Subject: Re: hpff-task: extension to the on-clause and alternative for task regions

From: [email-masked]
Date: Tue, 19 Sep 95 00:15:38 EDT

---------------------------------------------------------------------------
[email-masked] is a mailing list for discussion of control-parallel
features in HPF.  Instructions for adding or deleting yourself from this
list appear at the bottom of this message.
---------------------------------------------------------------------------

(Response to Piyush's proposal about using  LOCAL with ON to
achieve task parallelism, thus eliminating the need for
TASK REGION..END TASK REGION syntax)

Piyush,

  ON clauses with LOCAL would make it possible to write a class
  of task parallel programs. The tradeoffs with using a task
  region are:

  1. As you pointed out, there is no reasonable way to access
     global/common variables from tasks. At the previous HPF
     meetings, several people conveyed that the code in tasks should
     be general and should allow access to common blocks. 

  2. I am not sure how I/O constraints can be specified in this model
     (short of something  ugly like specifying unit numbers as LOCAL
     to an ON region). In the task region model (and in INDEPENDENT
     loops) I/O constraints can be specified relatively since a
     relevant code section is defined. Without a task region, the entire
     program has to be considered.

jaspal
  
---------------------------------------------------------------------------
To (un)subscribe to this list, send mail to [email-masked].
Leave the subject line blank, and in the body put the line
(un)subscribe <email-address>
---------------------------------------------------------------------------