Subject: working group 3

From: Marina Chen <[email-masked]>
Date: Fri, 20 Mar 92 14:40:48 EST

Dear Members of Working Group 3,

Below is the list of issues raised at our group meeting.  If you
have additional items you want to add, please send them to me.
I'd also like to collect examples that help to illustrate these
issues.  If you feel strongly about how we should do certain
things certain way, please use one or more examples to
illustrate your approach.

Please send the examples directly to me by April 6 if possible.
I'll organize them into groups and broadcast to everyone.
Hope that can get us started.

--Marina Chen

==================================================================

Issues of Working Group 3:

(1) SUBROUTINE INTERFACES

  * array sections 

  * automatic distribution upon entry and exit,
  specification/conversion by caller or callee

  * (sequence association)

  * inheritance of distribution

  * distribution of local array variables w.r.t. formal arguments

(2) SCOPE OF DIRECTIVES

  * lexical -- block structured

  * subroutine boundary

  * executable statements

  * For those arrays that are aligned, what happens when
  the computation goes across the (procedure or block) boundary ?

(3) CLASSES OF DISTRIBUTION FUNCTIONS

  * parameterized (e.g. if P > 16 then D1 else D2)  where 
    P is the num. of procs. and D1 and D2 are distributions

  * data-dependent distribution 

  (4) DIRECTIVES SHOULD BE SEMANTIC-PRESERVING 

  * e.g. sequential, shared-memory, distributed-memory
    implementations all have the same behavior.
    In what way the directives can be safely ignored?

  * automatic distribution upon entry/exit

(5) IS DISTRIBUTION QUERY NECESSARY?

  * restriction on redistribution: returned value can only be other directives.

  * Is this enough 

  * effect on block structure

(6) IMPACT ON LIBRARY