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 * (a) the Software, and
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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
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 * Software and the Larger Work(s), and to sublicense the foregoing rights on
 * either these or other terms.
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 * This license is subject to the following condition:
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package com.oracle.truffle.sl.nodes.call;

import com.oracle.truffle.api.CompilerAsserts;
import com.oracle.truffle.api.dsl.NodeChild;
import com.oracle.truffle.api.dsl.NodeChildren;
import com.oracle.truffle.api.dsl.Specialization;
import com.oracle.truffle.api.frame.VirtualFrame;
import com.oracle.truffle.api.interop.ForeignAccess;
import com.oracle.truffle.api.interop.Message;
import com.oracle.truffle.api.interop.TruffleObject;
import com.oracle.truffle.api.nodes.ExplodeLoop;
import com.oracle.truffle.api.nodes.Node;
import com.oracle.truffle.api.nodes.NodeInfo;
import com.oracle.truffle.api.source.SourceSection;
import com.oracle.truffle.sl.nodes.SLExpressionNode;
import com.oracle.truffle.sl.runtime.SLContext;
import com.oracle.truffle.sl.runtime.SLFunction;

/**
 * The node for function invocation in SL. Since SL has first class functions, the
 * {@link SLFunction target function} can be computed by an arbitrary expression. This node is
 * responsible for evaluating this expression, as well as evaluating the {@link #argumentNodes
 * arguments}. The actual dispatch is then delegated to a chain of {@link SLDispatchNode} that form
 * a polymorphic inline cache.
 */
@NodeInfo(shortName = "invoke")
@NodeChildren({@NodeChild(value = "functionNode", type = SLExpressionNode.class)})
public abstract class SLInvokeNode extends SLExpressionNode {
    @Children private final SLExpressionNode[] argumentNodes;
    @Child private SLDispatchNode dispatchNode;

    SLInvokeNode(SourceSection src, SLExpressionNode[] argumentNodes) {
        super(src);
        this.argumentNodes = argumentNodes;
        this.dispatchNode = SLDispatchNodeGen.create();
    }

    @Specialization
    @ExplodeLoop
    public Object executeGeneric(VirtualFrame frame, SLFunction function) {
        /*
         * The number of arguments is constant for one invoke node. During compilation, the loop is
         * unrolled and the execute methods of all arguments are inlined. This is triggered by the
         * ExplodeLoop annotation on the method. The compiler assertion below illustrates that the
         * array length is really constant.
         */
        CompilerAsserts.compilationConstant(argumentNodes.length);

        Object[] argumentValues = new Object[argumentNodes.length];
        for (int i = 0; i < argumentNodes.length; i++) {
            argumentValues[i] = argumentNodes[i].executeGeneric(frame);
        }
        return dispatchNode.executeDispatch(frame, function, argumentValues);
    }

    @Child private Node crossLanguageCall;

    @Specialization
    @ExplodeLoop
    protected Object executeGeneric(VirtualFrame frame, TruffleObject function) {
        /*
         * The number of arguments is constant for one invoke node. During compilation, the loop is
         * unrolled and the execute methods of all arguments are inlined. This is triggered by the
         * ExplodeLoop annotation on the method. The compiler assertion below illustrates that the
         * array length is really constant.
         */
        CompilerAsserts.compilationConstant(argumentNodes.length);

        Object[] argumentValues = new Object[argumentNodes.length];
        for (int i = 0; i < argumentNodes.length; i++) {
            argumentValues[i] = argumentNodes[i].executeGeneric(frame);
        }
        if (crossLanguageCall == null) {
            crossLanguageCall = insert(Message.createExecute(argumentValues.length).createNode());
        }
        Object res = ForeignAccess.execute(crossLanguageCall, frame, function, argumentValues);
        return SLContext.fromForeignValue(res);
    }
}