From d9dc9dbd65263f8644afcc1fc632e9201ad20c70 Mon Sep 17 00:00:00 2001 From: Marco Costalba Date: Fri, 27 Aug 2010 12:15:07 +0200 Subject: [PATCH] Split branches in generate_piece_moves() Instead of one comparison in while() condition use two, the first to check if the piece is exsistant and the second to loop across pieces of that type. This should help branch prediction in cases we have only one piece of the same type, for instance for queens, the first branch is always true and the second is almost always false. Increased speed of 0.3-0.5 % on Gcc pgo compiles. No functional change. Signed-off-by: Marco Costalba --- src/movegen.cpp | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/src/movegen.cpp b/src/movegen.cpp index 0598249d..ea3255cc 100644 --- a/src/movegen.cpp +++ b/src/movegen.cpp @@ -429,10 +429,13 @@ namespace { Square from; const Square* ptr = pos.piece_list_begin(us, Piece); - while ((from = *ptr++) != SQ_NONE) + if (*ptr != SQ_NONE) { - b = pos.attacks_from(from) & target; - SERIALIZE_MOVES(b); + do { + from = *ptr; + b = pos.attacks_from(from) & target; + SERIALIZE_MOVES(b); + } while (*++ptr != SQ_NONE); } return mlist; } -- 2.39.2