bitboards.c

#include "bitboards.h"
#include <stdio.h>

//magic pawn
const int pawnMagics[64] = {
        63, 30, 3, 32, 25, 41, 22, 33, 15, 50, 42, 13, 11, 53, 19, 34, 61, 29, 2,
        51, 21, 43, 45, 10, 18, 47, 1, 54, 9, 57, 0, 35, 62, 31, 40, 4, 49, 5, 52,
        26, 60, 6, 23, 44, 46, 27, 56, 16, 7, 39, 48, 24, 59, 14, 12, 55, 38, 28,
        58, 20, 37, 17, 36, 8
};

int popBit(uint64_t *bb) {
    uint64_t b = *bb ^ (*bb - 1);
    unsigned int fold = (unsigned) ((b & 0xffffffff) ^ (b >> 32));
    *bb &= (*bb - 1);
    return pawnMagics[(fold * 0x783a9b23) >> 26];
}

int countBits(uint64_t b) {
    int r;
    for(r = 0; b; r++, b &= b - 1);
    return r;
}

void printBitboard(uint64_t bb) {
    uint64_t shiftMe = 1ULL;

    int rank = 0;
    int file = 0;
    int sq = 0;
    int sq64 = 0;

    printf("\n");
    for(rank= RANK_8;  rank >= RANK_1; rank--) {
        for(file = FILE_A; file <= FILE_H; file++) {
            sq = FR2SQ(file,rank);
            sq64 = SQ64(sq);

            if((shiftMe << sq64) & bb)
                printf("X");
            else
                printf("-");
        }
        printf("\n");
    }
    printf("\n\n");
}