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dataflow-shaded is a dataflow framework based on the javac compiler. It differs from the org.checkerframework:dataflow artifact in two ways. First, the packages in this artifact have been renamed to org.checkerframework.shaded.*. Second, unlike the dataflow artifact, this artifact contains the dependencies it requires.

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package org.checkerframework.dataflow.livevariable;

import java.util.List;
import org.checkerframework.dataflow.analysis.BackwardTransferFunction;
import org.checkerframework.dataflow.analysis.RegularTransferResult;
import org.checkerframework.dataflow.analysis.TransferInput;
import org.checkerframework.dataflow.analysis.TransferResult;
import org.checkerframework.dataflow.analysis.UnusedAbstractValue;
import org.checkerframework.dataflow.cfg.UnderlyingAST;
import org.checkerframework.dataflow.cfg.node.AbstractNodeVisitor;
import org.checkerframework.dataflow.cfg.node.AssignmentNode;
import org.checkerframework.dataflow.cfg.node.MethodInvocationNode;
import org.checkerframework.dataflow.cfg.node.Node;
import org.checkerframework.dataflow.cfg.node.ObjectCreationNode;
import org.checkerframework.dataflow.cfg.node.ReturnNode;
import org.checkerframework.dataflow.qual.SideEffectFree;

/** A live variable transfer function. */
public class LiveVarTransfer
    extends AbstractNodeVisitor<
        TransferResult,
        TransferInput>
    implements BackwardTransferFunction {

  /** Creates a new LiveVarTransfer. */
  public LiveVarTransfer() {}

  @Override
  @SideEffectFree
  public LiveVarStore initialNormalExitStore(
      UnderlyingAST underlyingAST, List returnNodes) {
    return new LiveVarStore();
  }

  @Override
  public LiveVarStore initialExceptionalExitStore(UnderlyingAST underlyingAST) {
    return new LiveVarStore();
  }

  @Override
  public RegularTransferResult visitNode(
      Node n, TransferInput p) {
    return new RegularTransferResult<>(null, p.getRegularStore());
  }

  @Override
  public RegularTransferResult visitAssignment(
      AssignmentNode n, TransferInput p) {
    RegularTransferResult transferResult =
        (RegularTransferResult) super.visitAssignment(n, p);
    processLiveVarInAssignment(n.getTarget(), n.getExpression(), transferResult.getRegularStore());
    return transferResult;
  }

  @Override
  public RegularTransferResult visitMethodInvocation(
      MethodInvocationNode n, TransferInput p) {
    RegularTransferResult transferResult =
        (RegularTransferResult)
            super.visitMethodInvocation(n, p);
    LiveVarStore store = transferResult.getRegularStore();
    for (Node arg : n.getArguments()) {
      store.addUseInExpression(arg);
    }
    return transferResult;
  }

  @Override
  public RegularTransferResult visitObjectCreation(
      ObjectCreationNode n, TransferInput p) {
    RegularTransferResult transferResult =
        (RegularTransferResult) super.visitObjectCreation(n, p);
    LiveVarStore store = transferResult.getRegularStore();
    for (Node arg : n.getArguments()) {
      store.addUseInExpression(arg);
    }
    return transferResult;
  }

  @Override
  public RegularTransferResult visitReturn(
      ReturnNode n, TransferInput p) {
    RegularTransferResult transferResult =
        (RegularTransferResult) super.visitReturn(n, p);
    Node result = n.getResult();
    if (result != null) {
      LiveVarStore store = transferResult.getRegularStore();
      store.addUseInExpression(result);
    }
    return transferResult;
  }

  /**
   * Update the information of live variables from an assignment statement.
   *
   * @param variable the variable that should be killed
   * @param expression the expression in which the variables should be added
   * @param store the live variable store
   */
  private void processLiveVarInAssignment(Node variable, Node expression, LiveVarStore store) {
    store.killLiveVar(new LiveVarNode(variable));
    store.addUseInExpression(expression);
  }
}