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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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package com.oracle.truffle.js.nodes.access;

import java.util.ArrayList;
import java.util.List;
import java.util.Set;

import com.oracle.truffle.api.CompilerDirectives;
import com.oracle.truffle.api.frame.Frame;
import com.oracle.truffle.api.frame.FrameDescriptor;
import com.oracle.truffle.api.frame.FrameSlot;
import com.oracle.truffle.api.frame.FrameUtil;
import com.oracle.truffle.api.frame.VirtualFrame;
import com.oracle.truffle.api.instrumentation.Tag;
import com.oracle.truffle.api.nodes.NodeCost;
import com.oracle.truffle.api.nodes.NodeInfo;
import com.oracle.truffle.js.nodes.JavaScriptNode;
import com.oracle.truffle.js.runtime.JSArguments;
import com.oracle.truffle.js.runtime.JSFrameUtil;

public abstract class LazyWriteFrameSlotNode extends JavaScriptNode implements WriteNode {
    protected final Object identifier;
    @Child protected JavaScriptNode rhs;

    public LazyWriteFrameSlotNode(Object identifier, JavaScriptNode rhs) {
        this.identifier = identifier;
        this.rhs = rhs;
    }

    public Object getIdentifier() {
        return identifier;
    }

    public static LazyWriteFrameSlotNode create(Object identifier, JavaScriptNode rhs) {
        return new LazyWriteFrameSlotUninitNode(identifier, rhs);
    }

    @Override
    public JavaScriptNode getRhs() {
        return rhs;
    }

    @Override
    public final Object execute(VirtualFrame frame) {
        return executeWrite(frame, rhs.execute(frame));
    }

    @NodeInfo(cost = NodeCost.UNINITIALIZED)
    private static final class LazyWriteFrameSlotUninitNode extends LazyWriteFrameSlotNode {
        LazyWriteFrameSlotUninitNode(Object identifier, JavaScriptNode rhs) {
            super(identifier, rhs);
        }

        @Override
        public Object executeWrite(VirtualFrame frame, Object value) {
            CompilerDirectives.transferToInterpreterAndInvalidate();

            Frame outerFrame = frame;
            for (int frameLevel = 0;; frameLevel++) {
                Frame outerScope = outerFrame;
                List<FrameSlot> parentSlotList = new ArrayList<>();
                for (int scopeLevel = 0;; scopeLevel++) {
                    FrameDescriptor outerFrameDescriptor = outerScope.getFrameDescriptor();
                    FrameSlot slot = outerFrameDescriptor.findFrameSlot(identifier);
                    if (slot != null) {
                        FrameSlot[] parentSlots = parentSlotList.toArray(ScopeFrameNode.EMPTY_FRAME_SLOT_ARRAY);
                        ScopeFrameNode scopeFrameNode = ScopeFrameNode.create(frameLevel, scopeLevel, parentSlots);
                        JSWriteFrameSlotNode resolved = JSWriteFrameSlotNode.create(slot, scopeFrameNode, rhs, outerFrameDescriptor, JSFrameUtil.hasTemporalDeadZone(slot));
                        return this.replace(resolved).executeWrite(frame, value);
                    }

                    FrameSlot parentSlot = outerFrameDescriptor.findFrameSlot(ScopeFrameNode.PARENT_SCOPE_IDENTIFIER);
                    if (parentSlot == null) {
                        break;
                    }
                    outerScope = (Frame) FrameUtil.getObjectSafe(outerScope, parentSlot);
                    parentSlotList.add(parentSlot);
                }

                outerFrame = JSArguments.getEnclosingFrame(outerFrame.getArguments());
                if (outerFrame == JSFrameUtil.NULL_MATERIALIZED_FRAME) {
                    break;
                }
            }

            throw new RuntimeException("frame slot not found");
        }

        @Override
        protected JavaScriptNode copyUninitialized(Set<Class<? extends Tag>> materializedTags) {
            return new LazyWriteFrameSlotUninitNode(identifier, cloneUninitialized(rhs, materializedTags));
        }
    }
}