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Simplify sliding_attacks()

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Easy, almost trivial simplification, I don't understand
how I missed this before !!

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This commit is contained in:
Marco Costalba 2011-06-21 18:48:14 +01:00
parent e7413417ce
commit fe26967ea0
2 changed files with 6 additions and 9 deletions
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14
src/bitboard.cpp
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@ -252,7 +252,7 @@ void init_bitboards() {
namespace {
Bitboard sliding_attacks(Square sq, Bitboard occupied, Square delta[], Bitboard excluded) {
Bitboard sliding_attacks(Square sq, Bitboard occupied, Square delta[]) {
Bitboard attacks = 0;
@ -260,9 +260,7 @@ namespace {
{
Square s = sq + delta[i];
while ( square_is_ok(s)
&& square_distance(s, s - delta[i]) == 1
&& !bit_is_set(excluded, s))
while (square_is_ok(s) && square_distance(s, s - delta[i]) == 1)
{
set_bit(&attacks, s);
@ -302,22 +300,22 @@ namespace {
const int MagicBoosters[][8] = { { 3191, 2184, 1310, 3618, 2091, 1308, 2452, 3996 },
{ 1059, 3608, 605, 3234, 3326, 38, 2029, 3043 } };
RKISS rk;
Bitboard occupancy[4096], reference[4096], excluded, b;
Bitboard occupancy[4096], reference[4096], edges, b;
int key, maxKey, index, booster, offset = 0;
for (Square s = SQ_A1; s <= SQ_H8; s++)
{
excluded = ((Rank1BB | Rank8BB) & ~rank_bb(s)) | ((FileABB | FileHBB) & ~file_bb(s));
edges = ((Rank1BB | Rank8BB) & ~rank_bb(s)) | ((FileABB | FileHBB) & ~file_bb(s));
attack[s] = &attTable[offset];
mask[s] = sliding_attacks(s, EmptyBoardBB, delta, excluded);
mask[s] = sliding_attacks(s, EmptyBoardBB, delta) & ~edges;
shift[s] = (CpuIs64Bit ? 64 : 32) - count_1s<CNT32_MAX15>(mask[s]);
// Use Carry-Rippler trick to enumerate all subsets of mask[s]
b = maxKey = 0;
do {
occupancy[maxKey] = b;
reference[maxKey++] = sliding_attacks(s, b, delta, EmptyBoardBB);
reference[maxKey++] = sliding_attacks(s, b, delta);
b = (b - mask[s]) & mask[s];
} while (b);

1
src/search.cpp
View file

@ -1649,7 +1649,6 @@ split_point_start: // At split points actual search starts from here
assert(move_is_ok(m));
assert(threat && move_is_ok(threat));
assert(!pos.move_gives_check(m));
assert(!pos.move_is_capture(m) && !move_is_promotion(m));
assert(!pos.move_is_passed_pawn_push(m));