X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Ftt.cpp;h=e140a0ba10ec5fa2183b506b68750a4dcbc39289;hp=ffb8b0124568e58101a913af300b60bf2dc195ce;hb=e33c94883fb1767a8aae29e8004d0621d296e33b;hpb=8d369600eca3fe3d059cfa8ba68d74ccdd883e33

diff --git a/src/tt.cpp b/src/tt.cpp
index ffb8b012..e140a0ba 100644
--- a/src/tt.cpp
+++ b/src/tt.cpp
@@ -25,17 +25,11 @@
 #include <cassert>
 #include <cmath>
 #include <cstring>
+#include <xmmintrin.h>
 
 #include "movegen.h"
 #include "tt.h"
 
-#if defined(_MSC_VER)
-#include <xmmintrin.h>
-#endif
-
-// This is the number of TTEntry slots for each position
-static const int ClusterSize = 4;
-
 // The main transposition table
 TranspositionTable TT;
 
@@ -67,14 +61,14 @@ void TranspositionTable::set_size(unsigned mbSize) {
 
   // We store a cluster of ClusterSize number of TTEntry for each position
   // and newSize is the maximum number of storable positions.
-  while ((2 * newSize) * ClusterSize * (sizeof(TTEntry)) <= (mbSize << 20))
+  while ((2 * newSize) * sizeof(TTCluster) <= (mbSize << 20))
       newSize *= 2;
 
   if (newSize != size)
   {
       size = newSize;
       delete [] entries;
-      entries = new TTEntry[size * ClusterSize];
+      entries = new TTCluster[size];
       if (!entries)
       {
           std::cerr << "Failed to allocate " << mbSize
@@ -93,7 +87,7 @@ void TranspositionTable::set_size(unsigned mbSize) {
 
 void TranspositionTable::clear() {
 
-  memset(entries, 0, size * ClusterSize * sizeof(TTEntry));
+  memset(entries, 0, size * sizeof(TTCluster));
 }
 
 
@@ -103,7 +97,7 @@ void TranspositionTable::clear() {
 
 inline TTEntry* TranspositionTable::first_entry(const Key posKey) const {
 
-  return entries + ((uint32_t(posKey) & (size - 1)) * ClusterSize);
+  return entries[uint32_t(posKey) & (size - 1)].data;
 }
 
 
@@ -178,16 +172,15 @@ TTEntry* TranspositionTable::retrieve(const Key posKey) const {
 
 void TranspositionTable::prefetch(const Key posKey) const {
 
-#if defined(_MSC_VER)
-   char* addr = (char*)first_entry(posKey);
-  _mm_prefetch(addr, _MM_HINT_T0);
-  _mm_prefetch(addr+64, _MM_HINT_T0);
-#else
-  // We need to force an asm volatile here because gcc builtin
-  // is optimized away by Intel compiler.
-  char* addr = (char*)first_entry(posKey);
-  asm volatile("prefetcht0 %0" :: "m" (addr));
+#if defined(__INTEL_COMPILER) || defined(__ICL)
+   // This hack prevents prefetches to be optimized away by the
+   // Intel compiler. Both MSVC and gcc seems not affected.
+   __asm__ ("");
 #endif
+
+   char const* addr = (char*)first_entry(posKey);
+  _mm_prefetch(addr, _MM_HINT_T2);
+  _mm_prefetch(addr+64, _MM_HINT_T2); // 64 bytes ahead
 }