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-rw-r--r--contrib/llvm/lib/MC/MCELFStreamer.cpp552
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diff --git a/contrib/llvm/lib/MC/MCELFStreamer.cpp b/contrib/llvm/lib/MC/MCELFStreamer.cpp
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+++ b/contrib/llvm/lib/MC/MCELFStreamer.cpp
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+//===- lib/MC/MCELFStreamer.cpp - ELF Object Output -----------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file assembles .s files and emits ELF .o object files.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCELFStreamer.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCCodeEmitter.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCELF.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/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/raw_ostream.h"
+
+using namespace llvm;
+
+
+inline void MCELFStreamer::SetSection(StringRef Section, unsigned Type,
+ unsigned Flags, SectionKind Kind) {
+ SwitchSection(getContext().getELFSection(Section, Type, Flags, Kind));
+}
+
+inline void MCELFStreamer::SetSectionData() {
+ SetSection(".data",
+ ELF::SHT_PROGBITS,
+ ELF::SHF_WRITE | ELF::SHF_ALLOC,
+ SectionKind::getDataRel());
+ EmitCodeAlignment(4, 0);
+}
+
+inline void MCELFStreamer::SetSectionText() {
+ SetSection(".text",
+ ELF::SHT_PROGBITS,
+ ELF::SHF_EXECINSTR | ELF::SHF_ALLOC,
+ SectionKind::getText());
+ EmitCodeAlignment(4, 0);
+}
+
+inline void MCELFStreamer::SetSectionBss() {
+ SetSection(".bss",
+ ELF::SHT_NOBITS,
+ ELF::SHF_WRITE | ELF::SHF_ALLOC,
+ SectionKind::getBSS());
+ EmitCodeAlignment(4, 0);
+}
+
+MCELFStreamer::~MCELFStreamer() {
+}
+
+void MCELFStreamer::InitToTextSection() {
+ SetSectionText();
+}
+
+void MCELFStreamer::InitSections() {
+ // 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.
+ SetSectionText();
+ SetSectionData();
+ SetSectionBss();
+ SetSectionText();
+}
+
+void MCELFStreamer::EmitLabel(MCSymbol *Symbol) {
+ assert(Symbol->isUndefined() && "Cannot define a symbol twice!");
+
+ MCObjectStreamer::EmitLabel(Symbol);
+
+ 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);
+}
+
+void MCELFStreamer::EmitDebugLabel(MCSymbol *Symbol) {
+ EmitLabel(Symbol);
+}
+
+void MCELFStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
+ switch (Flag) {
+ case MCAF_SyntaxUnified: return; // no-op here.
+ case MCAF_Code16: return; // Change parsing mode; no-op here.
+ case MCAF_Code32: return; // Change parsing mode; no-op here.
+ case MCAF_Code64: return; // Change parsing mode; no-op here.
+ case MCAF_SubsectionsViaSymbols:
+ getAssembler().setSubsectionsViaSymbols(true);
+ return;
+ }
+
+ llvm_unreachable("invalid assembler flag!");
+}
+
+void MCELFStreamer::ChangeSection(const MCSection *Section) {
+ MCSectionData *CurSection = getCurrentSectionData();
+ if (CurSection && CurSection->isBundleLocked())
+ report_fatal_error("Unterminated .bundle_lock when changing a section");
+ const MCSymbol *Grp = static_cast<const MCSectionELF *>(Section)->getGroup();
+ if (Grp)
+ getAssembler().getOrCreateSymbolData(*Grp);
+ this->MCObjectStreamer::ChangeSection(Section);
+}
+
+void MCELFStreamer::EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {
+ getAssembler().getOrCreateSymbolData(*Symbol);
+ MCSymbolData &AliasSD = getAssembler().getOrCreateSymbolData(*Alias);
+ AliasSD.setFlags(AliasSD.getFlags() | ELF_Other_Weakref);
+ const MCExpr *Value = MCSymbolRefExpr::Create(Symbol, getContext());
+ Alias->setVariableValue(Value);
+}
+
+void MCELFStreamer::EmitSymbolAttribute(MCSymbol *Symbol,
+ MCSymbolAttr Attribute) {
+ // Indirect symbols are handled differently, to match how 'as' handles
+ // them. This makes writing matching .o files easier.
+ if (Attribute == MCSA_IndirectSymbol) {
+ // Note that we intentionally cannot use the symbol data here; this is
+ // important for matching the string table that 'as' generates.
+ IndirectSymbolData ISD;
+ ISD.Symbol = Symbol;
+ ISD.SectionData = getCurrentSectionData();
+ getAssembler().getIndirectSymbols().push_back(ISD);
+ return;
+ }
+
+ // Adding a symbol attribute always introduces the symbol, note that an
+ // important side effect of calling getOrCreateSymbolData here is to register
+ // the symbol with the assembler.
+ MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
+
+ // 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
+ // remove flags, but 'as' allows this (in particular, see .desc).
+ //
+ // In the future it might be worth trying to make these operations more well
+ // defined.
+ switch (Attribute) {
+ case MCSA_LazyReference:
+ case MCSA_Reference:
+ case MCSA_SymbolResolver:
+ case MCSA_PrivateExtern:
+ case MCSA_WeakDefinition:
+ case MCSA_WeakDefAutoPrivate:
+ case MCSA_Invalid:
+ case MCSA_IndirectSymbol:
+ llvm_unreachable("Invalid symbol attribute for ELF!");
+
+ case MCSA_NoDeadStrip:
+ case MCSA_ELF_TypeGnuUniqueObject:
+ // Ignore for now.
+ break;
+
+ case MCSA_Global:
+ MCELF::SetBinding(SD, ELF::STB_GLOBAL);
+ SD.setExternal(true);
+ BindingExplicitlySet.insert(Symbol);
+ break;
+
+ case MCSA_WeakReference:
+ case MCSA_Weak:
+ MCELF::SetBinding(SD, ELF::STB_WEAK);
+ SD.setExternal(true);
+ BindingExplicitlySet.insert(Symbol);
+ break;
+
+ case MCSA_Local:
+ MCELF::SetBinding(SD, ELF::STB_LOCAL);
+ SD.setExternal(false);
+ BindingExplicitlySet.insert(Symbol);
+ break;
+
+ case MCSA_ELF_TypeFunction:
+ MCELF::SetType(SD, ELF::STT_FUNC);
+ break;
+
+ case MCSA_ELF_TypeIndFunction:
+ MCELF::SetType(SD, ELF::STT_GNU_IFUNC);
+ break;
+
+ case MCSA_ELF_TypeObject:
+ MCELF::SetType(SD, ELF::STT_OBJECT);
+ break;
+
+ case MCSA_ELF_TypeTLS:
+ MCELF::SetType(SD, ELF::STT_TLS);
+ break;
+
+ case MCSA_ELF_TypeCommon:
+ MCELF::SetType(SD, ELF::STT_COMMON);
+ break;
+
+ case MCSA_ELF_TypeNoType:
+ MCELF::SetType(SD, ELF::STT_NOTYPE);
+ break;
+
+ case MCSA_Protected:
+ MCELF::SetVisibility(SD, ELF::STV_PROTECTED);
+ break;
+
+ case MCSA_Hidden:
+ MCELF::SetVisibility(SD, ELF::STV_HIDDEN);
+ break;
+
+ case MCSA_Internal:
+ MCELF::SetVisibility(SD, ELF::STV_INTERNAL);
+ break;
+ }
+}
+
+void MCELFStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
+ unsigned ByteAlignment) {
+ MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
+
+ if (!BindingExplicitlySet.count(Symbol)) {
+ MCELF::SetBinding(SD, ELF::STB_GLOBAL);
+ SD.setExternal(true);
+ }
+
+ MCELF::SetType(SD, 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());
+ Symbol->setSection(*Section);
+
+ struct LocalCommon L = {&SD, Size, ByteAlignment};
+ LocalCommons.push_back(L);
+ } else {
+ SD.setCommon(Size, ByteAlignment);
+ }
+
+ SD.setSize(MCConstantExpr::Create(Size, getContext()));
+}
+
+void MCELFStreamer::EmitELFSize(MCSymbol *Symbol, const MCExpr *Value) {
+ MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
+ SD.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);
+ SD.setExternal(false);
+ BindingExplicitlySet.insert(Symbol);
+ EmitCommonSymbol(Symbol, Size, ByteAlignment);
+}
+
+void MCELFStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size,
+ unsigned AddrSpace) {
+ if (getCurrentSectionData()->isBundleLocked())
+ report_fatal_error("Emitting values inside a locked bundle is forbidden");
+ fixSymbolsInTLSFixups(Value);
+ MCObjectStreamer::EmitValueImpl(Value, Size, AddrSpace);
+}
+
+void MCELFStreamer::EmitValueToAlignment(unsigned ByteAlignment,
+ int64_t Value,
+ unsigned ValueSize,
+ unsigned MaxBytesToEmit) {
+ if (getCurrentSectionData()->isBundleLocked())
+ report_fatal_error("Emitting values inside a locked bundle is forbidden");
+ MCObjectStreamer::EmitValueToAlignment(ByteAlignment, Value,
+ ValueSize, MaxBytesToEmit);
+}
+
+
+// Add a symbol for the file name of this module. This is the second
+// entry in the module's symbol table (the first being the null symbol).
+void MCELFStreamer::EmitFileDirective(StringRef Filename) {
+ MCSymbol *Symbol = getAssembler().getContext().GetOrCreateSymbol(Filename);
+ Symbol->setSection(*getCurrentSection());
+ Symbol->setAbsolute();
+
+ MCSymbolData &SD = getAssembler().getOrCreateSymbolData(*Symbol);
+
+ SD.setFlags(ELF_STT_File | ELF_STB_Local | ELF_STV_Default);
+}
+
+void MCELFStreamer::fixSymbolsInTLSFixups(const MCExpr *expr) {
+ switch (expr->getKind()) {
+ case MCExpr::Target:
+ cast<MCTargetExpr>(expr)->fixELFSymbolsInTLSFixups(getAssembler());
+ break;
+ case MCExpr::Constant:
+ break;
+
+ case MCExpr::Binary: {
+ const MCBinaryExpr *be = cast<MCBinaryExpr>(expr);
+ fixSymbolsInTLSFixups(be->getLHS());
+ fixSymbolsInTLSFixups(be->getRHS());
+ break;
+ }
+
+ case MCExpr::SymbolRef: {
+ const MCSymbolRefExpr &symRef = *cast<MCSymbolRefExpr>(expr);
+ switch (symRef.getKind()) {
+ default:
+ return;
+ case MCSymbolRefExpr::VK_GOTTPOFF:
+ case MCSymbolRefExpr::VK_INDNTPOFF:
+ case MCSymbolRefExpr::VK_NTPOFF:
+ case MCSymbolRefExpr::VK_GOTNTPOFF:
+ case MCSymbolRefExpr::VK_TLSGD:
+ case MCSymbolRefExpr::VK_TLSLD:
+ case MCSymbolRefExpr::VK_TLSLDM:
+ case MCSymbolRefExpr::VK_TPOFF:
+ case MCSymbolRefExpr::VK_DTPOFF:
+ case MCSymbolRefExpr::VK_ARM_TLSGD:
+ case MCSymbolRefExpr::VK_ARM_TPOFF:
+ case MCSymbolRefExpr::VK_ARM_GOTTPOFF:
+ case MCSymbolRefExpr::VK_Mips_TLSGD:
+ case MCSymbolRefExpr::VK_Mips_GOTTPREL:
+ case MCSymbolRefExpr::VK_Mips_TPREL_HI:
+ case MCSymbolRefExpr::VK_Mips_TPREL_LO:
+ case MCSymbolRefExpr::VK_PPC_TPREL16_HA:
+ case MCSymbolRefExpr::VK_PPC_TPREL16_LO:
+ case MCSymbolRefExpr::VK_PPC_DTPREL16_HA:
+ case MCSymbolRefExpr::VK_PPC_DTPREL16_LO:
+ case MCSymbolRefExpr::VK_PPC_GOT_TPREL16_HA:
+ case MCSymbolRefExpr::VK_PPC_GOT_TPREL16_LO:
+ case MCSymbolRefExpr::VK_PPC_TLS:
+ case MCSymbolRefExpr::VK_PPC_GOT_TLSGD16_HA:
+ case MCSymbolRefExpr::VK_PPC_GOT_TLSGD16_LO:
+ case MCSymbolRefExpr::VK_PPC_TLSGD:
+ case MCSymbolRefExpr::VK_PPC_GOT_TLSLD16_HA:
+ case MCSymbolRefExpr::VK_PPC_GOT_TLSLD16_LO:
+ case MCSymbolRefExpr::VK_PPC_TLSLD:
+ break;
+ }
+ MCSymbolData &SD = getAssembler().getOrCreateSymbolData(symRef.getSymbol());
+ MCELF::SetType(SD, ELF::STT_TLS);
+ break;
+ }
+
+ case MCExpr::Unary:
+ fixSymbolsInTLSFixups(cast<MCUnaryExpr>(expr)->getSubExpr());
+ break;
+ }
+}
+
+void MCELFStreamer::EmitInstToFragment(const MCInst &Inst) {
+ this->MCObjectStreamer::EmitInstToFragment(Inst);
+ MCRelaxableFragment &F = *cast<MCRelaxableFragment>(getCurrentFragment());
+
+ for (unsigned i = 0, e = F.getFixups().size(); i != e; ++i)
+ fixSymbolsInTLSFixups(F.getFixups()[i].getValue());
+}
+
+void MCELFStreamer::EmitInstToData(const MCInst &Inst) {
+ MCAssembler &Assembler = getAssembler();
+ SmallVector<MCFixup, 4> Fixups;
+ SmallString<256> Code;
+ raw_svector_ostream VecOS(Code);
+ Assembler.getEmitter().EncodeInstruction(Inst, VecOS, Fixups);
+ VecOS.flush();
+
+ for (unsigned i = 0, e = Fixups.size(); i != e; ++i)
+ fixSymbolsInTLSFixups(Fixups[i].getValue());
+
+ // There are several possibilities here:
+ //
+ // If bundling is disabled, append the encoded instruction to the current data
+ // fragment (or create a new such fragment if the current fragment is not a
+ // data fragment).
+ //
+ // If bundling is enabled:
+ // - If we're not in a bundle-locked group, emit the instruction into a
+ // fragment of its own. If there are no fixups registered for the
+ // instruction, emit a MCCompactEncodedInstFragment. Otherwise, emit a
+ // MCDataFragment.
+ // - If we're in a bundle-locked group, append the instruction to the current
+ // data fragment because we want all the instructions in a group to get into
+ // the same fragment. Be careful not to do that for the first instruction in
+ // the group, though.
+ MCDataFragment *DF;
+
+ if (Assembler.isBundlingEnabled()) {
+ MCSectionData *SD = getCurrentSectionData();
+ if (SD->isBundleLocked() && !SD->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) {
+ // Optimize memory usage by emitting the instruction to a
+ // MCCompactEncodedInstFragment when not in a bundle-locked group and
+ // there are no fixups registered.
+ MCCompactEncodedInstFragment *CEIF = new MCCompactEncodedInstFragment(SD);
+ CEIF->getContents().append(Code.begin(), Code.end());
+ return;
+ } else {
+ DF = new MCDataFragment(SD);
+ if (SD->getBundleLockState() == MCSectionData::BundleLockedAlignToEnd) {
+ // If this is a new fragment created for a bundle-locked group, and the
+ // group was marked as "align_to_end", set a flag in the fragment.
+ DF->setAlignToBundleEnd(true);
+ }
+ }
+
+ // We're now emitting an instruction in a bundle group, so this flag has
+ // to be turned off.
+ SD->setBundleGroupBeforeFirstInst(false);
+ } else {
+ DF = getOrCreateDataFragment();
+ }
+
+ // Add the fixups and data.
+ for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
+ Fixups[i].setOffset(Fixups[i].getOffset() + DF->getContents().size());
+ DF->getFixups().push_back(Fixups[i]);
+ }
+ DF->setHasInstructions(true);
+ DF->getContents().append(Code.begin(), Code.end());
+}
+
+void MCELFStreamer::EmitBundleAlignMode(unsigned AlignPow2) {
+ assert(AlignPow2 <= 30 && "Invalid bundle alignment");
+ MCAssembler &Assembler = getAssembler();
+ if (Assembler.getBundleAlignSize() == 0 && AlignPow2 > 0)
+ Assembler.setBundleAlignSize(1 << AlignPow2);
+ else
+ report_fatal_error(".bundle_align_mode should be only set once per file");
+}
+
+void MCELFStreamer::EmitBundleLock(bool AlignToEnd) {
+ MCSectionData *SD = getCurrentSectionData();
+
+ // Sanity checks
+ //
+ if (!getAssembler().isBundlingEnabled())
+ report_fatal_error(".bundle_lock forbidden when bundling is disabled");
+ else if (SD->isBundleLocked())
+ report_fatal_error("Nesting of .bundle_lock is forbidden");
+
+ SD->setBundleLockState(AlignToEnd ? MCSectionData::BundleLockedAlignToEnd :
+ MCSectionData::BundleLocked);
+ SD->setBundleGroupBeforeFirstInst(true);
+}
+
+void MCELFStreamer::EmitBundleUnlock() {
+ MCSectionData *SD = getCurrentSectionData();
+
+ // Sanity checks
+ if (!getAssembler().isBundlingEnabled())
+ report_fatal_error(".bundle_unlock forbidden when bundling is disabled");
+ else if (!SD->isBundleLocked())
+ report_fatal_error(".bundle_unlock without matching lock");
+ else if (SD->isBundleGroupBeforeFirstInst())
+ report_fatal_error("Empty bundle-locked group is forbidden");
+
+ SD->setBundleLockState(MCSectionData::NotBundleLocked);
+}
+
+void MCELFStreamer::FinishImpl() {
+ EmitFrames(true);
+
+ for (std::vector<LocalCommon>::const_iterator i = LocalCommons.begin(),
+ e = LocalCommons.end();
+ i != e; ++i) {
+ MCSymbolData *SD = i->SD;
+ uint64_t Size = i->Size;
+ unsigned ByteAlignment = i->ByteAlignment;
+ const MCSymbol &Symbol = SD->getSymbol();
+ const MCSection &Section = Symbol.getSection();
+
+ MCSectionData &SectData = getAssembler().getOrCreateSectionData(Section);
+ new MCAlignFragment(ByteAlignment, 0, 1, ByteAlignment, &SectData);
+
+ MCFragment *F = new MCFillFragment(0, 0, Size, &SectData);
+ SD->setFragment(F);
+
+ // Update the maximum alignment of the section if necessary.
+ if (ByteAlignment > SectData.getAlignment())
+ SectData.setAlignment(ByteAlignment);
+ }
+
+ this->MCObjectStreamer::FinishImpl();
+}
+void MCELFStreamer::EmitTCEntry(const MCSymbol &S) {
+ // Creates a R_PPC64_TOC relocation
+ MCObjectStreamer::EmitSymbolValue(&S, 8);
+}
+
+MCStreamer *llvm::createELFStreamer(MCContext &Context, MCAsmBackend &MAB,
+ raw_ostream &OS, MCCodeEmitter *CE,
+ bool RelaxAll, bool NoExecStack) {
+ MCELFStreamer *S = new MCELFStreamer(Context, MAB, OS, CE);
+ if (RelaxAll)
+ S->getAssembler().setRelaxAll(true);
+ if (NoExecStack)
+ S->getAssembler().setNoExecStack(true);
+ return S;
+}
+
+void MCELFStreamer::EmitThumbFunc(MCSymbol *Func) {
+ llvm_unreachable("Generic ELF doesn't support this directive");
+}
+
+MCSymbolData &MCELFStreamer::getOrCreateSymbolData(MCSymbol *Symbol) {
+ return getAssembler().getOrCreateSymbolData(*Symbol);
+}
+
+void MCELFStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
+ llvm_unreachable("ELF doesn't support this directive");
+}
+
+void MCELFStreamer::BeginCOFFSymbolDef(const MCSymbol *Symbol) {
+ llvm_unreachable("ELF doesn't support this directive");
+}
+
+void MCELFStreamer::EmitCOFFSymbolStorageClass(int StorageClass) {
+ llvm_unreachable("ELF doesn't support this directive");
+}
+
+void MCELFStreamer::EmitCOFFSymbolType(int Type) {
+ llvm_unreachable("ELF doesn't support this directive");
+}
+
+void MCELFStreamer::EndCOFFSymbolDef() {
+ llvm_unreachable("ELF doesn't support this directive");
+}
+
+void MCELFStreamer::EmitZerofill(const 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,
+ uint64_t Size, unsigned ByteAlignment) {
+ llvm_unreachable("ELF doesn't support this directive");
+}
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