Fix POPCNT support for Intel compiler under Windows

mcostalba · mcostalba · commit 761450136289 · 2011-01-05T21:12:19.000+01:00
Reported by Martin Wyngaarden that also confirmed
this patch to work.

No functional change.

Signed-off-by: Marco Costalba &lt;mcostalba@gmail.com&gt;
diff --git a/src/bitcount.h b/src/bitcount.h
@@ -85,6 +85,8 @@ template<>
 inline int count_1s<CNT_POPCNT>(Bitboard b) {
 #if !defined(USE_POPCNT)
   return int(b != 0); // Avoid 'b not used' warning
+#elif defined(_MSC_VER) && defined(__INTEL_COMPILER)
+  return _mm_popcnt_u64(b);
 #elif defined(_MSC_VER)
   return __popcnt64(b);
 #elif defined(__GNUC__)
diff --git a/src/types.h b/src/types.h
@@ -86,6 +86,11 @@ typedef uint64_t Bitboard;
 #define USE_BSFQ
 #endif
 
+// Intel header for _mm_popcnt_u64() intrinsic
+#if defined(USE_POPCNT) && defined(_MSC_VER) && defined(__INTEL_COMPILER)
+#include <nmmintrin.h>
+#endif
+
 // Cache line alignment specification
 #if defined(_MSC_VER) || defined(__INTEL_COMPILER)
 #define CACHE_LINE_ALIGNMENT __declspec(align(64))
