FIFO Optimization status 2

[Zhao Shuai]

In the last two weeks I worked on rewriting the FIFO system using pipe
routines. Now the work is accomplished. Any comments or feedback is
welcome.

I have write several testing programs to test the new FIFO system and
the result shows that it works well. I also put attention to the
previously reported FIFO bugs and am happy to see that a well known
FIFO bug(see PR 76525, 76144, 94772, etc) is eliminated.

You can find these testing programs in my perforce branch:
//depot/projects/soc2009/fifo/fifo_test/functionality/...

More tests will be added next week.


-- 
Regards,
Zhao