kate/BadFish
1
0
Fork 0
mirror of https://github.com/sockspls/badfish synced 2025-04-29 16:23:09 +00:00
Code Issues Releases Wiki Activity

Lookup square distance instead of calculate on the fly

Browse source 
Microptimization that gives a +0.7% speed increase.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This commit is contained in:
Marco Costalba 2011-09-11 10:00:52 +01:00
parent 6963c3802d
commit b706165527
2 changed files with 10 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

11
src/bitboard.cpp
View file

@ -56,6 +56,7 @@ Bitboard RookPseudoAttacks[64];
Bitboard QueenPseudoAttacks[64];
uint8_t BitCount8Bit[256];
int SquareDistance[64][64];
namespace {
@ -154,6 +155,13 @@ Square pop_1st_bit(Bitboard* bb) {
void init_bitboards() {
for (Bitboard b = 0; b < 256; b++)
BitCount8Bit[b] = (uint8_t)count_1s<CNT32_MAX15>(b);
for (Square s1 = SQ_A1; s1 <= SQ_H8; s1++)
for (Square s2 = SQ_A1; s2 <= SQ_H8; s2++)
SquareDistance[s1][s2] = Max(file_distance(s1, s2), rank_distance(s1, s2));
SquaresByColorBB[DARK] = 0xAA55AA55AA55AA55ULL;
SquaresByColorBB[LIGHT] = ~SquaresByColorBB[DARK];
@ -194,9 +202,6 @@ void init_bitboards() {
AttackSpanMask[c][s] = in_front_bb(c, s) & neighboring_files_bb(s);
}
for (Bitboard b = 0; b < 256; b++)
BitCount8Bit[b] = (uint8_t)count_1s<CNT32_MAX15>(b);
for (int i = 0; i < 64; i++)
if (!CpuIs64Bit) // Matt Taylor's folding trick for 32 bit systems
{

3
src/types.h
View file

@ -348,6 +348,7 @@ const Value QueenValueEndgame = Value(0x9FE);
extern const Value PieceValueMidgame[17];
extern const Value PieceValueEndgame[17];
extern int SquareDistance[64][64];
inline Value piece_value_midgame(Piece p) {
return PieceValueMidgame[p];
@ -440,7 +441,7 @@ inline int rank_distance(Square s1, Square s2) {
}
inline int square_distance(Square s1, Square s2) {
return Max(file_distance(s1, s2), rank_distance(s1, s2));
return SquareDistance[s1][s2];
}
inline char file_to_char(File f) {