PLEASE HELP ME

PLEASE HELP ME

[DENIS]

    Please , I do not have any clue in Ada95, but I do have to know how to
determine the order parameters are put on the stack.

    Please write as soons is possible.

             This is my email : datodia@hotmail.com

Re: PLEASE HELP ME

[Tucker Taft]

DENIS (denis23@ix.netcom.com) wrote:

:     Please , I do not have any clue in Ada95, but I do have to know how to
: determine the order parameters are put on the stack.

:     Please write as soons is possible.

This is implementation-dependent.  Perhaps it would be in the
documentation provided by the Ada vendor, in the area of interfacing
with assembly language.  Furthermore, note that these days, not
all parameters are passed on the stack.  For most RISC machines,
at least a few parameters are passed in registers.

You could write your own test case using 'Address which might tell you
something.  E.g.:

  with system.storage_elements; use system.storage_elements;
  with ada.text_io; use ada.text_io;
  procedure stack_order is
    procedure p(A, B, C, D, E, F, G, H, I, J : Integer) is
    begin
      put_line("A'address = " & Integer_Address'Image(To_Integer(A'Address)));
      put_line("B'address = " & Integer_Address'Image(To_Integer(B'Address)));
      put_line("C'address = " & Integer_Address'Image(To_Integer(C'Address)));
      ...
    end p;
  begin
    p(1,2,3,4,5,6,7,8,9,10);
  end stack_order;

:              This is my email : datodia@hotmail.com

--
-Tucker Taft   stt@inmet.com   http://www.inmet.com/~stt/
Intermetrics, Inc.  Burlington, MA  USA
An AverStar Company

Please, help me.

[Adaddict]

I know this questions must seem stupid (I'm sure they really are), but I'm
getting desesperated because I'm not getting those ways of setting the
stack size to work.

Sorry for being a nuisance.

Regards.

Re: Please, help me.

[Jeff Creem]

Adaddict wrote:
> I know this questions must seem stupid (I'm sure they really are), but I'm
> getting desesperated because I'm not getting those ways of setting the
> stack size to work.
> 
> Sorry for being a nuisance.
> 
> Regards.
> 

I've always tried to find ways of avoiding having the main task require 
a large stack. On some OSs, there is no good way to do it at link time 
at all. Is there any way you can restructure your code so you don't need 
a large stack (e.g. If there is a set of large variables within the

procedure blah is
   large variables

begin

end;

then moving all of the large variables to a package spec that the 
procedure blah withs will reduce the stack space.

If it is the sum of lots of littler things through the program then 
perhaps using the storage_size attribute on a new task that does all of 
the real work of the program (with the main thread just terminating) 
will work.

Re: Please, help me.

[Ludovic Brenta]

Jeff Creem <jcreem@yahoo.com> writes:
[...]
> If there is a set of large variables within the
>
> procedure blah is
>    large variables
>
> begin
>
> end;
>
> then moving all of the large variables to a package spec that the
> procedure blah withs will reduce the stack space.
>
> If it is the sum of lots of littler things through the program then
> perhaps using the storage_size attribute on a new task that does all
> of the real work of the program (with the main thread just
> terminating) will work.

I have observed that array or record aggregates tend to be allocated
on the stack, too.  Array aggregates are particularly surprising since
they're easy to replace with loops.  For example:

procedure Proc is
   type T is array (1 .. 100_000) of Integer;
   A : T;
begin
   A := (others => 42); 
end Proc;

allocates two large arrays on the stack (A and the aggregate) with
some compilers I've used.  In contrast:

procedure Proc is
   type T is array (1 .. 100_000) of Integer;
   A : T;
begin
   for J in A'Range loop
      A (J) := 42;
   end loop;
end Proc;

allocates just one array on the stack.

Back on topic, setting the stack size depends on the target operating
system and on the host linker.  There are even situations where it is
not possible to set the stack size at all.

-- 
Ludovic Brenta.