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Subject: Re: speed question

Author: Uri Blass

Date: 09:48:45 02/21/03

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On February 21, 2003 at 11:15:24, Dezhi Zhao wrote:

>On February 21, 2003 at 04:14:49, Uri Blass wrote:
>
>>On February 20, 2003 at 13:51:37, Filip Tvrzsky wrote:
>>
>>>On February 20, 2003 at 12:49:39, Uri Blass wrote:
>>>
>>>>
>>>>I guess that you mean
>>>>#define gen_dat_i_mpromote (gen_dat[i].m & (63 << 16))
>>>>
>>>>I guess that the laternative that I tried
>>>>
>>>>#define to(x) (((x)>>8)&255) was also bad
>>>>and better was
>>>>#define to(x) (((x)&255<<8)
>>>>
>>>>I guess that in that case I need to change some more code
>>>>
>>>>For example
>>>>
>>>>I have today some cases when I have
>>>>switch(m.bits)
>>>>case 1:
>>>>case 17:
>>>>...
>>>>
>>>>in that case I need to say case 1<<24 and in order not to have an ugly code
>>>>I need to have more constants for 2^24,2^24*17,...
>>>>
>>>>I can use
>>>>enum
>>>>{
>>>> bits1=16777216
>>>> bits17=
>>>>...
>>>>}
>>>>
>>>>Uri
>>>
>>>#define to(x) (((x)>>8)&255) is definitely worse than #define to(x)
>>>(((x)&255<<8) because in the first case the shifting is done in run-time and in
>>>the second during compilation. Note also that the result of both macros is
>>>different.
>>
>>Yes
>>
>>This is an important note.
>>
>>I did not do the mistake of assuming that they are the same but I see that I
>>have problems.
>>
>>I cannot use my usual macros after that translate
>>
>>for example
>>
>>I had if (piece(m.b.to))=PAWN) in my code
>>I cannot transalate it to
>>if (piece(to(m))==PAWN)  because to(m) does not get something between 0 and 63
>>after the change and it seem that I cannot do it faster in this case.
>>
>
>you probabaly need another inline function or micro here:
>
>#define IsPawn(move) (piece(move.b.to) == PAWN)

note that piece() is not a function and it is in my defines

#define piece(square) ((info[square])&7)

The point is that info[64] include for every square both the color and both the
piece and the piece can be accesed by the array info[64] that is an array of
int.

>
>If you are using VC, inline functions are prefered. You can easily browse these
>inline fuctions. And the compiler does type checking that is certainly helpful.

I do not see a function that I should inline in that case because there is no
function in the code that I posted(only macros).

Do you suggest to start changing my code by adding
#define IsPawn(move) (piece(move.b.to) == PAWN) and only later to change my
structure and change my definition to something like

#define IsPawn(move) (piece(to(m)>>8)==PAWN)

Maybe it is a good idea(first to do the code more readable and later changing
the data structure is easier).

Uri



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