YQ Connector: support managed ClickHouse

Со стороны dqrun можно обратиться к инстансу коннектора, который работает на streaming стенде, и извлечь данные из облачного CH.

1 files changed, 1996 insertions, 0 deletions

diff --git a/contrib/libs/llvm16/lib/Object/WasmObjectFile.cpp b/contrib/libs/llvm16/lib/Object/WasmObjectFile.cpp
new file mode 100644
index 0000000000..1e98de7cd4
--- /dev/null
+++ b/contrib/libs/llvm16/lib/Object/WasmObjectFile.cpp
@@ -0,0 +1,1996 @@
+//===- WasmObjectFile.cpp - Wasm object file 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/ADT/ArrayRef.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/StringSet.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/BinaryFormat/Wasm.h"
+#include "llvm/MC/SubtargetFeature.h"
+#include "llvm/Object/Binary.h"
+#include "llvm/Object/Error.h"
+#include "llvm/Object/ObjectFile.h"
+#include "llvm/Object/SymbolicFile.h"
+#include "llvm/Object/Wasm.h"
+#include "llvm/Support/Endian.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/LEB128.h"
+#include "llvm/Support/ScopedPrinter.h"
+#include <algorithm>
+#include <cassert>
+#include <cstdint>
+#include <cstring>
+
+#define DEBUG_TYPE "wasm-object"
+
+using namespace llvm;
+using namespace object;
+
+void WasmSymbol::print(raw_ostream &Out) const {
+  Out << "Name=" << Info.Name
+      << ", Kind=" << toString(wasm::WasmSymbolType(Info.Kind)) << ", Flags=0x"
+      << Twine::utohexstr(Info.Flags);
+  if (!isTypeData()) {
+    Out << ", ElemIndex=" << Info.ElementIndex;
+  } else if (isDefined()) {
+    Out << ", Segment=" << Info.DataRef.Segment;
+    Out << ", Offset=" << Info.DataRef.Offset;
+    Out << ", Size=" << Info.DataRef.Size;
+  }
+}
+
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
+LLVM_DUMP_METHOD void WasmSymbol::dump() const { print(dbgs()); }
+#endif
+
+Expected<std::unique_ptr<WasmObjectFile>>
+ObjectFile::createWasmObjectFile(MemoryBufferRef Buffer) {
+  Error Err = Error::success();
+  auto ObjectFile = std::make_unique<WasmObjectFile>(Buffer, Err);
+  if (Err)
+    return std::move(Err);
+
+  return std::move(ObjectFile);
+}
+
+#define VARINT7_MAX ((1 << 7) - 1)
+#define VARINT7_MIN (-(1 << 7))
+#define VARUINT7_MAX (1 << 7)
+#define VARUINT1_MAX (1)
+
+static uint8_t readUint8(WasmObjectFile::ReadContext &Ctx) {
+  if (Ctx.Ptr == Ctx.End)
+    report_fatal_error("EOF while reading uint8");
+  return *Ctx.Ptr++;
+}
+
+static uint32_t readUint32(WasmObjectFile::ReadContext &Ctx) {
+  if (Ctx.Ptr + 4 > Ctx.End)
+    report_fatal_error("EOF while reading uint32");
+  uint32_t Result = support::endian::read32le(Ctx.Ptr);
+  Ctx.Ptr += 4;
+  return Result;
+}
+
+static int32_t readFloat32(WasmObjectFile::ReadContext &Ctx) {
+  if (Ctx.Ptr + 4 > Ctx.End)
+    report_fatal_error("EOF while reading float64");
+  int32_t Result = 0;
+  memcpy(&Result, Ctx.Ptr, sizeof(Result));
+  Ctx.Ptr += sizeof(Result);
+  return Result;
+}
+
+static int64_t readFloat64(WasmObjectFile::ReadContext &Ctx) {
+  if (Ctx.Ptr + 8 > Ctx.End)
+    report_fatal_error("EOF while reading float64");
+  int64_t Result = 0;
+  memcpy(&Result, Ctx.Ptr, sizeof(Result));
+  Ctx.Ptr += sizeof(Result);
+  return Result;
+}
+
+static uint64_t readULEB128(WasmObjectFile::ReadContext &Ctx) {
+  unsigned Count;
+  const char *Error = nullptr;
+  uint64_t Result = decodeULEB128(Ctx.Ptr, &Count, Ctx.End, &Error);
+  if (Error)
+    report_fatal_error(Error);
+  Ctx.Ptr += Count;
+  return Result;
+}
+
+static StringRef readString(WasmObjectFile::ReadContext &Ctx) {
+  uint32_t StringLen = readULEB128(Ctx);
+  if (Ctx.Ptr + StringLen > Ctx.End)
+    report_fatal_error("EOF while reading string");
+  StringRef Return =
+      StringRef(reinterpret_cast<const char *>(Ctx.Ptr), StringLen);
+  Ctx.Ptr += StringLen;
+  return Return;
+}
+
+static int64_t readLEB128(WasmObjectFile::ReadContext &Ctx) {
+  unsigned Count;
+  const char *Error = nullptr;
+  uint64_t Result = decodeSLEB128(Ctx.Ptr, &Count, Ctx.End, &Error);
+  if (Error)
+    report_fatal_error(Error);
+  Ctx.Ptr += Count;
+  return Result;
+}
+
+static uint8_t readVaruint1(WasmObjectFile::ReadContext &Ctx) {
+  int64_t Result = readLEB128(Ctx);
+  if (Result > VARUINT1_MAX || Result < 0)
+    report_fatal_error("LEB is outside Varuint1 range");
+  return Result;
+}
+
+static int32_t readVarint32(WasmObjectFile::ReadContext &Ctx) {
+  int64_t Result = readLEB128(Ctx);
+  if (Result > INT32_MAX || Result < INT32_MIN)
+    report_fatal_error("LEB is outside Varint32 range");
+  return Result;
+}
+
+static uint32_t readVaruint32(WasmObjectFile::ReadContext &Ctx) {
+  uint64_t Result = readULEB128(Ctx);
+  if (Result > UINT32_MAX)
+    report_fatal_error("LEB is outside Varuint32 range");
+  return Result;
+}
+
+static int64_t readVarint64(WasmObjectFile::ReadContext &Ctx) {
+  return readLEB128(Ctx);
+}
+
+static uint64_t readVaruint64(WasmObjectFile::ReadContext &Ctx) {
+  return readULEB128(Ctx);
+}
+
+static uint8_t readOpcode(WasmObjectFile::ReadContext &Ctx) {
+  return readUint8(Ctx);
+}
+
+static Error readInitExpr(wasm::WasmInitExpr &Expr,
+                          WasmObjectFile::ReadContext &Ctx) {
+  auto Start = Ctx.Ptr;
+
+  Expr.Extended = false;
+  Expr.Inst.Opcode = readOpcode(Ctx);
+  switch (Expr.Inst.Opcode) {
+  case wasm::WASM_OPCODE_I32_CONST:
+    Expr.Inst.Value.Int32 = readVarint32(Ctx);
+    break;
+  case wasm::WASM_OPCODE_I64_CONST:
+    Expr.Inst.Value.Int64 = readVarint64(Ctx);
+    break;
+  case wasm::WASM_OPCODE_F32_CONST:
+    Expr.Inst.Value.Float32 = readFloat32(Ctx);
+    break;
+  case wasm::WASM_OPCODE_F64_CONST:
+    Expr.Inst.Value.Float64 = readFloat64(Ctx);
+    break;
+  case wasm::WASM_OPCODE_GLOBAL_GET:
+    Expr.Inst.Value.Global = readULEB128(Ctx);
+    break;
+  case wasm::WASM_OPCODE_REF_NULL: {
+    wasm::ValType Ty = static_cast<wasm::ValType>(readULEB128(Ctx));
+    if (Ty != wasm::ValType::EXTERNREF) {
+      return make_error<GenericBinaryError>("invalid type for ref.null",
+                                            object_error::parse_failed);
+    }
+    break;
+  }
+  default:
+    Expr.Extended = true;
+  }
+
+  if (!Expr.Extended) {
+    uint8_t EndOpcode = readOpcode(Ctx);
+    if (EndOpcode != wasm::WASM_OPCODE_END)
+      Expr.Extended = true;
+  }
+
+  if (Expr.Extended) {
+    Ctx.Ptr = Start;
+    while (true) {
+      uint8_t Opcode = readOpcode(Ctx);
+      switch (Opcode) {
+      case wasm::WASM_OPCODE_I32_CONST:
+      case wasm::WASM_OPCODE_GLOBAL_GET:
+      case wasm::WASM_OPCODE_REF_NULL:
+      case wasm::WASM_OPCODE_I64_CONST:
+      case wasm::WASM_OPCODE_F32_CONST:
+      case wasm::WASM_OPCODE_F64_CONST:
+        readULEB128(Ctx);
+        break;
+      case wasm::WASM_OPCODE_I32_ADD:
+      case wasm::WASM_OPCODE_I32_SUB:
+      case wasm::WASM_OPCODE_I32_MUL:
+      case wasm::WASM_OPCODE_I64_ADD:
+      case wasm::WASM_OPCODE_I64_SUB:
+      case wasm::WASM_OPCODE_I64_MUL:
+        break;
+      case wasm::WASM_OPCODE_END:
+        Expr.Body = ArrayRef<uint8_t>(Start, Ctx.Ptr - Start);
+        return Error::success();
+      default:
+        return make_error<GenericBinaryError>(
+            Twine("invalid opcode in init_expr: ") + Twine(unsigned(Opcode)),
+            object_error::parse_failed);
+      }
+    }
+  }
+
+  return Error::success();
+}
+
+static wasm::WasmLimits readLimits(WasmObjectFile::ReadContext &Ctx) {
+  wasm::WasmLimits Result;
+  Result.Flags = readVaruint32(Ctx);
+  Result.Minimum = readVaruint64(Ctx);
+  if (Result.Flags & wasm::WASM_LIMITS_FLAG_HAS_MAX)
+    Result.Maximum = readVaruint64(Ctx);
+  return Result;
+}
+
+static wasm::WasmTableType readTableType(WasmObjectFile::ReadContext &Ctx) {
+  wasm::WasmTableType TableType;
+  TableType.ElemType = readUint8(Ctx);
+  TableType.Limits = readLimits(Ctx);
+  return TableType;
+}
+
+static Error readSection(WasmSection &Section, WasmObjectFile::ReadContext &Ctx,
+                         WasmSectionOrderChecker &Checker) {
+  Section.Offset = Ctx.Ptr - Ctx.Start;
+  Section.Type = readUint8(Ctx);
+  LLVM_DEBUG(dbgs() << "readSection type=" << Section.Type << "\n");
+  uint32_t Size = readVaruint32(Ctx);
+  if (Size == 0)
+    return make_error<StringError>("zero length section",
+                                   object_error::parse_failed);
+  if (Ctx.Ptr + Size > Ctx.End)
+    return make_error<StringError>("section too large",
+                                   object_error::parse_failed);
+  if (Section.Type == wasm::WASM_SEC_CUSTOM) {
+    WasmObjectFile::ReadContext SectionCtx;
+    SectionCtx.Start = Ctx.Ptr;
+    SectionCtx.Ptr = Ctx.Ptr;
+    SectionCtx.End = Ctx.Ptr + Size;
+
+    Section.Name = readString(SectionCtx);
+
+    uint32_t SectionNameSize = SectionCtx.Ptr - SectionCtx.Start;
+    Ctx.Ptr += SectionNameSize;
+    Size -= SectionNameSize;
+  }
+
+  if (!Checker.isValidSectionOrder(Section.Type, Section.Name)) {
+    return make_error<StringError>("out of order section type: " +
+                                       llvm::to_string(Section.Type),
+                                   object_error::parse_failed);
+  }
+
+  Section.Content = ArrayRef<uint8_t>(Ctx.Ptr, Size);
+  Ctx.Ptr += Size;
+  return Error::success();
+}
+
+WasmObjectFile::WasmObjectFile(MemoryBufferRef Buffer, Error &Err)
+    : ObjectFile(Binary::ID_Wasm, Buffer) {
+  ErrorAsOutParameter ErrAsOutParam(&Err);
+  Header.Magic = getData().substr(0, 4);
+  if (Header.Magic != StringRef("\0asm", 4)) {
+    Err = make_error<StringError>("invalid magic number",
+                                  object_error::parse_failed);
+    return;
+  }
+
+  ReadContext Ctx;
+  Ctx.Start = getData().bytes_begin();
+  Ctx.Ptr = Ctx.Start + 4;
+  Ctx.End = Ctx.Start + getData().size();
+
+  if (Ctx.Ptr + 4 > Ctx.End) {
+    Err = make_error<StringError>("missing version number",
+                                  object_error::parse_failed);
+    return;
+  }
+
+  Header.Version = readUint32(Ctx);
+  if (Header.Version != wasm::WasmVersion) {
+    Err = make_error<StringError>("invalid version number: " +
+                                      Twine(Header.Version),
+                                  object_error::parse_failed);
+    return;
+  }
+
+  WasmSectionOrderChecker Checker;
+  while (Ctx.Ptr < Ctx.End) {
+    WasmSection Sec;
+    if ((Err = readSection(Sec, Ctx, Checker)))
+      return;
+    if ((Err = parseSection(Sec)))
+      return;
+
+    Sections.push_back(Sec);
+  }
+}
+
+Error WasmObjectFile::parseSection(WasmSection &Sec) {
+  ReadContext Ctx;
+  Ctx.Start = Sec.Content.data();
+  Ctx.End = Ctx.Start + Sec.Content.size();
+  Ctx.Ptr = Ctx.Start;
+  switch (Sec.Type) {
+  case wasm::WASM_SEC_CUSTOM:
+    return parseCustomSection(Sec, Ctx);
+  case wasm::WASM_SEC_TYPE:
+    return parseTypeSection(Ctx);
+  case wasm::WASM_SEC_IMPORT:
+    return parseImportSection(Ctx);
+  case wasm::WASM_SEC_FUNCTION:
+    return parseFunctionSection(Ctx);
+  case wasm::WASM_SEC_TABLE:
+    return parseTableSection(Ctx);
+  case wasm::WASM_SEC_MEMORY:
+    return parseMemorySection(Ctx);
+  case wasm::WASM_SEC_TAG:
+    return parseTagSection(Ctx);
+  case wasm::WASM_SEC_GLOBAL:
+    return parseGlobalSection(Ctx);
+  case wasm::WASM_SEC_EXPORT:
+    return parseExportSection(Ctx);
+  case wasm::WASM_SEC_START:
+    return parseStartSection(Ctx);
+  case wasm::WASM_SEC_ELEM:
+    return parseElemSection(Ctx);
+  case wasm::WASM_SEC_CODE:
+    return parseCodeSection(Ctx);
+  case wasm::WASM_SEC_DATA:
+    return parseDataSection(Ctx);
+  case wasm::WASM_SEC_DATACOUNT:
+    return parseDataCountSection(Ctx);
+  default:
+    return make_error<GenericBinaryError>(
+        "invalid section type: " + Twine(Sec.Type), object_error::parse_failed);
+  }
+}
+
+Error WasmObjectFile::parseDylinkSection(ReadContext &Ctx) {
+  // Legacy "dylink" section support.
+  // See parseDylink0Section for the current "dylink.0" section parsing.
+  HasDylinkSection = true;
+  DylinkInfo.MemorySize = readVaruint32(Ctx);
+  DylinkInfo.MemoryAlignment = readVaruint32(Ctx);
+  DylinkInfo.TableSize = readVaruint32(Ctx);
+  DylinkInfo.TableAlignment = readVaruint32(Ctx);
+  uint32_t Count = readVaruint32(Ctx);
+  while (Count--) {
+    DylinkInfo.Needed.push_back(readString(Ctx));
+  }
+
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("dylink section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseDylink0Section(ReadContext &Ctx) {
+  // See
+  // https://github.com/WebAssembly/tool-conventions/blob/main/DynamicLinking.md
+  HasDylinkSection = true;
+
+  const uint8_t *OrigEnd = Ctx.End;
+  while (Ctx.Ptr < OrigEnd) {
+    Ctx.End = OrigEnd;
+    uint8_t Type = readUint8(Ctx);
+    uint32_t Size = readVaruint32(Ctx);
+    LLVM_DEBUG(dbgs() << "readSubsection type=" << int(Type) << " size=" << Size
+                      << "\n");
+    Ctx.End = Ctx.Ptr + Size;
+    uint32_t Count;
+    switch (Type) {
+    case wasm::WASM_DYLINK_MEM_INFO:
+      DylinkInfo.MemorySize = readVaruint32(Ctx);
+      DylinkInfo.MemoryAlignment = readVaruint32(Ctx);
+      DylinkInfo.TableSize = readVaruint32(Ctx);
+      DylinkInfo.TableAlignment = readVaruint32(Ctx);
+      break;
+    case wasm::WASM_DYLINK_NEEDED:
+      Count = readVaruint32(Ctx);
+      while (Count--) {
+        DylinkInfo.Needed.push_back(readString(Ctx));
+      }
+      break;
+    case wasm::WASM_DYLINK_EXPORT_INFO: {
+      uint32_t Count = readVaruint32(Ctx);
+      while (Count--) {
+        DylinkInfo.ExportInfo.push_back({readString(Ctx), readVaruint32(Ctx)});
+      }
+      break;
+    }
+    case wasm::WASM_DYLINK_IMPORT_INFO: {
+      uint32_t Count = readVaruint32(Ctx);
+      while (Count--) {
+        DylinkInfo.ImportInfo.push_back(
+            {readString(Ctx), readString(Ctx), readVaruint32(Ctx)});
+      }
+      break;
+    }
+    default:
+      LLVM_DEBUG(dbgs() << "unknown dylink.0 sub-section: " << Type << "\n");
+      Ctx.Ptr += Size;
+      break;
+    }
+    if (Ctx.Ptr != Ctx.End) {
+      return make_error<GenericBinaryError>(
+          "dylink.0 sub-section ended prematurely", object_error::parse_failed);
+    }
+  }
+
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("dylink.0 section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseNameSection(ReadContext &Ctx) {
+  llvm::DenseSet<uint64_t> SeenFunctions;
+  llvm::DenseSet<uint64_t> SeenGlobals;
+  llvm::DenseSet<uint64_t> SeenSegments;
+
+  while (Ctx.Ptr < Ctx.End) {
+    uint8_t Type = readUint8(Ctx);
+    uint32_t Size = readVaruint32(Ctx);
+    const uint8_t *SubSectionEnd = Ctx.Ptr + Size;
+    switch (Type) {
+    case wasm::WASM_NAMES_FUNCTION:
+    case wasm::WASM_NAMES_GLOBAL:
+    case wasm::WASM_NAMES_DATA_SEGMENT: {
+      uint32_t Count = readVaruint32(Ctx);
+      while (Count--) {
+        uint32_t Index = readVaruint32(Ctx);
+        StringRef Name = readString(Ctx);
+        wasm::NameType nameType = wasm::NameType::FUNCTION;
+        if (Type == wasm::WASM_NAMES_FUNCTION) {
+          if (!SeenFunctions.insert(Index).second)
+            return make_error<GenericBinaryError>(
+                "function named more than once", object_error::parse_failed);
+          if (!isValidFunctionIndex(Index) || Name.empty())
+            return make_error<GenericBinaryError>("invalid function name entry",
+                                                  object_error::parse_failed);
+
+          if (isDefinedFunctionIndex(Index))
+            getDefinedFunction(Index).DebugName = Name;
+        } else if (Type == wasm::WASM_NAMES_GLOBAL) {
+          nameType = wasm::NameType::GLOBAL;
+          if (!SeenGlobals.insert(Index).second)
+            return make_error<GenericBinaryError>("global named more than once",
+                                                  object_error::parse_failed);
+          if (!isValidGlobalIndex(Index) || Name.empty())
+            return make_error<GenericBinaryError>("invalid global name entry",
+                                                  object_error::parse_failed);
+        } else {
+          nameType = wasm::NameType::DATA_SEGMENT;
+          if (!SeenSegments.insert(Index).second)
+            return make_error<GenericBinaryError>(
+                "segment named more than once", object_error::parse_failed);
+          if (Index > DataSegments.size())
+            return make_error<GenericBinaryError>("invalid data segment name entry",
+                                                  object_error::parse_failed);
+        }
+        DebugNames.push_back(wasm::WasmDebugName{nameType, Index, Name});
+      }
+      break;
+    }
+    // Ignore local names for now
+    case wasm::WASM_NAMES_LOCAL:
+    default:
+      Ctx.Ptr += Size;
+      break;
+    }
+    if (Ctx.Ptr != SubSectionEnd)
+      return make_error<GenericBinaryError>(
+          "name sub-section ended prematurely", object_error::parse_failed);
+  }
+
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("name section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseLinkingSection(ReadContext &Ctx) {
+  HasLinkingSection = true;
+
+  LinkingData.Version = readVaruint32(Ctx);
+  if (LinkingData.Version != wasm::WasmMetadataVersion) {
+    return make_error<GenericBinaryError>(
+        "unexpected metadata version: " + Twine(LinkingData.Version) +
+            " (Expected: " + Twine(wasm::WasmMetadataVersion) + ")",
+        object_error::parse_failed);
+  }
+
+  const uint8_t *OrigEnd = Ctx.End;
+  while (Ctx.Ptr < OrigEnd) {
+    Ctx.End = OrigEnd;
+    uint8_t Type = readUint8(Ctx);
+    uint32_t Size = readVaruint32(Ctx);
+    LLVM_DEBUG(dbgs() << "readSubsection type=" << int(Type) << " size=" << Size
+                      << "\n");
+    Ctx.End = Ctx.Ptr + Size;
+    switch (Type) {
+    case wasm::WASM_SYMBOL_TABLE:
+      if (Error Err = parseLinkingSectionSymtab(Ctx))
+        return Err;
+      break;
+    case wasm::WASM_SEGMENT_INFO: {
+      uint32_t Count = readVaruint32(Ctx);
+      if (Count > DataSegments.size())
+        return make_error<GenericBinaryError>("too many segment names",
+                                              object_error::parse_failed);
+      for (uint32_t I = 0; I < Count; I++) {
+        DataSegments[I].Data.Name = readString(Ctx);
+        DataSegments[I].Data.Alignment = readVaruint32(Ctx);
+        DataSegments[I].Data.LinkingFlags = readVaruint32(Ctx);
+      }
+      break;
+    }
+    case wasm::WASM_INIT_FUNCS: {
+      uint32_t Count = readVaruint32(Ctx);
+      LinkingData.InitFunctions.reserve(Count);
+      for (uint32_t I = 0; I < Count; I++) {
+        wasm::WasmInitFunc Init;
+        Init.Priority = readVaruint32(Ctx);
+        Init.Symbol = readVaruint32(Ctx);
+        if (!isValidFunctionSymbol(Init.Symbol))
+          return make_error<GenericBinaryError>("invalid function symbol: " +
+                                                    Twine(Init.Symbol),
+                                                object_error::parse_failed);
+        LinkingData.InitFunctions.emplace_back(Init);
+      }
+      break;
+    }
+    case wasm::WASM_COMDAT_INFO:
+      if (Error Err = parseLinkingSectionComdat(Ctx))
+        return Err;
+      break;
+    default:
+      Ctx.Ptr += Size;
+      break;
+    }
+    if (Ctx.Ptr != Ctx.End)
+      return make_error<GenericBinaryError>(
+          "linking sub-section ended prematurely", object_error::parse_failed);
+  }
+  if (Ctx.Ptr != OrigEnd)
+    return make_error<GenericBinaryError>("linking section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseLinkingSectionSymtab(ReadContext &Ctx) {
+  uint32_t Count = readVaruint32(Ctx);
+  LinkingData.SymbolTable.reserve(Count);
+  Symbols.reserve(Count);
+  StringSet<> SymbolNames;
+
+  std::vector<wasm::WasmImport *> ImportedGlobals;
+  std::vector<wasm::WasmImport *> ImportedFunctions;
+  std::vector<wasm::WasmImport *> ImportedTags;
+  std::vector<wasm::WasmImport *> ImportedTables;
+  ImportedGlobals.reserve(Imports.size());
+  ImportedFunctions.reserve(Imports.size());
+  ImportedTags.reserve(Imports.size());
+  ImportedTables.reserve(Imports.size());
+  for (auto &I : Imports) {
+    if (I.Kind == wasm::WASM_EXTERNAL_FUNCTION)
+      ImportedFunctions.emplace_back(&I);
+    else if (I.Kind == wasm::WASM_EXTERNAL_GLOBAL)
+      ImportedGlobals.emplace_back(&I);
+    else if (I.Kind == wasm::WASM_EXTERNAL_TAG)
+      ImportedTags.emplace_back(&I);
+    else if (I.Kind == wasm::WASM_EXTERNAL_TABLE)
+      ImportedTables.emplace_back(&I);
+  }
+
+  while (Count--) {
+    wasm::WasmSymbolInfo Info;
+    const wasm::WasmSignature *Signature = nullptr;
+    const wasm::WasmGlobalType *GlobalType = nullptr;
+    const wasm::WasmTableType *TableType = nullptr;
+
+    Info.Kind = readUint8(Ctx);
+    Info.Flags = readVaruint32(Ctx);
+    bool IsDefined = (Info.Flags & wasm::WASM_SYMBOL_UNDEFINED) == 0;
+
+    switch (Info.Kind) {
+    case wasm::WASM_SYMBOL_TYPE_FUNCTION:
+      Info.ElementIndex = readVaruint32(Ctx);
+      if (!isValidFunctionIndex(Info.ElementIndex) ||
+          IsDefined != isDefinedFunctionIndex(Info.ElementIndex))
+        return make_error<GenericBinaryError>("invalid function symbol index",
+                                              object_error::parse_failed);
+      if (IsDefined) {
+        Info.Name = readString(Ctx);
+        unsigned FuncIndex = Info.ElementIndex - NumImportedFunctions;
+        wasm::WasmFunction &Function = Functions[FuncIndex];
+        Signature = &Signatures[Function.SigIndex];
+        if (Function.SymbolName.empty())
+          Function.SymbolName = Info.Name;
+      } else {
+        wasm::WasmImport &Import = *ImportedFunctions[Info.ElementIndex];
+        if ((Info.Flags & wasm::WASM_SYMBOL_EXPLICIT_NAME) != 0) {
+          Info.Name = readString(Ctx);
+          Info.ImportName = Import.Field;
+        } else {
+          Info.Name = Import.Field;
+        }
+        Signature = &Signatures[Import.SigIndex];
+        Info.ImportModule = Import.Module;
+      }
+      break;
+
+    case wasm::WASM_SYMBOL_TYPE_GLOBAL:
+      Info.ElementIndex = readVaruint32(Ctx);
+      if (!isValidGlobalIndex(Info.ElementIndex) ||
+          IsDefined != isDefinedGlobalIndex(Info.ElementIndex))
+        return make_error<GenericBinaryError>("invalid global symbol index",
+                                              object_error::parse_failed);
+      if (!IsDefined && (Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) ==
+                            wasm::WASM_SYMBOL_BINDING_WEAK)
+        return make_error<GenericBinaryError>("undefined weak global symbol",
+                                              object_error::parse_failed);
+      if (IsDefined) {
+        Info.Name = readString(Ctx);
+        unsigned GlobalIndex = Info.ElementIndex - NumImportedGlobals;
+        wasm::WasmGlobal &Global = Globals[GlobalIndex];
+        GlobalType = &Global.Type;
+        if (Global.SymbolName.empty())
+          Global.SymbolName = Info.Name;
+      } else {
+        wasm::WasmImport &Import = *ImportedGlobals[Info.ElementIndex];
+        if ((Info.Flags & wasm::WASM_SYMBOL_EXPLICIT_NAME) != 0) {
+          Info.Name = readString(Ctx);
+          Info.ImportName = Import.Field;
+        } else {
+          Info.Name = Import.Field;
+        }
+        GlobalType = &Import.Global;
+        Info.ImportModule = Import.Module;
+      }
+      break;
+
+    case wasm::WASM_SYMBOL_TYPE_TABLE:
+      Info.ElementIndex = readVaruint32(Ctx);
+      if (!isValidTableNumber(Info.ElementIndex) ||
+          IsDefined != isDefinedTableNumber(Info.ElementIndex))
+        return make_error<GenericBinaryError>("invalid table symbol index",
+                                              object_error::parse_failed);
+      if (!IsDefined && (Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) ==
+                            wasm::WASM_SYMBOL_BINDING_WEAK)
+        return make_error<GenericBinaryError>("undefined weak table symbol",
+                                              object_error::parse_failed);
+      if (IsDefined) {
+        Info.Name = readString(Ctx);
+        unsigned TableNumber = Info.ElementIndex - NumImportedTables;
+        wasm::WasmTable &Table = Tables[TableNumber];
+        TableType = &Table.Type;
+        if (Table.SymbolName.empty())
+          Table.SymbolName = Info.Name;
+      } else {
+        wasm::WasmImport &Import = *ImportedTables[Info.ElementIndex];
+        if ((Info.Flags & wasm::WASM_SYMBOL_EXPLICIT_NAME) != 0) {
+          Info.Name = readString(Ctx);
+          Info.ImportName = Import.Field;
+        } else {
+          Info.Name = Import.Field;
+        }
+        TableType = &Import.Table;
+        Info.ImportModule = Import.Module;
+      }
+      break;
+
+    case wasm::WASM_SYMBOL_TYPE_DATA:
+      Info.Name = readString(Ctx);
+      if (IsDefined) {
+        auto Index = readVaruint32(Ctx);
+        if (Index >= DataSegments.size())
+          return make_error<GenericBinaryError>("invalid data symbol index",
+                                                object_error::parse_failed);
+        auto Offset = readVaruint64(Ctx);
+        auto Size = readVaruint64(Ctx);
+        size_t SegmentSize = DataSegments[Index].Data.Content.size();
+        if (Offset > SegmentSize)
+          return make_error<GenericBinaryError>(
+              "invalid data symbol offset: `" + Info.Name + "` (offset: " +
+                  Twine(Offset) + " segment size: " + Twine(SegmentSize) + ")",
+              object_error::parse_failed);
+        Info.DataRef = wasm::WasmDataReference{Index, Offset, Size};
+      }
+      break;
+
+    case wasm::WASM_SYMBOL_TYPE_SECTION: {
+      if ((Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) !=
+          wasm::WASM_SYMBOL_BINDING_LOCAL)
+        return make_error<GenericBinaryError>(
+            "section symbols must have local binding",
+            object_error::parse_failed);
+      Info.ElementIndex = readVaruint32(Ctx);
+      // Use somewhat unique section name as symbol name.
+      StringRef SectionName = Sections[Info.ElementIndex].Name;
+      Info.Name = SectionName;
+      break;
+    }
+
+    case wasm::WASM_SYMBOL_TYPE_TAG: {
+      Info.ElementIndex = readVaruint32(Ctx);
+      if (!isValidTagIndex(Info.ElementIndex) ||
+          IsDefined != isDefinedTagIndex(Info.ElementIndex))
+        return make_error<GenericBinaryError>("invalid tag symbol index",
+                                              object_error::parse_failed);
+      if (!IsDefined && (Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) ==
+                            wasm::WASM_SYMBOL_BINDING_WEAK)
+        return make_error<GenericBinaryError>("undefined weak global symbol",
+                                              object_error::parse_failed);
+      if (IsDefined) {
+        Info.Name = readString(Ctx);
+        unsigned TagIndex = Info.ElementIndex - NumImportedTags;
+        wasm::WasmTag &Tag = Tags[TagIndex];
+        Signature = &Signatures[Tag.SigIndex];
+        if (Tag.SymbolName.empty())
+          Tag.SymbolName = Info.Name;
+
+      } else {
+        wasm::WasmImport &Import = *ImportedTags[Info.ElementIndex];
+        if ((Info.Flags & wasm::WASM_SYMBOL_EXPLICIT_NAME) != 0) {
+          Info.Name = readString(Ctx);
+          Info.ImportName = Import.Field;
+        } else {
+          Info.Name = Import.Field;
+        }
+        Signature = &Signatures[Import.SigIndex];
+        Info.ImportModule = Import.Module;
+      }
+      break;
+    }
+
+    default:
+      return make_error<GenericBinaryError>("invalid symbol type: " +
+                                                Twine(unsigned(Info.Kind)),
+                                            object_error::parse_failed);
+    }
+
+    if ((Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) !=
+            wasm::WASM_SYMBOL_BINDING_LOCAL &&
+        !SymbolNames.insert(Info.Name).second)
+      return make_error<GenericBinaryError>("duplicate symbol name " +
+                                                Twine(Info.Name),
+                                            object_error::parse_failed);
+    LinkingData.SymbolTable.emplace_back(Info);
+    Symbols.emplace_back(LinkingData.SymbolTable.back(), GlobalType, TableType,
+                         Signature);
+    LLVM_DEBUG(dbgs() << "Adding symbol: " << Symbols.back() << "\n");
+  }
+
+  return Error::success();
+}
+
+Error WasmObjectFile::parseLinkingSectionComdat(ReadContext &Ctx) {
+  uint32_t ComdatCount = readVaruint32(Ctx);
+  StringSet<> ComdatSet;
+  for (unsigned ComdatIndex = 0; ComdatIndex < ComdatCount; ++ComdatIndex) {
+    StringRef Name = readString(Ctx);
+    if (Name.empty() || !ComdatSet.insert(Name).second)
+      return make_error<GenericBinaryError>("bad/duplicate COMDAT name " +
+                                                Twine(Name),
+                                            object_error::parse_failed);
+    LinkingData.Comdats.emplace_back(Name);
+    uint32_t Flags = readVaruint32(Ctx);
+    if (Flags != 0)
+      return make_error<GenericBinaryError>("unsupported COMDAT flags",
+                                            object_error::parse_failed);
+
+    uint32_t EntryCount = readVaruint32(Ctx);
+    while (EntryCount--) {
+      unsigned Kind = readVaruint32(Ctx);
+      unsigned Index = readVaruint32(Ctx);
+      switch (Kind) {
+      default:
+        return make_error<GenericBinaryError>("invalid COMDAT entry type",
+                                              object_error::parse_failed);
+      case wasm::WASM_COMDAT_DATA:
+        if (Index >= DataSegments.size())
+          return make_error<GenericBinaryError>(
+              "COMDAT data index out of range", object_error::parse_failed);
+        if (DataSegments[Index].Data.Comdat != UINT32_MAX)
+          return make_error<GenericBinaryError>("data segment in two COMDATs",
+                                                object_error::parse_failed);
+        DataSegments[Index].Data.Comdat = ComdatIndex;
+        break;
+      case wasm::WASM_COMDAT_FUNCTION:
+        if (!isDefinedFunctionIndex(Index))
+          return make_error<GenericBinaryError>(
+              "COMDAT function index out of range", object_error::parse_failed);
+        if (getDefinedFunction(Index).Comdat != UINT32_MAX)
+          return make_error<GenericBinaryError>("function in two COMDATs",
+                                                object_error::parse_failed);
+        getDefinedFunction(Index).Comdat = ComdatIndex;
+        break;
+      case wasm::WASM_COMDAT_SECTION:
+        if (Index >= Sections.size())
+          return make_error<GenericBinaryError>(
+              "COMDAT section index out of range", object_error::parse_failed);
+        if (Sections[Index].Type != wasm::WASM_SEC_CUSTOM)
+          return make_error<GenericBinaryError>(
+              "non-custom section in a COMDAT", object_error::parse_failed);
+        Sections[Index].Comdat = ComdatIndex;
+        break;
+      }
+    }
+  }
+  return Error::success();
+}
+
+Error WasmObjectFile::parseProducersSection(ReadContext &Ctx) {
+  llvm::SmallSet<StringRef, 3> FieldsSeen;
+  uint32_t Fields = readVaruint32(Ctx);
+  for (size_t I = 0; I < Fields; ++I) {
+    StringRef FieldName = readString(Ctx);
+    if (!FieldsSeen.insert(FieldName).second)
+      return make_error<GenericBinaryError>(
+          "producers section does not have unique fields",
+          object_error::parse_failed);
+    std::vector<std::pair<std::string, std::string>> *ProducerVec = nullptr;
+    if (FieldName == "language") {
+      ProducerVec = &ProducerInfo.Languages;
+    } else if (FieldName == "processed-by") {
+      ProducerVec = &ProducerInfo.Tools;
+    } else if (FieldName == "sdk") {
+      ProducerVec = &ProducerInfo.SDKs;
+    } else {
+      return make_error<GenericBinaryError>(
+          "producers section field is not named one of language, processed-by, "
+          "or sdk",
+          object_error::parse_failed);
+    }
+    uint32_t ValueCount = readVaruint32(Ctx);
+    llvm::SmallSet<StringRef, 8> ProducersSeen;
+    for (size_t J = 0; J < ValueCount; ++J) {
+      StringRef Name = readString(Ctx);
+      StringRef Version = readString(Ctx);
+      if (!ProducersSeen.insert(Name).second) {
+        return make_error<GenericBinaryError>(
+            "producers section contains repeated producer",
+            object_error::parse_failed);
+      }
+      ProducerVec->emplace_back(std::string(Name), std::string(Version));
+    }
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("producers section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseTargetFeaturesSection(ReadContext &Ctx) {
+  llvm::SmallSet<std::string, 8> FeaturesSeen;
+  uint32_t FeatureCount = readVaruint32(Ctx);
+  for (size_t I = 0; I < FeatureCount; ++I) {
+    wasm::WasmFeatureEntry Feature;
+    Feature.Prefix = readUint8(Ctx);
+    switch (Feature.Prefix) {
+    case wasm::WASM_FEATURE_PREFIX_USED:
+    case wasm::WASM_FEATURE_PREFIX_REQUIRED:
+    case wasm::WASM_FEATURE_PREFIX_DISALLOWED:
+      break;
+    default:
+      return make_error<GenericBinaryError>("unknown feature policy prefix",
+                                            object_error::parse_failed);
+    }
+    Feature.Name = std::string(readString(Ctx));
+    if (!FeaturesSeen.insert(Feature.Name).second)
+      return make_error<GenericBinaryError>(
+          "target features section contains repeated feature \"" +
+              Feature.Name + "\"",
+          object_error::parse_failed);
+    TargetFeatures.push_back(Feature);
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>(
+        "target features section ended prematurely",
+        object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseRelocSection(StringRef Name, ReadContext &Ctx) {
+  uint32_t SectionIndex = readVaruint32(Ctx);
+  if (SectionIndex >= Sections.size())
+    return make_error<GenericBinaryError>("invalid section index",
+                                          object_error::parse_failed);
+  WasmSection &Section = Sections[SectionIndex];
+  uint32_t RelocCount = readVaruint32(Ctx);
+  uint32_t EndOffset = Section.Content.size();
+  uint32_t PreviousOffset = 0;
+  while (RelocCount--) {
+    wasm::WasmRelocation Reloc = {};
+    uint32_t type = readVaruint32(Ctx);
+    Reloc.Type = type;
+    Reloc.Offset = readVaruint32(Ctx);
+    if (Reloc.Offset < PreviousOffset)
+      return make_error<GenericBinaryError>("relocations not in offset order",
+                                            object_error::parse_failed);
+    PreviousOffset = Reloc.Offset;
+    Reloc.Index = readVaruint32(Ctx);
+    switch (type) {
+    case wasm::R_WASM_FUNCTION_INDEX_LEB:
+    case wasm::R_WASM_TABLE_INDEX_SLEB:
+    case wasm::R_WASM_TABLE_INDEX_SLEB64:
+    case wasm::R_WASM_TABLE_INDEX_I32:
+    case wasm::R_WASM_TABLE_INDEX_I64:
+    case wasm::R_WASM_TABLE_INDEX_REL_SLEB:
+    case wasm::R_WASM_TABLE_INDEX_REL_SLEB64:
+      if (!isValidFunctionSymbol(Reloc.Index))
+        return make_error<GenericBinaryError>(
+            "invalid relocation function index", object_error::parse_failed);
+      break;
+    case wasm::R_WASM_TABLE_NUMBER_LEB:
+      if (!isValidTableSymbol(Reloc.Index))
+        return make_error<GenericBinaryError>("invalid relocation table index",
+                                              object_error::parse_failed);
+      break;
+    case wasm::R_WASM_TYPE_INDEX_LEB:
+      if (Reloc.Index >= Signatures.size())
+        return make_error<GenericBinaryError>("invalid relocation type index",
+                                              object_error::parse_failed);
+      break;
+    case wasm::R_WASM_GLOBAL_INDEX_LEB:
+      // R_WASM_GLOBAL_INDEX_LEB are can be used against function and data
+      // symbols to refer to their GOT entries.
+      if (!isValidGlobalSymbol(Reloc.Index) &&
+          !isValidDataSymbol(Reloc.Index) &&
+          !isValidFunctionSymbol(Reloc.Index))
+        return make_error<GenericBinaryError>("invalid relocation global index",
+                                              object_error::parse_failed);
+      break;
+    case wasm::R_WASM_GLOBAL_INDEX_I32:
+      if (!isValidGlobalSymbol(Reloc.Index))
+        return make_error<GenericBinaryError>("invalid relocation global index",
+                                              object_error::parse_failed);
+      break;
+    case wasm::R_WASM_TAG_INDEX_LEB:
+      if (!isValidTagSymbol(Reloc.Index))
+        return make_error<GenericBinaryError>("invalid relocation tag index",
+                                              object_error::parse_failed);
+      break;
+    case wasm::R_WASM_MEMORY_ADDR_LEB:
+    case wasm::R_WASM_MEMORY_ADDR_SLEB:
+    case wasm::R_WASM_MEMORY_ADDR_I32:
+    case wasm::R_WASM_MEMORY_ADDR_REL_SLEB:
+    case wasm::R_WASM_MEMORY_ADDR_TLS_SLEB:
+    case wasm::R_WASM_MEMORY_ADDR_LOCREL_I32:
+      if (!isValidDataSymbol(Reloc.Index))
+        return make_error<GenericBinaryError>("invalid relocation data index",
+                                              object_error::parse_failed);
+      Reloc.Addend = readVarint32(Ctx);
+      break;
+    case wasm::R_WASM_MEMORY_ADDR_LEB64:
+    case wasm::R_WASM_MEMORY_ADDR_SLEB64:
+    case wasm::R_WASM_MEMORY_ADDR_I64:
+    case wasm::R_WASM_MEMORY_ADDR_REL_SLEB64:
+    case wasm::R_WASM_MEMORY_ADDR_TLS_SLEB64:
+      if (!isValidDataSymbol(Reloc.Index))
+        return make_error<GenericBinaryError>("invalid relocation data index",
+                                              object_error::parse_failed);
+      Reloc.Addend = readVarint64(Ctx);
+      break;
+    case wasm::R_WASM_FUNCTION_OFFSET_I32:
+      if (!isValidFunctionSymbol(Reloc.Index))
+        return make_error<GenericBinaryError>(
+            "invalid relocation function index", object_error::parse_failed);
+      Reloc.Addend = readVarint32(Ctx);
+      break;
+    case wasm::R_WASM_FUNCTION_OFFSET_I64:
+      if (!isValidFunctionSymbol(Reloc.Index))
+        return make_error<GenericBinaryError>(
+            "invalid relocation function index", object_error::parse_failed);
+      Reloc.Addend = readVarint64(Ctx);
+      break;
+    case wasm::R_WASM_SECTION_OFFSET_I32:
+      if (!isValidSectionSymbol(Reloc.Index))
+        return make_error<GenericBinaryError>(
+            "invalid relocation section index", object_error::parse_failed);
+      Reloc.Addend = readVarint32(Ctx);
+      break;
+    default:
+      return make_error<GenericBinaryError>("invalid relocation type: " +
+                                                Twine(type),
+                                            object_error::parse_failed);
+    }
+
+    // Relocations must fit inside the section, and must appear in order.  They
+    // also shouldn't overlap a function/element boundary, but we don't bother
+    // to check that.
+    uint64_t Size = 5;
+    if (Reloc.Type == wasm::R_WASM_MEMORY_ADDR_LEB64 ||
+        Reloc.Type == wasm::R_WASM_MEMORY_ADDR_SLEB64 ||
+        Reloc.Type == wasm::R_WASM_MEMORY_ADDR_REL_SLEB64)
+      Size = 10;
+    if (Reloc.Type == wasm::R_WASM_TABLE_INDEX_I32 ||
+        Reloc.Type == wasm::R_WASM_MEMORY_ADDR_I32 ||
+        Reloc.Type == wasm::R_WASM_MEMORY_ADDR_LOCREL_I32 ||
+        Reloc.Type == wasm::R_WASM_SECTION_OFFSET_I32 ||
+        Reloc.Type == wasm::R_WASM_FUNCTION_OFFSET_I32 ||
+        Reloc.Type == wasm::R_WASM_GLOBAL_INDEX_I32)
+      Size = 4;
+    if (Reloc.Type == wasm::R_WASM_TABLE_INDEX_I64 ||
+        Reloc.Type == wasm::R_WASM_MEMORY_ADDR_I64 ||
+        Reloc.Type == wasm::R_WASM_FUNCTION_OFFSET_I64)
+      Size = 8;
+    if (Reloc.Offset + Size > EndOffset)
+      return make_error<GenericBinaryError>("invalid relocation offset",
+                                            object_error::parse_failed);
+
+    Section.Relocations.push_back(Reloc);
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("reloc section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseCustomSection(WasmSection &Sec, ReadContext &Ctx) {
+  if (Sec.Name == "dylink") {
+    if (Error Err = parseDylinkSection(Ctx))
+      return Err;
+  } else if (Sec.Name == "dylink.0") {
+    if (Error Err = parseDylink0Section(Ctx))
+      return Err;
+  } else if (Sec.Name == "name") {
+    if (Error Err = parseNameSection(Ctx))
+      return Err;
+  } else if (Sec.Name == "linking") {
+    if (Error Err = parseLinkingSection(Ctx))
+      return Err;
+  } else if (Sec.Name == "producers") {
+    if (Error Err = parseProducersSection(Ctx))
+      return Err;
+  } else if (Sec.Name == "target_features") {
+    if (Error Err = parseTargetFeaturesSection(Ctx))
+      return Err;
+  } else if (Sec.Name.startswith("reloc.")) {
+    if (Error Err = parseRelocSection(Sec.Name, Ctx))
+      return Err;
+  }
+  return Error::success();
+}
+
+Error WasmObjectFile::parseTypeSection(ReadContext &Ctx) {
+  uint32_t Count = readVaruint32(Ctx);
+  Signatures.reserve(Count);
+  while (Count--) {
+    wasm::WasmSignature Sig;
+    uint8_t Form = readUint8(Ctx);
+    if (Form != wasm::WASM_TYPE_FUNC) {
+      return make_error<GenericBinaryError>("invalid signature type",
+                                            object_error::parse_failed);
+    }
+    uint32_t ParamCount = readVaruint32(Ctx);
+    Sig.Params.reserve(ParamCount);
+    while (ParamCount--) {
+      uint32_t ParamType = readUint8(Ctx);
+      Sig.Params.push_back(wasm::ValType(ParamType));
+    }
+    uint32_t ReturnCount = readVaruint32(Ctx);
+    while (ReturnCount--) {
+      uint32_t ReturnType = readUint8(Ctx);
+      Sig.Returns.push_back(wasm::ValType(ReturnType));
+    }
+    Signatures.push_back(std::move(Sig));
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("type section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseImportSection(ReadContext &Ctx) {
+  uint32_t Count = readVaruint32(Ctx);
+  uint32_t NumTypes = Signatures.size();
+  Imports.reserve(Count);
+  for (uint32_t I = 0; I < Count; I++) {
+    wasm::WasmImport Im;
+    Im.Module = readString(Ctx);
+    Im.Field = readString(Ctx);
+    Im.Kind = readUint8(Ctx);
+    switch (Im.Kind) {
+    case wasm::WASM_EXTERNAL_FUNCTION:
+      NumImportedFunctions++;
+      Im.SigIndex = readVaruint32(Ctx);
+      if (Im.SigIndex >= NumTypes)
+        return make_error<GenericBinaryError>("invalid function type",
+                                              object_error::parse_failed);
+      break;
+    case wasm::WASM_EXTERNAL_GLOBAL:
+      NumImportedGlobals++;
+      Im.Global.Type = readUint8(Ctx);
+      Im.Global.Mutable = readVaruint1(Ctx);
+      break;
+    case wasm::WASM_EXTERNAL_MEMORY:
+      Im.Memory = readLimits(Ctx);
+      if (Im.Memory.Flags & wasm::WASM_LIMITS_FLAG_IS_64)
+        HasMemory64 = true;
+      break;
+    case wasm::WASM_EXTERNAL_TABLE: {
+      Im.Table = readTableType(Ctx);
+      NumImportedTables++;
+      auto ElemType = Im.Table.ElemType;
+      if (ElemType != wasm::WASM_TYPE_FUNCREF &&
+          ElemType != wasm::WASM_TYPE_EXTERNREF)
+        return make_error<GenericBinaryError>("invalid table element type",
+                                              object_error::parse_failed);
+      break;
+    }
+    case wasm::WASM_EXTERNAL_TAG:
+      NumImportedTags++;
+      if (readUint8(Ctx) != 0) // Reserved 'attribute' field
+        return make_error<GenericBinaryError>("invalid attribute",
+                                              object_error::parse_failed);
+      Im.SigIndex = readVaruint32(Ctx);
+      if (Im.SigIndex >= NumTypes)
+        return make_error<GenericBinaryError>("invalid tag type",
+                                              object_error::parse_failed);
+      break;
+    default:
+      return make_error<GenericBinaryError>("unexpected import kind",
+                                            object_error::parse_failed);
+    }
+    Imports.push_back(Im);
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("import section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseFunctionSection(ReadContext &Ctx) {
+  uint32_t Count = readVaruint32(Ctx);
+  Functions.reserve(Count);
+  uint32_t NumTypes = Signatures.size();
+  while (Count--) {
+    uint32_t Type = readVaruint32(Ctx);
+    if (Type >= NumTypes)
+      return make_error<GenericBinaryError>("invalid function type",
+                                            object_error::parse_failed);
+    wasm::WasmFunction F;
+    F.SigIndex = Type;
+    Functions.push_back(F);
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("function section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseTableSection(ReadContext &Ctx) {
+  TableSection = Sections.size();
+  uint32_t Count = readVaruint32(Ctx);
+  Tables.reserve(Count);
+  while (Count--) {
+    wasm::WasmTable T;
+    T.Type = readTableType(Ctx);
+    T.Index = NumImportedTables + Tables.size();
+    Tables.push_back(T);
+    auto ElemType = Tables.back().Type.ElemType;
+    if (ElemType != wasm::WASM_TYPE_FUNCREF &&
+        ElemType != wasm::WASM_TYPE_EXTERNREF) {
+      return make_error<GenericBinaryError>("invalid table element type",
+                                            object_error::parse_failed);
+    }
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("table section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseMemorySection(ReadContext &Ctx) {
+  uint32_t Count = readVaruint32(Ctx);
+  Memories.reserve(Count);
+  while (Count--) {
+    auto Limits = readLimits(Ctx);
+    if (Limits.Flags & wasm::WASM_LIMITS_FLAG_IS_64)
+      HasMemory64 = true;
+    Memories.push_back(Limits);
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("memory section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseTagSection(ReadContext &Ctx) {
+  TagSection = Sections.size();
+  uint32_t Count = readVaruint32(Ctx);
+  Tags.reserve(Count);
+  uint32_t NumTypes = Signatures.size();
+  while (Count--) {
+    if (readUint8(Ctx) != 0) // Reserved 'attribute' field
+      return make_error<GenericBinaryError>("invalid attribute",
+                                            object_error::parse_failed);
+    uint32_t Type = readVaruint32(Ctx);
+    if (Type >= NumTypes)
+      return make_error<GenericBinaryError>("invalid tag type",
+                                            object_error::parse_failed);
+    wasm::WasmTag Tag;
+    Tag.Index = NumImportedTags + Tags.size();
+    Tag.SigIndex = Type;
+    Tags.push_back(Tag);
+  }
+
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("tag section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseGlobalSection(ReadContext &Ctx) {
+  GlobalSection = Sections.size();
+  uint32_t Count = readVaruint32(Ctx);
+  Globals.reserve(Count);
+  while (Count--) {
+    wasm::WasmGlobal Global;
+    Global.Index = NumImportedGlobals + Globals.size();
+    Global.Type.Type = readUint8(Ctx);
+    Global.Type.Mutable = readVaruint1(Ctx);
+    if (Error Err = readInitExpr(Global.InitExpr, Ctx))
+      return Err;
+    Globals.push_back(Global);
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("global section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseExportSection(ReadContext &Ctx) {
+  uint32_t Count = readVaruint32(Ctx);
+  Exports.reserve(Count);
+  for (uint32_t I = 0; I < Count; I++) {
+    wasm::WasmExport Ex;
+    Ex.Name = readString(Ctx);
+    Ex.Kind = readUint8(Ctx);
+    Ex.Index = readVaruint32(Ctx);
+    switch (Ex.Kind) {
+    case wasm::WASM_EXTERNAL_FUNCTION:
+
+      if (!isDefinedFunctionIndex(Ex.Index))
+        return make_error<GenericBinaryError>("invalid function export",
+                                              object_error::parse_failed);
+      getDefinedFunction(Ex.Index).ExportName = Ex.Name;
+      break;
+    case wasm::WASM_EXTERNAL_GLOBAL:
+      if (!isValidGlobalIndex(Ex.Index))
+        return make_error<GenericBinaryError>("invalid global export",
+                                              object_error::parse_failed);
+      break;
+    case wasm::WASM_EXTERNAL_TAG:
+      if (!isValidTagIndex(Ex.Index))
+        return make_error<GenericBinaryError>("invalid tag export",
+                                              object_error::parse_failed);
+      break;
+    case wasm::WASM_EXTERNAL_MEMORY:
+    case wasm::WASM_EXTERNAL_TABLE:
+      break;
+    default:
+      return make_error<GenericBinaryError>("unexpected export kind",
+                                            object_error::parse_failed);
+    }
+    Exports.push_back(Ex);
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("export section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+bool WasmObjectFile::isValidFunctionIndex(uint32_t Index) const {
+  return Index < NumImportedFunctions + Functions.size();
+}
+
+bool WasmObjectFile::isDefinedFunctionIndex(uint32_t Index) const {
+  return Index >= NumImportedFunctions && isValidFunctionIndex(Index);
+}
+
+bool WasmObjectFile::isValidGlobalIndex(uint32_t Index) const {
+  return Index < NumImportedGlobals + Globals.size();
+}
+
+bool WasmObjectFile::isValidTableNumber(uint32_t Index) const {
+  return Index < NumImportedTables + Tables.size();
+}
+
+bool WasmObjectFile::isDefinedGlobalIndex(uint32_t Index) const {
+  return Index >= NumImportedGlobals && isValidGlobalIndex(Index);
+}
+
+bool WasmObjectFile::isDefinedTableNumber(uint32_t Index) const {
+  return Index >= NumImportedTables && isValidTableNumber(Index);
+}
+
+bool WasmObjectFile::isValidTagIndex(uint32_t Index) const {
+  return Index < NumImportedTags + Tags.size();
+}
+
+bool WasmObjectFile::isDefinedTagIndex(uint32_t Index) const {
+  return Index >= NumImportedTags && isValidTagIndex(Index);
+}
+
+bool WasmObjectFile::isValidFunctionSymbol(uint32_t Index) const {
+  return Index < Symbols.size() && Symbols[Index].isTypeFunction();
+}
+
+bool WasmObjectFile::isValidTableSymbol(uint32_t Index) const {
+  return Index < Symbols.size() && Symbols[Index].isTypeTable();
+}
+
+bool WasmObjectFile::isValidGlobalSymbol(uint32_t Index) const {
+  return Index < Symbols.size() && Symbols[Index].isTypeGlobal();
+}
+
+bool WasmObjectFile::isValidTagSymbol(uint32_t Index) const {
+  return Index < Symbols.size() && Symbols[Index].isTypeTag();
+}
+
+bool WasmObjectFile::isValidDataSymbol(uint32_t Index) const {
+  return Index < Symbols.size() && Symbols[Index].isTypeData();
+}
+
+bool WasmObjectFile::isValidSectionSymbol(uint32_t Index) const {
+  return Index < Symbols.size() && Symbols[Index].isTypeSection();
+}
+
+wasm::WasmFunction &WasmObjectFile::getDefinedFunction(uint32_t Index) {
+  assert(isDefinedFunctionIndex(Index));
+  return Functions[Index - NumImportedFunctions];
+}
+
+const wasm::WasmFunction &
+WasmObjectFile::getDefinedFunction(uint32_t Index) const {
+  assert(isDefinedFunctionIndex(Index));
+  return Functions[Index - NumImportedFunctions];
+}
+
+wasm::WasmGlobal &WasmObjectFile::getDefinedGlobal(uint32_t Index) {
+  assert(isDefinedGlobalIndex(Index));
+  return Globals[Index - NumImportedGlobals];
+}
+
+wasm::WasmTag &WasmObjectFile::getDefinedTag(uint32_t Index) {
+  assert(isDefinedTagIndex(Index));
+  return Tags[Index - NumImportedTags];
+}
+
+Error WasmObjectFile::parseStartSection(ReadContext &Ctx) {
+  StartFunction = readVaruint32(Ctx);
+  if (!isValidFunctionIndex(StartFunction))
+    return make_error<GenericBinaryError>("invalid start function",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseCodeSection(ReadContext &Ctx) {
+  CodeSection = Sections.size();
+  uint32_t FunctionCount = readVaruint32(Ctx);
+  if (FunctionCount != Functions.size()) {
+    return make_error<GenericBinaryError>("invalid function count",
+                                          object_error::parse_failed);
+  }
+
+  for (uint32_t i = 0; i < FunctionCount; i++) {
+    wasm::WasmFunction& Function = Functions[i];
+    const uint8_t *FunctionStart = Ctx.Ptr;
+    uint32_t Size = readVaruint32(Ctx);
+    const uint8_t *FunctionEnd = Ctx.Ptr + Size;
+
+    Function.CodeOffset = Ctx.Ptr - FunctionStart;
+    Function.Index = NumImportedFunctions + i;
+    Function.CodeSectionOffset = FunctionStart - Ctx.Start;
+    Function.Size = FunctionEnd - FunctionStart;
+
+    uint32_t NumLocalDecls = readVaruint32(Ctx);
+    Function.Locals.reserve(NumLocalDecls);
+    while (NumLocalDecls--) {
+      wasm::WasmLocalDecl Decl;
+      Decl.Count = readVaruint32(Ctx);
+      Decl.Type = readUint8(Ctx);
+      Function.Locals.push_back(Decl);
+    }
+
+    uint32_t BodySize = FunctionEnd - Ctx.Ptr;
+    Function.Body = ArrayRef<uint8_t>(Ctx.Ptr, BodySize);
+    // This will be set later when reading in the linking metadata section.
+    Function.Comdat = UINT32_MAX;
+    Ctx.Ptr += BodySize;
+    assert(Ctx.Ptr == FunctionEnd);
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("code section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseElemSection(ReadContext &Ctx) {
+  uint32_t Count = readVaruint32(Ctx);
+  ElemSegments.reserve(Count);
+  while (Count--) {
+    wasm::WasmElemSegment Segment;
+    Segment.Flags = readVaruint32(Ctx);
+
+    uint32_t SupportedFlags = wasm::WASM_ELEM_SEGMENT_HAS_TABLE_NUMBER |
+                              wasm::WASM_ELEM_SEGMENT_IS_PASSIVE |
+                              wasm::WASM_ELEM_SEGMENT_HAS_INIT_EXPRS;
+    if (Segment.Flags & ~SupportedFlags)
+      return make_error<GenericBinaryError>(
+          "Unsupported flags for element segment", object_error::parse_failed);
+
+    if (Segment.Flags & wasm::WASM_ELEM_SEGMENT_HAS_TABLE_NUMBER)
+      Segment.TableNumber = readVaruint32(Ctx);
+    else
+      Segment.TableNumber = 0;
+    if (!isValidTableNumber(Segment.TableNumber))
+      return make_error<GenericBinaryError>("invalid TableNumber",
+                                            object_error::parse_failed);
+
+    if (Segment.Flags & wasm::WASM_ELEM_SEGMENT_IS_PASSIVE) {
+      Segment.Offset.Extended = false;
+      Segment.Offset.Inst.Opcode = wasm::WASM_OPCODE_I32_CONST;
+      Segment.Offset.Inst.Value.Int32 = 0;
+    } else {
+      if (Error Err = readInitExpr(Segment.Offset, Ctx))
+        return Err;
+    }
+
+    if (Segment.Flags & wasm::WASM_ELEM_SEGMENT_MASK_HAS_ELEM_KIND) {
+      Segment.ElemKind = readUint8(Ctx);
+      if (Segment.Flags & wasm::WASM_ELEM_SEGMENT_HAS_INIT_EXPRS) {
+        if (Segment.ElemKind != uint8_t(wasm::ValType::FUNCREF) &&
+            Segment.ElemKind != uint8_t(wasm::ValType::EXTERNREF)) {
+          return make_error<GenericBinaryError>("invalid reference type",
+                                                object_error::parse_failed);
+        }
+      } else {
+        if (Segment.ElemKind != 0)
+          return make_error<GenericBinaryError>("invalid elemtype",
+                                                object_error::parse_failed);
+        Segment.ElemKind = uint8_t(wasm::ValType::FUNCREF);
+      }
+    } else {
+      Segment.ElemKind = uint8_t(wasm::ValType::FUNCREF);
+    }
+
+    if (Segment.Flags & wasm::WASM_ELEM_SEGMENT_HAS_INIT_EXPRS)
+      return make_error<GenericBinaryError>(
+          "elem segment init expressions not yet implemented",
+          object_error::parse_failed);
+
+    uint32_t NumElems = readVaruint32(Ctx);
+    while (NumElems--) {
+      Segment.Functions.push_back(readVaruint32(Ctx));
+    }
+    ElemSegments.push_back(Segment);
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("elem section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseDataSection(ReadContext &Ctx) {
+  DataSection = Sections.size();
+  uint32_t Count = readVaruint32(Ctx);
+  if (DataCount && Count != *DataCount)
+    return make_error<GenericBinaryError>(
+        "number of data segments does not match DataCount section");
+  DataSegments.reserve(Count);
+  while (Count--) {
+    WasmSegment Segment;
+    Segment.Data.InitFlags = readVaruint32(Ctx);
+    Segment.Data.MemoryIndex =
+        (Segment.Data.InitFlags & wasm::WASM_DATA_SEGMENT_HAS_MEMINDEX)
+            ? readVaruint32(Ctx)
+            : 0;
+    if ((Segment.Data.InitFlags & wasm::WASM_DATA_SEGMENT_IS_PASSIVE) == 0) {
+      if (Error Err = readInitExpr(Segment.Data.Offset, Ctx))
+        return Err;
+    } else {
+      Segment.Data.Offset.Extended = false;
+      Segment.Data.Offset.Inst.Opcode = wasm::WASM_OPCODE_I32_CONST;
+      Segment.Data.Offset.Inst.Value.Int32 = 0;
+    }
+    uint32_t Size = readVaruint32(Ctx);
+    if (Size > (size_t)(Ctx.End - Ctx.Ptr))
+      return make_error<GenericBinaryError>("invalid segment size",
+                                            object_error::parse_failed);
+    Segment.Data.Content = ArrayRef<uint8_t>(Ctx.Ptr, Size);
+    // The rest of these Data fields are set later, when reading in the linking
+    // metadata section.
+    Segment.Data.Alignment = 0;
+    Segment.Data.LinkingFlags = 0;
+    Segment.Data.Comdat = UINT32_MAX;
+    Segment.SectionOffset = Ctx.Ptr - Ctx.Start;
+    Ctx.Ptr += Size;
+    DataSegments.push_back(Segment);
+  }
+  if (Ctx.Ptr != Ctx.End)
+    return make_error<GenericBinaryError>("data section ended prematurely",
+                                          object_error::parse_failed);
+  return Error::success();
+}
+
+Error WasmObjectFile::parseDataCountSection(ReadContext &Ctx) {
+  DataCount = readVaruint32(Ctx);
+  return Error::success();
+}
+
+const wasm::WasmObjectHeader &WasmObjectFile::getHeader() const {
+  return Header;
+}
+
+void WasmObjectFile::moveSymbolNext(DataRefImpl &Symb) const { Symb.d.b++; }
+
+Expected<uint32_t> WasmObjectFile::getSymbolFlags(DataRefImpl Symb) const {
+  uint32_t Result = SymbolRef::SF_None;
+  const WasmSymbol &Sym = getWasmSymbol(Symb);
+
+  LLVM_DEBUG(dbgs() << "getSymbolFlags: ptr=" << &Sym << " " << Sym << "\n");
+  if (Sym.isBindingWeak())
+    Result |= SymbolRef::SF_Weak;
+  if (!Sym.isBindingLocal())
+    Result |= SymbolRef::SF_Global;
+  if (Sym.isHidden())
+    Result |= SymbolRef::SF_Hidden;
+  if (!Sym.isDefined())
+    Result |= SymbolRef::SF_Undefined;
+  if (Sym.isTypeFunction())
+    Result |= SymbolRef::SF_Executable;
+  return Result;
+}
+
+basic_symbol_iterator WasmObjectFile::symbol_begin() const {
+  DataRefImpl Ref;
+  Ref.d.a = 1; // Arbitrary non-zero value so that Ref.p is non-null
+  Ref.d.b = 0; // Symbol index
+  return BasicSymbolRef(Ref, this);
+}
+
+basic_symbol_iterator WasmObjectFile::symbol_end() const {
+  DataRefImpl Ref;
+  Ref.d.a = 1; // Arbitrary non-zero value so that Ref.p is non-null
+  Ref.d.b = Symbols.size(); // Symbol index
+  return BasicSymbolRef(Ref, this);
+}
+
+const WasmSymbol &WasmObjectFile::getWasmSymbol(const DataRefImpl &Symb) const {
+  return Symbols[Symb.d.b];
+}
+
+const WasmSymbol &WasmObjectFile::getWasmSymbol(const SymbolRef &Symb) const {
+  return getWasmSymbol(Symb.getRawDataRefImpl());
+}
+
+Expected<StringRef> WasmObjectFile::getSymbolName(DataRefImpl Symb) const {
+  return getWasmSymbol(Symb).Info.Name;
+}
+
+Expected<uint64_t> WasmObjectFile::getSymbolAddress(DataRefImpl Symb) const {
+  auto &Sym = getWasmSymbol(Symb);
+  if (Sym.Info.Kind == wasm::WASM_SYMBOL_TYPE_FUNCTION &&
+      isDefinedFunctionIndex(Sym.Info.ElementIndex))
+    return getDefinedFunction(Sym.Info.ElementIndex).CodeSectionOffset;
+  else
+    return getSymbolValue(Symb);
+}
+
+uint64_t WasmObjectFile::getWasmSymbolValue(const WasmSymbol &Sym) const {
+  switch (Sym.Info.Kind) {
+  case wasm::WASM_SYMBOL_TYPE_FUNCTION:
+  case wasm::WASM_SYMBOL_TYPE_GLOBAL:
+  case wasm::WASM_SYMBOL_TYPE_TAG:
+  case wasm::WASM_SYMBOL_TYPE_TABLE:
+    return Sym.Info.ElementIndex;
+  case wasm::WASM_SYMBOL_TYPE_DATA: {
+    // The value of a data symbol is the segment offset, plus the symbol
+    // offset within the segment.
+    uint32_t SegmentIndex = Sym.Info.DataRef.Segment;
+    const wasm::WasmDataSegment &Segment = DataSegments[SegmentIndex].Data;
+    if (Segment.Offset.Extended) {
+      llvm_unreachable("extended init exprs not supported");
+    } else if (Segment.Offset.Inst.Opcode == wasm::WASM_OPCODE_I32_CONST) {
+      return Segment.Offset.Inst.Value.Int32 + Sym.Info.DataRef.Offset;
+    } else if (Segment.Offset.Inst.Opcode == wasm::WASM_OPCODE_I64_CONST) {
+      return Segment.Offset.Inst.Value.Int64 + Sym.Info.DataRef.Offset;
+    } else {
+      llvm_unreachable("unknown init expr opcode");
+    }
+  }
+  case wasm::WASM_SYMBOL_TYPE_SECTION:
+    return 0;
+  }
+  llvm_unreachable("invalid symbol type");
+}
+
+uint64_t WasmObjectFile::getSymbolValueImpl(DataRefImpl Symb) const {
+  return getWasmSymbolValue(getWasmSymbol(Symb));
+}
+
+uint32_t WasmObjectFile::getSymbolAlignment(DataRefImpl Symb) const {
+  llvm_unreachable("not yet implemented");
+  return 0;
+}
+
+uint64_t WasmObjectFile::getCommonSymbolSizeImpl(DataRefImpl Symb) const {
+  llvm_unreachable("not yet implemented");
+  return 0;
+}
+
+Expected<SymbolRef::Type>
+WasmObjectFile::getSymbolType(DataRefImpl Symb) const {
+  const WasmSymbol &Sym = getWasmSymbol(Symb);
+
+  switch (Sym.Info.Kind) {
+  case wasm::WASM_SYMBOL_TYPE_FUNCTION:
+    return SymbolRef::ST_Function;
+  case wasm::WASM_SYMBOL_TYPE_GLOBAL:
+    return SymbolRef::ST_Other;
+  case wasm::WASM_SYMBOL_TYPE_DATA:
+    return SymbolRef::ST_Data;
+  case wasm::WASM_SYMBOL_TYPE_SECTION:
+    return SymbolRef::ST_Debug;
+  case wasm::WASM_SYMBOL_TYPE_TAG:
+    return SymbolRef::ST_Other;
+  case wasm::WASM_SYMBOL_TYPE_TABLE:
+    return SymbolRef::ST_Other;
+  }
+
+  llvm_unreachable("unknown WasmSymbol::SymbolType");
+  return SymbolRef::ST_Other;
+}
+
+Expected<section_iterator>
+WasmObjectFile::getSymbolSection(DataRefImpl Symb) const {
+  const WasmSymbol &Sym = getWasmSymbol(Symb);
+  if (Sym.isUndefined())
+    return section_end();
+
+  DataRefImpl Ref;
+  Ref.d.a = getSymbolSectionIdImpl(Sym);
+  return section_iterator(SectionRef(Ref, this));
+}
+
+uint32_t WasmObjectFile::getSymbolSectionId(SymbolRef Symb) const {
+  const WasmSymbol &Sym = getWasmSymbol(Symb);
+  return getSymbolSectionIdImpl(Sym);
+}
+
+uint32_t WasmObjectFile::getSymbolSectionIdImpl(const WasmSymbol &Sym) const {
+  switch (Sym.Info.Kind) {
+  case wasm::WASM_SYMBOL_TYPE_FUNCTION:
+    return CodeSection;
+  case wasm::WASM_SYMBOL_TYPE_GLOBAL:
+    return GlobalSection;
+  case wasm::WASM_SYMBOL_TYPE_DATA:
+    return DataSection;
+  case wasm::WASM_SYMBOL_TYPE_SECTION:
+    return Sym.Info.ElementIndex;
+  case wasm::WASM_SYMBOL_TYPE_TAG:
+    return TagSection;
+  case wasm::WASM_SYMBOL_TYPE_TABLE:
+    return TableSection;
+  default:
+    llvm_unreachable("unknown WasmSymbol::SymbolType");
+  }
+}
+
+void WasmObjectFile::moveSectionNext(DataRefImpl &Sec) const { Sec.d.a++; }
+
+Expected<StringRef> WasmObjectFile::getSectionName(DataRefImpl Sec) const {
+  const WasmSection &S = Sections[Sec.d.a];
+  if (S.Type == wasm::WASM_SEC_CUSTOM)
+    return S.Name;
+  if (S.Type > wasm::WASM_SEC_LAST_KNOWN)
+    return createStringError(object_error::invalid_section_index, "");
+  return wasm::sectionTypeToString(S.Type);
+}
+
+uint64_t WasmObjectFile::getSectionAddress(DataRefImpl Sec) const { return 0; }
+
+uint64_t WasmObjectFile::getSectionIndex(DataRefImpl Sec) const {
+  return Sec.d.a;
+}
+
+uint64_t WasmObjectFile::getSectionSize(DataRefImpl Sec) const {
+  const WasmSection &S = Sections[Sec.d.a];
+  return S.Content.size();
+}
+
+Expected<ArrayRef<uint8_t>>
+WasmObjectFile::getSectionContents(DataRefImpl Sec) const {
+  const WasmSection &S = Sections[Sec.d.a];
+  // This will never fail since wasm sections can never be empty (user-sections
+  // must have a name and non-user sections each have a defined structure).
+  return S.Content;
+}
+
+uint64_t WasmObjectFile::getSectionAlignment(DataRefImpl Sec) const {
+  return 1;
+}
+
+bool WasmObjectFile::isSectionCompressed(DataRefImpl Sec) const {
+  return false;
+}
+
+bool WasmObjectFile::isSectionText(DataRefImpl Sec) const {
+  return getWasmSection(Sec).Type == wasm::WASM_SEC_CODE;
+}
+
+bool WasmObjectFile::isSectionData(DataRefImpl Sec) const {
+  return getWasmSection(Sec).Type == wasm::WASM_SEC_DATA;
+}
+
+bool WasmObjectFile::isSectionBSS(DataRefImpl Sec) const { return false; }
+
+bool WasmObjectFile::isSectionVirtual(DataRefImpl Sec) const { return false; }
+
+relocation_iterator WasmObjectFile::section_rel_begin(DataRefImpl Ref) const {
+  DataRefImpl RelocRef;
+  RelocRef.d.a = Ref.d.a;
+  RelocRef.d.b = 0;
+  return relocation_iterator(RelocationRef(RelocRef, this));
+}
+
+relocation_iterator WasmObjectFile::section_rel_end(DataRefImpl Ref) const {
+  const WasmSection &Sec = getWasmSection(Ref);
+  DataRefImpl RelocRef;
+  RelocRef.d.a = Ref.d.a;
+  RelocRef.d.b = Sec.Relocations.size();
+  return relocation_iterator(RelocationRef(RelocRef, this));
+}
+
+void WasmObjectFile::moveRelocationNext(DataRefImpl &Rel) const { Rel.d.b++; }
+
+uint64_t WasmObjectFile::getRelocationOffset(DataRefImpl Ref) const {
+  const wasm::WasmRelocation &Rel = getWasmRelocation(Ref);
+  return Rel.Offset;
+}
+
+symbol_iterator WasmObjectFile::getRelocationSymbol(DataRefImpl Ref) const {
+  const wasm::WasmRelocation &Rel = getWasmRelocation(Ref);
+  if (Rel.Type == wasm::R_WASM_TYPE_INDEX_LEB)
+    return symbol_end();
+  DataRefImpl Sym;
+  Sym.d.a = 1;
+  Sym.d.b = Rel.Index;
+  return symbol_iterator(SymbolRef(Sym, this));
+}
+
+uint64_t WasmObjectFile::getRelocationType(DataRefImpl Ref) const {
+  const wasm::WasmRelocation &Rel = getWasmRelocation(Ref);
+  return Rel.Type;
+}
+
+void WasmObjectFile::getRelocationTypeName(
+    DataRefImpl Ref, SmallVectorImpl<char> &Result) const {
+  const wasm::WasmRelocation &Rel = getWasmRelocation(Ref);
+  StringRef Res = "Unknown";
+
+#define WASM_RELOC(name, value)                                                \
+  case wasm::name:                                                             \
+    Res = #name;                                                               \
+    break;
+
+  switch (Rel.Type) {
+#include "llvm/BinaryFormat/WasmRelocs.def"
+  }
+
+#undef WASM_RELOC
+
+  Result.append(Res.begin(), Res.end());
+}
+
+section_iterator WasmObjectFile::section_begin() const {
+  DataRefImpl Ref;
+  Ref.d.a = 0;
+  return section_iterator(SectionRef(Ref, this));
+}
+
+section_iterator WasmObjectFile::section_end() const {
+  DataRefImpl Ref;
+  Ref.d.a = Sections.size();
+  return section_iterator(SectionRef(Ref, this));
+}
+
+uint8_t WasmObjectFile::getBytesInAddress() const {
+  return HasMemory64 ? 8 : 4;
+}
+
+StringRef WasmObjectFile::getFileFormatName() const { return "WASM"; }
+
+Triple::ArchType WasmObjectFile::getArch() const {
+  return HasMemory64 ? Triple::wasm64 : Triple::wasm32;
+}
+
+Expected<SubtargetFeatures> WasmObjectFile::getFeatures() const {
+  return SubtargetFeatures();
+}
+
+bool WasmObjectFile::isRelocatableObject() const { return HasLinkingSection; }
+
+bool WasmObjectFile::isSharedObject() const { return HasDylinkSection; }
+
+const WasmSection &WasmObjectFile::getWasmSection(DataRefImpl Ref) const {
+  assert(Ref.d.a < Sections.size());
+  return Sections[Ref.d.a];
+}
+
+const WasmSection &
+WasmObjectFile::getWasmSection(const SectionRef &Section) const {
+  return getWasmSection(Section.getRawDataRefImpl());
+}
+
+const wasm::WasmRelocation &
+WasmObjectFile::getWasmRelocation(const RelocationRef &Ref) const {
+  return getWasmRelocation(Ref.getRawDataRefImpl());
+}
+
+const wasm::WasmRelocation &
+WasmObjectFile::getWasmRelocation(DataRefImpl Ref) const {
+  assert(Ref.d.a < Sections.size());
+  const WasmSection &Sec = Sections[Ref.d.a];
+  assert(Ref.d.b < Sec.Relocations.size());
+  return Sec.Relocations[Ref.d.b];
+}
+
+int WasmSectionOrderChecker::getSectionOrder(unsigned ID,
+                                             StringRef CustomSectionName) {
+  switch (ID) {
+  case wasm::WASM_SEC_CUSTOM:
+    return StringSwitch<unsigned>(CustomSectionName)
+        .Case("dylink", WASM_SEC_ORDER_DYLINK)
+        .Case("dylink.0", WASM_SEC_ORDER_DYLINK)
+        .Case("linking", WASM_SEC_ORDER_LINKING)
+        .StartsWith("reloc.", WASM_SEC_ORDER_RELOC)
+        .Case("name", WASM_SEC_ORDER_NAME)
+        .Case("producers", WASM_SEC_ORDER_PRODUCERS)
+        .Case("target_features", WASM_SEC_ORDER_TARGET_FEATURES)
+        .Default(WASM_SEC_ORDER_NONE);
+  case wasm::WASM_SEC_TYPE:
+    return WASM_SEC_ORDER_TYPE;
+  case wasm::WASM_SEC_IMPORT:
+    return WASM_SEC_ORDER_IMPORT;
+  case wasm::WASM_SEC_FUNCTION:
+    return WASM_SEC_ORDER_FUNCTION;
+  case wasm::WASM_SEC_TABLE:
+    return WASM_SEC_ORDER_TABLE;
+  case wasm::WASM_SEC_MEMORY:
+    return WASM_SEC_ORDER_MEMORY;
+  case wasm::WASM_SEC_GLOBAL:
+    return WASM_SEC_ORDER_GLOBAL;
+  case wasm::WASM_SEC_EXPORT:
+    return WASM_SEC_ORDER_EXPORT;
+  case wasm::WASM_SEC_START:
+    return WASM_SEC_ORDER_START;
+  case wasm::WASM_SEC_ELEM:
+    return WASM_SEC_ORDER_ELEM;
+  case wasm::WASM_SEC_CODE:
+    return WASM_SEC_ORDER_CODE;
+  case wasm::WASM_SEC_DATA:
+    return WASM_SEC_ORDER_DATA;
+  case wasm::WASM_SEC_DATACOUNT:
+    return WASM_SEC_ORDER_DATACOUNT;
+  case wasm::WASM_SEC_TAG:
+    return WASM_SEC_ORDER_TAG;
+  default:
+    return WASM_SEC_ORDER_NONE;
+  }
+}
+
+// Represents the edges in a directed graph where any node B reachable from node
+// A is not allowed to appear before A in the section ordering, but may appear
+// afterward.
+int WasmSectionOrderChecker::DisallowedPredecessors
+    [WASM_NUM_SEC_ORDERS][WASM_NUM_SEC_ORDERS] = {
+        // WASM_SEC_ORDER_NONE
+        {},
+        // WASM_SEC_ORDER_TYPE
+        {WASM_SEC_ORDER_TYPE, WASM_SEC_ORDER_IMPORT},
+        // WASM_SEC_ORDER_IMPORT
+        {WASM_SEC_ORDER_IMPORT, WASM_SEC_ORDER_FUNCTION},
+        // WASM_SEC_ORDER_FUNCTION
+        {WASM_SEC_ORDER_FUNCTION, WASM_SEC_ORDER_TABLE},
+        // WASM_SEC_ORDER_TABLE
+        {WASM_SEC_ORDER_TABLE, WASM_SEC_ORDER_MEMORY},
+        // WASM_SEC_ORDER_MEMORY
+        {WASM_SEC_ORDER_MEMORY, WASM_SEC_ORDER_TAG},
+        // WASM_SEC_ORDER_TAG
+        {WASM_SEC_ORDER_TAG, WASM_SEC_ORDER_GLOBAL},
+        // WASM_SEC_ORDER_GLOBAL
+        {WASM_SEC_ORDER_GLOBAL, WASM_SEC_ORDER_EXPORT},
+        // WASM_SEC_ORDER_EXPORT
+        {WASM_SEC_ORDER_EXPORT, WASM_SEC_ORDER_START},
+        // WASM_SEC_ORDER_START
+        {WASM_SEC_ORDER_START, WASM_SEC_ORDER_ELEM},
+        // WASM_SEC_ORDER_ELEM
+        {WASM_SEC_ORDER_ELEM, WASM_SEC_ORDER_DATACOUNT},
+        // WASM_SEC_ORDER_DATACOUNT
+        {WASM_SEC_ORDER_DATACOUNT, WASM_SEC_ORDER_CODE},
+        // WASM_SEC_ORDER_CODE
+        {WASM_SEC_ORDER_CODE, WASM_SEC_ORDER_DATA},
+        // WASM_SEC_ORDER_DATA
+        {WASM_SEC_ORDER_DATA, WASM_SEC_ORDER_LINKING},
+
+        // Custom Sections
+        // WASM_SEC_ORDER_DYLINK
+        {WASM_SEC_ORDER_DYLINK, WASM_SEC_ORDER_TYPE},
+        // WASM_SEC_ORDER_LINKING
+        {WASM_SEC_ORDER_LINKING, WASM_SEC_ORDER_RELOC, WASM_SEC_ORDER_NAME},
+        // WASM_SEC_ORDER_RELOC (can be repeated)
+        {},
+        // WASM_SEC_ORDER_NAME
+        {WASM_SEC_ORDER_NAME, WASM_SEC_ORDER_PRODUCERS},
+        // WASM_SEC_ORDER_PRODUCERS
+        {WASM_SEC_ORDER_PRODUCERS, WASM_SEC_ORDER_TARGET_FEATURES},
+        // WASM_SEC_ORDER_TARGET_FEATURES
+        {WASM_SEC_ORDER_TARGET_FEATURES}};
+
+bool WasmSectionOrderChecker::isValidSectionOrder(unsigned ID,
+                                                  StringRef CustomSectionName) {
+  int Order = getSectionOrder(ID, CustomSectionName);
+  if (Order == WASM_SEC_ORDER_NONE)
+    return true;
+
+  // Disallowed predecessors we need to check for
+  SmallVector<int, WASM_NUM_SEC_ORDERS> WorkList;
+
+  // Keep track of completed checks to avoid repeating work
+  bool Checked[WASM_NUM_SEC_ORDERS] = {};
+
+  int Curr = Order;
+  while (true) {
+    // Add new disallowed predecessors to work list
+    for (size_t I = 0;; ++I) {
+      int Next = DisallowedPredecessors[Curr][I];
+      if (Next == WASM_SEC_ORDER_NONE)
+        break;
+      if (Checked[Next])
+        continue;
+      WorkList.push_back(Next);
+      Checked[Next] = true;
+    }
+
+    if (WorkList.empty())
+      break;
+
+    // Consider next disallowed predecessor
+    Curr = WorkList.pop_back_val();
+    if (Seen[Curr])
+      return false;
+  }
+
+  // Have not seen any disallowed predecessors
+  Seen[Order] = true;
+  return true;
+}