Writing a new simulator

[David Golombek <daveg at maker dot com>]

I'm examining using the simulator code packaged with GDB for the basis
of a new simulator project.  I haven't seen much discussion here about
the simulator packages, but haven't seen any other lists that might be
appropriate.  If there is another list, please direct me towards it.
I've read through a fair bit of the existing code, and wanted to ask
some questions to make sure my assumptions are correct.

This work is for a new processor, to which I've already ported the
Binutils, GDB, and Gas.  This is for a 32bit processor with a lot of
special functional units, which are memory mapped.

1) It seems that using either the mips or the v850 code as an example
it the best bet, using the same igen framework that they use.  T/F?

2) Reading the igen source, as well as the code in 'common', is the
only existing documentation on igen.  T/F?

3) Is there a good "ramp-up" methodology for writing a simulator, or
do I need to write very large parts of it before its useful at all?
IE, are there some pieces that I can implement first to get at least a
simulator that will run, if not do anything, so that I can do
piecewise implementation?

4) Are there any mail archives or any discussion saved anywhere of the
previous simulator implementations?  Just to give me a heads up on
potential pit-falls, etc., that i may run into. 

Thanks in advance for any suggestions or pointers,
DaveG