RE: [avr-gcc-list] Any SimulAVR or avrtest users out there?

[John Regehr]

> For the sake of discussion here, what makes it very easy to extend?

Avrora makes it easy to write "monitors" which are Java classes that can 
receive callbacks when many interesting kinds of simulator events occur: 
memory operations, instruction execution, interrupts, etc.  A majority of 
the little simulator hacks that we end up needing turn out to be 
conveniently expressible as monitors.  You can drop in a monitor without 
even recompiling the simulator.  There are other things I'm leaving out, 
but the monitor interface is the main thing I used.

A few random monitors I wrote or hacked on were:

- a simple printf, triggered by a store to a magic memory location
- terminate simulator on a "break" instruction
- keep track of maximum stack depth
- take timing measurements between specified starting and stopping
  addresses
- profiling the kinds of values stored in regions of RAM

There are a bunch more.  Obviously you can hack this kind of functionality 
into any simulator, but here it is easy and convenient and you don't 
clutter up the simulator core.

John