#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/MC/MCAsmBackend.h"
+#include "llvm/MC/MCAsmLayout.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ELF.h"
#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
+bool MCELFStreamer::isBundleLocked() const {
+ return getCurrentSectionOnly()->isBundleLocked();
+}
+
MCELFStreamer::~MCELFStreamer() {
}
+void MCELFStreamer::mergeFragment(MCDataFragment *DF,
+ MCEncodedFragmentWithFixups *EF) {
+ MCAssembler &Assembler = getAssembler();
+
+ if (Assembler.isBundlingEnabled() && Assembler.getRelaxAll()) {
+ uint64_t FSize = EF->getContents().size();
+
+ if (FSize > Assembler.getBundleAlignSize())
+ report_fatal_error("Fragment can't be larger than a bundle size");
+
+ uint64_t RequiredBundlePadding = computeBundlePadding(
+ Assembler, EF, DF->getContents().size(), FSize);
+
+ if (RequiredBundlePadding > UINT8_MAX)
+ report_fatal_error("Padding cannot exceed 255 bytes");
+
+ if (RequiredBundlePadding > 0) {
+ SmallString<256> Code;
+ raw_svector_ostream VecOS(Code);
+ MCObjectWriter *OW = Assembler.getBackend().createObjectWriter(VecOS);
+
+ EF->setBundlePadding(static_cast<uint8_t>(RequiredBundlePadding));
+
+ Assembler.writeFragmentPadding(*EF, FSize, OW);
+ VecOS.flush();
+ delete OW;
+
+ DF->getContents().append(Code.begin(), Code.end());
+ }
+ }
+
+ flushPendingLabels(DF, DF->getContents().size());
+
+ for (unsigned i = 0, e = EF->getFixups().size(); i != e; ++i) {
+ EF->getFixups()[i].setOffset(EF->getFixups()[i].getOffset() +
+ DF->getContents().size());
+ DF->getFixups().push_back(EF->getFixups()[i]);
+ }
+ DF->setHasInstructions(true);
+ DF->getContents().append(EF->getContents().begin(), EF->getContents().end());
+}
+
void MCELFStreamer::InitSections(bool NoExecStack) {
// This emulates the same behavior of GNU as. This makes it easier
// to compare the output as the major sections are in the same order.
const MCSectionELF &Section =
static_cast<const MCSectionELF&>(Symbol->getSection());
- MCSymbolData &SD = getAssembler().getSymbolData(*Symbol);
if (Section.getFlags() & ELF::SHF_TLS)
- MCELF::SetType(SD, ELF::STT_TLS);
+ MCELF::SetType(*Symbol, ELF::STT_TLS);
}
void MCELFStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
llvm_unreachable("invalid assembler flag!");
}
-void MCELFStreamer::ChangeSection(const MCSection *Section,
+// If bundle aligment is used and there are any instructions in the section, it
+// needs to be aligned to at least the bundle size.
+static void setSectionAlignmentForBundling(const MCAssembler &Assembler,
+ MCSection *Section) {
+ if (Section && Assembler.isBundlingEnabled() && Section->hasInstructions() &&
+ Section->getAlignment() < Assembler.getBundleAlignSize())
+ Section->setAlignment(Assembler.getBundleAlignSize());
+}
+
+void MCELFStreamer::ChangeSection(MCSection *Section,
const MCExpr *Subsection) {
- MCSectionData *CurSection = getCurrentSectionData();
- if (CurSection && CurSection->isBundleLocked())
+ MCSection *CurSection = getCurrentSectionOnly();
+ if (CurSection && isBundleLocked())
report_fatal_error("Unterminated .bundle_lock when changing a section");
MCAssembler &Asm = getAssembler();
+ // Ensure the previous section gets aligned if necessary.
+ setSectionAlignmentForBundling(Asm, CurSection);
auto *SectionELF = static_cast<const MCSectionELF *>(Section);
const MCSymbol *Grp = SectionELF->getGroup();
if (Grp)
- Asm.getOrCreateSymbolData(*Grp);
+ Asm.registerSymbol(*Grp);
this->MCObjectStreamer::ChangeSection(Section, Subsection);
- MCSymbol *SectionSymbol = getContext().getOrCreateSectionSymbol(*SectionELF);
- if (SectionSymbol->isUndefined()) {
- EmitLabel(SectionSymbol);
- MCELF::SetType(Asm.getSymbolData(*SectionSymbol), ELF::STT_SECTION);
+ MCContext &Ctx = getContext();
+ MCSymbol *Begin = Section->getBeginSymbol();
+ if (!Begin) {
+ Begin = Ctx.getOrCreateSectionSymbol(*SectionELF);
+ Section->setBeginSymbol(Begin);
+ }
+ if (Begin->isUndefined()) {
+ Asm.registerSymbol(*Begin);
+ MCELF::SetType(*Begin, ELF::STT_SECTION);
}
}
void MCELFStreamer::EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {
- getAssembler().getOrCreateSymbolData(*Symbol);
+ getAssembler().registerSymbol(*Symbol);
const MCExpr *Value = MCSymbolRefExpr::Create(
Symbol, MCSymbolRefExpr::VK_WEAKREF, getContext());
Alias->setVariableValue(Value);
// If neither T1 < T2 nor T2 < T1 according to this ordering, use T2 (the user
// provided type).
static unsigned CombineSymbolTypes(unsigned T1, unsigned T2) {
- unsigned TypeOrdering[] = {ELF::STT_NOTYPE, ELF::STT_OBJECT, ELF::STT_FUNC,
- ELF::STT_GNU_IFUNC, ELF::STT_TLS};
- for (unsigned i = 0; i != array_lengthof(TypeOrdering); ++i) {
- if (T1 == TypeOrdering[i])
+ for (unsigned Type : {ELF::STT_NOTYPE, ELF::STT_OBJECT, ELF::STT_FUNC,
+ ELF::STT_GNU_IFUNC, ELF::STT_TLS}) {
+ if (T1 == Type)
return T2;
- if (T2 == TypeOrdering[i])
+ if (T2 == Type)
return T1;
}
// important for matching the string table that 'as' generates.
IndirectSymbolData ISD;
ISD.Symbol = Symbol;
- ISD.SectionData = getCurrentSectionData();
+ ISD.Section = getCurrentSectionOnly();
getAssembler().getIndirectSymbols().push_back(ISD);
return true;
}
// Adding a symbol attribute always introduces the symbol, note that an
- // important side effect of calling getOrCreateSymbolData here is to register
+ // important side effect of calling registerSymbol here is to register
// the symbol with the assembler.
- MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
+ getAssembler().registerSymbol(*Symbol);
+ MCSymbolData &SD = Symbol->getData();
// The implementation of symbol attributes is designed to match 'as', but it
// leaves much to desired. It doesn't really make sense to arbitrarily add and
return false;
case MCSA_NoDeadStrip:
- case MCSA_ELF_TypeGnuUniqueObject:
// Ignore for now.
break;
+ case MCSA_ELF_TypeGnuUniqueObject:
+ MCELF::SetType(
+ *Symbol, CombineSymbolTypes(MCELF::GetType(*Symbol), ELF::STT_OBJECT));
+ MCELF::SetBinding(*Symbol, ELF::STB_GNU_UNIQUE);
+ SD.setExternal(true);
+ BindingExplicitlySet.insert(Symbol);
+ break;
+
case MCSA_Global:
- MCELF::SetBinding(SD, ELF::STB_GLOBAL);
+ MCELF::SetBinding(*Symbol, ELF::STB_GLOBAL);
SD.setExternal(true);
BindingExplicitlySet.insert(Symbol);
break;
case MCSA_WeakReference:
case MCSA_Weak:
- MCELF::SetBinding(SD, ELF::STB_WEAK);
+ MCELF::SetBinding(*Symbol, ELF::STB_WEAK);
SD.setExternal(true);
BindingExplicitlySet.insert(Symbol);
break;
case MCSA_Local:
- MCELF::SetBinding(SD, ELF::STB_LOCAL);
+ MCELF::SetBinding(*Symbol, ELF::STB_LOCAL);
SD.setExternal(false);
BindingExplicitlySet.insert(Symbol);
break;
case MCSA_ELF_TypeFunction:
- MCELF::SetType(SD, CombineSymbolTypes(MCELF::GetType(SD),
- ELF::STT_FUNC));
+ MCELF::SetType(*Symbol,
+ CombineSymbolTypes(MCELF::GetType(*Symbol), ELF::STT_FUNC));
break;
case MCSA_ELF_TypeIndFunction:
- MCELF::SetType(SD, CombineSymbolTypes(MCELF::GetType(SD),
- ELF::STT_GNU_IFUNC));
+ MCELF::SetType(*Symbol, CombineSymbolTypes(MCELF::GetType(*Symbol),
+ ELF::STT_GNU_IFUNC));
break;
case MCSA_ELF_TypeObject:
- MCELF::SetType(SD, CombineSymbolTypes(MCELF::GetType(SD),
- ELF::STT_OBJECT));
+ MCELF::SetType(
+ *Symbol, CombineSymbolTypes(MCELF::GetType(*Symbol), ELF::STT_OBJECT));
break;
case MCSA_ELF_TypeTLS:
- MCELF::SetType(SD, CombineSymbolTypes(MCELF::GetType(SD),
- ELF::STT_TLS));
+ MCELF::SetType(*Symbol,
+ CombineSymbolTypes(MCELF::GetType(*Symbol), ELF::STT_TLS));
break;
case MCSA_ELF_TypeCommon:
// TODO: Emit these as a common symbol.
- MCELF::SetType(SD, CombineSymbolTypes(MCELF::GetType(SD),
- ELF::STT_OBJECT));
+ MCELF::SetType(
+ *Symbol, CombineSymbolTypes(MCELF::GetType(*Symbol), ELF::STT_OBJECT));
break;
case MCSA_ELF_TypeNoType:
- MCELF::SetType(SD, CombineSymbolTypes(MCELF::GetType(SD),
- ELF::STT_NOTYPE));
+ MCELF::SetType(
+ *Symbol, CombineSymbolTypes(MCELF::GetType(*Symbol), ELF::STT_NOTYPE));
break;
case MCSA_Protected:
- MCELF::SetVisibility(SD, ELF::STV_PROTECTED);
+ MCELF::SetVisibility(*Symbol, ELF::STV_PROTECTED);
break;
case MCSA_Hidden:
- MCELF::SetVisibility(SD, ELF::STV_HIDDEN);
+ MCELF::SetVisibility(*Symbol, ELF::STV_HIDDEN);
break;
case MCSA_Internal:
- MCELF::SetVisibility(SD, ELF::STV_INTERNAL);
+ MCELF::SetVisibility(*Symbol, ELF::STV_INTERNAL);
break;
}
}
void MCELFStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
- unsigned ByteAlignment) {
- MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
+ unsigned ByteAlignment) {
+ getAssembler().registerSymbol(*Symbol);
+ MCSymbolData &SD = Symbol->getData();
if (!BindingExplicitlySet.count(Symbol)) {
- MCELF::SetBinding(SD, ELF::STB_GLOBAL);
+ MCELF::SetBinding(*Symbol, ELF::STB_GLOBAL);
SD.setExternal(true);
}
- MCELF::SetType(SD, ELF::STT_OBJECT);
+ MCELF::SetType(*Symbol, ELF::STT_OBJECT);
- if (MCELF::GetBinding(SD) == ELF_STB_Local) {
- const MCSection *Section = getAssembler().getContext().getELFSection(".bss",
- ELF::SHT_NOBITS,
- ELF::SHF_WRITE |
- ELF::SHF_ALLOC,
- SectionKind::getBSS());
+ if (MCELF::GetBinding(*Symbol) == ELF_STB_Local) {
+ MCSection *Section = getAssembler().getContext().getELFSection(
+ ".bss", ELF::SHT_NOBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
AssignSection(Symbol, Section);
- struct LocalCommon L = {&SD, Size, ByteAlignment};
+ struct LocalCommon L = {Symbol, Size, ByteAlignment};
LocalCommons.push_back(L);
} else {
- SD.setCommon(Size, ByteAlignment);
+ Symbol->setCommon(Size, ByteAlignment);
}
- SD.setSize(MCConstantExpr::Create(Size, getContext()));
+ Symbol->setSize(MCConstantExpr::Create(Size, getContext()));
}
void MCELFStreamer::EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {
- MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
- SD.setSize(Value);
+ Symbol->setSize(Value);
}
void MCELFStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
unsigned ByteAlignment) {
// FIXME: Should this be caught and done earlier?
- MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
- MCELF::SetBinding(SD, ELF::STB_LOCAL);
+ getAssembler().registerSymbol(*Symbol);
+ MCSymbolData &SD = Symbol->getData();
+ MCELF::SetBinding(*Symbol, ELF::STB_LOCAL);
SD.setExternal(false);
BindingExplicitlySet.insert(Symbol);
EmitCommonSymbol(Symbol, Size, ByteAlignment);
void MCELFStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size,
const SMLoc &Loc) {
- if (getCurrentSectionData()->isBundleLocked())
+ if (isBundleLocked())
report_fatal_error("Emitting values inside a locked bundle is forbidden");
fixSymbolsInTLSFixups(Value);
MCObjectStreamer::EmitValueImpl(Value, Size, Loc);
int64_t Value,
unsigned ValueSize,
unsigned MaxBytesToEmit) {
- if (getCurrentSectionData()->isBundleLocked())
+ if (isBundleLocked())
report_fatal_error("Emitting values inside a locked bundle is forbidden");
MCObjectStreamer::EmitValueToAlignment(ByteAlignment, Value,
ValueSize, MaxBytesToEmit);
}
void MCELFStreamer::EmitIdent(StringRef IdentString) {
- const MCSection *Comment = getAssembler().getContext().getELFSection(
- ".comment", ELF::SHT_PROGBITS, ELF::SHF_MERGE | ELF::SHF_STRINGS,
- SectionKind::getReadOnly(), 1, "");
+ MCSection *Comment = getAssembler().getContext().getELFSection(
+ ".comment", ELF::SHT_PROGBITS, ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, "");
PushSection();
SwitchSection(Comment);
if (!SeenIdent) {
case MCSymbolRefExpr::VK_PPC_TLSLD:
break;
}
- MCSymbolData &SD = getAssembler().getOrCreateSymbolData(symRef.getSymbol());
- MCELF::SetType(SD, ELF::STT_TLS);
+ getAssembler().registerSymbol(symRef.getSymbol());
+ MCELF::SetType(symRef.getSymbol(), ELF::STT_TLS);
break;
}
SmallVector<MCFixup, 4> Fixups;
SmallString<256> Code;
raw_svector_ostream VecOS(Code);
- Assembler.getEmitter().EncodeInstruction(Inst, VecOS, Fixups, STI);
+ Assembler.getEmitter().encodeInstruction(Inst, VecOS, Fixups, STI);
VecOS.flush();
for (unsigned i = 0, e = Fixups.size(); i != e; ++i)
MCDataFragment *DF;
if (Assembler.isBundlingEnabled()) {
- MCSectionData *SD = getCurrentSectionData();
- if (SD->isBundleLocked() && !SD->isBundleGroupBeforeFirstInst())
+ MCSection &Sec = *getCurrentSectionOnly();
+ if (Assembler.getRelaxAll() && isBundleLocked())
+ // If the -mc-relax-all flag is used and we are bundle-locked, we re-use
+ // the current bundle group.
+ DF = BundleGroups.back();
+ else if (Assembler.getRelaxAll() && !isBundleLocked())
+ // When not in a bundle-locked group and the -mc-relax-all flag is used,
+ // we create a new temporary fragment which will be later merged into
+ // the current fragment.
+ DF = new MCDataFragment();
+ else if (isBundleLocked() && !Sec.isBundleGroupBeforeFirstInst())
// If we are bundle-locked, we re-use the current fragment.
// The bundle-locking directive ensures this is a new data fragment.
DF = cast<MCDataFragment>(getCurrentFragment());
- else if (!SD->isBundleLocked() && Fixups.size() == 0) {
+ else if (!isBundleLocked() && Fixups.size() == 0) {
// Optimize memory usage by emitting the instruction to a
// MCCompactEncodedInstFragment when not in a bundle-locked group and
// there are no fixups registered.
DF = new MCDataFragment();
insert(DF);
}
- if (SD->getBundleLockState() == MCSectionData::BundleLockedAlignToEnd) {
+ if (Sec.getBundleLockState() == MCSection::BundleLockedAlignToEnd) {
// If this fragment is for a group marked "align_to_end", set a flag
// in the fragment. This can happen after the fragment has already been
// created if there are nested bundle_align groups and an inner one
// We're now emitting an instruction in a bundle group, so this flag has
// to be turned off.
- SD->setBundleGroupBeforeFirstInst(false);
+ Sec.setBundleGroupBeforeFirstInst(false);
} else {
DF = getOrCreateDataFragment();
}
}
DF->setHasInstructions(true);
DF->getContents().append(Code.begin(), Code.end());
+
+ if (Assembler.isBundlingEnabled() && Assembler.getRelaxAll()) {
+ if (!isBundleLocked()) {
+ mergeFragment(getOrCreateDataFragment(), DF);
+ delete DF;
+ }
+ }
}
void MCELFStreamer::EmitBundleAlignMode(unsigned AlignPow2) {
}
void MCELFStreamer::EmitBundleLock(bool AlignToEnd) {
- MCSectionData *SD = getCurrentSectionData();
+ MCSection &Sec = *getCurrentSectionOnly();
// Sanity checks
//
if (!getAssembler().isBundlingEnabled())
report_fatal_error(".bundle_lock forbidden when bundling is disabled");
- if (!SD->isBundleLocked())
- SD->setBundleGroupBeforeFirstInst(true);
+ if (!isBundleLocked())
+ Sec.setBundleGroupBeforeFirstInst(true);
- SD->setBundleLockState(AlignToEnd ? MCSectionData::BundleLockedAlignToEnd :
- MCSectionData::BundleLocked);
+ if (getAssembler().getRelaxAll() && !isBundleLocked()) {
+ // TODO: drop the lock state and set directly in the fragment
+ MCDataFragment *DF = new MCDataFragment();
+ BundleGroups.push_back(DF);
+ }
+
+ Sec.setBundleLockState(AlignToEnd ? MCSection::BundleLockedAlignToEnd
+ : MCSection::BundleLocked);
}
void MCELFStreamer::EmitBundleUnlock() {
- MCSectionData *SD = getCurrentSectionData();
+ MCSection &Sec = *getCurrentSectionOnly();
// Sanity checks
if (!getAssembler().isBundlingEnabled())
report_fatal_error(".bundle_unlock forbidden when bundling is disabled");
- else if (!SD->isBundleLocked())
+ else if (!isBundleLocked())
report_fatal_error(".bundle_unlock without matching lock");
- else if (SD->isBundleGroupBeforeFirstInst())
+ else if (Sec.isBundleGroupBeforeFirstInst())
report_fatal_error("Empty bundle-locked group is forbidden");
- SD->setBundleLockState(MCSectionData::NotBundleLocked);
+ // When the -mc-relax-all flag is used, we emit instructions to fragments
+ // stored on a stack. When the bundle unlock is emited, we pop a fragment
+ // from the stack a merge it to the one below.
+ if (getAssembler().getRelaxAll()) {
+ assert(!BundleGroups.empty() && "There are no bundle groups");
+ MCDataFragment *DF = BundleGroups.back();
+
+ // FIXME: Use BundleGroups to track the lock state instead.
+ Sec.setBundleLockState(MCSection::NotBundleLocked);
+
+ // FIXME: Use more separate fragments for nested groups.
+ if (!isBundleLocked()) {
+ mergeFragment(getOrCreateDataFragment(), DF);
+ BundleGroups.pop_back();
+ delete DF;
+ }
+
+ if (Sec.getBundleLockState() != MCSection::BundleLockedAlignToEnd)
+ getOrCreateDataFragment()->setAlignToBundleEnd(false);
+ } else
+ Sec.setBundleLockState(MCSection::NotBundleLocked);
}
void MCELFStreamer::Flush() {
for (std::vector<LocalCommon>::const_iterator i = LocalCommons.begin(),
e = LocalCommons.end();
i != e; ++i) {
- MCSymbolData *SD = i->SD;
+ const MCSymbol &Symbol = *i->Symbol;
uint64_t Size = i->Size;
unsigned ByteAlignment = i->ByteAlignment;
- const MCSymbol &Symbol = SD->getSymbol();
- const MCSection &Section = Symbol.getSection();
+ MCSection &Section = Symbol.getSection();
- MCSectionData &SectData = getAssembler().getOrCreateSectionData(Section);
- new MCAlignFragment(ByteAlignment, 0, 1, ByteAlignment, &SectData);
+ getAssembler().registerSection(Section);
+ new MCAlignFragment(ByteAlignment, 0, 1, ByteAlignment, &Section);
- MCFragment *F = new MCFillFragment(0, 0, Size, &SectData);
- SD->setFragment(F);
+ MCFragment *F = new MCFillFragment(0, 0, Size, &Section);
+ Symbol.getData().setFragment(F);
// Update the maximum alignment of the section if necessary.
- if (ByteAlignment > SectData.getAlignment())
- SectData.setAlignment(ByteAlignment);
+ if (ByteAlignment > Section.getAlignment())
+ Section.setAlignment(ByteAlignment);
}
LocalCommons.clear();
}
void MCELFStreamer::FinishImpl() {
+ // Ensure the last section gets aligned if necessary.
+ MCSection *CurSection = getCurrentSectionOnly();
+ setSectionAlignmentForBundling(getAssembler(), CurSection);
+
EmitFrames(nullptr);
Flush();
}
MCStreamer *llvm::createELFStreamer(MCContext &Context, MCAsmBackend &MAB,
- raw_ostream &OS, MCCodeEmitter *CE,
+ raw_pwrite_stream &OS, MCCodeEmitter *CE,
bool RelaxAll) {
MCELFStreamer *S = new MCELFStreamer(Context, MAB, OS, CE);
if (RelaxAll)
llvm_unreachable("ELF doesn't support this directive");
}
-void MCELFStreamer::EmitZerofill(const MCSection *Section, MCSymbol *Symbol,
+void MCELFStreamer::EmitZerofill(MCSection *Section, MCSymbol *Symbol,
uint64_t Size, unsigned ByteAlignment) {
llvm_unreachable("ELF doesn't support this directive");
}
-void MCELFStreamer::EmitTBSSSymbol(const MCSection *Section, MCSymbol *Symbol,
+void MCELFStreamer::EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
uint64_t Size, unsigned ByteAlignment) {
llvm_unreachable("ELF doesn't support this directive");
}