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Ole Morud
2025-12-09 02:34:33 +01:00
parent fe2e026f1e
commit 25705d6cd6
4 changed files with 701 additions and 395 deletions
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140
codegen.c
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@@ -3,6 +3,102 @@
#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) {
@@ -38,19 +134,19 @@ uint64_t rand64() {
int main()
{
struct magic rook_magics[SQUARE_INDEX_COUNT] = {0ULL};
bitboard rook_attacks[SQUARE_INDEX_COUNT][1<<12ULL] = {0};
struct magic rook_magics[SQ_INDEX_COUNT] = {0ULL};
bitboard rook_attacks[SQ_INDEX_COUNT][1<<12ULL] = {0};
index rook_relevant_bits[12] = {0};
size_t rook_relevant_bits_count = 0;
struct magic bishop_magics[SQUARE_INDEX_COUNT] = {0ULL};
bitboard bishop_attacks[SQUARE_INDEX_COUNT][1<<9ULL] = {0};
struct magic bishop_magics[SQ_INDEX_COUNT] = {0ULL};
bitboard bishop_attacks[SQ_INDEX_COUNT][1<<9ULL] = {0};
index bishop_relevant_bits[9] = {0};
size_t bishop_relevant_bits_count = 0;
for (enum square_index sq_index = SQUARE_INDEX_BEGIN; sq_index < SQUARE_INDEX_COUNT; ++sq_index) {
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);
fprintf(stderr, "%s ", square_index_display[sq_index]);
@@ -61,16 +157,15 @@ int main()
/* generate attack mask */
bitboard atk_mask = 0;
{
atk_mask |= FILE_MASK(file) & ~(RANKMASK_1 | RANKMASK_8);
atk_mask |= RANK_MASK(rank) & ~(FILEMASK_A | FILEMASK_H);
atk_mask &= ~SQUARE_MASK_FROM_RF(rank, file);
atk_mask |= FILE_MASK(file) & ~(RANK_MASK_1 | RANK_MASK_8);
atk_mask |= RANK_MASK(rank) & ~(FILE_MASK_A | FILE_MASK_H);
atk_mask &= ~SQ_MASK_FROM_RF(rank, file);
/* populate relevant bits array */
rook_relevant_bits_count = 0;
bitboard x = atk_mask;
while (x) {
const index lsb = bitboard_lsb(x) - 1;
x &= ~(1ULL<<(lsb));
const index lsb = bitboard_pop_lsb(&x);
rook_relevant_bits[rook_relevant_bits_count++] = lsb;
}
}
@@ -117,16 +212,15 @@ int main()
bitboard atk_mask = 0;
{
atk_mask |= diagonals_from_index(sq_index);
atk_mask &= ~(RANKMASK_1 | RANKMASK_8);
atk_mask &= ~(FILEMASK_A | FILEMASK_H);
atk_mask &= ~SQUARE_MASK_FROM_RF(rank, file);
atk_mask &= ~(RANK_MASK_1 | RANK_MASK_8);
atk_mask &= ~(FILE_MASK_A | FILE_MASK_H);
atk_mask &= ~SQ_MASK_FROM_RF(rank, file);
/* populate relevant bits array */
bishop_relevant_bits_count = 0;
bitboard x = atk_mask;
while (x) {
const index lsb = bitboard_lsb(x) - 1;
x &= ~(1ULL<<(lsb));
const index lsb = bitboard_pop_lsb(&x);
bishop_relevant_bits[bishop_relevant_bits_count++] = lsb;
}
}
@@ -178,8 +272,8 @@ int main()
}
fprintf(f, "#pragma once\n");
fprintf(f, "static const struct magic mbb_rook[SQUARE_INDEX_COUNT] = {\n");
for (enum square_index i = SQUARE_INDEX_BEGIN; i < SQUARE_INDEX_COUNT; i++) {
fprintf(f, "static const struct magic mbb_rook[SQ_INDEX_COUNT] = {\n");
for (enum square_index i = SQ_INDEX_BEGIN; i < SQ_INDEX_COUNT; i++) {
fprintf(f,
TAB "[%s] = (struct magic) {"
NL TAB " .magic = 0x%016"BITBOARD_FMT_X"ULL,"
@@ -194,8 +288,8 @@ int main()
fprintf(f,"\n");
fprintf(f, "static const bitboard rook_attacks[SQUARE_INDEX_COUNT][1ULL<<12ULL] = {\n");
for (enum square_index sq = SQUARE_INDEX_BEGIN; sq < SQUARE_INDEX_COUNT; ++sq) {
fprintf(f, "static const bitboard rook_attacks[SQ_INDEX_COUNT][1ULL<<12ULL] = {\n");
for (enum square_index sq = SQ_INDEX_BEGIN; sq < SQ_INDEX_COUNT; ++sq) {
fprintf(f, "[%s] = {\n", square_index_str[sq]);
for (size_t i = 0; i < sizeof rook_attacks[sq] / sizeof *rook_attacks[sq]; i++) {
fprintf(f, "0x%016"BITBOARD_FMT_X"ULL, \n", rook_attacks[sq][i]);
@@ -215,8 +309,8 @@ int main()
}
fprintf(f, "\n");
fprintf(f, "static const struct magic mbb_bishop[SQUARE_INDEX_COUNT] = {\n");
for (enum square_index i = SQUARE_INDEX_BEGIN; i < SQUARE_INDEX_COUNT; i++) {
fprintf(f, "static const struct magic mbb_bishop[SQ_INDEX_COUNT] = {\n");
for (enum square_index i = SQ_INDEX_BEGIN; i < SQ_INDEX_COUNT; i++) {
fprintf(f,
TAB "[%s] = (struct magic) {"
NL TAB " .magic = 0x%016"BITBOARD_FMT_X"ULL,"
@@ -231,8 +325,8 @@ int main()
fprintf(f,"\n");
fprintf(f, "static const bitboard bishop_attacks[SQUARE_INDEX_COUNT][1ULL<<9ULL] = {\n");
for (enum square_index sq = SQUARE_INDEX_BEGIN; sq < SQUARE_INDEX_COUNT; ++sq) {
fprintf(f, "static const bitboard bishop_attacks[SQ_INDEX_COUNT][1ULL<<9ULL] = {\n");
for (enum square_index sq = SQ_INDEX_BEGIN; sq < SQ_INDEX_COUNT; ++sq) {
fprintf(f, "[%s] = {\n", square_index_str[sq]);
for (size_t i = 0; i < sizeof bishop_attacks[sq] / sizeof *bishop_attacks[sq]; i++) {
fprintf(f, "0x%016"BITBOARD_FMT_X"ULL, \n", bishop_attacks[sq][i]);