M0 design problem

[Brian Gernhardt]

On Apr 1, 2012, at 11:17 PM, Jimmy Zhuo wrote:

> I just realized that M0 is stack based. M0 is dedicated to use the least op to do the work, it's extreme makes it being stack based, not register based. If the latter is more advanced, then it's a retrogression. Here is some compares:
> 
> M0:
> set_imm I0, 0, 123
> set_imm I1, 0, 356
> add_i     I2, I1, I0

> CPU-ish:
> mov %eax, 123
> add %eax, 356
> or
> add %eax, %ebx
> or
> add %eax, [0]   # [0] is memory unit.
> or
> add [0], %eax   # [0] is memory unit.
> 
> In M0, we can't do this:
> add_i I2, 123, 356

I have thought it would be nice if M0 had some concept of addressing modes.  Indirect, indexed, and immediate are things that jump to mind quickly.  They could be handled by the core runloop before dispatching off to the ops for simplicity.

~~ Benabik