RE: [avr-gcc-list] GCC guru question (progue/epilogue sequences)

[Marc R. Wetzel]

Did you had a look at ethernut? Something very useful is already there. This project

looks always for contributors.

 

To your question:

 

if an interrupt occurs your kernel has no chance to save any registers. so the pro/epilogue is very helpful.

your kernel will be interrupted and it is not clear -- when.

 

Look at the ethernut-way: it uses a kind of wrapper for any possible interrupt source available.

and if you attach an real interrupt-handler to it, it will be called.

 

Hopefully I understand your question right...

 

/Marc

-----Original Message-----
From: address@hidden [mailto:address@hiddenOn Behalf Of Marko Panger
Sent: Tuesday, July 09, 2002 10:56 PM
To: AVR Mailing List
Subject: [avr-gcc-list] GCC guru question (progue/epilogue sequences)

Hi all !!

 

I realy hope somebody could answer the following question. I will try to explain the situation and my problem.

 

So... I am writting a RTOS and I would like to have interrupt handlers written in C language. If I define a function as a INTERRUPT or SIGNAL the compiler generates the prologue/epilogue sequence automaticaly. But I don't need this. Registers saving an restoring is managed by my kernel.

 

There is another possibility. I could decalre the interrupt function with NAKED attribute. This would be fine for me since the compiler doesn't generate the prologue/epilogue sequence. But here comes the problem. What will happen if I decalare some local variables wich are putted on the stack ?

 

I was wondering if is possible to write my own pro/epi sequences ? How will I now how many variables are putted onto the stack ?