I would like to refactor and improve the test /oracle-work/jdk-fork6/open/test/hotspot/jtreg/compiler/loopopts/superword/TestDependencyOffsets.java

It currently is generated with a python script, and should instead use the new CompileFramework.

It would allow us to perform some additional random checks, and allows us to have the code-gen all in Java.

I will also need to change some IR rules soon because of JDK-8334431, and so this refactor would come in handy for that too.