Subject: hpff-interpret: remapping of arguments inside independent

From: Larry Meadows <[email-masked]>
Date: Sat, 7 Oct 1995 18:55:03 GMT

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In Section 4.4 of the standard, one of the conditions on INDEPENDENT is
that realignment and redistribution cannot occur, since they may change
the processor storing a particular array element.

I would argue that the same reasoning applies to remapping of arguments
in subroutines called inside of INDEPENDENT DO loops. For example:

!hpf$ distribute a(block)
!hpf$ indepedent
	do i = 1,n
	    call sub(a)
	enddo

	subroutine sub(a)
	real a(:)
!hpf$ distribute a(cyclic)
	...
	return
	end

>From an implementation point of view, remapping of arguments is a
collective operation, just as is realignment or redistribution, so
is difficult to implement inside INDEPENDENT DO loops.

Couple of other points:

- Would be nice to have some examples in 4.4.1 where subroutines were
  called, legally and illegally.

- I seem to recall that we decided that local variables of subroutines
  called inside INDEPENDENT DO loops were automatically NEW (and I
  assume that this doesn't apply to SAVE or COMMON variables). Is this
  documented anywhere?

Thanks.

lfm
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