On Tue, 4 Jun 2002, Scott Dattalo wrote:

>On Mon, 3 Jun 2002, Dmitriy A. Kiryashov wrote:
>
>> Hi guys. Here is tiny challendge to warm up. ;)
>>
>> We have X variable. What is shortest possible
>> code to obtain 2X + 1 result back into X cell ?
>>
>
>How about:
>
>sdcc -S -mpic14 c.c
>
>...
>
>;;      Unrolled 8 X 8 multiplication
>;#CSRC  c.c 71
>;  achar0 = achar0*2 + 1;
>        MOVF    _achar0,W       ;key=000,flow seq=001
>        MOVWF   r0x20   ;key=001,flow seq=001
>        ADDWF   r0x20,F ;key=002,flow seq=001
>        CLRF    r0x21   ;key=003,flow seq=001
>        RLF     r0x21,F ;key=004,flow seq=001
>        INCF    r0x20,W ;key=005,flow seq=001
>        MOVWF   _achar0 ;key=006,flow seq=001
>
>I think I hate C compilers. :)

That's a 8x8 multiplication by a *constant*, no ? Did you not draw upon
Dmitry's excellent multiplier/divider code to generate that sort of code ?

Peter

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