Example #1
JS_GetScriptSourceMap(JSContext *cx, JSScript *script)
    ScriptSource *source = script->scriptSource();
    return source->hasSourceMapURL() ? source->sourceMapURL() : nullptr;
Example #2
frontend::CompileScript(ExclusiveContext* cx, LifoAlloc* alloc, HandleObject scopeChain,
                        HandleScript evalCaller,
                        Handle<StaticEvalObject*> evalStaticScope,
                        const ReadOnlyCompileOptions& options,
                        SourceBufferHolder& srcBuf,
                        JSString* source_ /* = nullptr */,
                        unsigned staticLevel /* = 0 */,
                        SourceCompressionTask* extraSct /* = nullptr */)

    RootedString source(cx, source_);

    js::TraceLoggerThread* logger = nullptr;
    if (cx->isJSContext())
        logger = TraceLoggerForMainThread(cx->asJSContext()->runtime());
        logger = TraceLoggerForCurrentThread();
    js::TraceLoggerEvent event(logger, TraceLogger_AnnotateScripts, options);
    js::AutoTraceLog scriptLogger(logger, event);
    js::AutoTraceLog typeLogger(logger, TraceLogger_ParserCompileScript);

     * The scripted callerFrame can only be given for compile-and-go scripts
     * and non-zero static level requires callerFrame.
    MOZ_ASSERT_IF(evalCaller, options.compileAndGo);
    MOZ_ASSERT_IF(evalCaller, options.forEval);
    MOZ_ASSERT_IF(evalCaller && evalCaller->strict(), options.strictOption);
    MOZ_ASSERT_IF(staticLevel != 0, evalCaller);

    if (!CheckLength(cx, srcBuf))
        return nullptr;
    MOZ_ASSERT_IF(staticLevel != 0, !options.sourceIsLazy);

    RootedScriptSource sourceObject(cx, CreateScriptSourceObject(cx, options));
    if (!sourceObject)
        return nullptr;

    ScriptSource* ss = sourceObject->source();

    SourceCompressionTask mysct(cx);
    SourceCompressionTask* sct = extraSct ? extraSct : &mysct;

    if (!cx->compartment()->options().discardSource()) {
        if (options.sourceIsLazy)
        else if (!ss->setSourceCopy(cx, srcBuf, false, sct))
            return nullptr;

    bool canLazilyParse = CanLazilyParse(cx, options);

    Maybe<Parser<SyntaxParseHandler> > syntaxParser;
    if (canLazilyParse) {
        syntaxParser.emplace(cx, alloc, options, srcBuf.get(), srcBuf.length(),
                             /* foldConstants = */ false,
                             (Parser<SyntaxParseHandler>*) nullptr,
                             (LazyScript*) nullptr);

        if (!syntaxParser->checkOptions())
            return nullptr;

    Parser<FullParseHandler> parser(cx, alloc, options, srcBuf.get(), srcBuf.length(),
                                    /* foldConstants = */ true,
                                    canLazilyParse ? syntaxParser.ptr() : nullptr, nullptr);
    parser.sct = sct;
    parser.ss = ss;

    if (!parser.checkOptions())
        return nullptr;

    Directives directives(options.strictOption);
    GlobalSharedContext globalsc(cx, scopeChain, directives, options.extraWarningsOption);

    bool savedCallerFun = evalCaller && evalCaller->functionOrCallerFunction();
    Rooted<JSScript*> script(cx, JSScript::Create(cx, evalStaticScope, savedCallerFun,
                                                  options, staticLevel, sourceObject, 0,
    if (!script)
        return nullptr;

    // We can specialize a bit for the given scope chain if that scope chain is the global object.
    JSObject* globalScope =
        scopeChain && scopeChain == &scopeChain->global() ? (JSObject*) scopeChain : nullptr;
    MOZ_ASSERT_IF(globalScope, globalScope->isNative());
    MOZ_ASSERT_IF(globalScope, JSCLASS_HAS_GLOBAL_FLAG_AND_SLOTS(globalScope->getClass()));

    BytecodeEmitter::EmitterMode emitterMode =
        options.selfHostingMode ? BytecodeEmitter::SelfHosting : BytecodeEmitter::Normal;
    BytecodeEmitter bce(/* parent = */ nullptr, &parser, &globalsc, script,
                        /* lazyScript = */ js::NullPtr(), options.forEval,
                        evalCaller, evalStaticScope, !!globalScope, options.lineno, emitterMode);
    if (!bce.init())
        return nullptr;

    // Syntax parsing may cause us to restart processing of top level
    // statements in the script. Use Maybe<> so that the parse context can be
    // reset when this occurs.
    Maybe<ParseContext<FullParseHandler> > pc;

    pc.emplace(&parser, (GenericParseContext*) nullptr, (ParseNode*) nullptr, &globalsc,
               (Directives*) nullptr, staticLevel, /* bodyid = */ 0,
               /* blockScopeDepth = */ 0);
    if (!pc->init(parser.tokenStream))
        return nullptr;

    if (savedCallerFun) {
         * An eval script in a caller frame needs to have its enclosing
         * function captured in case it refers to an upvar, and someone
         * wishes to decompile it while it's running.
        JSFunction* fun = evalCaller->functionOrCallerFunction();
        MOZ_ASSERT_IF(fun->strict(), options.strictOption);
        Directives directives(/* strict = */ options.strictOption);
        ObjectBox* funbox = parser.newFunctionBox(/* fn = */ nullptr, fun, pc.ptr(),
                                                  directives, fun->generatorKind());
        if (!funbox)
            return nullptr;

    bool canHaveDirectives = true;
    for (;;) {
        TokenKind tt;
        if (!parser.tokenStream.peekToken(&tt, TokenStream::Operand))
            return nullptr;
        if (tt == TOK_EOF)

        TokenStream::Position pos(parser.keepAtoms);

        ParseNode* pn = parser.statement(canHaveDirectives);
        if (!pn) {
            if (parser.hadAbortedSyntaxParse()) {
                // Parsing inner functions lazily may lead the parser into an
                // unrecoverable state and may require starting over on the top
                // level statement. Restart the parse; syntax parsing has
                // already been disabled for the parser and the result will not
                // be ambiguous.

                // Destroying the parse context will destroy its free
                // variables, so check if any deoptimization is needed.
                if (!MaybeCheckEvalFreeVariables(cx, evalCaller, scopeChain, parser, *pc))
                    return nullptr;

                pc.emplace(&parser, (GenericParseContext*) nullptr, (ParseNode*) nullptr,
                           &globalsc, (Directives*) nullptr, staticLevel, /* bodyid = */ 0,
                if (!pc->init(parser.tokenStream))
                    return nullptr;
                MOZ_ASSERT(parser.pc == pc.ptr());

                pn = parser.statement();
            if (!pn) {
                return nullptr;

        // Accumulate the maximum block scope depth, so that EmitTree can assert
        // when emitting JSOP_GETLOCAL that the local is indeed within the fixed
        // part of the stack frame.

        if (canHaveDirectives) {
            if (!parser.maybeParseDirective(/* stmtList = */ nullptr, pn, &canHaveDirectives))
                return nullptr;

        if (!FoldConstants(cx, &pn, &parser))
            return nullptr;

        if (!NameFunctions(cx, pn))
            return nullptr;

        if (!bce.updateLocalsToFrameSlots())
            return nullptr;

        if (!EmitTree(cx, &bce, pn))
            return nullptr;


    if (!MaybeCheckEvalFreeVariables(cx, evalCaller, scopeChain, parser, *pc))
        return nullptr;

    if (!SetDisplayURL(cx, parser.tokenStream, ss))
        return nullptr;

    if (!SetSourceMap(cx, parser.tokenStream, ss))
        return nullptr;

     * Source map URLs passed as a compile option (usually via a HTTP source map
     * header) override any source map urls passed as comment pragmas.
    if (options.sourceMapURL()) {
        // Warn about the replacement, but use the new one.
        if (ss->hasSourceMapURL()) {
            if(!parser.report(ParseWarning, false, nullptr, JSMSG_ALREADY_HAS_PRAGMA,
                              ss->filename(), "//# sourceMappingURL"))
                return nullptr;

        if (!ss->setSourceMapURL(cx, options.sourceMapURL()))
            return nullptr;

     * Nowadays the threaded interpreter needs a last return instruction, so we
     * do have to emit that here.
    if (Emit1(cx, &bce, JSOP_RETRVAL) < 0)
        return nullptr;

    // Global/eval script bindings are always empty (all names are added to the
    // scope dynamically via JSOP_DEFFUN/VAR).  They may have block-scoped
    // locals, however, which are allocated to the fixed part of the stack
    // frame.
    InternalHandle<Bindings*> bindings(script, &script->bindings);
    if (!Bindings::initWithTemporaryStorage(cx, bindings, 0, 0, 0,
                                            pc->blockScopeDepth, 0, 0, nullptr))
        return nullptr;

    if (!JSScript::fullyInitFromEmitter(cx, script, &bce))
        return nullptr;

    // Note that this marking must happen before we tell Debugger
    // about the new script, in case Debugger delazifies the script's
    // inner functions.
    if (options.forEval)


    if (sct && !extraSct && !sct->complete())
        return nullptr;

    MOZ_ASSERT_IF(cx->isJSContext(), !cx->asJSContext()->isExceptionPending());
    return script;