void WASMModuleParser::parseModule(ExecState* exec)
{
uint32_t magicNumber;
READ_UINT32_OR_FAIL(magicNumber, "Cannot read the magic number.");
FAIL_IF_FALSE(magicNumber == wasmMagicNumber, "The magic number is incorrect.");
uint32_t outputSizeInASMJS;
READ_UINT32_OR_FAIL(outputSizeInASMJS, "Cannot read the output size in asm.js format.");
parseConstantPoolSection();
PROPAGATE_ERROR();
parseSignatureSection();
PROPAGATE_ERROR();
parseFunctionImportSection(exec);
PROPAGATE_ERROR();
parseGlobalSection(exec);
PROPAGATE_ERROR();
parseFunctionDeclarationSection();
PROPAGATE_ERROR();
parseFunctionPointerTableSection();
PROPAGATE_ERROR();
parseFunctionDefinitionSection();
PROPAGATE_ERROR();
parseExportSection();
PROPAGATE_ERROR();
FAIL_IF_FALSE(!m_module->arrayBuffer() || m_module->arrayBuffer()->impl()->byteLength() < (1u << 31), "The ArrayBuffer's length must be less than 2^31.");
}
void WASMModuleParser::parseExportSection()
{
WASMExportFormat exportFormat;
READ_EXPORT_FORMAT_OR_FAIL(exportFormat, "Cannot read the export format.");
switch (exportFormat) {
case WASMExportFormat::Default: {
uint32_t functionIndex;
READ_COMPACT_UINT32_OR_FAIL(functionIndex, "Cannot read the function index.");
FAIL_IF_FALSE(functionIndex < m_module->functionDeclarations().size(), "The function index is incorrect.");
// FIXME: Export the function.
break;
}
case WASMExportFormat::Record: {
uint32_t numberOfExports;
READ_COMPACT_UINT32_OR_FAIL(numberOfExports, "Cannot read the number of exports.");
for (uint32_t exportIndex = 0; exportIndex < numberOfExports; ++exportIndex) {
String exportName;
READ_STRING_OR_FAIL(exportName, "Cannot read the function export name.");
// FIXME: Check that exportName is legal.
uint32_t functionIndex;
READ_COMPACT_UINT32_OR_FAIL(functionIndex, "Cannot read the function index.");
FAIL_IF_FALSE(functionIndex < m_module->functionDeclarations().size(), "The function index is incorrect.");
// FIXME: Export the function.
}
break;
}
default:
ASSERT_NOT_REACHED();
}
}
void WASMModuleParser::parseFunctionImportSection()
{
uint32_t numberOfFunctionImports;
uint32_t numberOfFunctionImportSignatures;
READ_COMPACT_UINT32_OR_FAIL(numberOfFunctionImports, "Cannot read the number of function imports.");
READ_COMPACT_UINT32_OR_FAIL(numberOfFunctionImportSignatures, "Cannot read the number of function import signatures.");
m_module->functionImports().reserveInitialCapacity(numberOfFunctionImports);
m_module->functionImportSignatures().reserveInitialCapacity(numberOfFunctionImportSignatures);
for (uint32_t functionImportIndex = 0; functionImportIndex < numberOfFunctionImports; ++functionImportIndex) {
WASMFunctionImport functionImport;
READ_STRING_OR_FAIL(functionImport.functionName, "Cannot read the function import name.");
m_module->functionImports().uncheckedAppend(functionImport);
uint32_t numberOfSignatures;
READ_COMPACT_UINT32_OR_FAIL(numberOfSignatures, "Cannot read the number of signatures.");
FAIL_IF_FALSE(numberOfSignatures <= numberOfFunctionImportSignatures - m_module->functionImportSignatures().size(), "The number of signatures is incorrect.");
for (uint32_t i = 0; i < numberOfSignatures; ++i) {
WASMFunctionImportSignature functionImportSignature;
READ_COMPACT_UINT32_OR_FAIL(functionImportSignature.signatureIndex, "Cannot read the signature index.");
FAIL_IF_FALSE(functionImportSignature.signatureIndex < m_module->signatures().size(), "The signature index is incorrect.");
functionImportSignature.functionImportIndex = functionImportIndex;
m_module->functionImportSignatures().uncheckedAppend(functionImportSignature);
}
}
FAIL_IF_FALSE(m_module->functionImportSignatures().size() == numberOfFunctionImportSignatures, "The number of function import signatures is incorrect.");
}
void WASMModuleParser::getImportedValue(ExecState* exec, const String& importName, JSValue& value)
{
FAIL_IF_FALSE(m_imports, "Accessing property of non-object.");
Identifier identifier = Identifier::fromString(&m_vm, importName);
PropertySlot slot(m_imports.get(), PropertySlot::InternalMethodType::Get);
if (!m_imports->getPropertySlot(exec, identifier, slot))
FAIL_WITH_MESSAGE("Can't find a property named \"" + importName + '"');
FAIL_IF_FALSE(slot.isValue(), "\"" + importName + "\" is not a data property.");
// We only retrieve data properties. So, this does not cause any user-observable effect.
value = slot.getValue(exec, identifier);
}
void WASMModuleParser::parseModule()
{
uint32_t magicNumber;
READ_UINT32_OR_FAIL(magicNumber, "Cannot read the magic number.");
FAIL_IF_FALSE(magicNumber == wasmMagicNumber, "The magic number is incorrect.");
uint32_t outputSizeInASMJS;
READ_UINT32_OR_FAIL(outputSizeInASMJS, "Cannot read the output size in asm.js format.");
parseConstantPoolSection();
PROPAGATE_ERROR();
parseSignatureSection();
PROPAGATE_ERROR();
parseFunctionImportSection();
PROPAGATE_ERROR();
parseGlobalSection();
PROPAGATE_ERROR();
parseFunctionDeclarationSection();
PROPAGATE_ERROR();
parseFunctionPointerTableSection();
PROPAGATE_ERROR();
parseFunctionDefinitionSection();
PROPAGATE_ERROR();
parseExportSection();
}
ContextStatement WASMFunctionParser::parseContinueLabelStatement(Context&)
{
uint32_t labelIndex;
READ_COMPACT_UINT32_OR_FAIL(labelIndex, "Cannot read the label index.");
FAIL_IF_FALSE(labelIndex < m_labelDepth, "The label index is incorrect.");
// FIXME: Implement this instruction.
return UNUSED;
}
ContextStatement WASMFunctionParser::parseSetLocalStatement(Context& context, uint32_t localIndex)
{
FAIL_IF_FALSE(localIndex < m_localTypes.size(), "The local variable index is incorrect.");
WASMType type = m_localTypes[localIndex];
parseExpression(context, WASMExpressionType(type));
// FIXME: Implement this instruction.
return UNUSED;
}
void WASMModuleParser::parseFunctionPointerTableSection()
{
uint32_t numberOfFunctionPointerTables;
READ_COMPACT_UINT32_OR_FAIL(numberOfFunctionPointerTables, "Cannot read the number of function pointer tables.");
m_module->functionPointerTables().reserveInitialCapacity(numberOfFunctionPointerTables);
for (uint32_t i = 0; i < numberOfFunctionPointerTables; ++i) {
WASMFunctionPointerTable functionPointerTable;
READ_COMPACT_UINT32_OR_FAIL(functionPointerTable.signatureIndex, "Cannot read the signature index.");
FAIL_IF_FALSE(functionPointerTable.signatureIndex < m_module->signatures().size(), "The signature index is incorrect.");
uint32_t numberOfElements;
READ_COMPACT_UINT32_OR_FAIL(numberOfElements, "Cannot read the number of elements of a function pointer table.");
FAIL_IF_FALSE(hasOneBitSet(numberOfElements), "The number of elements must be a power of two.");
functionPointerTable.elements.reserveInitialCapacity(numberOfElements);
for (uint32_t j = 0; j < numberOfElements; ++j) {
uint32_t element;
READ_COMPACT_UINT32_OR_FAIL(element, "Cannot read an element of a function pointer table.");
functionPointerTable.elements.uncheckedAppend(element);
}
m_module->functionPointerTables().uncheckedAppend(functionPointerTable);
}
}
void WASMModuleParser::parseFunctionDeclarationSection()
{
uint32_t numberOfFunctionDeclarations;
READ_COMPACT_UINT32_OR_FAIL(numberOfFunctionDeclarations, "Cannot read the number of function declarations.");
m_module->functionDeclarations().reserveInitialCapacity(numberOfFunctionDeclarations);
for (uint32_t i = 0; i < numberOfFunctionDeclarations; ++i) {
WASMFunctionDeclaration functionDeclaration;
READ_COMPACT_UINT32_OR_FAIL(functionDeclaration.signatureIndex, "Cannot read the signature index.");
FAIL_IF_FALSE(functionDeclaration.signatureIndex < m_module->signatures().size(), "The signature index is incorrect.");
m_module->functionDeclarations().uncheckedAppend(functionDeclaration);
}
}
void WASMModuleParser::parseFunctionDefinition()
{
// FIXME: Support any functions. https://bugs.webkit.org/show_bug.cgi?id=147738
// Currently, we only support functions that have "return 0;" as their only statement.
// These functions consist of exactly 4 bytes, i.e.
// 1. The number of local variables (0) [0x80]
// 2. The number of statements (1) [0x01]
// 3. The return statement [0x0f]
// 4. The immediate expression (0) [0xa0]
uint32_t functionDefinitionBytes;
READ_UINT32_OR_FAIL(functionDefinitionBytes, "Cannot read the function definition.");
FAIL_IF_FALSE(functionDefinitionBytes == 0xa00f0180, "Only functions that have \"return 0;\" "
"as their only statement are supported at the moment.");
}
void WASMModuleParser::parseFunctionPointerTableSection()
{
uint32_t numberOfFunctionPointerTables;
READ_COMPACT_UINT32_OR_FAIL(numberOfFunctionPointerTables, "Cannot read the number of function pointer tables.");
m_module->functionPointerTables().reserveInitialCapacity(numberOfFunctionPointerTables);
for (uint32_t i = 0; i < numberOfFunctionPointerTables; ++i) {
WASMFunctionPointerTable functionPointerTable;
READ_COMPACT_UINT32_OR_FAIL(functionPointerTable.signatureIndex, "Cannot read the signature index.");
FAIL_IF_FALSE(functionPointerTable.signatureIndex < m_module->signatures().size(), "The signature index is incorrect.");
uint32_t numberOfFunctions;
READ_COMPACT_UINT32_OR_FAIL(numberOfFunctions, "Cannot read the number of functions of a function pointer table.");
FAIL_IF_FALSE(hasOneBitSet(numberOfFunctions), "The number of functions must be a power of two.");
functionPointerTable.functionIndices.reserveInitialCapacity(numberOfFunctions);
functionPointerTable.functions.reserveInitialCapacity(numberOfFunctions);
for (uint32_t j = 0; j < numberOfFunctions; ++j) {
uint32_t functionIndex;
READ_COMPACT_UINT32_OR_FAIL(functionIndex, "Cannot read a function index of a function pointer table.");
FAIL_IF_FALSE(functionIndex < m_module->functionDeclarations().size(), "The function index is incorrect.");
FAIL_IF_FALSE(m_module->functionDeclarations()[functionIndex].signatureIndex == functionPointerTable.signatureIndex, "The signature of the function doesn't match that of the function pointer table.");
functionPointerTable.functionIndices.uncheckedAppend(functionIndex);
}
m_module->functionPointerTables().uncheckedAppend(functionPointerTable);
}
}
void WASMModuleParser::parseFunctionImportSection(ExecState* exec)
{
uint32_t numberOfFunctionImports;
uint32_t numberOfFunctionImportSignatures;
READ_COMPACT_UINT32_OR_FAIL(numberOfFunctionImports, "Cannot read the number of function imports.");
READ_COMPACT_UINT32_OR_FAIL(numberOfFunctionImportSignatures, "Cannot read the number of function import signatures.");
m_module->functionImports().reserveInitialCapacity(numberOfFunctionImports);
m_module->functionImportSignatures().reserveInitialCapacity(numberOfFunctionImportSignatures);
m_module->importedFunctions().reserveInitialCapacity(numberOfFunctionImports);
for (uint32_t functionImportIndex = 0; functionImportIndex < numberOfFunctionImports; ++functionImportIndex) {
WASMFunctionImport functionImport;
READ_STRING_OR_FAIL(functionImport.functionName, "Cannot read the function import name.");
m_module->functionImports().uncheckedAppend(functionImport);
uint32_t numberOfSignatures;
READ_COMPACT_UINT32_OR_FAIL(numberOfSignatures, "Cannot read the number of signatures.");
FAIL_IF_FALSE(numberOfSignatures <= numberOfFunctionImportSignatures - m_module->functionImportSignatures().size(), "The number of signatures is incorrect.");
for (uint32_t i = 0; i < numberOfSignatures; ++i) {
WASMFunctionImportSignature functionImportSignature;
READ_COMPACT_UINT32_OR_FAIL(functionImportSignature.signatureIndex, "Cannot read the signature index.");
FAIL_IF_FALSE(functionImportSignature.signatureIndex < m_module->signatures().size(), "The signature index is incorrect.");
functionImportSignature.functionImportIndex = functionImportIndex;
m_module->functionImportSignatures().uncheckedAppend(functionImportSignature);
}
JSValue value;
getImportedValue(exec, functionImport.functionName, value);
PROPAGATE_ERROR();
FAIL_IF_FALSE(value.isFunction(), "\"" + functionImport.functionName + "\" is not a function.");
JSFunction* function = jsCast<JSFunction*>(value.asCell());
m_module->importedFunctions().uncheckedAppend(WriteBarrier<JSFunction>(m_vm, m_module.get(), function));
}
FAIL_IF_FALSE(m_module->functionImportSignatures().size() == numberOfFunctionImportSignatures, "The number of function import signatures is incorrect.");
}
ContextStatement WASMFunctionParser::parseSwitchStatement(Context& context)
{
uint32_t numberOfCases;
READ_COMPACT_UINT32_OR_FAIL(numberOfCases, "Cannot read the number of cases.");
parseExpressionI32(context);
PROPAGATE_ERROR();
m_breakScopeDepth++;
for (uint32_t i = 0; i < numberOfCases; ++i) {
WASMSwitchCase switchCase;
READ_SWITCH_CASE_OR_FAIL(switchCase, "Cannot read the switch case.");
switch (switchCase) {
case WASMSwitchCase::CaseWithNoStatements:
case WASMSwitchCase::CaseWithStatement:
case WASMSwitchCase::CaseWithBlockStatement: {
uint32_t value;
READ_COMPACT_INT32_OR_FAIL(value, "Cannot read the value of the switch case.");
if (switchCase == WASMSwitchCase::CaseWithStatement) {
parseStatement(context);
PROPAGATE_ERROR();
} else if (switchCase == WASMSwitchCase::CaseWithBlockStatement) {
parseBlockStatement(context);
PROPAGATE_ERROR();
}
break;
}
case WASMSwitchCase::DefaultWithNoStatements:
case WASMSwitchCase::DefaultWithStatement:
case WASMSwitchCase::DefaultWithBlockStatement: {
FAIL_IF_FALSE(i == numberOfCases - 1, "The default case must be the last case.");
if (switchCase == WASMSwitchCase::DefaultWithStatement) {
parseStatement(context);
PROPAGATE_ERROR();
} else if (switchCase == WASMSwitchCase::DefaultWithBlockStatement) {
parseBlockStatement(context);
PROPAGATE_ERROR();
}
break;
}
default:
ASSERT_NOT_REACHED();
}
}
m_breakScopeDepth--;
// FIXME: Implement this instruction.
return UNUSED;
}
void WASMModuleParser::parseGlobalSection(ExecState* exec)
{
uint32_t numberOfInternalI32GlobalVariables;
uint32_t numberOfInternalF32GlobalVariables;
uint32_t numberOfInternalF64GlobalVariables;
uint32_t numberOfImportedI32GlobalVariables;
uint32_t numberOfImportedF32GlobalVariables;
uint32_t numberOfImportedF64GlobalVariables;
READ_COMPACT_UINT32_OR_FAIL(numberOfInternalI32GlobalVariables, "Cannot read the number of internal int32 global variables.");
READ_COMPACT_UINT32_OR_FAIL(numberOfInternalF32GlobalVariables, "Cannot read the number of internal float32 global variables.");
READ_COMPACT_UINT32_OR_FAIL(numberOfInternalF64GlobalVariables, "Cannot read the number of internal float64 global variables.");
READ_COMPACT_UINT32_OR_FAIL(numberOfImportedI32GlobalVariables, "Cannot read the number of imported int32 global variables.");
READ_COMPACT_UINT32_OR_FAIL(numberOfImportedF32GlobalVariables, "Cannot read the number of imported float32 global variables.");
READ_COMPACT_UINT32_OR_FAIL(numberOfImportedF64GlobalVariables, "Cannot read the number of imported float64 global variables.");
uint32_t numberOfGlobalVariables = numberOfInternalI32GlobalVariables + numberOfInternalF32GlobalVariables + numberOfInternalF64GlobalVariables +
numberOfImportedI32GlobalVariables + numberOfImportedF32GlobalVariables + numberOfImportedF64GlobalVariables;
Vector<WASMType>& globalVariableTypes = m_module->globalVariableTypes();
globalVariableTypes.reserveInitialCapacity(numberOfGlobalVariables);
Vector<JSWASMModule::GlobalVariable>& globalVariables = m_module->globalVariables();
globalVariables.reserveInitialCapacity(numberOfGlobalVariables);
for (uint32_t i = 0; i < numberOfInternalI32GlobalVariables; ++i) {
globalVariableTypes.uncheckedAppend(WASMType::I32);
globalVariables.uncheckedAppend(JSWASMModule::GlobalVariable(0));
}
for (uint32_t i = 0; i < numberOfInternalF32GlobalVariables; ++i) {
globalVariableTypes.uncheckedAppend(WASMType::F32);
globalVariables.uncheckedAppend(JSWASMModule::GlobalVariable(0.0f));
}
for (uint32_t i = 0; i < numberOfInternalF64GlobalVariables; ++i) {
globalVariableTypes.uncheckedAppend(WASMType::F64);
globalVariables.uncheckedAppend(JSWASMModule::GlobalVariable(0.0));
}
for (uint32_t i = 0; i < numberOfImportedI32GlobalVariables; ++i) {
String importName;
READ_STRING_OR_FAIL(importName, "Cannot read the import name of an int32 global variable.");
globalVariableTypes.uncheckedAppend(WASMType::I32);
JSValue value;
getImportedValue(exec, importName, value);
PROPAGATE_ERROR();
FAIL_IF_FALSE(value.isPrimitive() && !value.isSymbol(), "\"" + importName + "\" is not a primitive or is a Symbol.");
globalVariables.uncheckedAppend(JSWASMModule::GlobalVariable(value.toInt32(exec)));
}
for (uint32_t i = 0; i < numberOfImportedF32GlobalVariables; ++i) {
String importName;
READ_STRING_OR_FAIL(importName, "Cannot read the import name of a float32 global variable.");
globalVariableTypes.uncheckedAppend(WASMType::F32);
JSValue value;
getImportedValue(exec, importName, value);
PROPAGATE_ERROR();
FAIL_IF_FALSE(value.isPrimitive() && !value.isSymbol(), "\"" + importName + "\" is not a primitive or is a Symbol.");
globalVariables.uncheckedAppend(JSWASMModule::GlobalVariable(static_cast<float>(value.toNumber(exec))));
}
for (uint32_t i = 0; i < numberOfImportedF64GlobalVariables; ++i) {
String importName;
READ_STRING_OR_FAIL(importName, "Cannot read the import name of a float64 global variable.");
globalVariableTypes.uncheckedAppend(WASMType::F64);
JSValue value;
getImportedValue(exec, importName, value);
PROPAGATE_ERROR();
FAIL_IF_FALSE(value.isPrimitive() && !value.isSymbol(), "\"" + importName + "\" is not a primitive or is a Symbol.");
globalVariables.uncheckedAppend(JSWASMModule::GlobalVariable(value.toNumber(exec)));
}
}
ContextStatement WASMFunctionParser::parseContinueStatement(Context&)
{
FAIL_IF_FALSE(m_continueScopeDepth, "'continue' is only valid inside a loop statement.");
// FIXME: Implement this instruction.
return UNUSED;
}
ContextStatement WASMFunctionParser::parseBreakStatement(Context&)
{
FAIL_IF_FALSE(m_breakScopeDepth, "'break' is only valid inside a switch or loop statement.");
// FIXME: Implement this instruction.
return UNUSED;
}
