Simultaneous Global and Local Variable References

pjv

Hi All;

In assembler I wish to have some local variables identified by the :VarName convention, but also access the same variable with a different but Global name. When I try to double define it, the Global of course limits the range of the Local, and defeats the intent

Is there a trick to make·this be possible?

Many thanks,

Cheers,

Peter (pjv)
·

BradC

Not really, no. If you are defining a global at that address, why would you also want a local ?

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Life may be "too short", but it's the longest thing we ever do.

VIRAND

Name an unused HUBRAM address as a CONstant and use LONG[noparse][[/noparse]NAME]?
That method is so lost in left field it doesn't know the name of the game, but I use it when I need globals.
You may be able to find unused addresses at 32000, or OFFSCREEN_BUFFER, or near STACK.
In PASM:

   rdlong register, pname 'get value of LONG[noparse][[/noparse]NAME]
   wrong register2,pname 'change value of LONG[noparse][[/noparse]NAME]
---
register1 long something
register2 long somevalue
pname    long NAME     'or is it @NAME?

It is unfortunately hard to find addresses in DAT space, although they tend to be offset by 16 bytes if you do.
I have a worse hack to do that with, by using a bizarre unusual value like $ABADF00D and searching
the whole hub for it using a variable to count to its address. Very inefficient.

Maybe not what you want. I'd wait for a better answer. Mine is awful.

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I should be typing in Spin now.

Phil Pilgrim (PhiPi)

Did you try putting the :local label before the global one? That will only work for one variable, though. Most assemblers have an EQU pseudo-op for stuff like this.

-Phil

pjv

Thanks for the suggestions.

@Brad... probably that I am lazy, and wanted to include a generic piece of code into several assembly cogs without going renaming the variables in each duplicate, yet still trying to access the routines individually.

@VIRAND.... I'm messing with assembler here, so I'm not sure how your comments apply.

@Phil.... I tried that, and as you say, ony a single variable is not enough. I was hoping that I could do some kind of equate in the constants section, but a label with a leading colon seems not permitted there.

Cheers,

Peter (pjv)

Post Edited (pjv) : 2/8/2010 2:10:05 AM GMT

BradC

Homespun has a very basic #define capability where you can define a symbol and use the contents of that to replace the symbol in the code. That's probably as close as you are going to get without moving to a full macro pre-processor.

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Life may be "too short", but it's the longest thing we ever do.