Re: [Freemint-discuss] "r" modifiers in osbind.h & falcon.h

[Vincent R. <vin...@fr...>]

On 04/04/2024 at 10:13, Thorsten Otto wrote:
> Maybe the constraints could be relaxed to "ri" so that immediate 
> constants can be pushed as such. But thas has to be carefully checked.

Yes, EmuTOS BIOS bindings do something similar with "nr":
https://github.com/emutos/emutos/blob/master/include/biosbind.h

If the operand is a constant, it is used directly.

If it is from memory, then GCC automatically puts it into a register 
first, to avoid the stack issue mentioned by Thorsten. This is really 
sad, GCC inline assembly syntax isn't suited for stack manipulation.

BTW, I don't know what if there is a difference between "i" and "n" for 
m68k:
https://gcc.gnu.org/onlinedocs/gcc/Simple-Constraints.html

-- 
Vincent Rivière