/build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/llvm/lib/Bitcode/Reader/BitcodeReader.cpp

Bug Summary

File:	llvm/lib/Bitcode/Reader/BitcodeReader.cpp
Warning:	line 2708, column 50 Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name BitcodeReader.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/build-llvm -resource-dir /usr/lib/llvm-15/lib/clang/15.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I lib/Bitcode/Reader -I /build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/llvm/lib/Bitcode/Reader -I include -I /build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/llvm/include -D _FORTIFY_SOURCE=2 -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-15/lib/clang/15.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/build-llvm=build-llvm -fmacro-prefix-map=/build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/= -fcoverage-prefix-map=/build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/build-llvm=build-llvm -fcoverage-prefix-map=/build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/= -O3 -Wno-unused-command-line-argument -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/build-llvm -fdebug-prefix-map=/build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/build-llvm=build-llvm -fdebug-prefix-map=/build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/= -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2022-02-09-075911-15377-1 -x c++ /build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/llvm/lib/Bitcode/Reader/BitcodeReader.cpp

/build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/llvm/lib/Bitcode/Reader/BitcodeReader.cpp

→

1//===- BitcodeReader.cpp - Internal BitcodeReader implementation ----------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//

9#include "llvm/Bitcode/BitcodeReader.h"
10#include "MetadataLoader.h"
11#include "ValueList.h"
12#include "llvm/ADT/APFloat.h"
13#include "llvm/ADT/APInt.h"
14#include "llvm/ADT/ArrayRef.h"
15#include "llvm/ADT/DenseMap.h"
16#include "llvm/ADT/Optional.h"
17#include "llvm/ADT/STLExtras.h"
18#include "llvm/ADT/SmallString.h"
19#include "llvm/ADT/SmallVector.h"
20#include "llvm/ADT/StringRef.h"
21#include "llvm/ADT/Triple.h"
22#include "llvm/ADT/Twine.h"
23#include "llvm/Bitcode/BitcodeCommon.h"
24#include "llvm/Bitcode/LLVMBitCodes.h"
25#include "llvm/Bitstream/BitstreamReader.h"
26#include "llvm/Config/llvm-config.h"
27#include "llvm/IR/Argument.h"
28#include "llvm/IR/Attributes.h"
29#include "llvm/IR/AutoUpgrade.h"
30#include "llvm/IR/BasicBlock.h"
31#include "llvm/IR/CallingConv.h"
32#include "llvm/IR/Comdat.h"
33#include "llvm/IR/Constant.h"
34#include "llvm/IR/Constants.h"
35#include "llvm/IR/DataLayout.h"
36#include "llvm/IR/DebugInfo.h"
37#include "llvm/IR/DebugInfoMetadata.h"
38#include "llvm/IR/DebugLoc.h"
39#include "llvm/IR/DerivedTypes.h"
40#include "llvm/IR/Function.h"
41#include "llvm/IR/GVMaterializer.h"
42#include "llvm/IR/GlobalAlias.h"
43#include "llvm/IR/GlobalIFunc.h"
44#include "llvm/IR/GlobalObject.h"
45#include "llvm/IR/GlobalValue.h"
46#include "llvm/IR/GlobalVariable.h"
47#include "llvm/IR/InlineAsm.h"
48#include "llvm/IR/InstIterator.h"
49#include "llvm/IR/InstrTypes.h"
50#include "llvm/IR/Instruction.h"
51#include "llvm/IR/Instructions.h"
52#include "llvm/IR/Intrinsics.h"
53#include "llvm/IR/LLVMContext.h"
54#include "llvm/IR/Metadata.h"
55#include "llvm/IR/Module.h"
56#include "llvm/IR/ModuleSummaryIndex.h"
57#include "llvm/IR/Operator.h"
58#include "llvm/IR/Type.h"
59#include "llvm/IR/Value.h"
60#include "llvm/IR/Verifier.h"
61#include "llvm/Support/AtomicOrdering.h"
62#include "llvm/Support/Casting.h"
63#include "llvm/Support/CommandLine.h"
64#include "llvm/Support/Compiler.h"
65#include "llvm/Support/Debug.h"
66#include "llvm/Support/Error.h"
67#include "llvm/Support/ErrorHandling.h"
68#include "llvm/Support/ErrorOr.h"
69#include "llvm/Support/ManagedStatic.h"
70#include "llvm/Support/MathExtras.h"
71#include "llvm/Support/MemoryBuffer.h"
72#include "llvm/Support/raw_ostream.h"
73#include <algorithm>
74#include <cassert>
75#include <cstddef>
76#include <cstdint>
77#include <deque>
78#include <map>
79#include <memory>
80#include <set>
81#include <string>
82#include <system_error>
83#include <tuple>
84#include <utility>
85#include <vector>

87using namespace llvm;

89static cl::opt<bool> PrintSummaryGUIDs(
  "print-summary-global-ids", cl::init(false), cl::Hidden,
  cl::desc(
      "Print the global id for each value when reading the module summary"));

94namespace {

96enum {
SWITCH_INST_MAGIC = 0x4B5 // May 2012 => 1205 => Hex
98};

100} // end anonymous namespace

102static Error error(const Twine &Message) {
return make_error<StringError>(
    Message, make_error_code(BitcodeError::CorruptedBitcode));
105}

107static Error hasInvalidBitcodeHeader(BitstreamCursor &Stream) {
if (!Stream.canSkipToPos(4))
  return createStringError(std::errc::illegal_byte_sequence,
                           "file too small to contain bitcode header");
for (unsigned C : {'B', 'C'})
  if (Expected<SimpleBitstreamCursor::word_t> Res = Stream.Read(8)) {
    if (Res.get() != C)
      return createStringError(std::errc::illegal_byte_sequence,
                               "file doesn't start with bitcode header");
  } else
    return Res.takeError();
for (unsigned C : {0x0, 0xC, 0xE, 0xD})
  if (Expected<SimpleBitstreamCursor::word_t> Res = Stream.Read(4)) {
    if (Res.get() != C)
      return createStringError(std::errc::illegal_byte_sequence,
                               "file doesn't start with bitcode header");
  } else
    return Res.takeError();
return Error::success();
126}

128static Expected<BitstreamCursor> initStream(MemoryBufferRef Buffer) {
const unsigned char *BufPtr = (const unsigned char *)Buffer.getBufferStart();
const unsigned char *BufEnd = BufPtr + Buffer.getBufferSize();

if (Buffer.getBufferSize() & 3)
  return error("Invalid bitcode signature");

// If we have a wrapper header, parse it and ignore the non-bc file contents.
// The magic number is 0x0B17C0DE stored in little endian.
if (isBitcodeWrapper(BufPtr, BufEnd))
  if (SkipBitcodeWrapperHeader(BufPtr, BufEnd, true))
    return error("Invalid bitcode wrapper header");

BitstreamCursor Stream(ArrayRef<uint8_t>(BufPtr, BufEnd));
if (Error Err = hasInvalidBitcodeHeader(Stream))
  return std::move(Err);

return std::move(Stream);
146}

148/// Convert a string from a record into an std::string, return true on failure.
149template <typename StrTy>
150static bool convertToString(ArrayRef<uint64_t> Record, unsigned Idx,
                          StrTy &Result) {
if (Idx > Record.size())
  return true;

Result.append(Record.begin() + Idx, Record.end());
return false;
157}

159// Strip all the TBAA attachment for the module.
160static void stripTBAA(Module *M) {
for (auto &F : *M) {
  if (F.isMaterializable())
    continue;
  for (auto &I : instructions(F))
    I.setMetadata(LLVMContext::MD_tbaa, nullptr);
}
167}

169/// Read the "IDENTIFICATION_BLOCK_ID" block, do some basic enforcement on the
170/// "epoch" encoded in the bitcode, and return the producer name if any.
171static Expected<std::string> readIdentificationBlock(BitstreamCursor &Stream) {
if (Error Err = Stream.EnterSubBlock(bitc::IDENTIFICATION_BLOCK_ID))
  return std::move(Err);

// Read all the records.
SmallVector<uint64_t, 64> Record;

std::string ProducerIdentification;

while (true) {
  BitstreamEntry Entry;
  if (Error E = Stream.advance().moveInto(Entry))
    return std::move(E);

  switch (Entry.Kind) {
  default:
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return ProducerIdentification;
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Read a record.
  Record.clear();
  Expected<unsigned> MaybeBitCode = Stream.readRecord(Entry.ID, Record);
  if (!MaybeBitCode)
    return MaybeBitCode.takeError();
  switch (MaybeBitCode.get()) {
  default: // Default behavior: reject
    return error("Invalid value");
  case bitc::IDENTIFICATION_CODE_STRING: // IDENTIFICATION: [strchr x N]
    convertToString(Record, 0, ProducerIdentification);
    break;
  case bitc::IDENTIFICATION_CODE_EPOCH: { // EPOCH: [epoch#]
    unsigned epoch = (unsigned)Record[0];
    if (epoch != bitc::BITCODE_CURRENT_EPOCH) {
      return error(
        Twine("Incompatible epoch: Bitcode '") + Twine(epoch) +
        "' vs current: '" + Twine(bitc::BITCODE_CURRENT_EPOCH) + "'");
    }
  }
  }
}
217}

219static Expected<std::string> readIdentificationCode(BitstreamCursor &Stream) {
// We expect a number of well-defined blocks, though we don't necessarily
// need to understand them all.
while (true) {
  if (Stream.AtEndOfStream())
    return "";

  BitstreamEntry Entry;
  if (Error E = Stream.advance().moveInto(Entry))
    return std::move(E);

  switch (Entry.Kind) {
  case BitstreamEntry::EndBlock:
  case BitstreamEntry::Error:
    return error("Malformed block");

  case BitstreamEntry::SubBlock:
    if (Entry.ID == bitc::IDENTIFICATION_BLOCK_ID)
      return readIdentificationBlock(Stream);

    // Ignore other sub-blocks.
    if (Error Err = Stream.SkipBlock())
      return std::move(Err);
    continue;
  case BitstreamEntry::Record:
    if (Error E = Stream.skipRecord(Entry.ID).takeError())
      return std::move(E);
    continue;
  }
}
249}

251static Expected<bool> hasObjCCategoryInModule(BitstreamCursor &Stream) {
if (Error Err = Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
  return std::move(Err);

SmallVector<uint64_t, 64> Record;
// Read all the records for this module.

while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return false;
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Read a record.
  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  switch (MaybeRecord.get()) {
  default:
    break; // Default behavior, ignore unknown content.
  case bitc::MODULE_CODE_SECTIONNAME: { // SECTIONNAME: [strchr x N]
    std::string S;
    if (convertToString(Record, 0, S))
      return error("Invalid record");
    // Check for the i386 and other (x86_64, ARM) conventions
    if (S.find("__DATA,__objc_catlist") != std::string::npos ||
        S.find("__OBJC,__category") != std::string::npos)
      return true;
    break;
  }
  }
  Record.clear();
}
llvm_unreachable("Exit infinite loop")::llvm::llvm_unreachable_internal("Exit infinite loop", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 295);
296}

298static Expected<bool> hasObjCCategory(BitstreamCursor &Stream) {
// We expect a number of well-defined blocks, though we don't necessarily
// need to understand them all.
while (true) {
  BitstreamEntry Entry;
  if (Error E = Stream.advance().moveInto(Entry))
    return std::move(E);

  switch (Entry.Kind) {
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return false;

  case BitstreamEntry::SubBlock:
    if (Entry.ID == bitc::MODULE_BLOCK_ID)
      return hasObjCCategoryInModule(Stream);

    // Ignore other sub-blocks.
    if (Error Err = Stream.SkipBlock())
      return std::move(Err);
    continue;

  case BitstreamEntry::Record:
    if (Error E = Stream.skipRecord(Entry.ID).takeError())
      return std::move(E);
    continue;
  }
}
327}

329static Expected<std::string> readModuleTriple(BitstreamCursor &Stream) {
if (Error Err = Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
  return std::move(Err);

SmallVector<uint64_t, 64> Record;

std::string Triple;

// Read all the records for this module.
while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return Triple;
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Read a record.
  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  switch (MaybeRecord.get()) {
  default: break;  // Default behavior, ignore unknown content.
  case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
    std::string S;
    if (convertToString(Record, 0, S))
      return error("Invalid record");
    Triple = S;
    break;
  }
  }
  Record.clear();
}
llvm_unreachable("Exit infinite loop")::llvm::llvm_unreachable_internal("Exit infinite loop", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 371);
372}

374static Expected<std::string> readTriple(BitstreamCursor &Stream) {
// We expect a number of well-defined blocks, though we don't necessarily
// need to understand them all.
while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advance();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return "";

  case BitstreamEntry::SubBlock:
    if (Entry.ID == bitc::MODULE_BLOCK_ID)
      return readModuleTriple(Stream);

    // Ignore other sub-blocks.
    if (Error Err = Stream.SkipBlock())
      return std::move(Err);
    continue;

  case BitstreamEntry::Record:
    if (llvm::Expected<unsigned> Skipped = Stream.skipRecord(Entry.ID))
      continue;
    else
      return Skipped.takeError();
  }
}
405}

407namespace {

409class BitcodeReaderBase {
410protected:
BitcodeReaderBase(BitstreamCursor Stream, StringRef Strtab)
    : Stream(std::move(Stream)), Strtab(Strtab) {
  this->Stream.setBlockInfo(&BlockInfo);
}

BitstreamBlockInfo BlockInfo;
BitstreamCursor Stream;
StringRef Strtab;

/// In version 2 of the bitcode we store names of global values and comdats in
/// a string table rather than in the VST.
bool UseStrtab = false;

Expected<unsigned> parseVersionRecord(ArrayRef<uint64_t> Record);

/// If this module uses a string table, pop the reference to the string table
/// and return the referenced string and the rest of the record. Otherwise
/// just return the record itself.
std::pair<StringRef, ArrayRef<uint64_t>>
readNameFromStrtab(ArrayRef<uint64_t> Record);

Error readBlockInfo();

// Contains an arbitrary and optional string identifying the bitcode producer
std::string ProducerIdentification;

Error error(const Twine &Message);
438};

440} // end anonymous namespace

442Error BitcodeReaderBase::error(const Twine &Message) {
std::string FullMsg = Message.str();
if (!ProducerIdentification.empty())
  FullMsg += " (Producer: '" + ProducerIdentification + "' Reader: 'LLVM " +
             LLVM_VERSION_STRING"15.0.0" "')";
return ::error(FullMsg);
448}

450Expected<unsigned>
451BitcodeReaderBase::parseVersionRecord(ArrayRef<uint64_t> Record) {
if (Record.empty())
  return error("Invalid record");
unsigned ModuleVersion = Record[0];
if (ModuleVersion > 2)
  return error("Invalid value");
UseStrtab = ModuleVersion >= 2;
return ModuleVersion;
459}

461std::pair<StringRef, ArrayRef<uint64_t>>
462BitcodeReaderBase::readNameFromStrtab(ArrayRef<uint64_t> Record) {
if (!UseStrtab)
  return {"", Record};
// Invalid reference. Let the caller complain about the record being empty.
if (Record[0] + Record[1] > Strtab.size())
  return {"", {}};
return {StringRef(Strtab.data() + Record[0], Record[1]), Record.slice(2)};
469}

471namespace {

473class BitcodeReader : public BitcodeReaderBase, public GVMaterializer {
LLVMContext &Context;
Module *TheModule = nullptr;
// Next offset to start scanning for lazy parsing of function bodies.
uint64_t NextUnreadBit = 0;
// Last function offset found in the VST.
uint64_t LastFunctionBlockBit = 0;
bool SeenValueSymbolTable = false;
uint64_t VSTOffset = 0;

std::vector<std::string> SectionTable;
std::vector<std::string> GCTable;

std::vector<Type*> TypeList;
DenseMap<Function *, FunctionType *> FunctionTypes;
BitcodeReaderValueList ValueList;
Optional<MetadataLoader> MDLoader;
std::vector<Comdat *> ComdatList;
DenseSet<GlobalObject *> ImplicitComdatObjects;
SmallVector<Instruction *, 64> InstructionList;

std::vector<std::pair<GlobalVariable *, unsigned>> GlobalInits;
std::vector<std::pair<GlobalValue *, unsigned>> IndirectSymbolInits;

struct FunctionOperandInfo {
  Function *F;
  unsigned PersonalityFn;
  unsigned Prefix;
  unsigned Prologue;
};
std::vector<FunctionOperandInfo> FunctionOperands;

/// The set of attributes by index.  Index zero in the file is for null, and
/// is thus not represented here.  As such all indices are off by one.
std::vector<AttributeList> MAttributes;

/// The set of attribute groups.
std::map<unsigned, AttributeList> MAttributeGroups;

/// While parsing a function body, this is a list of the basic blocks for the
/// function.
std::vector<BasicBlock*> FunctionBBs;

// When reading the module header, this list is populated with functions that
// have bodies later in the file.
std::vector<Function*> FunctionsWithBodies;

// When intrinsic functions are encountered which require upgrading they are
// stored here with their replacement function.
using UpdatedIntrinsicMap = DenseMap<Function *, Function *>;
UpdatedIntrinsicMap UpgradedIntrinsics;
// Intrinsics which were remangled because of types rename
UpdatedIntrinsicMap RemangledIntrinsics;

// Several operations happen after the module header has been read, but
// before function bodies are processed. This keeps track of whether
// we've done this yet.
bool SeenFirstFunctionBody = false;

/// When function bodies are initially scanned, this map contains info about
/// where to find deferred function body in the stream.
DenseMap<Function*, uint64_t> DeferredFunctionInfo;

/// When Metadata block is initially scanned when parsing the module, we may
/// choose to defer parsing of the metadata. This vector contains info about
/// which Metadata blocks are deferred.
std::vector<uint64_t> DeferredMetadataInfo;

/// These are basic blocks forward-referenced by block addresses.  They are
/// inserted lazily into functions when they're loaded.  The basic block ID is
/// its index into the vector.
DenseMap<Function *, std::vector<BasicBlock *>> BasicBlockFwdRefs;
std::deque<Function *> BasicBlockFwdRefQueue;

/// Indicates that we are using a new encoding for instruction operands where
/// most operands in the current FUNCTION_BLOCK are encoded relative to the
/// instruction number, for a more compact encoding.  Some instruction
/// operands are not relative to the instruction ID: basic block numbers, and
/// types. Once the old style function blocks have been phased out, we would
/// not need this flag.
bool UseRelativeIDs = false;

/// True if all functions will be materialized, negating the need to process
/// (e.g.) blockaddress forward references.
bool WillMaterializeAllForwardRefs = false;

bool StripDebugInfo = false;
TBAAVerifier TBAAVerifyHelper;

std::vector<std::string> BundleTags;
SmallVector<SyncScope::ID, 8> SSIDs;

565public:
BitcodeReader(BitstreamCursor Stream, StringRef Strtab,
              StringRef ProducerIdentification, LLVMContext &Context);

Error materializeForwardReferencedFunctions();

Error materialize(GlobalValue *GV) override;
Error materializeModule() override;
std::vector<StructType *> getIdentifiedStructTypes() const override;

/// Main interface to parsing a bitcode buffer.
/// \returns true if an error occurred.
Error parseBitcodeInto(
    Module *M, bool ShouldLazyLoadMetadata = false, bool IsImporting = false,
    DataLayoutCallbackTy DataLayoutCallback = [](StringRef) { return None; });

static uint64_t decodeSignRotatedValue(uint64_t V);

/// Materialize any deferred Metadata block.
Error materializeMetadata() override;

void setStripDebugInfo() override;

588private:
std::vector<StructType *> IdentifiedStructTypes;
StructType *createIdentifiedStructType(LLVMContext &Context, StringRef Name);
StructType *createIdentifiedStructType(LLVMContext &Context);

Type *getTypeByID(unsigned ID);

Value *getFnValueByID(unsigned ID, Type *Ty) {
  if (Ty && Ty->isMetadataTy())
    return MetadataAsValue::get(Ty->getContext(), getFnMetadataByID(ID));
  return ValueList.getValueFwdRef(ID, Ty);
}

Metadata *getFnMetadataByID(unsigned ID) {
  return MDLoader->getMetadataFwdRefOrLoad(ID);
}

BasicBlock *getBasicBlock(unsigned ID) const {
  if (ID >= FunctionBBs.size()) return nullptr; // Invalid ID
  return FunctionBBs[ID];
}

AttributeList getAttributes(unsigned i) const {
  if (i-1 < MAttributes.size())
    return MAttributes[i-1];
  return AttributeList();
}

/// Read a value/type pair out of the specified record from slot 'Slot'.
/// Increment Slot past the number of slots used in the record. Return true on
/// failure.
bool getValueTypePair(const SmallVectorImpl<uint64_t> &Record, unsigned &Slot,
                      unsigned InstNum, Value *&ResVal) {
  if (Slot == Record.size()) return true;
  unsigned ValNo = (unsigned)Record[Slot++];
  // Adjust the ValNo, if it was encoded relative to the InstNum.
  if (UseRelativeIDs)
    ValNo = InstNum - ValNo;
  if (ValNo < InstNum) {
    // If this is not a forward reference, just return the value we already
    // have.
    ResVal = getFnValueByID(ValNo, nullptr);
    return ResVal == nullptr;
  }
  if (Slot == Record.size())
    return true;

  unsigned TypeNo = (unsigned)Record[Slot++];
  ResVal = getFnValueByID(ValNo, getTypeByID(TypeNo));
  return ResVal == nullptr;
}

/// Read a value out of the specified record from slot 'Slot'. Increment Slot
/// past the number of slots used by the value in the record. Return true if
/// there is an error.
bool popValue(const SmallVectorImpl<uint64_t> &Record, unsigned &Slot,
              unsigned InstNum, Type *Ty, Value *&ResVal) {
  if (getValue(Record, Slot, InstNum, Ty, ResVal))
    return true;
  // All values currently take a single record slot.
  ++Slot;
  return false;
}

/// Like popValue, but does not increment the Slot number.
bool getValue(const SmallVectorImpl<uint64_t> &Record, unsigned Slot,
              unsigned InstNum, Type *Ty, Value *&ResVal) {
  ResVal = getValue(Record, Slot, InstNum, Ty);
  return ResVal == nullptr;
}

/// Version of getValue that returns ResVal directly, or 0 if there is an
/// error.
Value *getValue(const SmallVectorImpl<uint64_t> &Record, unsigned Slot,
                unsigned InstNum, Type *Ty) {
  if (Slot == Record.size()) return nullptr;
  unsigned ValNo = (unsigned)Record[Slot];
  // Adjust the ValNo, if it was encoded relative to the InstNum.
  if (UseRelativeIDs)
    ValNo = InstNum - ValNo;
  return getFnValueByID(ValNo, Ty);
}

/// Like getValue, but decodes signed VBRs.
Value *getValueSigned(const SmallVectorImpl<uint64_t> &Record, unsigned Slot,
                      unsigned InstNum, Type *Ty) {
  if (Slot == Record.size()) return nullptr;
  unsigned ValNo = (unsigned)decodeSignRotatedValue(Record[Slot]);
  // Adjust the ValNo, if it was encoded relative to the InstNum.
  if (UseRelativeIDs)
    ValNo = InstNum - ValNo;
  return getFnValueByID(ValNo, Ty);
}

/// Upgrades old-style typeless byval/sret/inalloca attributes by adding the
/// corresponding argument's pointee type. Also upgrades intrinsics that now
/// require an elementtype attribute.
void propagateAttributeTypes(CallBase *CB, ArrayRef<Type *> ArgsTys);

/// Converts alignment exponent (i.e. power of two (or zero)) to the
/// corresponding alignment to use. If alignment is too large, returns
/// a corresponding error code.
Error parseAlignmentValue(uint64_t Exponent, MaybeAlign &Alignment);
Error parseAttrKind(uint64_t Code, Attribute::AttrKind *Kind);
Error parseModule(
    uint64_t ResumeBit, bool ShouldLazyLoadMetadata = false,
    DataLayoutCallbackTy DataLayoutCallback = [](StringRef) { return None; });

Error parseComdatRecord(ArrayRef<uint64_t> Record);
Error parseGlobalVarRecord(ArrayRef<uint64_t> Record);
Error parseFunctionRecord(ArrayRef<uint64_t> Record);
Error parseGlobalIndirectSymbolRecord(unsigned BitCode,
                                      ArrayRef<uint64_t> Record);

Error parseAttributeBlock();
Error parseAttributeGroupBlock();
Error parseTypeTable();
Error parseTypeTableBody();
Error parseOperandBundleTags();
Error parseSyncScopeNames();

Expected<Value *> recordValue(SmallVectorImpl<uint64_t> &Record,
                              unsigned NameIndex, Triple &TT);
void setDeferredFunctionInfo(unsigned FuncBitcodeOffsetDelta, Function *F,
                             ArrayRef<uint64_t> Record);
Error parseValueSymbolTable(uint64_t Offset = 0);
Error parseGlobalValueSymbolTable();
Error parseConstants();
Error rememberAndSkipFunctionBodies();
Error rememberAndSkipFunctionBody();
/// Save the positions of the Metadata blocks and skip parsing the blocks.
Error rememberAndSkipMetadata();
Error typeCheckLoadStoreInst(Type *ValType, Type *PtrType);
Error parseFunctionBody(Function *F);
Error globalCleanup();
Error resolveGlobalAndIndirectSymbolInits();
Error parseUseLists();
Error findFunctionInStream(
    Function *F,
    DenseMap<Function *, uint64_t>::iterator DeferredFunctionInfoIterator);

SyncScope::ID getDecodedSyncScopeID(unsigned Val);
730};

732/// Class to manage reading and parsing function summary index bitcode
733/// files/sections.
734class ModuleSummaryIndexBitcodeReader : public BitcodeReaderBase {
/// The module index built during parsing.
ModuleSummaryIndex &TheIndex;

/// Indicates whether we have encountered a global value summary section
/// yet during parsing.
bool SeenGlobalValSummary = false;

/// Indicates whether we have already parsed the VST, used for error checking.
bool SeenValueSymbolTable = false;

/// Set to the offset of the VST recorded in the MODULE_CODE_VSTOFFSET record.
/// Used to enable on-demand parsing of the VST.
uint64_t VSTOffset = 0;

// Map to save ValueId to ValueInfo association that was recorded in the
// ValueSymbolTable. It is used after the VST is parsed to convert
// call graph edges read from the function summary from referencing
// callees by their ValueId to using the ValueInfo instead, which is how
// they are recorded in the summary index being built.
// We save a GUID which refers to the same global as the ValueInfo, but
// ignoring the linkage, i.e. for values other than local linkage they are
// identical.
DenseMap<unsigned, std::pair<ValueInfo, GlobalValue::GUID>>
    ValueIdToValueInfoMap;

/// Map populated during module path string table parsing, from the
/// module ID to a string reference owned by the index's module
/// path string table, used to correlate with combined index
/// summary records.
DenseMap<uint64_t, StringRef> ModuleIdMap;

/// Original source file name recorded in a bitcode record.
std::string SourceFileName;

/// The string identifier given to this module by the client, normally the
/// path to the bitcode file.
StringRef ModulePath;

/// For per-module summary indexes, the unique numerical identifier given to
/// this module by the client.
unsigned ModuleId;

777public:
ModuleSummaryIndexBitcodeReader(BitstreamCursor Stream, StringRef Strtab,
                                ModuleSummaryIndex &TheIndex,
                                StringRef ModulePath, unsigned ModuleId);

Error parseModule();

784private:
void setValueGUID(uint64_t ValueID, StringRef ValueName,
                  GlobalValue::LinkageTypes Linkage,
                  StringRef SourceFileName);
Error parseValueSymbolTable(
    uint64_t Offset,
    DenseMap<unsigned, GlobalValue::LinkageTypes> &ValueIdToLinkageMap);
std::vector<ValueInfo> makeRefList(ArrayRef<uint64_t> Record);
std::vector<FunctionSummary::EdgeTy> makeCallList(ArrayRef<uint64_t> Record,
                                                  bool IsOldProfileFormat,
                                                  bool HasProfile,
                                                  bool HasRelBF);
Error parseEntireSummary(unsigned ID);
Error parseModuleStringTable();
void parseTypeIdCompatibleVtableSummaryRecord(ArrayRef<uint64_t> Record);
void parseTypeIdCompatibleVtableInfo(ArrayRef<uint64_t> Record, size_t &Slot,
                                     TypeIdCompatibleVtableInfo &TypeId);
std::vector<FunctionSummary::ParamAccess>
parseParamAccesses(ArrayRef<uint64_t> Record);

std::pair<ValueInfo, GlobalValue::GUID>
getValueInfoFromValueId(unsigned ValueId);

void addThisModule();
ModuleSummaryIndex::ModuleInfo *getThisModule();
809};

811} // end anonymous namespace

813std::error_code llvm::errorToErrorCodeAndEmitErrors(LLVMContext &Ctx,
                                                  Error Err) {
if (Err) {
  std::error_code EC;
  handleAllErrors(std::move(Err), [&](ErrorInfoBase &EIB) {
    EC = EIB.convertToErrorCode();
    Ctx.emitError(EIB.message());
  });
  return EC;
}
return std::error_code();
824}

826BitcodeReader::BitcodeReader(BitstreamCursor Stream, StringRef Strtab,
                           StringRef ProducerIdentification,
                           LLVMContext &Context)
  : BitcodeReaderBase(std::move(Stream), Strtab), Context(Context),
    ValueList(Context, Stream.SizeInBytes()) {
this->ProducerIdentification = std::string(ProducerIdentification);
832}

834Error BitcodeReader::materializeForwardReferencedFunctions() {
if (WillMaterializeAllForwardRefs)
  return Error::success();

// Prevent recursion.
WillMaterializeAllForwardRefs = true;

while (!BasicBlockFwdRefQueue.empty()) {
  Function *F = BasicBlockFwdRefQueue.front();
  BasicBlockFwdRefQueue.pop_front();
  assert(F && "Expected valid function")(static_cast <bool> (F && "Expected valid function"
) ? void (0) : __assert_fail ("F && \"Expected valid function\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 844, __extension__
 __PRETTY_FUNCTION__));
  if (!BasicBlockFwdRefs.count(F))
    // Already materialized.
    continue;

  // Check for a function that isn't materializable to prevent an infinite
  // loop.  When parsing a blockaddress stored in a global variable, there
  // isn't a trivial way to check if a function will have a body without a
  // linear search through FunctionsWithBodies, so just check it here.
  if (!F->isMaterializable())
    return error("Never resolved function from blockaddress");

  // Try to materialize F.
  if (Error Err = materialize(F))
    return Err;
}
assert(BasicBlockFwdRefs.empty() && "Function missing from queue")(static_cast <bool> (BasicBlockFwdRefs.empty() &&
 "Function missing from queue") ? void (0) : __assert_fail ("BasicBlockFwdRefs.empty() && \"Function missing from queue\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 860, __extension__
 __PRETTY_FUNCTION__));

// Reset state.
WillMaterializeAllForwardRefs = false;
return Error::success();
865}

867//===----------------------------------------------------------------------===//
868//  Helper functions to implement forward reference resolution, etc.
869//===----------------------------------------------------------------------===//

871static bool hasImplicitComdat(size_t Val) {
switch (Val) {
default:
  return false;
case 1:  // Old WeakAnyLinkage
case 4:  // Old LinkOnceAnyLinkage
case 10: // Old WeakODRLinkage
case 11: // Old LinkOnceODRLinkage
  return true;
}
881}

883static GlobalValue::LinkageTypes getDecodedLinkage(unsigned Val) {
switch (Val) {
default: // Map unknown/new linkages to external
case 0:
  return GlobalValue::ExternalLinkage;
case 2:
  return GlobalValue::AppendingLinkage;
case 3:
  return GlobalValue::InternalLinkage;
case 5:
  return GlobalValue::ExternalLinkage; // Obsolete DLLImportLinkage
case 6:
  return GlobalValue::ExternalLinkage; // Obsolete DLLExportLinkage
case 7:
  return GlobalValue::ExternalWeakLinkage;
case 8:
  return GlobalValue::CommonLinkage;
case 9:
  return GlobalValue::PrivateLinkage;
case 12:
  return GlobalValue::AvailableExternallyLinkage;
case 13:
  return GlobalValue::PrivateLinkage; // Obsolete LinkerPrivateLinkage
case 14:
  return GlobalValue::PrivateLinkage; // Obsolete LinkerPrivateWeakLinkage
case 15:
  return GlobalValue::ExternalLinkage; // Obsolete LinkOnceODRAutoHideLinkage
case 1: // Old value with implicit comdat.
case 16:
  return GlobalValue::WeakAnyLinkage;
case 10: // Old value with implicit comdat.
case 17:
  return GlobalValue::WeakODRLinkage;
case 4: // Old value with implicit comdat.
case 18:
  return GlobalValue::LinkOnceAnyLinkage;
case 11: // Old value with implicit comdat.
case 19:
  return GlobalValue::LinkOnceODRLinkage;
}
923}

925static FunctionSummary::FFlags getDecodedFFlags(uint64_t RawFlags) {
FunctionSummary::FFlags Flags;
Flags.ReadNone = RawFlags & 0x1;
Flags.ReadOnly = (RawFlags >> 1) & 0x1;
Flags.NoRecurse = (RawFlags >> 2) & 0x1;
Flags.ReturnDoesNotAlias = (RawFlags >> 3) & 0x1;
Flags.NoInline = (RawFlags >> 4) & 0x1;
Flags.AlwaysInline = (RawFlags >> 5) & 0x1;
Flags.NoUnwind = (RawFlags >> 6) & 0x1;
Flags.MayThrow = (RawFlags >> 7) & 0x1;
Flags.HasUnknownCall = (RawFlags >> 8) & 0x1;
Flags.MustBeUnreachable = (RawFlags >> 9) & 0x1;
return Flags;
938}

940// Decode the flags for GlobalValue in the summary. The bits for each attribute:
941//
942// linkage: [0,4), notEligibleToImport: 4, live: 5, local: 6, canAutoHide: 7,
943// visibility: [8, 10).
944static GlobalValueSummary::GVFlags getDecodedGVSummaryFlags(uint64_t RawFlags,
                                                          uint64_t Version) {
// Summary were not emitted before LLVM 3.9, we don't need to upgrade Linkage
// like getDecodedLinkage() above. Any future change to the linkage enum and
// to getDecodedLinkage() will need to be taken into account here as above.
auto Linkage = GlobalValue::LinkageTypes(RawFlags & 0xF); // 4 bits
auto Visibility = GlobalValue::VisibilityTypes((RawFlags >> 8) & 3); // 2 bits
RawFlags = RawFlags >> 4;
bool NotEligibleToImport = (RawFlags & 0x1) || Version < 3;
// The Live flag wasn't introduced until version 3. For dead stripping
// to work correctly on earlier versions, we must conservatively treat all
// values as live.
bool Live = (RawFlags & 0x2) || Version < 3;
bool Local = (RawFlags & 0x4);
bool AutoHide = (RawFlags & 0x8);

return GlobalValueSummary::GVFlags(Linkage, Visibility, NotEligibleToImport,
                                   Live, Local, AutoHide);
962}

964// Decode the flags for GlobalVariable in the summary
965static GlobalVarSummary::GVarFlags getDecodedGVarFlags(uint64_t RawFlags) {
return GlobalVarSummary::GVarFlags(
    (RawFlags & 0x1) ? true : false, (RawFlags & 0x2) ? true : false,
    (RawFlags & 0x4) ? true : false,
    (GlobalObject::VCallVisibility)(RawFlags >> 3));
970}

972static GlobalValue::VisibilityTypes getDecodedVisibility(unsigned Val) {
switch (Val) {
default: // Map unknown visibilities to default.
case 0: return GlobalValue::DefaultVisibility;
case 1: return GlobalValue::HiddenVisibility;
case 2: return GlobalValue::ProtectedVisibility;
}
979}

981static GlobalValue::DLLStorageClassTypes
982getDecodedDLLStorageClass(unsigned Val) {
switch (Val) {
default: // Map unknown values to default.
case 0: return GlobalValue::DefaultStorageClass;
case 1: return GlobalValue::DLLImportStorageClass;
case 2: return GlobalValue::DLLExportStorageClass;
}
989}

991static bool getDecodedDSOLocal(unsigned Val) {
switch(Val) {
default: // Map unknown values to preemptable.
case 0:  return false;
case 1:  return true;
}
997}

999static GlobalVariable::ThreadLocalMode getDecodedThreadLocalMode(unsigned Val) {
switch (Val) {
  case 0: return GlobalVariable::NotThreadLocal;
  default: // Map unknown non-zero value to general dynamic.
  case 1: return GlobalVariable::GeneralDynamicTLSModel;
  case 2: return GlobalVariable::LocalDynamicTLSModel;
  case 3: return GlobalVariable::InitialExecTLSModel;
  case 4: return GlobalVariable::LocalExecTLSModel;
}
1008}

1010static GlobalVariable::UnnamedAddr getDecodedUnnamedAddrType(unsigned Val) {
switch (Val) {
  default: // Map unknown to UnnamedAddr::None.
  case 0: return GlobalVariable::UnnamedAddr::None;
  case 1: return GlobalVariable::UnnamedAddr::Global;
  case 2: return GlobalVariable::UnnamedAddr::Local;
}
1017}

1019static int getDecodedCastOpcode(unsigned Val) {
switch (Val) {
default: return -1;
case bitc::CAST_TRUNC   : return Instruction::Trunc;
case bitc::CAST_ZEXT    : return Instruction::ZExt;
case bitc::CAST_SEXT    : return Instruction::SExt;
case bitc::CAST_FPTOUI  : return Instruction::FPToUI;
case bitc::CAST_FPTOSI  : return Instruction::FPToSI;
case bitc::CAST_UITOFP  : return Instruction::UIToFP;
case bitc::CAST_SITOFP  : return Instruction::SIToFP;
case bitc::CAST_FPTRUNC : return Instruction::FPTrunc;
case bitc::CAST_FPEXT   : return Instruction::FPExt;
case bitc::CAST_PTRTOINT: return Instruction::PtrToInt;
case bitc::CAST_INTTOPTR: return Instruction::IntToPtr;
case bitc::CAST_BITCAST : return Instruction::BitCast;
case bitc::CAST_ADDRSPACECAST: return Instruction::AddrSpaceCast;
}
1036}

1038static int getDecodedUnaryOpcode(unsigned Val, Type *Ty) {
bool IsFP = Ty->isFPOrFPVectorTy();
// UnOps are only valid for int/fp or vector of int/fp types
if (!IsFP && !Ty->isIntOrIntVectorTy())
  return -1;

switch (Val) {
default:
  return -1;
case bitc::UNOP_FNEG:
  return IsFP ? Instruction::FNeg : -1;
}
1050}

1052static int getDecodedBinaryOpcode(unsigned Val, Type *Ty) {
bool IsFP = Ty->isFPOrFPVectorTy();
// BinOps are only valid for int/fp or vector of int/fp types
if (!IsFP && !Ty->isIntOrIntVectorTy())
  return -1;

switch (Val) {
default:
  return -1;
case bitc::BINOP_ADD:
  return IsFP ? Instruction::FAdd : Instruction::Add;
case bitc::BINOP_SUB:
  return IsFP ? Instruction::FSub : Instruction::Sub;
case bitc::BINOP_MUL:
  return IsFP ? Instruction::FMul : Instruction::Mul;
case bitc::BINOP_UDIV:
  return IsFP ? -1 : Instruction::UDiv;
case bitc::BINOP_SDIV:
  return IsFP ? Instruction::FDiv : Instruction::SDiv;
case bitc::BINOP_UREM:
  return IsFP ? -1 : Instruction::URem;
case bitc::BINOP_SREM:
  return IsFP ? Instruction::FRem : Instruction::SRem;
case bitc::BINOP_SHL:
  return IsFP ? -1 : Instruction::Shl;
case bitc::BINOP_LSHR:
  return IsFP ? -1 : Instruction::LShr;
case bitc::BINOP_ASHR:
  return IsFP ? -1 : Instruction::AShr;
case bitc::BINOP_AND:
  return IsFP ? -1 : Instruction::And;
case bitc::BINOP_OR:
  return IsFP ? -1 : Instruction::Or;
case bitc::BINOP_XOR:
  return IsFP ? -1 : Instruction::Xor;
}
1088}

1090static AtomicRMWInst::BinOp getDecodedRMWOperation(unsigned Val) {
switch (Val) {
default: return AtomicRMWInst::BAD_BINOP;
case bitc::RMW_XCHG: return AtomicRMWInst::Xchg;
case bitc::RMW_ADD: return AtomicRMWInst::Add;
case bitc::RMW_SUB: return AtomicRMWInst::Sub;
case bitc::RMW_AND: return AtomicRMWInst::And;
case bitc::RMW_NAND: return AtomicRMWInst::Nand;
case bitc::RMW_OR: return AtomicRMWInst::Or;
case bitc::RMW_XOR: return AtomicRMWInst::Xor;
case bitc::RMW_MAX: return AtomicRMWInst::Max;
case bitc::RMW_MIN: return AtomicRMWInst::Min;
case bitc::RMW_UMAX: return AtomicRMWInst::UMax;
case bitc::RMW_UMIN: return AtomicRMWInst::UMin;
case bitc::RMW_FADD: return AtomicRMWInst::FAdd;
case bitc::RMW_FSUB: return AtomicRMWInst::FSub;
}
1107}

1109static AtomicOrdering getDecodedOrdering(unsigned Val) {
switch (Val) {
case bitc::ORDERING_NOTATOMIC: return AtomicOrdering::NotAtomic;
case bitc::ORDERING_UNORDERED: return AtomicOrdering::Unordered;
case bitc::ORDERING_MONOTONIC: return AtomicOrdering::Monotonic;
case bitc::ORDERING_ACQUIRE: return AtomicOrdering::Acquire;
case bitc::ORDERING_RELEASE: return AtomicOrdering::Release;
case bitc::ORDERING_ACQREL: return AtomicOrdering::AcquireRelease;
default: // Map unknown orderings to sequentially-consistent.
case bitc::ORDERING_SEQCST: return AtomicOrdering::SequentiallyConsistent;
}
1120}

1122static Comdat::SelectionKind getDecodedComdatSelectionKind(unsigned Val) {
switch (Val) {
default: // Map unknown selection kinds to any.
case bitc::COMDAT_SELECTION_KIND_ANY:
  return Comdat::Any;
case bitc::COMDAT_SELECTION_KIND_EXACT_MATCH:
  return Comdat::ExactMatch;
case bitc::COMDAT_SELECTION_KIND_LARGEST:
  return Comdat::Largest;
case bitc::COMDAT_SELECTION_KIND_NO_DUPLICATES:
  return Comdat::NoDeduplicate;
case bitc::COMDAT_SELECTION_KIND_SAME_SIZE:
  return Comdat::SameSize;
}
1136}

1138static FastMathFlags getDecodedFastMathFlags(unsigned Val) {
FastMathFlags FMF;
if (0 != (Val & bitc::UnsafeAlgebra))
  FMF.setFast();
if (0 != (Val & bitc::AllowReassoc))
  FMF.setAllowReassoc();
if (0 != (Val & bitc::NoNaNs))
  FMF.setNoNaNs();
if (0 != (Val & bitc::NoInfs))
  FMF.setNoInfs();
if (0 != (Val & bitc::NoSignedZeros))
  FMF.setNoSignedZeros();
if (0 != (Val & bitc::AllowReciprocal))
  FMF.setAllowReciprocal();
if (0 != (Val & bitc::AllowContract))
  FMF.setAllowContract(true);
if (0 != (Val & bitc::ApproxFunc))
  FMF.setApproxFunc();
return FMF;
1157}

1159static void upgradeDLLImportExportLinkage(GlobalValue *GV, unsigned Val) {
switch (Val) {
case 5: GV->setDLLStorageClass(GlobalValue::DLLImportStorageClass); break;
case 6: GV->setDLLStorageClass(GlobalValue::DLLExportStorageClass); break;
}
1164}

1166Type *BitcodeReader::getTypeByID(unsigned ID) {
// The type table size is always specified correctly.
if (ID >= TypeList.size())
  return nullptr;

if (Type *Ty = TypeList[ID])
  return Ty;

// If we have a forward reference, the only possible case is when it is to a
// named struct.  Just create a placeholder for now.
return TypeList[ID] = createIdentifiedStructType(Context);
1177}

1179StructType *BitcodeReader::createIdentifiedStructType(LLVMContext &Context,
                                                    StringRef Name) {
auto *Ret = StructType::create(Context, Name);
IdentifiedStructTypes.push_back(Ret);
return Ret;
1184}

1186StructType *BitcodeReader::createIdentifiedStructType(LLVMContext &Context) {
auto *Ret = StructType::create(Context);
IdentifiedStructTypes.push_back(Ret);
return Ret;
1190}

1192//===----------------------------------------------------------------------===//
1193//  Functions for parsing blocks from the bitcode file
1194//===----------------------------------------------------------------------===//

1196static uint64_t getRawAttributeMask(Attribute::AttrKind Val) {
switch (Val) {
case Attribute::EndAttrKinds:
case Attribute::EmptyKey:
case Attribute::TombstoneKey:
  llvm_unreachable("Synthetic enumerators which should never get here")::llvm::llvm_unreachable_internal("Synthetic enumerators which should never get here"
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 1201);

case Attribute::None:            return 0;
case Attribute::ZExt:            return 1 << 0;
case Attribute::SExt:            return 1 << 1;
case Attribute::NoReturn:        return 1 << 2;
case Attribute::InReg:           return 1 << 3;
case Attribute::StructRet:       return 1 << 4;
case Attribute::NoUnwind:        return 1 << 5;
case Attribute::NoAlias:         return 1 << 6;
case Attribute::ByVal:           return 1 << 7;
case Attribute::Nest:            return 1 << 8;
case Attribute::ReadNone:        return 1 << 9;
case Attribute::ReadOnly:        return 1 << 10;
case Attribute::NoInline:        return 1 << 11;
case Attribute::AlwaysInline:    return 1 << 12;
case Attribute::OptimizeForSize: return 1 << 13;
case Attribute::StackProtect:    return 1 << 14;
case Attribute::StackProtectReq: return 1 << 15;
case Attribute::Alignment:       return 31 << 16;
case Attribute::NoCapture:       return 1 << 21;
case Attribute::NoRedZone:       return 1 << 22;
case Attribute::NoImplicitFloat: return 1 << 23;
case Attribute::Naked:           return 1 << 24;
case Attribute::InlineHint:      return 1 << 25;
case Attribute::StackAlignment:  return 7 << 26;
case Attribute::ReturnsTwice:    return 1 << 29;
case Attribute::UWTable:         return 1 << 30;
case Attribute::NonLazyBind:     return 1U << 31;
case Attribute::SanitizeAddress: return 1ULL << 32;
case Attribute::MinSize:         return 1ULL << 33;
case Attribute::NoDuplicate:     return 1ULL << 34;
case Attribute::StackProtectStrong: return 1ULL << 35;
case Attribute::SanitizeThread:  return 1ULL << 36;
case Attribute::SanitizeMemory:  return 1ULL << 37;
case Attribute::NoBuiltin:       return 1ULL << 38;
case Attribute::Returned:        return 1ULL << 39;
case Attribute::Cold:            return 1ULL << 40;
case Attribute::Builtin:         return 1ULL << 41;
case Attribute::OptimizeNone:    return 1ULL << 42;
case Attribute::InAlloca:        return 1ULL << 43;
case Attribute::NonNull:         return 1ULL << 44;
case Attribute::JumpTable:       return 1ULL << 45;
case Attribute::Convergent:      return 1ULL << 46;
case Attribute::SafeStack:       return 1ULL << 47;
case Attribute::NoRecurse:       return 1ULL << 48;
case Attribute::InaccessibleMemOnly:         return 1ULL << 49;
case Attribute::InaccessibleMemOrArgMemOnly: return 1ULL << 50;
case Attribute::SwiftSelf:       return 1ULL << 51;
case Attribute::SwiftError:      return 1ULL << 52;
case Attribute::WriteOnly:       return 1ULL << 53;
case Attribute::Speculatable:    return 1ULL << 54;
case Attribute::StrictFP:        return 1ULL << 55;
case Attribute::SanitizeHWAddress: return 1ULL << 56;
case Attribute::NoCfCheck:       return 1ULL << 57;
case Attribute::OptForFuzzing:   return 1ULL << 58;
case Attribute::ShadowCallStack: return 1ULL << 59;
case Attribute::SpeculativeLoadHardening:
  return 1ULL << 60;
case Attribute::ImmArg:
  return 1ULL << 61;
case Attribute::WillReturn:
  return 1ULL << 62;
case Attribute::NoFree:
  return 1ULL << 63;
default:
  // Other attributes are not supported in the raw format,
  // as we ran out of space.
  return 0;
}
llvm_unreachable("Unsupported attribute type")::llvm::llvm_unreachable_internal("Unsupported attribute type"
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 1271);
1272}

1274static void addRawAttributeValue(AttrBuilder &B, uint64_t Val) {
if (!Val) return;

for (Attribute::AttrKind I = Attribute::None; I != Attribute::EndAttrKinds;
     I = Attribute::AttrKind(I + 1)) {
  if (uint64_t A = (Val & getRawAttributeMask(I))) {
    if (I == Attribute::Alignment)
      B.addAlignmentAttr(1ULL << ((A >> 16) - 1));
    else if (I == Attribute::StackAlignment)
      B.addStackAlignmentAttr(1ULL << ((A >> 26)-1));
    else if (Attribute::isTypeAttrKind(I))
      B.addTypeAttr(I, nullptr); // Type will be auto-upgraded.
    else
      B.addAttribute(I);
  }
}
1290}

1292/// This fills an AttrBuilder object with the LLVM attributes that have
1293/// been decoded from the given integer. This function must stay in sync with
1294/// 'encodeLLVMAttributesForBitcode'.
1295static void decodeLLVMAttributesForBitcode(AttrBuilder &B,
                                         uint64_t EncodedAttrs) {
// The alignment is stored as a 16-bit raw value from bits 31--16.  We shift
// the bits above 31 down by 11 bits.
unsigned Alignment = (EncodedAttrs & (0xffffULL << 16)) >> 16;
assert((!Alignment || isPowerOf2_32(Alignment)) &&(static_cast <bool> ((!Alignment || isPowerOf2_32(Alignment
)) && "Alignment must be a power of two.") ? void (0)
 : __assert_fail ("(!Alignment || isPowerOf2_32(Alignment)) && \"Alignment must be a power of two.\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 1301, __extension__
 __PRETTY_FUNCTION__))
       "Alignment must be a power of two.")(static_cast <bool> ((!Alignment || isPowerOf2_32(Alignment
)) && "Alignment must be a power of two.") ? void (0)
 : __assert_fail ("(!Alignment || isPowerOf2_32(Alignment)) && \"Alignment must be a power of two.\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 1301, __extension__
 __PRETTY_FUNCTION__));

if (Alignment)
  B.addAlignmentAttr(Alignment);
addRawAttributeValue(B, ((EncodedAttrs & (0xfffffULL << 32)) >> 11) |
                        (EncodedAttrs & 0xffff));
1307}

1309Error BitcodeReader::parseAttributeBlock() {
if (Error Err = Stream.EnterSubBlock(bitc::PARAMATTR_BLOCK_ID))
  return Err;

if (!MAttributes.empty())
  return error("Invalid multiple blocks");

SmallVector<uint64_t, 64> Record;

SmallVector<AttributeList, 8> Attrs;

// Read all the records.
while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return Error::success();
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Read a record.
  Record.clear();
  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  switch (MaybeRecord.get()) {
  default:  // Default behavior: ignore.
    break;
  case bitc::PARAMATTR_CODE_ENTRY_OLD: // ENTRY: [paramidx0, attr0, ...]
    // Deprecated, but still needed to read old bitcode files.
    if (Record.size() & 1)
      return error("Invalid record");

    for (unsigned i = 0, e = Record.size(); i != e; i += 2) {
      AttrBuilder B(Context);
      decodeLLVMAttributesForBitcode(B, Record[i+1]);
      Attrs.push_back(AttributeList::get(Context, Record[i], B));
    }

    MAttributes.push_back(AttributeList::get(Context, Attrs));
    Attrs.clear();
    break;
  case bitc::PARAMATTR_CODE_ENTRY: // ENTRY: [attrgrp0, attrgrp1, ...]
    for (unsigned i = 0, e = Record.size(); i != e; ++i)
      Attrs.push_back(MAttributeGroups[Record[i]]);

    MAttributes.push_back(AttributeList::get(Context, Attrs));
    Attrs.clear();
    break;
  }
}
1369}

1371// Returns Attribute::None on unrecognized codes.
1372static Attribute::AttrKind getAttrFromCode(uint64_t Code) {
switch (Code) {
default:
  return Attribute::None;
case bitc::ATTR_KIND_ALIGNMENT:
  return Attribute::Alignment;
case bitc::ATTR_KIND_ALWAYS_INLINE:
  return Attribute::AlwaysInline;
case bitc::ATTR_KIND_ARGMEMONLY:
  return Attribute::ArgMemOnly;
case bitc::ATTR_KIND_BUILTIN:
  return Attribute::Builtin;
case bitc::ATTR_KIND_BY_VAL:
  return Attribute::ByVal;
case bitc::ATTR_KIND_IN_ALLOCA:
  return Attribute::InAlloca;
case bitc::ATTR_KIND_COLD:
  return Attribute::Cold;
case bitc::ATTR_KIND_CONVERGENT:
  return Attribute::Convergent;
case bitc::ATTR_KIND_DISABLE_SANITIZER_INSTRUMENTATION:
  return Attribute::DisableSanitizerInstrumentation;
case bitc::ATTR_KIND_ELEMENTTYPE:
  return Attribute::ElementType;
case bitc::ATTR_KIND_INACCESSIBLEMEM_ONLY:
  return Attribute::InaccessibleMemOnly;
case bitc::ATTR_KIND_INACCESSIBLEMEM_OR_ARGMEMONLY:
  return Attribute::InaccessibleMemOrArgMemOnly;
case bitc::ATTR_KIND_INLINE_HINT:
  return Attribute::InlineHint;
case bitc::ATTR_KIND_IN_REG:
  return Attribute::InReg;
case bitc::ATTR_KIND_JUMP_TABLE:
  return Attribute::JumpTable;
case bitc::ATTR_KIND_MIN_SIZE:
  return Attribute::MinSize;
case bitc::ATTR_KIND_NAKED:
  return Attribute::Naked;
case bitc::ATTR_KIND_NEST:
  return Attribute::Nest;
case bitc::ATTR_KIND_NO_ALIAS:
  return Attribute::NoAlias;
case bitc::ATTR_KIND_NO_BUILTIN:
  return Attribute::NoBuiltin;
case bitc::ATTR_KIND_NO_CALLBACK:
  return Attribute::NoCallback;
case bitc::ATTR_KIND_NO_CAPTURE:
  return Attribute::NoCapture;
case bitc::ATTR_KIND_NO_DUPLICATE:
  return Attribute::NoDuplicate;
case bitc::ATTR_KIND_NOFREE:
  return Attribute::NoFree;
case bitc::ATTR_KIND_NO_IMPLICIT_FLOAT:
  return Attribute::NoImplicitFloat;
case bitc::ATTR_KIND_NO_INLINE:
  return Attribute::NoInline;
case bitc::ATTR_KIND_NO_RECURSE:
  return Attribute::NoRecurse;
case bitc::ATTR_KIND_NO_MERGE:
  return Attribute::NoMerge;
case bitc::ATTR_KIND_NON_LAZY_BIND:
  return Attribute::NonLazyBind;
case bitc::ATTR_KIND_NON_NULL:
  return Attribute::NonNull;
case bitc::ATTR_KIND_DEREFERENCEABLE:
  return Attribute::Dereferenceable;
case bitc::ATTR_KIND_DEREFERENCEABLE_OR_NULL:
  return Attribute::DereferenceableOrNull;
case bitc::ATTR_KIND_ALLOC_SIZE:
  return Attribute::AllocSize;
case bitc::ATTR_KIND_NO_RED_ZONE:
  return Attribute::NoRedZone;
case bitc::ATTR_KIND_NO_RETURN:
  return Attribute::NoReturn;
case bitc::ATTR_KIND_NOSYNC:
  return Attribute::NoSync;
case bitc::ATTR_KIND_NOCF_CHECK:
  return Attribute::NoCfCheck;
case bitc::ATTR_KIND_NO_PROFILE:
  return Attribute::NoProfile;
case bitc::ATTR_KIND_NO_UNWIND:
  return Attribute::NoUnwind;
case bitc::ATTR_KIND_NO_SANITIZE_COVERAGE:
  return Attribute::NoSanitizeCoverage;
case bitc::ATTR_KIND_NULL_POINTER_IS_VALID:
  return Attribute::NullPointerIsValid;
case bitc::ATTR_KIND_OPT_FOR_FUZZING:
  return Attribute::OptForFuzzing;
case bitc::ATTR_KIND_OPTIMIZE_FOR_SIZE:
  return Attribute::OptimizeForSize;
case bitc::ATTR_KIND_OPTIMIZE_NONE:
  return Attribute::OptimizeNone;
case bitc::ATTR_KIND_READ_NONE:
  return Attribute::ReadNone;
case bitc::ATTR_KIND_READ_ONLY:
  return Attribute::ReadOnly;
case bitc::ATTR_KIND_RETURNED:
  return Attribute::Returned;
case bitc::ATTR_KIND_RETURNS_TWICE:
  return Attribute::ReturnsTwice;
case bitc::ATTR_KIND_S_EXT:
  return Attribute::SExt;
case bitc::ATTR_KIND_SPECULATABLE:
  return Attribute::Speculatable;
case bitc::ATTR_KIND_STACK_ALIGNMENT:
  return Attribute::StackAlignment;
case bitc::ATTR_KIND_STACK_PROTECT:
  return Attribute::StackProtect;
case bitc::ATTR_KIND_STACK_PROTECT_REQ:
  return Attribute::StackProtectReq;
case bitc::ATTR_KIND_STACK_PROTECT_STRONG:
  return Attribute::StackProtectStrong;
case bitc::ATTR_KIND_SAFESTACK:
  return Attribute::SafeStack;
case bitc::ATTR_KIND_SHADOWCALLSTACK:
  return Attribute::ShadowCallStack;
case bitc::ATTR_KIND_STRICT_FP:
  return Attribute::StrictFP;
case bitc::ATTR_KIND_STRUCT_RET:
  return Attribute::StructRet;
case bitc::ATTR_KIND_SANITIZE_ADDRESS:
  return Attribute::SanitizeAddress;
case bitc::ATTR_KIND_SANITIZE_HWADDRESS:
  return Attribute::SanitizeHWAddress;
case bitc::ATTR_KIND_SANITIZE_THREAD:
  return Attribute::SanitizeThread;
case bitc::ATTR_KIND_SANITIZE_MEMORY:
  return Attribute::SanitizeMemory;
case bitc::ATTR_KIND_SPECULATIVE_LOAD_HARDENING:
  return Attribute::SpeculativeLoadHardening;
case bitc::ATTR_KIND_SWIFT_ERROR:
  return Attribute::SwiftError;
case bitc::ATTR_KIND_SWIFT_SELF:
  return Attribute::SwiftSelf;
case bitc::ATTR_KIND_SWIFT_ASYNC:
  return Attribute::SwiftAsync;
case bitc::ATTR_KIND_UW_TABLE:
  return Attribute::UWTable;
case bitc::ATTR_KIND_VSCALE_RANGE:
  return Attribute::VScaleRange;
case bitc::ATTR_KIND_WILLRETURN:
  return Attribute::WillReturn;
case bitc::ATTR_KIND_WRITEONLY:
  return Attribute::WriteOnly;
case bitc::ATTR_KIND_Z_EXT:
  return Attribute::ZExt;
case bitc::ATTR_KIND_IMMARG:
  return Attribute::ImmArg;
case bitc::ATTR_KIND_SANITIZE_MEMTAG:
  return Attribute::SanitizeMemTag;
case bitc::ATTR_KIND_PREALLOCATED:
  return Attribute::Preallocated;
case bitc::ATTR_KIND_NOUNDEF:
  return Attribute::NoUndef;
case bitc::ATTR_KIND_BYREF:
  return Attribute::ByRef;
case bitc::ATTR_KIND_MUSTPROGRESS:
  return Attribute::MustProgress;
case bitc::ATTR_KIND_HOT:
  return Attribute::Hot;
}
1533}

1535Error BitcodeReader::parseAlignmentValue(uint64_t Exponent,
                                       MaybeAlign &Alignment) {
// Note: Alignment in bitcode files is incremented by 1, so that zero
// can be used for default alignment.
if (Exponent > Value::MaxAlignmentExponent + 1)
  return error("Invalid alignment value");
Alignment = decodeMaybeAlign(Exponent);
return Error::success();
1543}

1545Error BitcodeReader::parseAttrKind(uint64_t Code, Attribute::AttrKind *Kind) {
*Kind = getAttrFromCode(Code);
if (*Kind == Attribute::None)
  return error("Unknown attribute kind (" + Twine(Code) + ")");
return Error::success();
1550}

1552Error BitcodeReader::parseAttributeGroupBlock() {
if (Error Err = Stream.EnterSubBlock(bitc::PARAMATTR_GROUP_BLOCK_ID))
  return Err;

if (!MAttributeGroups.empty())
  return error("Invalid multiple blocks");

SmallVector<uint64_t, 64> Record;

// Read all the records.
while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return Error::success();
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Read a record.
  Record.clear();
  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  switch (MaybeRecord.get()) {
  default:  // Default behavior: ignore.
    break;
  case bitc::PARAMATTR_GRP_CODE_ENTRY: { // ENTRY: [grpid, idx, a0, a1, ...]
    if (Record.size() < 3)
      return error("Invalid record");

    uint64_t GrpID = Record[0];
    uint64_t Idx = Record[1]; // Index of the object this attribute refers to.

    AttrBuilder B(Context);
    for (unsigned i = 2, e = Record.size(); i != e; ++i) {
      if (Record[i] == 0) {        // Enum attribute
        Attribute::AttrKind Kind;
        if (Error Err = parseAttrKind(Record[++i], &Kind))
          return Err;

        // Upgrade old-style byval attribute to one with a type, even if it's
        // nullptr. We will have to insert the real type when we associate
        // this AttributeList with a function.
        if (Kind == Attribute::ByVal)
          B.addByValAttr(nullptr);
        else if (Kind == Attribute::StructRet)
          B.addStructRetAttr(nullptr);
        else if (Kind == Attribute::InAlloca)
          B.addInAllocaAttr(nullptr);
        else if (Attribute::isEnumAttrKind(Kind))
          B.addAttribute(Kind);
        else
          return error("Not an enum attribute");
      } else if (Record[i] == 1) { // Integer attribute
        Attribute::AttrKind Kind;
        if (Error Err = parseAttrKind(Record[++i], &Kind))
          return Err;
        if (!Attribute::isIntAttrKind(Kind))
          return error("Not an int attribute");
        if (Kind == Attribute::Alignment)
          B.addAlignmentAttr(Record[++i]);
        else if (Kind == Attribute::StackAlignment)
          B.addStackAlignmentAttr(Record[++i]);
        else if (Kind == Attribute::Dereferenceable)
          B.addDereferenceableAttr(Record[++i]);
        else if (Kind == Attribute::DereferenceableOrNull)
          B.addDereferenceableOrNullAttr(Record[++i]);
        else if (Kind == Attribute::AllocSize)
          B.addAllocSizeAttrFromRawRepr(Record[++i]);
        else if (Kind == Attribute::VScaleRange)
          B.addVScaleRangeAttrFromRawRepr(Record[++i]);
      } else if (Record[i] == 3 || Record[i] == 4) { // String attribute
        bool HasValue = (Record[i++] == 4);
        SmallString<64> KindStr;
        SmallString<64> ValStr;

        while (Record[i] != 0 && i != e)
          KindStr += Record[i++];
        assert(Record[i] == 0 && "Kind string not null terminated")(static_cast <bool> (Record[i] == 0 && "Kind string not null terminated"
) ? void (0) : __assert_fail ("Record[i] == 0 && \"Kind string not null terminated\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 1639, __extension__
 __PRETTY_FUNCTION__));

        if (HasValue) {
          // Has a value associated with it.
          ++i; // Skip the '0' that terminates the "kind" string.
          while (Record[i] != 0 && i != e)
            ValStr += Record[i++];
          assert(Record[i] == 0 && "Value string not null terminated")(static_cast <bool> (Record[i] == 0 && "Value string not null terminated"
) ? void (0) : __assert_fail ("Record[i] == 0 && \"Value string not null terminated\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 1646, __extension__
 __PRETTY_FUNCTION__));
        }

        B.addAttribute(KindStr.str(), ValStr.str());
      } else if (Record[i] == 5 || Record[i] == 6) {
        bool HasType = Record[i] == 6;
        Attribute::AttrKind Kind;
        if (Error Err = parseAttrKind(Record[++i], &Kind))
          return Err;
        if (!Attribute::isTypeAttrKind(Kind))
          return error("Not a type attribute");

        B.addTypeAttr(Kind, HasType ? getTypeByID(Record[++i]) : nullptr);
      } else {
        return error("Invalid attribute group entry");
      }
    }

    UpgradeAttributes(B);
    MAttributeGroups[GrpID] = AttributeList::get(Context, Idx, B);
    break;
  }
  }
}
1670}

1672Error BitcodeReader::parseTypeTable() {
if (Error Err = Stream.EnterSubBlock(bitc::TYPE_BLOCK_ID_NEW))
  return Err;

return parseTypeTableBody();
1677}

1679Error BitcodeReader::parseTypeTableBody() {
if (!TypeList.empty())
  return error("Invalid multiple blocks");

SmallVector<uint64_t, 64> Record;
unsigned NumRecords = 0;

SmallString<64> TypeName;

// Read all the records for this type table.
while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    if (NumRecords != TypeList.size())
      return error("Malformed block");
    return Error::success();
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Read a record.
  Record.clear();
  Type *ResultTy = nullptr;
  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  switch (MaybeRecord.get()) {
  default:
    return error("Invalid value");
  case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
    // TYPE_CODE_NUMENTRY contains a count of the number of types in the
    // type list.  This allows us to reserve space.
    if (Record.empty())
      return error("Invalid record");
    TypeList.resize(Record[0]);
    continue;
  case bitc::TYPE_CODE_VOID:      // VOID
    ResultTy = Type::getVoidTy(Context);
    break;
  case bitc::TYPE_CODE_HALF:     // HALF
    ResultTy = Type::getHalfTy(Context);
    break;
  case bitc::TYPE_CODE_BFLOAT:    // BFLOAT
    ResultTy = Type::getBFloatTy(Context);
    break;
  case bitc::TYPE_CODE_FLOAT:     // FLOAT
    ResultTy = Type::getFloatTy(Context);
    break;
  case bitc::TYPE_CODE_DOUBLE:    // DOUBLE
    ResultTy = Type::getDoubleTy(Context);
    break;
  case bitc::TYPE_CODE_X86_FP80:  // X86_FP80
    ResultTy = Type::getX86_FP80Ty(Context);
    break;
  case bitc::TYPE_CODE_FP128:     // FP128
    ResultTy = Type::getFP128Ty(Context);
    break;
  case bitc::TYPE_CODE_PPC_FP128: // PPC_FP128
    ResultTy = Type::getPPC_FP128Ty(Context);
    break;
  case bitc::TYPE_CODE_LABEL:     // LABEL
    ResultTy = Type::getLabelTy(Context);
    break;
  case bitc::TYPE_CODE_METADATA:  // METADATA
    ResultTy = Type::getMetadataTy(Context);
    break;
  case bitc::TYPE_CODE_X86_MMX:   // X86_MMX
    ResultTy = Type::getX86_MMXTy(Context);
    break;
  case bitc::TYPE_CODE_X86_AMX:   // X86_AMX
    ResultTy = Type::getX86_AMXTy(Context);
    break;
  case bitc::TYPE_CODE_TOKEN:     // TOKEN
    ResultTy = Type::getTokenTy(Context);
    break;
  case bitc::TYPE_CODE_INTEGER: { // INTEGER: [width]
    if (Record.empty())
      return error("Invalid record");

    uint64_t NumBits = Record[0];
    if (NumBits < IntegerType::MIN_INT_BITS ||
        NumBits > IntegerType::MAX_INT_BITS)
      return error("Bitwidth for integer type out of range");
    ResultTy = IntegerType::get(Context, NumBits);
    break;
  }
  case bitc::TYPE_CODE_POINTER: { // POINTER: [pointee type] or
                                  //          [pointee type, address space]
    if (Record.empty())
      return error("Invalid record");
    unsigned AddressSpace = 0;
    if (Record.size() == 2)
      AddressSpace = Record[1];
    ResultTy = getTypeByID(Record[0]);
    if (!ResultTy ||
        !PointerType::isValidElementType(ResultTy))
      return error("Invalid type");
    ResultTy = PointerType::get(ResultTy, AddressSpace);
    break;
  }
  case bitc::TYPE_CODE_OPAQUE_POINTER: { // OPAQUE_POINTER: [addrspace]
    if (Record.size() != 1)
      return error("Invalid record");
    if (Context.supportsTypedPointers())
      return error(
          "Opaque pointers are only supported in -opaque-pointers mode");
    unsigned AddressSpace = Record[0];
    ResultTy = PointerType::get(Context, AddressSpace);
    break;
  }
  case bitc::TYPE_CODE_FUNCTION_OLD: {
    // Deprecated, but still needed to read old bitcode files.
    // FUNCTION: [vararg, attrid, retty, paramty x N]
    if (Record.size() < 3)
      return error("Invalid record");
    SmallVector<Type*, 8> ArgTys;
    for (unsigned i = 3, e = Record.size(); i != e; ++i) {
      if (Type *T = getTypeByID(Record[i]))
        ArgTys.push_back(T);
      else
        break;
    }

    ResultTy = getTypeByID(Record[2]);
    if (!ResultTy || ArgTys.size() < Record.size()-3)
      return error("Invalid type");

    ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
    break;
  }
  case bitc::TYPE_CODE_FUNCTION: {
    // FUNCTION: [vararg, retty, paramty x N]
    if (Record.size() < 2)
      return error("Invalid record");
    SmallVector<Type*, 8> ArgTys;
    for (unsigned i = 2, e = Record.size(); i != e; ++i) {
      if (Type *T = getTypeByID(Record[i])) {
        if (!FunctionType::isValidArgumentType(T))
          return error("Invalid function argument type");
        ArgTys.push_back(T);
      }
      else
        break;
    }

    ResultTy = getTypeByID(Record[1]);
    if (!ResultTy || ArgTys.size() < Record.size()-2)
      return error("Invalid type");

    ResultTy = FunctionType::get(ResultTy, ArgTys, Record[0]);
    break;
  }
  case bitc::TYPE_CODE_STRUCT_ANON: {  // STRUCT: [ispacked, eltty x N]
    if (Record.empty())
      return error("Invalid record");
    SmallVector<Type*, 8> EltTys;
    for (unsigned i = 1, e = Record.size(); i != e; ++i) {
      if (Type *T = getTypeByID(Record[i]))
        EltTys.push_back(T);
      else
        break;
    }
    if (EltTys.size() != Record.size()-1)
      return error("Invalid type");
    ResultTy = StructType::get(Context, EltTys, Record[0]);
    break;
  }
  case bitc::TYPE_CODE_STRUCT_NAME:   // STRUCT_NAME: [strchr x N]
    if (convertToString(Record, 0, TypeName))
      return error("Invalid record");
    continue;

  case bitc::TYPE_CODE_STRUCT_NAMED: { // STRUCT: [ispacked, eltty x N]
    if (Record.empty())
      return error("Invalid record");

    if (NumRecords >= TypeList.size())
      return error("Invalid TYPE table");

    // Check to see if this was forward referenced, if so fill in the temp.
    StructType *Res = cast_or_null<StructType>(TypeList[NumRecords]);
    if (Res) {
      Res->setName(TypeName);
      TypeList[NumRecords] = nullptr;
    } else  // Otherwise, create a new struct.
      Res = createIdentifiedStructType(Context, TypeName);
    TypeName.clear();

    SmallVector<Type*, 8> EltTys;
    for (unsigned i = 1, e = Record.size(); i != e; ++i) {
      if (Type *T = getTypeByID(Record[i]))
        EltTys.push_back(T);
      else
        break;
    }
    if (EltTys.size() != Record.size()-1)
      return error("Invalid record");
    Res->setBody(EltTys, Record[0]);
    ResultTy = Res;
    break;
  }
  case bitc::TYPE_CODE_OPAQUE: {       // OPAQUE: []
    if (Record.size() != 1)
      return error("Invalid record");

    if (NumRecords >= TypeList.size())
      return error("Invalid TYPE table");

    // Check to see if this was forward referenced, if so fill in the temp.
    StructType *Res = cast_or_null<StructType>(TypeList[NumRecords]);
    if (Res) {
      Res->setName(TypeName);
      TypeList[NumRecords] = nullptr;
    } else  // Otherwise, create a new struct with no body.
      Res = createIdentifiedStructType(Context, TypeName);
    TypeName.clear();
    ResultTy = Res;
    break;
  }
  case bitc::TYPE_CODE_ARRAY:     // ARRAY: [numelts, eltty]
    if (Record.size() < 2)
      return error("Invalid record");
    ResultTy = getTypeByID(Record[1]);
    if (!ResultTy || !ArrayType::isValidElementType(ResultTy))
      return error("Invalid type");
    ResultTy = ArrayType::get(ResultTy, Record[0]);
    break;
  case bitc::TYPE_CODE_VECTOR:    // VECTOR: [numelts, eltty] or
                                  //         [numelts, eltty, scalable]
    if (Record.size() < 2)
      return error("Invalid record");
    if (Record[0] == 0)
      return error("Invalid vector length");
    ResultTy = getTypeByID(Record[1]);
    if (!ResultTy || !VectorType::isValidElementType(ResultTy))
      return error("Invalid type");
    bool Scalable = Record.size() > 2 ? Record[2] : false;
    ResultTy = VectorType::get(ResultTy, Record[0], Scalable);
    break;
  }

  if (NumRecords >= TypeList.size())
    return error("Invalid TYPE table");
  if (TypeList[NumRecords])
    return error(
        "Invalid TYPE table: Only named structs can be forward referenced");
  assert(ResultTy && "Didn't read a type?")(static_cast <bool> (ResultTy && "Didn't read a type?"
) ? void (0) : __assert_fail ("ResultTy && \"Didn't read a type?\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 1934, __extension__
 __PRETTY_FUNCTION__));
  TypeList[NumRecords++] = ResultTy;
}
1937}

1939Error BitcodeReader::parseOperandBundleTags() {
if (Error Err = Stream.EnterSubBlock(bitc::OPERAND_BUNDLE_TAGS_BLOCK_ID))
  return Err;

if (!BundleTags.empty())
  return error("Invalid multiple blocks");

SmallVector<uint64_t, 64> Record;

while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return Error::success();
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Tags are implicitly mapped to integers by their order.

  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  if (MaybeRecord.get() != bitc::OPERAND_BUNDLE_TAG)
    return error("Invalid record");

  // OPERAND_BUNDLE_TAG: [strchr x N]
  BundleTags.emplace_back();
  if (convertToString(Record, 0, BundleTags.back()))
    return error("Invalid record");
  Record.clear();
}
1979}

1981Error BitcodeReader::parseSyncScopeNames() {
if (Error Err = Stream.EnterSubBlock(bitc::SYNC_SCOPE_NAMES_BLOCK_ID))
  return Err;

if (!SSIDs.empty())
  return error("Invalid multiple synchronization scope names blocks");

SmallVector<uint64_t, 64> Record;
while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    if (SSIDs.empty())
      return error("Invalid empty synchronization scope names block");
    return Error::success();
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Synchronization scope names are implicitly mapped to synchronization
  // scope IDs by their order.

  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  if (MaybeRecord.get() != bitc::SYNC_SCOPE_NAME)
    return error("Invalid record");

  SmallString<16> SSN;
  if (convertToString(Record, 0, SSN))
    return error("Invalid record");

  SSIDs.push_back(Context.getOrInsertSyncScopeID(SSN));
  Record.clear();
}
2024}

2026/// Associate a value with its name from the given index in the provided record.
2027Expected<Value *> BitcodeReader::recordValue(SmallVectorImpl<uint64_t> &Record,
                                           unsigned NameIndex, Triple &TT) {
SmallString<128> ValueName;
if (convertToString(Record, NameIndex, ValueName))
  return error("Invalid record");
unsigned ValueID = Record[0];
if (ValueID >= ValueList.size() || !ValueList[ValueID])
  return error("Invalid record");
Value *V = ValueList[ValueID];

StringRef NameStr(ValueName.data(), ValueName.size());
if (NameStr.find_first_of(0) != StringRef::npos)
  return error("Invalid value name");
V->setName(NameStr);
auto *GO = dyn_cast<GlobalObject>(V);
if (GO && ImplicitComdatObjects.contains(GO) && TT.supportsCOMDAT())
  GO->setComdat(TheModule->getOrInsertComdat(V->getName()));
return V;
2045}

2047/// Helper to note and return the current location, and jump to the given
2048/// offset.
2049static Expected<uint64_t> jumpToValueSymbolTable(uint64_t Offset,
                                               BitstreamCursor &Stream) {
// Save the current parsing location so we can jump back at the end
// of the VST read.
uint64_t CurrentBit = Stream.GetCurrentBitNo();
if (Error JumpFailed = Stream.JumpToBit(Offset * 32))
  return std::move(JumpFailed);
Expected<BitstreamEntry> MaybeEntry = Stream.advance();
if (!MaybeEntry)
  return MaybeEntry.takeError();
if (MaybeEntry.get().Kind != BitstreamEntry::SubBlock ||
    MaybeEntry.get().ID != bitc::VALUE_SYMTAB_BLOCK_ID)
  return error("Expected value symbol table subblock");
return CurrentBit;
2063}

2065void BitcodeReader::setDeferredFunctionInfo(unsigned FuncBitcodeOffsetDelta,
                                          Function *F,
                                          ArrayRef<uint64_t> Record) {
// Note that we subtract 1 here because the offset is relative to one word
// before the start of the identification or module block, which was
// historically always the start of the regular bitcode header.
uint64_t FuncWordOffset = Record[1] - 1;
uint64_t FuncBitOffset = FuncWordOffset * 32;
DeferredFunctionInfo[F] = FuncBitOffset + FuncBitcodeOffsetDelta;
// Set the LastFunctionBlockBit to point to the last function block.
// Later when parsing is resumed after function materialization,
// we can simply skip that last function block.
if (FuncBitOffset > LastFunctionBlockBit)
  LastFunctionBlockBit = FuncBitOffset;
2079}

2081/// Read a new-style GlobalValue symbol table.
2082Error BitcodeReader::parseGlobalValueSymbolTable() {
unsigned FuncBitcodeOffsetDelta =
    Stream.getAbbrevIDWidth() + bitc::BlockIDWidth;

if (Error Err = Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
  return Err;

SmallVector<uint64_t, 64> Record;
while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock:
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return Error::success();
  case BitstreamEntry::Record:
    break;
  }

  Record.clear();
  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  switch (MaybeRecord.get()) {
  case bitc::VST_CODE_FNENTRY: { // [valueid, offset]
    unsigned ValueID = Record[0];
    if (ValueID >= ValueList.size() || !ValueList[ValueID])
      return error("Invalid value reference in symbol table");
    setDeferredFunctionInfo(FuncBitcodeOffsetDelta,
                            cast<Function>(ValueList[ValueID]), Record);
    break;
  }
  }
}
2121}

2123/// Parse the value symbol table at either the current parsing location or
2124/// at the given bit offset if provided.
2125Error BitcodeReader::parseValueSymbolTable(uint64_t Offset) {
uint64_t CurrentBit;
// Pass in the Offset to distinguish between calling for the module-level
// VST (where we want to jump to the VST offset) and the function-level
// VST (where we don't).
if (Offset > 0) {
  Expected<uint64_t> MaybeCurrentBit = jumpToValueSymbolTable(Offset, Stream);
  if (!MaybeCurrentBit)
    return MaybeCurrentBit.takeError();
  CurrentBit = MaybeCurrentBit.get();
  // If this module uses a string table, read this as a module-level VST.
  if (UseStrtab) {
    if (Error Err = parseGlobalValueSymbolTable())
      return Err;
    if (Error JumpFailed = Stream.JumpToBit(CurrentBit))
      return JumpFailed;
    return Error::success();
  }
  // Otherwise, the VST will be in a similar format to a function-level VST,
  // and will contain symbol names.
}

// Compute the delta between the bitcode indices in the VST (the word offset
// to the word-aligned ENTER_SUBBLOCK for the function block, and that
// expected by the lazy reader. The reader's EnterSubBlock expects to have
// already read the ENTER_SUBBLOCK code (size getAbbrevIDWidth) and BlockID
// (size BlockIDWidth). Note that we access the stream's AbbrevID width here
// just before entering the VST subblock because: 1) the EnterSubBlock
// changes the AbbrevID width; 2) the VST block is nested within the same
// outer MODULE_BLOCK as the FUNCTION_BLOCKs and therefore have the same
// AbbrevID width before calling EnterSubBlock; and 3) when we want to
// jump to the FUNCTION_BLOCK using this offset later, we don't want
// to rely on the stream's AbbrevID width being that of the MODULE_BLOCK.
unsigned FuncBitcodeOffsetDelta =
    Stream.getAbbrevIDWidth() + bitc::BlockIDWidth;

if (Error Err = Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
  return Err;

SmallVector<uint64_t, 64> Record;

Triple TT(TheModule->getTargetTriple());

// Read all the records for this value table.
SmallString<128> ValueName;

while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    if (Offset > 0)
      if (Error JumpFailed = Stream.JumpToBit(CurrentBit))
        return JumpFailed;
    return Error::success();
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Read a record.
  Record.clear();
  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  switch (MaybeRecord.get()) {
  default:  // Default behavior: unknown type.
    break;
  case bitc::VST_CODE_ENTRY: {  // VST_CODE_ENTRY: [valueid, namechar x N]
    Expected<Value *> ValOrErr = recordValue(Record, 1, TT);
    if (Error Err = ValOrErr.takeError())
      return Err;
    ValOrErr.get();
    break;
  }
  case bitc::VST_CODE_FNENTRY: {
    // VST_CODE_FNENTRY: [valueid, offset, namechar x N]
    Expected<Value *> ValOrErr = recordValue(Record, 2, TT);
    if (Error Err = ValOrErr.takeError())
      return Err;
    Value *V = ValOrErr.get();

    // Ignore function offsets emitted for aliases of functions in older
    // versions of LLVM.
    if (auto *F = dyn_cast<Function>(V))
      setDeferredFunctionInfo(FuncBitcodeOffsetDelta, F, Record);
    break;
  }
  case bitc::VST_CODE_BBENTRY: {
    if (convertToString(Record, 1, ValueName))
      return error("Invalid record");
    BasicBlock *BB = getBasicBlock(Record[0]);
    if (!BB)
      return error("Invalid record");

    BB->setName(StringRef(ValueName.data(), ValueName.size()));
    ValueName.clear();
    break;
  }
  }
}
2232}

2234/// Decode a signed value stored with the sign bit in the LSB for dense VBR
2235/// encoding.
2236uint64_t BitcodeReader::decodeSignRotatedValue(uint64_t V) {
if ((V & 1) == 0)
  return V >> 1;
if (V != 1)
  return -(V >> 1);
// There is no such thing as -0 with integers.  "-0" really means MININT.
return 1ULL << 63;
2243}

2245/// Resolve all of the initializers for global values and aliases that we can.
2246Error BitcodeReader::resolveGlobalAndIndirectSymbolInits() {
std::vector<std::pair<GlobalVariable *, unsigned>> GlobalInitWorklist;
std::vector<std::pair<GlobalValue *, unsigned>> IndirectSymbolInitWorklist;
std::vector<FunctionOperandInfo> FunctionOperandWorklist;

GlobalInitWorklist.swap(GlobalInits);
IndirectSymbolInitWorklist.swap(IndirectSymbolInits);
FunctionOperandWorklist.swap(FunctionOperands);

while (!GlobalInitWorklist.empty()) {
  unsigned ValID = GlobalInitWorklist.back().second;
  if (ValID >= ValueList.size()) {
    // Not ready to resolve this yet, it requires something later in the file.
    GlobalInits.push_back(GlobalInitWorklist.back());
  } else {
    if (Constant *C = dyn_cast_or_null<Constant>(ValueList[ValID]))
      GlobalInitWorklist.back().first->setInitializer(C);
    else
      return error("Expected a constant");
  }
  GlobalInitWorklist.pop_back();
}

while (!IndirectSymbolInitWorklist.empty()) {
  unsigned ValID = IndirectSymbolInitWorklist.back().second;
  if (ValID >= ValueList.size()) {
    IndirectSymbolInits.push_back(IndirectSymbolInitWorklist.back());
  } else {
    Constant *C = dyn_cast_or_null<Constant>(ValueList[ValID]);
    if (!C)
      return error("Expected a constant");
    GlobalValue *GV = IndirectSymbolInitWorklist.back().first;
    if (auto *GA = dyn_cast<GlobalAlias>(GV)) {
      if (C->getType() != GV->getType())
        return error("Alias and aliasee types don't match");
      GA->setAliasee(C);
    } else if (auto *GI = dyn_cast<GlobalIFunc>(GV)) {
      Type *ResolverFTy =
          GlobalIFunc::getResolverFunctionType(GI->getValueType());
      // Transparently fix up the type for compatiblity with older bitcode
      GI->setResolver(
          ConstantExpr::getBitCast(C, ResolverFTy->getPointerTo()));
    } else {
      return error("Expected an alias or an ifunc");
    }
  }
  IndirectSymbolInitWorklist.pop_back();
}

while (!FunctionOperandWorklist.empty()) {
  FunctionOperandInfo &Info = FunctionOperandWorklist.back();
  if (Info.PersonalityFn) {
    unsigned ValID = Info.PersonalityFn - 1;
    if (ValID < ValueList.size()) {
      if (Constant *C = dyn_cast_or_null<Constant>(ValueList[ValID]))
        Info.F->setPersonalityFn(C);
      else
        return error("Expected a constant");
      Info.PersonalityFn = 0;
    }
  }
  if (Info.Prefix) {
    unsigned ValID = Info.Prefix - 1;
    if (ValID < ValueList.size()) {
      if (Constant *C = dyn_cast_or_null<Constant>(ValueList[ValID]))
        Info.F->setPrefixData(C);
      else
        return error("Expected a constant");
      Info.Prefix = 0;
    }
  }
  if (Info.Prologue) {
    unsigned ValID = Info.Prologue - 1;
    if (ValID < ValueList.size()) {
      if (Constant *C = dyn_cast_or_null<Constant>(ValueList[ValID]))
        Info.F->setPrologueData(C);
      else
        return error("Expected a constant");
      Info.Prologue = 0;
    }
  }
  if (Info.PersonalityFn || Info.Prefix || Info.Prologue)
    FunctionOperands.push_back(Info);
  FunctionOperandWorklist.pop_back();
}

return Error::success();
2333}

2335APInt llvm::readWideAPInt(ArrayRef<uint64_t> Vals, unsigned TypeBits) {
SmallVector<uint64_t, 8> Words(Vals.size());
transform(Vals, Words.begin(),
               BitcodeReader::decodeSignRotatedValue);

return APInt(TypeBits, Words);
2341}

2343Error BitcodeReader::parseConstants() {
if (Error Err = Stream.EnterSubBlock(bitc::CONSTANTS_BLOCK_ID))
1
Assuming the condition is false→
2
←
Taking false branch→
  return Err;

SmallVector<uint64_t, 64> Record;

// Read all the records for this value table.
Type *CurTy = Type::getInt32Ty(Context);
unsigned NextCstNo = ValueList.size();

struct DelayedShufTy {
  VectorType *OpTy;
  VectorType *RTy;
  uint64_t Op0Idx;
  uint64_t Op1Idx;
  uint64_t Op2Idx;
  unsigned CstNo;
};
std::vector<DelayedShufTy> DelayedShuffles;
struct DelayedSelTy {
  Type *OpTy;
  uint64_t Op0Idx;
  uint64_t Op1Idx;
  uint64_t Op2Idx;
  unsigned CstNo;
};
std::vector<DelayedSelTy> DelayedSelectors;

while (true) {
3
←
Loop condition is true.  Entering loop body→
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
4
←
Calling 'Expected::operator bool'→
7
←
Returning from 'Expected::operator bool'→
8
←
Taking false branch→
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
9
←
Control jumps to 'case Record:'  at line 2434→
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    // Once all the constants have been read, go through and resolve forward
    // references.
    //
    // We have to treat shuffles specially because they don't have three
    // operands anymore.  We need to convert the shuffle mask into an array,
    // and we can't convert a forward reference.
    for (auto &DelayedShuffle : DelayedShuffles) {
      VectorType *OpTy = DelayedShuffle.OpTy;
      VectorType *RTy = DelayedShuffle.RTy;
      uint64_t Op0Idx = DelayedShuffle.Op0Idx;
      uint64_t Op1Idx = DelayedShuffle.Op1Idx;
      uint64_t Op2Idx = DelayedShuffle.Op2Idx;
      uint64_t CstNo = DelayedShuffle.CstNo;
      Constant *Op0 = ValueList.getConstantFwdRef(Op0Idx, OpTy);
      Constant *Op1 = ValueList.getConstantFwdRef(Op1Idx, OpTy);
      Type *ShufTy =
          VectorType::get(Type::getInt32Ty(Context), RTy->getElementCount());
      Constant *Op2 = ValueList.getConstantFwdRef(Op2Idx, ShufTy);
      if (!ShuffleVectorInst::isValidOperands(Op0, Op1, Op2))
        return error("Invalid shufflevector operands");
      SmallVector<int, 16> Mask;
      ShuffleVectorInst::getShuffleMask(Op2, Mask);
      Value *V = ConstantExpr::getShuffleVector(Op0, Op1, Mask);
      ValueList.assignValue(V, CstNo);
    }
    for (auto &DelayedSelector : DelayedSelectors) {
      Type *OpTy = DelayedSelector.OpTy;
      Type *SelectorTy = Type::getInt1Ty(Context);
      uint64_t Op0Idx = DelayedSelector.Op0Idx;
      uint64_t Op1Idx = DelayedSelector.Op1Idx;
      uint64_t Op2Idx = DelayedSelector.Op2Idx;
      uint64_t CstNo = DelayedSelector.CstNo;
      Constant *Op1 = ValueList.getConstantFwdRef(Op1Idx, OpTy);
      Constant *Op2 = ValueList.getConstantFwdRef(Op2Idx, OpTy);
      // The selector might be an i1 or an <n x i1>
      // Get the type from the ValueList before getting a forward ref.
      if (VectorType *VTy = dyn_cast<VectorType>(OpTy)) {
        Value *V = ValueList[Op0Idx];
        assert(V)(static_cast <bool> (V) ? void (0) : __assert_fail ("V"
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 2420, __extension__
 __PRETTY_FUNCTION__));
        if (SelectorTy != V->getType())
          SelectorTy = VectorType::get(SelectorTy, VTy->getElementCount());
      }
      Constant *Op0 = ValueList.getConstantFwdRef(Op0Idx, SelectorTy);
      Value *V = ConstantExpr::getSelect(Op0, Op1, Op2);
      ValueList.assignValue(V, CstNo);
    }

    if (NextCstNo != ValueList.size())
      return error("Invalid constant reference");

    ValueList.resolveConstantForwardRefs();
    return Error::success();
  case BitstreamEntry::Record:
    // The interesting case.
    break;
10
←
 Execution continues on line 2440→
  }

  // Read a record.
  Record.clear();
  Type *VoidType = Type::getVoidTy(Context);
  Value *V = nullptr;
  Expected<unsigned> MaybeBitCode = Stream.readRecord(Entry.ID, Record);
  if (!MaybeBitCode)
11
←
Calling 'Expected::operator bool'→
14
←
Returning from 'Expected::operator bool'→
15
←
Taking false branch→
    return MaybeBitCode.takeError();
  switch (unsigned BitCode = MaybeBitCode.get()) {
16
←
Control jumps to 'case CST_CODE_CE_INBOUNDS_GEP:'  at line 2675→
  default:  // Default behavior: unknown constant
  case bitc::CST_CODE_UNDEF:     // UNDEF
    V = UndefValue::get(CurTy);
    break;
  case bitc::CST_CODE_POISON:    // POISON
    V = PoisonValue::get(CurTy);
    break;
  case bitc::CST_CODE_SETTYPE:   // SETTYPE: [typeid]
    if (Record.empty())
      return error("Invalid record");
    if (Record[0] >= TypeList.size() || !TypeList[Record[0]])
      return error("Invalid record");
    if (TypeList[Record[0]] == VoidType)
      return error("Invalid constant type");
    CurTy = TypeList[Record[0]];
    continue;  // Skip the ValueList manipulation.
  case bitc::CST_CODE_NULL:      // NULL
    if (CurTy->isVoidTy() || CurTy->isFunctionTy() || CurTy->isLabelTy())
      return error("Invalid type for a constant null value");
    V = Constant::getNullValue(CurTy);
    break;
  case bitc::CST_CODE_INTEGER:   // INTEGER: [intval]
    if (!CurTy->isIntegerTy() || Record.empty())
      return error("Invalid record");
    V = ConstantInt::get(CurTy, decodeSignRotatedValue(Record[0]));
    break;
  case bitc::CST_CODE_WIDE_INTEGER: {// WIDE_INTEGER: [n x intval]
    if (!CurTy->isIntegerTy() || Record.empty())
      return error("Invalid record");

    APInt VInt =
        readWideAPInt(Record, cast<IntegerType>(CurTy)->getBitWidth());
    V = ConstantInt::get(Context, VInt);

    break;
  }
  case bitc::CST_CODE_FLOAT: {    // FLOAT: [fpval]
    if (Record.empty())
      return error("Invalid record");
    if (CurTy->isHalfTy())
      V = ConstantFP::get(Context, APFloat(APFloat::IEEEhalf(),
                                           APInt(16, (uint16_t)Record[0])));
    else if (CurTy->isBFloatTy())
      V = ConstantFP::get(Context, APFloat(APFloat::BFloat(),
                                           APInt(16, (uint32_t)Record[0])));
    else if (CurTy->isFloatTy())
      V = ConstantFP::get(Context, APFloat(APFloat::IEEEsingle(),
                                           APInt(32, (uint32_t)Record[0])));
    else if (CurTy->isDoubleTy())
      V = ConstantFP::get(Context, APFloat(APFloat::IEEEdouble(),
                                           APInt(64, Record[0])));
    else if (CurTy->isX86_FP80Ty()) {
      // Bits are not stored the same way as a normal i80 APInt, compensate.
      uint64_t Rearrange[2];
      Rearrange[0] = (Record[1] & 0xffffLL) | (Record[0] << 16);
      Rearrange[1] = Record[0] >> 48;
      V = ConstantFP::get(Context, APFloat(APFloat::x87DoubleExtended(),
                                           APInt(80, Rearrange)));
    } else if (CurTy->isFP128Ty())
      V = ConstantFP::get(Context, APFloat(APFloat::IEEEquad(),
                                           APInt(128, Record)));
    else if (CurTy->isPPC_FP128Ty())
      V = ConstantFP::get(Context, APFloat(APFloat::PPCDoubleDouble(),
                                           APInt(128, Record)));
    else
      V = UndefValue::get(CurTy);
    break;
  }

  case bitc::CST_CODE_AGGREGATE: {// AGGREGATE: [n x value number]
    if (Record.empty())
      return error("Invalid record");

    unsigned Size = Record.size();
    SmallVector<Constant*, 16> Elts;

    if (StructType *STy = dyn_cast<StructType>(CurTy)) {
      for (unsigned i = 0; i != Size; ++i)
        Elts.push_back(ValueList.getConstantFwdRef(Record[i],
                                                   STy->getElementType(i)));
      V = ConstantStruct::get(STy, Elts);
    } else if (ArrayType *ATy = dyn_cast<ArrayType>(CurTy)) {
      Type *EltTy = ATy->getElementType();
      for (unsigned i = 0; i != Size; ++i)
        Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
      V = ConstantArray::get(ATy, Elts);
    } else if (VectorType *VTy = dyn_cast<VectorType>(CurTy)) {
      Type *EltTy = VTy->getElementType();
      for (unsigned i = 0; i != Size; ++i)
        Elts.push_back(ValueList.getConstantFwdRef(Record[i], EltTy));
      V = ConstantVector::get(Elts);
    } else {
      V = UndefValue::get(CurTy);
    }
    break;
  }
  case bitc::CST_CODE_STRING:    // STRING: [values]
  case bitc::CST_CODE_CSTRING: { // CSTRING: [values]
    if (Record.empty())
      return error("Invalid record");

    SmallString<16> Elts(Record.begin(), Record.end());
    V = ConstantDataArray::getString(Context, Elts,
                                     BitCode == bitc::CST_CODE_CSTRING);
    break;
  }
  case bitc::CST_CODE_DATA: {// DATA: [n x value]
    if (Record.empty())
      return error("Invalid record");

    Type *EltTy;
    if (auto *Array = dyn_cast<ArrayType>(CurTy))
      EltTy = Array->getElementType();
    else
      EltTy = cast<VectorType>(CurTy)->getElementType();
    if (EltTy->isIntegerTy(8)) {
      SmallVector<uint8_t, 16> Elts(Record.begin(), Record.end());
      if (isa<VectorType>(CurTy))
        V = ConstantDataVector::get(Context, Elts);
      else
        V = ConstantDataArray::get(Context, Elts);
    } else if (EltTy->isIntegerTy(16)) {
      SmallVector<uint16_t, 16> Elts(Record.begin(), Record.end());
      if (isa<VectorType>(CurTy))
        V = ConstantDataVector::get(Context, Elts);
      else
        V = ConstantDataArray::get(Context, Elts);
    } else if (EltTy->isIntegerTy(32)) {
      SmallVector<uint32_t, 16> Elts(Record.begin(), Record.end());
      if (isa<VectorType>(CurTy))
        V = ConstantDataVector::get(Context, Elts);
      else
        V = ConstantDataArray::get(Context, Elts);
    } else if (EltTy->isIntegerTy(64)) {
      SmallVector<uint64_t, 16> Elts(Record.begin(), Record.end());
      if (isa<VectorType>(CurTy))
        V = ConstantDataVector::get(Context, Elts);
      else
        V = ConstantDataArray::get(Context, Elts);
    } else if (EltTy->isHalfTy()) {
      SmallVector<uint16_t, 16> Elts(Record.begin(), Record.end());
      if (isa<VectorType>(CurTy))
        V = ConstantDataVector::getFP(EltTy, Elts);
      else
        V = ConstantDataArray::getFP(EltTy, Elts);
    } else if (EltTy->isBFloatTy()) {
      SmallVector<uint16_t, 16> Elts(Record.begin(), Record.end());
      if (isa<VectorType>(CurTy))
        V = ConstantDataVector::getFP(EltTy, Elts);
      else
        V = ConstantDataArray::getFP(EltTy, Elts);
    } else if (EltTy->isFloatTy()) {
      SmallVector<uint32_t, 16> Elts(Record.begin(), Record.end());
      if (isa<VectorType>(CurTy))
        V = ConstantDataVector::getFP(EltTy, Elts);
      else
        V = ConstantDataArray::getFP(EltTy, Elts);
    } else if (EltTy->isDoubleTy()) {
      SmallVector<uint64_t, 16> Elts(Record.begin(), Record.end());
      if (isa<VectorType>(CurTy))
        V = ConstantDataVector::getFP(EltTy, Elts);
      else
        V = ConstantDataArray::getFP(EltTy, Elts);
    } else {
      return error("Invalid type for value");
    }
    break;
  }
  case bitc::CST_CODE_CE_UNOP: {  // CE_UNOP: [opcode, opval]
    if (Record.size() < 2)
      return error("Invalid record");
    int Opc = getDecodedUnaryOpcode(Record[0], CurTy);
    if (Opc < 0) {
      V = UndefValue::get(CurTy);  // Unknown unop.
    } else {
      Constant *LHS = ValueList.getConstantFwdRef(Record[1], CurTy);
      unsigned Flags = 0;
      V = ConstantExpr::get(Opc, LHS, Flags);
    }
    break;
  }
  case bitc::CST_CODE_CE_BINOP: {  // CE_BINOP: [opcode, opval, opval]
    if (Record.size() < 3)
      return error("Invalid record");
    int Opc = getDecodedBinaryOpcode(Record[0], CurTy);
    if (Opc < 0) {
      V = UndefValue::get(CurTy);  // Unknown binop.
    } else {
      Constant *LHS = ValueList.getConstantFwdRef(Record[1], CurTy);
      Constant *RHS = ValueList.getConstantFwdRef(Record[2], CurTy);
      unsigned Flags = 0;
      if (Record.size() >= 4) {
        if (Opc == Instruction::Add ||
            Opc == Instruction::Sub ||
            Opc == Instruction::Mul ||
            Opc == Instruction::Shl) {
          if (Record[3] & (1 << bitc::OBO_NO_SIGNED_WRAP))
            Flags |= OverflowingBinaryOperator::NoSignedWrap;
          if (Record[3] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
            Flags |= OverflowingBinaryOperator::NoUnsignedWrap;
        } else if (Opc == Instruction::SDiv ||
                   Opc == Instruction::UDiv ||
                   Opc == Instruction::LShr ||
                   Opc == Instruction::AShr) {
          if (Record[3] & (1 << bitc::PEO_EXACT))
            Flags |= SDivOperator::IsExact;
        }
      }
      V = ConstantExpr::get(Opc, LHS, RHS, Flags);
    }
    break;
  }
  case bitc::CST_CODE_CE_CAST: {  // CE_CAST: [opcode, opty, opval]
    if (Record.size() < 3)
      return error("Invalid record");
    int Opc = getDecodedCastOpcode(Record[0]);
    if (Opc < 0) {
      V = UndefValue::get(CurTy);  // Unknown cast.
    } else {
      Type *OpTy = getTypeByID(Record[1]);
      if (!OpTy)
        return error("Invalid record");
      Constant *Op = ValueList.getConstantFwdRef(Record[2], OpTy);
      V = UpgradeBitCastExpr(Opc, Op, CurTy);
      if (!V) V = ConstantExpr::getCast(Opc, Op, CurTy);
    }
    break;
  }
  case bitc::CST_CODE_CE_INBOUNDS_GEP: // [ty, n x operands]
  case bitc::CST_CODE_CE_GEP: // [ty, n x operands]
  case bitc::CST_CODE_CE_GEP_WITH_INRANGE_INDEX: { // [ty, flags, n x
                                                   // operands]
    unsigned OpNum = 0;
    Type *PointeeType = nullptr;
    if (BitCode16.1
'BitCode' is not equal to CST_CODE_CE_GEP_WITH_INRANGE_INDEX
1
'BitCode' is not equal to CST_CODE_CE_GEP_WITH_INRANGE_INDEX
 == bitc::CST_CODE_CE_GEP_WITH_INRANGE_INDEX ||
18
←
Taking false branch→
        Record.size() % 2)
17
←
Assuming the condition is false→
      PointeeType = getTypeByID(Record[OpNum++]);

    bool InBounds = false;
    Optional<unsigned> InRangeIndex;
    if (BitCode18.1
'BitCode' is not equal to CST_CODE_CE_GEP_WITH_INRANGE_INDEX
1
'BitCode' is not equal to CST_CODE_CE_GEP_WITH_INRANGE_INDEX
 == bitc::CST_CODE_CE_GEP_WITH_INRANGE_INDEX) {
19
←
Taking false branch→
      uint64_t Op = Record[OpNum++];
      InBounds = Op & 1;
      InRangeIndex = Op >> 1;
    } else if (BitCode19.1
'BitCode' is equal to CST_CODE_CE_INBOUNDS_GEP
1
'BitCode' is equal to CST_CODE_CE_INBOUNDS_GEP
 == bitc::CST_CODE_CE_INBOUNDS_GEP)
20
←
Taking true branch→
      InBounds = true;

    SmallVector<Constant*, 16> Elts;
    Type *Elt0FullTy = nullptr;
21
←
'Elt0FullTy' initialized to a null pointer value→
    while (OpNum != Record.size()) {
22
←
Assuming the condition is false→
23
←
Loop condition is false. Execution continues on line 2705→
      if (!Elt0FullTy)
        Elt0FullTy = getTypeByID(Record[OpNum]);
      Type *ElTy = getTypeByID(Record[OpNum++]);
      if (!ElTy)
        return error("Invalid record");
      Elts.push_back(ValueList.getConstantFwdRef(Record[OpNum++], ElTy));
    }

    if (Elts.size() < 1)
24
←
Assuming the condition is false→
25
←
Taking false branch→
      return error("Invalid gep with no operands");

    PointerType *OrigPtrTy = cast<PointerType>(Elt0FullTy->getScalarType());
26
←
Called C++ object pointer is null
    if (!PointeeType)
      PointeeType = OrigPtrTy->getPointerElementType();
    else if (!OrigPtrTy->isOpaqueOrPointeeTypeMatches(PointeeType))
      return error("Explicit gep operator type does not match pointee type "
                   "of pointer operand");

    ArrayRef<Constant *> Indices(Elts.begin() + 1, Elts.end());
    V = ConstantExpr::getGetElementPtr(PointeeType, Elts[0], Indices,
                                       InBounds, InRangeIndex);
    break;
  }
  case bitc::CST_CODE_CE_SELECT: {  // CE_SELECT: [opval#, opval#, opval#]
    if (Record.size() < 3)
      return error("Invalid record");

    DelayedSelectors.push_back(
        {CurTy, Record[0], Record[1], Record[2], NextCstNo});
    (void)ValueList.getConstantFwdRef(NextCstNo, CurTy);
    ++NextCstNo;
    continue;
  }
  case bitc::CST_CODE_CE_EXTRACTELT
      : { // CE_EXTRACTELT: [opty, opval, opty, opval]
    if (Record.size() < 3)
      return error("Invalid record");
    VectorType *OpTy =
      dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
    if (!OpTy)
      return error("Invalid record");
    Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
    Constant *Op1 = nullptr;
    if (Record.size() == 4) {
      Type *IdxTy = getTypeByID(Record[2]);
      if (!IdxTy)
        return error("Invalid record");
      Op1 = ValueList.getConstantFwdRef(Record[3], IdxTy);
    } else {
      // Deprecated, but still needed to read old bitcode files.
      Op1 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
    }
    if (!Op1)
      return error("Invalid record");
    V = ConstantExpr::getExtractElement(Op0, Op1);
    break;
  }
  case bitc::CST_CODE_CE_INSERTELT
      : { // CE_INSERTELT: [opval, opval, opty, opval]
    VectorType *OpTy = dyn_cast<VectorType>(CurTy);
    if (Record.size() < 3 || !OpTy)
      return error("Invalid record");
    Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
    Constant *Op1 = ValueList.getConstantFwdRef(Record[1],
                                                OpTy->getElementType());
    Constant *Op2 = nullptr;
    if (Record.size() == 4) {
      Type *IdxTy = getTypeByID(Record[2]);
      if (!IdxTy)
        return error("Invalid record");
      Op2 = ValueList.getConstantFwdRef(Record[3], IdxTy);
    } else {
      // Deprecated, but still needed to read old bitcode files.
      Op2 = ValueList.getConstantFwdRef(Record[2], Type::getInt32Ty(Context));
    }
    if (!Op2)
      return error("Invalid record");
    V = ConstantExpr::getInsertElement(Op0, Op1, Op2);
    break;
  }
  case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
    VectorType *OpTy = dyn_cast<VectorType>(CurTy);
    if (Record.size() < 3 || !OpTy)
      return error("Invalid record");
    DelayedShuffles.push_back(
        {OpTy, OpTy, Record[0], Record[1], Record[2], NextCstNo});
    ++NextCstNo;
    continue;
  }
  case bitc::CST_CODE_CE_SHUFVEC_EX: { // [opty, opval, opval, opval]
    VectorType *RTy = dyn_cast<VectorType>(CurTy);
    VectorType *OpTy =
      dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
    if (Record.size() < 4 || !RTy || !OpTy)
      return error("Invalid record");
    DelayedShuffles.push_back(
        {OpTy, RTy, Record[1], Record[2], Record[3], NextCstNo});
    ++NextCstNo;
    continue;
  }
  case bitc::CST_CODE_CE_CMP: {     // CE_CMP: [opty, opval, opval, pred]
    if (Record.size() < 4)
      return error("Invalid record");
    Type *OpTy = getTypeByID(Record[0]);
    if (!OpTy)
      return error("Invalid record");
    Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
    Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);

    if (OpTy->isFPOrFPVectorTy())
      V = ConstantExpr::getFCmp(Record[3], Op0, Op1);
    else
      V = ConstantExpr::getICmp(Record[3], Op0, Op1);
    break;
  }
  // This maintains backward compatibility, pre-asm dialect keywords.
  // Deprecated, but still needed to read old bitcode files.
  case bitc::CST_CODE_INLINEASM_OLD: {
    if (Record.size() < 2)
      return error("Invalid record");
    std::string AsmStr, ConstrStr;
    bool HasSideEffects = Record[0] & 1;
    bool IsAlignStack = Record[0] >> 1;
    unsigned AsmStrSize = Record[1];
    if (2+AsmStrSize >= Record.size())
      return error("Invalid record");
    unsigned ConstStrSize = Record[2+AsmStrSize];
    if (3+AsmStrSize+ConstStrSize > Record.size())
      return error("Invalid record");

    for (unsigned i = 0; i != AsmStrSize; ++i)
      AsmStr += (char)Record[2+i];
    for (unsigned i = 0; i != ConstStrSize; ++i)
      ConstrStr += (char)Record[3+AsmStrSize+i];
    UpgradeInlineAsmString(&AsmStr);
    // FIXME: support upgrading in opaque pointers mode.
    V = InlineAsm::get(cast<FunctionType>(CurTy->getPointerElementType()),
                       AsmStr, ConstrStr, HasSideEffects, IsAlignStack);
    break;
  }
  // This version adds support for the asm dialect keywords (e.g.,
  // inteldialect).
  case bitc::CST_CODE_INLINEASM_OLD2: {
    if (Record.size() < 2)
      return error("Invalid record");
    std::string AsmStr, ConstrStr;
    bool HasSideEffects = Record[0] & 1;
    bool IsAlignStack = (Record[0] >> 1) & 1;
    unsigned AsmDialect = Record[0] >> 2;
    unsigned AsmStrSize = Record[1];
    if (2+AsmStrSize >= Record.size())
      return error("Invalid record");
    unsigned ConstStrSize = Record[2+AsmStrSize];
    if (3+AsmStrSize+ConstStrSize > Record.size())
      return error("Invalid record");

    for (unsigned i = 0; i != AsmStrSize; ++i)
      AsmStr += (char)Record[2+i];
    for (unsigned i = 0; i != ConstStrSize; ++i)
      ConstrStr += (char)Record[3+AsmStrSize+i];
    UpgradeInlineAsmString(&AsmStr);
    // FIXME: support upgrading in opaque pointers mode.
    V = InlineAsm::get(cast<FunctionType>(CurTy->getPointerElementType()),
                       AsmStr, ConstrStr, HasSideEffects, IsAlignStack,
                       InlineAsm::AsmDialect(AsmDialect));
    break;
  }
  // This version adds support for the unwind keyword.
  case bitc::CST_CODE_INLINEASM_OLD3: {
    if (Record.size() < 2)
      return error("Invalid record");
    unsigned OpNum = 0;
    std::string AsmStr, ConstrStr;
    bool HasSideEffects = Record[OpNum] & 1;
    bool IsAlignStack = (Record[OpNum] >> 1) & 1;
    unsigned AsmDialect = (Record[OpNum] >> 2) & 1;
    bool CanThrow = (Record[OpNum] >> 3) & 1;
    ++OpNum;
    unsigned AsmStrSize = Record[OpNum];
    ++OpNum;
    if (OpNum + AsmStrSize >= Record.size())
      return error("Invalid record");
    unsigned ConstStrSize = Record[OpNum + AsmStrSize];
    if (OpNum + 1 + AsmStrSize + ConstStrSize > Record.size())
      return error("Invalid record");

    for (unsigned i = 0; i != AsmStrSize; ++i)
      AsmStr += (char)Record[OpNum + i];
    ++OpNum;
    for (unsigned i = 0; i != ConstStrSize; ++i)
      ConstrStr += (char)Record[OpNum + AsmStrSize + i];
    UpgradeInlineAsmString(&AsmStr);
    // FIXME: support upgrading in opaque pointers mode.
    V = InlineAsm::get(cast<FunctionType>(CurTy->getPointerElementType()),
                       AsmStr, ConstrStr, HasSideEffects, IsAlignStack,
                       InlineAsm::AsmDialect(AsmDialect), CanThrow);
    break;
  }
  // This version adds explicit function type.
  case bitc::CST_CODE_INLINEASM: {
    if (Record.size() < 3)
      return error("Invalid record");
    unsigned OpNum = 0;
    auto *FnTy = dyn_cast_or_null<FunctionType>(getTypeByID(Record[OpNum]));
    ++OpNum;
    if (!FnTy)
      return error("Invalid record");
    std::string AsmStr, ConstrStr;
    bool HasSideEffects = Record[OpNum] & 1;
    bool IsAlignStack = (Record[OpNum] >> 1) & 1;
    unsigned AsmDialect = (Record[OpNum] >> 2) & 1;
    bool CanThrow = (Record[OpNum] >> 3) & 1;
    ++OpNum;
    unsigned AsmStrSize = Record[OpNum];
    ++OpNum;
    if (OpNum + AsmStrSize >= Record.size())
      return error("Invalid record");
    unsigned ConstStrSize = Record[OpNum + AsmStrSize];
    if (OpNum + 1 + AsmStrSize + ConstStrSize > Record.size())
      return error("Invalid record");

    for (unsigned i = 0; i != AsmStrSize; ++i)
      AsmStr += (char)Record[OpNum + i];
    ++OpNum;
    for (unsigned i = 0; i != ConstStrSize; ++i)
      ConstrStr += (char)Record[OpNum + AsmStrSize + i];
    UpgradeInlineAsmString(&AsmStr);
    V = InlineAsm::get(FnTy, AsmStr, ConstrStr, HasSideEffects, IsAlignStack,
                       InlineAsm::AsmDialect(AsmDialect), CanThrow);
    break;
  }
  case bitc::CST_CODE_BLOCKADDRESS:{
    if (Record.size() < 3)
      return error("Invalid record");
    Type *FnTy = getTypeByID(Record[0]);
    if (!FnTy)
      return error("Invalid record");
    Function *Fn =
      dyn_cast_or_null<Function>(ValueList.getConstantFwdRef(Record[1],FnTy));
    if (!Fn)
      return error("Invalid record");

    // If the function is already parsed we can insert the block address right
    // away.
    BasicBlock *BB;
    unsigned BBID = Record[2];
    if (!BBID)
      // Invalid reference to entry block.
      return error("Invalid ID");
    if (!Fn->empty()) {
      Function::iterator BBI = Fn->begin(), BBE = Fn->end();
      for (size_t I = 0, E = BBID; I != E; ++I) {
        if (BBI == BBE)
          return error("Invalid ID");
        ++BBI;
      }
      BB = &*BBI;
    } else {
      // Otherwise insert a placeholder and remember it so it can be inserted
      // when the function is parsed.
      auto &FwdBBs = BasicBlockFwdRefs[Fn];
      if (FwdBBs.empty())
        BasicBlockFwdRefQueue.push_back(Fn);
      if (FwdBBs.size() < BBID + 1)
        FwdBBs.resize(BBID + 1);
      if (!FwdBBs[BBID])
        FwdBBs[BBID] = BasicBlock::Create(Context);
      BB = FwdBBs[BBID];
    }
    V = BlockAddress::get(Fn, BB);
    break;
  }
  case bitc::CST_CODE_DSO_LOCAL_EQUIVALENT: {
    if (Record.size() < 2)
      return error("Invalid record");
    Type *GVTy = getTypeByID(Record[0]);
    if (!GVTy)
      return error("Invalid record");
    GlobalValue *GV = dyn_cast_or_null<GlobalValue>(
        ValueList.getConstantFwdRef(Record[1], GVTy));
    if (!GV)
      return error("Invalid record");

    V = DSOLocalEquivalent::get(GV);
    break;
  }
  case bitc::CST_CODE_NO_CFI_VALUE: {
    if (Record.size() < 2)
      return error("Invalid record");
    Type *GVTy = getTypeByID(Record[0]);
    if (!GVTy)
      return error("Invalid record");
    GlobalValue *GV = dyn_cast_or_null<GlobalValue>(
        ValueList.getConstantFwdRef(Record[1], GVTy));
    if (!GV)
      return error("Invalid record");
    V = NoCFIValue::get(GV);
    break;
  }
  }

  ValueList.assignValue(V, NextCstNo);
  ++NextCstNo;
}
3001}

3003Error BitcodeReader::parseUseLists() {
if (Error Err = Stream.EnterSubBlock(bitc::USELIST_BLOCK_ID))
  return Err;

// Read all the records.
SmallVector<uint64_t, 64> Record;

while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return Error::success();
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Read a use list record.
  Record.clear();
  bool IsBB = false;
  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  switch (MaybeRecord.get()) {
  default:  // Default behavior: unknown type.
    break;
  case bitc::USELIST_CODE_BB:
    IsBB = true;
    LLVM_FALLTHROUGH[[gnu::fallthrough]];
  case bitc::USELIST_CODE_DEFAULT: {
    unsigned RecordLength = Record.size();
    if (RecordLength < 3)
      // Records should have at least an ID and two indexes.
      return error("Invalid record");
    unsigned ID = Record.pop_back_val();

    Value *V;
    if (IsBB) {
      assert(ID < FunctionBBs.size() && "Basic block not found")(static_cast <bool> (ID < FunctionBBs.size() &&
 "Basic block not found") ? void (0) : __assert_fail ("ID < FunctionBBs.size() && \"Basic block not found\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 3048, __extension__
 __PRETTY_FUNCTION__));
      V = FunctionBBs[ID];
    } else
      V = ValueList[ID];
    unsigned NumUses = 0;
    SmallDenseMap<const Use *, unsigned, 16> Order;
    for (const Use &U : V->materialized_uses()) {
      if (++NumUses > Record.size())
        break;
      Order[&U] = Record[NumUses - 1];
    }
    if (Order.size() != Record.size() || NumUses > Record.size())
      // Mismatches can happen if the functions are being materialized lazily
      // (out-of-order), or a value has been upgraded.
      break;

    V->sortUseList([&](const Use &L, const Use &R) {
      return Order.lookup(&L) < Order.lookup(&R);
    });
    break;
  }
  }
}
3071}

3073/// When we see the block for metadata, remember where it is and then skip it.
3074/// This lets us lazily deserialize the metadata.
3075Error BitcodeReader::rememberAndSkipMetadata() {
// Save the current stream state.
uint64_t CurBit = Stream.GetCurrentBitNo();
DeferredMetadataInfo.push_back(CurBit);

// Skip over the block for now.
if (Error Err = Stream.SkipBlock())
  return Err;
return Error::success();
3084}

3086Error BitcodeReader::materializeMetadata() {
for (uint64_t BitPos : DeferredMetadataInfo) {
  // Move the bit stream to the saved position.
  if (Error JumpFailed = Stream.JumpToBit(BitPos))
    return JumpFailed;
  if (Error Err = MDLoader->parseModuleMetadata())
    return Err;
}

// Upgrade "Linker Options" module flag to "llvm.linker.options" module-level
// metadata. Only upgrade if the new option doesn't exist to avoid upgrade
// multiple times.
if (!TheModule->getNamedMetadata("llvm.linker.options")) {
  if (Metadata *Val = TheModule->getModuleFlag("Linker Options")) {
    NamedMDNode *LinkerOpts =
        TheModule->getOrInsertNamedMetadata("llvm.linker.options");
    for (const MDOperand &MDOptions : cast<MDNode>(Val)->operands())
      LinkerOpts->addOperand(cast<MDNode>(MDOptions));
  }
}

DeferredMetadataInfo.clear();
return Error::success();
3109}

3111void BitcodeReader::setStripDebugInfo() { StripDebugInfo = true; }

3113/// When we see the block for a function body, remember where it is and then
3114/// skip it.  This lets us lazily deserialize the functions.
3115Error BitcodeReader::rememberAndSkipFunctionBody() {
// Get the function we are talking about.
if (FunctionsWithBodies.empty())
  return error("Insufficient function protos");

Function *Fn = FunctionsWithBodies.back();
FunctionsWithBodies.pop_back();

// Save the current stream state.
uint64_t CurBit = Stream.GetCurrentBitNo();
assert((static_cast <bool> ((DeferredFunctionInfo[Fn] == 0 || DeferredFunctionInfo
[Fn] == CurBit) && "Mismatch between VST and scanned function offsets"
) ? void (0) : __assert_fail ("(DeferredFunctionInfo[Fn] == 0 || DeferredFunctionInfo[Fn] == CurBit) && \"Mismatch between VST and scanned function offsets\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 3127, __extension__
 __PRETTY_FUNCTION__))
    (DeferredFunctionInfo[Fn] == 0 || DeferredFunctionInfo[Fn] == CurBit) &&(static_cast <bool> ((DeferredFunctionInfo[Fn] == 0 || DeferredFunctionInfo
[Fn] == CurBit) && "Mismatch between VST and scanned function offsets"
) ? void (0) : __assert_fail ("(DeferredFunctionInfo[Fn] == 0 || DeferredFunctionInfo[Fn] == CurBit) && \"Mismatch between VST and scanned function offsets\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 3127, __extension__
 __PRETTY_FUNCTION__))
    "Mismatch between VST and scanned function offsets")(static_cast <bool> ((DeferredFunctionInfo[Fn] == 0 || DeferredFunctionInfo
[Fn] == CurBit) && "Mismatch between VST and scanned function offsets"
) ? void (0) : __assert_fail ("(DeferredFunctionInfo[Fn] == 0 || DeferredFunctionInfo[Fn] == CurBit) && \"Mismatch between VST and scanned function offsets\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 3127, __extension__
 __PRETTY_FUNCTION__));
DeferredFunctionInfo[Fn] = CurBit;

// Skip over the function block for now.
if (Error Err = Stream.SkipBlock())
  return Err;
return Error::success();
3134}

3136Error BitcodeReader::globalCleanup() {
// Patch the initializers for globals and aliases up.
if (Error Err = resolveGlobalAndIndirectSymbolInits())
  return Err;
if (!GlobalInits.empty() || !IndirectSymbolInits.empty())
  return error("Malformed global initializer set");

// Look for intrinsic functions which need to be upgraded at some point
// and functions that need to have their function attributes upgraded.
for (Function &F : *TheModule) {
  MDLoader->upgradeDebugIntrinsics(F);
  Function *NewFn;
  if (UpgradeIntrinsicFunction(&F, NewFn))
    UpgradedIntrinsics[&F] = NewFn;
  else if (auto Remangled = Intrinsic::remangleIntrinsicFunction(&F))
    // Some types could be renamed during loading if several modules are
    // loaded in the same LLVMContext (LTO scenario). In this case we should
    // remangle intrinsics names as well.
    RemangledIntrinsics[&F] = Remangled.getValue();
  // Look for functions that rely on old function attribute behavior.
  UpgradeFunctionAttributes(F);
}

// Look for global variables which need to be renamed.
std::vector<std::pair<GlobalVariable *, GlobalVariable *>> UpgradedVariables;
for (GlobalVariable &GV : TheModule->globals())
  if (GlobalVariable *Upgraded = UpgradeGlobalVariable(&GV))
    UpgradedVariables.emplace_back(&GV, Upgraded);
for (auto &Pair : UpgradedVariables) {
  Pair.first->eraseFromParent();
  TheModule->getGlobalList().push_back(Pair.second);
}

// Force deallocation of memory for these vectors to favor the client that
// want lazy deserialization.
std::vector<std::pair<GlobalVariable *, unsigned>>().swap(GlobalInits);
std::vector<std::pair<GlobalValue *, unsigned>>().swap(IndirectSymbolInits);
return Error::success();
3174}

3176/// Support for lazy parsing of function bodies. This is required if we
3177/// either have an old bitcode file without a VST forward declaration record,
3178/// or if we have an anonymous function being materialized, since anonymous
3179/// functions do not have a name and are therefore not in the VST.
3180Error BitcodeReader::rememberAndSkipFunctionBodies() {
if (Error JumpFailed = Stream.JumpToBit(NextUnreadBit))
  return JumpFailed;

if (Stream.AtEndOfStream())
  return error("Could not find function in stream");

if (!SeenFirstFunctionBody)
  return error("Trying to materialize functions before seeing function blocks");

// An old bitcode file with the symbol table at the end would have
// finished the parse greedily.
assert(SeenValueSymbolTable)(static_cast <bool> (SeenValueSymbolTable) ? void (0) :
 __assert_fail ("SeenValueSymbolTable", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 3192, __extension__ __PRETTY_FUNCTION__));

SmallVector<uint64_t, 64> Record;

while (true) {
  Expected<llvm::BitstreamEntry> MaybeEntry = Stream.advance();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  llvm::BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  default:
    return error("Expect SubBlock");
  case BitstreamEntry::SubBlock:
    switch (Entry.ID) {
    default:
      return error("Expect function block");
    case bitc::FUNCTION_BLOCK_ID:
      if (Error Err = rememberAndSkipFunctionBody())
        return Err;
      NextUnreadBit = Stream.GetCurrentBitNo();
      return Error::success();
    }
  }
}
3217}

3219Error BitcodeReaderBase::readBlockInfo() {
Expected<Optional<BitstreamBlockInfo>> MaybeNewBlockInfo =
    Stream.ReadBlockInfoBlock();
if (!MaybeNewBlockInfo)
  return MaybeNewBlockInfo.takeError();
Optional<BitstreamBlockInfo> NewBlockInfo =
    std::move(MaybeNewBlockInfo.get());
if (!NewBlockInfo)
  return error("Malformed block");
BlockInfo = std::move(*NewBlockInfo);
return Error::success();
3230}

3232Error BitcodeReader::parseComdatRecord(ArrayRef<uint64_t> Record) {
// v1: [selection_kind, name]
// v2: [strtab_offset, strtab_size, selection_kind]
StringRef Name;
std::tie(Name, Record) = readNameFromStrtab(Record);

if (Record.empty())
  return error("Invalid record");
Comdat::SelectionKind SK = getDecodedComdatSelectionKind(Record[0]);
std::string OldFormatName;
if (!UseStrtab) {
  if (Record.size() < 2)
    return error("Invalid record");
  unsigned ComdatNameSize = Record[1];
  if (ComdatNameSize > Record.size() - 2)
    return error("Comdat name size too large");
  OldFormatName.reserve(ComdatNameSize);
  for (unsigned i = 0; i != ComdatNameSize; ++i)
    OldFormatName += (char)Record[2 + i];
  Name = OldFormatName;
}
Comdat *C = TheModule->getOrInsertComdat(Name);
C->setSelectionKind(SK);
ComdatList.push_back(C);
return Error::success();
3257}

3259static void inferDSOLocal(GlobalValue *GV) {
// infer dso_local from linkage and visibility if it is not encoded.
if (GV->hasLocalLinkage() ||
    (!GV->hasDefaultVisibility() && !GV->hasExternalWeakLinkage()))
  GV->setDSOLocal(true);
3264}

3266Error BitcodeReader::parseGlobalVarRecord(ArrayRef<uint64_t> Record) {
// v1: [pointer type, isconst, initid, linkage, alignment, section,
// visibility, threadlocal, unnamed_addr, externally_initialized,
// dllstorageclass, comdat, attributes, preemption specifier,
// partition strtab offset, partition strtab size] (name in VST)
// v2: [strtab_offset, strtab_size, v1]
StringRef Name;
std::tie(Name, Record) = readNameFromStrtab(Record);

if (Record.size() < 6)
  return error("Invalid record");
Type *Ty = getTypeByID(Record[0]);
if (!Ty)
  return error("Invalid record");
bool isConstant = Record[1] & 1;
bool explicitType = Record[1] & 2;
unsigned AddressSpace;
if (explicitType) {
  AddressSpace = Record[1] >> 2;
} else {
  if (!Ty->isPointerTy())
    return error("Invalid type for value");
  AddressSpace = cast<PointerType>(Ty)->getAddressSpace();
  Ty = Ty->getPointerElementType();
}

uint64_t RawLinkage = Record[3];
GlobalValue::LinkageTypes Linkage = getDecodedLinkage(RawLinkage);
MaybeAlign Alignment;
if (Error Err = parseAlignmentValue(Record[4], Alignment))
  return Err;
std::string Section;
if (Record[5]) {
  if (Record[5] - 1 >= SectionTable.size())
    return error("Invalid ID");
  Section = SectionTable[Record[5] - 1];
}
GlobalValue::VisibilityTypes Visibility = GlobalValue::DefaultVisibility;
// Local linkage must have default visibility.
// auto-upgrade `hidden` and `protected` for old bitcode.
if (Record.size() > 6 && !GlobalValue::isLocalLinkage(Linkage))
  Visibility = getDecodedVisibility(Record[6]);

GlobalVariable::ThreadLocalMode TLM = GlobalVariable::NotThreadLocal;
if (Record.size() > 7)
  TLM = getDecodedThreadLocalMode(Record[7]);

GlobalValue::UnnamedAddr UnnamedAddr = GlobalValue::UnnamedAddr::None;
if (Record.size() > 8)
  UnnamedAddr = getDecodedUnnamedAddrType(Record[8]);

bool ExternallyInitialized = false;
if (Record.size() > 9)
  ExternallyInitialized = Record[9];

GlobalVariable *NewGV =
    new GlobalVariable(*TheModule, Ty, isConstant, Linkage, nullptr, Name,
                       nullptr, TLM, AddressSpace, ExternallyInitialized);
NewGV->setAlignment(Alignment);
if (!Section.empty())
  NewGV->setSection(Section);
NewGV->setVisibility(Visibility);
NewGV->setUnnamedAddr(UnnamedAddr);

if (Record.size() > 10)
  NewGV->setDLLStorageClass(getDecodedDLLStorageClass(Record[10]));
else
  upgradeDLLImportExportLinkage(NewGV, RawLinkage);

ValueList.push_back(NewGV);

// Remember which value to use for the global initializer.
if (unsigned InitID = Record[2])
  GlobalInits.push_back(std::make_pair(NewGV, InitID - 1));

if (Record.size() > 11) {
  if (unsigned ComdatID = Record[11]) {
    if (ComdatID > ComdatList.size())
      return error("Invalid global variable comdat ID");
    NewGV->setComdat(ComdatList[ComdatID - 1]);
  }
} else if (hasImplicitComdat(RawLinkage)) {
  ImplicitComdatObjects.insert(NewGV);
}

if (Record.size() > 12) {
  auto AS = getAttributes(Record[12]).getFnAttrs();
  NewGV->setAttributes(AS);
}

if (Record.size() > 13) {
  NewGV->setDSOLocal(getDecodedDSOLocal(Record[13]));
}
inferDSOLocal(NewGV);

// Check whether we have enough values to read a partition name.
if (Record.size() > 15)
  NewGV->setPartition(StringRef(Strtab.data() + Record[14], Record[15]));

return Error::success();
3366}

3368Error BitcodeReader::parseFunctionRecord(ArrayRef<uint64_t> Record) {
// v1: [type, callingconv, isproto, linkage, paramattr, alignment, section,
// visibility, gc, unnamed_addr, prologuedata, dllstorageclass, comdat,
// prefixdata,  personalityfn, preemption specifier, addrspace] (name in VST)
// v2: [strtab_offset, strtab_size, v1]
StringRef Name;
std::tie(Name, Record) = readNameFromStrtab(Record);

if (Record.size() < 8)
  return error("Invalid record");
Type *FTy = getTypeByID(Record[0]);
if (!FTy)
  return error("Invalid record");
if (auto *PTy = dyn_cast<PointerType>(FTy))
  FTy = PTy->getPointerElementType();

if (!isa<FunctionType>(FTy))
  return error("Invalid type for value");
auto CC = static_cast<CallingConv::ID>(Record[1]);
if (CC & ~CallingConv::MaxID)
  return error("Invalid calling convention ID");

unsigned AddrSpace = TheModule->getDataLayout().getProgramAddressSpace();
if (Record.size() > 16)
  AddrSpace = Record[16];

Function *Func =
    Function::Create(cast<FunctionType>(FTy), GlobalValue::ExternalLinkage,
                     AddrSpace, Name, TheModule);

assert(Func->getFunctionType() == FTy &&(static_cast <bool> (Func->getFunctionType() == FTy &&
 "Incorrect fully specified type provided for function") ? void
 (0) : __assert_fail ("Func->getFunctionType() == FTy && \"Incorrect fully specified type provided for function\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 3399, __extension__
 __PRETTY_FUNCTION__))
       "Incorrect fully specified type provided for function")(static_cast <bool> (Func->getFunctionType() == FTy &&
 "Incorrect fully specified type provided for function") ? void
 (0) : __assert_fail ("Func->getFunctionType() == FTy && \"Incorrect fully specified type provided for function\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 3399, __extension__
 __PRETTY_FUNCTION__));
FunctionTypes[Func] = cast<FunctionType>(FTy);

Func->setCallingConv(CC);
bool isProto = Record[2];
uint64_t RawLinkage = Record[3];
Func->setLinkage(getDecodedLinkage(RawLinkage));
Func->setAttributes(getAttributes(Record[4]));

// Upgrade any old-style byval or sret without a type by propagating the
// argument's pointee type. There should be no opaque pointers where the byval
// type is implicit.
for (unsigned i = 0; i != Func->arg_size(); ++i) {
  for (Attribute::AttrKind Kind : {Attribute::ByVal, Attribute::StructRet,
                                   Attribute::InAlloca}) {
    if (!Func->hasParamAttribute(i, Kind))
      continue;

    if (Func->getParamAttribute(i, Kind).getValueAsType())
      continue;

    Func->removeParamAttr(i, Kind);

    Type *PTy = cast<FunctionType>(FTy)->getParamType(i);
    Type *PtrEltTy = PTy->getPointerElementType();
    Attribute NewAttr;
    switch (Kind) {
    case Attribute::ByVal:
      NewAttr = Attribute::getWithByValType(Context, PtrEltTy);
      break;
    case Attribute::StructRet:
      NewAttr = Attribute::getWithStructRetType(Context, PtrEltTy);
      break;
    case Attribute::InAlloca:
      NewAttr = Attribute::getWithInAllocaType(Context, PtrEltTy);
      break;
    default:
      llvm_unreachable("not an upgraded type attribute")::llvm::llvm_unreachable_internal("not an upgraded type attribute"
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 3436);
    }

    Func->addParamAttr(i, NewAttr);
  }
}

MaybeAlign Alignment;
if (Error Err = parseAlignmentValue(Record[5], Alignment))
  return Err;
Func->setAlignment(Alignment);
if (Record[6]) {
  if (Record[6] - 1 >= SectionTable.size())
    return error("Invalid ID");
  Func->setSection(SectionTable[Record[6] - 1]);
}
// Local linkage must have default visibility.
// auto-upgrade `hidden` and `protected` for old bitcode.
if (!Func->hasLocalLinkage())
  Func->setVisibility(getDecodedVisibility(Record[7]));
if (Record.size() > 8 && Record[8]) {
  if (Record[8] - 1 >= GCTable.size())
    return error("Invalid ID");
  Func->setGC(GCTable[Record[8] - 1]);
}
GlobalValue::UnnamedAddr UnnamedAddr = GlobalValue::UnnamedAddr::None;
if (Record.size() > 9)
  UnnamedAddr = getDecodedUnnamedAddrType(Record[9]);
Func->setUnnamedAddr(UnnamedAddr);

FunctionOperandInfo OperandInfo = {Func, 0, 0, 0};
if (Record.size() > 10)
  OperandInfo.Prologue = Record[10];

if (Record.size() > 11)
  Func->setDLLStorageClass(getDecodedDLLStorageClass(Record[11]));
else
  upgradeDLLImportExportLinkage(Func, RawLinkage);

if (Record.size() > 12) {
  if (unsigned ComdatID = Record[12]) {
    if (ComdatID > ComdatList.size())
      return error("Invalid function comdat ID");
    Func->setComdat(ComdatList[ComdatID - 1]);
  }
} else if (hasImplicitComdat(RawLinkage)) {
  ImplicitComdatObjects.insert(Func);
}

if (Record.size() > 13)
  OperandInfo.Prefix = Record[13];

if (Record.size() > 14)
  OperandInfo.PersonalityFn = Record[14];

if (Record.size() > 15) {
  Func->setDSOLocal(getDecodedDSOLocal(Record[15]));
}
inferDSOLocal(Func);

// Record[16] is the address space number.

// Check whether we have enough values to read a partition name. Also make
// sure Strtab has enough values.
if (Record.size() > 18 && Strtab.data() &&
    Record[17] + Record[18] <= Strtab.size()) {
  Func->setPartition(StringRef(Strtab.data() + Record[17], Record[18]));
}

ValueList.push_back(Func);

if (OperandInfo.PersonalityFn || OperandInfo.Prefix || OperandInfo.Prologue)
  FunctionOperands.push_back(OperandInfo);

// If this is a function with a body, remember the prototype we are
// creating now, so that we can match up the body with them later.
if (!isProto) {
  Func->setIsMaterializable(true);
  FunctionsWithBodies.push_back(Func);
  DeferredFunctionInfo[Func] = 0;
}
return Error::success();
3518}

3520Error BitcodeReader::parseGlobalIndirectSymbolRecord(
  unsigned BitCode, ArrayRef<uint64_t> Record) {
// v1 ALIAS_OLD: [alias type, aliasee val#, linkage] (name in VST)
// v1 ALIAS: [alias type, addrspace, aliasee val#, linkage, visibility,
// dllstorageclass, threadlocal, unnamed_addr,
// preemption specifier] (name in VST)
// v1 IFUNC: [alias type, addrspace, aliasee val#, linkage,
// visibility, dllstorageclass, threadlocal, unnamed_addr,
// preemption specifier] (name in VST)
// v2: [strtab_offset, strtab_size, v1]
StringRef Name;
std::tie(Name, Record) = readNameFromStrtab(Record);

bool NewRecord = BitCode != bitc::MODULE_CODE_ALIAS_OLD;
if (Record.size() < (3 + (unsigned)NewRecord))
  return error("Invalid record");
unsigned OpNum = 0;
Type *Ty = getTypeByID(Record[OpNum++]);
if (!Ty)
  return error("Invalid record");

unsigned AddrSpace;
if (!NewRecord) {
  auto *PTy = dyn_cast<PointerType>(Ty);
  if (!PTy)
    return error("Invalid type for value");
  Ty = PTy->getPointerElementType();
  AddrSpace = PTy->getAddressSpace();
} else {
  AddrSpace = Record[OpNum++];
}

auto Val = Record[OpNum++];
auto Linkage = Record[OpNum++];
GlobalValue *NewGA;
if (BitCode == bitc::MODULE_CODE_ALIAS ||
    BitCode == bitc::MODULE_CODE_ALIAS_OLD)
  NewGA = GlobalAlias::create(Ty, AddrSpace, getDecodedLinkage(Linkage), Name,
                              TheModule);
else
  NewGA = GlobalIFunc::create(Ty, AddrSpace, getDecodedLinkage(Linkage), Name,
                              nullptr, TheModule);

// Local linkage must have default visibility.
// auto-upgrade `hidden` and `protected` for old bitcode.
if (OpNum != Record.size()) {
  auto VisInd = OpNum++;
  if (!NewGA->hasLocalLinkage())
    NewGA->setVisibility(getDecodedVisibility(Record[VisInd]));
}
if (BitCode == bitc::MODULE_CODE_ALIAS ||
    BitCode == bitc::MODULE_CODE_ALIAS_OLD) {
  if (OpNum != Record.size())
    NewGA->setDLLStorageClass(getDecodedDLLStorageClass(Record[OpNum++]));
  else
    upgradeDLLImportExportLinkage(NewGA, Linkage);
  if (OpNum != Record.size())
    NewGA->setThreadLocalMode(getDecodedThreadLocalMode(Record[OpNum++]));
  if (OpNum != Record.size())
    NewGA->setUnnamedAddr(getDecodedUnnamedAddrType(Record[OpNum++]));
}
if (OpNum != Record.size())
  NewGA->setDSOLocal(getDecodedDSOLocal(Record[OpNum++]));
inferDSOLocal(NewGA);

// Check whether we have enough values to read a partition name.
if (OpNum + 1 < Record.size()) {
  NewGA->setPartition(
      StringRef(Strtab.data() + Record[OpNum], Record[OpNum + 1]));
  OpNum += 2;
}

ValueList.push_back(NewGA);
IndirectSymbolInits.push_back(std::make_pair(NewGA, Val));
return Error::success();
3595}

3597Error BitcodeReader::parseModule(uint64_t ResumeBit,
                               bool ShouldLazyLoadMetadata,
                               DataLayoutCallbackTy DataLayoutCallback) {
if (ResumeBit) {
  if (Error JumpFailed = Stream.JumpToBit(ResumeBit))
    return JumpFailed;
} else if (Error Err = Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
  return Err;

SmallVector<uint64_t, 64> Record;

// Parts of bitcode parsing depend on the datalayout.  Make sure we
// finalize the datalayout before we run any of that code.
bool ResolvedDataLayout = false;
auto ResolveDataLayout = [&] {
  if (ResolvedDataLayout)
    return;

  // datalayout and triple can't be parsed after this point.
  ResolvedDataLayout = true;

  // Upgrade data layout string.
  std::string DL = llvm::UpgradeDataLayoutString(
      TheModule->getDataLayoutStr(), TheModule->getTargetTriple());
  TheModule->setDataLayout(DL);

  if (auto LayoutOverride =
          DataLayoutCallback(TheModule->getTargetTriple()))
    TheModule->setDataLayout(*LayoutOverride);
};

// Read all the records for this module.
while (true) {
  Expected<llvm::BitstreamEntry> MaybeEntry = Stream.advance();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  llvm::BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    ResolveDataLayout();
    return globalCleanup();

  case BitstreamEntry::SubBlock:
    switch (Entry.ID) {
    default:  // Skip unknown content.
      if (Error Err = Stream.SkipBlock())
        return Err;
      break;
    case bitc::BLOCKINFO_BLOCK_ID:
      if (Error Err = readBlockInfo())
        return Err;
      break;
    case bitc::PARAMATTR_BLOCK_ID:
      if (Error Err = parseAttributeBlock())
        return Err;
      break;
    case bitc::PARAMATTR_GROUP_BLOCK_ID:
      if (Error Err = parseAttributeGroupBlock())
        return Err;
      break;
    case bitc::TYPE_BLOCK_ID_NEW:
      if (Error Err = parseTypeTable())
        return Err;
      break;
    case bitc::VALUE_SYMTAB_BLOCK_ID:
      if (!SeenValueSymbolTable) {
        // Either this is an old form VST without function index and an
        // associated VST forward declaration record (which would have caused
        // the VST to be jumped to and parsed before it was encountered
        // normally in the stream), or there were no function blocks to
        // trigger an earlier parsing of the VST.
        assert(VSTOffset == 0 || FunctionsWithBodies.empty())(static_cast <bool> (VSTOffset == 0 || FunctionsWithBodies
.empty()) ? void (0) : __assert_fail ("VSTOffset == 0 || FunctionsWithBodies.empty()"
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 3671, __extension__
 __PRETTY_FUNCTION__));
        if (Error Err = parseValueSymbolTable())
          return Err;
        SeenValueSymbolTable = true;
      } else {
        // We must have had a VST forward declaration record, which caused
        // the parser to jump to and parse the VST earlier.
        assert(VSTOffset > 0)(static_cast <bool> (VSTOffset > 0) ? void (0) : __assert_fail
 ("VSTOffset > 0", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 3678, __extension__ __PRETTY_FUNCTION__));
        if (Error Err = Stream.SkipBlock())
          return Err;
      }
      break;
    case bitc::CONSTANTS_BLOCK_ID:
      if (Error Err = parseConstants())
        return Err;
      if (Error Err = resolveGlobalAndIndirectSymbolInits())
        return Err;
      break;
    case bitc::METADATA_BLOCK_ID:
      if (ShouldLazyLoadMetadata) {
        if (Error Err = rememberAndSkipMetadata())
          return Err;
        break;
      }
      assert(DeferredMetadataInfo.empty() && "Unexpected deferred metadata")(static_cast <bool> (DeferredMetadataInfo.empty() &&
 "Unexpected deferred metadata") ? void (0) : __assert_fail (
"DeferredMetadataInfo.empty() && \"Unexpected deferred metadata\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 3695, __extension__
 __PRETTY_FUNCTION__));
      if (Error Err = MDLoader->parseModuleMetadata())
        return Err;
      break;
    case bitc::METADATA_KIND_BLOCK_ID:
      if (Error Err = MDLoader->parseMetadataKinds())
        return Err;
      break;
    case bitc::FUNCTION_BLOCK_ID:
      ResolveDataLayout();

      // If this is the first function body we've seen, reverse the
      // FunctionsWithBodies list.
      if (!SeenFirstFunctionBody) {
        std::reverse(FunctionsWithBodies.begin(), FunctionsWithBodies.end());
        if (Error Err = globalCleanup())
          return Err;
        SeenFirstFunctionBody = true;
      }

      if (VSTOffset > 0) {
        // If we have a VST forward declaration record, make sure we
        // parse the VST now if we haven't already. It is needed to
        // set up the DeferredFunctionInfo vector for lazy reading.
        if (!SeenValueSymbolTable) {
          if (Error Err = BitcodeReader::parseValueSymbolTable(VSTOffset))
            return Err;
          SeenValueSymbolTable = true;
          // Fall through so that we record the NextUnreadBit below.
          // This is necessary in case we have an anonymous function that
          // is later materialized. Since it will not have a VST entry we
          // need to fall back to the lazy parse to find its offset.
        } else {
          // If we have a VST forward declaration record, but have already
          // parsed the VST (just above, when the first function body was
          // encountered here), then we are resuming the parse after
          // materializing functions. The ResumeBit points to the
          // start of the last function block recorded in the
          // DeferredFunctionInfo map. Skip it.
          if (Error Err = Stream.SkipBlock())
            return Err;
          continue;
        }
      }

      // Support older bitcode files that did not have the function
      // index in the VST, nor a VST forward declaration record, as
      // well as anonymous functions that do not have VST entries.
      // Build the DeferredFunctionInfo vector on the fly.
      if (Error Err = rememberAndSkipFunctionBody())
        return Err;

      // Suspend parsing when we reach the function bodies. Subsequent
      // materialization calls will resume it when necessary. If the bitcode
      // file is old, the symbol table will be at the end instead and will not
      // have been seen yet. In this case, just finish the parse now.
      if (SeenValueSymbolTable) {
        NextUnreadBit = Stream.GetCurrentBitNo();
        // After the VST has been parsed, we need to make sure intrinsic name
        // are auto-upgraded.
        return globalCleanup();
      }
      break;
    case bitc::USELIST_BLOCK_ID:
      if (Error Err = parseUseLists())
        return Err;
      break;
    case bitc::OPERAND_BUNDLE_TAGS_BLOCK_ID:
      if (Error Err = parseOperandBundleTags())
        return Err;
      break;
    case bitc::SYNC_SCOPE_NAMES_BLOCK_ID:
      if (Error Err = parseSyncScopeNames())
        return Err;
      break;
    }
    continue;

  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Read a record.
  Expected<unsigned> MaybeBitCode = Stream.readRecord(Entry.ID, Record);
  if (!MaybeBitCode)
    return MaybeBitCode.takeError();
  switch (unsigned BitCode = MaybeBitCode.get()) {
  default: break;  // Default behavior, ignore unknown content.
  case bitc::MODULE_CODE_VERSION: {
    Expected<unsigned> VersionOrErr = parseVersionRecord(Record);
    if (!VersionOrErr)
      return VersionOrErr.takeError();
    UseRelativeIDs = *VersionOrErr >= 1;
    break;
  }
  case bitc::MODULE_CODE_TRIPLE: {  // TRIPLE: [strchr x N]
    if (ResolvedDataLayout)
      return error("target triple too late in module");
    std::string S;
    if (convertToString(Record, 0, S))
      return error("Invalid record");
    TheModule->setTargetTriple(S);
    break;
  }
  case bitc::MODULE_CODE_DATALAYOUT: {  // DATALAYOUT: [strchr x N]
    if (ResolvedDataLayout)
      return error("datalayout too late in module");
    std::string S;
    if (convertToString(Record, 0, S))
      return error("Invalid record");
    Expected<DataLayout> MaybeDL = DataLayout::parse(S);
    if (!MaybeDL)
      return MaybeDL.takeError();
    TheModule->setDataLayout(MaybeDL.get());
    break;
  }
  case bitc::MODULE_CODE_ASM: {  // ASM: [strchr x N]
    std::string S;
    if (convertToString(Record, 0, S))
      return error("Invalid record");
    TheModule->setModuleInlineAsm(S);
    break;
  }
  case bitc::MODULE_CODE_DEPLIB: {  // DEPLIB: [strchr x N]
    // Deprecated, but still needed to read old bitcode files.
    std::string S;
    if (convertToString(Record, 0, S))
      return error("Invalid record");
    // Ignore value.
    break;
  }
  case bitc::MODULE_CODE_SECTIONNAME: {  // SECTIONNAME: [strchr x N]
    std::string S;
    if (convertToString(Record, 0, S))
      return error("Invalid record");
    SectionTable.push_back(S);
    break;
  }
  case bitc::MODULE_CODE_GCNAME: {  // SECTIONNAME: [strchr x N]
    std::string S;
    if (convertToString(Record, 0, S))
      return error("Invalid record");
    GCTable.push_back(S);
    break;
  }
  case bitc::MODULE_CODE_COMDAT:
    if (Error Err = parseComdatRecord(Record))
      return Err;
    break;
  // FIXME: BitcodeReader should handle {GLOBALVAR, FUNCTION, ALIAS, IFUNC}
  // written by ThinLinkBitcodeWriter. See
  // `ThinLinkBitcodeWriter::writeSimplifiedModuleInfo` for the format of each
  // record
  // (https://github.com/llvm/llvm-project/blob/b6a93967d9c11e79802b5e75cec1584d6c8aa472/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp#L4714)
  case bitc::MODULE_CODE_GLOBALVAR:
    if (Error Err = parseGlobalVarRecord(Record))
      return Err;
    break;
  case bitc::MODULE_CODE_FUNCTION:
    ResolveDataLayout();
    if (Error Err = parseFunctionRecord(Record))
      return Err;
    break;
  case bitc::MODULE_CODE_IFUNC:
  case bitc::MODULE_CODE_ALIAS:
  case bitc::MODULE_CODE_ALIAS_OLD:
    if (Error Err = parseGlobalIndirectSymbolRecord(BitCode, Record))
      return Err;
    break;
  /// MODULE_CODE_VSTOFFSET: [offset]
  case bitc::MODULE_CODE_VSTOFFSET:
    if (Record.empty())
      return error("Invalid record");
    // Note that we subtract 1 here because the offset is relative to one word
    // before the start of the identification or module block, which was
    // historically always the start of the regular bitcode header.
    VSTOffset = Record[0] - 1;
    break;
  /// MODULE_CODE_SOURCE_FILENAME: [namechar x N]
  case bitc::MODULE_CODE_SOURCE_FILENAME:
    SmallString<128> ValueName;
    if (convertToString(Record, 0, ValueName))
      return error("Invalid record");
    TheModule->setSourceFileName(ValueName);
    break;
  }
  Record.clear();
}
3884}

3886Error BitcodeReader::parseBitcodeInto(Module *M, bool ShouldLazyLoadMetadata,
                                    bool IsImporting,
                                    DataLayoutCallbackTy DataLayoutCallback) {
TheModule = M;
MDLoader = MetadataLoader(Stream, *M, ValueList, IsImporting,
                          [&](unsigned ID) { return getTypeByID(ID); });
return parseModule(0, ShouldLazyLoadMetadata, DataLayoutCallback);
3893}

3895Error BitcodeReader::typeCheckLoadStoreInst(Type *ValType, Type *PtrType) {
if (!isa<PointerType>(PtrType))
  return error("Load/Store operand is not a pointer type");

if (!cast<PointerType>(PtrType)->isOpaqueOrPointeeTypeMatches(ValType))
  return error("Explicit load/store type does not match pointee "
               "type of pointer operand");
if (!PointerType::isLoadableOrStorableType(ValType))
  return error("Cannot load/store from pointer");
return Error::success();
3905}

3907void BitcodeReader::propagateAttributeTypes(CallBase *CB,
                                          ArrayRef<Type *> ArgsTys) {
for (unsigned i = 0; i != CB->arg_size(); ++i) {
  for (Attribute::AttrKind Kind : {Attribute::ByVal, Attribute::StructRet,
                                   Attribute::InAlloca}) {
    if (!CB->paramHasAttr(i, Kind) ||
        CB->getParamAttr(i, Kind).getValueAsType())
      continue;

    CB->removeParamAttr(i, Kind);

    Type *PtrEltTy = ArgsTys[i]->getPointerElementType();
    Attribute NewAttr;
    switch (Kind) {
    case Attribute::ByVal:
      NewAttr = Attribute::getWithByValType(Context, PtrEltTy);
      break;
    case Attribute::StructRet:
      NewAttr = Attribute::getWithStructRetType(Context, PtrEltTy);
      break;
    case Attribute::InAlloca:
      NewAttr = Attribute::getWithInAllocaType(Context, PtrEltTy);
      break;
    default:
      llvm_unreachable("not an upgraded type attribute")::llvm::llvm_unreachable_internal("not an upgraded type attribute"
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 3931);
    }

    CB->addParamAttr(i, NewAttr);
  }
}

if (CB->isInlineAsm()) {
  const InlineAsm *IA = cast<InlineAsm>(CB->getCalledOperand());
  unsigned ArgNo = 0;
  for (const InlineAsm::ConstraintInfo &CI : IA->ParseConstraints()) {
    if (!CI.hasArg())
      continue;

    if (CI.isIndirect && !CB->getAttributes().getParamElementType(ArgNo)) {
      Type *ElemTy = ArgsTys[ArgNo]->getPointerElementType();
      CB->addParamAttr(
          ArgNo, Attribute::get(Context, Attribute::ElementType, ElemTy));
    }

    ArgNo++;
  }
}

switch (CB->getIntrinsicID()) {
case Intrinsic::preserve_array_access_index:
case Intrinsic::preserve_struct_access_index:
  if (!CB->getAttributes().getParamElementType(0)) {
    Type *ElTy = ArgsTys[0]->getPointerElementType();
    Attribute NewAttr = Attribute::get(Context, Attribute::ElementType, ElTy);
    CB->addParamAttr(0, NewAttr);
  }
  break;
default:
  break;
}
3967}

3969/// Lazily parse the specified function body block.
3970Error BitcodeReader::parseFunctionBody(Function *F) {
if (Error Err = Stream.EnterSubBlock(bitc::FUNCTION_BLOCK_ID))
  return Err;

// Unexpected unresolved metadata when parsing function.
if (MDLoader->hasFwdRefs())
  return error("Invalid function metadata: incoming forward references");

InstructionList.clear();
unsigned ModuleValueListSize = ValueList.size();
unsigned ModuleMDLoaderSize = MDLoader->size();

// Add all the function arguments to the value table.
3983#ifndef NDEBUG
unsigned ArgNo = 0;
FunctionType *FTy = FunctionTypes[F];
3986#endif
for (Argument &I : F->args()) {
  assert(I.getType() == FTy->getParamType(ArgNo++) &&(static_cast <bool> (I.getType() == FTy->getParamType
(ArgNo++) && "Incorrect fully specified type for Function Argument"
) ? void (0) : __assert_fail ("I.getType() == FTy->getParamType(ArgNo++) && \"Incorrect fully specified type for Function Argument\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 3989, __extension__
 __PRETTY_FUNCTION__))
         "Incorrect fully specified type for Function Argument")(static_cast <bool> (I.getType() == FTy->getParamType
(ArgNo++) && "Incorrect fully specified type for Function Argument"
) ? void (0) : __assert_fail ("I.getType() == FTy->getParamType(ArgNo++) && \"Incorrect fully specified type for Function Argument\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 3989, __extension__
 __PRETTY_FUNCTION__));
  ValueList.push_back(&I);
}
unsigned NextValueNo = ValueList.size();
BasicBlock *CurBB = nullptr;
unsigned CurBBNo = 0;

DebugLoc LastLoc;
auto getLastInstruction = [&]() -> Instruction * {
  if (CurBB && !CurBB->empty())
    return &CurBB->back();
  else if (CurBBNo && FunctionBBs[CurBBNo - 1] &&
           !FunctionBBs[CurBBNo - 1]->empty())
    return &FunctionBBs[CurBBNo - 1]->back();
  return nullptr;
};

std::vector<OperandBundleDef> OperandBundles;

// Read all the records.
SmallVector<uint64_t, 64> Record;

while (true) {
  Expected<llvm::BitstreamEntry> MaybeEntry = Stream.advance();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  llvm::BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    goto OutOfRecordLoop;

  case BitstreamEntry::SubBlock:
    switch (Entry.ID) {
    default:  // Skip unknown content.
      if (Error Err = Stream.SkipBlock())
        return Err;
      break;
    case bitc::CONSTANTS_BLOCK_ID:
      if (Error Err = parseConstants())
        return Err;
      NextValueNo = ValueList.size();
      break;
    case bitc::VALUE_SYMTAB_BLOCK_ID:
      if (Error Err = parseValueSymbolTable())
        return Err;
      break;
    case bitc::METADATA_ATTACHMENT_ID:
      if (Error Err = MDLoader->parseMetadataAttachment(*F, InstructionList))
        return Err;
      break;
    case bitc::METADATA_BLOCK_ID:
      assert(DeferredMetadataInfo.empty() &&(static_cast <bool> (DeferredMetadataInfo.empty() &&
 "Must read all module-level metadata before function-level")
 ? void (0) : __assert_fail ("DeferredMetadataInfo.empty() && \"Must read all module-level metadata before function-level\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4044, __extension__
 __PRETTY_FUNCTION__))
             "Must read all module-level metadata before function-level")(static_cast <bool> (DeferredMetadataInfo.empty() &&
 "Must read all module-level metadata before function-level")
 ? void (0) : __assert_fail ("DeferredMetadataInfo.empty() && \"Must read all module-level metadata before function-level\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4044, __extension__
 __PRETTY_FUNCTION__));
      if (Error Err = MDLoader->parseFunctionMetadata())
        return Err;
      break;
    case bitc::USELIST_BLOCK_ID:
      if (Error Err = parseUseLists())
        return Err;
      break;
    }
    continue;

  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Read a record.
  Record.clear();
  Instruction *I = nullptr;
  Expected<unsigned> MaybeBitCode = Stream.readRecord(Entry.ID, Record);
  if (!MaybeBitCode)
    return MaybeBitCode.takeError();
  switch (unsigned BitCode = MaybeBitCode.get()) {
  default: // Default behavior: reject
    return error("Invalid value");
  case bitc::FUNC_CODE_DECLAREBLOCKS: {   // DECLAREBLOCKS: [nblocks]
    if (Record.empty() || Record[0] == 0)
      return error("Invalid record");
    // Create all the basic blocks for the function.
    FunctionBBs.resize(Record[0]);

    // See if anything took the address of blocks in this function.
    auto BBFRI = BasicBlockFwdRefs.find(F);
    if (BBFRI == BasicBlockFwdRefs.end()) {
      for (BasicBlock *&BB : FunctionBBs)
        BB = BasicBlock::Create(Context, "", F);
    } else {
      auto &BBRefs = BBFRI->second;
      // Check for invalid basic block references.
      if (BBRefs.size() > FunctionBBs.size())
        return error("Invalid ID");
      assert(!BBRefs.empty() && "Unexpected empty array")(static_cast <bool> (!BBRefs.empty() && "Unexpected empty array"
) ? void (0) : __assert_fail ("!BBRefs.empty() && \"Unexpected empty array\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4085, __extension__
 __PRETTY_FUNCTION__));
      assert(!BBRefs.front() && "Invalid reference to entry block")(static_cast <bool> (!BBRefs.front() && "Invalid reference to entry block"
) ? void (0) : __assert_fail ("!BBRefs.front() && \"Invalid reference to entry block\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4086, __extension__
 __PRETTY_FUNCTION__));
      for (unsigned I = 0, E = FunctionBBs.size(), RE = BBRefs.size(); I != E;
           ++I)
        if (I < RE && BBRefs[I]) {
          BBRefs[I]->insertInto(F);
          FunctionBBs[I] = BBRefs[I];
        } else {
          FunctionBBs[I] = BasicBlock::Create(Context, "", F);
        }

      // Erase from the table.
      BasicBlockFwdRefs.erase(BBFRI);
    }

    CurBB = FunctionBBs[0];
    continue;
  }

  case bitc::FUNC_CODE_DEBUG_LOC_AGAIN:  // DEBUG_LOC_AGAIN
    // This record indicates that the last instruction is at the same
    // location as the previous instruction with a location.
    I = getLastInstruction();

    if (!I)
      return error("Invalid record");
    I->setDebugLoc(LastLoc);
    I = nullptr;
    continue;

  case bitc::FUNC_CODE_DEBUG_LOC: {      // DEBUG_LOC: [line, col, scope, ia]
    I = getLastInstruction();
    if (!I || Record.size() < 4)
      return error("Invalid record");

    unsigned Line = Record[0], Col = Record[1];
    unsigned ScopeID = Record[2], IAID = Record[3];
    bool isImplicitCode = Record.size() == 5 && Record[4];

    MDNode *Scope = nullptr, *IA = nullptr;
    if (ScopeID) {
      Scope = dyn_cast_or_null<MDNode>(
          MDLoader->getMetadataFwdRefOrLoad(ScopeID - 1));
      if (!Scope)
        return error("Invalid record");
    }
    if (IAID) {
      IA = dyn_cast_or_null<MDNode>(
          MDLoader->getMetadataFwdRefOrLoad(IAID - 1));
      if (!IA)
        return error("Invalid record");
    }
    LastLoc = DILocation::get(Scope->getContext(), Line, Col, Scope, IA,
                              isImplicitCode);
    I->setDebugLoc(LastLoc);
    I = nullptr;
    continue;
  }
  case bitc::FUNC_CODE_INST_UNOP: {    // UNOP: [opval, ty, opcode]
    unsigned OpNum = 0;
    Value *LHS;
    if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
        OpNum+1 > Record.size())
      return error("Invalid record");

    int Opc = getDecodedUnaryOpcode(Record[OpNum++], LHS->getType());
    if (Opc == -1)
      return error("Invalid record");
    I = UnaryOperator::Create((Instruction::UnaryOps)Opc, LHS);
    InstructionList.push_back(I);
    if (OpNum < Record.size()) {
      if (isa<FPMathOperator>(I)) {
        FastMathFlags FMF = getDecodedFastMathFlags(Record[OpNum]);
        if (FMF.any())
          I->setFastMathFlags(FMF);
      }
    }
    break;
  }
  case bitc::FUNC_CODE_INST_BINOP: {    // BINOP: [opval, ty, opval, opcode]
    unsigned OpNum = 0;
    Value *LHS, *RHS;
    if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
        popValue(Record, OpNum, NextValueNo, LHS->getType(), RHS) ||
        OpNum+1 > Record.size())
      return error("Invalid record");

    int Opc = getDecodedBinaryOpcode(Record[OpNum++], LHS->getType());
    if (Opc == -1)
      return error("Invalid record");
    I = BinaryOperator::Create((Instruction::BinaryOps)Opc, LHS, RHS);
    InstructionList.push_back(I);
    if (OpNum < Record.size()) {
      if (Opc == Instruction::Add ||
          Opc == Instruction::Sub ||
          Opc == Instruction::Mul ||
          Opc == Instruction::Shl) {
        if (Record[OpNum] & (1 << bitc::OBO_NO_SIGNED_WRAP))
          cast<BinaryOperator>(I)->setHasNoSignedWrap(true);
        if (Record[OpNum] & (1 << bitc::OBO_NO_UNSIGNED_WRAP))
          cast<BinaryOperator>(I)->setHasNoUnsignedWrap(true);
      } else if (Opc == Instruction::SDiv ||
                 Opc == Instruction::UDiv ||
                 Opc == Instruction::LShr ||
                 Opc == Instruction::AShr) {
        if (Record[OpNum] & (1 << bitc::PEO_EXACT))
          cast<BinaryOperator>(I)->setIsExact(true);
      } else if (isa<FPMathOperator>(I)) {
        FastMathFlags FMF = getDecodedFastMathFlags(Record[OpNum]);
        if (FMF.any())
          I->setFastMathFlags(FMF);
      }

    }
    break;
  }
  case bitc::FUNC_CODE_INST_CAST: {    // CAST: [opval, opty, destty, castopc]
    unsigned OpNum = 0;
    Value *Op;
    if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
        OpNum+2 != Record.size())
      return error("Invalid record");

    Type *ResTy = getTypeByID(Record[OpNum]);
    int Opc = getDecodedCastOpcode(Record[OpNum + 1]);
    if (Opc == -1 || !ResTy)
      return error("Invalid record");
    Instruction *Temp = nullptr;
    if ((I = UpgradeBitCastInst(Opc, Op, ResTy, Temp))) {
      if (Temp) {
        InstructionList.push_back(Temp);
        assert(CurBB && "No current BB?")(static_cast <bool> (CurBB && "No current BB?")
 ? void (0) : __assert_fail ("CurBB && \"No current BB?\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4216, __extension__
 __PRETTY_FUNCTION__));
        CurBB->getInstList().push_back(Temp);
      }
    } else {
      auto CastOp = (Instruction::CastOps)Opc;
      if (!CastInst::castIsValid(CastOp, Op, ResTy))
        return error("Invalid cast");
      I = CastInst::Create(CastOp, Op, ResTy);
    }
    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_INBOUNDS_GEP_OLD:
  case bitc::FUNC_CODE_INST_GEP_OLD:
  case bitc::FUNC_CODE_INST_GEP: { // GEP: type, [n x operands]
    unsigned OpNum = 0;

    Type *Ty;
    bool InBounds;

    if (BitCode == bitc::FUNC_CODE_INST_GEP) {
      InBounds = Record[OpNum++];
      Ty = getTypeByID(Record[OpNum++]);
    } else {
      InBounds = BitCode == bitc::FUNC_CODE_INST_INBOUNDS_GEP_OLD;
      Ty = nullptr;
    }

    Value *BasePtr;
    if (getValueTypePair(Record, OpNum, NextValueNo, BasePtr))
      return error("Invalid record");

    if (!Ty) {
      Ty = BasePtr->getType()->getScalarType()->getPointerElementType();
    } else if (!cast<PointerType>(BasePtr->getType()->getScalarType())
                    ->isOpaqueOrPointeeTypeMatches(Ty)) {
      return error(
          "Explicit gep type does not match pointee type of pointer operand");
    }

    SmallVector<Value*, 16> GEPIdx;
    while (OpNum != Record.size()) {
      Value *Op;
      if (getValueTypePair(Record, OpNum, NextValueNo, Op))
        return error("Invalid record");
      GEPIdx.push_back(Op);
    }

    I = GetElementPtrInst::Create(Ty, BasePtr, GEPIdx);

    InstructionList.push_back(I);
    if (InBounds)
      cast<GetElementPtrInst>(I)->setIsInBounds(true);
    break;
  }

  case bitc::FUNC_CODE_INST_EXTRACTVAL: {
                                     // EXTRACTVAL: [opty, opval, n x indices]
    unsigned OpNum = 0;
    Value *Agg;
    if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
      return error("Invalid record");
    Type *Ty = Agg->getType();

    unsigned RecSize = Record.size();
    if (OpNum == RecSize)
      return error("EXTRACTVAL: Invalid instruction with 0 indices");

    SmallVector<unsigned, 4> EXTRACTVALIdx;
    for (; OpNum != RecSize; ++OpNum) {
      bool IsArray = Ty->isArrayTy();
      bool IsStruct = Ty->isStructTy();
      uint64_t Index = Record[OpNum];

      if (!IsStruct && !IsArray)
        return error("EXTRACTVAL: Invalid type");
      if ((unsigned)Index != Index)
        return error("Invalid value");
      if (IsStruct && Index >= Ty->getStructNumElements())
        return error("EXTRACTVAL: Invalid struct index");
      if (IsArray && Index >= Ty->getArrayNumElements())
        return error("EXTRACTVAL: Invalid array index");
      EXTRACTVALIdx.push_back((unsigned)Index);

      if (IsStruct)
        Ty = Ty->getStructElementType(Index);
      else
        Ty = Ty->getArrayElementType();
    }

    I = ExtractValueInst::Create(Agg, EXTRACTVALIdx);
    InstructionList.push_back(I);
    break;
  }

  case bitc::FUNC_CODE_INST_INSERTVAL: {
                         // INSERTVAL: [opty, opval, opty, opval, n x indices]
    unsigned OpNum = 0;
    Value *Agg;
    if (getValueTypePair(Record, OpNum, NextValueNo, Agg))
      return error("Invalid record");
    Value *Val;
    if (getValueTypePair(Record, OpNum, NextValueNo, Val))
      return error("Invalid record");

    unsigned RecSize = Record.size();
    if (OpNum == RecSize)
      return error("INSERTVAL: Invalid instruction with 0 indices");

    SmallVector<unsigned, 4> INSERTVALIdx;
    Type *CurTy = Agg->getType();
    for (; OpNum != RecSize; ++OpNum) {
      bool IsArray = CurTy->isArrayTy();
      bool IsStruct = CurTy->isStructTy();
      uint64_t Index = Record[OpNum];

      if (!IsStruct && !IsArray)
        return error("INSERTVAL: Invalid type");
      if ((unsigned)Index != Index)
        return error("Invalid value");
      if (IsStruct && Index >= CurTy->getStructNumElements())
        return error("INSERTVAL: Invalid struct index");
      if (IsArray && Index >= CurTy->getArrayNumElements())
        return error("INSERTVAL: Invalid array index");

      INSERTVALIdx.push_back((unsigned)Index);
      if (IsStruct)
        CurTy = CurTy->getStructElementType(Index);
      else
        CurTy = CurTy->getArrayElementType();
    }

    if (CurTy != Val->getType())
      return error("Inserted value type doesn't match aggregate type");

    I = InsertValueInst::Create(Agg, Val, INSERTVALIdx);
    InstructionList.push_back(I);
    break;
  }

  case bitc::FUNC_CODE_INST_SELECT: { // SELECT: [opval, ty, opval, opval]
    // obsolete form of select
    // handles select i1 ... in old bitcode
    unsigned OpNum = 0;
    Value *TrueVal, *FalseVal, *Cond;
    if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
        popValue(Record, OpNum, NextValueNo, TrueVal->getType(), FalseVal) ||
        popValue(Record, OpNum, NextValueNo, Type::getInt1Ty(Context), Cond))
      return error("Invalid record");

    I = SelectInst::Create(Cond, TrueVal, FalseVal);
    InstructionList.push_back(I);
    break;
  }

  case bitc::FUNC_CODE_INST_VSELECT: {// VSELECT: [ty,opval,opval,predty,pred]
    // new form of select
    // handles select i1 or select [N x i1]
    unsigned OpNum = 0;
    Value *TrueVal, *FalseVal, *Cond;
    if (getValueTypePair(Record, OpNum, NextValueNo, TrueVal) ||
        popValue(Record, OpNum, NextValueNo, TrueVal->getType(), FalseVal) ||
        getValueTypePair(Record, OpNum, NextValueNo, Cond))
      return error("Invalid record");

    // select condition can be either i1 or [N x i1]
    if (VectorType* vector_type =
        dyn_cast<VectorType>(Cond->getType())) {
      // expect <n x i1>
      if (vector_type->getElementType() != Type::getInt1Ty(Context))
        return error("Invalid type for value");
    } else {
      // expect i1
      if (Cond->getType() != Type::getInt1Ty(Context))
        return error("Invalid type for value");
    }

    I = SelectInst::Create(Cond, TrueVal, FalseVal);
    InstructionList.push_back(I);
    if (OpNum < Record.size() && isa<FPMathOperator>(I)) {
      FastMathFlags FMF = getDecodedFastMathFlags(Record[OpNum]);
      if (FMF.any())
        I->setFastMathFlags(FMF);
    }
    break;
  }

  case bitc::FUNC_CODE_INST_EXTRACTELT: { // EXTRACTELT: [opty, opval, opval]
    unsigned OpNum = 0;
    Value *Vec, *Idx;
    if (getValueTypePair(Record, OpNum, NextValueNo, Vec) ||
        getValueTypePair(Record, OpNum, NextValueNo, Idx))
      return error("Invalid record");
    if (!Vec->getType()->isVectorTy())
      return error("Invalid type for value");
    I = ExtractElementInst::Create(Vec, Idx);
    InstructionList.push_back(I);
    break;
  }

  case bitc::FUNC_CODE_INST_INSERTELT: { // INSERTELT: [ty, opval,opval,opval]
    unsigned OpNum = 0;
    Value *Vec, *Elt, *Idx;
    if (getValueTypePair(Record, OpNum, NextValueNo, Vec))
      return error("Invalid record");
    if (!Vec->getType()->isVectorTy())
      return error("Invalid type for value");
    if (popValue(Record, OpNum, NextValueNo,
                 cast<VectorType>(Vec->getType())->getElementType(), Elt) ||
        getValueTypePair(Record, OpNum, NextValueNo, Idx))
      return error("Invalid record");
    I = InsertElementInst::Create(Vec, Elt, Idx);
    InstructionList.push_back(I);
    break;
  }

  case bitc::FUNC_CODE_INST_SHUFFLEVEC: {// SHUFFLEVEC: [opval,ty,opval,opval]
    unsigned OpNum = 0;
    Value *Vec1, *Vec2, *Mask;
    if (getValueTypePair(Record, OpNum, NextValueNo, Vec1) ||
        popValue(Record, OpNum, NextValueNo, Vec1->getType(), Vec2))
      return error("Invalid record");

    if (getValueTypePair(Record, OpNum, NextValueNo, Mask))
      return error("Invalid record");
    if (!Vec1->getType()->isVectorTy() || !Vec2->getType()->isVectorTy())
      return error("Invalid type for value");

    I = new ShuffleVectorInst(Vec1, Vec2, Mask);
    InstructionList.push_back(I);
    break;
  }

  case bitc::FUNC_CODE_INST_CMP:   // CMP: [opty, opval, opval, pred]
    // Old form of ICmp/FCmp returning bool
    // Existed to differentiate between icmp/fcmp and vicmp/vfcmp which were
    // both legal on vectors but had different behaviour.
  case bitc::FUNC_CODE_INST_CMP2: { // CMP2: [opty, opval, opval, pred]
    // FCmp/ICmp returning bool or vector of bool

    unsigned OpNum = 0;
    Value *LHS, *RHS;
    if (getValueTypePair(Record, OpNum, NextValueNo, LHS) ||
        popValue(Record, OpNum, NextValueNo, LHS->getType(), RHS))
      return error("Invalid record");

    if (OpNum >= Record.size())
      return error(
          "Invalid record: operand number exceeded available operands");

    unsigned PredVal = Record[OpNum];
    bool IsFP = LHS->getType()->isFPOrFPVectorTy();
    FastMathFlags FMF;
    if (IsFP && Record.size() > OpNum+1)
      FMF = getDecodedFastMathFlags(Record[++OpNum]);

    if (OpNum+1 != Record.size())
      return error("Invalid record");

    if (LHS->getType()->isFPOrFPVectorTy())
      I = new FCmpInst((FCmpInst::Predicate)PredVal, LHS, RHS);
    else
      I = new ICmpInst((ICmpInst::Predicate)PredVal, LHS, RHS);

    if (FMF.any())
      I->setFastMathFlags(FMF);
    InstructionList.push_back(I);
    break;
  }

  case bitc::FUNC_CODE_INST_RET: // RET: [opty,opval<optional>]
    {
      unsigned Size = Record.size();
      if (Size == 0) {
        I = ReturnInst::Create(Context);
        InstructionList.push_back(I);
        break;
      }

      unsigned OpNum = 0;
      Value *Op = nullptr;
      if (getValueTypePair(Record, OpNum, NextValueNo, Op))
        return error("Invalid record");
      if (OpNum != Record.size())
        return error("Invalid record");

      I = ReturnInst::Create(Context, Op);
      InstructionList.push_back(I);
      break;
    }
  case bitc::FUNC_CODE_INST_BR: { // BR: [bb#, bb#, opval] or [bb#]
    if (Record.size() != 1 && Record.size() != 3)
      return error("Invalid record");
    BasicBlock *TrueDest = getBasicBlock(Record[0]);
    if (!TrueDest)
      return error("Invalid record");

    if (Record.size() == 1) {
      I = BranchInst::Create(TrueDest);
      InstructionList.push_back(I);
    }
    else {
      BasicBlock *FalseDest = getBasicBlock(Record[1]);
      Value *Cond = getValue(Record, 2, NextValueNo,
                             Type::getInt1Ty(Context));
      if (!FalseDest || !Cond)
        return error("Invalid record");
      I = BranchInst::Create(TrueDest, FalseDest, Cond);
      InstructionList.push_back(I);
    }
    break;
  }
  case bitc::FUNC_CODE_INST_CLEANUPRET: { // CLEANUPRET: [val] or [val,bb#]
    if (Record.size() != 1 && Record.size() != 2)
      return error("Invalid record");
    unsigned Idx = 0;
    Value *CleanupPad =
        getValue(Record, Idx++, NextValueNo, Type::getTokenTy(Context));
    if (!CleanupPad)
      return error("Invalid record");
    BasicBlock *UnwindDest = nullptr;
    if (Record.size() == 2) {
      UnwindDest = getBasicBlock(Record[Idx++]);
      if (!UnwindDest)
        return error("Invalid record");
    }

    I = CleanupReturnInst::Create(CleanupPad, UnwindDest);
    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_CATCHRET: { // CATCHRET: [val,bb#]
    if (Record.size() != 2)
      return error("Invalid record");
    unsigned Idx = 0;
    Value *CatchPad =
        getValue(Record, Idx++, NextValueNo, Type::getTokenTy(Context));
    if (!CatchPad)
      return error("Invalid record");
    BasicBlock *BB = getBasicBlock(Record[Idx++]);
    if (!BB)
      return error("Invalid record");

    I = CatchReturnInst::Create(CatchPad, BB);
    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_CATCHSWITCH: { // CATCHSWITCH: [tok,num,(bb)*,bb?]
    // We must have, at minimum, the outer scope and the number of arguments.
    if (Record.size() < 2)
      return error("Invalid record");

    unsigned Idx = 0;

    Value *ParentPad =
        getValue(Record, Idx++, NextValueNo, Type::getTokenTy(Context));

    unsigned NumHandlers = Record[Idx++];

    SmallVector<BasicBlock *, 2> Handlers;
    for (unsigned Op = 0; Op != NumHandlers; ++Op) {
      BasicBlock *BB = getBasicBlock(Record[Idx++]);
      if (!BB)
        return error("Invalid record");
      Handlers.push_back(BB);
    }

    BasicBlock *UnwindDest = nullptr;
    if (Idx + 1 == Record.size()) {
      UnwindDest = getBasicBlock(Record[Idx++]);
      if (!UnwindDest)
        return error("Invalid record");
    }

    if (Record.size() != Idx)
      return error("Invalid record");

    auto *CatchSwitch =
        CatchSwitchInst::Create(ParentPad, UnwindDest, NumHandlers);
    for (BasicBlock *Handler : Handlers)
      CatchSwitch->addHandler(Handler);
    I = CatchSwitch;
    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_CATCHPAD:
  case bitc::FUNC_CODE_INST_CLEANUPPAD: { // [tok,num,(ty,val)*]
    // We must have, at minimum, the outer scope and the number of arguments.
    if (Record.size() < 2)
      return error("Invalid record");

    unsigned Idx = 0;

    Value *ParentPad =
        getValue(Record, Idx++, NextValueNo, Type::getTokenTy(Context));

    unsigned NumArgOperands = Record[Idx++];

    SmallVector<Value *, 2> Args;
    for (unsigned Op = 0; Op != NumArgOperands; ++Op) {
      Value *Val;
      if (getValueTypePair(Record, Idx, NextValueNo, Val))
        return error("Invalid record");
      Args.push_back(Val);
    }

    if (Record.size() != Idx)
      return error("Invalid record");

    if (BitCode == bitc::FUNC_CODE_INST_CLEANUPPAD)
      I = CleanupPadInst::Create(ParentPad, Args);
    else
      I = CatchPadInst::Create(ParentPad, Args);
    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_SWITCH: { // SWITCH: [opty, op0, op1, ...]
    // Check magic
    if ((Record[0] >> 16) == SWITCH_INST_MAGIC) {
      // "New" SwitchInst format with case ranges. The changes to write this
      // format were reverted but we still recognize bitcode that uses it.
      // Hopefully someday we will have support for case ranges and can use
      // this format again.

      Type *OpTy = getTypeByID(Record[1]);
      unsigned ValueBitWidth = cast<IntegerType>(OpTy)->getBitWidth();

      Value *Cond = getValue(Record, 2, NextValueNo, OpTy);
      BasicBlock *Default = getBasicBlock(Record[3]);
      if (!OpTy || !Cond || !Default)
        return error("Invalid record");

      unsigned NumCases = Record[4];

      SwitchInst *SI = SwitchInst::Create(Cond, Default, NumCases);
      InstructionList.push_back(SI);

      unsigned CurIdx = 5;
      for (unsigned i = 0; i != NumCases; ++i) {
        SmallVector<ConstantInt*, 1> CaseVals;
        unsigned NumItems = Record[CurIdx++];
        for (unsigned ci = 0; ci != NumItems; ++ci) {
          bool isSingleNumber = Record[CurIdx++];

          APInt Low;
          unsigned ActiveWords = 1;
          if (ValueBitWidth > 64)
            ActiveWords = Record[CurIdx++];
          Low = readWideAPInt(makeArrayRef(&Record[CurIdx], ActiveWords),
                              ValueBitWidth);
          CurIdx += ActiveWords;

          if (!isSingleNumber) {
            ActiveWords = 1;
            if (ValueBitWidth > 64)
              ActiveWords = Record[CurIdx++];
            APInt High = readWideAPInt(
                makeArrayRef(&Record[CurIdx], ActiveWords), ValueBitWidth);
            CurIdx += ActiveWords;

            // FIXME: It is not clear whether values in the range should be
            // compared as signed or unsigned values. The partially
            // implemented changes that used this format in the past used
            // unsigned comparisons.
            for ( ; Low.ule(High); ++Low)
              CaseVals.push_back(ConstantInt::get(Context, Low));
          } else
            CaseVals.push_back(ConstantInt::get(Context, Low));
        }
        BasicBlock *DestBB = getBasicBlock(Record[CurIdx++]);
        for (ConstantInt *Cst : CaseVals)
          SI->addCase(Cst, DestBB);
      }
      I = SI;
      break;
    }

    // Old SwitchInst format without case ranges.

    if (Record.size() < 3 || (Record.size() & 1) == 0)
      return error("Invalid record");
    Type *OpTy = getTypeByID(Record[0]);
    Value *Cond = getValue(Record, 1, NextValueNo, OpTy);
    BasicBlock *Default = getBasicBlock(Record[2]);
    if (!OpTy || !Cond || !Default)
      return error("Invalid record");
    unsigned NumCases = (Record.size()-3)/2;
    SwitchInst *SI = SwitchInst::Create(Cond, Default, NumCases);
    InstructionList.push_back(SI);
    for (unsigned i = 0, e = NumCases; i != e; ++i) {
      ConstantInt *CaseVal =
        dyn_cast_or_null<ConstantInt>(getFnValueByID(Record[3+i*2], OpTy));
      BasicBlock *DestBB = getBasicBlock(Record[1+3+i*2]);
      if (!CaseVal || !DestBB) {
        delete SI;
        return error("Invalid record");
      }
      SI->addCase(CaseVal, DestBB);
    }
    I = SI;
    break;
  }
  case bitc::FUNC_CODE_INST_INDIRECTBR: { // INDIRECTBR: [opty, op0, op1, ...]
    if (Record.size() < 2)
      return error("Invalid record");
    Type *OpTy = getTypeByID(Record[0]);
    Value *Address = getValue(Record, 1, NextValueNo, OpTy);
    if (!OpTy || !Address)
      return error("Invalid record");
    unsigned NumDests = Record.size()-2;
    IndirectBrInst *IBI = IndirectBrInst::Create(Address, NumDests);
    InstructionList.push_back(IBI);
    for (unsigned i = 0, e = NumDests; i != e; ++i) {
      if (BasicBlock *DestBB = getBasicBlock(Record[2+i])) {
        IBI->addDestination(DestBB);
      } else {
        delete IBI;
        return error("Invalid record");
      }
    }
    I = IBI;
    break;
  }

  case bitc::FUNC_CODE_INST_INVOKE: {
    // INVOKE: [attrs, cc, normBB, unwindBB, fnty, op0,op1,op2, ...]
    if (Record.size() < 4)
      return error("Invalid record");
    unsigned OpNum = 0;
    AttributeList PAL = getAttributes(Record[OpNum++]);
    unsigned CCInfo = Record[OpNum++];
    BasicBlock *NormalBB = getBasicBlock(Record[OpNum++]);
    BasicBlock *UnwindBB = getBasicBlock(Record[OpNum++]);

    FunctionType *FTy = nullptr;
    if ((CCInfo >> 13) & 1) {
      FTy = dyn_cast<FunctionType>(getTypeByID(Record[OpNum++]));
      if (!FTy)
        return error("Explicit invoke type is not a function type");
    }

    Value *Callee;
    if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
      return error("Invalid record");

    PointerType *CalleeTy = dyn_cast<PointerType>(Callee->getType());
    if (!CalleeTy)
      return error("Callee is not a pointer");
    if (!FTy) {
      FTy =
          dyn_cast<FunctionType>(Callee->getType()->getPointerElementType());
      if (!FTy)
        return error("Callee is not of pointer to function type");
    } else if (!CalleeTy->isOpaqueOrPointeeTypeMatches(FTy))
      return error("Explicit invoke type does not match pointee type of "
                   "callee operand");
    if (Record.size() < FTy->getNumParams() + OpNum)
      return error("Insufficient operands to call");

    SmallVector<Value*, 16> Ops;
    SmallVector<Type *, 16> ArgsTys;
    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
      Ops.push_back(getValue(Record, OpNum, NextValueNo,
                             FTy->getParamType(i)));
      ArgsTys.push_back(FTy->getParamType(i));
      if (!Ops.back())
        return error("Invalid record");
    }

    if (!FTy->isVarArg()) {
      if (Record.size() != OpNum)
        return error("Invalid record");
    } else {
      // Read type/value pairs for varargs params.
      while (OpNum != Record.size()) {
        Value *Op;
        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
          return error("Invalid record");
        Ops.push_back(Op);
        ArgsTys.push_back(Op->getType());
      }
    }

    I = InvokeInst::Create(FTy, Callee, NormalBB, UnwindBB, Ops,
                           OperandBundles);
    OperandBundles.clear();
    InstructionList.push_back(I);
    cast<InvokeInst>(I)->setCallingConv(
        static_cast<CallingConv::ID>(CallingConv::MaxID & CCInfo));
    cast<InvokeInst>(I)->setAttributes(PAL);
    propagateAttributeTypes(cast<CallBase>(I), ArgsTys);

    break;
  }
  case bitc::FUNC_CODE_INST_RESUME: { // RESUME: [opval]
    unsigned Idx = 0;
    Value *Val = nullptr;
    if (getValueTypePair(Record, Idx, NextValueNo, Val))
      return error("Invalid record");
    I = ResumeInst::Create(Val);
    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_CALLBR: {
    // CALLBR: [attr, cc, norm, transfs, fty, fnid, args]
    unsigned OpNum = 0;
    AttributeList PAL = getAttributes(Record[OpNum++]);
    unsigned CCInfo = Record[OpNum++];

    BasicBlock *DefaultDest = getBasicBlock(Record[OpNum++]);
    unsigned NumIndirectDests = Record[OpNum++];
    SmallVector<BasicBlock *, 16> IndirectDests;
    for (unsigned i = 0, e = NumIndirectDests; i != e; ++i)
      IndirectDests.push_back(getBasicBlock(Record[OpNum++]));

    FunctionType *FTy = nullptr;
    if ((CCInfo >> bitc::CALL_EXPLICIT_TYPE) & 1) {
      FTy = dyn_cast<FunctionType>(getTypeByID(Record[OpNum++]));
      if (!FTy)
        return error("Explicit call type is not a function type");
    }

    Value *Callee;
    if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
      return error("Invalid record");

    PointerType *OpTy = dyn_cast<PointerType>(Callee->getType());
    if (!OpTy)
      return error("Callee is not a pointer type");
    if (!FTy) {
      FTy =
          dyn_cast<FunctionType>(Callee->getType()->getPointerElementType());
      if (!FTy)
        return error("Callee is not of pointer to function type");
    } else if (!OpTy->isOpaqueOrPointeeTypeMatches(FTy))
      return error("Explicit call type does not match pointee type of "
                   "callee operand");
    if (Record.size() < FTy->getNumParams() + OpNum)
      return error("Insufficient operands to call");

    SmallVector<Value*, 16> Args;
    SmallVector<Type *, 16> ArgsTys;
    // Read the fixed params.
    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
      Value *Arg;
      if (FTy->getParamType(i)->isLabelTy())
        Arg = getBasicBlock(Record[OpNum]);
      else
        Arg = getValue(Record, OpNum, NextValueNo, FTy->getParamType(i));
      if (!Arg)
        return error("Invalid record");
      Args.push_back(Arg);
      ArgsTys.push_back(Arg->getType());
    }

    // Read type/value pairs for varargs params.
    if (!FTy->isVarArg()) {
      if (OpNum != Record.size())
        return error("Invalid record");
    } else {
      while (OpNum != Record.size()) {
        Value *Op;
        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
          return error("Invalid record");
        Args.push_back(Op);
        ArgsTys.push_back(Op->getType());
      }
    }

    I = CallBrInst::Create(FTy, Callee, DefaultDest, IndirectDests, Args,
                           OperandBundles);
    OperandBundles.clear();
    InstructionList.push_back(I);
    cast<CallBrInst>(I)->setCallingConv(
        static_cast<CallingConv::ID>((0x7ff & CCInfo) >> bitc::CALL_CCONV));
    cast<CallBrInst>(I)->setAttributes(PAL);
    propagateAttributeTypes(cast<CallBase>(I), ArgsTys);
    break;
  }
  case bitc::FUNC_CODE_INST_UNREACHABLE: // UNREACHABLE
    I = new UnreachableInst(Context);
    InstructionList.push_back(I);
    break;
  case bitc::FUNC_CODE_INST_PHI: { // PHI: [ty, val0,bb0, ...]
    if (Record.empty())
      return error("Invalid record");
    // The first record specifies the type.
    Type *Ty = getTypeByID(Record[0]);
    if (!Ty)
      return error("Invalid record");

    // Phi arguments are pairs of records of [value, basic block].
    // There is an optional final record for fast-math-flags if this phi has a
    // floating-point type.
    size_t NumArgs = (Record.size() - 1) / 2;
    PHINode *PN = PHINode::Create(Ty, NumArgs);
    if ((Record.size() - 1) % 2 == 1 && !isa<FPMathOperator>(PN))
      return error("Invalid record");
    InstructionList.push_back(PN);

    for (unsigned i = 0; i != NumArgs; i++) {
      Value *V;
      // With the new function encoding, it is possible that operands have
      // negative IDs (for forward references).  Use a signed VBR
      // representation to keep the encoding small.
      if (UseRelativeIDs)
        V = getValueSigned(Record, i * 2 + 1, NextValueNo, Ty);
      else
        V = getValue(Record, i * 2 + 1, NextValueNo, Ty);
      BasicBlock *BB = getBasicBlock(Record[i * 2 + 2]);
      if (!V || !BB)
        return error("Invalid record");
      PN->addIncoming(V, BB);
    }
    I = PN;

    // If there are an even number of records, the final record must be FMF.
    if (Record.size() % 2 == 0) {
      assert(isa<FPMathOperator>(I) && "Unexpected phi type")(static_cast <bool> (isa<FPMathOperator>(I) &&
 "Unexpected phi type") ? void (0) : __assert_fail ("isa<FPMathOperator>(I) && \"Unexpected phi type\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4934, __extension__
 __PRETTY_FUNCTION__));
      FastMathFlags FMF = getDecodedFastMathFlags(Record[Record.size() - 1]);
      if (FMF.any())
        I->setFastMathFlags(FMF);
    }

    break;
  }

  case bitc::FUNC_CODE_INST_LANDINGPAD:
  case bitc::FUNC_CODE_INST_LANDINGPAD_OLD: {
    // LANDINGPAD: [ty, val, val, num, (id0,val0 ...)?]
    unsigned Idx = 0;
    if (BitCode == bitc::FUNC_CODE_INST_LANDINGPAD) {
      if (Record.size() < 3)
        return error("Invalid record");
    } else {
      assert(BitCode == bitc::FUNC_CODE_INST_LANDINGPAD_OLD)(static_cast <bool> (BitCode == bitc::FUNC_CODE_INST_LANDINGPAD_OLD
) ? void (0) : __assert_fail ("BitCode == bitc::FUNC_CODE_INST_LANDINGPAD_OLD"
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4951, __extension__
 __PRETTY_FUNCTION__));
      if (Record.size() < 4)
        return error("Invalid record");
    }
    Type *Ty = getTypeByID(Record[Idx++]);
    if (!Ty)
      return error("Invalid record");
    if (BitCode == bitc::FUNC_CODE_INST_LANDINGPAD_OLD) {
      Value *PersFn = nullptr;
      if (getValueTypePair(Record, Idx, NextValueNo, PersFn))
        return error("Invalid record");

      if (!F->hasPersonalityFn())
        F->setPersonalityFn(cast<Constant>(PersFn));
      else if (F->getPersonalityFn() != cast<Constant>(PersFn))
        return error("Personality function mismatch");
    }

    bool IsCleanup = !!Record[Idx++];
    unsigned NumClauses = Record[Idx++];
    LandingPadInst *LP = LandingPadInst::Create(Ty, NumClauses);
    LP->setCleanup(IsCleanup);
    for (unsigned J = 0; J != NumClauses; ++J) {
      LandingPadInst::ClauseType CT =
        LandingPadInst::ClauseType(Record[Idx++]); (void)CT;
      Value *Val;

      if (getValueTypePair(Record, Idx, NextValueNo, Val)) {
        delete LP;
        return error("Invalid record");
      }

      assert((CT != LandingPadInst::Catch ||(static_cast <bool> ((CT != LandingPadInst::Catch || !isa
<ArrayType>(Val->getType())) && "Catch clause has a invalid type!"
) ? void (0) : __assert_fail ("(CT != LandingPadInst::Catch || !isa<ArrayType>(Val->getType())) && \"Catch clause has a invalid type!\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4985, __extension__
 __PRETTY_FUNCTION__))
              !isa<ArrayType>(Val->getType())) &&(static_cast <bool> ((CT != LandingPadInst::Catch || !isa
<ArrayType>(Val->getType())) && "Catch clause has a invalid type!"
) ? void (0) : __assert_fail ("(CT != LandingPadInst::Catch || !isa<ArrayType>(Val->getType())) && \"Catch clause has a invalid type!\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4985, __extension__
 __PRETTY_FUNCTION__))
             "Catch clause has a invalid type!")(static_cast <bool> ((CT != LandingPadInst::Catch || !isa
<ArrayType>(Val->getType())) && "Catch clause has a invalid type!"
) ? void (0) : __assert_fail ("(CT != LandingPadInst::Catch || !isa<ArrayType>(Val->getType())) && \"Catch clause has a invalid type!\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4985, __extension__
 __PRETTY_FUNCTION__));
      assert((CT != LandingPadInst::Filter ||(static_cast <bool> ((CT != LandingPadInst::Filter || isa
<ArrayType>(Val->getType())) && "Filter clause has invalid type!"
) ? void (0) : __assert_fail ("(CT != LandingPadInst::Filter || isa<ArrayType>(Val->getType())) && \"Filter clause has invalid type!\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4988, __extension__
 __PRETTY_FUNCTION__))
              isa<ArrayType>(Val->getType())) &&(static_cast <bool> ((CT != LandingPadInst::Filter || isa
<ArrayType>(Val->getType())) && "Filter clause has invalid type!"
) ? void (0) : __assert_fail ("(CT != LandingPadInst::Filter || isa<ArrayType>(Val->getType())) && \"Filter clause has invalid type!\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4988, __extension__
 __PRETTY_FUNCTION__))
             "Filter clause has invalid type!")(static_cast <bool> ((CT != LandingPadInst::Filter || isa
<ArrayType>(Val->getType())) && "Filter clause has invalid type!"
) ? void (0) : __assert_fail ("(CT != LandingPadInst::Filter || isa<ArrayType>(Val->getType())) && \"Filter clause has invalid type!\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 4988, __extension__
 __PRETTY_FUNCTION__));
      LP->addClause(cast<Constant>(Val));
    }

    I = LP;
    InstructionList.push_back(I);
    break;
  }

  case bitc::FUNC_CODE_INST_ALLOCA: { // ALLOCA: [instty, opty, op, align]
    if (Record.size() != 4)
      return error("Invalid record");
    using APV = AllocaPackedValues;
    const uint64_t Rec = Record[3];
    const bool InAlloca = Bitfield::get<APV::UsedWithInAlloca>(Rec);
    const bool SwiftError = Bitfield::get<APV::SwiftError>(Rec);
    Type *Ty = getTypeByID(Record[0]);
    if (!Bitfield::get<APV::ExplicitType>(Rec)) {
      auto *PTy = dyn_cast_or_null<PointerType>(Ty);
      if (!PTy)
        return error("Old-style alloca with a non-pointer type");
      Ty = PTy->getPointerElementType();
    }
    Type *OpTy = getTypeByID(Record[1]);
    Value *Size = getFnValueByID(Record[2], OpTy);
    MaybeAlign Align;
    uint64_t AlignExp =
        Bitfield::get<APV::AlignLower>(Rec) |
        (Bitfield::get<APV::AlignUpper>(Rec) << APV::AlignLower::Bits);
    if (Error Err = parseAlignmentValue(AlignExp, Align)) {
      return Err;
    }
    if (!Ty || !Size)
      return error("Invalid record");

    // FIXME: Make this an optional field.
    const DataLayout &DL = TheModule->getDataLayout();
    unsigned AS = DL.getAllocaAddrSpace();

    SmallPtrSet<Type *, 4> Visited;
    if (!Align && !Ty->isSized(&Visited))
      return error("alloca of unsized type");
    if (!Align)
      Align = DL.getPrefTypeAlign(Ty);

    AllocaInst *AI = new AllocaInst(Ty, AS, Size, *Align);
    AI->setUsedWithInAlloca(InAlloca);
    AI->setSwiftError(SwiftError);
    I = AI;
    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_LOAD: { // LOAD: [opty, op, align, vol]
    unsigned OpNum = 0;
    Value *Op;
    if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
        (OpNum + 2 != Record.size() && OpNum + 3 != Record.size()))
      return error("Invalid record");

    if (!isa<PointerType>(Op->getType()))
      return error("Load operand is not a pointer type");

    Type *Ty = nullptr;
    if (OpNum + 3 == Record.size()) {
      Ty = getTypeByID(Record[OpNum++]);
    } else {
      Ty = Op->getType()->getPointerElementType();
    }

    if (Error Err = typeCheckLoadStoreInst(Ty, Op->getType()))
      return Err;

    MaybeAlign Align;
    if (Error Err = parseAlignmentValue(Record[OpNum], Align))
      return Err;
    SmallPtrSet<Type *, 4> Visited;
    if (!Align && !Ty->isSized(&Visited))
      return error("load of unsized type");
    if (!Align)
      Align = TheModule->getDataLayout().getABITypeAlign(Ty);
    I = new LoadInst(Ty, Op, "", Record[OpNum + 1], *Align);
    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_LOADATOMIC: {
     // LOADATOMIC: [opty, op, align, vol, ordering, ssid]
    unsigned OpNum = 0;
    Value *Op;
    if (getValueTypePair(Record, OpNum, NextValueNo, Op) ||
        (OpNum + 4 != Record.size() && OpNum + 5 != Record.size()))
      return error("Invalid record");

    if (!isa<PointerType>(Op->getType()))
      return error("Load operand is not a pointer type");

    Type *Ty = nullptr;
    if (OpNum + 5 == Record.size()) {
      Ty = getTypeByID(Record[OpNum++]);
    } else {
      Ty = Op->getType()->getPointerElementType();
    }

    if (Error Err = typeCheckLoadStoreInst(Ty, Op->getType()))
      return Err;

    AtomicOrdering Ordering = getDecodedOrdering(Record[OpNum + 2]);
    if (Ordering == AtomicOrdering::NotAtomic ||
        Ordering == AtomicOrdering::Release ||
        Ordering == AtomicOrdering::AcquireRelease)
      return error("Invalid record");
    if (Ordering != AtomicOrdering::NotAtomic && Record[OpNum] == 0)
      return error("Invalid record");
    SyncScope::ID SSID = getDecodedSyncScopeID(Record[OpNum + 3]);

    MaybeAlign Align;
    if (Error Err = parseAlignmentValue(Record[OpNum], Align))
      return Err;
    if (!Align)
      return error("Alignment missing from atomic load");
    I = new LoadInst(Ty, Op, "", Record[OpNum + 1], *Align, Ordering, SSID);
    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_STORE:
  case bitc::FUNC_CODE_INST_STORE_OLD: { // STORE2:[ptrty, ptr, val, align, vol]
    unsigned OpNum = 0;
    Value *Val, *Ptr;
    if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
        (BitCode == bitc::FUNC_CODE_INST_STORE
             ? getValueTypePair(Record, OpNum, NextValueNo, Val)
             : popValue(Record, OpNum, NextValueNo,
                        Ptr->getType()->getPointerElementType(), Val)) ||
        OpNum + 2 != Record.size())
      return error("Invalid record");

    if (Error Err = typeCheckLoadStoreInst(Val->getType(), Ptr->getType()))
      return Err;
    MaybeAlign Align;
    if (Error Err = parseAlignmentValue(Record[OpNum], Align))
      return Err;
    SmallPtrSet<Type *, 4> Visited;
    if (!Align && !Val->getType()->isSized(&Visited))
      return error("store of unsized type");
    if (!Align)
      Align = TheModule->getDataLayout().getABITypeAlign(Val->getType());
    I = new StoreInst(Val, Ptr, Record[OpNum + 1], *Align);
    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_STOREATOMIC:
  case bitc::FUNC_CODE_INST_STOREATOMIC_OLD: {
    // STOREATOMIC: [ptrty, ptr, val, align, vol, ordering, ssid]
    unsigned OpNum = 0;
    Value *Val, *Ptr;
    if (getValueTypePair(Record, OpNum, NextValueNo, Ptr) ||
        !isa<PointerType>(Ptr->getType()) ||
        (BitCode == bitc::FUNC_CODE_INST_STOREATOMIC
             ? getValueTypePair(Record, OpNum, NextValueNo, Val)
             : popValue(Record, OpNum, NextValueNo,
                        Ptr->getType()->getPointerElementType(), Val)) ||
        OpNum + 4 != Record.size())
      return error("Invalid record");

    if (Error Err = typeCheckLoadStoreInst(Val->getType(), Ptr->getType()))
      return Err;
    AtomicOrdering Ordering = getDecodedOrdering(Record[OpNum + 2]);
    if (Ordering == AtomicOrdering::NotAtomic ||
        Ordering == AtomicOrdering::Acquire ||
        Ordering == AtomicOrdering::AcquireRelease)
      return error("Invalid record");
    SyncScope::ID SSID = getDecodedSyncScopeID(Record[OpNum + 3]);
    if (Ordering != AtomicOrdering::NotAtomic && Record[OpNum] == 0)
      return error("Invalid record");

    MaybeAlign Align;
    if (Error Err = parseAlignmentValue(Record[OpNum], Align))
      return Err;
    if (!Align)
      return error("Alignment missing from atomic store");
    I = new StoreInst(Val, Ptr, Record[OpNum + 1], *Align, Ordering, SSID);
    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_CMPXCHG_OLD: {
    // CMPXCHG_OLD: [ptrty, ptr, cmp, val, vol, ordering, synchscope,
    // failure_ordering?, weak?]
    const size_t NumRecords = Record.size();
    unsigned OpNum = 0;
    Value *Ptr = nullptr;
    if (getValueTypePair(Record, OpNum, NextValueNo, Ptr))
      return error("Invalid record");

    if (!isa<PointerType>(Ptr->getType()))
      return error("Cmpxchg operand is not a pointer type");

    Value *Cmp = nullptr;
    if (popValue(Record, OpNum, NextValueNo,
                 cast<PointerType>(Ptr->getType())->getPointerElementType(),
                 Cmp))
      return error("Invalid record");

    Value *New = nullptr;
    if (popValue(Record, OpNum, NextValueNo, Cmp->getType(), New) ||
        NumRecords < OpNum + 3 || NumRecords > OpNum + 5)
      return error("Invalid record");

    const AtomicOrdering SuccessOrdering =
        getDecodedOrdering(Record[OpNum + 1]);
    if (SuccessOrdering == AtomicOrdering::NotAtomic ||
        SuccessOrdering == AtomicOrdering::Unordered)
      return error("Invalid record");

    const SyncScope::ID SSID = getDecodedSyncScopeID(Record[OpNum + 2]);

    if (Error Err = typeCheckLoadStoreInst(Cmp->getType(), Ptr->getType()))
      return Err;

    const AtomicOrdering FailureOrdering =
        NumRecords < 7
            ? AtomicCmpXchgInst::getStrongestFailureOrdering(SuccessOrdering)
            : getDecodedOrdering(Record[OpNum + 3]);

    if (FailureOrdering == AtomicOrdering::NotAtomic ||
        FailureOrdering == AtomicOrdering::Unordered)
      return error("Invalid record");

    const Align Alignment(
        TheModule->getDataLayout().getTypeStoreSize(Cmp->getType()));

    I = new AtomicCmpXchgInst(Ptr, Cmp, New, Alignment, SuccessOrdering,
                              FailureOrdering, SSID);
    cast<AtomicCmpXchgInst>(I)->setVolatile(Record[OpNum]);

    if (NumRecords < 8) {
      // Before weak cmpxchgs existed, the instruction simply returned the
      // value loaded from memory, so bitcode files from that era will be
      // expecting the first component of a modern cmpxchg.
      CurBB->getInstList().push_back(I);
      I = ExtractValueInst::Create(I, 0);
    } else {
      cast<AtomicCmpXchgInst>(I)->setWeak(Record[OpNum + 4]);
    }

    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_CMPXCHG: {
    // CMPXCHG: [ptrty, ptr, cmp, val, vol, success_ordering, synchscope,
    // failure_ordering, weak, align?]
    const size_t NumRecords = Record.size();
    unsigned OpNum = 0;
    Value *Ptr = nullptr;
    if (getValueTypePair(Record, OpNum, NextValueNo, Ptr))
      return error("Invalid record");

    if (!isa<PointerType>(Ptr->getType()))
      return error("Cmpxchg operand is not a pointer type");

    Value *Cmp = nullptr;
    if (getValueTypePair(Record, OpNum, NextValueNo, Cmp))
      return error("Invalid record");

    Value *Val = nullptr;
    if (popValue(Record, OpNum, NextValueNo, Cmp->getType(), Val))
      return error("Invalid record");

    if (NumRecords < OpNum + 3 || NumRecords > OpNum + 6)
      return error("Invalid record");

    const bool IsVol = Record[OpNum];

    const AtomicOrdering SuccessOrdering =
        getDecodedOrdering(Record[OpNum + 1]);
    if (!AtomicCmpXchgInst::isValidSuccessOrdering(SuccessOrdering))
      return error("Invalid cmpxchg success ordering");

    const SyncScope::ID SSID = getDecodedSyncScopeID(Record[OpNum + 2]);

    if (Error Err = typeCheckLoadStoreInst(Cmp->getType(), Ptr->getType()))
      return Err;

    const AtomicOrdering FailureOrdering =
        getDecodedOrdering(Record[OpNum + 3]);
    if (!AtomicCmpXchgInst::isValidFailureOrdering(FailureOrdering))
      return error("Invalid cmpxchg failure ordering");

    const bool IsWeak = Record[OpNum + 4];

    MaybeAlign Alignment;

    if (NumRecords == (OpNum + 6)) {
      if (Error Err = parseAlignmentValue(Record[OpNum + 5], Alignment))
        return Err;
    }
    if (!Alignment)
      Alignment =
          Align(TheModule->getDataLayout().getTypeStoreSize(Cmp->getType()));

    I = new AtomicCmpXchgInst(Ptr, Cmp, Val, *Alignment, SuccessOrdering,
                              FailureOrdering, SSID);
    cast<AtomicCmpXchgInst>(I)->setVolatile(IsVol);
    cast<AtomicCmpXchgInst>(I)->setWeak(IsWeak);

    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_ATOMICRMW_OLD:
  case bitc::FUNC_CODE_INST_ATOMICRMW: {
    // ATOMICRMW_OLD: [ptrty, ptr, val, op, vol, ordering, ssid, align?]
    // ATOMICRMW: [ptrty, ptr, valty, val, op, vol, ordering, ssid, align?]
    const size_t NumRecords = Record.size();
    unsigned OpNum = 0;

    Value *Ptr = nullptr;
    if (getValueTypePair(Record, OpNum, NextValueNo, Ptr))
      return error("Invalid record");

    if (!isa<PointerType>(Ptr->getType()))
      return error("Invalid record");

    Value *Val = nullptr;
    if (BitCode == bitc::FUNC_CODE_INST_ATOMICRMW_OLD) {
      if (popValue(Record, OpNum, NextValueNo,
                   cast<PointerType>(Ptr->getType())->getPointerElementType(),
                   Val))
        return error("Invalid record");
    } else {
      if (getValueTypePair(Record, OpNum, NextValueNo, Val))
        return error("Invalid record");
    }

    if (!(NumRecords == (OpNum + 4) || NumRecords == (OpNum + 5)))
      return error("Invalid record");

    const AtomicRMWInst::BinOp Operation =
        getDecodedRMWOperation(Record[OpNum]);
    if (Operation < AtomicRMWInst::FIRST_BINOP ||
        Operation > AtomicRMWInst::LAST_BINOP)
      return error("Invalid record");

    const bool IsVol = Record[OpNum + 1];

    const AtomicOrdering Ordering = getDecodedOrdering(Record[OpNum + 2]);
    if (Ordering == AtomicOrdering::NotAtomic ||
        Ordering == AtomicOrdering::Unordered)
      return error("Invalid record");

    const SyncScope::ID SSID = getDecodedSyncScopeID(Record[OpNum + 3]);

    MaybeAlign Alignment;

    if (NumRecords == (OpNum + 5)) {
      if (Error Err = parseAlignmentValue(Record[OpNum + 4], Alignment))
        return Err;
    }

    if (!Alignment)
      Alignment =
          Align(TheModule->getDataLayout().getTypeStoreSize(Val->getType()));

    I = new AtomicRMWInst(Operation, Ptr, Val, *Alignment, Ordering, SSID);
    cast<AtomicRMWInst>(I)->setVolatile(IsVol);

    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_FENCE: { // FENCE:[ordering, ssid]
    if (2 != Record.size())
      return error("Invalid record");
    AtomicOrdering Ordering = getDecodedOrdering(Record[0]);
    if (Ordering == AtomicOrdering::NotAtomic ||
        Ordering == AtomicOrdering::Unordered ||
        Ordering == AtomicOrdering::Monotonic)
      return error("Invalid record");
    SyncScope::ID SSID = getDecodedSyncScopeID(Record[1]);
    I = new FenceInst(Context, Ordering, SSID);
    InstructionList.push_back(I);
    break;
  }
  case bitc::FUNC_CODE_INST_CALL: {
    // CALL: [paramattrs, cc, fmf, fnty, fnid, arg0, arg1...]
    if (Record.size() < 3)
      return error("Invalid record");

    unsigned OpNum = 0;
    AttributeList PAL = getAttributes(Record[OpNum++]);
    unsigned CCInfo = Record[OpNum++];

    FastMathFlags FMF;
    if ((CCInfo >> bitc::CALL_FMF) & 1) {
      FMF = getDecodedFastMathFlags(Record[OpNum++]);
      if (!FMF.any())
        return error("Fast math flags indicator set for call with no FMF");
    }

    FunctionType *FTy = nullptr;
    if ((CCInfo >> bitc::CALL_EXPLICIT_TYPE) & 1) {
      FTy = dyn_cast<FunctionType>(getTypeByID(Record[OpNum++]));
      if (!FTy)
        return error("Explicit call type is not a function type");
    }

    Value *Callee;
    if (getValueTypePair(Record, OpNum, NextValueNo, Callee))
      return error("Invalid record");

    PointerType *OpTy = dyn_cast<PointerType>(Callee->getType());
    if (!OpTy)
      return error("Callee is not a pointer type");
    if (!FTy) {
      FTy =
          dyn_cast<FunctionType>(Callee->getType()->getPointerElementType());
      if (!FTy)
        return error("Callee is not of pointer to function type");
    } else if (!OpTy->isOpaqueOrPointeeTypeMatches(FTy))
      return error("Explicit call type does not match pointee type of "
                   "callee operand");
    if (Record.size() < FTy->getNumParams() + OpNum)
      return error("Insufficient operands to call");

    SmallVector<Value*, 16> Args;
    SmallVector<Type *, 16> ArgsTys;
    // Read the fixed params.
    for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i, ++OpNum) {
      if (FTy->getParamType(i)->isLabelTy())
        Args.push_back(getBasicBlock(Record[OpNum]));
      else
        Args.push_back(getValue(Record, OpNum, NextValueNo,
                                FTy->getParamType(i)));
      ArgsTys.push_back(FTy->getParamType(i));
      if (!Args.back())
        return error("Invalid record");
    }

    // Read type/value pairs for varargs params.
    if (!FTy->isVarArg()) {
      if (OpNum != Record.size())
        return error("Invalid record");
    } else {
      while (OpNum != Record.size()) {
        Value *Op;
        if (getValueTypePair(Record, OpNum, NextValueNo, Op))
          return error("Invalid record");
        Args.push_back(Op);
        ArgsTys.push_back(Op->getType());
      }
    }

    I = CallInst::Create(FTy, Callee, Args, OperandBundles);
    OperandBundles.clear();
    InstructionList.push_back(I);
    cast<CallInst>(I)->setCallingConv(
        static_cast<CallingConv::ID>((0x7ff & CCInfo) >> bitc::CALL_CCONV));
    CallInst::TailCallKind TCK = CallInst::TCK_None;
    if (CCInfo & 1 << bitc::CALL_TAIL)
      TCK = CallInst::TCK_Tail;
    if (CCInfo & (1 << bitc::CALL_MUSTTAIL))
      TCK = CallInst::TCK_MustTail;
    if (CCInfo & (1 << bitc::CALL_NOTAIL))
      TCK = CallInst::TCK_NoTail;
    cast<CallInst>(I)->setTailCallKind(TCK);
    cast<CallInst>(I)->setAttributes(PAL);
    propagateAttributeTypes(cast<CallBase>(I), ArgsTys);
    if (FMF.any()) {
      if (!isa<FPMathOperator>(I))
        return error("Fast-math-flags specified for call without "
                     "floating-point scalar or vector return type");
      I->setFastMathFlags(FMF);
    }
    break;
  }
  case bitc::FUNC_CODE_INST_VAARG: { // VAARG: [valistty, valist, instty]
    if (Record.size() < 3)
      return error("Invalid record");
    Type *OpTy = getTypeByID(Record[0]);
    Value *Op = getValue(Record, 1, NextValueNo, OpTy);
    Type *ResTy = getTypeByID(Record[2]);
    if (!OpTy || !Op || !ResTy)
      return error("Invalid record");
    I = new VAArgInst(Op, ResTy);
    InstructionList.push_back(I);
    break;
  }

  case bitc::FUNC_CODE_OPERAND_BUNDLE: {
    // A call or an invoke can be optionally prefixed with some variable
    // number of operand bundle blocks.  These blocks are read into
    // OperandBundles and consumed at the next call or invoke instruction.

    if (Record.empty() || Record[0] >= BundleTags.size())
      return error("Invalid record");

    std::vector<Value *> Inputs;

    unsigned OpNum = 1;
    while (OpNum != Record.size()) {
      Value *Op;
      if (getValueTypePair(Record, OpNum, NextValueNo, Op))
        return error("Invalid record");
      Inputs.push_back(Op);
    }

    OperandBundles.emplace_back(BundleTags[Record[0]], std::move(Inputs));
    continue;
  }

  case bitc::FUNC_CODE_INST_FREEZE: { // FREEZE: [opty,opval]
    unsigned OpNum = 0;
    Value *Op = nullptr;
    if (getValueTypePair(Record, OpNum, NextValueNo, Op))
      return error("Invalid record");
    if (OpNum != Record.size())
      return error("Invalid record");

    I = new FreezeInst(Op);
    InstructionList.push_back(I);
    break;
  }
  }

  // Add instruction to end of current BB.  If there is no current BB, reject
  // this file.
  if (!CurBB) {
    I->deleteValue();
    return error("Invalid instruction with no BB");
  }
  if (!OperandBundles.empty()) {
    I->deleteValue();
    return error("Operand bundles found with no consumer");
  }
  CurBB->getInstList().push_back(I);

  // If this was a terminator instruction, move to the next block.
  if (I->isTerminator()) {
    ++CurBBNo;
    CurBB = CurBBNo < FunctionBBs.size() ? FunctionBBs[CurBBNo] : nullptr;
  }

  // Non-void values get registered in the value table for future use.
  if (!I->getType()->isVoidTy())
    ValueList.assignValue(I, NextValueNo++);
}

5531OutOfRecordLoop:

if (!OperandBundles.empty())
  return error("Operand bundles found with no consumer");

// Check the function list for unresolved values.
if (Argument *A = dyn_cast<Argument>(ValueList.back())) {
  if (!A->getParent()) {
    // We found at least one unresolved value.  Nuke them all to avoid leaks.
    for (unsigned i = ModuleValueListSize, e = ValueList.size(); i != e; ++i){
      if ((A = dyn_cast_or_null<Argument>(ValueList[i])) && !A->getParent()) {
        A->replaceAllUsesWith(UndefValue::get(A->getType()));
        delete A;
      }
    }
    return error("Never resolved value found in function");
  }
}

// Unexpected unresolved metadata about to be dropped.
if (MDLoader->hasFwdRefs())
  return error("Invalid function metadata: outgoing forward refs");

// Trim the value list down to the size it was before we parsed this function.
ValueList.shrinkTo(ModuleValueListSize);
MDLoader->shrinkTo(ModuleMDLoaderSize);
std::vector<BasicBlock*>().swap(FunctionBBs);
return Error::success();
5559}

5561/// Find the function body in the bitcode stream
5562Error BitcodeReader::findFunctionInStream(
  Function *F,
  DenseMap<Function *, uint64_t>::iterator DeferredFunctionInfoIterator) {
while (DeferredFunctionInfoIterator->second == 0) {
  // This is the fallback handling for the old format bitcode that
  // didn't contain the function index in the VST, or when we have
  // an anonymous function which would not have a VST entry.
  // Assert that we have one of those two cases.
  assert(VSTOffset == 0 || !F->hasName())(static_cast <bool> (VSTOffset == 0 || !F->hasName()
) ? void (0) : __assert_fail ("VSTOffset == 0 || !F->hasName()"
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5570, __extension__
 __PRETTY_FUNCTION__));
  // Parse the next body in the stream and set its position in the
  // DeferredFunctionInfo map.
  if (Error Err = rememberAndSkipFunctionBodies())
    return Err;
}
return Error::success();
5577}

5579SyncScope::ID BitcodeReader::getDecodedSyncScopeID(unsigned Val) {
if (Val == SyncScope::SingleThread || Val == SyncScope::System)
  return SyncScope::ID(Val);
if (Val >= SSIDs.size())
  return SyncScope::System; // Map unknown synchronization scopes to system.
return SSIDs[Val];
5585}

5587//===----------------------------------------------------------------------===//
5588// GVMaterializer implementation
5589//===----------------------------------------------------------------------===//

5591Error BitcodeReader::materialize(GlobalValue *GV) {
Function *F = dyn_cast<Function>(GV);
// If it's not a function or is already material, ignore the request.
if (!F || !F->isMaterializable())
  return Error::success();

DenseMap<Function*, uint64_t>::iterator DFII = DeferredFunctionInfo.find(F);
assert(DFII != DeferredFunctionInfo.end() && "Deferred function not found!")(static_cast <bool> (DFII != DeferredFunctionInfo.end()
 && "Deferred function not found!") ? void (0) : __assert_fail
 ("DFII != DeferredFunctionInfo.end() && \"Deferred function not found!\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5598, __extension__
 __PRETTY_FUNCTION__));
// If its position is recorded as 0, its body is somewhere in the stream
// but we haven't seen it yet.
if (DFII->second == 0)
  if (Error Err = findFunctionInStream(F, DFII))
    return Err;

// Materialize metadata before parsing any function bodies.
if (Error Err = materializeMetadata())
  return Err;

// Move the bit stream to the saved position of the deferred function body.
if (Error JumpFailed = Stream.JumpToBit(DFII->second))
  return JumpFailed;
if (Error Err = parseFunctionBody(F))
  return Err;
F->setIsMaterializable(false);

if (StripDebugInfo)
  stripDebugInfo(*F);

// Upgrade any old intrinsic calls in the function.
for (auto &I : UpgradedIntrinsics) {
  for (User *U : llvm::make_early_inc_range(I.first->materialized_users()))
    if (CallInst *CI = dyn_cast<CallInst>(U))
      UpgradeIntrinsicCall(CI, I.second);
}

// Update calls to the remangled intrinsics
for (auto &I : RemangledIntrinsics)
  for (User *U : llvm::make_early_inc_range(I.first->materialized_users()))
    // Don't expect any other users than call sites
    cast<CallBase>(U)->setCalledFunction(I.second);

// Finish fn->subprogram upgrade for materialized functions.
if (DISubprogram *SP = MDLoader->lookupSubprogramForFunction(F))
  F->setSubprogram(SP);

// Check if the TBAA Metadata are valid, otherwise we will need to strip them.
if (!MDLoader->isStrippingTBAA()) {
  for (auto &I : instructions(F)) {
    MDNode *TBAA = I.getMetadata(LLVMContext::MD_tbaa);
    if (!TBAA || TBAAVerifyHelper.visitTBAAMetadata(I, TBAA))
      continue;
    MDLoader->setStripTBAA(true);
    stripTBAA(F->getParent());
  }
}

for (auto &I : instructions(F)) {
  // "Upgrade" older incorrect branch weights by dropping them.
  if (auto *MD = I.getMetadata(LLVMContext::MD_prof)) {
    if (MD->getOperand(0) != nullptr && isa<MDString>(MD->getOperand(0))) {
      MDString *MDS = cast<MDString>(MD->getOperand(0));
      StringRef ProfName = MDS->getString();
      // Check consistency of !prof branch_weights metadata.
      if (!ProfName.equals("branch_weights"))
        continue;
      unsigned ExpectedNumOperands = 0;
      if (BranchInst *BI = dyn_cast<BranchInst>(&I))
        ExpectedNumOperands = BI->getNumSuccessors();
      else if (SwitchInst *SI = dyn_cast<SwitchInst>(&I))
        ExpectedNumOperands = SI->getNumSuccessors();
      else if (isa<CallInst>(&I))
        ExpectedNumOperands = 1;
      else if (IndirectBrInst *IBI = dyn_cast<IndirectBrInst>(&I))
        ExpectedNumOperands = IBI->getNumDestinations();
      else if (isa<SelectInst>(&I))
        ExpectedNumOperands = 2;
      else
        continue; // ignore and continue.

      // If branch weight doesn't match, just strip branch weight.
      if (MD->getNumOperands() != 1 + ExpectedNumOperands)
        I.setMetadata(LLVMContext::MD_prof, nullptr);
    }
  }

  // Remove incompatible attributes on function calls.
  if (auto *CI = dyn_cast<CallBase>(&I)) {
    CI->removeRetAttrs(AttributeFuncs::typeIncompatible(
        CI->getFunctionType()->getReturnType()));

    for (unsigned ArgNo = 0; ArgNo < CI->arg_size(); ++ArgNo)
      CI->removeParamAttrs(ArgNo, AttributeFuncs::typeIncompatible(
                                      CI->getArgOperand(ArgNo)->getType()));
  }
}

// Look for functions that rely on old function attribute behavior.
UpgradeFunctionAttributes(*F);

// Bring in any functions that this function forward-referenced via
// blockaddresses.
return materializeForwardReferencedFunctions();
5693}

5695Error BitcodeReader::materializeModule() {
if (Error Err = materializeMetadata())
  return Err;

// Promise to materialize all forward references.
WillMaterializeAllForwardRefs = true;

// Iterate over the module, deserializing any functions that are still on
// disk.
for (Function &F : *TheModule) {
  if (Error Err = materialize(&F))
    return Err;
}
// At this point, if there are any function bodies, parse the rest of
// the bits in the module past the last function block we have recorded
// through either lazy scanning or the VST.
if (LastFunctionBlockBit || NextUnreadBit)
  if (Error Err = parseModule(LastFunctionBlockBit > NextUnreadBit
                                  ? LastFunctionBlockBit
                                  : NextUnreadBit))
    return Err;

// Check that all block address forward references got resolved (as we
// promised above).
if (!BasicBlockFwdRefs.empty())
  return error("Never resolved function from blockaddress");

// Upgrade any intrinsic calls that slipped through (should not happen!) and
// delete the old functions to clean up. We can't do this unless the entire
// module is materialized because there could always be another function body
// with calls to the old function.
for (auto &I : UpgradedIntrinsics) {
  for (auto *U : I.first->users()) {
    if (CallInst *CI = dyn_cast<CallInst>(U))
      UpgradeIntrinsicCall(CI, I.second);
  }
  if (!I.first->use_empty())
    I.first->replaceAllUsesWith(I.second);
  I.first->eraseFromParent();
}
UpgradedIntrinsics.clear();
// Do the same for remangled intrinsics
for (auto &I : RemangledIntrinsics) {
  I.first->replaceAllUsesWith(I.second);
  I.first->eraseFromParent();
}
RemangledIntrinsics.clear();

UpgradeDebugInfo(*TheModule);

UpgradeModuleFlags(*TheModule);

UpgradeARCRuntime(*TheModule);

return Error::success();
5750}

5752std::vector<StructType *> BitcodeReader::getIdentifiedStructTypes() const {
return IdentifiedStructTypes;
5754}

5756ModuleSummaryIndexBitcodeReader::ModuleSummaryIndexBitcodeReader(
  BitstreamCursor Cursor, StringRef Strtab, ModuleSummaryIndex &TheIndex,
  StringRef ModulePath, unsigned ModuleId)
  : BitcodeReaderBase(std::move(Cursor), Strtab), TheIndex(TheIndex),
    ModulePath(ModulePath), ModuleId(ModuleId) {}

5762void ModuleSummaryIndexBitcodeReader::addThisModule() {
TheIndex.addModule(ModulePath, ModuleId);
5764}

5766ModuleSummaryIndex::ModuleInfo *
5767ModuleSummaryIndexBitcodeReader::getThisModule() {
return TheIndex.getModule(ModulePath);
5769}

5771std::pair<ValueInfo, GlobalValue::GUID>
5772ModuleSummaryIndexBitcodeReader::getValueInfoFromValueId(unsigned ValueId) {
auto VGI = ValueIdToValueInfoMap[ValueId];
assert(VGI.first)(static_cast <bool> (VGI.first) ? void (0) : __assert_fail
 ("VGI.first", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5774
, __extension__ __PRETTY_FUNCTION__));
return VGI;
5776}

5778void ModuleSummaryIndexBitcodeReader::setValueGUID(
  uint64_t ValueID, StringRef ValueName, GlobalValue::LinkageTypes Linkage,
  StringRef SourceFileName) {
std::string GlobalId =
    GlobalValue::getGlobalIdentifier(ValueName, Linkage, SourceFileName);
auto ValueGUID = GlobalValue::getGUID(GlobalId);
auto OriginalNameID = ValueGUID;
if (GlobalValue::isLocalLinkage(Linkage))
  OriginalNameID = GlobalValue::getGUID(ValueName);
if (PrintSummaryGUIDs)
  dbgs() << "GUID " << ValueGUID << "(" << OriginalNameID << ") is "
         << ValueName << "\n";

// UseStrtab is false for legacy summary formats and value names are
// created on stack. In that case we save the name in a string saver in
// the index so that the value name can be recorded.
ValueIdToValueInfoMap[ValueID] = std::make_pair(
    TheIndex.getOrInsertValueInfo(
        ValueGUID,
        UseStrtab ? ValueName : TheIndex.saveString(ValueName)),
    OriginalNameID);
5799}

5801// Specialized value symbol table parser used when reading module index
5802// blocks where we don't actually create global values. The parsed information
5803// is saved in the bitcode reader for use when later parsing summaries.
5804Error ModuleSummaryIndexBitcodeReader::parseValueSymbolTable(
  uint64_t Offset,
  DenseMap<unsigned, GlobalValue::LinkageTypes> &ValueIdToLinkageMap) {
// With a strtab the VST is not required to parse the summary.
if (UseStrtab)
  return Error::success();

assert(Offset > 0 && "Expected non-zero VST offset")(static_cast <bool> (Offset > 0 && "Expected non-zero VST offset"
) ? void (0) : __assert_fail ("Offset > 0 && \"Expected non-zero VST offset\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5811, __extension__
 __PRETTY_FUNCTION__));
Expected<uint64_t> MaybeCurrentBit = jumpToValueSymbolTable(Offset, Stream);
if (!MaybeCurrentBit)
  return MaybeCurrentBit.takeError();
uint64_t CurrentBit = MaybeCurrentBit.get();

if (Error Err = Stream.EnterSubBlock(bitc::VALUE_SYMTAB_BLOCK_ID))
  return Err;

SmallVector<uint64_t, 64> Record;

// Read all the records for this value table.
SmallString<128> ValueName;

while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    // Done parsing VST, jump back to wherever we came from.
    if (Error JumpFailed = Stream.JumpToBit(CurrentBit))
      return JumpFailed;
    return Error::success();
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Read a record.
  Record.clear();
  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  switch (MaybeRecord.get()) {
  default: // Default behavior: ignore (e.g. VST_CODE_BBENTRY records).
    break;
  case bitc::VST_CODE_ENTRY: { // VST_CODE_ENTRY: [valueid, namechar x N]
    if (convertToString(Record, 1, ValueName))
      return error("Invalid record");
    unsigned ValueID = Record[0];
    assert(!SourceFileName.empty())(static_cast <bool> (!SourceFileName.empty()) ? void (0
) : __assert_fail ("!SourceFileName.empty()", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 5857, __extension__ __PRETTY_FUNCTION__));
    auto VLI = ValueIdToLinkageMap.find(ValueID);
    assert(VLI != ValueIdToLinkageMap.end() &&(static_cast <bool> (VLI != ValueIdToLinkageMap.end() &&
 "No linkage found for VST entry?") ? void (0) : __assert_fail
 ("VLI != ValueIdToLinkageMap.end() && \"No linkage found for VST entry?\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5860, __extension__
 __PRETTY_FUNCTION__))
           "No linkage found for VST entry?")(static_cast <bool> (VLI != ValueIdToLinkageMap.end() &&
 "No linkage found for VST entry?") ? void (0) : __assert_fail
 ("VLI != ValueIdToLinkageMap.end() && \"No linkage found for VST entry?\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5860, __extension__
 __PRETTY_FUNCTION__));
    auto Linkage = VLI->second;
    setValueGUID(ValueID, ValueName, Linkage, SourceFileName);
    ValueName.clear();
    break;
  }
  case bitc::VST_CODE_FNENTRY: {
    // VST_CODE_FNENTRY: [valueid, offset, namechar x N]
    if (convertToString(Record, 2, ValueName))
      return error("Invalid record");
    unsigned ValueID = Record[0];
    assert(!SourceFileName.empty())(static_cast <bool> (!SourceFileName.empty()) ? void (0
) : __assert_fail ("!SourceFileName.empty()", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 5871, __extension__ __PRETTY_FUNCTION__));
    auto VLI = ValueIdToLinkageMap.find(ValueID);
    assert(VLI != ValueIdToLinkageMap.end() &&(static_cast <bool> (VLI != ValueIdToLinkageMap.end() &&
 "No linkage found for VST entry?") ? void (0) : __assert_fail
 ("VLI != ValueIdToLinkageMap.end() && \"No linkage found for VST entry?\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5874, __extension__
 __PRETTY_FUNCTION__))
           "No linkage found for VST entry?")(static_cast <bool> (VLI != ValueIdToLinkageMap.end() &&
 "No linkage found for VST entry?") ? void (0) : __assert_fail
 ("VLI != ValueIdToLinkageMap.end() && \"No linkage found for VST entry?\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5874, __extension__
 __PRETTY_FUNCTION__));
    auto Linkage = VLI->second;
    setValueGUID(ValueID, ValueName, Linkage, SourceFileName);
    ValueName.clear();
    break;
  }
  case bitc::VST_CODE_COMBINED_ENTRY: {
    // VST_CODE_COMBINED_ENTRY: [valueid, refguid]
    unsigned ValueID = Record[0];
    GlobalValue::GUID RefGUID = Record[1];
    // The "original name", which is the second value of the pair will be
    // overriden later by a FS_COMBINED_ORIGINAL_NAME in the combined index.
    ValueIdToValueInfoMap[ValueID] =
        std::make_pair(TheIndex.getOrInsertValueInfo(RefGUID), RefGUID);
    break;
  }
  }
}
5892}

5894// Parse just the blocks needed for building the index out of the module.
5895// At the end of this routine the module Index is populated with a map
5896// from global value id to GlobalValueSummary objects.
5897Error ModuleSummaryIndexBitcodeReader::parseModule() {
if (Error Err = Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
  return Err;

SmallVector<uint64_t, 64> Record;
DenseMap<unsigned, GlobalValue::LinkageTypes> ValueIdToLinkageMap;
unsigned ValueId = 0;

// Read the index for this module.
while (true) {
  Expected<llvm::BitstreamEntry> MaybeEntry = Stream.advance();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  llvm::BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return Error::success();

  case BitstreamEntry::SubBlock:
    switch (Entry.ID) {
    default: // Skip unknown content.
      if (Error Err = Stream.SkipBlock())
        return Err;
      break;
    case bitc::BLOCKINFO_BLOCK_ID:
      // Need to parse these to get abbrev ids (e.g. for VST)
      if (Error Err = readBlockInfo())
        return Err;
      break;
    case bitc::VALUE_SYMTAB_BLOCK_ID:
      // Should have been parsed earlier via VSTOffset, unless there
      // is no summary section.
      assert(((SeenValueSymbolTable && VSTOffset > 0) ||(static_cast <bool> (((SeenValueSymbolTable && VSTOffset
 > 0) || !SeenGlobalValSummary) && "Expected early VST parse via VSTOffset record"
) ? void (0) : __assert_fail ("((SeenValueSymbolTable && VSTOffset > 0) || !SeenGlobalValSummary) && \"Expected early VST parse via VSTOffset record\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5934, __extension__
 __PRETTY_FUNCTION__))
              !SeenGlobalValSummary) &&(static_cast <bool> (((SeenValueSymbolTable && VSTOffset
 > 0) || !SeenGlobalValSummary) && "Expected early VST parse via VSTOffset record"
) ? void (0) : __assert_fail ("((SeenValueSymbolTable && VSTOffset > 0) || !SeenGlobalValSummary) && \"Expected early VST parse via VSTOffset record\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5934, __extension__
 __PRETTY_FUNCTION__))
             "Expected early VST parse via VSTOffset record")(static_cast <bool> (((SeenValueSymbolTable && VSTOffset
 > 0) || !SeenGlobalValSummary) && "Expected early VST parse via VSTOffset record"
) ? void (0) : __assert_fail ("((SeenValueSymbolTable && VSTOffset > 0) || !SeenGlobalValSummary) && \"Expected early VST parse via VSTOffset record\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5934, __extension__
 __PRETTY_FUNCTION__));
      if (Error Err = Stream.SkipBlock())
        return Err;
      break;
    case bitc::GLOBALVAL_SUMMARY_BLOCK_ID:
    case bitc::FULL_LTO_GLOBALVAL_SUMMARY_BLOCK_ID:
      // Add the module if it is a per-module index (has a source file name).
      if (!SourceFileName.empty())
        addThisModule();
      assert(!SeenValueSymbolTable &&(static_cast <bool> (!SeenValueSymbolTable && "Already read VST when parsing summary block?"
) ? void (0) : __assert_fail ("!SeenValueSymbolTable && \"Already read VST when parsing summary block?\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5944, __extension__
 __PRETTY_FUNCTION__))
             "Already read VST when parsing summary block?")(static_cast <bool> (!SeenValueSymbolTable && "Already read VST when parsing summary block?"
) ? void (0) : __assert_fail ("!SeenValueSymbolTable && \"Already read VST when parsing summary block?\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5944, __extension__
 __PRETTY_FUNCTION__));
      // We might not have a VST if there were no values in the
      // summary. An empty summary block generated when we are
      // performing ThinLTO compiles so we don't later invoke
      // the regular LTO process on them.
      if (VSTOffset > 0) {
        if (Error Err = parseValueSymbolTable(VSTOffset, ValueIdToLinkageMap))
          return Err;
        SeenValueSymbolTable = true;
      }
      SeenGlobalValSummary = true;
      if (Error Err = parseEntireSummary(Entry.ID))
        return Err;
      break;
    case bitc::MODULE_STRTAB_BLOCK_ID:
      if (Error Err = parseModuleStringTable())
        return Err;
      break;
    }
    continue;

  case BitstreamEntry::Record: {
      Record.clear();
      Expected<unsigned> MaybeBitCode = Stream.readRecord(Entry.ID, Record);
      if (!MaybeBitCode)
        return MaybeBitCode.takeError();
      switch (MaybeBitCode.get()) {
      default:
        break; // Default behavior, ignore unknown content.
      case bitc::MODULE_CODE_VERSION: {
        if (Error Err = parseVersionRecord(Record).takeError())
          return Err;
        break;
      }
      /// MODULE_CODE_SOURCE_FILENAME: [namechar x N]
      case bitc::MODULE_CODE_SOURCE_FILENAME: {
        SmallString<128> ValueName;
        if (convertToString(Record, 0, ValueName))
          return error("Invalid record");
        SourceFileName = ValueName.c_str();
        break;
      }
      /// MODULE_CODE_HASH: [5*i32]
      case bitc::MODULE_CODE_HASH: {
        if (Record.size() != 5)
          return error("Invalid hash length " + Twine(Record.size()).str());
        auto &Hash = getThisModule()->second.second;
        int Pos = 0;
        for (auto &Val : Record) {
          assert(!(Val >> 32) && "Unexpected high bits set")(static_cast <bool> (!(Val >> 32) && "Unexpected high bits set"
) ? void (0) : __assert_fail ("!(Val >> 32) && \"Unexpected high bits set\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 5993, __extension__
 __PRETTY_FUNCTION__));
          Hash[Pos++] = Val;
        }
        break;
      }
      /// MODULE_CODE_VSTOFFSET: [offset]
      case bitc::MODULE_CODE_VSTOFFSET:
        if (Record.empty())
          return error("Invalid record");
        // Note that we subtract 1 here because the offset is relative to one
        // word before the start of the identification or module block, which
        // was historically always the start of the regular bitcode header.
        VSTOffset = Record[0] - 1;
        break;
      // v1 GLOBALVAR: [pointer type, isconst,     initid,       linkage, ...]
      // v1 FUNCTION:  [type,         callingconv, isproto,      linkage, ...]
      // v1 ALIAS:     [alias type,   addrspace,   aliasee val#, linkage, ...]
      // v2: [strtab offset, strtab size, v1]
      case bitc::MODULE_CODE_GLOBALVAR:
      case bitc::MODULE_CODE_FUNCTION:
      case bitc::MODULE_CODE_ALIAS: {
        StringRef Name;
        ArrayRef<uint64_t> GVRecord;
        std::tie(Name, GVRecord) = readNameFromStrtab(Record);
        if (GVRecord.size() <= 3)
          return error("Invalid record");
        uint64_t RawLinkage = GVRecord[3];
        GlobalValue::LinkageTypes Linkage = getDecodedLinkage(RawLinkage);
        if (!UseStrtab) {
          ValueIdToLinkageMap[ValueId++] = Linkage;
          break;
        }

        setValueGUID(ValueId++, Name, Linkage, SourceFileName);
        break;
      }
      }
    }
    continue;
  }
}
6034}

6036std::vector<ValueInfo>
6037ModuleSummaryIndexBitcodeReader::makeRefList(ArrayRef<uint64_t> Record) {
std::vector<ValueInfo> Ret;
Ret.reserve(Record.size());
for (uint64_t RefValueId : Record)
  Ret.push_back(getValueInfoFromValueId(RefValueId).first);
return Ret;
6043}

6045std::vector<FunctionSummary::EdgeTy>
6046ModuleSummaryIndexBitcodeReader::makeCallList(ArrayRef<uint64_t> Record,
                                            bool IsOldProfileFormat,
                                            bool HasProfile, bool HasRelBF) {
std::vector<FunctionSummary::EdgeTy> Ret;
Ret.reserve(Record.size());
for (unsigned I = 0, E = Record.size(); I != E; ++I) {
  CalleeInfo::HotnessType Hotness = CalleeInfo::HotnessType::Unknown;
  uint64_t RelBF = 0;
  ValueInfo Callee = getValueInfoFromValueId(Record[I]).first;
  if (IsOldProfileFormat) {
    I += 1; // Skip old callsitecount field
    if (HasProfile)
      I += 1; // Skip old profilecount field
  } else if (HasProfile)
    Hotness = static_cast<CalleeInfo::HotnessType>(Record[++I]);
  else if (HasRelBF)
    RelBF = Record[++I];
  Ret.push_back(FunctionSummary::EdgeTy{Callee, CalleeInfo(Hotness, RelBF)});
}
return Ret;
6066}

6068static void
6069parseWholeProgramDevirtResolutionByArg(ArrayRef<uint64_t> Record, size_t &Slot,
                                     WholeProgramDevirtResolution &Wpd) {
uint64_t ArgNum = Record[Slot++];
WholeProgramDevirtResolution::ByArg &B =
    Wpd.ResByArg[{Record.begin() + Slot, Record.begin() + Slot + ArgNum}];
Slot += ArgNum;

B.TheKind =
    static_cast<WholeProgramDevirtResolution::ByArg::Kind>(Record[Slot++]);
B.Info = Record[Slot++];
B.Byte = Record[Slot++];
B.Bit = Record[Slot++];
6081}

6083static void parseWholeProgramDevirtResolution(ArrayRef<uint64_t> Record,
                                            StringRef Strtab, size_t &Slot,
                                            TypeIdSummary &TypeId) {
uint64_t Id = Record[Slot++];
WholeProgramDevirtResolution &Wpd = TypeId.WPDRes[Id];

Wpd.TheKind = static_cast<WholeProgramDevirtResolution::Kind>(Record[Slot++]);
Wpd.SingleImplName = {Strtab.data() + Record[Slot],
                      static_cast<size_t>(Record[Slot + 1])};
Slot += 2;

uint64_t ResByArgNum = Record[Slot++];
for (uint64_t I = 0; I != ResByArgNum; ++I)
  parseWholeProgramDevirtResolutionByArg(Record, Slot, Wpd);
6097}

6099static void parseTypeIdSummaryRecord(ArrayRef<uint64_t> Record,
                                   StringRef Strtab,
                                   ModuleSummaryIndex &TheIndex) {
size_t Slot = 0;
TypeIdSummary &TypeId = TheIndex.getOrInsertTypeIdSummary(
    {Strtab.data() + Record[Slot], static_cast<size_t>(Record[Slot + 1])});
Slot += 2;

TypeId.TTRes.TheKind = static_cast<TypeTestResolution::Kind>(Record[Slot++]);
TypeId.TTRes.SizeM1BitWidth = Record[Slot++];
TypeId.TTRes.AlignLog2 = Record[Slot++];
TypeId.TTRes.SizeM1 = Record[Slot++];
TypeId.TTRes.BitMask = Record[Slot++];
TypeId.TTRes.InlineBits = Record[Slot++];

while (Slot < Record.size())
  parseWholeProgramDevirtResolution(Record, Strtab, Slot, TypeId);
6116}

6118std::vector<FunctionSummary::ParamAccess>
6119ModuleSummaryIndexBitcodeReader::parseParamAccesses(ArrayRef<uint64_t> Record) {
auto ReadRange = [&]() {
  APInt Lower(FunctionSummary::ParamAccess::RangeWidth,
              BitcodeReader::decodeSignRotatedValue(Record.front()));
  Record = Record.drop_front();
  APInt Upper(FunctionSummary::ParamAccess::RangeWidth,
              BitcodeReader::decodeSignRotatedValue(Record.front()));
  Record = Record.drop_front();
  ConstantRange Range{Lower, Upper};
  assert(!Range.isFullSet())(static_cast <bool> (!Range.isFullSet()) ? void (0) : __assert_fail
 ("!Range.isFullSet()", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 6128, __extension__ __PRETTY_FUNCTION__));
  assert(!Range.isUpperSignWrapped())(static_cast <bool> (!Range.isUpperSignWrapped()) ? void
 (0) : __assert_fail ("!Range.isUpperSignWrapped()", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 6129, __extension__ __PRETTY_FUNCTION__));
  return Range;
};

std::vector<FunctionSummary::ParamAccess> PendingParamAccesses;
while (!Record.empty()) {
  PendingParamAccesses.emplace_back();
  FunctionSummary::ParamAccess &ParamAccess = PendingParamAccesses.back();
  ParamAccess.ParamNo = Record.front();
  Record = Record.drop_front();
  ParamAccess.Use = ReadRange();
  ParamAccess.Calls.resize(Record.front());
  Record = Record.drop_front();
  for (auto &Call : ParamAccess.Calls) {
    Call.ParamNo = Record.front();
    Record = Record.drop_front();
    Call.Callee = getValueInfoFromValueId(Record.front()).first;
    Record = Record.drop_front();
    Call.Offsets = ReadRange();
  }
}
return PendingParamAccesses;
6151}

6153void ModuleSummaryIndexBitcodeReader::parseTypeIdCompatibleVtableInfo(
  ArrayRef<uint64_t> Record, size_t &Slot,
  TypeIdCompatibleVtableInfo &TypeId) {
uint64_t Offset = Record[Slot++];
ValueInfo Callee = getValueInfoFromValueId(Record[Slot++]).first;
TypeId.push_back({Offset, Callee});
6159}

6161void ModuleSummaryIndexBitcodeReader::parseTypeIdCompatibleVtableSummaryRecord(
  ArrayRef<uint64_t> Record) {
size_t Slot = 0;
TypeIdCompatibleVtableInfo &TypeId =
    TheIndex.getOrInsertTypeIdCompatibleVtableSummary(
        {Strtab.data() + Record[Slot],
         static_cast<size_t>(Record[Slot + 1])});
Slot += 2;

while (Slot < Record.size())
  parseTypeIdCompatibleVtableInfo(Record, Slot, TypeId);
6172}

6174static void setSpecialRefs(std::vector<ValueInfo> &Refs, unsigned ROCnt,
                         unsigned WOCnt) {
// Readonly and writeonly refs are in the end of the refs list.
assert(ROCnt + WOCnt <= Refs.size())(static_cast <bool> (ROCnt + WOCnt <= Refs.size()) ?
 void (0) : __assert_fail ("ROCnt + WOCnt <= Refs.size()",
 "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 6177, __extension__
 __PRETTY_FUNCTION__));
unsigned FirstWORef = Refs.size() - WOCnt;
unsigned RefNo = FirstWORef - ROCnt;
for (; RefNo < FirstWORef; ++RefNo)
  Refs[RefNo].setReadOnly();
for (; RefNo < Refs.size(); ++RefNo)
  Refs[RefNo].setWriteOnly();
6184}

6186// Eagerly parse the entire summary block. This populates the GlobalValueSummary
6187// objects in the index.
6188Error ModuleSummaryIndexBitcodeReader::parseEntireSummary(unsigned ID) {
if (Error Err = Stream.EnterSubBlock(ID))
  return Err;
SmallVector<uint64_t, 64> Record;

// Parse version
{
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  if (Entry.Kind != BitstreamEntry::Record)
    return error("Invalid Summary Block: record for version expected");
  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  if (MaybeRecord.get() != bitc::FS_VERSION)
    return error("Invalid Summary Block: version expected");
}
const uint64_t Version = Record[0];
const bool IsOldProfileFormat = Version == 1;
if (Version < 1 || Version > ModuleSummaryIndex::BitcodeSummaryVersion)
  return error("Invalid summary version " + Twine(Version) +
               ". Version should be in the range [1-" +
               Twine(ModuleSummaryIndex::BitcodeSummaryVersion) +
               "].");
Record.clear();

// Keep around the last seen summary to be used when we see an optional
// "OriginalName" attachement.
GlobalValueSummary *LastSeenSummary = nullptr;
GlobalValue::GUID LastSeenGUID = 0;

// We can expect to see any number of type ID information records before
// each function summary records; these variables store the information
// collected so far so that it can be used to create the summary object.
std::vector<GlobalValue::GUID> PendingTypeTests;
std::vector<FunctionSummary::VFuncId> PendingTypeTestAssumeVCalls,
    PendingTypeCheckedLoadVCalls;
std::vector<FunctionSummary::ConstVCall> PendingTypeTestAssumeConstVCalls,
    PendingTypeCheckedLoadConstVCalls;
std::vector<FunctionSummary::ParamAccess> PendingParamAccesses;

while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return Error::success();
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Read a record. The record format depends on whether this
  // is a per-module index or a combined index file. In the per-module
  // case the records contain the associated value's ID for correlation
  // with VST entries. In the combined index the correlation is done
  // via the bitcode offset of the summary records (which were saved
  // in the combined index VST entries). The records also contain
  // information used for ThinLTO renaming and importing.
  Record.clear();
  Expected<unsigned> MaybeBitCode = Stream.readRecord(Entry.ID, Record);
  if (!MaybeBitCode)
    return MaybeBitCode.takeError();
  switch (unsigned BitCode = MaybeBitCode.get()) {
  default: // Default behavior: ignore.
    break;
  case bitc::FS_FLAGS: {  // [flags]
    TheIndex.setFlags(Record[0]);
    break;
  }
  case bitc::FS_VALUE_GUID: { // [valueid, refguid]
    uint64_t ValueID = Record[0];
    GlobalValue::GUID RefGUID = Record[1];
    ValueIdToValueInfoMap[ValueID] =
        std::make_pair(TheIndex.getOrInsertValueInfo(RefGUID), RefGUID);
    break;
  }
  // FS_PERMODULE: [valueid, flags, instcount, fflags, numrefs,
  //                numrefs x valueid, n x (valueid)]
  // FS_PERMODULE_PROFILE: [valueid, flags, instcount, fflags, numrefs,
  //                        numrefs x valueid,
  //                        n x (valueid, hotness)]
  // FS_PERMODULE_RELBF: [valueid, flags, instcount, fflags, numrefs,
  //                      numrefs x valueid,
  //                      n x (valueid, relblockfreq)]
  case bitc::FS_PERMODULE:
  case bitc::FS_PERMODULE_RELBF:
  case bitc::FS_PERMODULE_PROFILE: {
    unsigned ValueID = Record[0];
    uint64_t RawFlags = Record[1];
    unsigned InstCount = Record[2];
    uint64_t RawFunFlags = 0;
    unsigned NumRefs = Record[3];
    unsigned NumRORefs = 0, NumWORefs = 0;
    int RefListStartIndex = 4;
    if (Version >= 4) {
      RawFunFlags = Record[3];
      NumRefs = Record[4];
      RefListStartIndex = 5;
      if (Version >= 5) {
        NumRORefs = Record[5];
        RefListStartIndex = 6;
        if (Version >= 7) {
          NumWORefs = Record[6];
          RefListStartIndex = 7;
        }
      }
    }

    auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
    // The module path string ref set in the summary must be owned by the
    // index's module string table. Since we don't have a module path
    // string table section in the per-module index, we create a single
    // module path string table entry with an empty (0) ID to take
    // ownership.
    int CallGraphEdgeStartIndex = RefListStartIndex + NumRefs;
    assert(Record.size() >= RefListStartIndex + NumRefs &&(static_cast <bool> (Record.size() >= RefListStartIndex
 + NumRefs && "Record size inconsistent with number of references"
) ? void (0) : __assert_fail ("Record.size() >= RefListStartIndex + NumRefs && \"Record size inconsistent with number of references\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 6314, __extension__
 __PRETTY_FUNCTION__))
           "Record size inconsistent with number of references")(static_cast <bool> (Record.size() >= RefListStartIndex
 + NumRefs && "Record size inconsistent with number of references"
) ? void (0) : __assert_fail ("Record.size() >= RefListStartIndex + NumRefs && \"Record size inconsistent with number of references\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 6314, __extension__
 __PRETTY_FUNCTION__));
    std::vector<ValueInfo> Refs = makeRefList(
        ArrayRef<uint64_t>(Record).slice(RefListStartIndex, NumRefs));
    bool HasProfile = (BitCode == bitc::FS_PERMODULE_PROFILE);
    bool HasRelBF = (BitCode == bitc::FS_PERMODULE_RELBF);
    std::vector<FunctionSummary::EdgeTy> Calls = makeCallList(
        ArrayRef<uint64_t>(Record).slice(CallGraphEdgeStartIndex),
        IsOldProfileFormat, HasProfile, HasRelBF);
    setSpecialRefs(Refs, NumRORefs, NumWORefs);
    auto FS = std::make_unique<FunctionSummary>(
        Flags, InstCount, getDecodedFFlags(RawFunFlags), /*EntryCount=*/0,
        std::move(Refs), std::move(Calls), std::move(PendingTypeTests),
        std::move(PendingTypeTestAssumeVCalls),
        std::move(PendingTypeCheckedLoadVCalls),
        std::move(PendingTypeTestAssumeConstVCalls),
        std::move(PendingTypeCheckedLoadConstVCalls),
        std::move(PendingParamAccesses));
    auto VIAndOriginalGUID = getValueInfoFromValueId(ValueID);
    FS->setModulePath(getThisModule()->first());
    FS->setOriginalName(VIAndOriginalGUID.second);
    TheIndex.addGlobalValueSummary(VIAndOriginalGUID.first, std::move(FS));
    break;
  }
  // FS_ALIAS: [valueid, flags, valueid]
  // Aliases must be emitted (and parsed) after all FS_PERMODULE entries, as
  // they expect all aliasee summaries to be available.
  case bitc::FS_ALIAS: {
    unsigned ValueID = Record[0];
    uint64_t RawFlags = Record[1];
    unsigned AliaseeID = Record[2];
    auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
    auto AS = std::make_unique<AliasSummary>(Flags);
    // The module path string ref set in the summary must be owned by the
    // index's module string table. Since we don't have a module path
    // string table section in the per-module index, we create a single
    // module path string table entry with an empty (0) ID to take
    // ownership.
    AS->setModulePath(getThisModule()->first());

    auto AliaseeVI = getValueInfoFromValueId(AliaseeID).first;
    auto AliaseeInModule = TheIndex.findSummaryInModule(AliaseeVI, ModulePath);
    if (!AliaseeInModule)
      return error("Alias expects aliasee summary to be parsed");
    AS->setAliasee(AliaseeVI, AliaseeInModule);

    auto GUID = getValueInfoFromValueId(ValueID);
    AS->setOriginalName(GUID.second);
    TheIndex.addGlobalValueSummary(GUID.first, std::move(AS));
    break;
  }
  // FS_PERMODULE_GLOBALVAR_INIT_REFS: [valueid, flags, varflags, n x valueid]
  case bitc::FS_PERMODULE_GLOBALVAR_INIT_REFS: {
    unsigned ValueID = Record[0];
    uint64_t RawFlags = Record[1];
    unsigned RefArrayStart = 2;
    GlobalVarSummary::GVarFlags GVF(/* ReadOnly */ false,
                                    /* WriteOnly */ false,
                                    /* Constant */ false,
                                    GlobalObject::VCallVisibilityPublic);
    auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
    if (Version >= 5) {
      GVF = getDecodedGVarFlags(Record[2]);
      RefArrayStart = 3;
    }
    std::vector<ValueInfo> Refs =
        makeRefList(ArrayRef<uint64_t>(Record).slice(RefArrayStart));
    auto FS =
        std::make_unique<GlobalVarSummary>(Flags, GVF, std::move(Refs));
    FS->setModulePath(getThisModule()->first());
    auto GUID = getValueInfoFromValueId(ValueID);
    FS->setOriginalName(GUID.second);
    TheIndex.addGlobalValueSummary(GUID.first, std::move(FS));
    break;
  }
  // FS_PERMODULE_VTABLE_GLOBALVAR_INIT_REFS: [valueid, flags, varflags,
  //                        numrefs, numrefs x valueid,
  //                        n x (valueid, offset)]
  case bitc::FS_PERMODULE_VTABLE_GLOBALVAR_INIT_REFS: {
    unsigned ValueID = Record[0];
    uint64_t RawFlags = Record[1];
    GlobalVarSummary::GVarFlags GVF = getDecodedGVarFlags(Record[2]);
    unsigned NumRefs = Record[3];
    unsigned RefListStartIndex = 4;
    unsigned VTableListStartIndex = RefListStartIndex + NumRefs;
    auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
    std::vector<ValueInfo> Refs = makeRefList(
        ArrayRef<uint64_t>(Record).slice(RefListStartIndex, NumRefs));
    VTableFuncList VTableFuncs;
    for (unsigned I = VTableListStartIndex, E = Record.size(); I != E; ++I) {
      ValueInfo Callee = getValueInfoFromValueId(Record[I]).first;
      uint64_t Offset = Record[++I];
      VTableFuncs.push_back({Callee, Offset});
    }
    auto VS =
        std::make_unique<GlobalVarSummary>(Flags, GVF, std::move(Refs));
    VS->setModulePath(getThisModule()->first());
    VS->setVTableFuncs(VTableFuncs);
    auto GUID = getValueInfoFromValueId(ValueID);
    VS->setOriginalName(GUID.second);
    TheIndex.addGlobalValueSummary(GUID.first, std::move(VS));
    break;
  }
  // FS_COMBINED: [valueid, modid, flags, instcount, fflags, numrefs,
  //               numrefs x valueid, n x (valueid)]
  // FS_COMBINED_PROFILE: [valueid, modid, flags, instcount, fflags, numrefs,
  //                       numrefs x valueid, n x (valueid, hotness)]
  case bitc::FS_COMBINED:
  case bitc::FS_COMBINED_PROFILE: {
    unsigned ValueID = Record[0];
    uint64_t ModuleId = Record[1];
    uint64_t RawFlags = Record[2];
    unsigned InstCount = Record[3];
    uint64_t RawFunFlags = 0;
    uint64_t EntryCount = 0;
    unsigned NumRefs = Record[4];
    unsigned NumRORefs = 0, NumWORefs = 0;
    int RefListStartIndex = 5;

    if (Version >= 4) {
      RawFunFlags = Record[4];
      RefListStartIndex = 6;
      size_t NumRefsIndex = 5;
      if (Version >= 5) {
        unsigned NumRORefsOffset = 1;
        RefListStartIndex = 7;
        if (Version >= 6) {
          NumRefsIndex = 6;
          EntryCount = Record[5];
          RefListStartIndex = 8;
          if (Version >= 7) {
            RefListStartIndex = 9;
            NumWORefs = Record[8];
            NumRORefsOffset = 2;
          }
        }
        NumRORefs = Record[RefListStartIndex - NumRORefsOffset];
      }
      NumRefs = Record[NumRefsIndex];
    }

    auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
    int CallGraphEdgeStartIndex = RefListStartIndex + NumRefs;
    assert(Record.size() >= RefListStartIndex + NumRefs &&(static_cast <bool> (Record.size() >= RefListStartIndex
 + NumRefs && "Record size inconsistent with number of references"
) ? void (0) : __assert_fail ("Record.size() >= RefListStartIndex + NumRefs && \"Record size inconsistent with number of references\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 6457, __extension__
 __PRETTY_FUNCTION__))
           "Record size inconsistent with number of references")(static_cast <bool> (Record.size() >= RefListStartIndex
 + NumRefs && "Record size inconsistent with number of references"
) ? void (0) : __assert_fail ("Record.size() >= RefListStartIndex + NumRefs && \"Record size inconsistent with number of references\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 6457, __extension__
 __PRETTY_FUNCTION__));
    std::vector<ValueInfo> Refs = makeRefList(
        ArrayRef<uint64_t>(Record).slice(RefListStartIndex, NumRefs));
    bool HasProfile = (BitCode == bitc::FS_COMBINED_PROFILE);
    std::vector<FunctionSummary::EdgeTy> Edges = makeCallList(
        ArrayRef<uint64_t>(Record).slice(CallGraphEdgeStartIndex),
        IsOldProfileFormat, HasProfile, false);
    ValueInfo VI = getValueInfoFromValueId(ValueID).first;
    setSpecialRefs(Refs, NumRORefs, NumWORefs);
    auto FS = std::make_unique<FunctionSummary>(
        Flags, InstCount, getDecodedFFlags(RawFunFlags), EntryCount,
        std::move(Refs), std::move(Edges), std::move(PendingTypeTests),
        std::move(PendingTypeTestAssumeVCalls),
        std::move(PendingTypeCheckedLoadVCalls),
        std::move(PendingTypeTestAssumeConstVCalls),
        std::move(PendingTypeCheckedLoadConstVCalls),
        std::move(PendingParamAccesses));
    LastSeenSummary = FS.get();
    LastSeenGUID = VI.getGUID();
    FS->setModulePath(ModuleIdMap[ModuleId]);
    TheIndex.addGlobalValueSummary(VI, std::move(FS));
    break;
  }
  // FS_COMBINED_ALIAS: [valueid, modid, flags, valueid]
  // Aliases must be emitted (and parsed) after all FS_COMBINED entries, as
  // they expect all aliasee summaries to be available.
  case bitc::FS_COMBINED_ALIAS: {
    unsigned ValueID = Record[0];
    uint64_t ModuleId = Record[1];
    uint64_t RawFlags = Record[2];
    unsigned AliaseeValueId = Record[3];
    auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
    auto AS = std::make_unique<AliasSummary>(Flags);
    LastSeenSummary = AS.get();
    AS->setModulePath(ModuleIdMap[ModuleId]);

    auto AliaseeVI = getValueInfoFromValueId(AliaseeValueId).first;
    auto AliaseeInModule = TheIndex.findSummaryInModule(AliaseeVI, AS->modulePath());
    AS->setAliasee(AliaseeVI, AliaseeInModule);

    ValueInfo VI = getValueInfoFromValueId(ValueID).first;
    LastSeenGUID = VI.getGUID();
    TheIndex.addGlobalValueSummary(VI, std::move(AS));
    break;
  }
  // FS_COMBINED_GLOBALVAR_INIT_REFS: [valueid, modid, flags, n x valueid]
  case bitc::FS_COMBINED_GLOBALVAR_INIT_REFS: {
    unsigned ValueID = Record[0];
    uint64_t ModuleId = Record[1];
    uint64_t RawFlags = Record[2];
    unsigned RefArrayStart = 3;
    GlobalVarSummary::GVarFlags GVF(/* ReadOnly */ false,
                                    /* WriteOnly */ false,
                                    /* Constant */ false,
                                    GlobalObject::VCallVisibilityPublic);
    auto Flags = getDecodedGVSummaryFlags(RawFlags, Version);
    if (Version >= 5) {
      GVF = getDecodedGVarFlags(Record[3]);
      RefArrayStart = 4;
    }
    std::vector<ValueInfo> Refs =
        makeRefList(ArrayRef<uint64_t>(Record).slice(RefArrayStart));
    auto FS =
        std::make_unique<GlobalVarSummary>(Flags, GVF, std::move(Refs));
    LastSeenSummary = FS.get();
    FS->setModulePath(ModuleIdMap[ModuleId]);
    ValueInfo VI = getValueInfoFromValueId(ValueID).first;
    LastSeenGUID = VI.getGUID();
    TheIndex.addGlobalValueSummary(VI, std::move(FS));
    break;
  }
  // FS_COMBINED_ORIGINAL_NAME: [original_name]
  case bitc::FS_COMBINED_ORIGINAL_NAME: {
    uint64_t OriginalName = Record[0];
    if (!LastSeenSummary)
      return error("Name attachment that does not follow a combined record");
    LastSeenSummary->setOriginalName(OriginalName);
    TheIndex.addOriginalName(LastSeenGUID, OriginalName);
    // Reset the LastSeenSummary
    LastSeenSummary = nullptr;
    LastSeenGUID = 0;
    break;
  }
  case bitc::FS_TYPE_TESTS:
    assert(PendingTypeTests.empty())(static_cast <bool> (PendingTypeTests.empty()) ? void (
0) : __assert_fail ("PendingTypeTests.empty()", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 6541, __extension__ __PRETTY_FUNCTION__));
    llvm::append_range(PendingTypeTests, Record);
    break;

  case bitc::FS_TYPE_TEST_ASSUME_VCALLS:
    assert(PendingTypeTestAssumeVCalls.empty())(static_cast <bool> (PendingTypeTestAssumeVCalls.empty(
)) ? void (0) : __assert_fail ("PendingTypeTestAssumeVCalls.empty()"
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 6546, __extension__
 __PRETTY_FUNCTION__));
    for (unsigned I = 0; I != Record.size(); I += 2)
      PendingTypeTestAssumeVCalls.push_back({Record[I], Record[I+1]});
    break;

  case bitc::FS_TYPE_CHECKED_LOAD_VCALLS:
    assert(PendingTypeCheckedLoadVCalls.empty())(static_cast <bool> (PendingTypeCheckedLoadVCalls.empty
()) ? void (0) : __assert_fail ("PendingTypeCheckedLoadVCalls.empty()"
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 6552, __extension__
 __PRETTY_FUNCTION__));
    for (unsigned I = 0; I != Record.size(); I += 2)
      PendingTypeCheckedLoadVCalls.push_back({Record[I], Record[I+1]});
    break;

  case bitc::FS_TYPE_TEST_ASSUME_CONST_VCALL:
    PendingTypeTestAssumeConstVCalls.push_back(
        {{Record[0], Record[1]}, {Record.begin() + 2, Record.end()}});
    break;

  case bitc::FS_TYPE_CHECKED_LOAD_CONST_VCALL:
    PendingTypeCheckedLoadConstVCalls.push_back(
        {{Record[0], Record[1]}, {Record.begin() + 2, Record.end()}});
    break;

  case bitc::FS_CFI_FUNCTION_DEFS: {
    std::set<std::string> &CfiFunctionDefs = TheIndex.cfiFunctionDefs();
    for (unsigned I = 0; I != Record.size(); I += 2)
      CfiFunctionDefs.insert(
          {Strtab.data() + Record[I], static_cast<size_t>(Record[I + 1])});
    break;
  }

  case bitc::FS_CFI_FUNCTION_DECLS: {
    std::set<std::string> &CfiFunctionDecls = TheIndex.cfiFunctionDecls();
    for (unsigned I = 0; I != Record.size(); I += 2)
      CfiFunctionDecls.insert(
          {Strtab.data() + Record[I], static_cast<size_t>(Record[I + 1])});
    break;
  }

  case bitc::FS_TYPE_ID:
    parseTypeIdSummaryRecord(Record, Strtab, TheIndex);
    break;

  case bitc::FS_TYPE_ID_METADATA:
    parseTypeIdCompatibleVtableSummaryRecord(Record);
    break;

  case bitc::FS_BLOCK_COUNT:
    TheIndex.addBlockCount(Record[0]);
    break;

  case bitc::FS_PARAM_ACCESS: {
    PendingParamAccesses = parseParamAccesses(Record);
    break;
  }
  }
}
llvm_unreachable("Exit infinite loop")::llvm::llvm_unreachable_internal("Exit infinite loop", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 6601);
6602}

6604// Parse the  module string table block into the Index.
6605// This populates the ModulePathStringTable map in the index.
6606Error ModuleSummaryIndexBitcodeReader::parseModuleStringTable() {
if (Error Err = Stream.EnterSubBlock(bitc::MODULE_STRTAB_BLOCK_ID))
  return Err;

SmallVector<uint64_t, 64> Record;

SmallString<128> ModulePath;
ModuleSummaryIndex::ModuleInfo *LastSeenModule = nullptr;

while (true) {
  Expected<BitstreamEntry> MaybeEntry = Stream.advanceSkippingSubblocks();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return Error::success();
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  Record.clear();
  Expected<unsigned> MaybeRecord = Stream.readRecord(Entry.ID, Record);
  if (!MaybeRecord)
    return MaybeRecord.takeError();
  switch (MaybeRecord.get()) {
  default: // Default behavior: ignore.
    break;
  case bitc::MST_CODE_ENTRY: {
    // MST_ENTRY: [modid, namechar x N]
    uint64_t ModuleId = Record[0];

    if (convertToString(Record, 1, ModulePath))
      return error("Invalid record");

    LastSeenModule = TheIndex.addModule(ModulePath, ModuleId);
    ModuleIdMap[ModuleId] = LastSeenModule->first();

    ModulePath.clear();
    break;
  }
  /// MST_CODE_HASH: [5*i32]
  case bitc::MST_CODE_HASH: {
    if (Record.size() != 5)
      return error("Invalid hash length " + Twine(Record.size()).str());
    if (!LastSeenModule)
      return error("Invalid hash that does not follow a module path");
    int Pos = 0;
    for (auto &Val : Record) {
      assert(!(Val >> 32) && "Unexpected high bits set")(static_cast <bool> (!(Val >> 32) && "Unexpected high bits set"
) ? void (0) : __assert_fail ("!(Val >> 32) && \"Unexpected high bits set\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 6660, __extension__
 __PRETTY_FUNCTION__));
      LastSeenModule->second.second[Pos++] = Val;
    }
    // Reset LastSeenModule to avoid overriding the hash unexpectedly.
    LastSeenModule = nullptr;
    break;
  }
  }
}
llvm_unreachable("Exit infinite loop")::llvm::llvm_unreachable_internal("Exit infinite loop", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 6669);
6670}

6672namespace {

6674// FIXME: This class is only here to support the transition to llvm::Error. It
6675// will be removed once this transition is complete. Clients should prefer to
6676// deal with the Error value directly, rather than converting to error_code.
6677class BitcodeErrorCategoryType : public std::error_category {
const char *name() const noexcept override {
  return "llvm.bitcode";
}

std::string message(int IE) const override {
  BitcodeError E = static_cast<BitcodeError>(IE);
  switch (E) {
  case BitcodeError::CorruptedBitcode:
    return "Corrupted bitcode";
  }
  llvm_unreachable("Unknown error type!")::llvm::llvm_unreachable_internal("Unknown error type!", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 6688);
}
6690};

6692} // end anonymous namespace

6694static ManagedStatic<BitcodeErrorCategoryType> ErrorCategory;

6696const std::error_category &llvm::BitcodeErrorCategory() {
return *ErrorCategory;
6698}

6700static Expected<StringRef> readBlobInRecord(BitstreamCursor &Stream,
                                          unsigned Block, unsigned RecordID) {
if (Error Err = Stream.EnterSubBlock(Block))
  return std::move(Err);

StringRef Strtab;
while (true) {
  Expected<llvm::BitstreamEntry> MaybeEntry = Stream.advance();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  llvm::BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::EndBlock:
    return Strtab;

  case BitstreamEntry::Error:
    return error("Malformed block");

  case BitstreamEntry::SubBlock:
    if (Error Err = Stream.SkipBlock())
      return std::move(Err);
    break;

  case BitstreamEntry::Record:
    StringRef Blob;
    SmallVector<uint64_t, 1> Record;
    Expected<unsigned> MaybeRecord =
        Stream.readRecord(Entry.ID, Record, &Blob);
    if (!MaybeRecord)
      return MaybeRecord.takeError();
    if (MaybeRecord.get() == RecordID)
      Strtab = Blob;
    break;
  }
}
6736}

6738//===----------------------------------------------------------------------===//
6739// External interface
6740//===----------------------------------------------------------------------===//

6742Expected<std::vector<BitcodeModule>>
6743llvm::getBitcodeModuleList(MemoryBufferRef Buffer) {
auto FOrErr = getBitcodeFileContents(Buffer);
if (!FOrErr)
  return FOrErr.takeError();
return std::move(FOrErr->Mods);
6748}

6750Expected<BitcodeFileContents>
6751llvm::getBitcodeFileContents(MemoryBufferRef Buffer) {
Expected<BitstreamCursor> StreamOrErr = initStream(Buffer);
if (!StreamOrErr)
  return StreamOrErr.takeError();
BitstreamCursor &Stream = *StreamOrErr;

BitcodeFileContents F;
while (true) {
  uint64_t BCBegin = Stream.getCurrentByteNo();

  // We may be consuming bitcode from a client that leaves garbage at the end
  // of the bitcode stream (e.g. Apple's ar tool). If we are close enough to
  // the end that there cannot possibly be another module, stop looking.
  if (BCBegin + 8 >= Stream.getBitcodeBytes().size())
    return F;

  Expected<llvm::BitstreamEntry> MaybeEntry = Stream.advance();
  if (!MaybeEntry)
    return MaybeEntry.takeError();
  llvm::BitstreamEntry Entry = MaybeEntry.get();

  switch (Entry.Kind) {
  case BitstreamEntry::EndBlock:
  case BitstreamEntry::Error:
    return error("Malformed block");

  case BitstreamEntry::SubBlock: {
    uint64_t IdentificationBit = -1ull;
    if (Entry.ID == bitc::IDENTIFICATION_BLOCK_ID) {
      IdentificationBit = Stream.GetCurrentBitNo() - BCBegin * 8;
      if (Error Err = Stream.SkipBlock())
        return std::move(Err);

      {
        Expected<llvm::BitstreamEntry> MaybeEntry = Stream.advance();
        if (!MaybeEntry)
          return MaybeEntry.takeError();
        Entry = MaybeEntry.get();
      }

      if (Entry.Kind != BitstreamEntry::SubBlock ||
          Entry.ID != bitc::MODULE_BLOCK_ID)
        return error("Malformed block");
    }

    if (Entry.ID == bitc::MODULE_BLOCK_ID) {
      uint64_t ModuleBit = Stream.GetCurrentBitNo() - BCBegin * 8;
      if (Error Err = Stream.SkipBlock())
        return std::move(Err);

      F.Mods.push_back({Stream.getBitcodeBytes().slice(
                            BCBegin, Stream.getCurrentByteNo() - BCBegin),
                        Buffer.getBufferIdentifier(), IdentificationBit,
                        ModuleBit});
      continue;
    }

    if (Entry.ID == bitc::STRTAB_BLOCK_ID) {
      Expected<StringRef> Strtab =
          readBlobInRecord(Stream, bitc::STRTAB_BLOCK_ID, bitc::STRTAB_BLOB);
      if (!Strtab)
        return Strtab.takeError();
      // This string table is used by every preceding bitcode module that does
      // not have its own string table. A bitcode file may have multiple
      // string tables if it was created by binary concatenation, for example
      // with "llvm-cat -b".
      for (BitcodeModule &I : llvm::reverse(F.Mods)) {
        if (!I.Strtab.empty())
          break;
        I.Strtab = *Strtab;
      }
      // Similarly, the string table is used by every preceding symbol table;
      // normally there will be just one unless the bitcode file was created
      // by binary concatenation.
      if (!F.Symtab.empty() && F.StrtabForSymtab.empty())
        F.StrtabForSymtab = *Strtab;
      continue;
    }

    if (Entry.ID == bitc::SYMTAB_BLOCK_ID) {
      Expected<StringRef> SymtabOrErr =
          readBlobInRecord(Stream, bitc::SYMTAB_BLOCK_ID, bitc::SYMTAB_BLOB);
      if (!SymtabOrErr)
        return SymtabOrErr.takeError();

      // We can expect the bitcode file to have multiple symbol tables if it
      // was created by binary concatenation. In that case we silently
      // ignore any subsequent symbol tables, which is fine because this is a
      // low level function. The client is expected to notice that the number
      // of modules in the symbol table does not match the number of modules
      // in the input file and regenerate the symbol table.
      if (F.Symtab.empty())
        F.Symtab = *SymtabOrErr;
      continue;
    }

    if (Error Err = Stream.SkipBlock())
      return std::move(Err);
    continue;
  }
  case BitstreamEntry::Record:
    if (Error E = Stream.skipRecord(Entry.ID).takeError())
      return std::move(E);
    continue;
  }
}
6857}

6859/// Get a lazy one-at-time loading module from bitcode.
6860///
6861/// This isn't always used in a lazy context.  In particular, it's also used by
6862/// \a parseModule().  If this is truly lazy, then we need to eagerly pull
6863/// in forward-referenced functions from block address references.
6864///
6865/// \param[in] MaterializeAll Set to \c true if we should materialize
6866/// everything.
6867Expected<std::unique_ptr<Module>>
6868BitcodeModule::getModuleImpl(LLVMContext &Context, bool MaterializeAll,
                           bool ShouldLazyLoadMetadata, bool IsImporting,
                           DataLayoutCallbackTy DataLayoutCallback) {
BitstreamCursor Stream(Buffer);

std::string ProducerIdentification;
if (IdentificationBit != -1ull) {
  if (Error JumpFailed = Stream.JumpToBit(IdentificationBit))
    return std::move(JumpFailed);
  if (Error E =
          readIdentificationBlock(Stream).moveInto(ProducerIdentification))
    return std::move(E);
}

if (Error JumpFailed = Stream.JumpToBit(ModuleBit))
  return std::move(JumpFailed);
auto *R = new BitcodeReader(std::move(Stream), Strtab, ProducerIdentification,
                            Context);

std::unique_ptr<Module> M =
    std::make_unique<Module>(ModuleIdentifier, Context);
M->setMaterializer(R);

// Delay parsing Metadata if ShouldLazyLoadMetadata is true.
if (Error Err = R->parseBitcodeInto(M.get(), ShouldLazyLoadMetadata,
                                    IsImporting, DataLayoutCallback))
  return std::move(Err);

if (MaterializeAll) {
  // Read in the entire module, and destroy the BitcodeReader.
  if (Error Err = M->materializeAll())
    return std::move(Err);
} else {
  // Resolve forward references from blockaddresses.
  if (Error Err = R->materializeForwardReferencedFunctions())
    return std::move(Err);
}
return std::move(M);
6906}

6908Expected<std::unique_ptr<Module>>
6909BitcodeModule::getLazyModule(LLVMContext &Context, bool ShouldLazyLoadMetadata,
                           bool IsImporting) {
return getModuleImpl(Context, false, ShouldLazyLoadMetadata, IsImporting,
                     [](StringRef) { return None; });
6913}

6915// Parse the specified bitcode buffer and merge the index into CombinedIndex.
6916// We don't use ModuleIdentifier here because the client may need to control the
6917// module path used in the combined summary (e.g. when reading summaries for
6918// regular LTO modules).
6919Error BitcodeModule::readSummary(ModuleSummaryIndex &CombinedIndex,
                               StringRef ModulePath, uint64_t ModuleId) {
BitstreamCursor Stream(Buffer);
if (Error JumpFailed = Stream.JumpToBit(ModuleBit))
  return JumpFailed;

ModuleSummaryIndexBitcodeReader R(std::move(Stream), Strtab, CombinedIndex,
                                  ModulePath, ModuleId);
return R.parseModule();
6928}

6930// Parse the specified bitcode buffer, returning the function info index.
6931Expected<std::unique_ptr<ModuleSummaryIndex>> BitcodeModule::getSummary() {
BitstreamCursor Stream(Buffer);
if (Error JumpFailed = Stream.JumpToBit(ModuleBit))
  return std::move(JumpFailed);

auto Index = std::make_unique<ModuleSummaryIndex>(/*HaveGVs=*/false);
ModuleSummaryIndexBitcodeReader R(std::move(Stream), Strtab, *Index,
                                  ModuleIdentifier, 0);

if (Error Err = R.parseModule())
  return std::move(Err);

return std::move(Index);
6944}

6946static Expected<bool> getEnableSplitLTOUnitFlag(BitstreamCursor &Stream,
                                              unsigned ID) {
if (Error Err = Stream.EnterSubBlock(ID))
  return std::move(Err);
SmallVector<uint64_t, 64> Record;

while (true) {
  BitstreamEntry Entry;
  if (Error E = Stream.advanceSkippingSubblocks().moveInto(Entry))
    return std::move(E);

  switch (Entry.Kind) {
  case BitstreamEntry::SubBlock: // Handled for us already.
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    // If no flags record found, conservatively return true to mimic
    // behavior before this flag was added.
    return true;
  case BitstreamEntry::Record:
    // The interesting case.
    break;
  }

  // Look for the FS_FLAGS record.
  Record.clear();
  Expected<unsigned> MaybeBitCode = Stream.readRecord(Entry.ID, Record);
  if (!MaybeBitCode)
    return MaybeBitCode.takeError();
  switch (MaybeBitCode.get()) {
  default: // Default behavior: ignore.
    break;
  case bitc::FS_FLAGS: { // [flags]
    uint64_t Flags = Record[0];
    // Scan flags.
    assert(Flags <= 0x7f && "Unexpected bits in flag")(static_cast <bool> (Flags <= 0x7f && "Unexpected bits in flag"
) ? void (0) : __assert_fail ("Flags <= 0x7f && \"Unexpected bits in flag\""
, "llvm/lib/Bitcode/Reader/BitcodeReader.cpp", 6981, __extension__
 __PRETTY_FUNCTION__));

    return Flags & 0x8;
  }
  }
}
llvm_unreachable("Exit infinite loop")::llvm::llvm_unreachable_internal("Exit infinite loop", "llvm/lib/Bitcode/Reader/BitcodeReader.cpp"
, 6987);
6988}

6990// Check if the given bitcode buffer contains a global value summary block.
6991Expected<BitcodeLTOInfo> BitcodeModule::getLTOInfo() {
BitstreamCursor Stream(Buffer);
if (Error JumpFailed = Stream.JumpToBit(ModuleBit))
  return std::move(JumpFailed);

if (Error Err = Stream.EnterSubBlock(bitc::MODULE_BLOCK_ID))
  return std::move(Err);

while (true) {
  llvm::BitstreamEntry Entry;
  if (Error E = Stream.advance().moveInto(Entry))
    return std::move(E);

  switch (Entry.Kind) {
  case BitstreamEntry::Error:
    return error("Malformed block");
  case BitstreamEntry::EndBlock:
    return BitcodeLTOInfo{/*IsThinLTO=*/false, /*HasSummary=*/false,
                          /*EnableSplitLTOUnit=*/false};

  case BitstreamEntry::SubBlock:
    if (Entry.ID == bitc::GLOBALVAL_SUMMARY_BLOCK_ID) {
      Expected<bool> EnableSplitLTOUnit =
          getEnableSplitLTOUnitFlag(Stream, Entry.ID);
      if (!EnableSplitLTOUnit)
        return EnableSplitLTOUnit.takeError();
      return BitcodeLTOInfo{/*IsThinLTO=*/true, /*HasSummary=*/true,
                            *EnableSplitLTOUnit};
    }

    if (Entry.ID == bitc::FULL_LTO_GLOBALVAL_SUMMARY_BLOCK_ID) {
      Expected<bool> EnableSplitLTOUnit =
          getEnableSplitLTOUnitFlag(Stream, Entry.ID);
      if (!EnableSplitLTOUnit)
        return EnableSplitLTOUnit.takeError();
      return BitcodeLTOInfo{/*IsThinLTO=*/false, /*HasSummary=*/true,
                            *EnableSplitLTOUnit};
    }

    // Ignore other sub-blocks.
    if (Error Err = Stream.SkipBlock())
      return std::move(Err);
    continue;

  case BitstreamEntry::Record:
    if (Expected<unsigned> StreamFailed = Stream.skipRecord(Entry.ID))
      continue;
    else
      return StreamFailed.takeError();
  }
}
7042}

7044static Expected<BitcodeModule> getSingleModule(MemoryBufferRef Buffer) {
Expected<std::vector<BitcodeModule>> MsOrErr = getBitcodeModuleList(Buffer);
if (!MsOrErr)
  return MsOrErr.takeError();

if (MsOrErr->size() != 1)
  return error("Expected a single module");

return (*MsOrErr)[0];
7053}

7055Expected<std::unique_ptr<Module>>
7056llvm::getLazyBitcodeModule(MemoryBufferRef Buffer, LLVMContext &Context,
                         bool ShouldLazyLoadMetadata, bool IsImporting) {
Expected<BitcodeModule> BM = getSingleModule(Buffer);
if (!BM)
  return BM.takeError();

return BM->getLazyModule(Context, ShouldLazyLoadMetadata, IsImporting);
7063}

7065Expected<std::unique_ptr<Module>> llvm::getOwningLazyBitcodeModule(
  std::unique_ptr<MemoryBuffer> &&Buffer, LLVMContext &Context,
  bool ShouldLazyLoadMetadata, bool IsImporting) {
auto MOrErr = getLazyBitcodeModule(*Buffer, Context, ShouldLazyLoadMetadata,
                                   IsImporting);
if (MOrErr)
  (*MOrErr)->setOwnedMemoryBuffer(std::move(Buffer));
return MOrErr;
7073}

7075Expected<std::unique_ptr<Module>>
7076BitcodeModule::parseModule(LLVMContext &Context,
                         DataLayoutCallbackTy DataLayoutCallback) {
return getModuleImpl(Context, true, false, false, DataLayoutCallback);
// TODO: Restore the use-lists to the in-memory state when the bitcode was
// written.  We must defer until the Module has been fully materialized.
7081}

7083Expected<std::unique_ptr<Module>>
7084llvm::parseBitcodeFile(MemoryBufferRef Buffer, LLVMContext &Context,
                     DataLayoutCallbackTy DataLayoutCallback) {
Expected<BitcodeModule> BM = getSingleModule(Buffer);
if (!BM)
  return BM.takeError();

return BM->parseModule(Context, DataLayoutCallback);
7091}

7093Expected<std::string> llvm::getBitcodeTargetTriple(MemoryBufferRef Buffer) {
Expected<BitstreamCursor> StreamOrErr = initStream(Buffer);
if (!StreamOrErr)
  return StreamOrErr.takeError();

return readTriple(*StreamOrErr);
7099}

7101Expected<bool> llvm::isBitcodeContainingObjCCategory(MemoryBufferRef Buffer) {
Expected<BitstreamCursor> StreamOrErr = initStream(Buffer);
if (!StreamOrErr)
  return StreamOrErr.takeError();

return hasObjCCategory(*StreamOrErr);
7107}

7109Expected<std::string> llvm::getBitcodeProducerString(MemoryBufferRef Buffer) {
Expected<BitstreamCursor> StreamOrErr = initStream(Buffer);
if (!StreamOrErr)
  return StreamOrErr.takeError();

return readIdentificationCode(*StreamOrErr);
7115}

7117Error llvm::readModuleSummaryIndex(MemoryBufferRef Buffer,
                                 ModuleSummaryIndex &CombinedIndex,
                                 uint64_t ModuleId) {
Expected<BitcodeModule> BM = getSingleModule(Buffer);
if (!BM)
  return BM.takeError();

return BM->readSummary(CombinedIndex, BM->getModuleIdentifier(), ModuleId);
7125}

7127Expected<std::unique_ptr<ModuleSummaryIndex>>
7128llvm::getModuleSummaryIndex(MemoryBufferRef Buffer) {
Expected<BitcodeModule> BM = getSingleModule(Buffer);
if (!BM)
  return BM.takeError();

return BM->getSummary();
7134}

7136Expected<BitcodeLTOInfo> llvm::getBitcodeLTOInfo(MemoryBufferRef Buffer) {
Expected<BitcodeModule> BM = getSingleModule(Buffer);
if (!BM)
  return BM.takeError();

return BM->getLTOInfo();
7142}

7144Expected<std::unique_ptr<ModuleSummaryIndex>>
7145llvm::getModuleSummaryIndexForFile(StringRef Path,
                                 bool IgnoreEmptyThinLTOIndexFile) {
ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
    MemoryBuffer::getFileOrSTDIN(Path);
if (!FileOrErr)
  return errorCodeToError(FileOrErr.getError());
if (IgnoreEmptyThinLTOIndexFile && !(*FileOrErr)->getBufferSize())
  return nullptr;
return getModuleSummaryIndex(**FileOrErr);
7154}

←

/build/llvm-toolchain-snapshot-15~++20220208102626+b9f1e1c36c2e/llvm/include/llvm/Support/Error.h

1//===- llvm/Support/Error.h - Recoverable error handling --------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines an API used to report recoverable errors.
10//
11//===----------------------------------------------------------------------===//
12 
13#ifndef LLVM_SUPPORT_ERROR_H
14#define LLVM_SUPPORT_ERROR_H
15 
16#include "llvm-c/Error.h"
17#include "llvm/ADT/SmallVector.h"
18#include "llvm/ADT/StringExtras.h"
19#include "llvm/ADT/Twine.h"
20#include "llvm/Config/abi-breaking.h"
21#include "llvm/Support/AlignOf.h"
22#include "llvm/Support/Compiler.h"
23#include "llvm/Support/Debug.h"
24#include "llvm/Support/ErrorHandling.h"
25#include "llvm/Support/ErrorOr.h"
26#include "llvm/Support/Format.h"
27#include "llvm/Support/raw_ostream.h"
28#include <cassert>
29#include <cstdint>
30#include <cstdlib>
31#include <functional>
32#include <memory>
33#include <new>
34#include <string>
35#include <system_error>
36#include <type_traits>
37#include <utility>
38#include <vector>
39 
40namespace llvm {
41 
42class ErrorSuccess;
43 
44/// Base class for error info classes. Do not extend this directly: Extend
45/// the ErrorInfo template subclass instead.
46class ErrorInfoBase {
47public:
48  virtual ~ErrorInfoBase() = default;
49 
50  /// Print an error message to an output stream.
51  virtual void log(raw_ostream &OS) const = 0;
52 
53  /// Return the error message as a string.
54  virtual std::string message() const {
55    std::string Msg;
56    raw_string_ostream OS(Msg);
57    log(OS);
58    return OS.str();
59  }
60 
61  /// Convert this error to a std::error_code.
62  ///
63  /// This is a temporary crutch to enable interaction with code still
64  /// using std::error_code. It will be removed in the future.
65  virtual std::error_code convertToErrorCode() const = 0;
66 
67  // Returns the class ID for this type.
68  static const void *classID() { return &ID; }
69 
70  // Returns the class ID for the dynamic type of this ErrorInfoBase instance.
71  virtual const void *dynamicClassID() const = 0;
72 
73  // Check whether this instance is a subclass of the class identified by
74  // ClassID.
75  virtual bool isA(const void *const ClassID) const {
76    return ClassID == classID();
77  }
78 
79  // Check whether this instance is a subclass of ErrorInfoT.
80  template <typename ErrorInfoT> bool isA() const {
81    return isA(ErrorInfoT::classID());
82  }
83 
84private:
85  virtual void anchor();
86 
87  static char ID;
88};
89 
90/// Lightweight error class with error context and mandatory checking.
91///
92/// Instances of this class wrap a ErrorInfoBase pointer. Failure states
93/// are represented by setting the pointer to a ErrorInfoBase subclass
94/// instance containing information describing the failure. Success is
95/// represented by a null pointer value.
96///
97/// Instances of Error also contains a 'Checked' flag, which must be set
98/// before the destructor is called, otherwise the destructor will trigger a
99/// runtime error. This enforces at runtime the requirement that all Error
100/// instances be checked or returned to the caller.
101///
102/// There are two ways to set the checked flag, depending on what state the
103/// Error instance is in. For Error instances indicating success, it
104/// is sufficient to invoke the boolean conversion operator. E.g.:
105///
106///   @code{.cpp}
107///   Error foo(<...>);
108///
109///   if (auto E = foo(<...>))
110///     return E; // <- Return E if it is in the error state.
111///   // We have verified that E was in the success state. It can now be safely
112///   // destroyed.
113///   @endcode
114///
115/// A success value *can not* be dropped. For example, just calling 'foo(<...>)'
116/// without testing the return value will raise a runtime error, even if foo
117/// returns success.
118///
119/// For Error instances representing failure, you must use either the
120/// handleErrors or handleAllErrors function with a typed handler. E.g.:
121///
122///   @code{.cpp}
123///   class MyErrorInfo : public ErrorInfo<MyErrorInfo> {
124///     // Custom error info.
125///   };
126///
127///   Error foo(<...>) { return make_error<MyErrorInfo>(...); }
128///
129///   auto E = foo(<...>); // <- foo returns failure with MyErrorInfo.
130///   auto NewE =
131///     handleErrors(E,
132///       [](const MyErrorInfo &M) {
133///         // Deal with the error.
134///       },
135///       [](std::unique_ptr<OtherError> M) -> Error {
136///         if (canHandle(*M)) {
137///           // handle error.
138///           return Error::success();
139///         }
140///         // Couldn't handle this error instance. Pass it up the stack.
141///         return Error(std::move(M));
142///       );
143///   // Note - we must check or return NewE in case any of the handlers
144///   // returned a new error.
145///   @endcode
146///
147/// The handleAllErrors function is identical to handleErrors, except
148/// that it has a void return type, and requires all errors to be handled and
149/// no new errors be returned. It prevents errors (assuming they can all be
150/// handled) from having to be bubbled all the way to the top-level.
151///
152/// *All* Error instances must be checked before destruction, even if
153/// they're moved-assigned or constructed from Success values that have already
154/// been checked. This enforces checking through all levels of the call stack.
155class LLVM_NODISCARD[[clang::warn_unused_result]] Error {
156  // ErrorList needs to be able to yank ErrorInfoBase pointers out of Errors
157  // to add to the error list. It can't rely on handleErrors for this, since
158  // handleErrors does not support ErrorList handlers.
159  friend class ErrorList;
160 
161  // handleErrors needs to be able to set the Checked flag.
162  template <typename... HandlerTs>
163  friend Error handleErrors(Error E, HandlerTs &&... Handlers);
164 
165  // Expected<T> needs to be able to steal the payload when constructed from an
166  // error.
167  template <typename T> friend class Expected;
168 
169  // wrap needs to be able to steal the payload.
170  friend LLVMErrorRef wrap(Error);
171 
172protected:
173  /// Create a success value. Prefer using 'Error::success()' for readability
174  Error() {
175    setPtr(nullptr);
176    setChecked(false);
177  }
178 
179public:
180  /// Create a success value.
181  static ErrorSuccess success();
182 
183  // Errors are not copy-constructable.
184  Error(const Error &Other) = delete;
185 
186  /// Move-construct an error value. The newly constructed error is considered
187  /// unchecked, even if the source error had been checked. The original error
188  /// becomes a checked Success value, regardless of its original state.
189  Error(Error &&Other) {
190    setChecked(true);
191    *this = std::move(Other);
192  }
193 
194  /// Create an error value. Prefer using the 'make_error' function, but
195  /// this constructor can be useful when "re-throwing" errors from handlers.
196  Error(std::unique_ptr<ErrorInfoBase> Payload) {
197    setPtr(Payload.release());
198    setChecked(false);
199  }
200 
201  // Errors are not copy-assignable.
202  Error &operator=(const Error &Other) = delete;
203 
204  /// Move-assign an error value. The current error must represent success, you
205  /// you cannot overwrite an unhandled error. The current error is then
206  /// considered unchecked. The source error becomes a checked success value,
207  /// regardless of its original state.
208  Error &operator=(Error &&Other) {
209    // Don't allow overwriting of unchecked values.
210    assertIsChecked();
211    setPtr(Other.getPtr());
212 
213    // This Error is unchecked, even if the source error was checked.
214    setChecked(false);
215 
216    // Null out Other's payload and set its checked bit.
217    Other.setPtr(nullptr);
218    Other.setChecked(true);
219 
220    return *this;
221  }
222 
223  /// Destroy a Error. Fails with a call to abort() if the error is
224  /// unchecked.
225  ~Error() {
226    assertIsChecked();
227    delete getPtr();
228  }
229 
230  /// Bool conversion. Returns true if this Error is in a failure state,
231  /// and false if it is in an accept state. If the error is in a Success state
232  /// it will be considered checked.
233  explicit operator bool() {
234    setChecked(getPtr() == nullptr);
235    return getPtr() != nullptr;
236  }
237 
238  /// Check whether one error is a subclass of another.
239  template <typename ErrT> bool isA() const {
240    return getPtr() && getPtr()->isA(ErrT::classID());
241  }
242 
243  /// Returns the dynamic class id of this error, or null if this is a success
244  /// value.
245  const void* dynamicClassID() const {
246    if (!getPtr())
247      return nullptr;
248    return getPtr()->dynamicClassID();
249  }
250 
251private:
252#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
253  // assertIsChecked() happens very frequently, but under normal circumstances
254  // is supposed to be a no-op.  So we want it to be inlined, but having a bunch
255  // of debug prints can cause the function to be too large for inlining.  So
256  // it's important that we define this function out of line so that it can't be
257  // inlined.
258  [[noreturn]] void fatalUncheckedError() const;
259#endif
260 
261  void assertIsChecked() {
262#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
263    if (LLVM_UNLIKELY(!getChecked() || getPtr())__builtin_expect((bool)(!getChecked() || getPtr()), false))
264      fatalUncheckedError();
265#endif
266  }
267 
268  ErrorInfoBase *getPtr() const {
269#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
270    return reinterpret_cast<ErrorInfoBase*>(
271             reinterpret_cast<uintptr_t>(Payload) &
272             ~static_cast<uintptr_t>(0x1));
273#else
274    return Payload;
275#endif
276  }
277 
278  void setPtr(ErrorInfoBase *EI) {
279#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
280    Payload = reinterpret_cast<ErrorInfoBase*>(
281                (reinterpret_cast<uintptr_t>(EI) &
282                 ~static_cast<uintptr_t>(0x1)) |
283                (reinterpret_cast<uintptr_t>(Payload) & 0x1));
284#else
285    Payload = EI;
286#endif
287  }
288 
289  bool getChecked() const {
290#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
291    return (reinterpret_cast<uintptr_t>(Payload) & 0x1) == 0;
292#else
293    return true;
294#endif
295  }
296 
297  void setChecked(bool V) {
298#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
299    Payload = reinterpret_cast<ErrorInfoBase*>(
300                (reinterpret_cast<uintptr_t>(Payload) &
301                  ~static_cast<uintptr_t>(0x1)) |
302                  (V ? 0 : 1));
303#endif
304  }
305 
306  std::unique_ptr<ErrorInfoBase> takePayload() {
307    std::unique_ptr<ErrorInfoBase> Tmp(getPtr());
308    setPtr(nullptr);
309    setChecked(true);
310    return Tmp;
311  }
312 
313  friend raw_ostream &operator<<(raw_ostream &OS, const Error &E) {
314    if (auto *P = E.getPtr())
315      P->log(OS);
316    else
317      OS << "success";
318    return OS;
319  }
320 
321  ErrorInfoBase *Payload = nullptr;
322};
323 
324/// Subclass of Error for the sole purpose of identifying the success path in
325/// the type system. This allows to catch invalid conversion to Expected<T> at
326/// compile time.
327class ErrorSuccess final : public Error {};
328 
329inline ErrorSuccess Error::success() { return ErrorSuccess(); }
330 
331/// Make a Error instance representing failure using the given error info
332/// type.
333template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&... Args) {
334  return Error(std::make_unique<ErrT>(std::forward<ArgTs>(Args)...));
335}
336 
337/// Base class for user error types. Users should declare their error types
338/// like:
339///
340/// class MyError : public ErrorInfo<MyError> {
341///   ....
342/// };
343///
344/// This class provides an implementation of the ErrorInfoBase::kind
345/// method, which is used by the Error RTTI system.
346template <typename ThisErrT, typename ParentErrT = ErrorInfoBase>
347class ErrorInfo : public ParentErrT {
348public:
349  using ParentErrT::ParentErrT; // inherit constructors
350 
351  static const void *classID() { return &ThisErrT::ID; }
352 
353  const void *dynamicClassID() const override { return &ThisErrT::ID; }
354 
355  bool isA(const void *const ClassID) const override {
356    return ClassID == classID() || ParentErrT::isA(ClassID);
357  }
358};
359 
360/// Special ErrorInfo subclass representing a list of ErrorInfos.
361/// Instances of this class are constructed by joinError.
362class ErrorList final : public ErrorInfo<ErrorList> {
363  // handleErrors needs to be able to iterate the payload list of an
364  // ErrorList.
365  template <typename... HandlerTs>
366  friend Error handleErrors(Error E, HandlerTs &&... Handlers);
367 
368  // joinErrors is implemented in terms of join.
369  friend Error joinErrors(Error, Error);
370 
371public:
372  void log(raw_ostream &OS) const override {
373    OS << "Multiple errors:\n";
374    for (const auto &ErrPayload : Payloads) {
375      ErrPayload->log(OS);
376      OS << "\n";
377    }
378  }
379 
380  std::error_code convertToErrorCode() const override;
381 
382  // Used by ErrorInfo::classID.
383  static char ID;
384 
385private:
386  ErrorList(std::unique_ptr<ErrorInfoBase> Payload1,
387            std::unique_ptr<ErrorInfoBase> Payload2) {
388    assert(!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() &&(static_cast <bool> (!Payload1->isA<ErrorList>
() && !Payload2->isA<ErrorList>() &&
 "ErrorList constructor payloads should be singleton errors")
 ? void (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "llvm/include/llvm/Support/Error.h", 389, __extension__ __PRETTY_FUNCTION__
))
389           "ErrorList constructor payloads should be singleton errors")(static_cast <bool> (!Payload1->isA<ErrorList>
() && !Payload2->isA<ErrorList>() &&
 "ErrorList constructor payloads should be singleton errors")
 ? void (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "llvm/include/llvm/Support/Error.h", 389, __extension__ __PRETTY_FUNCTION__
));
390    Payloads.push_back(std::move(Payload1));
391    Payloads.push_back(std::move(Payload2));
392  }
393 
394  static Error join(Error E1, Error E2) {
395    if (!E1)
396      return E2;
397    if (!E2)
398      return E1;
399    if (E1.isA<ErrorList>()) {
400      auto &E1List = static_cast<ErrorList &>(*E1.getPtr());
401      if (E2.isA<ErrorList>()) {
402        auto E2Payload = E2.takePayload();
403        auto &E2List = static_cast<ErrorList &>(*E2Payload);
404        for (auto &Payload : E2List.Payloads)
405          E1List.Payloads.push_back(std::move(Payload));
406      } else
407        E1List.Payloads.push_back(E2.takePayload());
408 
409      return E1;
410    }
411    if (E2.isA<ErrorList>()) {
412      auto &E2List = static_cast<ErrorList &>(*E2.getPtr());
413      E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload());
414      return E2;
415    }
416    return Error(std::unique_ptr<ErrorList>(
417        new ErrorList(E1.takePayload(), E2.takePayload())));
418  }
419 
420  std::vector<std::unique_ptr<ErrorInfoBase>> Payloads;
421};
422 
423/// Concatenate errors. The resulting Error is unchecked, and contains the
424/// ErrorInfo(s), if any, contained in E1, followed by the
425/// ErrorInfo(s), if any, contained in E2.
426inline Error joinErrors(Error E1, Error E2) {
427  return ErrorList::join(std::move(E1), std::move(E2));
428}
429 
430/// Tagged union holding either a T or a Error.
431///
432/// This class parallels ErrorOr, but replaces error_code with Error. Since
433/// Error cannot be copied, this class replaces getError() with
434/// takeError(). It also adds an bool errorIsA<ErrT>() method for testing the
435/// error class type.
436///
437/// Example usage of 'Expected<T>' as a function return type:
438///
439///   @code{.cpp}
440///     Expected<int> myDivide(int A, int B) {
441///       if (B == 0) {
442///         // return an Error
443///         return createStringError(inconvertibleErrorCode(),
444///                                  "B must not be zero!");
445///       }
446///       // return an integer
447///       return A / B;
448///     }
449///   @endcode
450///
451///   Checking the results of to a function returning 'Expected<T>':
452///   @code{.cpp}
453///     if (auto E = Result.takeError()) {
454///       // We must consume the error. Typically one of:
455///       // - return the error to our caller
456///       // - toString(), when logging
457///       // - consumeError(), to silently swallow the error
458///       // - handleErrors(), to distinguish error types
459///       errs() << "Problem with division " << toString(std::move(E)) << "\n";
460///       return;
461///     }
462///     // use the result
463///     outs() << "The answer is " << *Result << "\n";
464///   @endcode
465///
466///  For unit-testing a function returning an 'Expceted<T>', see the
467///  'EXPECT_THAT_EXPECTED' macros in llvm/Testing/Support/Error.h
468 
469template <class T> class LLVM_NODISCARD[[clang::warn_unused_result]] Expected {
470  template <class T1> friend class ExpectedAsOutParameter;
471  template <class OtherT> friend class Expected;
472 
473  static constexpr bool isRef = std::is_reference<T>::value;
474 
475  using wrap = std::reference_wrapper<std::remove_reference_t<T>>;
476 
477  using error_type = std::unique_ptr<ErrorInfoBase>;
478 
479public:
480  using storage_type = std::conditional_t<isRef, wrap, T>;
481  using value_type = T;
482 
483private:
484  using reference = std::remove_reference_t<T> &;
485  using const_reference = const std::remove_reference_t<T> &;
486  using pointer = std::remove_reference_t<T> *;
487  using const_pointer = const std::remove_reference_t<T> *;
488 
489public:
490  /// Create an Expected<T> error value from the given Error.
491  Expected(Error Err)
492      : HasError(true)
493#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
494        // Expected is unchecked upon construction in Debug builds.
495        , Unchecked(true)
496#endif
497  {
498    assert(Err && "Cannot create Expected<T> from Error success value.")(static_cast <bool> (Err && "Cannot create Expected<T> from Error success value."
) ? void (0) : __assert_fail ("Err && \"Cannot create Expected<T> from Error success value.\""
, "llvm/include/llvm/Support/Error.h", 498, __extension__ __PRETTY_FUNCTION__
));
499    new (getErrorStorage()) error_type(Err.takePayload());
500  }
501 
502  /// Forbid to convert from Error::success() implicitly, this avoids having
503  /// Expected<T> foo() { return Error::success(); } which compiles otherwise
504  /// but triggers the assertion above.
505  Expected(ErrorSuccess) = delete;
506 
507  /// Create an Expected<T> success value from the given OtherT value, which
508  /// must be convertible to T.
509  template <typename OtherT>
510  Expected(OtherT &&Val,
511           std::enable_if_t<std::is_convertible<OtherT, T>::value> * = nullptr)
512      : HasError(false)
513#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
514        // Expected is unchecked upon construction in Debug builds.
515        ,
516        Unchecked(true)
517#endif
518  {
519    new (getStorage()) storage_type(std::forward<OtherT>(Val));
520  }
521 
522  /// Move construct an Expected<T> value.
523  Expected(Expected &&Other) { moveConstruct(std::move(Other)); }
524 
525  /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
526  /// must be convertible to T.
527  template <class OtherT>
528  Expected(
529      Expected<OtherT> &&Other,
530      std::enable_if_t<std::is_convertible<OtherT, T>::value> * = nullptr) {
531    moveConstruct(std::move(Other));
532  }
533 
534  /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
535  /// isn't convertible to T.
536  template <class OtherT>
537  explicit Expected(
538      Expected<OtherT> &&Other,
539      std::enable_if_t<!std::is_convertible<OtherT, T>::value> * = nullptr) {
540    moveConstruct(std::move(Other));
541  }
542 
543  /// Move-assign from another Expected<T>.
544  Expected &operator=(Expected &&Other) {
545    moveAssign(std::move(Other));
546    return *this;
547  }
548 
549  /// Destroy an Expected<T>.
550  ~Expected() {
551    assertIsChecked();
552    if (!HasError)
553      getStorage()->~storage_type();
554    else
555      getErrorStorage()->~error_type();
556  }
557 
558  /// Return false if there is an error.
559  explicit operator bool() {
560#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
561    Unchecked = HasError;
562#endif
563    return !HasError;
5
←
Assuming field 'HasError' is false, which participates in a condition later→
6
←
Returning the value 1, which participates in a condition later→
12
←
Assuming field 'HasError' is false, which participates in a condition later→
13
←
Returning the value 1, which participates in a condition later→
564  }
565 
566  /// Returns a reference to the stored T value.
567  reference get() {
568    assertIsChecked();
569    return *getStorage();
570  }
571 
572  /// Returns a const reference to the stored T value.
573  const_reference get() const {
574    assertIsChecked();
575    return const_cast<Expected<T> *>(this)->get();
576  }
577 
578  /// Returns \a takeError() after moving the held T (if any) into \p V.
579  template <class OtherT>
580  Error moveInto(OtherT &Value,
581                 std::enable_if_t<std::is_assignable<OtherT &, T &&>::value> * =
582                     nullptr) && {
583    if (*this)
584      Value = std::move(get());
585    return takeError();
586  }
587 
588  /// Check that this Expected<T> is an error of type ErrT.
589  template <typename ErrT> bool errorIsA() const {
590    return HasError && (*getErrorStorage())->template isA<ErrT>();
591  }
592 
593  /// Take ownership of the stored error.
594  /// After calling this the Expected<T> is in an indeterminate state that can
595  /// only be safely destructed. No further calls (beside the destructor) should
596  /// be made on the Expected<T> value.
597  Error takeError() {
598#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
599    Unchecked = false;
600#endif
601    return HasError ? Error(std::move(*getErrorStorage())) : Error::success();
602  }
603 
604  /// Returns a pointer to the stored T value.
605  pointer operator->() {
606    assertIsChecked();
607    return toPointer(getStorage());
608  }
609 
610  /// Returns a const pointer to the stored T value.
611  const_pointer operator->() const {
612    assertIsChecked();
613    return toPointer(getStorage());
614  }
615 
616  /// Returns a reference to the stored T value.
617  reference operator*() {
618    assertIsChecked();
619    return *getStorage();
620  }
621 
622  /// Returns a const reference to the stored T value.
623  const_reference operator*() const {
624    assertIsChecked();
625    return *getStorage();
626  }
627 
628private:
629  template <class T1>
630  static bool compareThisIfSameType(const T1 &a, const T1 &b) {
631    return &a == &b;
632  }
633 
634  template <class T1, class T2>
635  static bool compareThisIfSameType(const T1 &, const T2 &) {
636    return false;
637  }
638 
639  template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) {
640    HasError = Other.HasError;
641#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
642    Unchecked = true;
643    Other.Unchecked = false;
644#endif
645 
646    if (!HasError)
647      new (getStorage()) storage_type(std::move(*Other.getStorage()));
648    else
649      new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage()));
650  }
651 
652  template <class OtherT> void moveAssign(Expected<OtherT> &&Other) {
653    assertIsChecked();
654 
655    if (compareThisIfSameType(*this, Other))
656      return;
657 
658    this->~Expected();
659    new (this) Expected(std::move(Other));
660  }
661 
662  pointer toPointer(pointer Val) { return Val; }
663 
664  const_pointer toPointer(const_pointer Val) const { return Val; }
665 
666  pointer toPointer(wrap *Val) { return &Val->get(); }
667 
668  const_pointer toPointer(const wrap *Val) const { return &Val->get(); }
669 
670  storage_type *getStorage() {
671    assert(!HasError && "Cannot get value when an error exists!")(static_cast <bool> (!HasError && "Cannot get value when an error exists!"
) ? void (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "llvm/include/llvm/Support/Error.h", 671, __extension__ __PRETTY_FUNCTION__
));
672    return reinterpret_cast<storage_type *>(&TStorage);
673  }
674 
675  const storage_type *getStorage() const {
676    assert(!HasError && "Cannot get value when an error exists!")(static_cast <bool> (!HasError && "Cannot get value when an error exists!"
) ? void (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "llvm/include/llvm/Support/Error.h", 676, __extension__ __PRETTY_FUNCTION__
));
677    return reinterpret_cast<const storage_type *>(&TStorage);
678  }
679 
680  error_type *getErrorStorage() {
681    assert(HasError && "Cannot get error when a value exists!")(static_cast <bool> (HasError && "Cannot get error when a value exists!"
) ? void (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "llvm/include/llvm/Support/Error.h", 681, __extension__ __PRETTY_FUNCTION__
));
682    return reinterpret_cast<error_type *>(&ErrorStorage);
683  }
684 
685  const error_type *getErrorStorage() const {
686    assert(HasError && "Cannot get error when a value exists!")(static_cast <bool> (HasError && "Cannot get error when a value exists!"
) ? void (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "llvm/include/llvm/Support/Error.h", 686, __extension__ __PRETTY_FUNCTION__
));
687    return reinterpret_cast<const error_type *>(&ErrorStorage);
688  }
689 
690  // Used by ExpectedAsOutParameter to reset the checked flag.
691  void setUnchecked() {
692#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
693    Unchecked = true;
694#endif
695  }
696 
697#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
698  [[noreturn]] LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline)) void fatalUncheckedExpected() const {
699    dbgs() << "Expected<T> must be checked before access or destruction.\n";
700    if (HasError) {
701      dbgs() << "Unchecked Expected<T> contained error:\n";
702      (*getErrorStorage())->log(dbgs());
703    } else
704      dbgs() << "Expected<T> value was in success state. (Note: Expected<T> "
705                "values in success mode must still be checked prior to being "
706                "destroyed).\n";
707    abort();
708  }
709#endif
710 
711  void assertIsChecked() const {
712#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
713    if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false))
714      fatalUncheckedExpected();
715#endif
716  }
717 
718  union {
719    AlignedCharArrayUnion<storage_type> TStorage;
720    AlignedCharArrayUnion<error_type> ErrorStorage;
721  };
722  bool HasError : 1;
723#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
724  bool Unchecked : 1;
725#endif
726};
727 
728/// Report a serious error, calling any installed error handler. See
729/// ErrorHandling.h.
730[[noreturn]] void report_fatal_error(Error Err, bool gen_crash_diag = true);
731 
732/// Report a fatal error if Err is a failure value.
733///
734/// This function can be used to wrap calls to fallible functions ONLY when it
735/// is known that the Error will always be a success value. E.g.
736///
737///   @code{.cpp}
738///   // foo only attempts the fallible operation if DoFallibleOperation is
739///   // true. If DoFallibleOperation is false then foo always returns
740///   // Error::success().
741///   Error foo(bool DoFallibleOperation);
742///
743///   cantFail(foo(false));
744///   @endcode
745inline void cantFail(Error Err, const char *Msg = nullptr) {
746  if (Err) {
747    if (!Msg)
748      Msg = "Failure value returned from cantFail wrapped call";
749#ifndef NDEBUG
750    std::string Str;
751    raw_string_ostream OS(Str);
752    OS << Msg << "\n" << Err;
753    Msg = OS.str().c_str();
754#endif
755    llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "llvm/include/llvm/Support/Error.h"
, 755);
756  }
757}
758 
759/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
760/// returns the contained value.
761///
762/// This function can be used to wrap calls to fallible functions ONLY when it
763/// is known that the Error will always be a success value. E.g.
764///
765///   @code{.cpp}
766///   // foo only attempts the fallible operation if DoFallibleOperation is
767///   // true. If DoFallibleOperation is false then foo always returns an int.
768///   Expected<int> foo(bool DoFallibleOperation);
769///
770///   int X = cantFail(foo(false));
771///   @endcode
772template <typename T>
773T cantFail(Expected<T> ValOrErr, const char *Msg = nullptr) {
774  if (ValOrErr)
775    return std::move(*ValOrErr);
776  else {
777    if (!Msg)
778      Msg = "Failure value returned from cantFail wrapped call";
779#ifndef NDEBUG
780    std::string Str;
781    raw_string_ostream OS(Str);
782    auto E = ValOrErr.takeError();
783    OS << Msg << "\n" << E;
784    Msg = OS.str().c_str();
785#endif
786    llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "llvm/include/llvm/Support/Error.h"
, 786);
787  }
788}
789 
790/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
791/// returns the contained reference.
792///
793/// This function can be used to wrap calls to fallible functions ONLY when it
794/// is known that the Error will always be a success value. E.g.
795///
796///   @code{.cpp}
797///   // foo only attempts the fallible operation if DoFallibleOperation is
798///   // true. If DoFallibleOperation is false then foo always returns a Bar&.
799///   Expected<Bar&> foo(bool DoFallibleOperation);
800///
801///   Bar &X = cantFail(foo(false));
802///   @endcode
803template <typename T>
804T& cantFail(Expected<T&> ValOrErr, const char *Msg = nullptr) {
805  if (ValOrErr)
806    return *ValOrErr;
807  else {
808    if (!Msg)
809      Msg = "Failure value returned from cantFail wrapped call";
810#ifndef NDEBUG
811    std::string Str;
812    raw_string_ostream OS(Str);
813    auto E = ValOrErr.takeError();
814    OS << Msg << "\n" << E;
815    Msg = OS.str().c_str();
816#endif
817    llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "llvm/include/llvm/Support/Error.h"
, 817);
818  }
819}
820 
821/// Helper for testing applicability of, and applying, handlers for
822/// ErrorInfo types.
823template <typename HandlerT>
824class ErrorHandlerTraits
825    : public ErrorHandlerTraits<decltype(
826          &std::remove_reference<HandlerT>::type::operator())> {};
827 
828// Specialization functions of the form 'Error (const ErrT&)'.
829template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> {
830public:
831  static bool appliesTo(const ErrorInfoBase &E) {
832    return E.template isA<ErrT>();
833  }
834 
835  template <typename HandlerT>
836  static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
837    assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "llvm/include/llvm/Support/Error.h", 837, __extension__ __PRETTY_FUNCTION__
));
838    return H(static_cast<ErrT &>(*E));
839  }
840};
841 
842// Specialization functions of the form 'void (const ErrT&)'.
843template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> {
844public:
845  static bool appliesTo(const ErrorInfoBase &E) {
846    return E.template isA<ErrT>();
847  }
848 
849  template <typename HandlerT>
850  static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
851    assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "llvm/include/llvm/Support/Error.h", 851, __extension__ __PRETTY_FUNCTION__
));
852    H(static_cast<ErrT &>(*E));
853    return Error::success();
854  }
855};
856 
857/// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'.
858template <typename ErrT>
859class ErrorHandlerTraits<Error (&)(std::unique_ptr<ErrT>)> {
860public:
861  static bool appliesTo(const ErrorInfoBase &E) {
862    return E.template isA<ErrT>();
863  }
864 
865  template <typename HandlerT>
866  static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
867    assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "llvm/include/llvm/Support/Error.h", 867, __extension__ __PRETTY_FUNCTION__
));
868    std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
869    return H(std::move(SubE));
870  }
871};
872 
873/// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'.
874template <typename ErrT>
875class ErrorHandlerTraits<void (&)(std::unique_ptr<ErrT>)> {
876public:
877  static bool appliesTo(const ErrorInfoBase &E) {
878    return E.template isA<ErrT>();
879  }
880 
881  template <typename HandlerT>
882  static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
883    assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "llvm/include/llvm/Support/Error.h", 883, __extension__ __PRETTY_FUNCTION__
));
884    std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
885    H(std::move(SubE));
886    return Error::success();
887  }
888};
889 
890// Specialization for member functions of the form 'RetT (const ErrT&)'.
891template <typename C, typename RetT, typename ErrT>
892class ErrorHandlerTraits<RetT (C::*)(ErrT &)>
893    : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
894 
895// Specialization for member functions of the form 'RetT (const ErrT&) const'.
896template <typename C, typename RetT, typename ErrT>
897class ErrorHandlerTraits<RetT (C::*)(ErrT &) const>
898    : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
899 
900// Specialization for member functions of the form 'RetT (const ErrT&)'.
901template <typename C, typename RetT, typename ErrT>
902class ErrorHandlerTraits<RetT (C::*)(const ErrT &)>
903    : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
904 
905// Specialization for member functions of the form 'RetT (const ErrT&) const'.
906template <typename C, typename RetT, typename ErrT>
907class ErrorHandlerTraits<RetT (C::*)(const ErrT &) const>
908    : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
909 
910/// Specialization for member functions of the form
911/// 'RetT (std::unique_ptr<ErrT>)'.
912template <typename C, typename RetT, typename ErrT>
913class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>)>
914    : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
915 
916/// Specialization for member functions of the form
917/// 'RetT (std::unique_ptr<ErrT>) const'.
918template <typename C, typename RetT, typename ErrT>
919class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const>
920    : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
921 
922inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) {
923  return Error(std::move(Payload));
924}
925 
926template <typename HandlerT, typename... HandlerTs>
927Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload,
928                      HandlerT &&Handler, HandlerTs &&... Handlers) {
929  if (ErrorHandlerTraits<HandlerT>::appliesTo(*Payload))
930    return ErrorHandlerTraits<HandlerT>::apply(std::forward<HandlerT>(Handler),
931                                               std::move(Payload));
932  return handleErrorImpl(std::move(Payload),
933                         std::forward<HandlerTs>(Handlers)...);
934}
935 
936/// Pass the ErrorInfo(s) contained in E to their respective handlers. Any
937/// unhandled errors (or Errors returned by handlers) are re-concatenated and
938/// returned.
939/// Because this function returns an error, its result must also be checked
940/// or returned. If you intend to handle all errors use handleAllErrors
941/// (which returns void, and will abort() on unhandled errors) instead.
942template <typename... HandlerTs>
943Error handleErrors(Error E, HandlerTs &&... Hs) {
944  if (!E)
945    return Error::success();
946 
947  std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
948 
949  if (Payload->isA<ErrorList>()) {
950    ErrorList &List = static_cast<ErrorList &>(*Payload);
951    Error R;
952    for (auto &P : List.Payloads)
953      R = ErrorList::join(
954          std::move(R),
955          handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...));
956    return R;
957  }
958 
959  return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...);
960}
961 
962/// Behaves the same as handleErrors, except that by contract all errors
963/// *must* be handled by the given handlers (i.e. there must be no remaining
964/// errors after running the handlers, or llvm_unreachable is called).
965template <typename... HandlerTs>
966void handleAllErrors(Error E, HandlerTs &&... Handlers) {
967  cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...));
968}
969 
970/// Check that E is a non-error, then drop it.
971/// If E is an error, llvm_unreachable will be called.
972inline void handleAllErrors(Error E) {
973  cantFail(std::move(E));
974}
975 
976/// Handle any errors (if present) in an Expected<T>, then try a recovery path.
977///
978/// If the incoming value is a success value it is returned unmodified. If it
979/// is a failure value then it the contained error is passed to handleErrors.
980/// If handleErrors is able to handle the error then the RecoveryPath functor
981/// is called to supply the final result. If handleErrors is not able to
982/// handle all errors then the unhandled errors are returned.
983///
984/// This utility enables the follow pattern:
985///
986///   @code{.cpp}
987///   enum FooStrategy { Aggressive, Conservative };
988///   Expected<Foo> foo(FooStrategy S);
989///
990///   auto ResultOrErr =
991///     handleExpected(
992///       foo(Aggressive),
993///       []() { return foo(Conservative); },
994///       [](AggressiveStrategyError&) {
995///         // Implicitly conusme this - we'll recover by using a conservative
996///         // strategy.
997///       });
998///
999///   @endcode
1000template <typename T, typename RecoveryFtor, typename... HandlerTs>
1001Expected<T> handleExpected(Expected<T> ValOrErr, RecoveryFtor &&RecoveryPath,
1002                           HandlerTs &&... Handlers) {
1003  if (ValOrErr)
1004    return ValOrErr;
1005 
1006  if (auto Err = handleErrors(ValOrErr.takeError(),
1007                              std::forward<HandlerTs>(Handlers)...))
1008    return std::move(Err);
1009 
1010  return RecoveryPath();
1011}
1012 
1013/// Log all errors (if any) in E to OS. If there are any errors, ErrorBanner
1014/// will be printed before the first one is logged. A newline will be printed
1015/// after each error.
1016///
1017/// This function is compatible with the helpers from Support/WithColor.h. You
1018/// can pass any of them as the OS. Please consider using them instead of
1019/// including 'error: ' in the ErrorBanner.
1020///
1021/// This is useful in the base level of your program to allow clean termination
1022/// (allowing clean deallocation of resources, etc.), while reporting error
1023/// information to the user.
1024void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner = {});
1025 
1026/// Write all error messages (if any) in E to a string. The newline character
1027/// is used to separate error messages.
1028inline std::string toString(Error E) {
1029  SmallVector<std::string, 2> Errors;
1030  handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
1031    Errors.push_back(EI.message());
1032  });
1033  return join(Errors.begin(), Errors.end(), "\n");
1034}
1035 
1036/// Consume a Error without doing anything. This method should be used
1037/// only where an error can be considered a reasonable and expected return
1038/// value.
1039///
1040/// Uses of this method are potentially indicative of design problems: If it's
1041/// legitimate to do nothing while processing an "error", the error-producer
1042/// might be more clearly refactored to return an Optional<T>.
1043inline void consumeError(Error Err) {
1044  handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
1045}
1046 
1047/// Convert an Expected to an Optional without doing anything. This method
1048/// should be used only where an error can be considered a reasonable and
1049/// expected return value.
1050///
1051/// Uses of this method are potentially indicative of problems: perhaps the
1052/// error should be propagated further, or the error-producer should just
1053/// return an Optional in the first place.
1054template <typename T> Optional<T> expectedToOptional(Expected<T> &&E) {
1055  if (E)
1056    return std::move(*E);
1057  consumeError(E.takeError());
1058  return None;
1059}
1060 
1061/// Helper for converting an Error to a bool.
1062///
1063/// This method returns true if Err is in an error state, or false if it is
1064/// in a success state.  Puts Err in a checked state in both cases (unlike
1065/// Error::operator bool(), which only does this for success states).
1066inline bool errorToBool(Error Err) {
1067  bool IsError = static_cast<bool>(Err);
1068  if (IsError)
1069    consumeError(std::move(Err));
1070  return IsError;
1071}
1072 
1073/// Helper for Errors used as out-parameters.
1074///
1075/// This helper is for use with the Error-as-out-parameter idiom, where an error
1076/// is passed to a function or method by reference, rather than being returned.
1077/// In such cases it is helpful to set the checked bit on entry to the function
1078/// so that the error can be written to (unchecked Errors abort on assignment)
1079/// and clear the checked bit on exit so that clients cannot accidentally forget
1080/// to check the result. This helper performs these actions automatically using
1081/// RAII:
1082///
1083///   @code{.cpp}
1084///   Result foo(Error &Err) {
1085///     ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1086///     // <body of foo>
1087///     // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1088///   }
1089///   @endcode
1090///
1091/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1092/// used with optional Errors (Error pointers that are allowed to be null). If
1093/// ErrorAsOutParameter took an Error reference, an instance would have to be
1094/// created inside every condition that verified that Error was non-null. By
1095/// taking an Error pointer we can just create one instance at the top of the
1096/// function.
1097class ErrorAsOutParameter {
1098public:
1099  ErrorAsOutParameter(Error *Err) : Err(Err) {
1100    // Raise the checked bit if Err is success.
1101    if (Err)
1102      (void)!!*Err;
1103  }
1104 
1105  ~ErrorAsOutParameter() {
1106    // Clear the checked bit.
1107    if (Err && !*Err)
1108      *Err = Error::success();
1109  }
1110 
1111private:
1112  Error *Err;
1113};
1114 
1115/// Helper for Expected<T>s used as out-parameters.
1116///
1117/// See ErrorAsOutParameter.
1118template <typename T>
1119class ExpectedAsOutParameter {
1120public:
1121  ExpectedAsOutParameter(Expected<T> *ValOrErr)
1122    : ValOrErr(ValOrErr) {
1123    if (ValOrErr)
1124      (void)!!*ValOrErr;
1125  }
1126 
1127  ~ExpectedAsOutParameter() {
1128    if (ValOrErr)
1129      ValOrErr->setUnchecked();
1130  }
1131 
1132private:
1133  Expected<T> *ValOrErr;
1134};
1135 
1136/// This class wraps a std::error_code in a Error.
1137///
1138/// This is useful if you're writing an interface that returns a Error
1139/// (or Expected) and you want to call code that still returns
1140/// std::error_codes.
1141class ECError : public ErrorInfo<ECError> {
1142  friend Error errorCodeToError(std::error_code);
1143 
1144  virtual void anchor() override;
1145 
1146public:
1147  void setErrorCode(std::error_code EC) { this->EC = EC; }
1148  std::error_code convertToErrorCode() const override { return EC; }
1149  void log(raw_ostream &OS) const override { OS << EC.message(); }
1150 
1151  // Used by ErrorInfo::classID.
1152  static char ID;
1153 
1154protected:
1155  ECError() = default;
1156  ECError(std::error_code EC) : EC(EC) {}
1157 
1158  std::error_code EC;
1159};
1160 
1161/// The value returned by this function can be returned from convertToErrorCode
1162/// for Error values where no sensible translation to std::error_code exists.
1163/// It should only be used in this situation, and should never be used where a
1164/// sensible conversion to std::error_code is available, as attempts to convert
1165/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1166/// error to try to convert such a value).
1167std::error_code inconvertibleErrorCode();
1168 
1169/// Helper for converting an std::error_code to a Error.
1170Error errorCodeToError(std::error_code EC);
1171 
1172/// Helper for converting an ECError to a std::error_code.
1173///
1174/// This method requires that Err be Error() or an ECError, otherwise it
1175/// will trigger a call to abort().
1176std::error_code errorToErrorCode(Error Err);
1177 
1178/// Convert an ErrorOr<T> to an Expected<T>.
1179template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1180  if (auto EC = EO.getError())
1181    return errorCodeToError(EC);
1182  return std::move(*EO);
1183}
1184 
1185/// Convert an Expected<T> to an ErrorOr<T>.
1186template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1187  if (auto Err = E.takeError())
1188    return errorToErrorCode(std::move(Err));
1189  return std::move(*E);
1190}
1191 
1192/// This class wraps a string in an Error.
1193///
1194/// StringError is useful in cases where the client is not expected to be able
1195/// to consume the specific error message programmatically (for example, if the
1196/// error message is to be presented to the user).
1197///
1198/// StringError can also be used when additional information is to be printed
1199/// along with a error_code message. Depending on the constructor called, this
1200/// class can either display:
1201///    1. the error_code message (ECError behavior)
1202///    2. a string
1203///    3. the error_code message and a string
1204///
1205/// These behaviors are useful when subtyping is required; for example, when a
1206/// specific library needs an explicit error type. In the example below,
1207/// PDBError is derived from StringError:
1208///
1209///   @code{.cpp}
1210///   Expected<int> foo() {
1211///      return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1212///                                        "Additional information");
1213///   }
1214///   @endcode
1215///
1216class StringError : public ErrorInfo<StringError> {
1217public:
1218  static char ID;
1219 
1220  // Prints EC + S and converts to EC
1221  StringError(std::error_code EC, const Twine &S = Twine());
1222 
1223  // Prints S and converts to EC
1224  StringError(const Twine &S, std::error_code EC);
1225 
1226  void log(raw_ostream &OS) const override;
1227  std::error_code convertToErrorCode() const override;
1228 
1229  const std::string &getMessage() const { return Msg; }
1230 
1231private:
1232  std::string Msg;
1233  std::error_code EC;
1234  const bool PrintMsgOnly = false;
1235};
1236 
1237/// Create formatted StringError object.
1238template <typename... Ts>
1239inline Error createStringError(std::error_code EC, char const *Fmt,
1240                               const Ts &... Vals) {
1241  std::string Buffer;
1242  raw_string_ostream Stream(Buffer);
1243  Stream << format(Fmt, Vals...);
1244  return make_error<StringError>(Stream.str(), EC);
1245}
1246 
1247Error createStringError(std::error_code EC, char const *Msg);
1248 
1249inline Error createStringError(std::error_code EC, const Twine &S) {
1250  return createStringError(EC, S.str().c_str());
1251}
1252 
1253template <typename... Ts>
1254inline Error createStringError(std::errc EC, char const *Fmt,
1255                               const Ts &... Vals) {
1256  return createStringError(std::make_error_code(EC), Fmt, Vals...);
1257}
1258 
1259/// This class wraps a filename and another Error.
1260///
1261/// In some cases, an error needs to live along a 'source' name, in order to
1262/// show more detailed information to the user.
1263class FileError final : public ErrorInfo<FileError> {
1264 
1265  friend Error createFileError(const Twine &, Error);
1266  friend Error createFileError(const Twine &, size_t, Error);
1267 
1268public:
1269  void log(raw_ostream &OS) const override {
1270    assert(Err && "Trying to log after takeError().")(static_cast <bool> (Err && "Trying to log after takeError()."
) ? void (0) : __assert_fail ("Err && \"Trying to log after takeError().\""
, "llvm/include/llvm/Support/Error.h", 1270, __extension__ __PRETTY_FUNCTION__
));
1271    OS << "'" << FileName << "': ";
1272    if (Line.hasValue())
1273      OS << "line " << Line.getValue() << ": ";
1274    Err->log(OS);
1275  }
1276 
1277  std::string messageWithoutFileInfo() const {
1278    std::string Msg;
1279    raw_string_ostream OS(Msg);
1280    Err->log(OS);
1281    return OS.str();
1282  }
1283 
1284  StringRef getFileName() { return FileName; }
1285 
1286  Error takeError() { return Error(std::move(Err)); }
1287 
1288  std::error_code convertToErrorCode() const override;
1289 
1290  // Used by ErrorInfo::classID.
1291  static char ID;
1292 
1293private:
1294  FileError(const Twine &F, Optional<size_t> LineNum,
1295            std::unique_ptr<ErrorInfoBase> E) {
1296    assert(E && "Cannot create FileError from Error success value.")(static_cast <bool> (E && "Cannot create FileError from Error success value."
) ? void (0) : __assert_fail ("E && \"Cannot create FileError from Error success value.\""
, "llvm/include/llvm/Support/Error.h", 1296, __extension__ __PRETTY_FUNCTION__
));
1297    FileName = F.str();
1298    Err = std::move(E);
1299    Line = std::move(LineNum);
1300  }
1301 
1302  static Error build(const Twine &F, Optional<size_t> Line, Error E) {
1303    std::unique_ptr<ErrorInfoBase> Payload;
1304    handleAllErrors(std::move(E),
1305                    [&](std::unique_ptr<ErrorInfoBase> EIB) -> Error {
1306                      Payload = std::move(EIB);
1307                      return Error::success();
1308                    });
1309    return Error(
1310        std::unique_ptr<FileError>(new FileError(F, Line, std::move(Payload))));
1311  }
1312 
1313  std::string FileName;
1314  Optional<size_t> Line;
1315  std::unique_ptr<ErrorInfoBase> Err;
1316};
1317 
1318/// Concatenate a source file path and/or name with an Error. The resulting
1319/// Error is unchecked.
1320inline Error createFileError(const Twine &F, Error E) {
1321  return FileError::build(F, Optional<size_t>(), std::move(E));
1322}
1323 
1324/// Concatenate a source file path and/or name with line number and an Error.
1325/// The resulting Error is unchecked.
1326inline Error createFileError(const Twine &F, size_t Line, Error E) {
1327  return FileError::build(F, Optional<size_t>(Line), std::move(E));
1328}
1329 
1330/// Concatenate a source file path and/or name with a std::error_code 
1331/// to form an Error object.
1332inline Error createFileError(const Twine &F, std::error_code EC) {
1333  return createFileError(F, errorCodeToError(EC));
1334}
1335 
1336/// Concatenate a source file path and/or name with line number and
1337/// std::error_code to form an Error object.
1338inline Error createFileError(const Twine &F, size_t Line, std::error_code EC) {
1339  return createFileError(F, Line, errorCodeToError(EC));
1340}
1341 
1342Error createFileError(const Twine &F, ErrorSuccess) = delete;
1343 
1344/// Helper for check-and-exit error handling.
1345///
1346/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1347///
1348class ExitOnError {
1349public:
1350  /// Create an error on exit helper.
1351  ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1352      : Banner(std::move(Banner)),
1353        GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1354 
1355  /// Set the banner string for any errors caught by operator().
1356  void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1357 
1358  /// Set the exit-code mapper function.
1359  void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1360    this->GetExitCode = std::move(GetExitCode);
1361  }
1362 
1363  /// Check Err. If it's in a failure state log the error(s) and exit.
1364  void operator()(Error Err) const { checkError(std::move(Err)); }
1365 
1366  /// Check E. If it's in a success state then return the contained value. If
1367  /// it's in a failure state log the error(s) and exit.
1368  template <typename T> T operator()(Expected<T> &&E) const {
1369    checkError(E.takeError());
1370    return std::move(*E);
1371  }
1372 
1373  /// Check E. If it's in a success state then return the contained reference. If
1374  /// it's in a failure state log the error(s) and exit.
1375  template <typename T> T& operator()(Expected<T&> &&E) const {
1376    checkError(E.takeError());
1377    return *E;
1378  }
1379 
1380private:
1381  void checkError(Error Err) const {
1382    if (Err) {
1383      int ExitCode = GetExitCode(Err);
1384      logAllUnhandledErrors(std::move(Err), errs(), Banner);
1385      exit(ExitCode);
1386    }
1387  }
1388 
1389  std::string Banner;
1390  std::function<int(const Error &)> GetExitCode;
1391};
1392 
1393/// Conversion from Error to LLVMErrorRef for C error bindings.
1394inline LLVMErrorRef wrap(Error Err) {
1395  return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1396}
1397 
1398/// Conversion from LLVMErrorRef to Error for C error bindings.
1399inline Error unwrap(LLVMErrorRef ErrRef) {
1400  return Error(std::unique_ptr<ErrorInfoBase>(
1401      reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1402}
1403 
1404} // end namespace llvm
1405 
1406#endif // LLVM_SUPPORT_ERROR_H