Getting started with GNU Assembler

[Jyoti Rajendra Allur]

Hi All,
I am interested in understanding and contributing to AS of binutils. 
Any documentation, tutorials/ links that would help get started would be highly appreciated.
I have already downloaded binutils 2.25 and have cross compiled it for arm. 
I would like to delve into the code now.

How so I set it up for debugging and what are all the test suites to be run for sanity checking before submit the patch?

Regards,
Jyoti Allur