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Re: Creating a new stack from an exisiting one.

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"Chad" <cdalten@gmail.com> wrote in message 
news:b227ba50-ccbc-4da0-9f6a-31bb809f329d@ah9g2000pbd.googlegroups.com...

> That what I thought. However, I don't think so. Let me elaborate. This
> is part of a much much larger software project. The part is question
> is the RunTimeStack module. In this module, we have one stack which is
> called runStack. This is an ArrayList that is supposed to hold the
> data pushed onto the stack. In other words, after I push the numbers
> onto the stack, it would look something like..
>
> [1, 4, 10, 20]
>
> There is another stack, of type Stack, that is called framePointers.
> This holds the current offset.

So this is some sort of language where you can have a stack of frame 
pointers (presumably due to nested functions)?

(Instead of the ones I'm used to where there only one frame pointer is 
visible at any time, and usually kept in a register.)

So you have two stacks; why shouldn't that be enough? (Normally only one is 
used.)

>So if I have something like f(3) in the
> source code, the corresponding runTimeStack is supposed to go
> something like
>
> LIT 3  //private machine code
> [1, 4, 10, 20, 3]
>
> ARGS 1 //ditto
> [1, 4, 10, 20] [3]
>
> CALL F<<20>>
> [1, 4, 10, 20] [3]

> I don't see how to create the new "stack" when I'm only given one
> stack to hold the data and another to hold the offsets.

It's not clear what you're trying to do. You haven't shown the stack of 
frame pointers.

I would guess that when F is called, it has to create some space on the data 
stack (for its local data), create a new frame pointer to point to that 
space, and push that frame pointer onto the frame pointer stack (or maybe it 
keeps the current one off the stack).

But if you are implementing something to do with such a language, then you 
need to find out a bit more about how these things are done.

(BTW what's the difference between .add and .push in your OP?)

-- 
Bartc 

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Thread

Creating a new stack from an exisiting one. Chad <cdalten@gmail.com> - 2012-11-03 07:45 -0700
  Re: Creating a new stack from an exisiting one. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-11-03 15:51 +0000
    Re: Creating a new stack from an exisiting one. Chad <cdalten@gmail.com> - 2012-11-03 09:22 -0700
      Re: Creating a new stack from an exisiting one. markspace <-@.> - 2012-11-03 11:20 -0700
      Re: Creating a new stack from an exisiting one. "BartC" <bc@freeuk.com> - 2012-11-03 18:58 +0000
      Re: Creating a new stack from an exisiting one. "Pascal J. Bourguignon" <pjb@informatimago.com> - 2012-11-04 00:49 +0100
      Re: Creating a new stack from an exisiting one. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-11-04 00:44 +0000
        Re: Creating a new stack from an exisiting one. "Pascal J. Bourguignon" <pjb@informatimago.com> - 2012-11-04 13:14 +0100
          Re: Creating a new stack from an exisiting one. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-11-04 12:48 +0000
            Re: Creating a new stack from an exisiting one. Thomas Richter <thor@math.tu-berlin.de> - 2012-11-04 14:14 +0100
              Re: Creating a new stack from an exisiting one. Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-11-04 15:38 +0000
            Re: Creating a new stack from an exisiting one. "Pascal J. Bourguignon" <pjb@informatimago.com> - 2012-11-04 14:41 +0100
          Re: Creating a new stack from an exisiting one. "BartC" <bc@freeuk.com> - 2012-11-04 14:11 +0000
            Re: Creating a new stack from an exisiting one. "Pascal J. Bourguignon" <pjb@informatimago.com> - 2012-11-04 16:00 +0100
          Re: Creating a new stack from an exisiting one. markspace <-@.> - 2012-11-04 11:02 -0800
          Re: Creating a new stack from an exisiting one. Martin Gregorie <martin@address-in-sig.invalid> - 2012-11-04 19:56 +0000
    Re: Creating a new stack from an exisiting one. Jeff Higgins <jeff@invalid.invalid> - 2012-11-03 16:46 -0400
      Re: Creating a new stack from an exisiting one. Jeff Higgins <jeff@invalid.invalid> - 2012-11-04 08:22 -0500
        Re: Creating a new stack from an exisiting one. Jeff Higgins <jeff@invalid.invalid> - 2012-11-04 11:30 -0500
          Re: Creating a new stack from an exisiting one. Jeff Higgins <jeff@invalid.invalid> - 2012-11-04 19:40 -0500
  Re: Creating a new stack from an exisiting one. Lew <lewbloch@gmail.com> - 2012-11-03 16:02 -0700

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