[Soot-list] Jasmin annotation bug(fix)

[Christophe Foket]

Hello,

I am trying to run Soot on the tradebeans benchmark, which is part of 
the latest dacapo release. For this, I am using the methodology 
described here: http://www.bodden.de/2010/03/29/soot-tamiflex-dacapo/. 
One of the dumped classes is "javax.persistence.OneToMany". This class 
is read in correctly by soot, but written out incorrectly even if no 
transformations are applied to it.

The problem with this class is that there are two extra bytes inserted 
in the annotation of one of its methods. Below is the output of "javap 
-verbose javax.persistence.OneToMany" for both the original class and 
the (untransformed) class generated by soot.

Original:
=====

public abstract javax.persistence.CascadeType[] cascade();
     Signature: ()[Ljavax/persistence/CascadeType;
     AnnotationDefault: length = 0x3
      5B 00 00

Sootified:
======

public abstract javax.persistence.CascadeType[] cascade();
     Signature: ()[Ljavax/persistence/CascadeType;
     AnnotationDefault: length = 0x5
     00 17 5B 00 00

Note that the 5B 00 00, corresponds to an array (5B is '[') of size 
zero, which is what we expect. The "00 17", on the other hand points to 
an entry in the constant pool, representing the name of the array 
annotation, which is "default". After some debugging, I found out that 
the annotation is internally represented by an ArrayElemValPair. 
ArrayElemValPair extends ElemValPair, which defines a method setNoName() 
that, when called makes sure that the constant pool index of the 
ElemValPair's name is not written out. The problem, however, is in 
ArrayElemValPair, which overrides setNoName(), without performing a 
super call:

     public void setNoName(){
         if (list == null) return;
         Iterator it = list.iterator();
         while (it.hasNext()){
             ((ElemValPair)it.next()).setNoName();
         }
     }

In this case, the setNoName() method is called on all elements of the 
list, but not on the annotation itself. Therefore, whenever the 
annotation is written out, it ithe constant pool index of its name is 
also written out. Changing the implementation of setNoName() to

     public void setNoName(){
*super.setNoName();*
         if (list == null) return;
         Iterator it = list.iterator();
         while (it.hasNext()){
             ((ElemValPair)it.next()).setNoName();
         }
     }

causes Soot to generate the class file correctly.

I don't know enough about the internals of jasmin to decide whether or 
not this fixes the issue entirely, but it at least seemed to solve my 
problem.

Best,

Christophe
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