Class BusyCodeMotion

  extended by soot.Transformer
      extended by soot.BodyTransformer
          extended by soot.jimple.toolkits.scalar.pre.BusyCodeMotion

public class BusyCodeMotion
extends BodyTransformer

Performs a partial redundancy elimination (= code motion). This is done, by moving everycomputation as high as possible (it is easy to show, that they are computationally optimal), and then replacing the original computation by a reference to this new high computation. This implies, that we introduce many new helper-variables (that can easily be eliminated afterwards).
In order to catch every redundant expression, this transformation must be done on a graph without critical edges. Therefore the first thing we do, is removing them. A subsequent pass can then easily remove the synthetic nodes we have introduced.
The term "busy" refers to the fact, that we always move computations as high as possible. Even, if this is not necessary.

See Also:

Constructor Summary
BusyCodeMotion(Singletons.Global g)
Method Summary
protected  void internalTransform(Body b, String phaseName, Map opts)
          performs the busy code motion.
static BusyCodeMotion v()
Methods inherited from class soot.BodyTransformer
transform, transform, transform
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail


public BusyCodeMotion(Singletons.Global g)
Method Detail


public static BusyCodeMotion v()


protected void internalTransform(Body b,
                                 String phaseName,
                                 Map opts)
performs the busy code motion.

Specified by:
internalTransform in class BodyTransformer
b - the body on which to apply the transformation
phaseName - the phasename for this transform; not typically used by implementations.
opts - the actual computed options; a combination of default options and Scene specified options.