HCha/Stockfish
1
0
Fork 0
mirror of https://github.com/HChaZZY/Stockfish.git synced 2025-12-20 00:56:39 +08:00
Code Issues Packages Projects Releases Wiki Activity

Avoid a needless locking in sp_search()

Browse Source 
Only in less then 2% of cases we have a new sp->bestValue,
so check before to lock and save a costly locking
most of the times.

Patch suggested by Joona.

No functional search.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This commit is contained in:
Marco Costalba
2009-10-19 07:44:06 +01:00
parent f0b0a3b135
commit 51c3af9dd0
1 changed files with 14 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
src/search.cpp
View File

@@ -1759,21 +1759,24 @@ namespace {
break;
// New best move?
lock_grab(&(sp->lock));
if (value > sp->bestValue && !thread_should_stop(threadID))
if (value > sp->bestValue) // Less then 2% of cases
{
sp->bestValue = value;
if (sp->bestValue >= sp->beta)
lock_grab(&(sp->lock));
if (value > sp->bestValue && !thread_should_stop(threadID))
{
sp_update_pv(sp->parentSstack, ss, sp->ply);
for (int i = 0; i < ActiveThreads; i++)
if (i != threadID && (i == sp->master || sp->slaves[i]))
Threads[i].stop = true;
sp->bestValue = value;
if (sp->bestValue >= sp->beta)
{
sp_update_pv(sp->parentSstack, ss, sp->ply);
for (int i = 0; i < ActiveThreads; i++)
if (i != threadID && (i == sp->master || sp->slaves[i]))
Threads[i].stop = true;
sp->finished = true;
}
sp->finished = true;
}
}
lock_release(&(sp->lock));
}
lock_release(&(sp->lock));
}
lock_grab(&(sp->lock));