Re: [cc65] Macro/asm problem

--- Ullrich von Bassewitz <uz@musoftware.de> wrote:
> The inline assembler doesn't support the full ca65
> syntax.

Well, it does work with optimizations turned off.

>         #define WAITSUZY        \
>             asm ("L1:");        \
>             asm ("bit $fc92");  \
>             asm ("bmi L1")
> 
> One problem is that you will run into trouble when
> using this macro twice
> within one function, since the label is redefined. A
> solution would be to pass
> the label number as a macro argument.

That would definitely be a problem, since this macro
could very well be used multiple times in one
function.  I could do something like:

while ($fc92 & 0x80);

but that compiles to something like lda $fc92, and
#$80, beq *-7.  I think the bit/bmi is cheaper.
 
Your suggestion about adding a label number to the
macro might work, but a little ugly.  Any other
suggestions?

Hmmm, my best bet might be to use the while loop from
above, and just let the programmer worry about using
the bit/bmi form if they need to shave a few cycles
out of a loop.

--
Shawn Jefferson



	
		
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