HCha/Stockfish
1
0
Fork 0
mirror of https://github.com/HChaZZY/Stockfish.git synced 2025-12-19 00:26:33 +08:00
Code Issues Packages Projects Releases Wiki Activity

Get rid of ReducedStateInfo struct

Browse Source 
ReducedStateInfo is a redundant struct that is also
prone to errors, indeed must be updated any time is
updated StateInfo. It is a trick to partial copy a
StateInfo object in do_move().

This patch takes advantage of builtin macro offsetof()
to directly calculate the number of quad words to copy.
Note that we still use memcpy to do the actual job of
copying the (48 bytes) of data.

Idea by Richard Vida.

No functional and no performance change.
This commit is contained in:
Marco Costalba
2012-10-28 17:12:40 +01:00
parent ad1941fd00
commit 13f90a30ef
2 changed files with 9 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
src/position.cpp
View File

@@ -770,9 +770,9 @@ void Position::do_move(Move m, StateInfo& newSt, const CheckInfo& ci, bool moveI
Key k = st->key;
// Copy some fields of old state to our new StateInfo object except the ones
// which are recalculated from scratch anyway, then switch our state pointer
// to point to the new, ready to be updated, state.
memcpy(&newSt, st, sizeof(ReducedStateInfo));
// which are going to be recalculated from scratch anyway, then switch our state
// pointer to point to the new, ready to be updated, state.
memcpy(&newSt, st, StateCopySize64 * sizeof(uint64_t));
newSt.previous = st;
st = &newSt;