Re: Coroutines and Go

[David Kastrup <dak@...>]

Paul Hudson <phudson@pobox.com> writes:

> (Sorry about the repeated messages)
>
>
>     They were definitely not new in 1979 (Motorola's 6809 supported them) but
>     keeping stuff in the stack was not uncommon even with the 6502, even
>     without direct hardware support.
>
>
> Way before that - the PDP-11 has hardware support for a stack, and I'll bet it
> wasn't the first.

But we are not talking about the availability of index register based
addressing.  We are talking about it being equally efficient.

Old architectures not even had a return stack.

<URL:http://www.cs.uiowa.edu/~jones/cdc160/man/jump.html#func>

Later optimized with an explicit return jump instruction which did the
same non-reentrable hackery.

-- 
David Kastrup