Variable initially assigned in nested scope has declaration misplaced

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What steps will reproduce the problem?
1. Compile attached file: javac -g -cp 
${APARAPI_HOME}/com.amd.aparapi/dist/aparapi.jar Nested.java
2. Execute: java -cp .:${APARAPI_HOME}/com.amd.aparapi/dist/aparapi.jar Nested

This will produce an error message during clBuildProgram of the generated 
OpenCL kernel indicating that i is not declared. The generated kernel will be 
something like:

      int k = 2;
      if (k<3){
         int i = 2;
      } else {
         int i = 4;
      }
      k = i;

because APARAPI misidentifies the scope of i due to its initialization in a 
nested scope. This is primarily caused by the implementation of 
AssignToLocalVariable.isDeclaration() causing the generation of a variable 
declaration only at the point where it is initialized and not earlier as 
needed, as well as misidentifying a point in a program's control flow as 
earlier purely based on bytecode index.

As far as I can tell, this should be independent of platform. 

The hack I put in place to fix this gathers the APARAPI-identified declarations 
in a block, as well as the assignments and searches for variables which are 
declared in one branch of a condition and assigned in another (indicating 
misidentification of the declaration). I do believe a more robust solution will 
be required to handle more general cases where this might occur by calculating 
scope for a local (for instance, I believe Issue 84 is related to this problem).

I've attached a diff to show the changes made to BlockWriter.java

Original issue reported on code.google.com by jmaxg3@gmail.com on 11 Jan 2013 at 3:38

Attachments:

• Nested.java
• diff.out