1
0
Fork 0
mirror of https://github.com/sockspls/badfish synced 2025-04-29 16:23:09 +00:00

Unify sp_search() and search() step 1

Rewrite sp_search() to have same signature of search()

This is the first prerequistite step toward unification.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This commit is contained in:
Marco Costalba 2010-10-12 10:28:25 +02:00
parent 79a7647fe0
commit 37055ad002
2 changed files with 42 additions and 24 deletions

View file

@ -287,11 +287,14 @@ namespace {
template <NodeType PvNode>
Value search(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth, int ply);
template <NodeType PvNode>
void sp_search(Position& pos, SearchStack* ss, Value dumy, Value beta, Depth depth, int ply);
template <NodeType PvNode>
Value qsearch(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth, int ply);
template <NodeType PvNode>
void sp_search(SplitPoint* sp, int threadID);
void do_sp_search(SplitPoint* sp, int threadID);
template <NodeType PvNode>
Depth extension(const Position& pos, Move m, bool captureOrPromotion, bool moveIsCheck, bool singleEvasion, bool mateThreat, bool* dangerous);
@ -1555,11 +1558,21 @@ namespace {
// care of after we return from the split point.
template <NodeType PvNode>
void sp_search(SplitPoint* sp, int threadID) {
void do_sp_search(SplitPoint* sp, int threadID) {
assert(threadID >= 0 && threadID < ThreadsMgr.active_threads());
assert(ThreadsMgr.active_threads() > 1);
Position pos(*sp->pos, threadID);
SearchStack* ss = sp->sstack[threadID] + 1;
ss->sp = sp;
sp_search<PvNode>(pos, ss, Value(threadID), sp->beta, sp->depth, sp->ply);
}
template <NodeType PvNode>
void sp_search(Position& pos, SearchStack* ss, Value, Value beta, Depth depth, int ply) {
StateInfo st;
Move move;
Depth ext, newDepth;
@ -1568,18 +1581,20 @@ namespace {
bool isCheck, moveIsCheck, captureOrPromotion, dangerous;
int moveCount;
value = -VALUE_INFINITE;
SplitPoint* sp = ss->sp;
Move threatMove = sp->threatMove;
MovePicker& mp = *sp->mp;
int threadID = pos.thread();
Position pos(*sp->pos, threadID);
CheckInfo ci(pos);
SearchStack* ss = sp->sstack[threadID] + 1;
isCheck = pos.is_check();
// Step 10. Loop through moves
// Loop through all legal moves until no moves remain or a beta cutoff occurs
lock_grab(&(sp->lock));
while ( sp->bestValue < sp->beta
&& (move = sp->mp->get_next_move()) != MOVE_NONE
while ( sp->bestValue < beta
&& (move = mp.get_next_move()) != MOVE_NONE
&& !ThreadsMgr.thread_should_stop(threadID))
{
moveCount = ++sp->moveCount;
@ -1592,7 +1607,7 @@ namespace {
// Step 11. Decide the new search depth
ext = extension<PvNode>(pos, move, captureOrPromotion, moveIsCheck, false, sp->mateThreat, &dangerous);
newDepth = sp->depth - ONE_PLY + ext;
newDepth = depth - ONE_PLY + ext;
// Update current move
ss->currentMove = move;
@ -1605,8 +1620,8 @@ namespace {
&& !move_is_castle(move))
{
// Move count based pruning
if ( moveCount >= futility_move_count(sp->depth)
&& !(sp->threatMove && connected_threat(pos, move, sp->threatMove))
if ( moveCount >= futility_move_count(depth)
&& !(threatMove && connected_threat(pos, move, threatMove))
&& sp->bestValue > value_mated_in(PLY_MAX))
{
lock_grab(&(sp->lock));
@ -1614,11 +1629,11 @@ namespace {
}
// Value based pruning
Depth predictedDepth = newDepth - reduction<NonPV>(sp->depth, moveCount);
Depth predictedDepth = newDepth - reduction<NonPV>(depth, moveCount);
futilityValueScaled = ss->eval + futility_margin(predictedDepth, moveCount)
+ H.gain(pos.piece_on(move_from(move)), move_to(move));
if (futilityValueScaled < sp->beta)
if (futilityValueScaled < beta)
{
lock_grab(&(sp->lock));
@ -1640,13 +1655,13 @@ namespace {
&& !move_is_castle(move)
&& !move_is_killer(move, ss))
{
ss->reduction = reduction<PvNode>(sp->depth, moveCount);
ss->reduction = reduction<PvNode>(depth, moveCount);
if (ss->reduction)
{
Value localAlpha = sp->alpha;
Depth d = newDepth - ss->reduction;
value = d < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, DEPTH_ZERO, sp->ply+1)
: - search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, d, sp->ply+1);
value = d < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, DEPTH_ZERO, ply+1)
: - search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, d, ply+1);
doFullDepthSearch = (value > localAlpha);
}
@ -1660,7 +1675,7 @@ namespace {
ss->reduction = ONE_PLY;
Value localAlpha = sp->alpha;
value = -search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, newDepth-ss->reduction, sp->ply+1);
value = -search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, newDepth-ss->reduction, ply+1);
doFullDepthSearch = (value > localAlpha);
}
ss->reduction = DEPTH_ZERO; // Restore original reduction
@ -1670,15 +1685,15 @@ namespace {
if (doFullDepthSearch)
{
Value localAlpha = sp->alpha;
value = newDepth < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, DEPTH_ZERO, sp->ply+1)
: - search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, newDepth, sp->ply+1);
value = newDepth < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, DEPTH_ZERO, ply+1)
: - search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, newDepth, ply+1);
// Step extra. pv search (only in PV nodes)
// Search only for possible new PV nodes, if instead value >= beta then
// parent node fails low with value <= alpha and tries another move.
if (PvNode && value > localAlpha && value < sp->beta)
value = newDepth < ONE_PLY ? -qsearch<PV>(pos, ss+1, -sp->beta, -sp->alpha, DEPTH_ZERO, sp->ply+1)
: - search<PV>(pos, ss+1, -sp->beta, -sp->alpha, newDepth, sp->ply+1);
if (PvNode && value > localAlpha && value < beta)
value = newDepth < ONE_PLY ? -qsearch<PV>(pos, ss+1, -beta, -sp->alpha, DEPTH_ZERO, ply+1)
: - search<PV>(pos, ss+1, -beta, -sp->alpha, newDepth, ply+1);
}
// Step 16. Undo move
@ -1694,10 +1709,10 @@ namespace {
sp->bestValue = value;
if (value > sp->alpha)
{
if (!PvNode || value >= sp->beta)
if (!PvNode || value >= beta)
sp->stopRequest = true;
if (PvNode && value < sp->beta) // We want always sp->alpha < sp->beta
if (PvNode && value < beta) // We want always sp->alpha < beta
sp->alpha = value;
sp->parentSstack->bestMove = ss->bestMove = move;
@ -2150,6 +2165,7 @@ namespace {
ss->excludedMove = MOVE_NONE;
ss->skipNullMove = false;
ss->reduction = DEPTH_ZERO;
ss->sp = NULL;
if (i < 3)
ss->killers[0] = ss->killers[1] = ss->mateKiller = MOVE_NONE;
@ -2362,9 +2378,9 @@ namespace {
threads[threadID].state = THREAD_SEARCHING;
if (threads[threadID].splitPoint->pvNode)
sp_search<PV>(threads[threadID].splitPoint, threadID);
do_sp_search<PV>(threads[threadID].splitPoint, threadID);
else
sp_search<NonPV>(threads[threadID].splitPoint, threadID);
do_sp_search<NonPV>(threads[threadID].splitPoint, threadID);
assert(threads[threadID].state == THREAD_SEARCHING);

View file

@ -47,6 +47,7 @@ const int PLY_MAX_PLUS_2 = 102;
/// search thread has its own array of SearchStack objects, indexed by the
/// current ply.
struct EvalInfo;
struct SplitPoint;
struct SearchStack {
Move currentMove;
@ -57,6 +58,7 @@ struct SearchStack {
Depth reduction;
Value eval;
bool skipNullMove;
SplitPoint* sp;
};