MY_COMPILER/midend/llvm/use/IrUser.java

package midend.llvm.use;

import java.util.ArrayList;

import midend.llvm.value.IrValue;
import midend.llvm.type.IrType;

public class IrUser extends IrValue {
    private ArrayList<IrValue> uses;

    public IrUser(IrType type, String name) {
        super(type, name);
        this.uses = new ArrayList<>();
    }

    public ArrayList<IrValue> getUses() {
        return uses;
    }

    public void addUse(IrValue value) {
        uses.add(value);
        if (value != null) {
            value.addUser(this);
        }
    }

    public IrValue getUse(int index) {
        if (index >= uses.size()) {
            return null;
        }
        return uses.get(index);
    }

    public void setUse(int index, IrValue value) {
        if (index >= uses.size() || index < 0) {
            return;
        }
        IrValue oldValue = uses.get(index);
        if (oldValue != null) {
            oldValue.deleteUser(this);
        }
        uses.set(index, value);
        if (value != null) {
            value.addUser(this);
        }
    }

    public void deleteUse(IrValue value) {
        uses.remove(value);
        if (value != null) {
            value.deleteUser(this);
        }   
    }

    public void clearUses() {
        for (IrValue value : uses) {
            if (value != null) {
                value.deleteUser(this);
            }
        }
        uses.clear();
    }

    public void deleteUse(int index) {
        if (index >= uses.size() || index < 0) {
            return;
        }
        IrValue value = uses.get(index);
        deleteUse(value);
    }

    public int getNumUses() {
        return uses.size();
    }
}