static bool
DecodeImportSection(JSContext* cx, Decoder& d, ModuleGeneratorData* init, ImportNameVector* imports)
{
if (!d.readCStringIf(ImportSection))
return true;
uint32_t sectionStart;
if (!d.startSection(§ionStart))
return Fail(cx, d, "expected import section byte size");
uint32_t numImports;
if (!d.readVarU32(&numImports))
return Fail(cx, d, "expected number of imports");
if (numImports > MaxImports)
return Fail(cx, d, "too many imports");
for (uint32_t i = 0; i < numImports; i++) {
if (!DecodeImport(cx, d, init, imports))
return false;
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "import section byte size mismatch");
return true;
}
static bool
DecodeExportTable(JSContext* cx, Decoder& d, ModuleGenerator& mg)
{
uint32_t sectionStart;
if (!d.startSection(ExportTableId, §ionStart))
return Fail(cx, d, "failed to start section");
if (sectionStart == Decoder::NotStarted)
return true;
CStringSet dupSet(cx);
if (!dupSet.init())
return false;
uint32_t numExports;
if (!d.readVarU32(&numExports))
return Fail(cx, d, "failed to read number of exports");
if (numExports > MaxExports)
return Fail(cx, d, "too many exports");
for (uint32_t i = 0; i < numExports; i++) {
if (!DecodeFunctionExport(cx, d, mg, &dupSet))
return false;
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "export section byte size mismatch");
return true;
}
static bool
DecodeDeclarationSection(JSContext* cx, Decoder& d, ModuleGeneratorData* init)
{
if (!d.readCStringIf(DeclSection))
return true;
uint32_t sectionStart;
if (!d.startSection(§ionStart))
return Fail(cx, d, "expected decl section byte size");
uint32_t numDecls;
if (!d.readVarU32(&numDecls))
return Fail(cx, d, "expected number of declarations");
if (numDecls > MaxFuncs)
return Fail(cx, d, "too many functions");
if (!init->funcSigs.resize(numDecls))
return false;
for (uint32_t i = 0; i < numDecls; i++) {
if (!DecodeSignatureIndex(cx, d, *init, &init->funcSigs[i]))
return false;
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "decls section byte size mismatch");
return true;
}
static bool
DecodeImportTable(JSContext* cx, Decoder& d, ModuleGeneratorData* init, ImportNameVector* importNames)
{
uint32_t sectionStart;
if (!d.startSection(ImportTableId, §ionStart))
return Fail(cx, d, "failed to start section");
if (sectionStart == Decoder::NotStarted)
return true;
uint32_t numImports;
if (!d.readVarU32(&numImports))
return Fail(cx, d, "failed to read number of imports");
if (numImports > MaxImports)
return Fail(cx, d, "too many imports");
for (uint32_t i = 0; i < numImports; i++) {
if (!DecodeImport(cx, d, init, importNames))
return false;
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "import section byte size mismatch");
return true;
}
static bool
DecodeExportsSection(JSContext* cx, Decoder& d, ModuleGenerator& mg)
{
if (!d.readCStringIf(ExportLabel))
return true;
uint32_t sectionStart;
if (!d.startSection(§ionStart))
return Fail(cx, d, "expected export section byte size");
CStringSet dupSet(cx);
if (!dupSet.init())
return false;
for (uint32_t i = 0; !d.readCStringIf(EndLabel); i++) {
if (i >= MaxExports)
return Fail(cx, d, "too many exports");
if (d.readCStringIf(FuncLabel)) {
if (!DecodeFunctionExport(cx, d, mg, &dupSet))
return false;
} else if (d.readCStringIf(MemoryLabel)) {
if (!DecodeMemoryExport(cx, d, mg, &dupSet))
return false;
} else {
return Fail(cx, d, "unexpected export subsection");
}
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "export section byte size mismatch");
return true;
}
static bool
DecodeImportSection(JSContext* cx, Decoder& d, ModuleGeneratorData* init, ImportNameVector* importNames)
{
if (!d.readCStringIf(ImportLabel))
return true;
uint32_t sectionStart;
if (!d.startSection(§ionStart))
return Fail(cx, d, "expected import section byte size");
for (uint32_t i = 0; !d.readCStringIf(EndLabel); i++) {
if (i >= MaxImports)
return Fail(cx, d, "too many imports");
if (!d.readCStringIf(FuncLabel))
return Fail(cx, d, "expected 'func' import subsection");
if (!DecodeImport(cx, d, init, importNames))
return false;
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "import section byte size mismatch");
return true;
}
static bool
DecodeFunctionBodies(JSContext* cx, Decoder& d, ModuleGenerator& mg)
{
if (!mg.startFuncDefs())
return false;
uint32_t sectionStart;
if (!d.startSection(FunctionBodiesId, §ionStart))
return Fail(cx, d, "failed to start section");
if (sectionStart == Decoder::NotStarted) {
if (mg.numFuncSigs() != 0)
return Fail(cx, d, "expected function bodies");
return mg.finishFuncDefs();
}
uint32_t numFuncBodies;
if (!d.readVarU32(&numFuncBodies))
return Fail(cx, d, "expected function body count");
if (numFuncBodies != mg.numFuncSigs())
return Fail(cx, d, "function body count does not match function signature count");
for (uint32_t funcIndex = 0; funcIndex < numFuncBodies; funcIndex++) {
if (!DecodeFunctionBody(cx, d, mg, funcIndex))
return false;
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "function section byte size mismatch");
return mg.finishFuncDefs();
}
static bool
DecodeTableSection(JSContext* cx, Decoder& d, ModuleGeneratorData* init)
{
if (!d.readCStringIf(TableLabel))
return true;
uint32_t sectionStart;
if (!d.startSection(§ionStart))
return Fail(cx, d, "expected table section byte size");
if (!d.readVarU32(&init->numTableElems))
return Fail(cx, d, "expected number of table elems");
if (init->numTableElems > MaxTableElems)
return Fail(cx, d, "too many table elements");
Uint32Vector elems;
if (!elems.resize(init->numTableElems))
return false;
for (uint32_t i = 0; i < init->numTableElems; i++) {
uint32_t funcIndex;
if (!d.readVarU32(&funcIndex))
return Fail(cx, d, "expected table element");
if (funcIndex >= init->funcSigs.length())
return Fail(cx, d, "table element out of range");
elems[i] = funcIndex;
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "table section byte size mismatch");
// Convert the single (heterogeneous) indirect function table into an
// internal set of asm.js-like homogeneous tables indexed by signature.
// Every element in the heterogeneous table is present in only one
// homogeneous table (as determined by its signature). An element's index in
// the heterogeneous table is the same as its index in its homogeneous table
// and all other homogeneous tables are given an entry that will fault if
// called for at that element's index.
for (uint32_t elemIndex = 0; elemIndex < elems.length(); elemIndex++) {
uint32_t funcIndex = elems[elemIndex];
TableModuleGeneratorData& table = init->sigToTable[init->funcSigIndex(funcIndex)];
if (table.numElems == 0) {
table.numElems = elems.length();
if (!table.elemFuncIndices.appendN(ModuleGenerator::BadIndirectCall, elems.length()))
return false;
}
}
for (uint32_t elemIndex = 0; elemIndex < elems.length(); elemIndex++) {
uint32_t funcIndex = elems[elemIndex];
init->sigToTable[init->funcSigIndex(funcIndex)].elemFuncIndices[elemIndex] = funcIndex;
}
return true;
}
static bool
DecodeSignatureSection(JSContext* cx, Decoder& d, ModuleGeneratorData* init)
{
if (!d.readCStringIf(SigSection))
return true;
uint32_t sectionStart;
if (!d.startSection(§ionStart))
return Fail(cx, d, "expected signature section byte size");
uint32_t numSigs;
if (!d.readVarU32(&numSigs))
return Fail(cx, d, "expected number of signatures");
if (numSigs > MaxSigs)
return Fail(cx, d, "too many signatures");
if (!init->sigs.resize(numSigs))
return false;
for (uint32_t sigIndex = 0; sigIndex < numSigs; sigIndex++) {
uint32_t numArgs;
if (!d.readVarU32(&numArgs))
return Fail(cx, d, "bad number of signature args");
if (numArgs > MaxArgsPerFunc)
return Fail(cx, d, "too many arguments in signature");
ExprType result;
if (!DecodeExprType(cx, d, &result))
return false;
ValTypeVector args;
if (!args.resize(numArgs))
return false;
for (uint32_t i = 0; i < numArgs; i++) {
if (!DecodeValType(cx, d, &args[i]))
return false;
}
init->sigs[sigIndex] = Sig(Move(args), result);
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "decls section byte size mismatch");
return true;
}
static bool
DecodeDataSegments(JSContext* cx, Decoder& d, Handle<ArrayBufferObject*> heap)
{
uint32_t sectionStart;
if (!d.startSection(DataSegmentsId, §ionStart))
return Fail(cx, d, "failed to start section");
if (sectionStart == Decoder::NotStarted)
return true;
if (!heap)
return Fail(cx, d, "data section requires a memory section");
uint32_t numSegments;
if (!d.readVarU32(&numSegments))
return Fail(cx, d, "failed to read number of data segments");
uint8_t* const heapBase = heap->dataPointer();
uint32_t const heapLength = heap->byteLength();
uint32_t prevEnd = 0;
for (uint32_t i = 0; i < numSegments; i++) {
uint32_t dstOffset;
if (!d.readVarU32(&dstOffset))
return Fail(cx, d, "expected segment destination offset");
if (dstOffset < prevEnd)
return Fail(cx, d, "data segments must be disjoint and ordered");
uint32_t numBytes;
if (!d.readVarU32(&numBytes))
return Fail(cx, d, "expected segment size");
if (dstOffset > heapLength || heapLength - dstOffset < numBytes)
return Fail(cx, d, "data segment does not fit in memory");
const uint8_t* src;
if (!d.readBytesRaw(numBytes, &src))
return Fail(cx, d, "data segment shorter than declared");
memcpy(heapBase + dstOffset, src, numBytes);
prevEnd = dstOffset + numBytes;
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "data section byte size mismatch");
return true;
}
static bool
DecodeMemory(JSContext* cx, Decoder& d, ModuleGenerator& mg, MutableHandle<ArrayBufferObject*> heap)
{
uint32_t sectionStart;
if (!d.startSection(MemoryId, §ionStart))
return Fail(cx, d, "failed to start section");
if (sectionStart == Decoder::NotStarted)
return true;
uint32_t initialSizePages;
if (!d.readVarU32(&initialSizePages))
return Fail(cx, d, "expected initial memory size");
CheckedInt<int32_t> initialSize = initialSizePages;
initialSize *= PageSize;
if (!initialSize.isValid())
return Fail(cx, d, "initial memory size too big");
uint32_t maxSizePages;
if (!d.readVarU32(&maxSizePages))
return Fail(cx, d, "expected initial memory size");
CheckedInt<int32_t> maxSize = maxSizePages;
maxSize *= PageSize;
if (!maxSize.isValid())
return Fail(cx, d, "initial memory size too big");
uint8_t exported;
if (!d.readFixedU8(&exported))
return Fail(cx, d, "expected exported byte");
if (exported) {
UniqueChars fieldName = DuplicateString("memory");
if (!fieldName || !mg.addMemoryExport(Move(fieldName)))
return false;
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "memory section byte size mismatch");
bool signalsForOOB = CompileArgs(cx).useSignalHandlersForOOB;
heap.set(ArrayBufferObject::createForWasm(cx, initialSize.value(), signalsForOOB));
if (!heap)
return false;
mg.initHeapUsage(HeapUsage::Unshared);
return true;
}
static bool
DecodeFunc(JSContext* cx, Decoder& d, ModuleGenerator& mg, uint32_t funcIndex)
{
int64_t before = PRMJ_Now();
FunctionGenerator fg;
if (!mg.startFuncDef(d.currentOffset(), &fg))
return false;
if (!d.readCStringIf(FuncSubsection))
return Fail(cx, d, "expected 'func' tag");
uint32_t sectionStart;
if (!d.startSection(§ionStart))
return Fail(cx, d, "expected func section byte size");
const DeclaredSig& sig = mg.funcSig(funcIndex);
for (ValType type : sig.args()) {
if (!fg.addLocal(type))
return false;
}
uint32_t numVars;
if (!d.readVarU32(&numVars))
return Fail(cx, d, "expected number of local vars");
for (uint32_t i = 0; i < numVars; i++) {
ValType type;
if (!DecodeValType(cx, d, &type))
return false;
if (!fg.addLocal(type))
return false;
}
if (!DecodeFuncBody(cx, d, mg, fg, funcIndex))
return false;
if (!d.finishSection(sectionStart))
return Fail(cx, d, "func section byte size mismatch");
int64_t after = PRMJ_Now();
unsigned generateTime = (after - before) / PRMJ_USEC_PER_MSEC;
return mg.finishFuncDef(funcIndex, generateTime, &fg);
}
static bool
DecodeMemorySection(JSContext* cx, Decoder& d, ModuleGenerator& mg,
MutableHandle<ArrayBufferObject*> heap)
{
if (!d.readCStringIf(MemoryLabel))
return true;
uint32_t sectionStart;
if (!d.startSection(§ionStart))
return Fail(cx, d, "expected memory section byte size");
if (!d.readCStringIf(InitialLabel))
return Fail(cx, d, "expected memory section initial field");
uint32_t initialHeapSize;
if (!d.readVarU32(&initialHeapSize))
return Fail(cx, d, "expected initial memory size");
if (initialHeapSize < PageSize || initialHeapSize % PageSize != 0)
return Fail(cx, d, "initial memory size not a multiple of 0x10000");
if (initialHeapSize > INT32_MAX)
return Fail(cx, d, "initial memory size too big");
if (!d.readCStringIf(EndLabel))
return Fail(cx, d, "expected end field of memory section");
if (!d.finishSection(sectionStart))
return Fail(cx, d, "memory section byte size mismatch");
bool signalsForOOB = CompileArgs(cx).useSignalHandlersForOOB;
heap.set(ArrayBufferObject::createForWasm(cx, initialHeapSize, signalsForOOB));
if (!heap)
return false;
mg.initHeapUsage(HeapUsage::Unshared);
return true;
}
static bool
DecodeExportsSection(JSContext* cx, Decoder& d, ModuleGenerator& mg, ExportMap* exportMap)
{
if (!d.readCStringIf(ExportSection))
return true;
uint32_t sectionStart;
if (!d.startSection(§ionStart))
return Fail(cx, d, "expected export section byte size");
uint32_t numExports;
if (!d.readVarU32(&numExports))
return Fail(cx, d, "expected number of exports");
if (numExports > MaxExports)
return Fail(cx, d, "too many exports");
for (uint32_t i = 0; i < numExports; i++) {
if (!DecodeExport(cx, d, mg, exportMap))
return false;
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "export section byte size mismatch");
CStringSet dupSet(cx);
if (!dupSet.init())
return false;
for (const UniqueChars& prevName : exportMap->fieldNames) {
CStringSet::AddPtr p = dupSet.lookupForAdd(prevName.get());
if (p)
return Fail(cx, d, "duplicate export");
if (!dupSet.add(p, prevName.get()))
return false;
}
return true;
}
static bool
DecodeCodeSection(JSContext* cx, Decoder& d, ModuleGenerator& mg)
{
if (!mg.startFuncDefs())
return false;
uint32_t funcIndex = 0;
while (d.readCStringIf(CodeSection)) {
uint32_t sectionStart;
if (!d.startSection(§ionStart))
return Fail(cx, d, "expected code section byte size");
uint32_t numFuncs;
if (!d.readVarU32(&numFuncs))
return Fail(cx, d, "expected number of functions");
if (funcIndex + numFuncs > mg.numFuncSigs())
return Fail(cx, d, "more function definitions than declarations");
for (uint32_t i = 0; i < numFuncs; i++) {
if (!DecodeFunc(cx, d, mg, funcIndex++))
return false;
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "code section byte size mismatch");
}
if (funcIndex != mg.numFuncSigs())
return Fail(cx, d, "fewer function definitions than declarations");
if (!mg.finishFuncDefs())
return false;
return true;
}
bool finishSection(const SectionRange& range, const char* name) {
return d_.finishSection(range, name);
}
static bool
DecodeSignatures(JSContext* cx, Decoder& d, ModuleGeneratorData* init)
{
uint32_t sectionStart;
if (!d.startSection(SignaturesId, §ionStart))
return Fail(cx, d, "failed to start section");
if (sectionStart == Decoder::NotStarted)
return true;
uint32_t numSigs;
if (!d.readVarU32(&numSigs))
return Fail(cx, d, "expected number of signatures");
if (numSigs > MaxSigs)
return Fail(cx, d, "too many signatures");
if (!init->sigs.resize(numSigs))
return false;
if (!init->sigToTable.resize(numSigs))
return false;
SigSet dupSet(cx);
if (!dupSet.init())
return false;
for (uint32_t sigIndex = 0; sigIndex < numSigs; sigIndex++) {
uint32_t numArgs;
if (!d.readVarU32(&numArgs))
return Fail(cx, d, "bad number of signature args");
if (numArgs > MaxArgsPerFunc)
return Fail(cx, d, "too many arguments in signature");
ExprType result;
if (!d.readExprType(&result))
return Fail(cx, d, "bad expression type");
if (!CheckExprType(cx, d, result))
return false;
ValTypeVector args;
if (!args.resize(numArgs))
return false;
for (uint32_t i = 0; i < numArgs; i++) {
if (!d.readValType(&args[i]))
return Fail(cx, d, "bad value type");
if (!CheckValType(cx, d, args[i]))
return false;
}
init->sigs[sigIndex] = Sig(Move(args), result);
SigSet::AddPtr p = dupSet.lookupForAdd(init->sigs[sigIndex]);
if (p)
return Fail(cx, d, "duplicate signature");
if (!dupSet.add(p, &init->sigs[sigIndex]))
return false;
}
if (!d.finishSection(sectionStart))
return Fail(cx, d, "decls section byte size mismatch");
return true;
}
