Resend: Retiring Returner

[Jonathan S. Shapiro]

Sorry about the last post -- it was keyed from my palm pilot, and
apparently I had line wrap misconfigured in my desktop mail agent.
Here is the same message, properly wrapped:

I'm considering retiring the returner.

Key permutation can be done significantly faster as an indivisible
supervisor-implememted instruction. I need key load/store instructions
to support capability pages anyway - adding key reg copy/swap
instructions is not a signifiiant addition. I can see no reason why
the authority to do these operations should not be intrinsic to a
process.

String permutation (CALL case) is better handled with a library
routine.

Prompt RETURN/SEND are more efficiently implemented with a mode bit on
the operation. Is there any argument that such prompt operations
should require explicit authority?

Jonathan S. Shapiro
http://www.cis.upenn.edu/~shap

The EROS operating system:
http://www.cis.upenn.edu/~eros