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diff --git a/contrib/llvm-project/llvm/lib/MC/MCELFStreamer.cpp b/contrib/llvm-project/llvm/lib/MC/MCELFStreamer.cpp
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+++ b/contrib/llvm-project/llvm/lib/MC/MCELFStreamer.cpp
@@ -0,0 +1,708 @@
+//===- lib/MC/MCELFStreamer.cpp - ELF Object Output -----------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file assembles .s files and emits ELF .o object files.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCELFStreamer.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/BinaryFormat/ELF.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/MCExpr.h"
+#include "llvm/MC/MCFixup.h"
+#include "llvm/MC/MCFragment.h"
+#include "llvm/MC/MCObjectFileInfo.h"
+#include "llvm/MC/MCObjectWriter.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCSectionELF.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCSymbolELF.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Support/raw_ostream.h"
+#include <cassert>
+#include <cstdint>
+
+using namespace llvm;
+
+MCELFStreamer::MCELFStreamer(MCContext &Context,
+ std::unique_ptr<MCAsmBackend> TAB,
+ std::unique_ptr<MCObjectWriter> OW,
+ std::unique_ptr<MCCodeEmitter> Emitter)
+ : MCObjectStreamer(Context, std::move(TAB), std::move(OW),
+ std::move(Emitter)) {}
+
+bool MCELFStreamer::isBundleLocked() const {
+ return getCurrentSectionOnly()->isBundleLocked();
+}
+
+void MCELFStreamer::mergeFragment(MCDataFragment *DF,
+ MCDataFragment *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);
+ EF->setBundlePadding(static_cast<uint8_t>(RequiredBundlePadding));
+ Assembler.writeFragmentPadding(VecOS, *EF, FSize);
+
+ 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]);
+ }
+ if (DF->getSubtargetInfo() == nullptr && EF->getSubtargetInfo())
+ DF->setHasInstructions(*EF->getSubtargetInfo());
+ DF->getContents().append(EF->getContents().begin(), EF->getContents().end());
+}
+
+void MCELFStreamer::InitSections(bool NoExecStack) {
+ MCContext &Ctx = getContext();
+ SwitchSection(Ctx.getObjectFileInfo()->getTextSection());
+ EmitCodeAlignment(4);
+
+ if (NoExecStack)
+ SwitchSection(Ctx.getAsmInfo()->getNonexecutableStackSection(Ctx));
+}
+
+void MCELFStreamer::EmitLabel(MCSymbol *S, SMLoc Loc) {
+ auto *Symbol = cast<MCSymbolELF>(S);
+ MCObjectStreamer::EmitLabel(Symbol, Loc);
+
+ const MCSectionELF &Section =
+ static_cast<const MCSectionELF &>(*getCurrentSectionOnly());
+ if (Section.getFlags() & ELF::SHF_TLS)
+ Symbol->setType(ELF::STT_TLS);
+}
+
+void MCELFStreamer::EmitLabel(MCSymbol *S, SMLoc Loc, MCFragment *F) {
+ auto *Symbol = cast<MCSymbolELF>(S);
+ MCObjectStreamer::EmitLabel(Symbol, Loc, F);
+
+ const MCSectionELF &Section =
+ static_cast<const MCSectionELF &>(*getCurrentSectionOnly());
+ if (Section.getFlags() & ELF::SHF_TLS)
+ Symbol->setType(ELF::STT_TLS);
+}
+
+void MCELFStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
+ // Let the target do whatever target specific stuff it needs to do.
+ getAssembler().getBackend().handleAssemblerFlag(Flag);
+ // Do any generic stuff we need to do.
+ 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!");
+}
+
+// If bundle alignment 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) {
+ 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.registerSymbol(*Grp);
+
+ changeSectionImpl(Section, Subsection);
+ Asm.registerSymbol(*Section->getBeginSymbol());
+}
+
+void MCELFStreamer::EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {
+ getAssembler().registerSymbol(*Symbol);
+ const MCExpr *Value = MCSymbolRefExpr::create(
+ Symbol, MCSymbolRefExpr::VK_WEAKREF, getContext());
+ Alias->setVariableValue(Value);
+}
+
+// When GNU as encounters more than one .type declaration for an object it seems
+// to use a mechanism similar to the one below to decide which type is actually
+// used in the object file. The greater of T1 and T2 is selected based on the
+// following ordering:
+// STT_NOTYPE < STT_OBJECT < STT_FUNC < STT_GNU_IFUNC < STT_TLS < anything else
+// If neither T1 < T2 nor T2 < T1 according to this ordering, use T2 (the user
+// provided type).
+static unsigned CombineSymbolTypes(unsigned T1, unsigned T2) {
+ 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 == Type)
+ return T1;
+ }
+
+ return T2;
+}
+
+bool MCELFStreamer::EmitSymbolAttribute(MCSymbol *S, MCSymbolAttr Attribute) {
+ auto *Symbol = cast<MCSymbolELF>(S);
+
+ // Adding a symbol attribute always introduces the symbol, note that an
+ // important side effect of calling registerSymbol here is to register
+ // the symbol with the assembler.
+ getAssembler().registerSymbol(*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_Cold:
+ case MCSA_LazyReference:
+ case MCSA_Reference:
+ case MCSA_SymbolResolver:
+ case MCSA_PrivateExtern:
+ case MCSA_WeakDefinition:
+ case MCSA_WeakDefAutoPrivate:
+ case MCSA_Invalid:
+ case MCSA_IndirectSymbol:
+ return false;
+
+ case MCSA_NoDeadStrip:
+ // Ignore for now.
+ break;
+
+ case MCSA_ELF_TypeGnuUniqueObject:
+ Symbol->setType(CombineSymbolTypes(Symbol->getType(), ELF::STT_OBJECT));
+ Symbol->setBinding(ELF::STB_GNU_UNIQUE);
+ Symbol->setExternal(true);
+ break;
+
+ case MCSA_Global:
+ Symbol->setBinding(ELF::STB_GLOBAL);
+ Symbol->setExternal(true);
+ break;
+
+ case MCSA_WeakReference:
+ case MCSA_Weak:
+ Symbol->setBinding(ELF::STB_WEAK);
+ Symbol->setExternal(true);
+ break;
+
+ case MCSA_Local:
+ Symbol->setBinding(ELF::STB_LOCAL);
+ Symbol->setExternal(false);
+ break;
+
+ case MCSA_ELF_TypeFunction:
+ Symbol->setType(CombineSymbolTypes(Symbol->getType(), ELF::STT_FUNC));
+ break;
+
+ case MCSA_ELF_TypeIndFunction:
+ Symbol->setType(CombineSymbolTypes(Symbol->getType(), ELF::STT_GNU_IFUNC));
+ break;
+
+ case MCSA_ELF_TypeObject:
+ Symbol->setType(CombineSymbolTypes(Symbol->getType(), ELF::STT_OBJECT));
+ break;
+
+ case MCSA_ELF_TypeTLS:
+ Symbol->setType(CombineSymbolTypes(Symbol->getType(), ELF::STT_TLS));
+ break;
+
+ case MCSA_ELF_TypeCommon:
+ // TODO: Emit these as a common symbol.
+ Symbol->setType(CombineSymbolTypes(Symbol->getType(), ELF::STT_OBJECT));
+ break;
+
+ case MCSA_ELF_TypeNoType:
+ Symbol->setType(CombineSymbolTypes(Symbol->getType(), ELF::STT_NOTYPE));
+ break;
+
+ case MCSA_Protected:
+ Symbol->setVisibility(ELF::STV_PROTECTED);
+ break;
+
+ case MCSA_Hidden:
+ Symbol->setVisibility(ELF::STV_HIDDEN);
+ break;
+
+ case MCSA_Internal:
+ Symbol->setVisibility(ELF::STV_INTERNAL);
+ break;
+
+ case MCSA_AltEntry:
+ llvm_unreachable("ELF doesn't support the .alt_entry attribute");
+ }
+
+ return true;
+}
+
+void MCELFStreamer::EmitCommonSymbol(MCSymbol *S, uint64_t Size,
+ unsigned ByteAlignment) {
+ auto *Symbol = cast<MCSymbolELF>(S);
+ getAssembler().registerSymbol(*Symbol);
+
+ if (!Symbol->isBindingSet()) {
+ Symbol->setBinding(ELF::STB_GLOBAL);
+ Symbol->setExternal(true);
+ }
+
+ Symbol->setType(ELF::STT_OBJECT);
+
+ if (Symbol->getBinding() == ELF::STB_LOCAL) {
+ MCSection &Section = *getAssembler().getContext().getELFSection(
+ ".bss", ELF::SHT_NOBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
+ MCSectionSubPair P = getCurrentSection();
+ SwitchSection(&Section);
+
+ EmitValueToAlignment(ByteAlignment, 0, 1, 0);
+ EmitLabel(Symbol);
+ EmitZeros(Size);
+
+ // Update the maximum alignment of the section if necessary.
+ if (ByteAlignment > Section.getAlignment())
+ Section.setAlignment(ByteAlignment);
+
+ SwitchSection(P.first, P.second);
+ } else {
+ if(Symbol->declareCommon(Size, ByteAlignment))
+ report_fatal_error("Symbol: " + Symbol->getName() +
+ " redeclared as different type");
+ }
+
+ cast<MCSymbolELF>(Symbol)
+ ->setSize(MCConstantExpr::create(Size, getContext()));
+}
+
+void MCELFStreamer::emitELFSize(MCSymbol *Symbol, const MCExpr *Value) {
+ cast<MCSymbolELF>(Symbol)->setSize(Value);
+}
+
+void MCELFStreamer::emitELFSymverDirective(StringRef AliasName,
+ const MCSymbol *Aliasee) {
+ getAssembler().Symvers.push_back({AliasName, Aliasee});
+}
+
+void MCELFStreamer::EmitLocalCommonSymbol(MCSymbol *S, uint64_t Size,
+ unsigned ByteAlignment) {
+ auto *Symbol = cast<MCSymbolELF>(S);
+ // FIXME: Should this be caught and done earlier?
+ getAssembler().registerSymbol(*Symbol);
+ Symbol->setBinding(ELF::STB_LOCAL);
+ Symbol->setExternal(false);
+ EmitCommonSymbol(Symbol, Size, ByteAlignment);
+}
+
+void MCELFStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size,
+ SMLoc Loc) {
+ if (isBundleLocked())
+ report_fatal_error("Emitting values inside a locked bundle is forbidden");
+ fixSymbolsInTLSFixups(Value);
+ MCObjectStreamer::EmitValueImpl(Value, Size, Loc);
+}
+
+void MCELFStreamer::EmitValueToAlignment(unsigned ByteAlignment,
+ int64_t Value,
+ unsigned ValueSize,
+ unsigned MaxBytesToEmit) {
+ if (isBundleLocked())
+ report_fatal_error("Emitting values inside a locked bundle is forbidden");
+ MCObjectStreamer::EmitValueToAlignment(ByteAlignment, Value,
+ ValueSize, MaxBytesToEmit);
+}
+
+void MCELFStreamer::emitCGProfileEntry(const MCSymbolRefExpr *From,
+ const MCSymbolRefExpr *To,
+ uint64_t Count) {
+ getAssembler().CGProfile.push_back({From, To, Count});
+}
+
+void MCELFStreamer::EmitIdent(StringRef IdentString) {
+ MCSection *Comment = getAssembler().getContext().getELFSection(
+ ".comment", ELF::SHT_PROGBITS, ELF::SHF_MERGE | ELF::SHF_STRINGS, 1, "");
+ PushSection();
+ SwitchSection(Comment);
+ if (!SeenIdent) {
+ EmitIntValue(0, 1);
+ SeenIdent = true;
+ }
+ EmitBytes(IdentString);
+ EmitIntValue(0, 1);
+ PopSection();
+}
+
+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_TLSCALL:
+ case MCSymbolRefExpr::VK_TLSDESC:
+ case MCSymbolRefExpr::VK_TLSGD:
+ case MCSymbolRefExpr::VK_TLSLD:
+ case MCSymbolRefExpr::VK_TLSLDM:
+ case MCSymbolRefExpr::VK_TPOFF:
+ case MCSymbolRefExpr::VK_TPREL:
+ case MCSymbolRefExpr::VK_DTPOFF:
+ case MCSymbolRefExpr::VK_DTPREL:
+ case MCSymbolRefExpr::VK_PPC_DTPMOD:
+ case MCSymbolRefExpr::VK_PPC_TPREL_LO:
+ case MCSymbolRefExpr::VK_PPC_TPREL_HI:
+ case MCSymbolRefExpr::VK_PPC_TPREL_HA:
+ case MCSymbolRefExpr::VK_PPC_TPREL_HIGH:
+ case MCSymbolRefExpr::VK_PPC_TPREL_HIGHA:
+ case MCSymbolRefExpr::VK_PPC_TPREL_HIGHER:
+ case MCSymbolRefExpr::VK_PPC_TPREL_HIGHERA:
+ case MCSymbolRefExpr::VK_PPC_TPREL_HIGHEST:
+ case MCSymbolRefExpr::VK_PPC_TPREL_HIGHESTA:
+ case MCSymbolRefExpr::VK_PPC_DTPREL_LO:
+ case MCSymbolRefExpr::VK_PPC_DTPREL_HI:
+ case MCSymbolRefExpr::VK_PPC_DTPREL_HA:
+ case MCSymbolRefExpr::VK_PPC_DTPREL_HIGH:
+ case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHA:
+ case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHER:
+ case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHERA:
+ case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHEST:
+ case MCSymbolRefExpr::VK_PPC_DTPREL_HIGHESTA:
+ case MCSymbolRefExpr::VK_PPC_GOT_TPREL:
+ case MCSymbolRefExpr::VK_PPC_GOT_TPREL_LO:
+ case MCSymbolRefExpr::VK_PPC_GOT_TPREL_HI:
+ case MCSymbolRefExpr::VK_PPC_GOT_TPREL_HA:
+ case MCSymbolRefExpr::VK_PPC_GOT_DTPREL:
+ case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_LO:
+ case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_HI:
+ case MCSymbolRefExpr::VK_PPC_GOT_DTPREL_HA:
+ case MCSymbolRefExpr::VK_PPC_TLS:
+ case MCSymbolRefExpr::VK_PPC_GOT_TLSGD:
+ case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_LO:
+ case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_HI:
+ case MCSymbolRefExpr::VK_PPC_GOT_TLSGD_HA:
+ case MCSymbolRefExpr::VK_PPC_TLSGD:
+ case MCSymbolRefExpr::VK_PPC_GOT_TLSLD:
+ case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO:
+ case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_HI:
+ case MCSymbolRefExpr::VK_PPC_GOT_TLSLD_HA:
+ case MCSymbolRefExpr::VK_PPC_TLSLD:
+ break;
+ }
+ getAssembler().registerSymbol(symRef.getSymbol());
+ cast<MCSymbolELF>(symRef.getSymbol()).setType(ELF::STT_TLS);
+ break;
+ }
+
+ case MCExpr::Unary:
+ fixSymbolsInTLSFixups(cast<MCUnaryExpr>(expr)->getSubExpr());
+ break;
+ }
+}
+
+void MCELFStreamer::finalizeCGProfileEntry(const MCSymbolRefExpr *&SRE) {
+ const MCSymbol *S = &SRE->getSymbol();
+ if (S->isTemporary()) {
+ if (!S->isInSection()) {
+ getContext().reportError(
+ SRE->getLoc(), Twine("Reference to undefined temporary symbol ") +
+ "`" + S->getName() + "`");
+ return;
+ }
+ S = S->getSection().getBeginSymbol();
+ S->setUsedInReloc();
+ SRE =
+ MCSymbolRefExpr::create(S, SRE->getKind(), getContext(), SRE->getLoc());
+ return;
+ }
+ // Not a temporary, referece it as a weak undefined.
+ bool Created;
+ getAssembler().registerSymbol(*S, &Created);
+ if (Created) {
+ cast<MCSymbolELF>(S)->setBinding(ELF::STB_WEAK);
+ cast<MCSymbolELF>(S)->setExternal(true);
+ }
+}
+
+void MCELFStreamer::finalizeCGProfile() {
+ for (MCAssembler::CGProfileEntry &E : getAssembler().CGProfile) {
+ finalizeCGProfileEntry(E.From);
+ finalizeCGProfileEntry(E.To);
+ }
+}
+
+void MCELFStreamer::EmitInstToFragment(const MCInst &Inst,
+ const MCSubtargetInfo &STI) {
+ this->MCObjectStreamer::EmitInstToFragment(Inst, STI);
+ MCRelaxableFragment &F = *cast<MCRelaxableFragment>(getCurrentFragment());
+
+ for (unsigned i = 0, e = F.getFixups().size(); i != e; ++i)
+ fixSymbolsInTLSFixups(F.getFixups()[i].getValue());
+}
+
+// A fragment can only have one Subtarget, and when bundling is enabled we
+// sometimes need to use the same fragment. We give an error if there
+// are conflicting Subtargets.
+static void CheckBundleSubtargets(const MCSubtargetInfo *OldSTI,
+ const MCSubtargetInfo *NewSTI) {
+ if (OldSTI && NewSTI && OldSTI != NewSTI)
+ report_fatal_error("A Bundle can only have one Subtarget.");
+}
+
+void MCELFStreamer::EmitInstToData(const MCInst &Inst,
+ const MCSubtargetInfo &STI) {
+ MCAssembler &Assembler = getAssembler();
+ SmallVector<MCFixup, 4> Fixups;
+ SmallString<256> Code;
+ raw_svector_ostream VecOS(Code);
+ Assembler.getEmitter().encodeInstruction(Inst, VecOS, Fixups, STI);
+
+ 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, or the Subtarget has changed).
+ //
+ // 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()) {
+ 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();
+ CheckBundleSubtargets(DF->getSubtargetInfo(), &STI);
+ }
+ 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());
+ CheckBundleSubtargets(DF->getSubtargetInfo(), &STI);
+ }
+ 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.
+ MCCompactEncodedInstFragment *CEIF = new MCCompactEncodedInstFragment();
+ insert(CEIF);
+ CEIF->getContents().append(Code.begin(), Code.end());
+ CEIF->setHasInstructions(STI);
+ return;
+ } else {
+ DF = new MCDataFragment();
+ insert(DF);
+ }
+ 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
+ // is the one marked align_to_end.
+ DF->setAlignToBundleEnd(true);
+ }
+
+ // We're now emitting an instruction in a bundle group, so this flag has
+ // to be turned off.
+ Sec.setBundleGroupBeforeFirstInst(false);
+ } else {
+ DF = getOrCreateDataFragment(&STI);
+ }
+
+ // 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(STI);
+ DF->getContents().append(Code.begin(), Code.end());
+
+ if (Assembler.isBundlingEnabled() && Assembler.getRelaxAll()) {
+ if (!isBundleLocked()) {
+ mergeFragment(getOrCreateDataFragment(&STI), DF);
+ delete DF;
+ }
+ }
+}
+
+void MCELFStreamer::EmitBundleAlignMode(unsigned AlignPow2) {
+ assert(AlignPow2 <= 30 && "Invalid bundle alignment");
+ MCAssembler &Assembler = getAssembler();
+ if (AlignPow2 > 0 && (Assembler.getBundleAlignSize() == 0 ||
+ Assembler.getBundleAlignSize() == 1U << AlignPow2))
+ Assembler.setBundleAlignSize(1U << AlignPow2);
+ else
+ report_fatal_error(".bundle_align_mode cannot be changed once set");
+}
+
+void MCELFStreamer::EmitBundleLock(bool AlignToEnd) {
+ MCSection &Sec = *getCurrentSectionOnly();
+
+ // Sanity checks
+ //
+ if (!getAssembler().isBundlingEnabled())
+ report_fatal_error(".bundle_lock forbidden when bundling is disabled");
+
+ if (!isBundleLocked())
+ Sec.setBundleGroupBeforeFirstInst(true);
+
+ 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() {
+ MCSection &Sec = *getCurrentSectionOnly();
+
+ // Sanity checks
+ if (!getAssembler().isBundlingEnabled())
+ report_fatal_error(".bundle_unlock forbidden when bundling is disabled");
+ else if (!isBundleLocked())
+ report_fatal_error(".bundle_unlock without matching lock");
+ else if (Sec.isBundleGroupBeforeFirstInst())
+ report_fatal_error("Empty bundle-locked group is forbidden");
+
+ // When the -mc-relax-all flag is used, we emit instructions to fragments
+ // stored on a stack. When the bundle unlock is emitted, 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->getSubtargetInfo()), DF);
+ BundleGroups.pop_back();
+ delete DF;
+ }
+
+ if (Sec.getBundleLockState() != MCSection::BundleLockedAlignToEnd)
+ getOrCreateDataFragment()->setAlignToBundleEnd(false);
+ } else
+ Sec.setBundleLockState(MCSection::NotBundleLocked);
+}
+
+void MCELFStreamer::FinishImpl() {
+ // Ensure the last section gets aligned if necessary.
+ MCSection *CurSection = getCurrentSectionOnly();
+ setSectionAlignmentForBundling(getAssembler(), CurSection);
+
+ finalizeCGProfile();
+ EmitFrames(nullptr);
+
+ this->MCObjectStreamer::FinishImpl();
+}
+
+void MCELFStreamer::EmitThumbFunc(MCSymbol *Func) {
+ llvm_unreachable("Generic ELF doesn't support this directive");
+}
+
+void MCELFStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
+ llvm_unreachable("ELF doesn't support this directive");
+}
+
+void MCELFStreamer::EmitZerofill(MCSection *Section, MCSymbol *Symbol,
+ uint64_t Size, unsigned ByteAlignment,
+ SMLoc Loc) {
+ llvm_unreachable("ELF doesn't support this directive");
+}
+
+void MCELFStreamer::EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
+ uint64_t Size, unsigned ByteAlignment) {
+ llvm_unreachable("ELF doesn't support this directive");
+}
+
+MCStreamer *llvm::createELFStreamer(MCContext &Context,
+ std::unique_ptr<MCAsmBackend> &&MAB,
+ std::unique_ptr<MCObjectWriter> &&OW,
+ std::unique_ptr<MCCodeEmitter> &&CE,
+ bool RelaxAll) {
+ MCELFStreamer *S =
+ new MCELFStreamer(Context, std::move(MAB), std::move(OW), std::move(CE));
+ if (RelaxAll)
+ S->getAssembler().setRelaxAll(true);
+ return S;
+}