/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2009 Marco Costalba
+ Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
// Select type of intrinsic bit count instruction to use, see
// README.txt on how to pgo compile with POPCNT support.
-
-#if defined(__INTEL_COMPILER) && defined(USE_POPCNT) // Intel compiler
-
-#include <nmmintrin.h>
-
-inline bool cpu_has_popcnt() {
-
- int CPUInfo[4] = {-1};
- __cpuid(CPUInfo, 0x00000001);
- return (CPUInfo[2] >> 23) & 1;
-}
-
-#define POPCNT_INTRINSIC(x) _mm_popcnt_u64(x)
-
-#elif defined(_MSC_VER) && defined(USE_POPCNT) // Microsoft compiler
-
-#include <intrin.h>
-
-inline bool cpu_has_popcnt() {
-
- int CPUInfo[4] = {-1};
- __cpuid(CPUInfo, 0x00000001);
- return (CPUInfo[2] >> 23) & 1;
-}
-
-#define POPCNT_INTRINSIC(x) __popcnt64(x)
-
-#elif defined(__GNUC__) && defined(USE_POPCNT) // Gcc compiler
-
-inline void __cpuid(unsigned int op,
- unsigned int *eax, unsigned int *ebx,
- unsigned int *ecx, unsigned int *edx)
-{
- *eax = op;
- *ecx = 0;
- __asm__("cpuid" : "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx)
- : "0" (*eax), "2" (*ecx));
-}
-
-inline bool cpu_has_popcnt() {
-
- unsigned int eax, ebx, ecx, edx;
- __cpuid(1, &eax, &ebx, &ecx, &edx);
- return (ecx >> 23) & 1;
-}
+#if !defined(USE_POPCNT)
+#define POPCNT_INTRINSIC(x) 0
+#elif defined(_MSC_VER)
+#define POPCNT_INTRINSIC(x) (int)__popcnt64(x)
+#elif defined(__GNUC__)
#define POPCNT_INTRINSIC(x) ({ \
unsigned long __ret; \
__asm__("popcnt %1, %0" : "=r" (__ret) : "r" (x)); \
__ret; })
-#else // Safe fallback for unsupported compilers or when USE_POPCNT is disabled
-
-inline bool cpu_has_popcnt() { return false; }
-
-#define POPCNT_INTRINSIC(x) 0
-
-#endif // cpu_has_popcnt() and POPCNT_INTRINSIC() definitions
+#endif
/// Software implementation of bit count functions
}
+// Detect hardware POPCNT support
+inline bool cpu_has_popcnt() {
+
+ int CPUInfo[4] = {-1};
+ __cpuid(CPUInfo, 0x00000001);
+ return (CPUInfo[2] >> 23) & 1;
+}
+
+
// Global constant initialized at startup that is set to true if
// CPU on which application runs supports POPCNT intrinsic. Unless
// USE_POPCNT is not defined.
+#if defined(USE_POPCNT)
const bool CpuHasPOPCNT = cpu_has_popcnt();
+#else
+const bool CpuHasPOPCNT = false;
+#endif
// Global constant used to print info about the use of 64 optimized