];
const bool LittleEndian = getContext().getAsmInfo()->isLittleEndian();
EmitA64MappingSymbol();
for (unsigned II = 0; II != 4; ++II) {
const unsigned I = LittleEndian ? (4 - II - 1) : II;
Buffer[4 - II - 1] = uint8_t(Inst >> I * CHAR_BIT);
}
MCELFStreamer::EmitBytes(StringRef(Buffer, 4));
}
void EmitBytes(StringRef Data) override {
EmitDataMappingSymbol();
MCELFStreamer::EmitBytes(Data);
}
void EmitValueImpl(const MCExpr *Value, unsigned Size,
const SMLoc &Loc) override {
EmitDataMappingSymbol();
MCELFStreamer::EmitValueImpl(Value, Size);
}
private:
enum ElfMappingSymbol {
EMS_None,
EMS_A64,
EMS_Data
};
void EmitDataMappingSymbol() {
if (LastEMS == EMS_Data)
return;
EmitMappingSymbol("$d");
LastEMS = EMS_Data;
}
void EmitA64MappingSymbol() {
if (LastEMS == EMS_A64)
return;
EmitMappingSymbol("$x");
LastEMS = EMS_A64;
}
void EmitMappingSymbol(StringRef Name) {
MCSymbol *Start = getContext().CreateTempSymbol();
EmitLabel(Start);
MCSymbol *Symbol = getContext().GetOrCreateSymbol(
Name + "." + Twine(MappingSymbolCounter++));
MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
MCELF::SetType(SD, ELF::STT_NOTYPE);
MCELF::SetBinding(SD, ELF::STB_LOCAL);
SD.setExternal(false);
auto Sec = getCurrentSection().first;
assert(Sec && "need a section");
Symbol->setSection(*Sec);
const MCExpr *Value = MCSymbolRefExpr::Create(Start, getContext());
Symbol->setVariableValue(Value);
}
int64_t MappingSymbolCounter;
DenseMap<const MCSection *, ElfMappingSymbol> LastMappingSymbols;
ElfMappingSymbol LastEMS;
};
}
AArch64ELFStreamer &AArch64TargetELFStreamer::getStreamer() {
return static_cast<AArch64ELFStreamer &>(Streamer);
}
void AArch64TargetELFStreamer::emitInst(uint32_t Inst) {
getStreamer().emitInst(Inst);
}
namespace llvm {
MCStreamer *
createAArch64MCAsmStreamer(MCContext &Ctx, formatted_raw_ostream &OS,
bool isVerboseAsm, bool useDwarfDirectory,
MCInstPrinter *InstPrint, MCCodeEmitter *CE,
MCAsmBackend *TAB, bool ShowInst) {
MCStreamer *S = llvm::createAsmStreamer(
Ctx, OS, isVerboseAsm, useDwarfDirectory, InstPrint, CE, TAB, ShowInst);
new AArch64TargetAsmStreamer(*S, OS);
return S;
}
MCELFStreamer *createAArch64ELFStreamer(MCContext &Context, MCAsmBackend &TAB,
raw_ostream &OS, MCCodeEmitter *Emitter,
bool RelaxAll) {
AArch64ELFStreamer *S = new AArch64ELFStreamer(Context, TAB, OS, Emitter);
new AArch64TargetELFStreamer(*S);
if (RelaxAll)
S->getAssembler().setRelaxAll(true);
return S;
}
}