opelly/Stockfish
1
0
Fork 0
mirror of https://github.com/opelly27/Stockfish.git synced 2026-05-20 13:17:44 +00:00
Code Issues Packages Projects Releases Wiki Activity

Improve comments about DEPTH constants

Browse Source 
Also "fix" movepicker to allow depths between CHECKS and NO_CHECKS,
which makes them easier to tweak (not that they get tweaked hardly ever)
(This was more beneficial when there was a third stage to DEPTH_QS, but
it's still an improvement now)

closes https://github.com/official-stockfish/Stockfish/pull/5205

No functional change
This commit is contained in:
Dubslow
2023-04-04 22:55:52 -05:00
committed by Disservin
parent c14b69790a
commit ed79745bb9
5 changed files with 43 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/tt.cpp
+8 -4
View File
@@ -30,6 +30,10 @@
namespace Stockfish {
// DEPTH_ENTRY_OFFSET exists because 1) we use `bool(depth8)` as the occupancy check, but
// 2) we need to store negative depths for QS. (`depth8` is the only field with "spare bits":
// we sacrifice the ability to store depths greater than 1<<8 less the offset, as asserted below.)
// Populates the TTEntry with a new node's data, possibly
// overwriting an old position. The update is not atomic and can be racy.
void TTEntry::save(
@@ -40,14 +44,14 @@ void TTEntry::save(
move16 = m;
// Overwrite less valuable entries (cheapest checks first)
if (b == BOUND_EXACT || uint16_t(k) != key16 || d - DEPTH_OFFSET + 2 * pv > depth8 - 4
if (b == BOUND_EXACT || uint16_t(k) != key16 || d - DEPTH_ENTRY_OFFSET + 2 * pv > depth8 - 4
|| relative_age(generation8))
{
assert(d > DEPTH_OFFSET);
assert(d < 256 + DEPTH_OFFSET);
assert(d > DEPTH_ENTRY_OFFSET);
assert(d < 256 + DEPTH_ENTRY_OFFSET);
key16 = uint16_t(k);
depth8 = uint8_t(d - DEPTH_OFFSET);
depth8 = uint8_t(d - DEPTH_ENTRY_OFFSET);
genBound8 = uint8_t(generation8 | uint8_t(pv) << 2 | b);
value16 = int16_t(v);
eval16 = int16_t(ev);