Examples with LexicalEnvironment com.github.anba.es6draft.runtime.LexicalEnvironment used on opensource projects

Example 11 with LexicalEnvironment

use of com.github.anba.es6draft.runtime.LexicalEnvironment in project es6draft by anba.

the class StatementGenerator method visit.

/**
 * 13.7.2 The do-while Statement
 * <p>
 * 13.1.8 Runtime Semantics: Evaluation<br>
 * 13.1.7 Runtime Semantics: LabelledEvaluation<br>
 * 13.7.2.6 Runtime Semantics: LabelledEvaluation
 */
@Override
public Completion visit(DoWhileStatement node, CodeVisitor mv) {
    assert mv.getStackSize() == 0;
    Jump lblNext = new Jump();
    ContinueLabel lblContinue = new ContinueLabel();
    BreakLabel lblBreak = new BreakLabel();
    Bool btest = Bool.evaluate(node.getTest());
    mv.enterVariableScope();
    Variable<LexicalEnvironment<?>> savedEnv = saveEnvironment(node, mv);
    /* step 1 */
    if (node.hasCompletionValue()) {
        mv.storeUndefinedAsCompletionValue();
    }
    /* step 2 (repeat loop) */
    mv.mark(lblNext);
    /* steps 2.a-c */
    Completion result;
    {
        mv.enterIteration(node, lblBreak, lblContinue);
        result = node.getStatement().accept(this, mv);
        mv.exitIteration(node);
    }
    /* step 2.b (abrupt completion - continue) */
    if (lblContinue.isTarget()) {
        mv.mark(lblContinue);
        restoreEnvironment(savedEnv, mv);
    }
    /* steps 2.d-g */
    if (!result.isAbrupt() || lblContinue.isTarget()) {
        if (btest == Bool.Any) {
            testExpressionFallthrough(node.getTest(), lblNext, mv);
        } else if (btest == Bool.True) {
            mv.goTo(lblNext);
        }
    }
    /* step 2.b (abrupt completion - break) */
    if (lblBreak.isTarget()) {
        mv.mark(lblBreak);
        restoreEnvironment(savedEnv, mv);
    }
    mv.exitVariableScope();
    /* steps 2.b, 2.g */
    if (btest == Bool.True && !lblBreak.isTarget()) {
        // abrupt or infinite loop
        return Completion.Abrupt;
    }
    return result.normal(lblContinue.isTarget() || lblBreak.isTarget());
}

Example 12 with LexicalEnvironment

use of com.github.anba.es6draft.runtime.LexicalEnvironment in project es6draft by anba.

the class SwitchStatementGenerator method visit.

/**
 * 13.12.11 Runtime Semantics: Evaluation
 */
@Override
public Completion visit(SwitchStatement node, CodeVisitor mv) {
    final boolean defaultClausePresent = hasDefaultClause(node);
    final SwitchType type = SwitchType.of(node);
    // stack -> switchValue
    ValType switchValueType = expression(node.getExpression(), mv);
    boolean defaultOrReturn = false;
    if (isDefaultSwitch(node)) {
        defaultOrReturn = true;
    } else if (type == SwitchType.Int) {
        if (!switchValueType.isNumber() && switchValueType != ValType.Any) {
            defaultOrReturn = true;
        }
    } else if (type == SwitchType.Char) {
        if (switchValueType != ValType.String && switchValueType != ValType.Any) {
            defaultOrReturn = true;
        }
    } else if (type == SwitchType.String) {
        if (switchValueType != ValType.String && switchValueType != ValType.Any) {
            defaultOrReturn = true;
        }
    } else {
        mv.toBoxed(switchValueType);
        switchValueType = ValType.Any;
    }
    if (defaultOrReturn) {
        // never true -> emit default switch or return
        mv.pop(switchValueType);
        if (!defaultClausePresent) {
            return Completion.Normal;
        }
    }
    mv.enterVariableScope();
    Variable<LexicalEnvironment<?>> savedEnv = saveEnvironment(node, mv);
    Variable<?> switchValue = null;
    if (!defaultOrReturn) {
        switchValue = mv.newVariable("switchValue", switchValueType.toClass());
        mv.store(switchValue);
    }
    BlockScope scope = node.getScope();
    if (scope.isPresent()) {
        newDeclarativeEnvironment(scope, mv);
        codegen.blockInit(node, mv);
        pushLexicalEnvironment(mv);
    }
    Jump lblExit = new Jump();
    BreakLabel lblBreak = new BreakLabel();
    mv.enterScope(node);
    mv.enterBreakable(node, lblBreak);
    Completion result;
    if (defaultOrReturn) {
        result = DefaultCaseBlockEvaluation(node, mv);
    } else {
        result = CaseBlockEvaluation(node, type, defaultClausePresent, lblExit, switchValue, mv);
    }
    mv.exitBreakable(node);
    mv.exitScope();
    if (!defaultClausePresent) {
        mv.mark(lblExit);
    }
    if (scope.isPresent() && !result.isAbrupt()) {
        popLexicalEnvironment(mv);
    }
    if (lblBreak.isTarget()) {
        mv.mark(lblBreak);
        restoreEnvironment(savedEnv, mv);
    }
    mv.exitVariableScope();
    return result.normal(lblBreak.isTarget() || !defaultClausePresent);
}

Example 13 with LexicalEnvironment

use of com.github.anba.es6draft.runtime.LexicalEnvironment in project es6draft by anba.

the class BlockDeclarationInstantiationGenerator method generateOrSplit.

private void generateOrSplit(Node node, List<Declaration> declarations, HashSet<Name> instantiatedNames, BlockInstantiationVisitor mv) {
    Variable<ExecutionContext> cx = mv.getExecutionContext();
    Variable<LexicalEnvironment<DeclarativeEnvironmentRecord>> env = mv.getLexicalEnvironment();
    if (declarations.size() <= METHOD_LIMIT) {
        generate(declarations, instantiatedNames, cx, env, mv);
    } else {
        for (int i = 0, size = declarations.size(); i < size; i += METHOD_LIMIT) {
            List<Declaration> sublist = declarations.subList(i, Math.min(i + METHOD_LIMIT, size));
            MethodName method = compile(node, sublist, instantiatedNames);
            mv.load(env);
            mv.load(cx);
            mv.invoke(method);
        }
    }
}

Example 14 with LexicalEnvironment

use of com.github.anba.es6draft.runtime.LexicalEnvironment in project es6draft by anba.

the class ComprehensionGenerator method visit.

/**
 * Runtime Semantics: ComprehensionComponentEvaluation
 * <p>
 * ComprehensionFor : for ( ForBinding of AssignmentExpression )
 */
@Override
public Void visit(ComprehensionFor node, CodeVisitor mv) {
    Jump lblTest = new Jump(), lblLoop = new Jump();
    Variable<ScriptIterator<?>> iter = iterators.next();
    /* steps 1-2 */
    expressionBoxed(node.getExpression(), mv);
    /* steps 3-4 */
    mv.loadExecutionContext();
    mv.lineInfo(node.getExpression());
    mv.invoke(Methods.IteratorOperations_iterate);
    mv.store(iter);
    /* step 5 (not applicable) */
    /* step 6 */
    mv.nonDestructiveGoTo(lblTest);
    /* steps 6.d-e */
    mv.mark(lblLoop);
    mv.load(iter);
    mv.lineInfo(node);
    mv.invoke(Methods.Iterator_next);
    /* steps 6.f-j */
    BlockScope scope = node.getScope();
    if (scope.isPresent()) {
        mv.enterVariableScope();
        Variable<LexicalEnvironment<DeclarativeEnvironmentRecord>> env = mv.newVariable("env", LexicalEnvironment.class).uncheckedCast();
        Variable<DeclarativeEnvironmentRecord> envRec = mv.newVariable("envRec", DeclarativeEnvironmentRecord.class);
        // stack: [nextValue] -> []
        Variable<Object> nextValue = mv.newVariable("nextValue", Object.class);
        mv.store(nextValue);
        newDeclarativeEnvironment(scope, mv);
        mv.store(env);
        getEnvRec(env, envRec, mv);
        for (Name name : BoundNames(node.getBinding())) {
            BindingOp<DeclarativeEnvironmentRecord> op = BindingOp.of(envRec, name);
            op.createMutableBinding(envRec, name, false, mv);
        }
        BindingInitialization(codegen, envRec, node.getBinding(), nextValue, mv);
        mv.load(env);
        pushLexicalEnvironment(mv);
        mv.exitVariableScope();
    } else {
        // stack: [nextValue] -> []
        mv.pop();
    }
    /* step 6.k */
    mv.enterScope(node);
    new IterationGenerator<ComprehensionFor>(codegen) {

        @Override
        protected Completion iterationBody(ComprehensionFor node, Variable<ScriptIterator<?>> iterator, CodeVisitor mv) {
            elements.next().accept(ComprehensionGenerator.this, mv);
            return Completion.Normal;
        }

        @Override
        protected MutableValue<Object> enterIteration(ComprehensionFor node, CodeVisitor mv) {
            return mv.enterIteration();
        }

        @Override
        protected List<TempLabel> exitIteration(ComprehensionFor node, CodeVisitor mv) {
            return mv.exitIteration();
        }
    }.generate(node, iter, mv);
    mv.exitScope();
    /* steps 6.l-m */
    if (scope.isPresent()) {
        popLexicalEnvironment(mv);
    }
    /* steps 6.a-c */
    mv.mark(lblTest);
    mv.load(iter);
    mv.lineInfo(node);
    mv.invoke(Methods.Iterator_hasNext);
    mv.ifne(lblLoop);
    return null;
}

Example 15 with LexicalEnvironment

use of com.github.anba.es6draft.runtime.LexicalEnvironment in project es6draft by anba.

the class FunctionDeclarationInstantiationGenerator method generate.

private void generate(FunctionNode function, CodeVisitor mv) {
    Variable<ExecutionContext> context = mv.getParameter(EXECUTION_CONTEXT, ExecutionContext.class);
    Variable<LexicalEnvironment<FunctionEnvironmentRecord>> env = mv.newVariable("env", LexicalEnvironment.class).uncheckedCast();
    Variable<FunctionEnvironmentRecord> envRec = mv.newVariable("envRec", FunctionEnvironmentRecord.class);
    Variable<FunctionObject> fo = null;
    Variable<Undefined> undefined = mv.newVariable("undef", Undefined.class);
    mv.loadUndefined();
    mv.store(undefined);
    FunctionScope fscope = function.getScope();
    boolean hasParameters = !function.getParameters().getFormals().isEmpty();
    Variable<Iterator<?>> iterator = null;
    if (hasParameters) {
        iterator = mv.newVariable("iterator", Iterator.class).uncheckedCast();
        mv.loadParameter(ARGUMENTS, Object[].class);
        mv.invoke(Methods.Arrays_asList);
        mv.invoke(Methods.List_iterator);
        mv.store(iterator);
    }
    /* step 1 (omitted) */
    /* step 2 */
    getLexicalEnvironment(context, env, mv);
    /* step 3 */
    getEnvironmentRecord(env, envRec, mv);
    /* step 4 */
    // RuntimeInfo.Function code = func.getCode();
    /* step 5 */
    boolean strict = IsStrict(function);
    /* step 6 */
    FormalParameterList formals = function.getParameters();
    /* step 7 */
    List<Name> parameterNames = BoundNames(formals);
    HashSet<Name> parameterNamesSet = new HashSet<>(parameterNames);
    /* step 8 */
    boolean hasDuplicates = parameterNames.size() != parameterNamesSet.size();
    /* step 9 */
    boolean simpleParameterList = IsSimpleParameterList(formals);
    /* step 10 */
    boolean hasParameterExpressions = ContainsExpression(formals);
    // invariant: hasDuplicates => simpleParameterList
    assert !hasDuplicates || simpleParameterList;
    // invariant: hasParameterExpressions => !simpleParameterList
    assert !hasParameterExpressions || !simpleParameterList;
    /* step 11 */
    Set<Name> varNames = VarDeclaredNames(function);
    /* step 12 */
    List<StatementListItem> varDeclarations = VarScopedDeclarations(function);
    /* step 13 */
    Set<Name> lexicalNames = LexicallyDeclaredNames(function);
    /* step 14 */
    HashSet<Name> functionNames = new HashSet<>();
    /* step 15 */
    ArrayDeque<HoistableDeclaration> functionsToInitialize = new ArrayDeque<>();
    /* step 16 */
    for (StatementListItem item : reverse(varDeclarations)) {
        if (item instanceof HoistableDeclaration) {
            HoistableDeclaration d = (HoistableDeclaration) item;
            Name fn = BoundName(d);
            if (functionNames.add(fn)) {
                functionsToInitialize.addFirst(d);
            }
        }
    }
    if (!functionsToInitialize.isEmpty()) {
        fo = mv.newVariable("fo", FunctionObject.class);
    }
    /* step 17 */
    // Optimization: Skip 'arguments' allocation if it's not referenced within the function.
    boolean argumentsObjectNeeded = function.getScope().needsArguments();
    Name arguments = function.getScope().arguments();
    argumentsObjectNeeded &= arguments != null;
    /* step 18 */
    if (function.getThisMode() == FunctionNode.ThisMode.Lexical) {
        argumentsObjectNeeded = false;
    } else /* step 19 */
    if (parameterNamesSet.contains(arguments)) {
        argumentsObjectNeeded = false;
    } else /* step 20 */
    if (!hasParameterExpressions) {
        if (functionNames.contains(arguments) || lexicalNames.contains(arguments)) {
            argumentsObjectNeeded = false;
        }
    }
    /* step 21 */
    for (Name paramName : function.getScope().parameterNames()) {
        BindingOp<FunctionEnvironmentRecord> op = BindingOp.of(envRec, paramName);
        op.createMutableBinding(envRec, paramName, false, mv);
        if (hasDuplicates) {
            op.initializeBinding(envRec, paramName, undefined, mv);
        }
    }
    /* step 22 */
    if (argumentsObjectNeeded) {
        assert arguments != null;
        Variable<ArgumentsObject> argumentsObj = mv.newVariable("argumentsObj", ArgumentsObject.class);
        if (strict || !simpleParameterList) {
            CreateUnmappedArgumentsObject(mv);
        } else if (formals.getFormals().isEmpty()) {
            CreateMappedArgumentsObject(mv);
        } else {
            CreateMappedArgumentsObject(env, formals, mv);
        }
        mv.store(argumentsObj);
        BindingOp<FunctionEnvironmentRecord> op = BindingOp.of(envRec, arguments);
        if (strict) {
            op.createImmutableBinding(envRec, arguments, false, mv);
        } else {
            op.createMutableBinding(envRec, arguments, false, mv);
        }
        op.initializeBinding(envRec, arguments, argumentsObj, mv);
        parameterNames.add(arguments);
        parameterNamesSet.add(arguments);
    }
    /* steps 24-26 */
    if (hasParameters) {
        if (hasDuplicates) {
            /* step 24 */
            BindingInitialization(codegen, function, env, iterator, mv);
        } else {
            /* step 25 */
            BindingInitialization(codegen, function, env, envRec, iterator, mv);
        }
    }
    /* steps 27-28 */
    HashSet<Name> instantiatedVarNames;
    Variable<? extends LexicalEnvironment<?>> varEnv;
    Variable<? extends DeclarativeEnvironmentRecord> varEnvRec;
    if (!hasParameterExpressions) {
        assert fscope == fscope.variableScope();
        /* step 27.a (note) */
        /* step 27.b */
        instantiatedVarNames = new HashSet<>(parameterNames);
        /* step 27.c */
        for (Name varName : varNames) {
            if (instantiatedVarNames.add(varName)) {
                BindingOp<FunctionEnvironmentRecord> op = BindingOp.of(envRec, varName);
                op.createMutableBinding(envRec, varName, false, mv);
                op.initializeBinding(envRec, varName, undefined, mv);
            }
        }
        /* steps 27.d-27.e */
        varEnv = env;
        varEnvRec = envRec;
    } else {
        assert fscope != fscope.variableScope();
        mv.enterScope(fscope.variableScope());
        /* step 28.a (note) */
        /* step 28.b */
        varEnv = mv.newVariable("varEnv", LexicalEnvironment.class).uncheckedCast();
        newDeclarativeEnvironment(env, mv);
        mv.store(varEnv);
        /* step 28.c */
        varEnvRec = mv.newVariable("varEnvRec", DeclarativeEnvironmentRecord.class);
        getEnvironmentRecord(varEnv, varEnvRec, mv);
        /* step 28.d */
        setVariableEnvironment(varEnv, mv);
        /* step 28.e */
        instantiatedVarNames = new HashSet<>();
        /* step 28.f */
        Variable<Object> tempValue = null;
        for (Name varName : varNames) {
            if (instantiatedVarNames.add(varName)) {
                BindingOp<DeclarativeEnvironmentRecord> op = BindingOp.of(varEnvRec, varName);
                op.createMutableBinding(varEnvRec, varName, false, mv);
                if (!parameterNamesSet.contains(varName) || functionNames.contains(varName)) {
                    op.initializeBinding(varEnvRec, varName, undefined, mv);
                } else {
                    BindingOp.of(envRec, varName).getBindingValue(envRec, varName, strict, mv);
                    if (tempValue == null) {
                        tempValue = mv.newVariable("tempValue", Object.class);
                    }
                    mv.store(tempValue);
                    op.initializeBinding(varEnvRec, varName, tempValue, mv);
                }
            }
        }
    }
    /* step 29 (B.3.3 Block-Level Function Declarations Web Legacy Compatibility Semantics) */
    for (Name fname : function.getScope().blockFunctionNames()) {
        if (instantiatedVarNames.add(fname)) {
            BindingOp<DeclarativeEnvironmentRecord> op = BindingOp.of(varEnvRec, fname);
            op.createMutableBinding(varEnvRec, fname, false, mv);
            op.initializeBinding(varEnvRec, fname, undefined, mv);
        }
    }
    /* steps 30-32 */
    Variable<? extends LexicalEnvironment<?>> lexEnv;
    Variable<? extends DeclarativeEnvironmentRecord> lexEnvRec;
    assert strict || fscope.variableScope() != fscope.lexicalScope();
    if (!strict || fscope.variableScope() != fscope.lexicalScope()) {
        // NB: Scopes are unmodifiable once constructed, that means we need to emit the extra
        // scope for functions with deferred strict-ness, even if this scope is not present in
        // the specification.
        mv.enterScope(fscope.lexicalScope());
        if (!lexicalNames.isEmpty()) {
            /* step 30 */
            lexEnv = mv.newVariable("lexEnv", LexicalEnvironment.class).uncheckedCast();
            newDeclarativeEnvironment(varEnv, mv);
            mv.store(lexEnv);
            /* step 32 */
            lexEnvRec = mv.newVariable("lexEnvRec", DeclarativeEnvironmentRecord.class);
            getEnvironmentRecord(lexEnv, lexEnvRec, mv);
        } else {
            // Optimization: Skip environment allocation if no lexical names are defined.
            /* step 30 */
            lexEnv = varEnv;
            /* step 32 */
            lexEnvRec = varEnvRec;
        }
    } else {
        /* step 30 */
        lexEnv = varEnv;
        /* step 32 */
        lexEnvRec = varEnvRec;
    }
    /* step 33 */
    if (lexEnv != env) {
        setLexicalEnvironment(lexEnv, mv);
    }
    /* step 34 */
    List<Declaration> lexDeclarations = LexicallyScopedDeclarations(function);
    /* step 35 */
    for (Declaration d : lexDeclarations) {
        assert !(d instanceof HoistableDeclaration);
        for (Name dn : BoundNames(d)) {
            BindingOp<DeclarativeEnvironmentRecord> op = BindingOp.of(lexEnvRec, dn);
            if (d.isConstDeclaration()) {
                op.createImmutableBinding(lexEnvRec, dn, true, mv);
            } else {
                op.createMutableBinding(lexEnvRec, dn, false, mv);
            }
        }
    }
    /* step 36 */
    for (HoistableDeclaration f : functionsToInitialize) {
        Name fn = BoundName(f);
        // stack: [] -> [fo]
        InstantiateFunctionObject(context, lexEnv, f, mv);
        mv.store(fo);
        // stack: [fo] -> []
        // Resolve the actual binding name: function(a){ function a(){} }
        // TODO: Can be removed when StaticIdResolution handles this case.
        Name name = fscope.variableScope().resolveName(fn, false);
        BindingOp<DeclarativeEnvironmentRecord> op = BindingOp.of(varEnvRec, name);
        op.setMutableBinding(varEnvRec, name, fo, false, mv);
    }
    /* step 37 */
    mv._return();
}