X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.cpp;h=7d86884d12ee51caab40e70e1b14eac56b3f019c;hp=9bd16d2f66a96e60be496258ea550fc6bcb6277a;hb=4d9e9ac3d45190f4d92030fe9de2637344018f0a;hpb=080a4995a3977a0fe7071e62151dc4d716a13302

diff --git a/src/bitboard.cpp b/src/bitboard.cpp
index 9bd16d2f..7d86884d 100644
--- a/src/bitboard.cpp
+++ b/src/bitboard.cpp
@@ -297,6 +297,7 @@ void init_bitboards() {
 
 #if defined(IS_64BIT) && !defined(USE_BSFQ)
 
+CACHE_LINE_ALIGNMENT
 static const int BitTable[64] = {
   0, 1, 2, 7, 3, 13, 8, 19, 4, 25, 14, 28, 9, 34, 20, 40, 5, 17, 26, 38, 15,
   46, 29, 48, 10, 31, 35, 54, 21, 50, 41, 57, 63, 6, 12, 18, 24, 27, 33, 39,
@@ -316,7 +317,8 @@ Square pop_1st_bit(Bitboard* b) {
 
 #elif !defined(USE_BSFQ)
 
-static const int BitTable[64] = {
+static CACHE_LINE_ALIGNMENT
+const int BitTable[64] = {
   63, 30, 3, 32, 25, 41, 22, 33, 15, 50, 42, 13, 11, 53, 19, 34, 61, 29, 2,
   51, 21, 43, 45, 10, 18, 47, 1, 54, 9, 57, 0, 35, 62, 31, 40, 4, 49, 5, 52,
   26, 60, 6, 23, 44, 46, 27, 56, 16, 7, 39, 48, 24, 59, 14, 12, 55, 38, 28,
@@ -334,36 +336,59 @@ union b_union {
 
     Bitboard b;
     struct {
+#if defined (BIGENDIAN)
+        uint32_t h;
+        uint32_t l;
+#else
         uint32_t l;
         uint32_t h;
+#endif
     } dw;
 };
 
-// WARNING: Needs -fno-strict-aliasing compiler option
 Square pop_1st_bit(Bitboard* bb) {
 
-  b_union u;
-  uint32_t b;
+   b_union* u;
+   Square ret;
 
-  u.b = *bb;
+   u = (b_union*)bb;
 
-  if (u.dw.l)
-  {
-      b = u.dw.l;
-      *((uint32_t*)bb) = b & (b - 1);
-      b ^= (b - 1);
-  }
-  else
-  {
-      b = u.dw.h;
-      *((uint32_t*)bb+1) = b & (b - 1); // Little endian only?
-      b = ~(b ^ (b - 1));
-  }
-  return Square(BitTable[(b * 0x783a9b23) >> 26]);
+   if (u->dw.l)
+   {
+       ret = Square(BitTable[((u->dw.l ^ (u->dw.l - 1)) * 0x783a9b23) >> 26]);
+       u->dw.l &= (u->dw.l - 1);
+       return ret;
+   }
+   ret = Square(BitTable[((~(u->dw.h ^ (u->dw.h - 1))) * 0x783a9b23) >> 26]);
+   u->dw.h &= (u->dw.h - 1);
+   return ret;
 }
 
 #endif
 
+int bitScanReverse32(uint32_t b)
+{
+   int result = 0;
+
+   if (b > 0xFFFF) {
+      b >>= 16;
+      result += 16;
+   }
+   if (b > 0xFF) {
+      b >>= 8;
+      result += 8;
+   }
+   if (b > 0xF) {
+      b >>= 4;
+      result += 4;
+   }
+   if (b > 0x3) {
+      b >>= 2;
+      result += 2;
+   }
+   return result + (b > 0) + (b > 1);
+}
+
 namespace {
 
   // All functions below are used to precompute various bitboards during