Examples with BreakLabel com.github.anba.es6draft.compiler.Labels.BreakLabel used on opensource projects

Example 6 with BreakLabel

use of com.github.anba.es6draft.compiler.Labels.BreakLabel in project es6draft by anba.

the class StatementGenerator method ForInOfBodyEvaluation.

/**
     * 13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation (lhs, stmt, iterator, lhsKind, labelSet)
     * <p>
     * stack: [Iterator] {@literal ->} []
     * 
     * @param <FORSTATEMENT>
     *            the for-statement node type
     * @param node
     *            the for-statement node
     * @param mv
     *            the code visitor
     * @return the completion value
     */
private <FORSTATEMENT extends IterationStatement & ForIterationNode> Completion ForInOfBodyEvaluation(FORSTATEMENT node, CodeVisitor mv) {
    assert mv.getStackSize() == 1;
    ContinueLabel lblContinue = new ContinueLabel();
    BreakLabel lblBreak = new BreakLabel();
    Jump enter = new Jump(), test = new Jump();
    mv.enterVariableScope();
    Variable<ScriptIterator<?>> iterator = mv.newVariable("iter", ScriptIterator.class).uncheckedCast();
    // stack: [Iterator] -> []
    mv.store(iterator);
    Variable<Object> nextValue = mv.newVariable("nextValue", Object.class);
    Variable<LexicalEnvironment<?>> savedEnv = saveEnvironment(node, mv);
    /* step 2 */
    if (node.hasCompletionValue()) {
        mv.storeUndefinedAsCompletionValue();
    }
    /* steps 3-4 (not applicable) */
    /* step 5 (repeat loop) */
    mv.nonDestructiveGoTo(test);
    /* steps 5.d-e */
    mv.mark(enter);
    mv.load(iterator);
    mv.lineInfo(node);
    mv.invoke(Methods.Iterator_next);
    mv.store(nextValue);
    /* steps 5.f-l */
    {
        mv.enterIteration(node, lblBreak, lblContinue);
        mv.enterWrapped();
        new IterationGenerator<FORSTATEMENT>(codegen) {

            @Override
            protected Completion iterationBody(FORSTATEMENT node, Variable<ScriptIterator<?>> iterator, CodeVisitor mv) {
                return ForInOfBodyEvaluationInner(node, nextValue, mv);
            }

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

            @Override
            protected List<TempLabel> exitIteration(FORSTATEMENT node, CodeVisitor mv) {
                return mv.exitIterationBody(node);
            }
        }.generate(node, iterator, test, mv);
        mv.exitWrapped();
        mv.exitIteration(node);
    }
    /* steps 5.m-n */
    if (lblContinue.isTarget()) {
        mv.mark(lblContinue);
        restoreEnvironment(savedEnv, mv);
    }
    /* steps 5.a-c */
    mv.mark(test);
    mv.load(iterator);
    mv.lineInfo(node);
    mv.invoke(Methods.Iterator_hasNext);
    mv.ifne(enter);
    /* steps 5.m-n */
    if (lblBreak.isTarget()) {
        mv.mark(lblBreak);
        restoreEnvironment(savedEnv, mv);
    }
    mv.exitVariableScope();
    return Completion.Normal;
}

Example 7 with BreakLabel

use of com.github.anba.es6draft.compiler.Labels.BreakLabel in project es6draft by anba.

the class StatementGenerator method ForBodyEvaluation.

/**
     * 13.7.4.8 Runtime Semantics: ForBodyEvaluation(test, increment, stmt, perIterationBindings,
     * labelSet)
     */
private Completion ForBodyEvaluation(ForStatement node, boolean perIterationsLets, CodeVisitor mv) {
    assert mv.getStackSize() == 0;
    mv.enterVariableScope();
    /* step 1 */
    if (node.hasCompletionValue()) {
        mv.storeUndefinedAsCompletionValue();
    }
    /* steps 2-3 */
    Variable<LexicalEnvironment<?>> savedEnv;
    if (perIterationsLets) {
        savedEnv = mv.newVariable("savedEnv", LexicalEnvironment.class).uncheckedCast();
        CreatePerIterationEnvironment(savedEnv, mv);
    } else {
        savedEnv = saveEnvironment(node, mv);
    }
    Jump lblTest = new Jump(), lblStmt = new Jump();
    ContinueLabel lblContinue = new ContinueLabel();
    BreakLabel lblBreak = new BreakLabel();
    Bool btest = node.getTest() != null ? Bool.evaluate(node.getTest()) : Bool.True;
    /* steps 4.b-d */
    Completion result;
    if (btest != Bool.True) {
        mv.nonDestructiveGoTo(lblTest);
    }
    mv.mark(lblStmt);
    {
        mv.enterIteration(node, lblBreak, lblContinue);
        result = node.getStatement().accept(this, mv);
        mv.exitIteration(node);
    }
    /* step 4.c (abrupt completion - continue) */
    if (lblContinue.isTarget()) {
        mv.mark(lblContinue);
        restoreEnvironment(savedEnv, mv);
    }
    /* steps 4.e-f */
    if (perIterationsLets && (!result.isAbrupt() || lblContinue.isTarget())) {
        CreatePerIterationEnvironment(savedEnv, mv);
    }
    /* step 4.g */
    if (node.getStep() != null && (!result.isAbrupt() || lblContinue.isTarget())) {
        ValType type = expression(node.getStep().emptyCompletion(), mv);
        mv.pop(type);
    }
    /* step 4.a */
    if (btest != Bool.True) {
        mv.mark(lblTest);
        ValType type = expression(node.getTest(), mv);
        ToBoolean(type, mv);
        mv.ifne(lblStmt);
    } else {
        mv.goTo(lblStmt);
    }
    /* step 4.c (abrupt completion - break) */
    if (lblBreak.isTarget()) {
        mv.mark(lblBreak);
        restoreEnvironment(savedEnv, mv);
    }
    mv.exitVariableScope();
    if (btest == Bool.True) {
        if (!result.isAbrupt() && !lblBreak.isTarget()) {
            // infinite loop
            return Completion.Abrupt;
        }
        return result.normal(lblBreak.isTarget());
    }
    return Completion.Normal;
}