llvm-project/llvm/lib/Object/WasmObjectFile.cpp

1204 lines
40 KiB
C++

//===- WasmObjectFile.cpp - Wasm object file implementation ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/ADT/Triple.h"
#include "llvm/BinaryFormat/Wasm.h"
#include "llvm/MC/SubtargetFeature.h"
#include "llvm/Object/Binary.h"
#include "llvm/Object/Error.h"
#include "llvm/Object/ObjectFile.h"
#include "llvm/Object/SymbolicFile.h"
#include "llvm/Object/Wasm.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/LEB128.h"
#include <algorithm>
#include <cassert>
#include <cstdint>
#include <cstring>
#include <system_error>
#define DEBUG_TYPE "wasm-object"
using namespace llvm;
using namespace object;
Expected<std::unique_ptr<WasmObjectFile>>
ObjectFile::createWasmObjectFile(MemoryBufferRef Buffer) {
Error Err = Error::success();
auto ObjectFile = llvm::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(const uint8_t *&Ptr) { return *Ptr++; }
static uint32_t readUint32(const uint8_t *&Ptr) {
uint32_t Result = support::endian::read32le(Ptr);
Ptr += sizeof(Result);
return Result;
}
static int32_t readFloat32(const uint8_t *&Ptr) {
int32_t Result = 0;
memcpy(&Result, Ptr, sizeof(Result));
Ptr += sizeof(Result);
return Result;
}
static int64_t readFloat64(const uint8_t *&Ptr) {
int64_t Result = 0;
memcpy(&Result, Ptr, sizeof(Result));
Ptr += sizeof(Result);
return Result;
}
static uint64_t readULEB128(const uint8_t *&Ptr) {
unsigned Count;
uint64_t Result = decodeULEB128(Ptr, &Count);
Ptr += Count;
return Result;
}
static StringRef readString(const uint8_t *&Ptr) {
uint32_t StringLen = readULEB128(Ptr);
StringRef Return = StringRef(reinterpret_cast<const char *>(Ptr), StringLen);
Ptr += StringLen;
return Return;
}
static int64_t readLEB128(const uint8_t *&Ptr) {
unsigned Count;
uint64_t Result = decodeSLEB128(Ptr, &Count);
Ptr += Count;
return Result;
}
static uint8_t readVaruint1(const uint8_t *&Ptr) {
int64_t result = readLEB128(Ptr);
assert(result <= VARUINT1_MAX && result >= 0);
return result;
}
static int8_t readVarint7(const uint8_t *&Ptr) {
int64_t result = readLEB128(Ptr);
assert(result <= VARINT7_MAX && result >= VARINT7_MIN);
return result;
}
static uint8_t readVaruint7(const uint8_t *&Ptr) {
uint64_t result = readULEB128(Ptr);
assert(result <= VARUINT7_MAX);
return result;
}
static int32_t readVarint32(const uint8_t *&Ptr) {
int64_t result = readLEB128(Ptr);
assert(result <= INT32_MAX && result >= INT32_MIN);
return result;
}
static uint32_t readVaruint32(const uint8_t *&Ptr) {
uint64_t result = readULEB128(Ptr);
assert(result <= UINT32_MAX);
return result;
}
static int64_t readVarint64(const uint8_t *&Ptr) {
return readLEB128(Ptr);
}
static uint8_t readOpcode(const uint8_t *&Ptr) {
return readUint8(Ptr);
}
static Error readInitExpr(wasm::WasmInitExpr &Expr, const uint8_t *&Ptr) {
Expr.Opcode = readOpcode(Ptr);
switch (Expr.Opcode) {
case wasm::WASM_OPCODE_I32_CONST:
Expr.Value.Int32 = readVarint32(Ptr);
break;
case wasm::WASM_OPCODE_I64_CONST:
Expr.Value.Int64 = readVarint64(Ptr);
break;
case wasm::WASM_OPCODE_F32_CONST:
Expr.Value.Float32 = readFloat32(Ptr);
break;
case wasm::WASM_OPCODE_F64_CONST:
Expr.Value.Float64 = readFloat64(Ptr);
break;
case wasm::WASM_OPCODE_GET_GLOBAL:
Expr.Value.Global = readULEB128(Ptr);
break;
default:
return make_error<GenericBinaryError>("Invalid opcode in init_expr",
object_error::parse_failed);
}
uint8_t EndOpcode = readOpcode(Ptr);
if (EndOpcode != wasm::WASM_OPCODE_END) {
return make_error<GenericBinaryError>("Invalid init_expr",
object_error::parse_failed);
}
return Error::success();
}
static wasm::WasmLimits readLimits(const uint8_t *&Ptr) {
wasm::WasmLimits Result;
Result.Flags = readVaruint1(Ptr);
Result.Initial = readVaruint32(Ptr);
if (Result.Flags & wasm::WASM_LIMITS_FLAG_HAS_MAX)
Result.Maximum = readVaruint32(Ptr);
return Result;
}
static wasm::WasmTable readTable(const uint8_t *&Ptr) {
wasm::WasmTable Table;
Table.ElemType = readVarint7(Ptr);
Table.Limits = readLimits(Ptr);
return Table;
}
static Error readSection(WasmSection &Section, const uint8_t *&Ptr,
const uint8_t *Start, const uint8_t *Eof) {
Section.Offset = Ptr - Start;
Section.Type = readVaruint7(Ptr);
uint32_t Size = readVaruint32(Ptr);
if (Size == 0)
return make_error<StringError>("Zero length section",
object_error::parse_failed);
if (Ptr + Size > Eof)
return make_error<StringError>("Section too large",
object_error::parse_failed);
Section.Content = ArrayRef<uint8_t>(Ptr, Size);
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>("Bad magic number",
object_error::parse_failed);
return;
}
const uint8_t *Eof = getPtr(getData().size());
const uint8_t *Ptr = getPtr(4);
if (Ptr + 4 > Eof) {
Err = make_error<StringError>("Missing version number",
object_error::parse_failed);
return;
}
Header.Version = readUint32(Ptr);
if (Header.Version != wasm::WasmVersion) {
Err = make_error<StringError>("Bad version number",
object_error::parse_failed);
return;
}
WasmSection Sec;
while (Ptr < Eof) {
if ((Err = readSection(Sec, Ptr, getPtr(0), Eof)))
return;
if ((Err = parseSection(Sec)))
return;
Sections.push_back(Sec);
}
}
Error WasmObjectFile::parseSection(WasmSection &Sec) {
const uint8_t* Start = Sec.Content.data();
const uint8_t* End = Start + Sec.Content.size();
switch (Sec.Type) {
case wasm::WASM_SEC_CUSTOM:
return parseCustomSection(Sec, Start, End);
case wasm::WASM_SEC_TYPE:
return parseTypeSection(Start, End);
case wasm::WASM_SEC_IMPORT:
return parseImportSection(Start, End);
case wasm::WASM_SEC_FUNCTION:
return parseFunctionSection(Start, End);
case wasm::WASM_SEC_TABLE:
return parseTableSection(Start, End);
case wasm::WASM_SEC_MEMORY:
return parseMemorySection(Start, End);
case wasm::WASM_SEC_GLOBAL:
return parseGlobalSection(Start, End);
case wasm::WASM_SEC_EXPORT:
return parseExportSection(Start, End);
case wasm::WASM_SEC_START:
return parseStartSection(Start, End);
case wasm::WASM_SEC_ELEM:
return parseElemSection(Start, End);
case wasm::WASM_SEC_CODE:
return parseCodeSection(Start, End);
case wasm::WASM_SEC_DATA:
return parseDataSection(Start, End);
default:
return make_error<GenericBinaryError>("Bad section type",
object_error::parse_failed);
}
}
Error WasmObjectFile::parseNameSection(const uint8_t *Ptr, const uint8_t *End) {
llvm::DenseSet<uint64_t> Seen;
if (Functions.size() != FunctionTypes.size()) {
return make_error<GenericBinaryError>("Names must come after code section",
object_error::parse_failed);
}
while (Ptr < End) {
uint8_t Type = readVarint7(Ptr);
uint32_t Size = readVaruint32(Ptr);
const uint8_t *SubSectionEnd = Ptr + Size;
switch (Type) {
case wasm::WASM_NAMES_FUNCTION: {
uint32_t Count = readVaruint32(Ptr);
while (Count--) {
uint32_t Index = readVaruint32(Ptr);
if (!Seen.insert(Index).second)
return make_error<GenericBinaryError>("Function named more than once",
object_error::parse_failed);
StringRef Name = readString(Ptr);
if (!isValidFunctionIndex(Index) || Name.empty())
return make_error<GenericBinaryError>("Invalid name entry",
object_error::parse_failed);
DebugNames.push_back(wasm::WasmFunctionName{Index, Name});
if (isDefinedFunctionIndex(Index)) {
// Override any existing name; the name specified by the "names"
// section is the Function's canonical name.
getDefinedFunction(Index).Name = Name;
}
}
break;
}
// Ignore local names for now
case wasm::WASM_NAMES_LOCAL:
default:
Ptr += Size;
break;
}
if (Ptr != SubSectionEnd)
return make_error<GenericBinaryError>("Name sub-section ended prematurely",
object_error::parse_failed);
}
if (Ptr != End)
return make_error<GenericBinaryError>("Name section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseLinkingSection(const uint8_t *Ptr,
const uint8_t *End) {
HasLinkingSection = true;
if (Functions.size() != FunctionTypes.size()) {
return make_error<GenericBinaryError>(
"Linking data must come after code section", object_error::parse_failed);
}
while (Ptr < End) {
uint8_t Type = readVarint7(Ptr);
uint32_t Size = readVaruint32(Ptr);
const uint8_t *SubSectionEnd = Ptr + Size;
switch (Type) {
case wasm::WASM_SYMBOL_TABLE:
if (Error Err = parseLinkingSectionSymtab(Ptr, SubSectionEnd))
return Err;
break;
case wasm::WASM_SEGMENT_INFO: {
uint32_t Count = readVaruint32(Ptr);
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(Ptr);
DataSegments[i].Data.Alignment = readVaruint32(Ptr);
DataSegments[i].Data.Flags = readVaruint32(Ptr);
}
break;
}
case wasm::WASM_INIT_FUNCS: {
uint32_t Count = readVaruint32(Ptr);
LinkingData.InitFunctions.reserve(Count);
for (uint32_t i = 0; i < Count; i++) {
wasm::WasmInitFunc Init;
Init.Priority = readVaruint32(Ptr);
Init.Symbol = readVaruint32(Ptr);
if (!isValidFunctionSymbolIndex(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(Ptr, SubSectionEnd))
return Err;
break;
default:
Ptr += Size;
break;
}
if (Ptr != SubSectionEnd)
return make_error<GenericBinaryError>(
"Linking sub-section ended prematurely", object_error::parse_failed);
}
if (Ptr != End)
return make_error<GenericBinaryError>("Linking section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseLinkingSectionSymtab(const uint8_t *&Ptr,
const uint8_t *End) {
uint32_t Count = readVaruint32(Ptr);
LinkingData.SymbolTable.reserve(Count);
Symbols.reserve(Count);
StringSet<> SymbolNames;
std::vector<wasm::WasmImport *> ImportedGlobals;
std::vector<wasm::WasmImport *> ImportedFunctions;
ImportedGlobals.reserve(Imports.size());
ImportedFunctions.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);
}
while (Count--) {
wasm::WasmSymbolInfo Info;
const wasm::WasmSignature *FunctionType = nullptr;
const wasm::WasmGlobalType *GlobalType = nullptr;
Info.Kind = readUint8(Ptr);
Info.Flags = readVaruint32(Ptr);
bool IsDefined = (Info.Flags & wasm::WASM_SYMBOL_UNDEFINED) == 0;
switch (Info.Kind) {
case wasm::WASM_SYMBOL_TYPE_FUNCTION:
Info.ElementIndex = readVaruint32(Ptr);
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(Ptr);
unsigned FuncIndex = Info.ElementIndex - NumImportedFunctions;
FunctionType = &Signatures[FunctionTypes[FuncIndex]];
auto &Function = Functions[FuncIndex];
if (Function.Name.empty()) {
// Use the symbol's name to set a name for the Function, but only if
// one hasn't already been set.
Function.Name = Info.Name;
}
} else {
wasm::WasmImport &Import = *ImportedFunctions[Info.ElementIndex];
FunctionType = &Signatures[Import.SigIndex];
Info.Name = Import.Field;
}
break;
case wasm::WASM_SYMBOL_TYPE_GLOBAL:
Info.ElementIndex = readVaruint32(Ptr);
if (!isValidGlobalIndex(Info.ElementIndex) ||
IsDefined != isDefinedGlobalIndex(Info.ElementIndex))
return make_error<GenericBinaryError>("invalid global symbol index",
object_error::parse_failed);
if (IsDefined) {
Info.Name = readString(Ptr);
unsigned GlobalIndex = Info.ElementIndex - NumImportedGlobals;
GlobalType = &Globals[GlobalIndex].Type;
} else {
wasm::WasmImport &Import = *ImportedGlobals[Info.ElementIndex];
Info.Name = Import.Field;
GlobalType = &Import.Global;
}
break;
case wasm::WASM_SYMBOL_TYPE_DATA:
Info.Name = readString(Ptr);
if (IsDefined) {
uint32_t Index = readVaruint32(Ptr);
if (Index >= DataSegments.size())
return make_error<GenericBinaryError>("invalid data symbol index",
object_error::parse_failed);
uint32_t Offset = readVaruint32(Ptr);
uint32_t Size = readVaruint32(Ptr);
if (Offset + Size > DataSegments[Index].Data.Content.size())
return make_error<GenericBinaryError>("invalid data symbol offset",
object_error::parse_failed);
Info.DataRef = wasm::WasmDataReference{Index, Offset, Size};
}
break;
default:
return make_error<GenericBinaryError>("Invalid symbol type",
object_error::parse_failed);
}
if ((Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) !=
wasm::WASM_SYMBOL_BINDING_LOCAL &&
!SymbolNames.insert(Info.Name).second)
return make_error<GenericBinaryError>("Duplicate symbol name " +
Twine(Info.Name),
object_error::parse_failed);
LinkingData.SymbolTable.emplace_back(Info);
Symbols.emplace_back(LinkingData.SymbolTable.back(), FunctionType,
GlobalType);
DEBUG(dbgs() << "Adding symbol: " << Symbols.back() << "\n");
}
return Error::success();
}
Error WasmObjectFile::parseLinkingSectionComdat(const uint8_t *&Ptr,
const uint8_t *End)
{
uint32_t ComdatCount = readVaruint32(Ptr);
StringSet<> ComdatSet;
while (ComdatCount--) {
StringRef Name = readString(Ptr);
if (Name.empty() || !ComdatSet.insert(Name).second)
return make_error<GenericBinaryError>("Bad/duplicate COMDAT name " + Twine(Name),
object_error::parse_failed);
Comdats.emplace_back(Name);
uint32_t Flags = readVaruint32(Ptr);
if (Flags != 0)
return make_error<GenericBinaryError>("Unsupported COMDAT flags",
object_error::parse_failed);
uint32_t EntryCount = readVaruint32(Ptr);
while (EntryCount--) {
unsigned Kind = readVaruint32(Ptr);
unsigned Index = readVaruint32(Ptr);
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.empty())
return make_error<GenericBinaryError>("Data segment in two COMDATs",
object_error::parse_failed);
DataSegments[Index].Data.Comdat = Name;
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.empty())
return make_error<GenericBinaryError>("Function in two COMDATs",
object_error::parse_failed);
getDefinedFunction(Index).Comdat = Name;
break;
}
}
}
return Error::success();
}
WasmSection* WasmObjectFile::findCustomSectionByName(StringRef Name) {
for (WasmSection& Section : Sections) {
if (Section.Type == wasm::WASM_SEC_CUSTOM && Section.Name == Name)
return &Section;
}
return nullptr;
}
WasmSection* WasmObjectFile::findSectionByType(uint32_t Type) {
assert(Type != wasm::WASM_SEC_CUSTOM);
for (WasmSection& Section : Sections) {
if (Section.Type == Type)
return &Section;
}
return nullptr;
}
Error WasmObjectFile::parseRelocSection(StringRef Name, const uint8_t *Ptr,
const uint8_t *End) {
uint8_t SectionCode = readVarint7(Ptr);
WasmSection* Section = nullptr;
if (SectionCode == wasm::WASM_SEC_CUSTOM) {
StringRef Name = readString(Ptr);
Section = findCustomSectionByName(Name);
} else {
Section = findSectionByType(SectionCode);
}
if (!Section)
return make_error<GenericBinaryError>("Invalid section code",
object_error::parse_failed);
uint32_t RelocCount = readVaruint32(Ptr);
while (RelocCount--) {
wasm::WasmRelocation Reloc;
memset(&Reloc, 0, sizeof(Reloc));
Reloc.Type = readVaruint32(Ptr);
Reloc.Offset = readVaruint32(Ptr);
Reloc.Index = readVaruint32(Ptr);
switch (Reloc.Type) {
case wasm::R_WEBASSEMBLY_FUNCTION_INDEX_LEB:
case wasm::R_WEBASSEMBLY_TABLE_INDEX_SLEB:
case wasm::R_WEBASSEMBLY_TABLE_INDEX_I32:
case wasm::R_WEBASSEMBLY_TYPE_INDEX_LEB:
case wasm::R_WEBASSEMBLY_GLOBAL_INDEX_LEB:
break;
case wasm::R_WEBASSEMBLY_MEMORY_ADDR_LEB:
case wasm::R_WEBASSEMBLY_MEMORY_ADDR_SLEB:
case wasm::R_WEBASSEMBLY_MEMORY_ADDR_I32:
Reloc.Addend = readVarint32(Ptr);
break;
default:
return make_error<GenericBinaryError>("Bad relocation type: " +
Twine(Reloc.Type),
object_error::parse_failed);
}
Section->Relocations.push_back(Reloc);
}
if (Ptr != End)
return make_error<GenericBinaryError>("Reloc section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseCustomSection(WasmSection &Sec,
const uint8_t *Ptr, const uint8_t *End) {
Sec.Name = readString(Ptr);
if (Sec.Name == "name") {
if (Error Err = parseNameSection(Ptr, End))
return Err;
} else if (Sec.Name == "linking") {
if (Error Err = parseLinkingSection(Ptr, End))
return Err;
} else if (Sec.Name.startswith("reloc.")) {
if (Error Err = parseRelocSection(Sec.Name, Ptr, End))
return Err;
}
return Error::success();
}
Error WasmObjectFile::parseTypeSection(const uint8_t *Ptr, const uint8_t *End) {
uint32_t Count = readVaruint32(Ptr);
Signatures.reserve(Count);
while (Count--) {
wasm::WasmSignature Sig;
Sig.ReturnType = wasm::WASM_TYPE_NORESULT;
int8_t Form = readVarint7(Ptr);
if (Form != wasm::WASM_TYPE_FUNC) {
return make_error<GenericBinaryError>("Invalid signature type",
object_error::parse_failed);
}
uint32_t ParamCount = readVaruint32(Ptr);
Sig.ParamTypes.reserve(ParamCount);
while (ParamCount--) {
uint32_t ParamType = readVarint7(Ptr);
Sig.ParamTypes.push_back(ParamType);
}
uint32_t ReturnCount = readVaruint32(Ptr);
if (ReturnCount) {
if (ReturnCount != 1) {
return make_error<GenericBinaryError>(
"Multiple return types not supported", object_error::parse_failed);
}
Sig.ReturnType = readVarint7(Ptr);
}
Signatures.push_back(Sig);
}
if (Ptr != End)
return make_error<GenericBinaryError>("Type section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseImportSection(const uint8_t *Ptr, const uint8_t *End) {
uint32_t Count = readVaruint32(Ptr);
Imports.reserve(Count);
for (uint32_t i = 0; i < Count; i++) {
wasm::WasmImport Im;
Im.Module = readString(Ptr);
Im.Field = readString(Ptr);
Im.Kind = readUint8(Ptr);
switch (Im.Kind) {
case wasm::WASM_EXTERNAL_FUNCTION:
NumImportedFunctions++;
Im.SigIndex = readVaruint32(Ptr);
break;
case wasm::WASM_EXTERNAL_GLOBAL:
NumImportedGlobals++;
Im.Global.Type = readVarint7(Ptr);
Im.Global.Mutable = readVaruint1(Ptr);
break;
case wasm::WASM_EXTERNAL_MEMORY:
Im.Memory = readLimits(Ptr);
break;
case wasm::WASM_EXTERNAL_TABLE:
Im.Table = readTable(Ptr);
if (Im.Table.ElemType != wasm::WASM_TYPE_ANYFUNC)
return make_error<GenericBinaryError>("Invalid table element type",
object_error::parse_failed);
break;
default:
return make_error<GenericBinaryError>(
"Unexpected import kind", object_error::parse_failed);
}
Imports.push_back(Im);
}
if (Ptr != End)
return make_error<GenericBinaryError>("Import section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseFunctionSection(const uint8_t *Ptr, const uint8_t *End) {
uint32_t Count = readVaruint32(Ptr);
FunctionTypes.reserve(Count);
while (Count--) {
FunctionTypes.push_back(readVaruint32(Ptr));
}
if (Ptr != End)
return make_error<GenericBinaryError>("Function section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseTableSection(const uint8_t *Ptr, const uint8_t *End) {
uint32_t Count = readVaruint32(Ptr);
Tables.reserve(Count);
while (Count--) {
Tables.push_back(readTable(Ptr));
if (Tables.back().ElemType != wasm::WASM_TYPE_ANYFUNC) {
return make_error<GenericBinaryError>("Invalid table element type",
object_error::parse_failed);
}
}
if (Ptr != End)
return make_error<GenericBinaryError>("Table section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseMemorySection(const uint8_t *Ptr, const uint8_t *End) {
uint32_t Count = readVaruint32(Ptr);
Memories.reserve(Count);
while (Count--) {
Memories.push_back(readLimits(Ptr));
}
if (Ptr != End)
return make_error<GenericBinaryError>("Memory section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseGlobalSection(const uint8_t *Ptr, const uint8_t *End) {
GlobalSection = Sections.size();
uint32_t Count = readVaruint32(Ptr);
Globals.reserve(Count);
while (Count--) {
wasm::WasmGlobal Global;
Global.Index = NumImportedGlobals + Globals.size();
Global.Type.Type = readVarint7(Ptr);
Global.Type.Mutable = readVaruint1(Ptr);
if (Error Err = readInitExpr(Global.InitExpr, Ptr))
return Err;
Globals.push_back(Global);
}
if (Ptr != End)
return make_error<GenericBinaryError>("Global section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseExportSection(const uint8_t *Ptr, const uint8_t *End) {
uint32_t Count = readVaruint32(Ptr);
Exports.reserve(Count);
for (uint32_t i = 0; i < Count; i++) {
wasm::WasmExport Ex;
Ex.Name = readString(Ptr);
Ex.Kind = readUint8(Ptr);
Ex.Index = readVaruint32(Ptr);
switch (Ex.Kind) {
case wasm::WASM_EXTERNAL_FUNCTION:
if (!isValidFunctionIndex(Ex.Index))
return make_error<GenericBinaryError>("Invalid function export",
object_error::parse_failed);
break;
case wasm::WASM_EXTERNAL_GLOBAL:
if (!isValidGlobalIndex(Ex.Index))
return make_error<GenericBinaryError>("Invalid global export",
object_error::parse_failed);
break;
case wasm::WASM_EXTERNAL_MEMORY:
case wasm::WASM_EXTERNAL_TABLE:
break;
default:
return make_error<GenericBinaryError>(
"Unexpected export kind", object_error::parse_failed);
}
Exports.push_back(Ex);
}
if (Ptr != 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 + FunctionTypes.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::isDefinedGlobalIndex(uint32_t Index) const {
return Index >= NumImportedGlobals && isValidGlobalIndex(Index);
}
bool WasmObjectFile::isValidFunctionSymbolIndex(uint32_t Index) const {
return Index < Symbols.size() && Symbols[Index].isTypeFunction();
}
wasm::WasmFunction &WasmObjectFile::getDefinedFunction(uint32_t Index) {
assert(isDefinedFunctionIndex(Index));
return Functions[Index - NumImportedFunctions];
}
wasm::WasmGlobal &WasmObjectFile::getDefinedGlobal(uint32_t Index) {
assert(isDefinedGlobalIndex(Index));
return Globals[Index - NumImportedGlobals];
}
Error WasmObjectFile::parseStartSection(const uint8_t *Ptr, const uint8_t *End) {
StartFunction = readVaruint32(Ptr);
if (!isValidFunctionIndex(StartFunction))
return make_error<GenericBinaryError>("Invalid start function",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseCodeSection(const uint8_t *Ptr, const uint8_t *End) {
CodeSection = Sections.size();
const uint8_t *CodeSectionStart = Ptr;
uint32_t FunctionCount = readVaruint32(Ptr);
if (FunctionCount != FunctionTypes.size()) {
return make_error<GenericBinaryError>("Invalid function count",
object_error::parse_failed);
}
while (FunctionCount--) {
wasm::WasmFunction Function;
const uint8_t *FunctionStart = Ptr;
uint32_t Size = readVaruint32(Ptr);
const uint8_t *FunctionEnd = Ptr + Size;
Function.Index = NumImportedFunctions + Functions.size();
Function.CodeSectionOffset = FunctionStart - CodeSectionStart;
Function.Size = FunctionEnd - FunctionStart;
uint32_t NumLocalDecls = readVaruint32(Ptr);
Function.Locals.reserve(NumLocalDecls);
while (NumLocalDecls--) {
wasm::WasmLocalDecl Decl;
Decl.Count = readVaruint32(Ptr);
Decl.Type = readVarint7(Ptr);
Function.Locals.push_back(Decl);
}
uint32_t BodySize = FunctionEnd - Ptr;
Function.Body = ArrayRef<uint8_t>(Ptr, BodySize);
Ptr += BodySize;
assert(Ptr == FunctionEnd);
Functions.push_back(Function);
}
if (Ptr != End)
return make_error<GenericBinaryError>("Code section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseElemSection(const uint8_t *Ptr, const uint8_t *End) {
uint32_t Count = readVaruint32(Ptr);
ElemSegments.reserve(Count);
while (Count--) {
wasm::WasmElemSegment Segment;
Segment.TableIndex = readVaruint32(Ptr);
if (Segment.TableIndex != 0) {
return make_error<GenericBinaryError>("Invalid TableIndex",
object_error::parse_failed);
}
if (Error Err = readInitExpr(Segment.Offset, Ptr))
return Err;
uint32_t NumElems = readVaruint32(Ptr);
while (NumElems--) {
Segment.Functions.push_back(readVaruint32(Ptr));
}
ElemSegments.push_back(Segment);
}
if (Ptr != End)
return make_error<GenericBinaryError>("Elem section ended prematurely",
object_error::parse_failed);
return Error::success();
}
Error WasmObjectFile::parseDataSection(const uint8_t *Ptr, const uint8_t *End) {
DataSection = Sections.size();
const uint8_t *Start = Ptr;
uint32_t Count = readVaruint32(Ptr);
DataSegments.reserve(Count);
while (Count--) {
WasmSegment Segment;
Segment.Data.MemoryIndex = readVaruint32(Ptr);
if (Error Err = readInitExpr(Segment.Data.Offset, Ptr))
return Err;
uint32_t Size = readVaruint32(Ptr);
Segment.Data.Content = ArrayRef<uint8_t>(Ptr, Size);
Segment.Data.Alignment = 0;
Segment.Data.Flags = 0;
Segment.SectionOffset = Ptr - Start;
Ptr += Size;
DataSegments.push_back(Segment);
}
if (Ptr != End)
return make_error<GenericBinaryError>("Data section ended prematurely",
object_error::parse_failed);
return Error::success();
}
const uint8_t *WasmObjectFile::getPtr(size_t Offset) const {
return reinterpret_cast<const uint8_t *>(getData().substr(Offset, 1).data());
}
const wasm::WasmObjectHeader &WasmObjectFile::getHeader() const {
return Header;
}
void WasmObjectFile::moveSymbolNext(DataRefImpl &Symb) const { Symb.d.a++; }
uint32_t WasmObjectFile::getSymbolFlags(DataRefImpl Symb) const {
uint32_t Result = SymbolRef::SF_None;
const WasmSymbol &Sym = getWasmSymbol(Symb);
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 = 0;
return BasicSymbolRef(Ref, this);
}
basic_symbol_iterator WasmObjectFile::symbol_end() const {
DataRefImpl Ref;
Ref.d.a = Symbols.size();
return BasicSymbolRef(Ref, this);
}
const WasmSymbol &WasmObjectFile::getWasmSymbol(const DataRefImpl &Symb) const {
return Symbols[Symb.d.a];
}
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 {
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:
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;
assert(Segment.Offset.Opcode == wasm::WASM_OPCODE_I32_CONST);
return Segment.Offset.Value.Int32 + Sym.Info.DataRef.Offset;
}
}
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;
}
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;
switch (Sym.Info.Kind) {
case wasm::WASM_SYMBOL_TYPE_FUNCTION:
Ref.d.a = CodeSection;
break;
case wasm::WASM_SYMBOL_TYPE_GLOBAL:
Ref.d.a = GlobalSection;
break;
case wasm::WASM_SYMBOL_TYPE_DATA:
Ref.d.a = DataSection;
break;
default:
llvm_unreachable("Unknown WasmSymbol::SymbolType");
}
return section_iterator(SectionRef(Ref, this));
}
void WasmObjectFile::moveSectionNext(DataRefImpl &Sec) const { Sec.d.a++; }
std::error_code WasmObjectFile::getSectionName(DataRefImpl Sec,
StringRef &Res) const {
const WasmSection &S = Sections[Sec.d.a];
#define ECase(X) \
case wasm::WASM_SEC_##X: \
Res = #X; \
break
switch (S.Type) {
ECase(TYPE);
ECase(IMPORT);
ECase(FUNCTION);
ECase(TABLE);
ECase(MEMORY);
ECase(GLOBAL);
ECase(EXPORT);
ECase(START);
ECase(ELEM);
ECase(CODE);
ECase(DATA);
case wasm::WASM_SEC_CUSTOM:
Res = S.Name;
break;
default:
return object_error::invalid_section_index;
}
#undef ECase
return std::error_code();
}
uint64_t WasmObjectFile::getSectionAddress(DataRefImpl Sec) const { return 0; }
uint64_t WasmObjectFile::getSectionIndex(DataRefImpl Sec) const {
return Sec.d.a;
}
uint64_t WasmObjectFile::getSectionSize(DataRefImpl Sec) const {
const WasmSection &S = Sections[Sec.d.a];
return S.Content.size();
}
std::error_code WasmObjectFile::getSectionContents(DataRefImpl Sec,
StringRef &Res) 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).
Res = StringRef(reinterpret_cast<const char *>(S.Content.data()),
S.Content.size());
return std::error_code();
}
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; }
bool WasmObjectFile::isSectionBitcode(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 Rel) const {
llvm_unreachable("not yet implemented");
SymbolRef Ref;
return symbol_iterator(Ref);
}
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 4; }
StringRef WasmObjectFile::getFileFormatName() const { return "WASM"; }
Triple::ArchType WasmObjectFile::getArch() const { return Triple::wasm32; }
SubtargetFeatures WasmObjectFile::getFeatures() const {
return SubtargetFeatures();
}
bool WasmObjectFile::isRelocatableObject() const {
return HasLinkingSection;
}
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];
}