X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fbitboard.cpp;h=64cba6b5fc301322299a0eb3cf0d8c5102b07867;hb=46a50cbf38bdfa5e48358585f4c98668507700ae;hp=84e576c62d1577a3615e4e11f465ae8bb3d82c45;hpb=3b906ffc2765856948f1baac5ceb5209fe4380e2;p=stockfish

diff --git a/src/bitboard.cpp b/src/bitboard.cpp
index 84e576c6..64cba6b5 100644
--- a/src/bitboard.cpp
+++ b/src/bitboard.cpp
@@ -138,8 +138,32 @@ Square pop_1st_bit(Bitboard* b) {
    return Square(BSFTable[((~(u.b.h ^ (u.b.h - 1))) * 0x783A9B23) >> 26]);
 }
 
-#endif // !defined(USE_BSFQ)
+Square last_1(Bitboard b) {
+
+  int result = 0;
+
+  if (b > 0xFFFFFFFF)
+  {
+      b >>= 32;
+      result = 32;
+  }
+
+  if (b > 0xFFFF)
+  {
+      b >>= 16;
+      result += 16;
+  }
+
+  if (b > 0xFF)
+  {
+      b >>= 8;
+      result += 8;
+  }
 
+  return Square(result + BitCount8Bit[b]);
+}
+
+#endif // !defined(USE_BSFQ)
 
 /// bitboards_init() initializes various bitboard arrays. It is called during
 /// program initialization.