On 3/17/07, John Dammeyer <johnd@autoartisans.com> wrote:
> Hi,
>
> Just for fun I took Orin's version and compiled it with the Bytecraft C.
>
> It took 33 words including saving the argument which takes 3.

Interesting.

I was thinking that this was a mistake:

>                                      while ( len-- )
> 0998 1283    BCF    STATUS,RP0        {
> 0999 1703    BSF    STATUS,RP1
> 099A 0847    MOVF   147,W
> 099B 03C7    DECF   147
> 099C 3800    IORLW  00h                   Delay_10xUs_2MHz(DITLEN);
> 099D 1903    BTFSC  STATUS,Z
> 099E 29A6    GOTO   09A6h
> 099F 3064    MOVLW  64h
> 09A0 118A    BCF    PCLATH,3
> 09A1 160A    BSF    PCLATH,4
> 09A2 2737    CALL   1737h
> 09A3 158A    BSF    PCLATH,3
> 09A4 120A    BCF    PCLATH,4
> 09A5 2998    GOTO   0998h             }

And the code agrees.  I should have done:

do {
    Delay();
} while ( --len );

Which the compiler should be able to optimize nicely.  Postfix
operators tend to generate extra code.  This change is only safe since
I know I'm going through the loop at least once.

Orin.
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