nodes.cpp

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{
    releaser.release(m_expr1);
    releaser.release(m_expr2);
}

RegisterID* BinaryOpNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    OpcodeID opcodeID = this->opcodeID();
    if (opcodeID == op_neq) {
        if (m_expr1->isNull() || m_expr2->isNull()) {
            RefPtr<RegisterID> src = generator.tempDestination(dst);
            generator.emitNode(src.get(), m_expr1->isNull() ? m_expr2.get() : m_expr1.get());
            return generator.emitUnaryOp(op_neq_null, generator.finalDestination(dst, src.get()), src.get());
        }
    }

    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(m_expr1.get(), m_rightHasAssignments, m_expr2->isPure(generator));
    RegisterID* src2 = generator.emitNode(m_expr2.get());
    return generator.emitBinaryOp(opcodeID, generator.finalDestination(dst, src1.get()), src1.get(), src2, OperandTypes(m_expr1->resultDescriptor(), m_expr2->resultDescriptor()));
}

RegisterID* EqualNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    if (m_expr1->isNull() || m_expr2->isNull()) {
        RefPtr<RegisterID> src = generator.tempDestination(dst);
        generator.emitNode(src.get(), m_expr1->isNull() ? m_expr2.get() : m_expr1.get());
        return generator.emitUnaryOp(op_eq_null, generator.finalDestination(dst, src.get()), src.get());
    }

    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(m_expr1.get(), m_rightHasAssignments, m_expr2->isPure(generator));
    RegisterID* src2 = generator.emitNode(m_expr2.get());
    return generator.emitEqualityOp(op_eq, generator.finalDestination(dst, src1.get()), src1.get(), src2);
}

RegisterID* StrictEqualNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(m_expr1.get(), m_rightHasAssignments, m_expr2->isPure(generator));
    RegisterID* src2 = generator.emitNode(m_expr2.get());
    return generator.emitEqualityOp(op_stricteq, generator.finalDestination(dst, src1.get()), src1.get(), src2);
}

RegisterID* ReverseBinaryOpNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(m_expr1.get(), m_rightHasAssignments, m_expr2->isPure(generator));
    RegisterID* src2 = generator.emitNode(m_expr2.get());
    return generator.emitBinaryOp(opcodeID(), generator.finalDestination(dst, src1.get()), src2, src1.get(), OperandTypes(m_expr2->resultDescriptor(), m_expr1->resultDescriptor()));
}

RegisterID* ThrowableBinaryOpNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(m_expr1.get(), m_rightHasAssignments, m_expr2->isPure(generator));
    RegisterID* src2 = generator.emitNode(m_expr2.get());
    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
    return generator.emitBinaryOp(opcodeID(), generator.finalDestination(dst, src1.get()), src1.get(), src2, OperandTypes(m_expr1->resultDescriptor(), m_expr2->resultDescriptor()));
}

RegisterID* InstanceOfNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    RefPtr<RegisterID> src1 = generator.emitNodeForLeftHandSide(m_expr1.get(), m_rightHasAssignments, m_expr2->isPure(generator));
    RefPtr<RegisterID> src2 = generator.emitNode(m_expr2.get());

    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
    generator.emitGetByIdExceptionInfo(op_instanceof);
    RegisterID* src2Prototype = generator.emitGetById(generator.newTemporary(), src2.get(), generator.globalData()->propertyNames->prototype);

    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
    return generator.emitInstanceOf(generator.finalDestination(dst, src1.get()), src1.get(), src2.get(), src2Prototype);
}

// ------------------------------ LogicalOpNode ----------------------------

LogicalOpNode::~LogicalOpNode()
{
    NodeReleaser::releaseAllNodes(this);
}

void LogicalOpNode::releaseNodes(NodeReleaser& releaser)
{
    releaser.release(m_expr1);
    releaser.release(m_expr2);
}

RegisterID* LogicalOpNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    RefPtr<RegisterID> temp = generator.tempDestination(dst);
    RefPtr<Label> target = generator.newLabel();
    
    generator.emitNode(temp.get(), m_expr1.get());
    if (m_operator == OpLogicalAnd)
        generator.emitJumpIfFalse(temp.get(), target.get());
    else
        generator.emitJumpIfTrue(temp.get(), target.get());
    generator.emitNode(temp.get(), m_expr2.get());
    generator.emitLabel(target.get());

    return generator.moveToDestinationIfNeeded(dst, temp.get());
}

// ------------------------------ ConditionalNode ------------------------------

ConditionalNode::~ConditionalNode()
{
    NodeReleaser::releaseAllNodes(this);
}

void ConditionalNode::releaseNodes(NodeReleaser& releaser)
{
    releaser.release(m_logical);
    releaser.release(m_expr1);
    releaser.release(m_expr2);
}

RegisterID* ConditionalNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    RefPtr<RegisterID> newDst = generator.finalDestination(dst);
    RefPtr<Label> beforeElse = generator.newLabel();
    RefPtr<Label> afterElse = generator.newLabel();

    RegisterID* cond = generator.emitNode(m_logical.get());
    generator.emitJumpIfFalse(cond, beforeElse.get());

    generator.emitNode(newDst.get(), m_expr1.get());
    generator.emitJump(afterElse.get());

    generator.emitLabel(beforeElse.get());
    generator.emitNode(newDst.get(), m_expr2.get());

    generator.emitLabel(afterElse.get());

    return newDst.get();
}

// ------------------------------ ReadModifyResolveNode -----------------------------------

ReadModifyResolveNode::~ReadModifyResolveNode()
{
    NodeReleaser::releaseAllNodes(this);
}

void ReadModifyResolveNode::releaseNodes(NodeReleaser& releaser)
{
    releaser.release(m_right);
}

// FIXME: should this be moved to be a method on BytecodeGenerator?
static ALWAYS_INLINE RegisterID* emitReadModifyAssignment(BytecodeGenerator& generator, RegisterID* dst, RegisterID* src1, RegisterID* src2, Operator oper, OperandTypes types)
{
    OpcodeID opcodeID;
    switch (oper) {
        case OpMultEq:
            opcodeID = op_mul;
            break;
        case OpDivEq:
            opcodeID = op_div;
            break;
        case OpPlusEq:
            opcodeID = op_add;
            break;
        case OpMinusEq:
            opcodeID = op_sub;
            break;
        case OpLShift:
            opcodeID = op_lshift;
            break;
        case OpRShift:
            opcodeID = op_rshift;
            break;
        case OpURShift:
            opcodeID = op_urshift;
            break;
        case OpAndEq:
            opcodeID = op_bitand;
            break;
        case OpXOrEq:
            opcodeID = op_bitxor;
            break;
        case OpOrEq:
            opcodeID = op_bitor;
            break;
        case OpModEq:
            opcodeID = op_mod;
            break;
        default:
            ASSERT_NOT_REACHED();
            return dst;
    }
    
    return generator.emitBinaryOp(opcodeID, dst, src1, src2, types);
}

RegisterID* ReadModifyResolveNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    if (RegisterID* local = generator.registerFor(m_ident)) {
        if (generator.isLocalConstant(m_ident)) {
            RegisterID* src2 = generator.emitNode(m_right.get());
            return emitReadModifyAssignment(generator, generator.finalDestination(dst), local, src2, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
        }
        
        if (generator.leftHandSideNeedsCopy(m_rightHasAssignments, m_right->isPure(generator))) {
            RefPtr<RegisterID> result = generator.newTemporary();
            generator.emitMove(result.get(), local);
            RegisterID* src2 = generator.emitNode(m_right.get());
            emitReadModifyAssignment(generator, result.get(), result.get(), src2, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
            generator.emitMove(local, result.get());
            return generator.moveToDestinationIfNeeded(dst, result.get());
        }
        
        RegisterID* src2 = generator.emitNode(m_right.get());
        RegisterID* result = emitReadModifyAssignment(generator, local, local, src2, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
        return generator.moveToDestinationIfNeeded(dst, result);
    }

    int index = 0;
    size_t depth = 0;
    JSObject* globalObject = 0;
    if (generator.findScopedProperty(m_ident, index, depth, true, globalObject) && index != missingSymbolMarker()) {
        RefPtr<RegisterID> src1 = generator.emitGetScopedVar(generator.tempDestination(dst), depth, index, globalObject);
        RegisterID* src2 = generator.emitNode(m_right.get());
        RegisterID* result = emitReadModifyAssignment(generator, generator.finalDestination(dst, src1.get()), src1.get(), src2, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
        generator.emitPutScopedVar(depth, index, result, globalObject);
        return result;
    }

    RefPtr<RegisterID> src1 = generator.tempDestination(dst);
    generator.emitExpressionInfo(divot() - startOffset() + m_ident.size(), m_ident.size(), 0);
    RefPtr<RegisterID> base = generator.emitResolveWithBase(generator.newTemporary(), src1.get(), m_ident);
    RegisterID* src2 = generator.emitNode(m_right.get());
    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
    RegisterID* result = emitReadModifyAssignment(generator, generator.finalDestination(dst, src1.get()), src1.get(), src2, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
    return generator.emitPutById(base.get(), m_ident, result);
}

// ------------------------------ AssignResolveNode -----------------------------------

AssignResolveNode::~AssignResolveNode()
{
    NodeReleaser::releaseAllNodes(this);
}

void AssignResolveNode::releaseNodes(NodeReleaser& releaser)
{
    releaser.release(m_right);
}

RegisterID* AssignResolveNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    if (RegisterID* local = generator.registerFor(m_ident)) {
        if (generator.isLocalConstant(m_ident))
            return generator.emitNode(dst, m_right.get());
        
        RegisterID* result = generator.emitNode(local, m_right.get());
        return generator.moveToDestinationIfNeeded(dst, result);
    }

    int index = 0;
    size_t depth = 0;
    JSObject* globalObject = 0;
    if (generator.findScopedProperty(m_ident, index, depth, true, globalObject) && index != missingSymbolMarker()) {
        if (dst == generator.ignoredResult())
            dst = 0;
        RegisterID* value = generator.emitNode(dst, m_right.get());
        generator.emitPutScopedVar(depth, index, value, globalObject);
        return value;
    }

    RefPtr<RegisterID> base = generator.emitResolveBase(generator.newTemporary(), m_ident);
    if (dst == generator.ignoredResult())
        dst = 0;
    RegisterID* value = generator.emitNode(dst, m_right.get());
    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
    return generator.emitPutById(base.get(), m_ident, value);
}

// ------------------------------ AssignDotNode -----------------------------------

AssignDotNode::~AssignDotNode()
{
    NodeReleaser::releaseAllNodes(this);
}

void AssignDotNode::releaseNodes(NodeReleaser& releaser)
{
    releaser.release(m_base);
    releaser.release(m_right);
}

RegisterID* AssignDotNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    RefPtr<RegisterID> base = generator.emitNodeForLeftHandSide(m_base.get(), m_rightHasAssignments, m_right->isPure(generator));
    RefPtr<RegisterID> value = generator.destinationForAssignResult(dst);
    RegisterID* result = generator.emitNode(value.get(), m_right.get());
    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
    generator.emitPutById(base.get(), m_ident, result);
    return generator.moveToDestinationIfNeeded(dst, result);
}

// ------------------------------ ReadModifyDotNode -----------------------------------

ReadModifyDotNode::~ReadModifyDotNode()
{
    NodeReleaser::releaseAllNodes(this);
}

void ReadModifyDotNode::releaseNodes(NodeReleaser& releaser)
{
    releaser.release(m_base);
    releaser.release(m_right);
}

RegisterID* ReadModifyDotNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    RefPtr<RegisterID> base = generator.emitNodeForLeftHandSide(m_base.get(), m_rightHasAssignments, m_right->isPure(generator));

    generator.emitExpressionInfo(divot() - m_subexpressionDivotOffset, startOffset() - m_subexpressionDivotOffset, m_subexpressionEndOffset);
    RefPtr<RegisterID> value = generator.emitGetById(generator.tempDestination(dst), base.get(), m_ident);
    RegisterID* change = generator.emitNode(m_right.get());
    RegisterID* updatedValue = emitReadModifyAssignment(generator, generator.finalDestination(dst, value.get()), value.get(), change, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));

    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
    return generator.emitPutById(base.get(), m_ident, updatedValue);
}

// ------------------------------ AssignErrorNode -----------------------------------

AssignErrorNode::~AssignErrorNode()
{
    NodeReleaser::releaseAllNodes(this);
}

void AssignErrorNode::releaseNodes(NodeReleaser& releaser)
{
    releaser.release(m_left);
    releaser.release(m_right);
}

RegisterID* AssignErrorNode::emitBytecode(BytecodeGenerator& generator, RegisterID*)
{
    return emitThrowError(generator, ReferenceError, "Left side of assignment is not a reference.");
}

// ------------------------------ AssignBracketNode -----------------------------------

AssignBracketNode::~AssignBracketNode()
{
    NodeReleaser::releaseAllNodes(this);
}

void AssignBracketNode::releaseNodes(NodeReleaser& releaser)
{
    releaser.release(m_base);
    releaser.release(m_subscript);
    releaser.release(m_right);
}

RegisterID* AssignBracketNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
{
    RefPtr<RegisterID> base = generator.emitNodeForLeftHandSide(m_base.get(), m_subscriptHasAssignments || m_rightHasAssignments, m_subscript->isPure(generator) && m_right->isPure(generator));
    RefPtr<RegisterID> property = generator.emitNodeForLeftHandSide(m_subscript.get(), m_rightHasAssignments, m_right->isPure(generator));
    RefPtr<RegisterID> value = generator.destinationForAssignResult(dst);
    RegisterID* result = generator.emitNode(value.get(), m_right.get());

    generator.emitExpressionInfo(divot(), startOffset(), endOffset());
    generator.emitPutByVal(base.get(), property.get(), result);
    return generator.moveToDestinationIfNeeded(dst, result);
}

// ------------------------------ ReadModifyBracketNode -----------------------------------

ReadModifyBracketNode::~ReadModifyBracketNode()