1 files changed, 0 insertions, 1154 deletions

diff --git a/contrib/llvm/lib/MC/MCAssembler.cpp b/contrib/llvm/lib/MC/MCAssembler.cpp
deleted file mode 100644
index 22a8e73e4af3..000000000000
--- a/contrib/llvm/lib/MC/MCAssembler.cpp
+++ /dev/null
@@ -1,1154 +0,0 @@
-//===- lib/MC/MCAssembler.cpp - Assembler Backend Implementation ----------===//
-//
-// 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
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/MC/MCAssembler.h"
-#include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/SmallString.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/StringRef.h"
-#include "llvm/ADT/Twine.h"
-#include "llvm/MC/MCAsmBackend.h"
-#include "llvm/MC/MCAsmInfo.h"
-#include "llvm/MC/MCAsmLayout.h"
-#include "llvm/MC/MCCodeEmitter.h"
-#include "llvm/MC/MCCodeView.h"
-#include "llvm/MC/MCContext.h"
-#include "llvm/MC/MCDwarf.h"
-#include "llvm/MC/MCExpr.h"
-#include "llvm/MC/MCFixup.h"
-#include "llvm/MC/MCFixupKindInfo.h"
-#include "llvm/MC/MCFragment.h"
-#include "llvm/MC/MCInst.h"
-#include "llvm/MC/MCObjectWriter.h"
-#include "llvm/MC/MCSection.h"
-#include "llvm/MC/MCSectionELF.h"
-#include "llvm/MC/MCSymbol.h"
-#include "llvm/MC/MCValue.h"
-#include "llvm/Support/Casting.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/LEB128.h"
-#include "llvm/Support/MathExtras.h"
-#include "llvm/Support/raw_ostream.h"
-#include <cassert>
-#include <cstdint>
-#include <cstring>
-#include <tuple>
-#include <utility>
-
-using namespace llvm;
-
-#define DEBUG_TYPE "assembler"
-
-namespace {
-namespace stats {
-
-STATISTIC(EmittedFragments, "Number of emitted assembler fragments - total");
-STATISTIC(EmittedRelaxableFragments,
-          "Number of emitted assembler fragments - relaxable");
-STATISTIC(EmittedDataFragments,
-          "Number of emitted assembler fragments - data");
-STATISTIC(EmittedCompactEncodedInstFragments,
-          "Number of emitted assembler fragments - compact encoded inst");
-STATISTIC(EmittedAlignFragments,
-          "Number of emitted assembler fragments - align");
-STATISTIC(EmittedFillFragments,
-          "Number of emitted assembler fragments - fill");
-STATISTIC(EmittedOrgFragments,
-          "Number of emitted assembler fragments - org");
-STATISTIC(evaluateFixup, "Number of evaluated fixups");
-STATISTIC(FragmentLayouts, "Number of fragment layouts");
-STATISTIC(ObjectBytes, "Number of emitted object file bytes");
-STATISTIC(RelaxationSteps, "Number of assembler layout and relaxation steps");
-STATISTIC(RelaxedInstructions, "Number of relaxed instructions");
-STATISTIC(PaddingFragmentsRelaxations,
-          "Number of Padding Fragments relaxations");
-STATISTIC(PaddingFragmentsBytes,
-          "Total size of all padding from adding Fragments");
-
-} // end namespace stats
-} // end anonymous namespace
-
-// FIXME FIXME FIXME: There are number of places in this file where we convert
-// what is a 64-bit assembler value used for computation into a value in the
-// object file, which may truncate it. We should detect that truncation where
-// invalid and report errors back.
-
-/* *** */
-
-MCAssembler::MCAssembler(MCContext &Context,
-                         std::unique_ptr<MCAsmBackend> Backend,
-                         std::unique_ptr<MCCodeEmitter> Emitter,
-                         std::unique_ptr<MCObjectWriter> Writer)
-    : Context(Context), Backend(std::move(Backend)),
-      Emitter(std::move(Emitter)), Writer(std::move(Writer)),
-      BundleAlignSize(0), RelaxAll(false), SubsectionsViaSymbols(false),
-      IncrementalLinkerCompatible(false), ELFHeaderEFlags(0) {
-  VersionInfo.Major = 0; // Major version == 0 for "none specified"
-}
-
-MCAssembler::~MCAssembler() = default;
-
-void MCAssembler::reset() {
-  Sections.clear();
-  Symbols.clear();
-  IndirectSymbols.clear();
-  DataRegions.clear();
-  LinkerOptions.clear();
-  FileNames.clear();
-  ThumbFuncs.clear();
-  BundleAlignSize = 0;
-  RelaxAll = false;
-  SubsectionsViaSymbols = false;
-  IncrementalLinkerCompatible = false;
-  ELFHeaderEFlags = 0;
-  LOHContainer.reset();
-  VersionInfo.Major = 0;
-  VersionInfo.SDKVersion = VersionTuple();
-
-  // reset objects owned by us
-  if (getBackendPtr())
-    getBackendPtr()->reset();
-  if (getEmitterPtr())
-    getEmitterPtr()->reset();
-  if (getWriterPtr())
-    getWriterPtr()->reset();
-  getLOHContainer().reset();
-}
-
-bool MCAssembler::registerSection(MCSection &Section) {
-  if (Section.isRegistered())
-    return false;
-  Sections.push_back(&Section);
-  Section.setIsRegistered(true);
-  return true;
-}
-
-bool MCAssembler::isThumbFunc(const MCSymbol *Symbol) const {
-  if (ThumbFuncs.count(Symbol))
-    return true;
-
-  if (!Symbol->isVariable())
-    return false;
-
-  const MCExpr *Expr = Symbol->getVariableValue();
-
-  MCValue V;
-  if (!Expr->evaluateAsRelocatable(V, nullptr, nullptr))
-    return false;
-
-  if (V.getSymB() || V.getRefKind() != MCSymbolRefExpr::VK_None)
-    return false;
-
-  const MCSymbolRefExpr *Ref = V.getSymA();
-  if (!Ref)
-    return false;
-
-  if (Ref->getKind() != MCSymbolRefExpr::VK_None)
-    return false;
-
-  const MCSymbol &Sym = Ref->getSymbol();
-  if (!isThumbFunc(&Sym))
-    return false;
-
-  ThumbFuncs.insert(Symbol); // Cache it.
-  return true;
-}
-
-bool MCAssembler::isSymbolLinkerVisible(const MCSymbol &Symbol) const {
-  // Non-temporary labels should always be visible to the linker.
-  if (!Symbol.isTemporary())
-    return true;
-
-  // Absolute temporary labels are never visible.
-  if (!Symbol.isInSection())
-    return false;
-
-  if (Symbol.isUsedInReloc())
-    return true;
-
-  return false;
-}
-
-const MCSymbol *MCAssembler::getAtom(const MCSymbol &S) const {
-  // Linker visible symbols define atoms.
-  if (isSymbolLinkerVisible(S))
-    return &S;
-
-  // Absolute and undefined symbols have no defining atom.
-  if (!S.isInSection())
-    return nullptr;
-
-  // Non-linker visible symbols in sections which can't be atomized have no
-  // defining atom.
-  if (!getContext().getAsmInfo()->isSectionAtomizableBySymbols(
-          *S.getFragment()->getParent()))
-    return nullptr;
-
-  // Otherwise, return the atom for the containing fragment.
-  return S.getFragment()->getAtom();
-}
-
-bool MCAssembler::evaluateFixup(const MCAsmLayout &Layout,
-                                const MCFixup &Fixup, const MCFragment *DF,
-                                MCValue &Target, uint64_t &Value,
-                                bool &WasForced) const {
-  ++stats::evaluateFixup;
-
-  // FIXME: This code has some duplication with recordRelocation. We should
-  // probably merge the two into a single callback that tries to evaluate a
-  // fixup and records a relocation if one is needed.
-
-  // On error claim to have completely evaluated the fixup, to prevent any
-  // further processing from being done.
-  const MCExpr *Expr = Fixup.getValue();
-  MCContext &Ctx = getContext();
-  Value = 0;
-  WasForced = false;
-  if (!Expr->evaluateAsRelocatable(Target, &Layout, &Fixup)) {
-    Ctx.reportError(Fixup.getLoc(), "expected relocatable expression");
-    return true;
-  }
-  if (const MCSymbolRefExpr *RefB = Target.getSymB()) {
-    if (RefB->getKind() != MCSymbolRefExpr::VK_None) {
-      Ctx.reportError(Fixup.getLoc(),
-                      "unsupported subtraction of qualified symbol");
-      return true;
-    }
-  }
-
-  assert(getBackendPtr() && "Expected assembler backend");
-  bool IsPCRel = getBackendPtr()->getFixupKindInfo(Fixup.getKind()).Flags &
-                 MCFixupKindInfo::FKF_IsPCRel;
-
-  bool IsResolved = false;
-  if (IsPCRel) {
-    if (Target.getSymB()) {
-      IsResolved = false;
-    } else if (!Target.getSymA()) {
-      IsResolved = false;
-    } else {
-      const MCSymbolRefExpr *A = Target.getSymA();
-      const MCSymbol &SA = A->getSymbol();
-      if (A->getKind() != MCSymbolRefExpr::VK_None || SA.isUndefined()) {
-        IsResolved = false;
-      } else if (auto *Writer = getWriterPtr()) {
-        IsResolved = Writer->isSymbolRefDifferenceFullyResolvedImpl(
-            *this, SA, *DF, false, true);
-      }
-    }
-  } else {
-    IsResolved = Target.isAbsolute();
-  }
-
-  Value = Target.getConstant();
-
-  if (const MCSymbolRefExpr *A = Target.getSymA()) {
-    const MCSymbol &Sym = A->getSymbol();
-    if (Sym.isDefined())
-      Value += Layout.getSymbolOffset(Sym);
-  }
-  if (const MCSymbolRefExpr *B = Target.getSymB()) {
-    const MCSymbol &Sym = B->getSymbol();
-    if (Sym.isDefined())
-      Value -= Layout.getSymbolOffset(Sym);
-  }
-
-  bool ShouldAlignPC = getBackend().getFixupKindInfo(Fixup.getKind()).Flags &
-                       MCFixupKindInfo::FKF_IsAlignedDownTo32Bits;
-  assert((ShouldAlignPC ? IsPCRel : true) &&
-    "FKF_IsAlignedDownTo32Bits is only allowed on PC-relative fixups!");
-
-  if (IsPCRel) {
-    uint32_t Offset = Layout.getFragmentOffset(DF) + Fixup.getOffset();
-
-    // A number of ARM fixups in Thumb mode require that the effective PC
-    // address be determined as the 32-bit aligned version of the actual offset.
-    if (ShouldAlignPC) Offset &= ~0x3;
-    Value -= Offset;
-  }
-
-  // Let the backend force a relocation if needed.
-  if (IsResolved && getBackend().shouldForceRelocation(*this, Fixup, Target)) {
-    IsResolved = false;
-    WasForced = true;
-  }
-
-  return IsResolved;
-}
-
-uint64_t MCAssembler::computeFragmentSize(const MCAsmLayout &Layout,
-                                          const MCFragment &F) const {
-  assert(getBackendPtr() && "Requires assembler backend");
-  switch (F.getKind()) {
-  case MCFragment::FT_Data:
-    return cast<MCDataFragment>(F).getContents().size();
-  case MCFragment::FT_Relaxable:
-    return cast<MCRelaxableFragment>(F).getContents().size();
-  case MCFragment::FT_CompactEncodedInst:
-    return cast<MCCompactEncodedInstFragment>(F).getContents().size();
-  case MCFragment::FT_Fill: {
-    auto &FF = cast<MCFillFragment>(F);
-    int64_t NumValues = 0;
-    if (!FF.getNumValues().evaluateAsAbsolute(NumValues, Layout)) {
-      getContext().reportError(FF.getLoc(),
-                               "expected assembly-time absolute expression");
-      return 0;
-    }
-    int64_t Size = NumValues * FF.getValueSize();
-    if (Size < 0) {
-      getContext().reportError(FF.getLoc(), "invalid number of bytes");
-      return 0;
-    }
-    return Size;
-  }
-
-  case MCFragment::FT_LEB:
-    return cast<MCLEBFragment>(F).getContents().size();
-
-  case MCFragment::FT_Padding:
-    return cast<MCPaddingFragment>(F).getSize();
-
-  case MCFragment::FT_SymbolId:
-    return 4;
-
-  case MCFragment::FT_Align: {
-    const MCAlignFragment &AF = cast<MCAlignFragment>(F);
-    unsigned Offset = Layout.getFragmentOffset(&AF);
-    unsigned Size = OffsetToAlignment(Offset, AF.getAlignment());
-
-    // Insert extra Nops for code alignment if the target define
-    // shouldInsertExtraNopBytesForCodeAlign target hook.
-    if (AF.getParent()->UseCodeAlign() && AF.hasEmitNops() &&
-        getBackend().shouldInsertExtraNopBytesForCodeAlign(AF, Size))
-      return Size;
-
-    // If we are padding with nops, force the padding to be larger than the
-    // minimum nop size.
-    if (Size > 0 && AF.hasEmitNops()) {
-      while (Size % getBackend().getMinimumNopSize())
-        Size += AF.getAlignment();
-    }
-    if (Size > AF.getMaxBytesToEmit())
-      return 0;
-    return Size;
-  }
-
-  case MCFragment::FT_Org: {
-    const MCOrgFragment &OF = cast<MCOrgFragment>(F);
-    MCValue Value;
-    if (!OF.getOffset().evaluateAsValue(Value, Layout)) {
-      getContext().reportError(OF.getLoc(),
-                               "expected assembly-time absolute expression");
-        return 0;
-    }
-
-    uint64_t FragmentOffset = Layout.getFragmentOffset(&OF);
-    int64_t TargetLocation = Value.getConstant();
-    if (const MCSymbolRefExpr *A = Value.getSymA()) {
-      uint64_t Val;
-      if (!Layout.getSymbolOffset(A->getSymbol(), Val)) {
-        getContext().reportError(OF.getLoc(), "expected absolute expression");
-        return 0;
-      }
-      TargetLocation += Val;
-    }
-    int64_t Size = TargetLocation - FragmentOffset;
-    if (Size < 0 || Size >= 0x40000000) {
-      getContext().reportError(
-          OF.getLoc(), "invalid .org offset '" + Twine(TargetLocation) +
-                           "' (at offset '" + Twine(FragmentOffset) + "')");
-      return 0;
-    }
-    return Size;
-  }
-
-  case MCFragment::FT_Dwarf:
-    return cast<MCDwarfLineAddrFragment>(F).getContents().size();
-  case MCFragment::FT_DwarfFrame:
-    return cast<MCDwarfCallFrameFragment>(F).getContents().size();
-  case MCFragment::FT_CVInlineLines:
-    return cast<MCCVInlineLineTableFragment>(F).getContents().size();
-  case MCFragment::FT_CVDefRange:
-    return cast<MCCVDefRangeFragment>(F).getContents().size();
-  case MCFragment::FT_Dummy:
-    llvm_unreachable("Should not have been added");
-  }
-
-  llvm_unreachable("invalid fragment kind");
-}
-
-void MCAsmLayout::layoutFragment(MCFragment *F) {
-  MCFragment *Prev = F->getPrevNode();
-
-  // We should never try to recompute something which is valid.
-  assert(!isFragmentValid(F) && "Attempt to recompute a valid fragment!");
-  // We should never try to compute the fragment layout if its predecessor
-  // isn't valid.
-  assert((!Prev || isFragmentValid(Prev)) &&
-         "Attempt to compute fragment before its predecessor!");
-
-  ++stats::FragmentLayouts;
-
-  // Compute fragment offset and size.
-  if (Prev)
-    F->Offset = Prev->Offset + getAssembler().computeFragmentSize(*this, *Prev);
-  else
-    F->Offset = 0;
-  LastValidFragment[F->getParent()] = F;
-
-  // If bundling is enabled and this fragment has instructions in it, it has to
-  // obey the bundling restrictions. With padding, we'll have:
-  //
-  //
-  //        BundlePadding
-  //             |||
-  // -------------------------------------
-  //   Prev  |##########|       F        |
-  // -------------------------------------
-  //                    ^
-  //                    |
-  //                    F->Offset
-  //
-  // The fragment's offset will point to after the padding, and its computed
-  // size won't include the padding.
-  //
-  // When the -mc-relax-all flag is used, we optimize bundling by writting the
-  // padding directly into fragments when the instructions are emitted inside
-  // the streamer. When the fragment is larger than the bundle size, we need to
-  // ensure that it's bundle aligned. This means that if we end up with
-  // multiple fragments, we must emit bundle padding between fragments.
-  //
-  // ".align N" is an example of a directive that introduces multiple
-  // fragments. We could add a special case to handle ".align N" by emitting
-  // within-fragment padding (which would produce less padding when N is less
-  // than the bundle size), but for now we don't.
-  //
-  if (Assembler.isBundlingEnabled() && F->hasInstructions()) {
-    assert(isa<MCEncodedFragment>(F) &&
-           "Only MCEncodedFragment implementations have instructions");
-    MCEncodedFragment *EF = cast<MCEncodedFragment>(F);
-    uint64_t FSize = Assembler.computeFragmentSize(*this, *EF);
-
-    if (!Assembler.getRelaxAll() && FSize > Assembler.getBundleAlignSize())
-      report_fatal_error("Fragment can't be larger than a bundle size");
-
-    uint64_t RequiredBundlePadding =
-        computeBundlePadding(Assembler, EF, EF->Offset, FSize);
-    if (RequiredBundlePadding > UINT8_MAX)
-      report_fatal_error("Padding cannot exceed 255 bytes");
-    EF->setBundlePadding(static_cast<uint8_t>(RequiredBundlePadding));
-    EF->Offset += RequiredBundlePadding;
-  }
-}
-
-void MCAssembler::registerSymbol(const MCSymbol &Symbol, bool *Created) {
-  bool New = !Symbol.isRegistered();
-  if (Created)
-    *Created = New;
-  if (New) {
-    Symbol.setIsRegistered(true);
-    Symbols.push_back(&Symbol);
-  }
-}
-
-void MCAssembler::writeFragmentPadding(raw_ostream &OS,
-                                       const MCEncodedFragment &EF,
-                                       uint64_t FSize) const {
-  assert(getBackendPtr() && "Expected assembler backend");
-  // Should NOP padding be written out before this fragment?
-  unsigned BundlePadding = EF.getBundlePadding();
-  if (BundlePadding > 0) {
-    assert(isBundlingEnabled() &&
-           "Writing bundle padding with disabled bundling");
-    assert(EF.hasInstructions() &&
-           "Writing bundle padding for a fragment without instructions");
-
-    unsigned TotalLength = BundlePadding + static_cast<unsigned>(FSize);
-    if (EF.alignToBundleEnd() && TotalLength > getBundleAlignSize()) {
-      // If the padding itself crosses a bundle boundary, it must be emitted
-      // in 2 pieces, since even nop instructions must not cross boundaries.
-      //             v--------------v   <- BundleAlignSize
-      //        v---------v             <- BundlePadding
-      // ----------------------------
-      // | Prev |####|####|    F    |
-      // ----------------------------
-      //        ^-------------------^   <- TotalLength
-      unsigned DistanceToBoundary = TotalLength - getBundleAlignSize();
-      if (!getBackend().writeNopData(OS, DistanceToBoundary))
-        report_fatal_error("unable to write NOP sequence of " +
-                           Twine(DistanceToBoundary) + " bytes");
-      BundlePadding -= DistanceToBoundary;
-    }
-    if (!getBackend().writeNopData(OS, BundlePadding))
-      report_fatal_error("unable to write NOP sequence of " +
-                         Twine(BundlePadding) + " bytes");
-  }
-}
-
-/// Write the fragment \p F to the output file.
-static void writeFragment(raw_ostream &OS, const MCAssembler &Asm,
-                          const MCAsmLayout &Layout, const MCFragment &F) {
-  // FIXME: Embed in fragments instead?
-  uint64_t FragmentSize = Asm.computeFragmentSize(Layout, F);
-
-  support::endianness Endian = Asm.getBackend().Endian;
-
-  if (const MCEncodedFragment *EF = dyn_cast<MCEncodedFragment>(&F))
-    Asm.writeFragmentPadding(OS, *EF, FragmentSize);
-
-  // This variable (and its dummy usage) is to participate in the assert at
-  // the end of the function.
-  uint64_t Start = OS.tell();
-  (void) Start;
-
-  ++stats::EmittedFragments;
-
-  switch (F.getKind()) {
-  case MCFragment::FT_Align: {
-    ++stats::EmittedAlignFragments;
-    const MCAlignFragment &AF = cast<MCAlignFragment>(F);
-    assert(AF.getValueSize() && "Invalid virtual align in concrete fragment!");
-
-    uint64_t Count = FragmentSize / AF.getValueSize();
-
-    // FIXME: This error shouldn't actually occur (the front end should emit
-    // multiple .align directives to enforce the semantics it wants), but is
-    // severe enough that we want to report it. How to handle this?
-    if (Count * AF.getValueSize() != FragmentSize)
-      report_fatal_error("undefined .align directive, value size '" +
-                        Twine(AF.getValueSize()) +
-                        "' is not a divisor of padding size '" +
-                        Twine(FragmentSize) + "'");
-
-    // See if we are aligning with nops, and if so do that first to try to fill
-    // the Count bytes.  Then if that did not fill any bytes or there are any
-    // bytes left to fill use the Value and ValueSize to fill the rest.
-    // If we are aligning with nops, ask that target to emit the right data.
-    if (AF.hasEmitNops()) {
-      if (!Asm.getBackend().writeNopData(OS, Count))
-        report_fatal_error("unable to write nop sequence of " +
-                          Twine(Count) + " bytes");
-      break;
-    }
-
-    // Otherwise, write out in multiples of the value size.
-    for (uint64_t i = 0; i != Count; ++i) {
-      switch (AF.getValueSize()) {
-      default: llvm_unreachable("Invalid size!");
-      case 1: OS << char(AF.getValue()); break;
-      case 2:
-        support::endian::write<uint16_t>(OS, AF.getValue(), Endian);
-        break;
-      case 4:
-        support::endian::write<uint32_t>(OS, AF.getValue(), Endian);
-        break;
-      case 8:
-        support::endian::write<uint64_t>(OS, AF.getValue(), Endian);
-        break;
-      }
-    }
-    break;
-  }
-
-  case MCFragment::FT_Data:
-    ++stats::EmittedDataFragments;
-    OS << cast<MCDataFragment>(F).getContents();
-    break;
-
-  case MCFragment::FT_Relaxable:
-    ++stats::EmittedRelaxableFragments;
-    OS << cast<MCRelaxableFragment>(F).getContents();
-    break;
-
-  case MCFragment::FT_CompactEncodedInst:
-    ++stats::EmittedCompactEncodedInstFragments;
-    OS << cast<MCCompactEncodedInstFragment>(F).getContents();
-    break;
-
-  case MCFragment::FT_Fill: {
-    ++stats::EmittedFillFragments;
-    const MCFillFragment &FF = cast<MCFillFragment>(F);
-    uint64_t V = FF.getValue();
-    unsigned VSize = FF.getValueSize();
-    const unsigned MaxChunkSize = 16;
-    char Data[MaxChunkSize];
-    // Duplicate V into Data as byte vector to reduce number of
-    // writes done. As such, do endian conversion here.
-    for (unsigned I = 0; I != VSize; ++I) {
-      unsigned index = Endian == support::little ? I : (VSize - I - 1);
-      Data[I] = uint8_t(V >> (index * 8));
-    }
-    for (unsigned I = VSize; I < MaxChunkSize; ++I)
-      Data[I] = Data[I - VSize];
-
-    // Set to largest multiple of VSize in Data.
-    const unsigned NumPerChunk = MaxChunkSize / VSize;
-    // Set ChunkSize to largest multiple of VSize in Data
-    const unsigned ChunkSize = VSize * NumPerChunk;
-
-    // Do copies by chunk.
-    StringRef Ref(Data, ChunkSize);
-    for (uint64_t I = 0, E = FragmentSize / ChunkSize; I != E; ++I)
-      OS << Ref;
-
-    // do remainder if needed.
-    unsigned TrailingCount = FragmentSize % ChunkSize;
-    if (TrailingCount)
-      OS.write(Data, TrailingCount);
-    break;
-  }
-
-  case MCFragment::FT_LEB: {
-    const MCLEBFragment &LF = cast<MCLEBFragment>(F);
-    OS << LF.getContents();
-    break;
-  }
-
-  case MCFragment::FT_Padding: {
-    if (!Asm.getBackend().writeNopData(OS, FragmentSize))
-      report_fatal_error("unable to write nop sequence of " +
-                         Twine(FragmentSize) + " bytes");
-    break;
-  }
-
-  case MCFragment::FT_SymbolId: {
-    const MCSymbolIdFragment &SF = cast<MCSymbolIdFragment>(F);
-    support::endian::write<uint32_t>(OS, SF.getSymbol()->getIndex(), Endian);
-    break;
-  }
-
-  case MCFragment::FT_Org: {
-    ++stats::EmittedOrgFragments;
-    const MCOrgFragment &OF = cast<MCOrgFragment>(F);
-
-    for (uint64_t i = 0, e = FragmentSize; i != e; ++i)
-      OS << char(OF.getValue());
-
-    break;
-  }
-
-  case MCFragment::FT_Dwarf: {
-    const MCDwarfLineAddrFragment &OF = cast<MCDwarfLineAddrFragment>(F);
-    OS << OF.getContents();
-    break;
-  }
-  case MCFragment::FT_DwarfFrame: {
-    const MCDwarfCallFrameFragment &CF = cast<MCDwarfCallFrameFragment>(F);
-    OS << CF.getContents();
-    break;
-  }
-  case MCFragment::FT_CVInlineLines: {
-    const auto &OF = cast<MCCVInlineLineTableFragment>(F);
-    OS << OF.getContents();
-    break;
-  }
-  case MCFragment::FT_CVDefRange: {
-    const auto &DRF = cast<MCCVDefRangeFragment>(F);
-    OS << DRF.getContents();
-    break;
-  }
-  case MCFragment::FT_Dummy:
-    llvm_unreachable("Should not have been added");
-  }
-
-  assert(OS.tell() - Start == FragmentSize &&
-         "The stream should advance by fragment size");
-}
-
-void MCAssembler::writeSectionData(raw_ostream &OS, const MCSection *Sec,
-                                   const MCAsmLayout &Layout) const {
-  assert(getBackendPtr() && "Expected assembler backend");
-
-  // Ignore virtual sections.
-  if (Sec->isVirtualSection()) {
-    assert(Layout.getSectionFileSize(Sec) == 0 && "Invalid size for section!");
-
-    // Check that contents are only things legal inside a virtual section.
-    for (const MCFragment &F : *Sec) {
-      switch (F.getKind()) {
-      default: llvm_unreachable("Invalid fragment in virtual section!");
-      case MCFragment::FT_Data: {
-        // Check that we aren't trying to write a non-zero contents (or fixups)
-        // into a virtual section. This is to support clients which use standard
-        // directives to fill the contents of virtual sections.
-        const MCDataFragment &DF = cast<MCDataFragment>(F);
-        if (DF.fixup_begin() != DF.fixup_end())
-          report_fatal_error("cannot have fixups in virtual section!");
-        for (unsigned i = 0, e = DF.getContents().size(); i != e; ++i)
-          if (DF.getContents()[i]) {
-            if (auto *ELFSec = dyn_cast<const MCSectionELF>(Sec))
-              report_fatal_error("non-zero initializer found in section '" +
-                  ELFSec->getSectionName() + "'");
-            else
-              report_fatal_error("non-zero initializer found in virtual section");
-          }
-        break;
-      }
-      case MCFragment::FT_Align:
-        // Check that we aren't trying to write a non-zero value into a virtual
-        // section.
-        assert((cast<MCAlignFragment>(F).getValueSize() == 0 ||
-                cast<MCAlignFragment>(F).getValue() == 0) &&
-               "Invalid align in virtual section!");
-        break;
-      case MCFragment::FT_Fill:
-        assert((cast<MCFillFragment>(F).getValue() == 0) &&
-               "Invalid fill in virtual section!");
-        break;
-      }
-    }
-
-    return;
-  }
-
-  uint64_t Start = OS.tell();
-  (void)Start;
-
-  for (const MCFragment &F : *Sec)
-    writeFragment(OS, *this, Layout, F);
-
-  assert(OS.tell() - Start == Layout.getSectionAddressSize(Sec));
-}
-
-std::tuple<MCValue, uint64_t, bool>
-MCAssembler::handleFixup(const MCAsmLayout &Layout, MCFragment &F,
-                         const MCFixup &Fixup) {
-  // Evaluate the fixup.
-  MCValue Target;
-  uint64_t FixedValue;
-  bool WasForced;
-  bool IsResolved = evaluateFixup(Layout, Fixup, &F, Target, FixedValue,
-                                  WasForced);
-  if (!IsResolved) {
-    // The fixup was unresolved, we need a relocation. Inform the object
-    // writer of the relocation, and give it an opportunity to adjust the
-    // fixup value if need be.
-    if (Target.getSymA() && Target.getSymB() &&
-        getBackend().requiresDiffExpressionRelocations()) {
-      // The fixup represents the difference between two symbols, which the
-      // backend has indicated must be resolved at link time. Split up the fixup
-      // into two relocations, one for the add, and one for the sub, and emit
-      // both of these. The constant will be associated with the add half of the
-      // expression.
-      MCFixup FixupAdd = MCFixup::createAddFor(Fixup);
-      MCValue TargetAdd =
-          MCValue::get(Target.getSymA(), nullptr, Target.getConstant());
-      getWriter().recordRelocation(*this, Layout, &F, FixupAdd, TargetAdd,
-                                   FixedValue);
-      MCFixup FixupSub = MCFixup::createSubFor(Fixup);
-      MCValue TargetSub = MCValue::get(Target.getSymB());
-      getWriter().recordRelocation(*this, Layout, &F, FixupSub, TargetSub,
-                                   FixedValue);
-    } else {
-      getWriter().recordRelocation(*this, Layout, &F, Fixup, Target,
-                                   FixedValue);
-    }
-  }
-  return std::make_tuple(Target, FixedValue, IsResolved);
-}
-
-void MCAssembler::layout(MCAsmLayout &Layout) {
-  assert(getBackendPtr() && "Expected assembler backend");
-  DEBUG_WITH_TYPE("mc-dump", {
-      errs() << "assembler backend - pre-layout\n--\n";
-      dump(); });
-
-  // Create dummy fragments and assign section ordinals.
-  unsigned SectionIndex = 0;
-  for (MCSection &Sec : *this) {
-    // Create dummy fragments to eliminate any empty sections, this simplifies
-    // layout.
-    if (Sec.getFragmentList().empty())
-      new MCDataFragment(&Sec);
-
-    Sec.setOrdinal(SectionIndex++);
-  }
-
-  // Assign layout order indices to sections and fragments.
-  for (unsigned i = 0, e = Layout.getSectionOrder().size(); i != e; ++i) {
-    MCSection *Sec = Layout.getSectionOrder()[i];
-    Sec->setLayoutOrder(i);
-
-    unsigned FragmentIndex = 0;
-    for (MCFragment &Frag : *Sec)
-      Frag.setLayoutOrder(FragmentIndex++);
-  }
-
-  // Layout until everything fits.
-  while (layoutOnce(Layout))
-    if (getContext().hadError())
-      return;
-
-  DEBUG_WITH_TYPE("mc-dump", {
-      errs() << "assembler backend - post-relaxation\n--\n";
-      dump(); });
-
-  // Finalize the layout, including fragment lowering.
-  finishLayout(Layout);
-
-  DEBUG_WITH_TYPE("mc-dump", {
-      errs() << "assembler backend - final-layout\n--\n";
-      dump(); });
-
-  // Allow the object writer a chance to perform post-layout binding (for
-  // example, to set the index fields in the symbol data).
-  getWriter().executePostLayoutBinding(*this, Layout);
-
-  // Evaluate and apply the fixups, generating relocation entries as necessary.
-  for (MCSection &Sec : *this) {
-    for (MCFragment &Frag : Sec) {
-      // Data and relaxable fragments both have fixups.  So only process
-      // those here.
-      // FIXME: Is there a better way to do this?  MCEncodedFragmentWithFixups
-      // being templated makes this tricky.
-      if (isa<MCEncodedFragment>(&Frag) &&
-          isa<MCCompactEncodedInstFragment>(&Frag))
-        continue;
-      if (!isa<MCEncodedFragment>(&Frag) && !isa<MCCVDefRangeFragment>(&Frag) &&
-          !isa<MCAlignFragment>(&Frag))
-        continue;
-      ArrayRef<MCFixup> Fixups;
-      MutableArrayRef<char> Contents;
-      const MCSubtargetInfo *STI = nullptr;
-      if (auto *FragWithFixups = dyn_cast<MCDataFragment>(&Frag)) {
-        Fixups = FragWithFixups->getFixups();
-        Contents = FragWithFixups->getContents();
-        STI = FragWithFixups->getSubtargetInfo();
-        assert(!FragWithFixups->hasInstructions() || STI != nullptr);
-      } else if (auto *FragWithFixups = dyn_cast<MCRelaxableFragment>(&Frag)) {
-        Fixups = FragWithFixups->getFixups();
-        Contents = FragWithFixups->getContents();
-        STI = FragWithFixups->getSubtargetInfo();
-        assert(!FragWithFixups->hasInstructions() || STI != nullptr);
-      } else if (auto *FragWithFixups = dyn_cast<MCCVDefRangeFragment>(&Frag)) {
-        Fixups = FragWithFixups->getFixups();
-        Contents = FragWithFixups->getContents();
-      } else if (auto *FragWithFixups = dyn_cast<MCDwarfLineAddrFragment>(&Frag)) {
-        Fixups = FragWithFixups->getFixups();
-        Contents = FragWithFixups->getContents();
-      } else if (auto *AF = dyn_cast<MCAlignFragment>(&Frag)) {
-        // Insert fixup type for code alignment if the target define
-        // shouldInsertFixupForCodeAlign target hook.
-        if (Sec.UseCodeAlign() && AF->hasEmitNops()) {
-          getBackend().shouldInsertFixupForCodeAlign(*this, Layout, *AF);
-        }
-        continue;
-      } else if (auto *FragWithFixups =
-                     dyn_cast<MCDwarfCallFrameFragment>(&Frag)) {
-        Fixups = FragWithFixups->getFixups();
-        Contents = FragWithFixups->getContents();
-      } else
-        llvm_unreachable("Unknown fragment with fixups!");
-      for (const MCFixup &Fixup : Fixups) {
-        uint64_t FixedValue;
-        bool IsResolved;
-        MCValue Target;
-        std::tie(Target, FixedValue, IsResolved) =
-            handleFixup(Layout, Frag, Fixup);
-        getBackend().applyFixup(*this, Fixup, Target, Contents, FixedValue,
-                                IsResolved, STI);
-      }
-    }
-  }
-}
-
-void MCAssembler::Finish() {
-  // Create the layout object.
-  MCAsmLayout Layout(*this);
-  layout(Layout);
-
-  // Write the object file.
-  stats::ObjectBytes += getWriter().writeObject(*this, Layout);
-}
-
-bool MCAssembler::fixupNeedsRelaxation(const MCFixup &Fixup,
-                                       const MCRelaxableFragment *DF,
-                                       const MCAsmLayout &Layout) const {
-  assert(getBackendPtr() && "Expected assembler backend");
-  MCValue Target;
-  uint64_t Value;
-  bool WasForced;
-  bool Resolved = evaluateFixup(Layout, Fixup, DF, Target, Value, WasForced);
-  if (Target.getSymA() &&
-      Target.getSymA()->getKind() == MCSymbolRefExpr::VK_X86_ABS8 &&
-      Fixup.getKind() == FK_Data_1)
-    return false;
-  return getBackend().fixupNeedsRelaxationAdvanced(Fixup, Resolved, Value, DF,
-                                                   Layout, WasForced);
-}
-
-bool MCAssembler::fragmentNeedsRelaxation(const MCRelaxableFragment *F,
-                                          const MCAsmLayout &Layout) const {
-  assert(getBackendPtr() && "Expected assembler backend");
-  // If this inst doesn't ever need relaxation, ignore it. This occurs when we
-  // are intentionally pushing out inst fragments, or because we relaxed a
-  // previous instruction to one that doesn't need relaxation.
-  if (!getBackend().mayNeedRelaxation(F->getInst(), *F->getSubtargetInfo()))
-    return false;
-
-  for (const MCFixup &Fixup : F->getFixups())
-    if (fixupNeedsRelaxation(Fixup, F, Layout))
-      return true;
-
-  return false;
-}
-
-bool MCAssembler::relaxInstruction(MCAsmLayout &Layout,
-                                   MCRelaxableFragment &F) {
-  assert(getEmitterPtr() &&
-         "Expected CodeEmitter defined for relaxInstruction");
-  if (!fragmentNeedsRelaxation(&F, Layout))
-    return false;
-
-  ++stats::RelaxedInstructions;
-
-  // FIXME-PERF: We could immediately lower out instructions if we can tell
-  // they are fully resolved, to avoid retesting on later passes.
-
-  // Relax the fragment.
-
-  MCInst Relaxed;
-  getBackend().relaxInstruction(F.getInst(), *F.getSubtargetInfo(), Relaxed);
-
-  // Encode the new instruction.
-  //
-  // FIXME-PERF: If it matters, we could let the target do this. It can
-  // probably do so more efficiently in many cases.
-  SmallVector<MCFixup, 4> Fixups;
-  SmallString<256> Code;
-  raw_svector_ostream VecOS(Code);
-  getEmitter().encodeInstruction(Relaxed, VecOS, Fixups, *F.getSubtargetInfo());
-
-  // Update the fragment.
-  F.setInst(Relaxed);
-  F.getContents() = Code;
-  F.getFixups() = Fixups;
-
-  return true;
-}
-
-bool MCAssembler::relaxPaddingFragment(MCAsmLayout &Layout,
-                                       MCPaddingFragment &PF) {
-  assert(getBackendPtr() && "Expected assembler backend");
-  uint64_t OldSize = PF.getSize();
-  if (!getBackend().relaxFragment(&PF, Layout))
-    return false;
-  uint64_t NewSize = PF.getSize();
-
-  ++stats::PaddingFragmentsRelaxations;
-  stats::PaddingFragmentsBytes += NewSize;
-  stats::PaddingFragmentsBytes -= OldSize;
-  return true;
-}
-
-bool MCAssembler::relaxLEB(MCAsmLayout &Layout, MCLEBFragment &LF) {
-  uint64_t OldSize = LF.getContents().size();
-  int64_t Value;
-  bool Abs = LF.getValue().evaluateKnownAbsolute(Value, Layout);
-  if (!Abs)
-    report_fatal_error("sleb128 and uleb128 expressions must be absolute");
-  SmallString<8> &Data = LF.getContents();
-  Data.clear();
-  raw_svector_ostream OSE(Data);
-  // The compiler can generate EH table assembly that is impossible to assemble
-  // without either adding padding to an LEB fragment or adding extra padding
-  // to a later alignment fragment. To accommodate such tables, relaxation can
-  // only increase an LEB fragment size here, not decrease it. See PR35809.
-  if (LF.isSigned())
-    encodeSLEB128(Value, OSE, OldSize);
-  else
-    encodeULEB128(Value, OSE, OldSize);
-  return OldSize != LF.getContents().size();
-}
-
-bool MCAssembler::relaxDwarfLineAddr(MCAsmLayout &Layout,
-                                     MCDwarfLineAddrFragment &DF) {
-  MCContext &Context = Layout.getAssembler().getContext();
-  uint64_t OldSize = DF.getContents().size();
-  int64_t AddrDelta;
-  bool Abs = DF.getAddrDelta().evaluateKnownAbsolute(AddrDelta, Layout);
-  assert(Abs && "We created a line delta with an invalid expression");
-  (void)Abs;
-  int64_t LineDelta;
-  LineDelta = DF.getLineDelta();
-  SmallVectorImpl<char> &Data = DF.getContents();
-  Data.clear();
-  raw_svector_ostream OSE(Data);
-  DF.getFixups().clear();
-
-  if (!getBackend().requiresDiffExpressionRelocations()) {
-    MCDwarfLineAddr::Encode(Context, getDWARFLinetableParams(), LineDelta,
-                            AddrDelta, OSE);
-  } else {
-    uint32_t Offset;
-    uint32_t Size;
-    bool SetDelta = MCDwarfLineAddr::FixedEncode(Context,
-                                                 getDWARFLinetableParams(),
-                                                 LineDelta, AddrDelta,
-                                                 OSE, &Offset, &Size);
-    // Add Fixups for address delta or new address.
-    const MCExpr *FixupExpr;
-    if (SetDelta) {
-      FixupExpr = &DF.getAddrDelta();
-    } else {
-      const MCBinaryExpr *ABE = cast<MCBinaryExpr>(&DF.getAddrDelta());
-      FixupExpr = ABE->getLHS();
-    }
-    DF.getFixups().push_back(
-        MCFixup::create(Offset, FixupExpr,
-                        MCFixup::getKindForSize(Size, false /*isPCRel*/)));
-  }
-
-  return OldSize != Data.size();
-}
-
-bool MCAssembler::relaxDwarfCallFrameFragment(MCAsmLayout &Layout,
-                                              MCDwarfCallFrameFragment &DF) {
-  MCContext &Context = Layout.getAssembler().getContext();
-  uint64_t OldSize = DF.getContents().size();
-  int64_t AddrDelta;
-  bool Abs = DF.getAddrDelta().evaluateKnownAbsolute(AddrDelta, Layout);
-  assert(Abs && "We created call frame with an invalid expression");
-  (void) Abs;
-  SmallVectorImpl<char> &Data = DF.getContents();
-  Data.clear();
-  raw_svector_ostream OSE(Data);
-  DF.getFixups().clear();
-
-  if (getBackend().requiresDiffExpressionRelocations()) {
-    uint32_t Offset;
-    uint32_t Size;
-    MCDwarfFrameEmitter::EncodeAdvanceLoc(Context, AddrDelta, OSE, &Offset,
-                                          &Size);
-    if (Size) {
-      DF.getFixups().push_back(MCFixup::create(
-          Offset, &DF.getAddrDelta(),
-          MCFixup::getKindForSizeInBits(Size /*In bits.*/, false /*isPCRel*/)));
-    }
-  } else {
-    MCDwarfFrameEmitter::EncodeAdvanceLoc(Context, AddrDelta, OSE);
-  }
-
-  return OldSize != Data.size();
-}
-
-bool MCAssembler::relaxCVInlineLineTable(MCAsmLayout &Layout,
-                                         MCCVInlineLineTableFragment &F) {
-  unsigned OldSize = F.getContents().size();
-  getContext().getCVContext().encodeInlineLineTable(Layout, F);
-  return OldSize != F.getContents().size();
-}
-
-bool MCAssembler::relaxCVDefRange(MCAsmLayout &Layout,
-                                  MCCVDefRangeFragment &F) {
-  unsigned OldSize = F.getContents().size();
-  getContext().getCVContext().encodeDefRange(Layout, F);
-  return OldSize != F.getContents().size();
-}
-
-bool MCAssembler::layoutSectionOnce(MCAsmLayout &Layout, MCSection &Sec) {
-  // Holds the first fragment which needed relaxing during this layout. It will
-  // remain NULL if none were relaxed.
-  // When a fragment is relaxed, all the fragments following it should get
-  // invalidated because their offset is going to change.
-  MCFragment *FirstRelaxedFragment = nullptr;
-
-  // Attempt to relax all the fragments in the section.
-  for (MCSection::iterator I = Sec.begin(), IE = Sec.end(); I != IE; ++I) {
-    // Check if this is a fragment that needs relaxation.
-    bool RelaxedFrag = false;
-    switch(I->getKind()) {
-    default:
-      break;
-    case MCFragment::FT_Relaxable:
-      assert(!getRelaxAll() &&
-             "Did not expect a MCRelaxableFragment in RelaxAll mode");
-      RelaxedFrag = relaxInstruction(Layout, *cast<MCRelaxableFragment>(I));
-      break;
-    case MCFragment::FT_Dwarf:
-      RelaxedFrag = relaxDwarfLineAddr(Layout,
-                                       *cast<MCDwarfLineAddrFragment>(I));
-      break;
-    case MCFragment::FT_DwarfFrame:
-      RelaxedFrag =
-        relaxDwarfCallFrameFragment(Layout,
-                                    *cast<MCDwarfCallFrameFragment>(I));
-      break;
-    case MCFragment::FT_LEB:
-      RelaxedFrag = relaxLEB(Layout, *cast<MCLEBFragment>(I));
-      break;
-    case MCFragment::FT_Padding:
-      RelaxedFrag = relaxPaddingFragment(Layout, *cast<MCPaddingFragment>(I));
-      break;
-    case MCFragment::FT_CVInlineLines:
-      RelaxedFrag =
-          relaxCVInlineLineTable(Layout, *cast<MCCVInlineLineTableFragment>(I));
-      break;
-    case MCFragment::FT_CVDefRange:
-      RelaxedFrag = relaxCVDefRange(Layout, *cast<MCCVDefRangeFragment>(I));
-      break;
-    }
-    if (RelaxedFrag && !FirstRelaxedFragment)
-      FirstRelaxedFragment = &*I;
-  }
-  if (FirstRelaxedFragment) {
-    Layout.invalidateFragmentsFrom(FirstRelaxedFragment);
-    return true;
-  }
-  return false;
-}
-
-bool MCAssembler::layoutOnce(MCAsmLayout &Layout) {
-  ++stats::RelaxationSteps;
-
-  bool WasRelaxed = false;
-  for (iterator it = begin(), ie = end(); it != ie; ++it) {
-    MCSection &Sec = *it;
-    while (layoutSectionOnce(Layout, Sec))
-      WasRelaxed = true;
-  }
-
-  return WasRelaxed;
-}
-
-void MCAssembler::finishLayout(MCAsmLayout &Layout) {
-  assert(getBackendPtr() && "Expected assembler backend");
-  // The layout is done. Mark every fragment as valid.
-  for (unsigned int i = 0, n = Layout.getSectionOrder().size(); i != n; ++i) {
-    MCSection &Section = *Layout.getSectionOrder()[i];
-    Layout.getFragmentOffset(&*Section.rbegin());
-    computeFragmentSize(Layout, *Section.rbegin());
-  }
-  getBackend().finishLayout(*this, Layout);
-}
-
-#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
-LLVM_DUMP_METHOD void MCAssembler::dump() const{
-  raw_ostream &OS = errs();
-
-  OS << "<MCAssembler\n";
-  OS << "  Sections:[\n    ";
-  for (const_iterator it = begin(), ie = end(); it != ie; ++it) {
-    if (it != begin()) OS << ",\n    ";
-    it->dump();
-  }
-  OS << "],\n";
-  OS << "  Symbols:[";
-
-  for (const_symbol_iterator it = symbol_begin(), ie = symbol_end(); it != ie; ++it) {
-    if (it != symbol_begin()) OS << ",\n           ";
-    OS << "(";
-    it->dump();
-    OS << ", Index:" << it->getIndex() << ", ";
-    OS << ")";
-  }
-  OS << "]>\n";
-}
-#endif