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almost working now

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Ole Morud
2025-12-15 22:51:10 +01:00
parent 25705d6cd6
commit 2f65828ae2
4 changed files with 1487 additions and 529 deletions
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147
codegen.c
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@@ -1,104 +1,8 @@
#define CODEGEN
#include "base.h"
#include <stdlib.h>
#include <stdio.h>
static bitboard bishop_attacks_from_index_slow(enum square_index sq, bitboard occ)
{
const enum rank_index rank = index_to_rank(sq);
const enum file_index file = index_to_file(sq);
bitboard atk = 0ULL;
/* following loops assume rank and file types are unsigned, which relies on C23 enums */
_Static_assert(((enum rank_index)0) - ((enum rank_index)1) > ((enum rank_index)0));
_Static_assert(((enum file_index)0) - ((enum file_index)1) > ((enum file_index)0));
enum rank_index walk_rank;
enum file_index walk_file;
for (walk_rank = rank+1, walk_file = file+1;
walk_rank <= RANK_INDEX_8 && walk_file <= FILE_INDEX_H;
++walk_rank, ++walk_file) {
const bitboard sq = SQ_MASK_FROM_RF(walk_rank, walk_file);
atk |= sq;
if (occ & sq) {
break;
}
}
for (walk_rank = rank+1, walk_file = file-1;
walk_rank <= RANK_INDEX_8 && walk_file <= FILE_INDEX_H;
++walk_rank, --walk_file) {
const bitboard sq = SQ_MASK_FROM_RF(walk_rank, walk_file);
atk |= sq;
if (occ & sq) {
break;
}
}
for (walk_rank = rank-1, walk_file = file+1;
walk_rank <= RANK_INDEX_8 && walk_file <= FILE_INDEX_H;
--walk_rank, ++walk_file) {
const bitboard sq = SQ_MASK_FROM_RF(walk_rank, walk_file);
atk |= sq;
if (occ & sq) {
break;
}
}
for (walk_rank = rank-1, walk_file = file-1;
walk_rank <= RANK_INDEX_8 && walk_file <= FILE_INDEX_H;
--walk_rank, --walk_file) {
const bitboard sq = SQ_MASK_FROM_RF(walk_rank, walk_file);
atk |= sq;
if (occ & sq) {
break;
}
}
return atk;
}
static bitboard rook_attacks_from_index_slow(enum square_index sq, bitboard occ)
{
const enum rank_index rank = index_to_rank(sq);
const enum file_index file = index_to_file(sq);
bitboard atk = 0ULL;
/* following loops assume rank and file types are unsigned, which relies on C23 enums */
_Static_assert(((enum rank_index)0) - ((enum rank_index)1) > ((enum rank_index)0));
_Static_assert(((enum file_index)0) - ((enum file_index)1) > ((enum file_index)0));
for (enum rank_index walk_rank = rank+1; walk_rank <= RANK_INDEX_8; ++walk_rank) {
const bitboard sq = SQ_MASK_FROM_RF(walk_rank, file);
atk |= sq;
if (occ & sq) {
break;
}
}
for (enum rank_index walk_rank = rank-1; walk_rank <= RANK_INDEX_8; --walk_rank) {
const bitboard sq = SQ_MASK_FROM_RF(walk_rank, file);
atk |= sq;
if (occ & sq) {
break;
}
}
for (enum file_index walk_file = file+1; walk_file <= FILE_INDEX_H; ++walk_file) {
const bitboard sq = SQ_MASK_FROM_RF(rank, walk_file);
atk |= sq;
if (occ & sq) {
break;
}
}
for (enum file_index walk_file = file-1; walk_file <= FILE_INDEX_H; --walk_file) {
const bitboard sq = SQ_MASK_FROM_RF(rank, walk_file);
atk |= sq;
if (occ & sq) {
break;
}
}
return atk;
}
/* gets the next number with the same bitcount, unless it overflows, in which
* it returns the first number with popcount+1 */
uint64_t next_magic(uint64_t seed) {
@@ -116,21 +20,6 @@ uint64_t next_magic(uint64_t seed) {
return seed;
}
uint64_t rand64() {
union {
uint64_t v;
uint16_t vs[4];
} x = {
.vs = {
(uint16_t)rand(),
(uint16_t)rand(),
(uint16_t)rand(),
(uint16_t)rand(),
}
};
return x.v;
}
int main()
{
@@ -146,6 +35,8 @@ int main()
index bishop_relevant_bits[9] = {0};
size_t bishop_relevant_bits_count = 0;
bitboard between_lookup[SQ_INDEX_COUNT][SQ_INDEX_COUNT];
for (enum square_index sq_index = SQ_INDEX_BEGIN; sq_index < SQ_INDEX_COUNT; ++sq_index) {
enum file_index file = index_to_file(sq_index);
enum rank_index rank = index_to_rank(sq_index);
@@ -183,7 +74,7 @@ int main()
occ |= ((test >> i) & 1ULL) << rook_relevant_bits[i];
}
atk = rook_attacks_from_index_slow(sq_index, occ);
atk = rook_attacks_from_index(sq_index, occ);
const size_t hash = ((occ * magic) >> (64ULL-12));
@@ -239,7 +130,7 @@ int main()
occ |= ((test >> i) & 1ULL) << bishop_relevant_bits[i];
}
atk = bishop_attacks_from_index_slow(sq_index, occ);
atk = bishop_attacks_from_index(sq_index, occ);
const size_t hash = ((occ * magic) >> (64ULL-9));
@@ -258,6 +149,16 @@ int main()
next_bishop_magic:
}
}
/* BETWEEN TABLE
* ===================== */
{
for (enum square_index i = SQ_INDEX_BEGIN; i < SQ_INDEX_COUNT; ++i) {
for (enum square_index j = SQ_INDEX_BEGIN; j < SQ_INDEX_COUNT; ++j) {
between_lookup[i][j] = between_mask(i, j);
}
}
}
}
/* --- write to files --- */
@@ -336,6 +237,24 @@ int main()
fprintf(f,"};\n");
}
{ /* between table */
FILE* f = fopen("between_lookup.h", "w");
if (!f) {
perror("fopen");
exit(EXIT_FAILURE);
}
fprintf(f, "static const bitboard between_lookup[SQ_INDEX_COUNT][SQ_INDEX_COUNT] = {\n");
for (enum square_index i = SQ_INDEX_BEGIN; i < SQ_INDEX_COUNT; ++i) {
fprintf(f, "[%s] = {\n", square_index_str[i]);
for (enum square_index j = SQ_INDEX_BEGIN; j < SQ_INDEX_COUNT; ++j) {
fprintf(f, "0x%016"BITBOARD_FMT_X"ULL, \n", between_lookup[i][j]);
}
fprintf(f, "\n},\n");
}
fprintf(f,"};\n");
}
#undef TAB
#undef NL
}