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llvm/llvm-project/edde212818e3bd1c19ade3cf52927bb7cdfd520f/./llvm/lib/Object/WasmObjectFile.cpp
blob: 713849b4ce63d3db331e8e99ee1d66ac53f2d156 [file]
//===- WasmObjectFile.cpp - Wasm object file implementation ---------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/BinaryFormat/Wasm.h"
#include "llvm/Object/Binary.h"
#include "llvm/Object/Error.h"
#include "llvm/Object/ObjectFile.h"
#include "llvm/Object/SymbolicFile.h"
#include "llvm/Object/Wasm.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/LEB128.h"
#include "llvm/Support/ScopedPrinter.h"
#include "llvm/TargetParser/SubtargetFeature.h"
#include "llvm/TargetParser/Triple.h"
#include <cassert>
#include <cstdint>
#include <cstring>
#define DEBUG_TYPE "wasm-object"
using namespace llvm;
using namespace object;
void WasmSymbol::print(raw_ostream &Out) const {
Out << "Name=" << Info.Name
<< ", Kind=" << toString(wasm::WasmSymbolType(Info.Kind)) << ", Flags=0x"
<< Twine::utohexstr(Info.Flags) << " [";
switch (getBinding()) {
case wasm::WASM_SYMBOL_BINDING_GLOBAL: Out << "global"; break;
case wasm::WASM_SYMBOL_BINDING_LOCAL: Out << "local"; break;
case wasm::WASM_SYMBOL_BINDING_WEAK: Out << "weak"; break;
}
if (isHidden())
Out << ", hidden";
else
Out << ", default";
if (Info.Flags & wasm::WASM_SYMBOL_NO_STRIP)
Out << ", no_strip";
if (Info.Flags & wasm::WASM_SYMBOL_TLS)
Out << ", tls";
if (Info.Flags & wasm::WASM_SYMBOL_ABSOLUTE)
Out << ", absolute";
if (Info.Flags & wasm::WASM_SYMBOL_EXPORTED)
Out << ", exported";
if (isUndefined())
Out << ", undefined";
Out << "]";
if (!isTypeData()) {
Out << ", ElemIndex=" << Info.ElementIndex;
} else if (isDefined()) {
Out << ", Segment=" << Info.DataRef.Segment;
Out << ", Offset=" << Info.DataRef.Offset;
Out << ", Size=" << Info.DataRef.Size;
}
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
LLVM_DUMP_METHOD void WasmSymbol::dump() const { print(dbgs()); }
#endif
Expected<std::unique_ptr<WasmObjectFile>>
ObjectFile::createWasmObjectFile(MemoryBufferRef Buffer) {
Error Err = Error::success();
auto ObjectFile = std::make_unique<WasmObjectFile>(Buffer, Err);
if (Err)
return std::move(Err);
return std::move(ObjectFile);
}
#define VARINT7_MAX ((1 << 7) - 1)
#define VARINT7_MIN (-(1 << 7))
#define VARUINT7_MAX (1 << 7)
#define VARUINT1_MAX (1)
static uint8_t readUint8(WasmObjectFile::ReadContext &Ctx) {
if (Ctx.Ptr == Ctx.End)
report_fatal_error("EOF while reading uint8");
return *Ctx.Ptr++;
}
static uint32_t readUint32(WasmObjectFile::ReadContext &Ctx) {
if (Ctx.Ptr + 4 > Ctx.End)
report_fatal_error("EOF while reading uint32");
uint32_t Result = support::endian::read32le(Ctx.Ptr);
Ctx.Ptr += 4;
return Result;
}
static int32_t readFloat32(WasmObjectFile::ReadContext &Ctx) {
if (Ctx.Ptr + 4 > Ctx.End)
report_fatal_error("EOF while reading float64");
int32_t Result = 0;
memcpy(&Result, Ctx.Ptr, sizeof(Result));
Ctx.Ptr += sizeof(Result);
return Result;
}
static int64_t readFloat64(WasmObjectFile::ReadContext &Ctx) {
if (Ctx.Ptr + 8 > Ctx.End)
report_fatal_error("EOF while reading float64");
int64_t Result = 0;
memcpy(&Result, Ctx.Ptr, sizeof(Result));
Ctx.Ptr += sizeof(Result);
return Result;
}
static uint64_t readULEB128(WasmObjectFile::ReadContext &Ctx) {
unsigned Count;
const char *Error = nullptr;
uint64_t Result = decodeULEB128(Ctx.Ptr, &Count, Ctx.End, &Error);
if (Error)
report_fatal_error(Error);
Ctx.Ptr += Count;
return Result;
}
static StringRef readString(WasmObjectFile::ReadContext &Ctx) {
uint32_t StringLen = readULEB128(Ctx);
if (Ctx.Ptr + StringLen > Ctx.End)
report_fatal_error("EOF while reading string");
StringRef Return =
StringRef(reinterpret_cast<const char *>(Ctx.Ptr), StringLen);
Ctx.Ptr += StringLen;
return Return;
}
static int64_t readLEB128(WasmObjectFile::ReadContext &Ctx) {
unsigned Count;
const char *Error = nullptr;
uint64_t Result = decodeSLEB128(Ctx.Ptr, &Count, Ctx.End, &Error);
if (Error)
report_fatal_error(Error);
Ctx.Ptr += Count;
return Result;
}
static uint8_t readVaruint1(WasmObjectFile::ReadContext &Ctx) {
int64_t Result = readLEB128(Ctx);
if (Result > VARUINT1_MAX || Result < 0)
report_fatal_error("LEB is outside Varuint1 range");
return Result;
}
static int32_t readVarint32(WasmObjectFile::ReadContext &Ctx) {
int64_t Result = readLEB128(Ctx);
if (Result > INT32_MAX || Result < INT32_MIN)
report_fatal_error("LEB is outside Varint32 range");
return Result;
}
static uint32_t readVaruint32(WasmObjectFile::ReadContext &Ctx) {
uint64_t Result = readULEB128(Ctx);
if (Result > UINT32_MAX)
report_fatal_error("LEB is outside Varuint32 range");
return Result;
}
static int64_t readVarint64(WasmObjectFile::ReadContext &Ctx) {
return readLEB128(Ctx);
}
static uint64_t readVaruint64(WasmObjectFile::ReadContext &Ctx) {
return readULEB128(Ctx);
}
static uint8_t readOpcode(WasmObjectFile::ReadContext &Ctx) {
return readUint8(Ctx);
}
static wasm::ValType parseValType(WasmObjectFile::ReadContext &Ctx,
uint32_t Code) {
// only directly encoded FUNCREF/EXTERNREF/EXNREF are supported
// (not ref null func, ref null extern, or ref null exn)
switch (Code) {
case wasm::WASM_TYPE_I32:
case wasm::WASM_TYPE_I64:
case wasm::WASM_TYPE_F32:
case wasm::WASM_TYPE_F64:
case wasm::WASM_TYPE_V128:
case wasm::WASM_TYPE_FUNCREF:
case wasm::WASM_TYPE_EXTERNREF:
case wasm::WASM_TYPE_EXNREF:
return wasm::ValType(Code);
}
if (Code == wasm::WASM_TYPE_NULLABLE || Code == wasm::WASM_TYPE_NONNULLABLE) {
/* Discard HeapType */ readVarint64(Ctx);
}
return wasm::ValType(wasm::ValType::OTHERREF);
}
static Error readInitExpr(wasm::WasmInitExpr &Expr,
WasmObjectFile::ReadContext &Ctx) {
auto Start = Ctx.Ptr;
Expr.Extended = false;
Expr.Inst.Opcode = readOpcode(Ctx);
switch (Expr.Inst.Opcode) {
case wasm::WASM_OPCODE_I32_CONST:
Expr.Inst.Value.Int32 = readVarint32(Ctx);
break;
case wasm::WASM_OPCODE_I64_CONST:
Expr.Inst.Value.Int64 = readVarint64(Ctx);
break;
case wasm::WASM_OPCODE_F32_CONST:
Expr.Inst.Value.Float32 = readFloat32(Ctx);
break;
case wasm::WASM_OPCODE_F64_CONST:
Expr.Inst.Value.Float64 = readFloat64(Ctx);
break;
case wasm::WASM_OPCODE_GLOBAL_GET:
Expr.Inst.Value.Global = readULEB128(Ctx);
break;
case wasm::WASM_OPCODE_REF_NULL: {
/* Discard type */ parseValType(Ctx, readVaruint32(Ctx));
break;
}
default:
Expr.Extended = true;
}
if (!Expr.Extended) {
uint8_t EndOpcode = readOpcode(Ctx);
if (EndOpcode != wasm::WASM_OPCODE_END)
Expr.Extended = true;
}
if (Expr.Extended) {
Ctx.Ptr = Start;
while (true) {
uint8_t Opcode = readOpcode(Ctx);
switch (Opcode) {
case wasm::WASM_OPCODE_I32_CONST:
case wasm::WASM_OPCODE_GLOBAL_GET:
case wasm::WASM_OPCODE_REF_NULL:
case wasm::WASM_OPCODE_REF_FUNC:
case wasm::WASM_OPCODE_I64_CONST:
readULEB128(Ctx);
break;
case wasm::WASM_OPCODE_F32_CONST:
readFloat32(Ctx);
break;
case wasm::WASM_OPCODE_F64_CONST:
readFloat64(Ctx);
break;
case wasm::WASM_OPCODE_I32_ADD:
case wasm::WASM_OPCODE_I32_SUB:
case wasm::WASM_OPCODE_I32_MUL:
case wasm::WASM_OPCODE_I64_ADD:
case wasm::WASM_OPCODE_I64_SUB:
case wasm::WASM_OPCODE_I64_MUL:
break;
case wasm::WASM_OPCODE_GC_PREFIX:
break;
// The GC opcodes are in a separate (prefixed space). This flat switch
// structure works as long as there is no overlap between the GC and
// general opcodes used in init exprs.
case wasm::WASM_OPCODE_STRUCT_NEW:
case wasm::WASM_OPCODE_STRUCT_NEW_DEFAULT:
case wasm::WASM_OPCODE_ARRAY_NEW:
case wasm::WASM_OPCODE_ARRAY_NEW_DEFAULT:
readULEB128(Ctx); // heap type index
break;
case wasm::WASM_OPCODE_ARRAY_NEW_FIXED:
readULEB128(Ctx); // heap type index
readULEB128(Ctx); // array size
break;
case wasm::WASM_OPCODE_REF_I31:
break;
case wasm::WASM_OPCODE_END:
Expr.Body = ArrayRef<uint8_t>(Start, Ctx.Ptr - Start);
return Error::success();
default:
return make_error<GenericBinaryError>("invalid opcode in init_expr: " +
Twine(unsigned(Opcode)),
object_error::parse_failed);
}
}
}
return Error::success();
}
static wasm::WasmLimits readLimits(WasmObjectFile::ReadContext &Ctx) {
wasm::WasmLimits Result;
Result.Flags = readVaruint32(Ctx);
Result.Minimum = readVaruint64(Ctx);
if (Result.Flags & wasm::WASM_LIMITS_FLAG_HAS_MAX)
Result.Maximum = readVaruint64(Ctx);
if (Result.Flags & wasm::WASM_LIMITS_FLAG_HAS_PAGE_SIZE) {
uint32_t PageSizeLog2 = readVaruint32(Ctx);
if (PageSizeLog2 >= 32)
report_fatal_error("log2(wasm page size) too large");
Result.PageSize = 1 << PageSizeLog2;
}
return Result;
}
static wasm::WasmTableType readTableType(WasmObjectFile::ReadContext &Ctx) {
wasm::WasmTableType TableType;
auto ElemType = parseValType(Ctx, readVaruint32(Ctx));
TableType.ElemType = ElemType;
TableType.Limits = readLimits(Ctx);
return TableType;
}
static Error readSection(WasmSection &Section, WasmObjectFile::ReadContext &Ctx,
WasmSectionOrderChecker &Checker) {
Section.Type = readUint8(Ctx);
LLVM_DEBUG(dbgs() << "readSection type=" << Section.Type << "\n");
// When reading the section's size, store the size of the LEB used to encode
// it. This allows objcopy/strip to reproduce the binary identically.
const uint8_t *PreSizePtr = Ctx.Ptr;
uint32_t Size = readVaruint32(Ctx);
Section.HeaderSecSizeEncodingLen = Ctx.Ptr - PreSizePtr;
Section.Offset = Ctx.Ptr - Ctx.Start;
if (Size == 0)
return make_error<StringError>("zero length section",
object_error::parse_failed);
if (Ctx.Ptr + Size > Ctx.End)
return make_error<StringError>("section too large",
object_error::parse_failed);
if (Section.Type == wasm::WASM_SEC_CUSTOM) {
WasmObjectFile::ReadContext SectionCtx;
SectionCtx.Start = Ctx.Ptr;
SectionCtx.Ptr = Ctx.Ptr;
SectionCtx.End = Ctx.Ptr + Size;
Section.Name = readString(SectionCtx);
uint32_t SectionNameSize = SectionCtx.Ptr - SectionCtx.Start;
Ctx.Ptr += SectionNameSize;
Size -= SectionNameSize;
}
if (!Checker.isValidSectionOrder(Section.Type, Section.Name)) {
return make_error<StringError>("out of order section type: " +
llvm::to_string(Section.Type),
object_error::parse_failed);
}
Section.Content = ArrayRef<uint8_t>(Ctx.Ptr, Size);
Ctx.Ptr += Size;
return Error::success();
}
WasmObjectFile::WasmObjectFile(MemoryBufferRef Buffer, Error &Err)
: ObjectFile(Binary::ID_Wasm, Buffer) {
ErrorAsOutParameter ErrAsOutParam(Err);
Header.Magic = getData().substr(0, 4);
if (Header.Magic != StringRef("\0asm", 4)) {
Err = make_error<StringError>("invalid magic number",
object_error::parse_failed);
return;
}
ReadContext Ctx;
Ctx.Start = getData().bytes_begin();
Ctx.Ptr = Ctx.Start + 4;
Ctx.End = Ctx.Start + getData().size();
if (Ctx.Ptr + 4 > Ctx.End) {
Err = make_error<StringError>("missing version number",
object_error::parse_failed);
return;
}
Header.Version = readUint32(Ctx);
if (Header.Version != wasm::WasmVersion) {
Err = make_error<StringError>("invalid version number: " +
Twine(Header.Version),
object_error::parse_failed);
return;
}
WasmSectionOrderChecker Checker;
while (Ctx.Ptr < Ctx.End) {
WasmSection Sec;
if ((Err = readSection(Sec, Ctx, Checker)))
return;
if ((Err = parseSection(Sec)))
return;
Sections.push_back(Sec);
}
}
Error WasmObjectFile::parseSection(WasmSection &Sec) {
ReadContext Ctx;
Ctx.Start = Sec.Content.data();
Ctx.End = Ctx.Start + Sec.Content.size();
Ctx.Ptr = Ctx.Start;
switch (Sec.Type) {
case wasm::WASM_SEC_CUSTOM:
return parseCustomSection(Sec, Ctx);
case wasm::WASM_SEC_TYPE:
return parseTypeSection(Ctx);
case wasm::WASM_SEC_IMPORT:
return parseImportSection(Ctx);
case wasm::WASM_SEC_FUNCTION:
return parseFunctionSection(Ctx);
case wasm::WASM_SEC_TABLE:
return parseTableSection(Ctx);
case wasm::WASM_SEC_MEMORY:
return parseMemorySection(Ctx);
case wasm::WASM_SEC_TAG:
return parseTagSection(Ctx);
case wasm::WASM_SEC_GLOBAL:
return parseGlobalSection(Ctx);
case wasm::WASM_SEC_EXPORT:
return parseExportSection(Ctx);
case wasm::WASM_SEC_START:
return parseStartSection(Ctx);
case wasm::WASM_SEC_ELEM:
return parseElemSection(Ctx);
case wasm::WASM_SEC_CODE:
return parseCodeSection(Ctx);
case wasm::WASM_SEC_DATA:
return parseDataSection(Ctx);
case wasm::WASM_SEC_DATACOUNT:
return parseDataCountSection(Ctx);
default:
return make_error<GenericBinaryError>(
"invalid section type: " + Twine(Sec.Type), object_error::parse_failed);
}
}
Error WasmObjectFile::parseDylinkSection(ReadContext &Ctx) {
// Legacy "dylink" section support.
// See parseDylink0Section for the current "dylink.0" section parsing.
HasDylinkSection = true;
DylinkInfo.MemorySize = readVaruint32(Ctx);
DylinkInfo.MemoryAlignment = readVaruint32(Ctx);
DylinkInfo.TableSize = readVaruint32(Ctx);
DylinkInfo.TableAlignment = readVaruint32(Ctx);
uint32_t Count = readVaruint32(Ctx);
while (Count--) {
DylinkInfo.Needed.push_back(readString(Ctx));
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("dylink section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseDylink0Section(ReadContext &Ctx) {
// See
// https://github.com/WebAssembly/tool-conventions/blob/main/DynamicLinking.md
HasDylinkSection = true;
const uint8_t *OrigEnd = Ctx.End;
while (Ctx.Ptr < OrigEnd) {
Ctx.End = OrigEnd;
uint8_t Type = readUint8(Ctx);
uint32_t Size = readVaruint32(Ctx);
LLVM_DEBUG(dbgs() << "readSubsection type=" << int(Type) << " size=" << Size
<< "\n");
Ctx.End = Ctx.Ptr + Size;
uint32_t Count;
switch (Type) {
case wasm::WASM_DYLINK_MEM_INFO:
DylinkInfo.MemorySize = readVaruint32(Ctx);
DylinkInfo.MemoryAlignment = readVaruint32(Ctx);
DylinkInfo.TableSize = readVaruint32(Ctx);
DylinkInfo.TableAlignment = readVaruint32(Ctx);
break;
case wasm::WASM_DYLINK_NEEDED:
Count = readVaruint32(Ctx);
while (Count--) {
DylinkInfo.Needed.push_back(readString(Ctx));
}
break;
case wasm::WASM_DYLINK_EXPORT_INFO: {
uint32_t Count = readVaruint32(Ctx);
while (Count--) {
DylinkInfo.ExportInfo.push_back({readString(Ctx), readVaruint32(Ctx)});
}
break;
}
case wasm::WASM_DYLINK_IMPORT_INFO: {
uint32_t Count = readVaruint32(Ctx);
while (Count--) {
DylinkInfo.ImportInfo.push_back(
{readString(Ctx), readString(Ctx), readVaruint32(Ctx)});
}
break;
}
case wasm::WASM_DYLINK_RUNTIME_PATH: {
Count = readVaruint32(Ctx);
while (Count--) {
DylinkInfo.RuntimePath.push_back(readString(Ctx));
}
break;
}
case wasm::WASM_DYLINK_TARGET_ARCH:
DylinkInfo.TargetArch = readString(Ctx);
break;
default:
LLVM_DEBUG(dbgs() << "unknown dylink.0 sub-section: " << Type << "\n");
Ctx.Ptr += Size;
break;
}
if (Ctx.Ptr != Ctx.End) {
return make_error<GenericBinaryError>(
"dylink.0 sub-section ended prematurely", object_error::parse_failed);
}
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("dylink.0 section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseNameSection(ReadContext &Ctx) {
llvm::DenseSet<uint64_t> SeenFunctions;
llvm::DenseSet<uint64_t> SeenGlobals;
llvm::DenseSet<uint64_t> SeenSegments;
// If we have linking section (symbol table) or if we are parsing a DSO
// then we don't use the name section for symbol information.
bool PopulateSymbolTable = !HasLinkingSection && !HasDylinkSection;
// If we are using the name section for symbol information then it will
// supersede any symbols created by the export section.
if (PopulateSymbolTable)
Symbols.clear();
while (Ctx.Ptr < Ctx.End) {
uint8_t Type = readUint8(Ctx);
uint32_t Size = readVaruint32(Ctx);
const uint8_t *SubSectionEnd = Ctx.Ptr + Size;
switch (Type) {
case wasm::WASM_NAMES_FUNCTION:
case wasm::WASM_NAMES_GLOBAL:
case wasm::WASM_NAMES_DATA_SEGMENT: {
uint32_t Count = readVaruint32(Ctx);
while (Count--) {
uint32_t Index = readVaruint32(Ctx);
StringRef Name = readString(Ctx);
wasm::NameType nameType = wasm::NameType::FUNCTION;
wasm::WasmSymbolInfo Info{Name,
/*Kind */ wasm::WASM_SYMBOL_TYPE_FUNCTION,
/* Flags */ 0,
/* ImportModule */ std::nullopt,
/* ImportName */ std::nullopt,
/* ExportName */ std::nullopt,
{/* ElementIndex */ Index}};
const wasm::WasmSignature *Signature = nullptr;
const wasm::WasmGlobalType *GlobalType = nullptr;
const wasm::WasmTableType *TableType = nullptr;
if (Type == wasm::WASM_NAMES_FUNCTION) {
if (!SeenFunctions.insert(Index).second)
return make_error<GenericBinaryError>(
"function named more than once", object_error::parse_failed);
if (!isValidFunctionIndex(Index) || Name.empty())
return make_error<GenericBinaryError>("invalid function name entry",
object_error::parse_failed);
if (isDefinedFunctionIndex(Index)) {
wasm::WasmFunction &F = getDefinedFunction(Index);
F.DebugName = Name;
Signature = &Signatures[F.SigIndex];
if (F.ExportName) {
Info.ExportName = F.ExportName;
Info.Flags |= wasm::WASM_SYMBOL_BINDING_GLOBAL;
} else {
Info.Flags |= wasm::WASM_SYMBOL_BINDING_LOCAL;
}
} else {
Info.Flags |= wasm::WASM_SYMBOL_UNDEFINED;
}
} else if (Type == wasm::WASM_NAMES_GLOBAL) {
if (!SeenGlobals.insert(Index).second)
return make_error<GenericBinaryError>("global named more than once",
object_error::parse_failed);
if (!isValidGlobalIndex(Index) || Name.empty())
return make_error<GenericBinaryError>("invalid global name entry",
object_error::parse_failed);
nameType = wasm::NameType::GLOBAL;
Info.Kind = wasm::WASM_SYMBOL_TYPE_GLOBAL;
if (isDefinedGlobalIndex(Index)) {
GlobalType = &getDefinedGlobal(Index).Type;
} else {
Info.Flags |= wasm::WASM_SYMBOL_UNDEFINED;
}
} else {
if (!SeenSegments.insert(Index).second)
return make_error<GenericBinaryError>(
"segment named more than once", object_error::parse_failed);
if (Index >= DataSegments.size())
return make_error<GenericBinaryError>("invalid data segment name entry",
object_error::parse_failed);
nameType = wasm::NameType::DATA_SEGMENT;
Info.Kind = wasm::WASM_SYMBOL_TYPE_DATA;
Info.Flags |= wasm::WASM_SYMBOL_BINDING_LOCAL;
assert(Index < DataSegments.size());
Info.DataRef = wasm::WasmDataReference{
Index, 0, DataSegments[Index].Data.Content.size()};
}
DebugNames.push_back(wasm::WasmDebugName{nameType, Index, Name});
if (PopulateSymbolTable)
Symbols.emplace_back(Info, GlobalType, TableType, Signature);
}
break;
}
// Ignore local names for now
case wasm::WASM_NAMES_LOCAL:
default:
Ctx.Ptr += Size;
break;
}
if (Ctx.Ptr != SubSectionEnd)
return make_error<GenericBinaryError>(
"name sub-section ended prematurely", object_error::parse_failed);
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("name section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseLinkingSection(ReadContext &Ctx) {
HasLinkingSection = true;
LinkingData.Version = readVaruint32(Ctx);
if (LinkingData.Version != wasm::WasmMetadataVersion) {
return make_error<GenericBinaryError>(
"unexpected metadata version: " + Twine(LinkingData.Version) +
" (Expected: " + Twine(wasm::WasmMetadataVersion) + ")",
object_error::parse_failed);
}
const uint8_t *OrigEnd = Ctx.End;
while (Ctx.Ptr < OrigEnd) {
Ctx.End = OrigEnd;
uint8_t Type = readUint8(Ctx);
uint32_t Size = readVaruint32(Ctx);
LLVM_DEBUG(dbgs() << "readSubsection type=" << int(Type) << " size=" << Size
<< "\n");
Ctx.End = Ctx.Ptr + Size;
switch (Type) {
case wasm::WASM_SYMBOL_TABLE:
if (Error Err = parseLinkingSectionSymtab(Ctx))
return Err;
break;
case wasm::WASM_SEGMENT_INFO: {
uint32_t Count = readVaruint32(Ctx);
if (Count > DataSegments.size())
return make_error<GenericBinaryError>("too many segment names",
object_error::parse_failed);
for (uint32_t I = 0; I < Count; I++) {
DataSegments[I].Data.Name = readString(Ctx);
DataSegments[I].Data.Alignment = readVaruint32(Ctx);
if (DataSegments[I].Data.Alignment > 32)
return make_error<GenericBinaryError>(
"invalid data segment alignment: `" + DataSegments[I].Data.Name +
"` (alignment: " + Twine(DataSegments[I].Data.Alignment) +
")",
object_error::parse_failed);
DataSegments[I].Data.LinkingFlags = readVaruint32(Ctx);
}
break;
}
case wasm::WASM_INIT_FUNCS: {
uint32_t Count = readVaruint32(Ctx);
LinkingData.InitFunctions.reserve(Count);
for (uint32_t I = 0; I < Count; I++) {
wasm::WasmInitFunc Init;
Init.Priority = readVaruint32(Ctx);
Init.Symbol = readVaruint32(Ctx);
if (!isValidFunctionSymbol(Init.Symbol))
return make_error<GenericBinaryError>("invalid function symbol: " +
Twine(Init.Symbol),
object_error::parse_failed);
LinkingData.InitFunctions.emplace_back(Init);
}
break;
}
case wasm::WASM_COMDAT_INFO:
if (Error Err = parseLinkingSectionComdat(Ctx))
return Err;
break;
case wasm::WASM_TARGET_ARCH:
LinkingData.TargetArch = readString(Ctx);
break;
default:
Ctx.Ptr += Size;
break;
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>(
"linking sub-section ended prematurely", object_error::parse_failed);
}
if (Ctx.Ptr != OrigEnd)
return make_error<GenericBinaryError>("linking section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseLinkingSectionSymtab(ReadContext &Ctx) {
uint32_t Count = readVaruint32(Ctx);
// Clear out any symbol information that was derived from the exports
// section.
Symbols.clear();
Symbols.reserve(Count);
StringSet<> SymbolNames;
std::vector<wasm::WasmImport *> ImportedGlobals;
std::vector<wasm::WasmImport *> ImportedFunctions;
std::vector<wasm::WasmImport *> ImportedTags;
std::vector<wasm::WasmImport *> ImportedTables;
ImportedGlobals.reserve(Imports.size());
ImportedFunctions.reserve(Imports.size());
ImportedTags.reserve(Imports.size());
ImportedTables.reserve(Imports.size());
for (auto &I : Imports) {
if (I.Kind == wasm::WASM_EXTERNAL_FUNCTION)
ImportedFunctions.emplace_back(&I);
else if (I.Kind == wasm::WASM_EXTERNAL_GLOBAL)
ImportedGlobals.emplace_back(&I);
else if (I.Kind == wasm::WASM_EXTERNAL_TAG)
ImportedTags.emplace_back(&I);
else if (I.Kind == wasm::WASM_EXTERNAL_TABLE)
ImportedTables.emplace_back(&I);
}
while (Count--) {
wasm::WasmSymbolInfo Info;
const wasm::WasmSignature *Signature = nullptr;
const wasm::WasmGlobalType *GlobalType = nullptr;
const wasm::WasmTableType *TableType = nullptr;
Info.Kind = readUint8(Ctx);
Info.Flags = readVaruint32(Ctx);
bool IsDefined = (Info.Flags & wasm::WASM_SYMBOL_UNDEFINED) == 0;
switch (Info.Kind) {
case wasm::WASM_SYMBOL_TYPE_FUNCTION:
Info.ElementIndex = readVaruint32(Ctx);
if (!isValidFunctionIndex(Info.ElementIndex) ||
IsDefined != isDefinedFunctionIndex(Info.ElementIndex))
return make_error<GenericBinaryError>("invalid function symbol index",
object_error::parse_failed);
if (IsDefined) {
Info.Name = readString(Ctx);
unsigned FuncIndex = Info.ElementIndex - NumImportedFunctions;
wasm::WasmFunction &Function = Functions[FuncIndex];
Signature = &Signatures[Function.SigIndex];
if (Function.SymbolName.empty())
Function.SymbolName = Info.Name;
} else {
wasm::WasmImport &Import = *ImportedFunctions[Info.ElementIndex];
if ((Info.Flags & wasm::WASM_SYMBOL_EXPLICIT_NAME) != 0) {
Info.Name = readString(Ctx);
Info.ImportName = Import.Field;
} else {
Info.Name = Import.Field;
}
Signature = &Signatures[Import.SigIndex];
Info.ImportModule = Import.Module;
}
break;
case wasm::WASM_SYMBOL_TYPE_GLOBAL:
Info.ElementIndex = readVaruint32(Ctx);
if (!isValidGlobalIndex(Info.ElementIndex) ||
IsDefined != isDefinedGlobalIndex(Info.ElementIndex))
return make_error<GenericBinaryError>("invalid global symbol index",
object_error::parse_failed);
if (!IsDefined && (Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) ==
wasm::WASM_SYMBOL_BINDING_WEAK)
return make_error<GenericBinaryError>("undefined weak global symbol",
object_error::parse_failed);
if (IsDefined) {
Info.Name = readString(Ctx);
unsigned GlobalIndex = Info.ElementIndex - NumImportedGlobals;
wasm::WasmGlobal &Global = Globals[GlobalIndex];
GlobalType = &Global.Type;
if (Global.SymbolName.empty())
Global.SymbolName = Info.Name;
} else {
wasm::WasmImport &Import = *ImportedGlobals[Info.ElementIndex];
if ((Info.Flags & wasm::WASM_SYMBOL_EXPLICIT_NAME) != 0) {
Info.Name = readString(Ctx);
Info.ImportName = Import.Field;
} else {
Info.Name = Import.Field;
}
GlobalType = &Import.Global;
Info.ImportModule = Import.Module;
}
break;
case wasm::WASM_SYMBOL_TYPE_TABLE:
Info.ElementIndex = readVaruint32(Ctx);
if (!isValidTableNumber(Info.ElementIndex) ||
IsDefined != isDefinedTableNumber(Info.ElementIndex))
return make_error<GenericBinaryError>("invalid table symbol index",
object_error::parse_failed);
if (!IsDefined && (Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) ==
wasm::WASM_SYMBOL_BINDING_WEAK)
return make_error<GenericBinaryError>("undefined weak table symbol",
object_error::parse_failed);
if (IsDefined) {
Info.Name = readString(Ctx);
unsigned TableNumber = Info.ElementIndex - NumImportedTables;
wasm::WasmTable &Table = Tables[TableNumber];
TableType = &Table.Type;
if (Table.SymbolName.empty())
Table.SymbolName = Info.Name;
} else {
wasm::WasmImport &Import = *ImportedTables[Info.ElementIndex];
if ((Info.Flags & wasm::WASM_SYMBOL_EXPLICIT_NAME) != 0) {
Info.Name = readString(Ctx);
Info.ImportName = Import.Field;
} else {
Info.Name = Import.Field;
}
TableType = &Import.Table;
Info.ImportModule = Import.Module;
}
break;
case wasm::WASM_SYMBOL_TYPE_DATA:
Info.Name = readString(Ctx);
if (IsDefined) {
if ((Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) ==
wasm::WASM_SYMBOL_BINDING_COMMON) {
if (Info.Flags & wasm::WASM_SYMBOL_ABSOLUTE)
return make_error<GenericBinaryError>(
"common symbols cannot be absolute: " + Info.Name,
object_error::parse_failed);
auto Size = readVaruint64(Ctx);
auto Alignment = readUint8(Ctx);
if (Alignment > 32)
return make_error<GenericBinaryError>(
"invalid common symbol alignment: `" + Info.Name +
"` (alignment: " + Twine(unsigned(Alignment)) + ")",
object_error::parse_failed);
Info.CommonRef = wasm::WasmCommonReference{Size, Alignment};
} else {
auto Index = readVaruint32(Ctx);
auto Offset = readVaruint64(Ctx);
auto Size = readVaruint64(Ctx);
if (!(Info.Flags & wasm::WASM_SYMBOL_ABSOLUTE)) {
if (Index >= DataSegments.size())
return make_error<GenericBinaryError>(
"invalid data segment index: " + Twine(Index),
object_error::parse_failed);
size_t SegmentSize = DataSegments[Index].Data.Content.size();
if (Offset > SegmentSize)
return make_error<GenericBinaryError>(
"invalid data symbol offset: `" + Info.Name +
"` (offset: " + Twine(Offset) +
" segment size: " + Twine(SegmentSize) + ")",
object_error::parse_failed);
}
Info.DataRef = wasm::WasmDataReference{Index, Offset, Size};
}
}
break;
case wasm::WASM_SYMBOL_TYPE_SECTION: {
if ((Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) !=
wasm::WASM_SYMBOL_BINDING_LOCAL)
return make_error<GenericBinaryError>(
"section symbols must have local binding",
object_error::parse_failed);
Info.ElementIndex = readVaruint32(Ctx);
// Use somewhat unique section name as symbol name.
StringRef SectionName = Sections[Info.ElementIndex].Name;
Info.Name = SectionName;
break;
}
case wasm::WASM_SYMBOL_TYPE_TAG: {
Info.ElementIndex = readVaruint32(Ctx);
if (!isValidTagIndex(Info.ElementIndex) ||
IsDefined != isDefinedTagIndex(Info.ElementIndex))
return make_error<GenericBinaryError>("invalid tag symbol index",
object_error::parse_failed);
if (!IsDefined && (Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) ==
wasm::WASM_SYMBOL_BINDING_WEAK)
return make_error<GenericBinaryError>("undefined weak global symbol",
object_error::parse_failed);
if (IsDefined) {
Info.Name = readString(Ctx);
unsigned TagIndex = Info.ElementIndex - NumImportedTags;
wasm::WasmTag &Tag = Tags[TagIndex];
Signature = &Signatures[Tag.SigIndex];
if (Tag.SymbolName.empty())
Tag.SymbolName = Info.Name;
} else {
wasm::WasmImport &Import = *ImportedTags[Info.ElementIndex];
if ((Info.Flags & wasm::WASM_SYMBOL_EXPLICIT_NAME) != 0) {
Info.Name = readString(Ctx);
Info.ImportName = Import.Field;
} else {
Info.Name = Import.Field;
}
Signature = &Signatures[Import.SigIndex];
Info.ImportModule = Import.Module;
}
break;
}
default:
return make_error<GenericBinaryError>("invalid symbol type: " +
Twine(unsigned(Info.Kind)),
object_error::parse_failed);
}
if ((Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) !=
wasm::WASM_SYMBOL_BINDING_LOCAL &&
!SymbolNames.insert(Info.Name).second)
return make_error<GenericBinaryError>("duplicate symbol name " +
Twine(Info.Name),
object_error::parse_failed);
Symbols.emplace_back(Info, GlobalType, TableType, Signature);
LLVM_DEBUG(dbgs() << "Adding symbol: " << Symbols.back() << "\n");
}
return Error::success();
}
Error WasmObjectFile::parseLinkingSectionComdat(ReadContext &Ctx) {
uint32_t ComdatCount = readVaruint32(Ctx);
StringSet<> ComdatSet;
for (unsigned ComdatIndex = 0; ComdatIndex < ComdatCount; ++ComdatIndex) {
StringRef Name = readString(Ctx);
if (Name.empty() || !ComdatSet.insert(Name).second)
return make_error<GenericBinaryError>("bad/duplicate COMDAT name " +
Twine(Name),
object_error::parse_failed);
LinkingData.Comdats.emplace_back(Name);
uint32_t Flags = readVaruint32(Ctx);
if (Flags != 0)
return make_error<GenericBinaryError>("unsupported COMDAT flags",
object_error::parse_failed);
uint32_t EntryCount = readVaruint32(Ctx);
while (EntryCount--) {
unsigned Kind = readVaruint32(Ctx);
unsigned Index = readVaruint32(Ctx);
switch (Kind) {
default:
return make_error<GenericBinaryError>("invalid COMDAT entry type",
object_error::parse_failed);
case wasm::WASM_COMDAT_DATA:
if (Index >= DataSegments.size())
return make_error<GenericBinaryError>(
"COMDAT data index out of range", object_error::parse_failed);
if (DataSegments[Index].Data.Comdat != UINT32_MAX)
return make_error<GenericBinaryError>("data segment in two COMDATs",
object_error::parse_failed);
DataSegments[Index].Data.Comdat = ComdatIndex;
break;
case wasm::WASM_COMDAT_FUNCTION:
if (!isDefinedFunctionIndex(Index))
return make_error<GenericBinaryError>(
"COMDAT function index out of range", object_error::parse_failed);
if (getDefinedFunction(Index).Comdat != UINT32_MAX)
return make_error<GenericBinaryError>("function in two COMDATs",
object_error::parse_failed);
getDefinedFunction(Index).Comdat = ComdatIndex;
break;
case wasm::WASM_COMDAT_SECTION:
if (Index >= Sections.size())
return make_error<GenericBinaryError>(
"COMDAT section index out of range", object_error::parse_failed);
if (Sections[Index].Type != wasm::WASM_SEC_CUSTOM)
return make_error<GenericBinaryError>(
"non-custom section in a COMDAT", object_error::parse_failed);
Sections[Index].Comdat = ComdatIndex;
break;
}
}
}
return Error::success();
}
Error WasmObjectFile::parseProducersSection(ReadContext &Ctx) {
llvm::SmallSet<StringRef, 3> FieldsSeen;
uint32_t Fields = readVaruint32(Ctx);
for (size_t I = 0; I < Fields; ++I) {
StringRef FieldName = readString(Ctx);
if (!FieldsSeen.insert(FieldName).second)
return make_error<GenericBinaryError>(
"producers section does not have unique fields",
object_error::parse_failed);
std::vector<std::pair<std::string, std::string>> *ProducerVec = nullptr;
if (FieldName == "language") {
ProducerVec = &ProducerInfo.Languages;
} else if (FieldName == "processed-by") {
ProducerVec = &ProducerInfo.Tools;
} else if (FieldName == "sdk") {
ProducerVec = &ProducerInfo.SDKs;
} else {
return make_error<GenericBinaryError>(
"producers section field is not named one of language, processed-by, "
"or sdk",
object_error::parse_failed);
}
uint32_t ValueCount = readVaruint32(Ctx);
llvm::SmallSet<StringRef, 8> ProducersSeen;
for (size_t J = 0; J < ValueCount; ++J) {
StringRef Name = readString(Ctx);
StringRef Version = readString(Ctx);
if (!ProducersSeen.insert(Name).second) {
return make_error<GenericBinaryError>(
"producers section contains repeated producer",
object_error::parse_failed);
}
ProducerVec->emplace_back(std::string(Name), std::string(Version));
}
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("producers section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseTargetFeaturesSection(ReadContext &Ctx) {
llvm::SmallSet<std::string, 8> FeaturesSeen;
uint32_t FeatureCount = readVaruint32(Ctx);
for (size_t I = 0; I < FeatureCount; ++I) {
wasm::WasmFeatureEntry Feature;
Feature.Prefix = readUint8(Ctx);
switch (Feature.Prefix) {
case wasm::WASM_FEATURE_PREFIX_USED:
case wasm::WASM_FEATURE_PREFIX_DISALLOWED:
break;
default:
return make_error<GenericBinaryError>("unknown feature policy prefix",
object_error::parse_failed);
}
Feature.Name = std::string(readString(Ctx));
if (!FeaturesSeen.insert(Feature.Name).second)
return make_error<GenericBinaryError>(
"target features section contains repeated feature \"" +
Feature.Name + "\"",
object_error::parse_failed);
TargetFeatures.push_back(Feature);
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>(
"target features section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseRelocSection(StringRef Name, ReadContext &Ctx) {
uint32_t SectionIndex = readVaruint32(Ctx);
if (SectionIndex >= Sections.size())
return make_error<GenericBinaryError>("invalid section index",
object_error::parse_failed);
WasmSection &Section = Sections[SectionIndex];
uint32_t RelocCount = readVaruint32(Ctx);
uint32_t EndOffset = Section.Content.size();
uint32_t PreviousOffset = 0;
while (RelocCount--) {
wasm::WasmRelocation Reloc = {};
uint32_t type = readVaruint32(Ctx);
Reloc.Type = type;
Reloc.Offset = readVaruint32(Ctx);
if (Reloc.Offset < PreviousOffset)
return make_error<GenericBinaryError>("relocations not in offset order",
object_error::parse_failed);
auto badReloc = [&](StringRef msg) {
if (Reloc.Index >= Symbols.size())
return make_error<GenericBinaryError>(
msg + ": index " + Twine(Reloc.Index) + " out of range",
object_error::parse_failed);
return make_error<GenericBinaryError>(
msg + ": " + Twine(Symbols[Reloc.Index].Info.Name),
object_error::parse_failed);
};
PreviousOffset = Reloc.Offset;
Reloc.Index = readVaruint32(Ctx);
switch (type) {
case wasm::R_WASM_FUNCTION_INDEX_LEB:
case wasm::R_WASM_FUNCTION_INDEX_I32:
case wasm::R_WASM_TABLE_INDEX_SLEB:
case wasm::R_WASM_TABLE_INDEX_SLEB64:
case wasm::R_WASM_TABLE_INDEX_I32:
case wasm::R_WASM_TABLE_INDEX_I64:
case wasm::R_WASM_TABLE_INDEX_REL_SLEB:
case wasm::R_WASM_TABLE_INDEX_REL_SLEB64:
if (!isValidFunctionSymbol(Reloc.Index))
return badReloc("invalid function relocation");
break;
case wasm::R_WASM_TABLE_NUMBER_LEB:
if (!isValidTableSymbol(Reloc.Index))
return badReloc("invalid table relocation");
break;
case wasm::R_WASM_TYPE_INDEX_LEB:
if (Reloc.Index >= Signatures.size())
return badReloc("invalid relocation type index");
break;
case wasm::R_WASM_GLOBAL_INDEX_LEB:
// R_WASM_GLOBAL_INDEX_LEB are can be used against function and data
// symbols to refer to their GOT entries.
if (!isValidGlobalSymbol(Reloc.Index) &&
!isValidDataSymbol(Reloc.Index) &&
!isValidFunctionSymbol(Reloc.Index))
return badReloc("invalid global relocation");
break;
case wasm::R_WASM_GLOBAL_INDEX_I32:
if (!isValidGlobalSymbol(Reloc.Index))
return badReloc("invalid global relocation");
break;
case wasm::R_WASM_TAG_INDEX_LEB:
if (!isValidTagSymbol(Reloc.Index))
return badReloc("invalid tag relocation");
break;
case wasm::R_WASM_MEMORY_ADDR_LEB:
case wasm::R_WASM_MEMORY_ADDR_SLEB:
case wasm::R_WASM_MEMORY_ADDR_I32:
case wasm::R_WASM_MEMORY_ADDR_REL_SLEB:
case wasm::R_WASM_MEMORY_ADDR_TLS_SLEB:
case wasm::R_WASM_MEMORY_ADDR_LOCREL_I32:
if (!isValidDataSymbol(Reloc.Index))
return badReloc("invalid data relocation");
Reloc.Addend = readVarint32(Ctx);
break;
case wasm::R_WASM_MEMORY_ADDR_LEB64:
case wasm::R_WASM_MEMORY_ADDR_SLEB64:
case wasm::R_WASM_MEMORY_ADDR_I64:
case wasm::R_WASM_MEMORY_ADDR_REL_SLEB64:
case wasm::R_WASM_MEMORY_ADDR_TLS_SLEB64:
case wasm::R_WASM_MEMORY_ADDR_LOCREL_I64:
if (!isValidDataSymbol(Reloc.Index))
return badReloc("invalid data relocation");
Reloc.Addend = readVarint64(Ctx);
break;
case wasm::R_WASM_FUNCTION_OFFSET_I32:
if (!isValidFunctionSymbol(Reloc.Index))
return badReloc("invalid function relocation");
Reloc.Addend = readVarint32(Ctx);
break;
case wasm::R_WASM_FUNCTION_OFFSET_I64:
if (!isValidFunctionSymbol(Reloc.Index))
return badReloc("invalid function relocation");
Reloc.Addend = readVarint64(Ctx);
break;
case wasm::R_WASM_SECTION_OFFSET_I32:
if (!isValidSectionSymbol(Reloc.Index))
return badReloc("invalid section relocation");
Reloc.Addend = readVarint32(Ctx);
break;
default:
return make_error<GenericBinaryError>("invalid relocation type: " +
Twine(type),
object_error::parse_failed);
}
// Relocations must fit inside the section, and must appear in order. They
// also shouldn't overlap a function/element boundary, but we don't bother
// to check that.
uint64_t Size = 5;
if (Reloc.Type == wasm::R_WASM_MEMORY_ADDR_LEB64 ||
Reloc.Type == wasm::R_WASM_MEMORY_ADDR_SLEB64 ||
Reloc.Type == wasm::R_WASM_MEMORY_ADDR_REL_SLEB64)
Size = 10;
if (Reloc.Type == wasm::R_WASM_TABLE_INDEX_I32 ||
Reloc.Type == wasm::R_WASM_MEMORY_ADDR_I32 ||
Reloc.Type == wasm::R_WASM_MEMORY_ADDR_LOCREL_I32 ||
Reloc.Type == wasm::R_WASM_SECTION_OFFSET_I32 ||
Reloc.Type == wasm::R_WASM_FUNCTION_OFFSET_I32 ||
Reloc.Type == wasm::R_WASM_FUNCTION_INDEX_I32 ||
Reloc.Type == wasm::R_WASM_GLOBAL_INDEX_I32)
Size = 4;
if (Reloc.Type == wasm::R_WASM_TABLE_INDEX_I64 ||
Reloc.Type == wasm::R_WASM_MEMORY_ADDR_I64 ||
Reloc.Type == wasm::R_WASM_FUNCTION_OFFSET_I64 ||
Reloc.Type == wasm::R_WASM_MEMORY_ADDR_LOCREL_I64)
Size = 8;
if (Reloc.Offset + Size > EndOffset)
return make_error<GenericBinaryError>("invalid relocation offset",
object_error::parse_failed);
Section.Relocations.push_back(Reloc);
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("reloc section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseCustomSection(WasmSection &Sec, ReadContext &Ctx) {
if (Sec.Name == "dylink") {
if (Error Err = parseDylinkSection(Ctx))
return Err;
} else if (Sec.Name == "dylink.0") {
if (Error Err = parseDylink0Section(Ctx))
return Err;
} else if (Sec.Name == "name") {
if (Error Err = parseNameSection(Ctx))
return Err;
} else if (Sec.Name == "linking") {
if (Error Err = parseLinkingSection(Ctx))
return Err;
} else if (Sec.Name == "producers") {
if (Error Err = parseProducersSection(Ctx))
return Err;
} else if (Sec.Name == "target_features") {
if (Error Err = parseTargetFeaturesSection(Ctx))
return Err;
} else if (Sec.Name.starts_with("reloc.")) {
if (Error Err = parseRelocSection(Sec.Name, Ctx))
return Err;
}
return Error::success();
}
Error WasmObjectFile::parseTypeSection(ReadContext &Ctx) {
auto parseFieldDef = [&]() {
uint32_t TypeCode = readVaruint32((Ctx));
/* Discard StorageType */ parseValType(Ctx, TypeCode);
/* Discard Mutability */ readVaruint32(Ctx);
};
uint32_t Count = readVaruint32(Ctx);
Signatures.reserve(Count);
while (Count--) {
wasm::WasmSignature Sig;
uint8_t Form = readUint8(Ctx);
if (Form == wasm::WASM_TYPE_REC) {
// Rec groups expand the type index space (beyond what was declared at
// the top of the section, and also consume one element in that space.
uint32_t RecSize = readVaruint32(Ctx);
if (RecSize == 0)
return make_error<GenericBinaryError>("Rec group size cannot be 0",
object_error::parse_failed);
Signatures.reserve(Signatures.size() + RecSize);
Count += RecSize;
Sig.Kind = wasm::WasmSignature::Placeholder;
Signatures.push_back(std::move(Sig));
HasUnmodeledTypes = true;
continue;
}
if (Form != wasm::WASM_TYPE_FUNC) {
// Currently LLVM only models function types, and not other composite
// types. Here we parse the type declarations just enough to skip past
// them in the binary.
if (Form == wasm::WASM_TYPE_SUB || Form == wasm::WASM_TYPE_SUB_FINAL) {
uint32_t Supers = readVaruint32(Ctx);
if (Supers > 0) {
if (Supers != 1)
return make_error<GenericBinaryError>(
"Invalid number of supertypes", object_error::parse_failed);
/* Discard SuperIndex */ readVaruint32(Ctx);
}
Form = readVaruint32(Ctx);
}
if (Form == wasm::WASM_TYPE_STRUCT) {
uint32_t FieldCount = readVaruint32(Ctx);
while (FieldCount--) {
parseFieldDef();
}
} else if (Form == wasm::WASM_TYPE_ARRAY) {
parseFieldDef();
} else {
return make_error<GenericBinaryError>("bad form",
object_error::parse_failed);
}
Sig.Kind = wasm::WasmSignature::Placeholder;
Signatures.push_back(std::move(Sig));
HasUnmodeledTypes = true;
continue;
}
uint32_t ParamCount = readVaruint32(Ctx);
Sig.Params.reserve(ParamCount);
while (ParamCount--) {
uint32_t ParamType = readUint8(Ctx);
Sig.Params.push_back(parseValType(Ctx, ParamType));
}
uint32_t ReturnCount = readVaruint32(Ctx);
while (ReturnCount--) {
uint32_t ReturnType = readUint8(Ctx);
Sig.Returns.push_back(parseValType(Ctx, ReturnType));
}
Signatures.push_back(std::move(Sig));
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("type section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseImport(ReadContext &Ctx, wasm::WasmImport &Im) {
switch (Im.Kind) {
case wasm::WASM_EXTERNAL_FUNCTION:
NumImportedFunctions++;
Im.SigIndex = readVaruint32(Ctx);
if (Im.SigIndex >= Signatures.size())
return make_error<GenericBinaryError>("invalid function type",
object_error::parse_failed);
break;
case wasm::WASM_EXTERNAL_GLOBAL:
NumImportedGlobals++;
Im.Global.Type = readUint8(Ctx);
Im.Global.Mutable = readVaruint1(Ctx);
break;
case wasm::WASM_EXTERNAL_MEMORY:
Im.Memory = readLimits(Ctx);
if (Im.Memory.Flags & wasm::WASM_LIMITS_FLAG_IS_64)
HasMemory64 = true;
break;
case wasm::WASM_EXTERNAL_TABLE: {
Im.Table = readTableType(Ctx);
NumImportedTables++;
auto ElemType = Im.Table.ElemType;
if (ElemType != wasm::ValType::FUNCREF &&
ElemType != wasm::ValType::EXTERNREF &&
ElemType != wasm::ValType::EXNREF &&
ElemType != wasm::ValType::OTHERREF)
return make_error<GenericBinaryError>("invalid table element type",
object_error::parse_failed);
break;
}
case wasm::WASM_EXTERNAL_TAG:
NumImportedTags++;
if (readUint8(Ctx) != 0) // Reserved 'attribute' field
return make_error<GenericBinaryError>("invalid attribute",
object_error::parse_failed);
Im.SigIndex = readVaruint32(Ctx);
if (Im.SigIndex >= Signatures.size())
return make_error<GenericBinaryError>("invalid tag type",
object_error::parse_failed);
break;
default:
return make_error<GenericBinaryError>("unexpected import kind: " +
Twine(unsigned(Im.Kind)),
object_error::parse_failed);
}
Imports.push_back(Im);
return Error::success();
}
Error WasmObjectFile::parseImportSection(ReadContext &Ctx) {
uint32_t Count = readVaruint32(Ctx);
Imports.reserve(Count);
uint32_t I = 0;
while (I < Count) {
wasm::WasmImport Im;
Im.Module = readString(Ctx);
Im.Field = readString(Ctx);
Im.Kind = readUint8(Ctx);
// 0x7E/0x7F along with an empty Field signals a block of compact imports.
if (Im.Kind == 0x7E && Im.Field == "") {
return make_error<GenericBinaryError>(
"compact import format (0x7E) is not yet supported",
object_error::parse_failed);
} else if (Im.Kind == 0x7F && Im.Field == "") {
uint32_t NumCompactImports = readVaruint32(Ctx);
while (NumCompactImports--) {
Im.Field = readString(Ctx);
Im.Kind = readUint8(Ctx);
Error rtn = parseImport(Ctx, Im);
if (rtn)
return rtn;
I++;
}
} else {
Error rtn = parseImport(Ctx, Im);
if (rtn)
return rtn;
I++;
}
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("import section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseFunctionSection(ReadContext &Ctx) {
uint32_t Count = readVaruint32(Ctx);
Functions.reserve(Count);
uint32_t NumTypes = Signatures.size();
while (Count--) {
uint32_t Type = readVaruint32(Ctx);
if (Type >= NumTypes)
return make_error<GenericBinaryError>("invalid function type",
object_error::parse_failed);
wasm::WasmFunction F;
F.SigIndex = Type;
Functions.push_back(F);
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("function section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseTableSection(ReadContext &Ctx) {
TableSection = Sections.size();
uint32_t Count = readVaruint32(Ctx);
Tables.reserve(Count);
while (Count--) {
wasm::WasmTable T;
T.Type = readTableType(Ctx);
T.Index = NumImportedTables + Tables.size();
Tables.push_back(T);
auto ElemType = Tables.back().Type.ElemType;
if (ElemType != wasm::ValType::FUNCREF &&
ElemType != wasm::ValType::EXTERNREF &&
ElemType != wasm::ValType::EXNREF &&
ElemType != wasm::ValType::OTHERREF) {
return make_error<GenericBinaryError>("invalid table element type",
object_error::parse_failed);
}
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("table section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseMemorySection(ReadContext &Ctx) {
uint32_t Count = readVaruint32(Ctx);
Memories.reserve(Count);
while (Count--) {
auto Limits = readLimits(Ctx);
if (Limits.Flags & wasm::WASM_LIMITS_FLAG_IS_64)
HasMemory64 = true;
Memories.push_back(Limits);
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("memory section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseTagSection(ReadContext &Ctx) {
TagSection = Sections.size();
uint32_t Count = readVaruint32(Ctx);
Tags.reserve(Count);
uint32_t NumTypes = Signatures.size();
while (Count--) {
if (readUint8(Ctx) != 0) // Reserved 'attribute' field
return make_error<GenericBinaryError>("invalid attribute",
object_error::parse_failed);
uint32_t Type = readVaruint32(Ctx);
if (Type >= NumTypes)
return make_error<GenericBinaryError>("invalid tag type",
object_error::parse_failed);
wasm::WasmTag Tag;
Tag.Index = NumImportedTags + Tags.size();
Tag.SigIndex = Type;
Signatures[Type].Kind = wasm::WasmSignature::Tag;
Tags.push_back(Tag);
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("tag section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseGlobalSection(ReadContext &Ctx) {
GlobalSection = Sections.size();
const uint8_t *SectionStart = Ctx.Ptr;
uint32_t Count = readVaruint32(Ctx);
Globals.reserve(Count);
while (Count--) {
wasm::WasmGlobal Global;
Global.Index = NumImportedGlobals + Globals.size();
const uint8_t *GlobalStart = Ctx.Ptr;
Global.Offset = static_cast<uint32_t>(GlobalStart - SectionStart);
auto GlobalOpcode = readVaruint32(Ctx);
Global.Type.Type = (uint8_t)parseValType(Ctx, GlobalOpcode);
Global.Type.Mutable = readVaruint1(Ctx);
if (Error Err = readInitExpr(Global.InitExpr, Ctx))
return Err;
Global.Size = static_cast<uint32_t>(Ctx.Ptr - GlobalStart);
Globals.push_back(Global);
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("global section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseExportSection(ReadContext &Ctx) {
uint32_t Count = readVaruint32(Ctx);
Exports.reserve(Count);
Symbols.reserve(Count);
// Build hash map of export flags for faster cross-referencing
llvm::DenseMap<StringRef, uint32_t> ExportFlags;
if (HasDylinkSection) {
for (const auto &ExportInfo : DylinkInfo.ExportInfo) {
ExportFlags[ExportInfo.Name] = ExportInfo.Flags;
}
}
for (uint32_t I = 0; I < Count; I++) {
wasm::WasmExport Ex;
Ex.Name = readString(Ctx);
Ex.Kind = readUint8(Ctx);
Ex.Index = readVaruint32(Ctx);
const wasm::WasmSignature *Signature = nullptr;
const wasm::WasmGlobalType *GlobalType = nullptr;
const wasm::WasmTableType *TableType = nullptr;
wasm::WasmSymbolInfo Info;
Info.Name = Ex.Name;
Info.Flags = 0;
// For shared objects, symbol flags may be specified in the dylink section
// instead of the export section
if (HasDylinkSection) {
auto It = ExportFlags.find(Ex.Name);
if (It != ExportFlags.end()) {
Info.Flags = It->second;
}
}
switch (Ex.Kind) {
case wasm::WASM_EXTERNAL_FUNCTION: {
if (!isValidFunctionIndex(Ex.Index))
return make_error<GenericBinaryError>("invalid function export",
object_error::parse_failed);
Info.Kind = wasm::WASM_SYMBOL_TYPE_FUNCTION;
Info.ElementIndex = Ex.Index;
if (isDefinedFunctionIndex(Ex.Index)) {
getDefinedFunction(Ex.Index).ExportName = Ex.Name;
unsigned FuncIndex = Info.ElementIndex - NumImportedFunctions;
wasm::WasmFunction &Function = Functions[FuncIndex];
Signature = &Signatures[Function.SigIndex];
}
// Else the function is imported. LLVM object files don't use this
// pattern and we still treat this as an undefined symbol, but we want to
// parse it without crashing.
break;
}
case wasm::WASM_EXTERNAL_GLOBAL: {
if (!isValidGlobalIndex(Ex.Index))
return make_error<GenericBinaryError>("invalid global export",
object_error::parse_failed);
Info.Kind = wasm::WASM_SYMBOL_TYPE_DATA;
uint64_t Offset = 0;
if (isDefinedGlobalIndex(Ex.Index)) {
auto Global = getDefinedGlobal(Ex.Index);
if (!Global.InitExpr.Extended) {
auto Inst = Global.InitExpr.Inst;
if (Inst.Opcode == wasm::WASM_OPCODE_I32_CONST) {
Offset = Inst.Value.Int32;
} else if (Inst.Opcode == wasm::WASM_OPCODE_I64_CONST) {
Offset = Inst.Value.Int64;
}
}
}
Info.DataRef = wasm::WasmDataReference{0, Offset, 0};
break;
}
case wasm::WASM_EXTERNAL_TAG:
if (!isValidTagIndex(Ex.Index))
return make_error<GenericBinaryError>("invalid tag export",
object_error::parse_failed);
Info.Kind = wasm::WASM_SYMBOL_TYPE_TAG;
Info.ElementIndex = Ex.Index;
if (isDefinedTagIndex(Ex.Index)) {
unsigned TagIndex = Ex.Index - NumImportedTags;
Signature = &Signatures[Tags[TagIndex].SigIndex];
}
break;
case wasm::WASM_EXTERNAL_MEMORY:
break;
case wasm::WASM_EXTERNAL_TABLE:
Info.Kind = wasm::WASM_SYMBOL_TYPE_TABLE;
Info.ElementIndex = Ex.Index;
break;
default:
return make_error<GenericBinaryError>("unexpected export kind",
object_error::parse_failed);
}
Exports.push_back(Ex);
if (Ex.Kind != wasm::WASM_EXTERNAL_MEMORY) {
Symbols.emplace_back(Info, GlobalType, TableType, Signature);
LLVM_DEBUG(dbgs() << "Adding symbol: " << Symbols.back() << "\n");
}
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("export section ended prematurely",
object_error::parse_failed);
return Error::success();
}
bool WasmObjectFile::isValidFunctionIndex(uint32_t Index) const {
return Index < NumImportedFunctions + Functions.size();
}
bool WasmObjectFile::isDefinedFunctionIndex(uint32_t Index) const {
return Index >= NumImportedFunctions && isValidFunctionIndex(Index);
}
bool WasmObjectFile::isValidGlobalIndex(uint32_t Index) const {
return Index < NumImportedGlobals + Globals.size();
}
bool WasmObjectFile::isValidTableNumber(uint32_t Index) const {
return Index < NumImportedTables + Tables.size();
}
bool WasmObjectFile::isDefinedGlobalIndex(uint32_t Index) const {
return Index >= NumImportedGlobals && isValidGlobalIndex(Index);
}
bool WasmObjectFile::isDefinedTableNumber(uint32_t Index) const {
return Index >= NumImportedTables && isValidTableNumber(Index);
}
bool WasmObjectFile::isValidTagIndex(uint32_t Index) const {
return Index < NumImportedTags + Tags.size();
}
bool WasmObjectFile::isDefinedTagIndex(uint32_t Index) const {
return Index >= NumImportedTags && isValidTagIndex(Index);
}
bool WasmObjectFile::isValidFunctionSymbol(uint32_t Index) const {
return Index < Symbols.size() && Symbols[Index].isTypeFunction();
}
bool WasmObjectFile::isValidTableSymbol(uint32_t Index) const {
return Index < Symbols.size() && Symbols[Index].isTypeTable();
}
bool WasmObjectFile::isValidGlobalSymbol(uint32_t Index) const {
return Index < Symbols.size() && Symbols[Index].isTypeGlobal();
}
bool WasmObjectFile::isValidTagSymbol(uint32_t Index) const {
return Index < Symbols.size() && Symbols[Index].isTypeTag();
}
bool WasmObjectFile::isValidDataSymbol(uint32_t Index) const {
return Index < Symbols.size() && Symbols[Index].isTypeData();
}
bool WasmObjectFile::isValidSectionSymbol(uint32_t Index) const {
return Index < Symbols.size() && Symbols[Index].isTypeSection();
}
wasm::WasmFunction &WasmObjectFile::getDefinedFunction(uint32_t Index) {
assert(isDefinedFunctionIndex(Index));
return Functions[Index - NumImportedFunctions];
}
const wasm::WasmFunction &
WasmObjectFile::getDefinedFunction(uint32_t Index) const {
assert(isDefinedFunctionIndex(Index));
return Functions[Index - NumImportedFunctions];
}
const wasm::WasmGlobal &WasmObjectFile::getDefinedGlobal(uint32_t Index) const {
assert(isDefinedGlobalIndex(Index));
return Globals[Index - NumImportedGlobals];
}
wasm::WasmTag &WasmObjectFile::getDefinedTag(uint32_t Index) {
assert(isDefinedTagIndex(Index));
return Tags[Index - NumImportedTags];
}
Error WasmObjectFile::parseStartSection(ReadContext &Ctx) {
StartFunction = readVaruint32(Ctx);
if (!isValidFunctionIndex(StartFunction))
return make_error<GenericBinaryError>("invalid start function",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseCodeSection(ReadContext &Ctx) {
CodeSection = Sections.size();
uint32_t FunctionCount = readVaruint32(Ctx);
if (FunctionCount != Functions.size()) {
return make_error<GenericBinaryError>("invalid function count",
object_error::parse_failed);
}
for (uint32_t i = 0; i < FunctionCount; i++) {
wasm::WasmFunction& Function = Functions[i];
const uint8_t *FunctionStart = Ctx.Ptr;
uint32_t Size = readVaruint32(Ctx);
const uint8_t *FunctionEnd = Ctx.Ptr + Size;
Function.CodeOffset = Ctx.Ptr - FunctionStart;
Function.Index = NumImportedFunctions + i;
Function.CodeSectionOffset = FunctionStart - Ctx.Start;
Function.Size = FunctionEnd - FunctionStart;
uint32_t NumLocalDecls = readVaruint32(Ctx);
Function.Locals.reserve(NumLocalDecls);
while (NumLocalDecls--) {
wasm::WasmLocalDecl Decl;
Decl.Count = readVaruint32(Ctx);
Decl.Type = readUint8(Ctx);
Function.Locals.push_back(Decl);
}
uint32_t BodySize = FunctionEnd - Ctx.Ptr;
// Ensure that Function is within Ctx's buffer.
if (Ctx.Ptr + BodySize > Ctx.End) {
return make_error<GenericBinaryError>("Function extends beyond buffer",
object_error::parse_failed);
}
Function.Body = ArrayRef<uint8_t>(Ctx.Ptr, BodySize);
// This will be set later when reading in the linking metadata section.
Function.Comdat = UINT32_MAX;
Ctx.Ptr += BodySize;
assert(Ctx.Ptr == FunctionEnd);
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("code section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseElemSection(ReadContext &Ctx) {
uint32_t Count = readVaruint32(Ctx);
ElemSegments.reserve(Count);
while (Count--) {
wasm::WasmElemSegment Segment;
Segment.Flags = readVaruint32(Ctx);
uint32_t SupportedFlags = wasm::WASM_ELEM_SEGMENT_HAS_TABLE_NUMBER |
wasm::WASM_ELEM_SEGMENT_IS_PASSIVE |
wasm::WASM_ELEM_SEGMENT_HAS_INIT_EXPRS;
if (Segment.Flags & ~SupportedFlags)
return make_error<GenericBinaryError>(
"Unsupported flags for element segment", object_error::parse_failed);
wasm::ElemSegmentMode Mode;
if ((Segment.Flags & wasm::WASM_ELEM_SEGMENT_IS_PASSIVE) == 0) {
Mode = wasm::ElemSegmentMode::Active;
} else if (Segment.Flags & wasm::WASM_ELEM_SEGMENT_IS_DECLARATIVE) {
Mode = wasm::ElemSegmentMode::Declarative;
} else {
Mode = wasm::ElemSegmentMode::Passive;
}
bool HasTableNumber =
Mode == wasm::ElemSegmentMode::Active &&
(Segment.Flags & wasm::WASM_ELEM_SEGMENT_HAS_TABLE_NUMBER);
bool HasElemKind =
(Segment.Flags & wasm::WASM_ELEM_SEGMENT_MASK_HAS_ELEM_DESC) &&
!(Segment.Flags & wasm::WASM_ELEM_SEGMENT_HAS_INIT_EXPRS);
bool HasElemType =
(Segment.Flags & wasm::WASM_ELEM_SEGMENT_MASK_HAS_ELEM_DESC) &&
(Segment.Flags & wasm::WASM_ELEM_SEGMENT_HAS_INIT_EXPRS);
bool HasInitExprs =
(Segment.Flags & wasm::WASM_ELEM_SEGMENT_HAS_INIT_EXPRS);
if (HasTableNumber)
Segment.TableNumber = readVaruint32(Ctx);
else
Segment.TableNumber = 0;
if (!isValidTableNumber(Segment.TableNumber))
return make_error<GenericBinaryError>("invalid TableNumber",
object_error::parse_failed);
if (Mode != wasm::ElemSegmentMode::Active) {
Segment.Offset.Extended = false;
Segment.Offset.Inst.Opcode = wasm::WASM_OPCODE_I32_CONST;
Segment.Offset.Inst.Value.Int32 = 0;
} else {
if (Error Err = readInitExpr(Segment.Offset, Ctx))
return Err;
}
if (HasElemKind) {
auto ElemKind = readVaruint32(Ctx);
if (Segment.Flags & wasm::WASM_ELEM_SEGMENT_HAS_INIT_EXPRS) {
Segment.ElemKind = parseValType(Ctx, ElemKind);
if (Segment.ElemKind != wasm::ValType::FUNCREF &&
Segment.ElemKind != wasm::ValType::EXTERNREF &&
Segment.ElemKind != wasm::ValType::EXNREF &&
Segment.ElemKind != wasm::ValType::OTHERREF) {
return make_error<GenericBinaryError>("invalid elem type",
object_error::parse_failed);
}
} else {
if (ElemKind != 0)
return make_error<GenericBinaryError>("invalid elem type",
object_error::parse_failed);
Segment.ElemKind = wasm::ValType::FUNCREF;
}
} else if (HasElemType) {
auto ElemType = parseValType(Ctx, readVaruint32(Ctx));
Segment.ElemKind = ElemType;
} else {
Segment.ElemKind = wasm::ValType::FUNCREF;
}
uint32_t NumElems = readVaruint32(Ctx);
if (HasInitExprs) {
while (NumElems--) {
wasm::WasmInitExpr Expr;
if (Error Err = readInitExpr(Expr, Ctx))
return Err;
}
} else {
while (NumElems--) {
Segment.Functions.push_back(readVaruint32(Ctx));
}
}
ElemSegments.push_back(Segment);
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("elem section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseDataSection(ReadContext &Ctx) {
DataSection = Sections.size();
uint32_t Count = readVaruint32(Ctx);
if (DataCount && Count != *DataCount)
return make_error<GenericBinaryError>(
"number of data segments does not match DataCount section");
DataSegments.reserve(Count);
while (Count--) {
WasmSegment Segment;
Segment.Data.InitFlags = readVaruint32(Ctx);
Segment.Data.MemoryIndex =
(Segment.Data.InitFlags & wasm::WASM_DATA_SEGMENT_HAS_MEMINDEX)
? readVaruint32(Ctx)
: 0;
if ((Segment.Data.InitFlags & wasm::WASM_DATA_SEGMENT_IS_PASSIVE) == 0) {
if (Error Err = readInitExpr(Segment.Data.Offset, Ctx))
return Err;
} else {
Segment.Data.Offset.Extended = false;
Segment.Data.Offset.Inst.Opcode = wasm::WASM_OPCODE_I32_CONST;
Segment.Data.Offset.Inst.Value.Int32 = 0;
}
uint32_t Size = readVaruint32(Ctx);
if (Size > (size_t)(Ctx.End - Ctx.Ptr))
return make_error<GenericBinaryError>("invalid segment size",
object_error::parse_failed);
Segment.Data.Content = ArrayRef<uint8_t>(Ctx.Ptr, Size);
// The rest of these Data fields are set later, when reading in the linking
// metadata section.
Segment.Data.Alignment = 0;
Segment.Data.LinkingFlags = 0;
Segment.Data.Comdat = UINT32_MAX;
Segment.SectionOffset = Ctx.Ptr - Ctx.Start;
Ctx.Ptr += Size;
DataSegments.push_back(Segment);
}
if (Ctx.Ptr != Ctx.End)
return make_error<GenericBinaryError>("data section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseDataCountSection(ReadContext &Ctx) {
DataCount = readVaruint32(Ctx);
return Error::success();
}
const wasm::WasmObjectHeader &WasmObjectFile::getHeader() const {
return Header;
}
void WasmObjectFile::moveSymbolNext(DataRefImpl &Symb) const { Symb.d.b++; }
Expected<uint32_t> WasmObjectFile::getSymbolFlags(DataRefImpl Symb) const {
uint32_t Result = SymbolRef::SF_None;
const WasmSymbol &Sym = getWasmSymbol(Symb);
LLVM_DEBUG(dbgs() << "getSymbolFlags: ptr=" << &Sym << " " << Sym << "\n");
if (Sym.isBindingWeak())
Result |= SymbolRef::SF_Weak;
if (!Sym.isBindingLocal())
Result |= SymbolRef::SF_Global;
if (Sym.isHidden())
Result |= SymbolRef::SF_Hidden;
if (!Sym.isDefined())
Result |= SymbolRef::SF_Undefined;
if (Sym.isTypeFunction())
Result |= SymbolRef::SF_Executable;
return Result;
}
basic_symbol_iterator WasmObjectFile::symbol_begin() const {
DataRefImpl Ref;
Ref.d.a = 1; // Arbitrary non-zero value so that Ref.p is non-null
Ref.d.b = 0; // Symbol index
return BasicSymbolRef(Ref, this);
}
basic_symbol_iterator WasmObjectFile::symbol_end() const {
DataRefImpl Ref;
Ref.d.a = 1; // Arbitrary non-zero value so that Ref.p is non-null
Ref.d.b = Symbols.size(); // Symbol index
return BasicSymbolRef(Ref, this);
}
const WasmSymbol &WasmObjectFile::getWasmSymbol(const DataRefImpl &Symb) const {
return Symbols[Symb.d.b];
}
const WasmSymbol &WasmObjectFile::getWasmSymbol(const SymbolRef &Symb) const {
return getWasmSymbol(Symb.getRawDataRefImpl());
}
Expected<StringRef> WasmObjectFile::getSymbolName(DataRefImpl Symb) const {
return getWasmSymbol(Symb).Info.Name;
}
Expected<uint64_t> WasmObjectFile::getSymbolAddress(DataRefImpl Symb) const {
auto &Sym = getWasmSymbol(Symb);
if (!Sym.isDefined())
return 0;
Expected<section_iterator> Sec = getSymbolSection(Symb);
if (!Sec)
return Sec.takeError();
uint32_t SectionAddress = getSectionAddress(Sec.get()->getRawDataRefImpl());
if (Sym.Info.Kind == wasm::WASM_SYMBOL_TYPE_FUNCTION &&
isDefinedFunctionIndex(Sym.Info.ElementIndex)) {
return getDefinedFunction(Sym.Info.ElementIndex).CodeSectionOffset +
SectionAddress;
}
if (Sym.Info.Kind == wasm::WASM_SYMBOL_TYPE_GLOBAL &&
isDefinedGlobalIndex(Sym.Info.ElementIndex)) {
return getDefinedGlobal(Sym.Info.ElementIndex).Offset + SectionAddress;
}
return getSymbolValue(Symb);
}
uint64_t WasmObjectFile::getWasmSymbolValue(const WasmSymbol &Sym) const {
switch (Sym.Info.Kind) {
case wasm::WASM_SYMBOL_TYPE_FUNCTION:
case wasm::WASM_SYMBOL_TYPE_GLOBAL:
case wasm::WASM_SYMBOL_TYPE_TAG:
case wasm::WASM_SYMBOL_TYPE_TABLE:
return Sym.Info.ElementIndex;
case wasm::WASM_SYMBOL_TYPE_DATA: {
// The value of a data symbol is the segment offset, plus the symbol
// offset within the segment.
uint32_t SegmentIndex = Sym.Info.DataRef.Segment;
const wasm::WasmDataSegment &Segment = DataSegments[SegmentIndex].Data;
if (Segment.Offset.Extended) {
llvm_unreachable("extended init exprs not supported");
} else if (Segment.Offset.Inst.Opcode == wasm::WASM_OPCODE_I32_CONST) {
return Segment.Offset.Inst.Value.Int32 + Sym.Info.DataRef.Offset;
} else if (Segment.Offset.Inst.Opcode == wasm::WASM_OPCODE_I64_CONST) {
return Segment.Offset.Inst.Value.Int64 + Sym.Info.DataRef.Offset;
} else if (Segment.Offset.Inst.Opcode == wasm::WASM_OPCODE_GLOBAL_GET) {
return Sym.Info.DataRef.Offset;
} else {
llvm_unreachable("unknown init expr opcode");
}
}
case wasm::WASM_SYMBOL_TYPE_SECTION:
return 0;
}
llvm_unreachable("invalid symbol type");
}
uint64_t WasmObjectFile::getSymbolValueImpl(DataRefImpl Symb) const {
return getWasmSymbolValue(getWasmSymbol(Symb));
}
uint32_t WasmObjectFile::getSymbolAlignment(DataRefImpl Symb) const {
llvm_unreachable("not yet implemented");
return 0;
}
uint64_t WasmObjectFile::getCommonSymbolSizeImpl(DataRefImpl Symb) const {
llvm_unreachable("not yet implemented");
return 0;
}
Expected<SymbolRef::Type>
WasmObjectFile::getSymbolType(DataRefImpl Symb) const {
const WasmSymbol &Sym = getWasmSymbol(Symb);
switch (Sym.Info.Kind) {
case wasm::WASM_SYMBOL_TYPE_FUNCTION:
return SymbolRef::ST_Function;
case wasm::WASM_SYMBOL_TYPE_GLOBAL:
return SymbolRef::ST_Other;
case wasm::WASM_SYMBOL_TYPE_DATA:
return SymbolRef::ST_Data;
case wasm::WASM_SYMBOL_TYPE_SECTION:
return SymbolRef::ST_Debug;
case wasm::WASM_SYMBOL_TYPE_TAG:
return SymbolRef::ST_Other;
case wasm::WASM_SYMBOL_TYPE_TABLE:
return SymbolRef::ST_Other;
}
llvm_unreachable("unknown WasmSymbol::SymbolType");
return SymbolRef::ST_Other;
}
Expected<section_iterator>
WasmObjectFile::getSymbolSection(DataRefImpl Symb) const {
const WasmSymbol &Sym = getWasmSymbol(Symb);
if (Sym.isUndefined())
return section_end();
DataRefImpl Ref;
Ref.d.a = getSymbolSectionIdImpl(Sym);
return section_iterator(SectionRef(Ref, this));
}
uint32_t WasmObjectFile::getSymbolSectionId(SymbolRef Symb) const {
const WasmSymbol &Sym = getWasmSymbol(Symb);
return getSymbolSectionIdImpl(Sym);
}
uint32_t WasmObjectFile::getSymbolSectionIdImpl(const WasmSymbol &Sym) const {
switch (Sym.Info.Kind) {
case wasm::WASM_SYMBOL_TYPE_FUNCTION:
return CodeSection;
case wasm::WASM_SYMBOL_TYPE_GLOBAL:
return GlobalSection;
case wasm::WASM_SYMBOL_TYPE_DATA:
return DataSection;
case wasm::WASM_SYMBOL_TYPE_SECTION:
return Sym.Info.ElementIndex;
case wasm::WASM_SYMBOL_TYPE_TAG:
return TagSection;
case wasm::WASM_SYMBOL_TYPE_TABLE:
return TableSection;
default:
llvm_unreachable("unknown WasmSymbol::SymbolType");
}
}
uint32_t WasmObjectFile::getSymbolSize(SymbolRef Symb) const {
const WasmSymbol &Sym = getWasmSymbol(Symb);
if (!Sym.isDefined())
return 0;
if (Sym.isTypeGlobal())
return getDefinedGlobal(Sym.Info.ElementIndex).Size;
if (Sym.isTypeData())
return Sym.Info.DataRef.Size;
if (Sym.isTypeFunction())
return functions()[Sym.Info.ElementIndex - getNumImportedFunctions()].Size;
// Currently symbol size is only tracked for data segments and functions. In
// principle we could also track size (e.g. binary size) for tables, globals
// and element segments etc too.
return 0;
}
void WasmObjectFile::moveSectionNext(DataRefImpl &Sec) const { Sec.d.a++; }
Expected<StringRef> WasmObjectFile::getSectionName(DataRefImpl Sec) const {
const WasmSection &S = Sections[Sec.d.a];
if (S.Type == wasm::WASM_SEC_CUSTOM)
return S.Name;
if (S.Type > wasm::WASM_SEC_LAST_KNOWN)
return createStringError(object_error::invalid_section_index, "");
return wasm::sectionTypeToString(S.Type);
}
uint64_t WasmObjectFile::getSectionAddress(DataRefImpl Sec) const {
// For object files, use 0 for section addresses, and section offsets for
// symbol addresses. For linked files, use file offsets.
// See also getSymbolAddress.
return isRelocatableObject() || isSharedObject() ? 0
: Sections[Sec.d.a].Offset;
}
uint64_t WasmObjectFile::getSectionIndex(DataRefImpl Sec) const {
return Sec.d.a;
}
uint64_t WasmObjectFile::getSectionSize(DataRefImpl Sec) const {
const WasmSection &S = Sections[Sec.d.a];
return S.Content.size();
}
Expected<ArrayRef<uint8_t>>
WasmObjectFile::getSectionContents(DataRefImpl Sec) const {
const WasmSection &S = Sections[Sec.d.a];
// This will never fail since wasm sections can never be empty (user-sections
// must have a name and non-user sections each have a defined structure).
return S.Content;
}
uint64_t WasmObjectFile::getSectionAlignment(DataRefImpl Sec) const {
return 1;
}
bool WasmObjectFile::isSectionCompressed(DataRefImpl Sec) const {
return false;
}
bool WasmObjectFile::isSectionText(DataRefImpl Sec) const {
return getWasmSection(Sec).Type == wasm::WASM_SEC_CODE;
}
bool WasmObjectFile::isSectionData(DataRefImpl Sec) const {
return getWasmSection(Sec).Type == wasm::WASM_SEC_DATA;
}
bool WasmObjectFile::isSectionBSS(DataRefImpl Sec) const { return false; }
bool WasmObjectFile::isSectionVirtual(DataRefImpl Sec) const { return false; }
relocation_iterator WasmObjectFile::section_rel_begin(DataRefImpl Ref) const {
DataRefImpl RelocRef;
RelocRef.d.a = Ref.d.a;
RelocRef.d.b = 0;
return relocation_iterator(RelocationRef(RelocRef, this));
}
relocation_iterator WasmObjectFile::section_rel_end(DataRefImpl Ref) const {
const WasmSection &Sec = getWasmSection(Ref);
DataRefImpl RelocRef;
RelocRef.d.a = Ref.d.a;
RelocRef.d.b = Sec.Relocations.size();
return relocation_iterator(RelocationRef(RelocRef, this));
}
void WasmObjectFile::moveRelocationNext(DataRefImpl &Rel) const { Rel.d.b++; }
uint64_t WasmObjectFile::getRelocationOffset(DataRefImpl Ref) const {
const wasm::WasmRelocation &Rel = getWasmRelocation(Ref);
return Rel.Offset;
}
symbol_iterator WasmObjectFile::getRelocationSymbol(DataRefImpl Ref) const {
const wasm::WasmRelocation &Rel = getWasmRelocation(Ref);
if (Rel.Type == wasm::R_WASM_TYPE_INDEX_LEB)
return symbol_end();
DataRefImpl Sym;
Sym.d.a = 1;
Sym.d.b = Rel.Index;
return symbol_iterator(SymbolRef(Sym, this));
}
uint64_t WasmObjectFile::getRelocationType(DataRefImpl Ref) const {
const wasm::WasmRelocation &Rel = getWasmRelocation(Ref);
return Rel.Type;
}
void WasmObjectFile::getRelocationTypeName(
DataRefImpl Ref, SmallVectorImpl<char> &Result) const {
const wasm::WasmRelocation &Rel = getWasmRelocation(Ref);
StringRef Res = "Unknown";
#define WASM_RELOC(name, value) \
case wasm::name: \
Res = #name; \
break;
switch (Rel.Type) {
#include "llvm/BinaryFormat/WasmRelocs.def"
}
#undef WASM_RELOC
Result.append(Res.begin(), Res.end());
}
section_iterator WasmObjectFile::section_begin() const {
DataRefImpl Ref;
Ref.d.a = 0;
return section_iterator(SectionRef(Ref, this));
}
section_iterator WasmObjectFile::section_end() const {
DataRefImpl Ref;
Ref.d.a = Sections.size();
return section_iterator(SectionRef(Ref, this));
}
uint8_t WasmObjectFile::getBytesInAddress() const {
return getArch() == Triple::wasm64 ? 8 : 4;
}
StringRef WasmObjectFile::getFileFormatName() const { return "WASM"; }
Triple::ArchType WasmObjectFile::getArch() const {
if (!LinkingData.TargetArch.empty())
return Triple(LinkingData.TargetArch).getArch();
if (!DylinkInfo.TargetArch.empty())
return Triple(DylinkInfo.TargetArch).getArch();
// Fall back to the HasMemory64 heuristic for backwards compatibility with
// older object files/shared libraries that lack target architecture metadata,
// as well as final executables that lack custom linking/dylink sections.
return HasMemory64 ? Triple::wasm64 : Triple::wasm32;
}
Expected<SubtargetFeatures> WasmObjectFile::getFeatures() const {
return SubtargetFeatures();
}
bool WasmObjectFile::isRelocatableObject() const { return HasLinkingSection; }
bool WasmObjectFile::isSharedObject() const { return HasDylinkSection; }
const WasmSection &WasmObjectFile::getWasmSection(DataRefImpl Ref) const {
assert(Ref.d.a < Sections.size());
return Sections[Ref.d.a];
}
const WasmSection &
WasmObjectFile::getWasmSection(const SectionRef &Section) const {
return getWasmSection(Section.getRawDataRefImpl());
}
const wasm::WasmRelocation &
WasmObjectFile::getWasmRelocation(const RelocationRef &Ref) const {
return getWasmRelocation(Ref.getRawDataRefImpl());
}
const wasm::WasmRelocation &
WasmObjectFile::getWasmRelocation(DataRefImpl Ref) const {
assert(Ref.d.a < Sections.size());
const WasmSection &Sec = Sections[Ref.d.a];
assert(Ref.d.b < Sec.Relocations.size());
return Sec.Relocations[Ref.d.b];
}
int WasmSectionOrderChecker::getSectionOrder(unsigned ID,
StringRef CustomSectionName) {
switch (ID) {
case wasm::WASM_SEC_CUSTOM:
return StringSwitch<unsigned>(CustomSectionName)
.Case("dylink", WASM_SEC_ORDER_DYLINK)
.Case("dylink.0", WASM_SEC_ORDER_DYLINK)
.Case("linking", WASM_SEC_ORDER_LINKING)
.StartsWith("reloc.", WASM_SEC_ORDER_RELOC)
.Case("name", WASM_SEC_ORDER_NAME)
.Case("producers", WASM_SEC_ORDER_PRODUCERS)
.Case("target_features", WASM_SEC_ORDER_TARGET_FEATURES)
.Default(WASM_SEC_ORDER_NONE);
case wasm::WASM_SEC_TYPE:
return WASM_SEC_ORDER_TYPE;
case wasm::WASM_SEC_IMPORT:
return WASM_SEC_ORDER_IMPORT;
case wasm::WASM_SEC_FUNCTION:
return WASM_SEC_ORDER_FUNCTION;
case wasm::WASM_SEC_TABLE:
return WASM_SEC_ORDER_TABLE;
case wasm::WASM_SEC_MEMORY:
return WASM_SEC_ORDER_MEMORY;
case wasm::WASM_SEC_GLOBAL:
return WASM_SEC_ORDER_GLOBAL;
case wasm::WASM_SEC_EXPORT:
return WASM_SEC_ORDER_EXPORT;
case wasm::WASM_SEC_START:
return WASM_SEC_ORDER_START;
case wasm::WASM_SEC_ELEM:
return WASM_SEC_ORDER_ELEM;
case wasm::WASM_SEC_CODE:
return WASM_SEC_ORDER_CODE;
case wasm::WASM_SEC_DATA:
return WASM_SEC_ORDER_DATA;
case wasm::WASM_SEC_DATACOUNT:
return WASM_SEC_ORDER_DATACOUNT;
case wasm::WASM_SEC_TAG:
return WASM_SEC_ORDER_TAG;
default:
return WASM_SEC_ORDER_NONE;
}
}
// Represents the edges in a directed graph where any node B reachable from node
// A is not allowed to appear before A in the section ordering, but may appear
// afterward.
int WasmSectionOrderChecker::DisallowedPredecessors
[WASM_NUM_SEC_ORDERS][WASM_NUM_SEC_ORDERS] = {
// WASM_SEC_ORDER_NONE
{},
// WASM_SEC_ORDER_TYPE
{WASM_SEC_ORDER_TYPE, WASM_SEC_ORDER_IMPORT},
// WASM_SEC_ORDER_IMPORT
{WASM_SEC_ORDER_IMPORT, WASM_SEC_ORDER_FUNCTION},
// WASM_SEC_ORDER_FUNCTION
{WASM_SEC_ORDER_FUNCTION, WASM_SEC_ORDER_TABLE},
// WASM_SEC_ORDER_TABLE
{WASM_SEC_ORDER_TABLE, WASM_SEC_ORDER_MEMORY},
// WASM_SEC_ORDER_MEMORY
{WASM_SEC_ORDER_MEMORY, WASM_SEC_ORDER_TAG},
// WASM_SEC_ORDER_TAG
{WASM_SEC_ORDER_TAG, WASM_SEC_ORDER_GLOBAL},
// WASM_SEC_ORDER_GLOBAL
{WASM_SEC_ORDER_GLOBAL, WASM_SEC_ORDER_EXPORT},
// WASM_SEC_ORDER_EXPORT
{WASM_SEC_ORDER_EXPORT, WASM_SEC_ORDER_START},
// WASM_SEC_ORDER_START
{WASM_SEC_ORDER_START, WASM_SEC_ORDER_ELEM},
// WASM_SEC_ORDER_ELEM
{WASM_SEC_ORDER_ELEM, WASM_SEC_ORDER_DATACOUNT},
// WASM_SEC_ORDER_DATACOUNT
{WASM_SEC_ORDER_DATACOUNT, WASM_SEC_ORDER_CODE},
// WASM_SEC_ORDER_CODE
{WASM_SEC_ORDER_CODE, WASM_SEC_ORDER_DATA},
// WASM_SEC_ORDER_DATA
{WASM_SEC_ORDER_DATA, WASM_SEC_ORDER_LINKING},
// Custom Sections
// WASM_SEC_ORDER_DYLINK
{WASM_SEC_ORDER_DYLINK, WASM_SEC_ORDER_TYPE},
// WASM_SEC_ORDER_LINKING
{WASM_SEC_ORDER_LINKING, WASM_SEC_ORDER_RELOC, WASM_SEC_ORDER_NAME},
// WASM_SEC_ORDER_RELOC (can be repeated)
{},
// WASM_SEC_ORDER_NAME
{WASM_SEC_ORDER_NAME, WASM_SEC_ORDER_PRODUCERS},
// WASM_SEC_ORDER_PRODUCERS
{WASM_SEC_ORDER_PRODUCERS, WASM_SEC_ORDER_TARGET_FEATURES},
// WASM_SEC_ORDER_TARGET_FEATURES
{WASM_SEC_ORDER_TARGET_FEATURES}};
bool WasmSectionOrderChecker::isValidSectionOrder(unsigned ID,
StringRef CustomSectionName) {
int Order = getSectionOrder(ID, CustomSectionName);
if (Order == WASM_SEC_ORDER_NONE)
return true;
// Disallowed predecessors we need to check for
SmallVector<int, WASM_NUM_SEC_ORDERS> WorkList;
// Keep track of completed checks to avoid repeating work
bool Checked[WASM_NUM_SEC_ORDERS] = {};
int Curr = Order;
while (true) {
// Add new disallowed predecessors to work list
for (size_t I = 0;; ++I) {
int Next = DisallowedPredecessors[Curr][I];
if (Next == WASM_SEC_ORDER_NONE)
break;
if (Checked[Next])
continue;
WorkList.push_back(Next);
Checked[Next] = true;
}
if (WorkList.empty())
break;
// Consider next disallowed predecessor
Curr = WorkList.pop_back_val();
if (Seen[Curr])
return false;
}
// Have not seen any disallowed predecessors
Seen[Order] = true;
return true;
}