[MSX] MAP update, 2005-05-12

[Laurens Holst]

Patriek Lesparre wrote:
>> * Replaced the Div16 16-bits division routine with a faster one by 
>> Flyguille. The speed gain seems quite humble, 3 T-states, but this one 
>> can be unrolled to gain quite some speed.
> 
> Another 4 t-states can be saved by replacing
> XOR A   ; 5 t-states
> LD L,A  ; 5 t-states
> LD H,A  ; 5 t-states
> with
> LD HL,0 ; 11 t-states
> 
> The first sequence of instructions are only faster if both A and HL are 
> supposed to be 0, which is not the case in this routine.

Thanks! Though it’s only 3 states, as I’m also counting the additional 
M1 wait state. If you don’t mind, I’ll just keep the credit for you on 
this list, otherwise the document’ll become a maze of thanks this thanks 
that ^_^. Even though the tweak effectively doubles the gain in speed ;)


~Grauw

-- 
Ushiko-san! Kimi wa doushite, Ushiko-san!!