Re: Query about monitor (passive) task optimization

[pipex!sunic!celsiustech.se!bjkae@uunet.uu.net (Bjorn Kallberg)]

In article <CB403J.74M@ddciiny.UUCP> jls@ddciiny.UUCP (Jonathan
Schilling) writes:

>I've heard of these objections before, but I don't fully understand them. 
>Assuming the optimization is transparent to the programmer, and does not 
>in any way change the semantics of the program, what "control" is being
>lost?  

I thought a Real Time program was a program, where timing was an essential
part of the semantics. Thus, semantics is changed.

>From within the program, using only standard Ada, one wouldn't
>even be able to detect whether the optimization had happened or not 
>(this might be doable with CIFO-type interfaces, depending on the
>runtime system implementation).  The only difference is that the program
>runs faster.

Or suddenly slower, when you change the program in some little way, so
the compiler can not apply the optimization any longer, that it previously did.
And you do not get a warning or error, which you will if you have explicitly
told the compiler, that this must be a passive task.

By the way, are not the automatic type conversions made by some programming
languages, like PL1, quite wonderful? You don't have to write a lot of
silly and unneccesary stuff. 

>
>-- 
>Jonathan Schilling
>DDC-I, Inc.
>uunet!ddciiny!jls

Bj|rn K{llberg
bjkae@celsiustech.se