X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitcount.h;h=63d7704b91edbb85643def092c194eeb468151bc;hp=c6e969a82411d4b37dc1633e512ca5873d4a2912;hb=66b751713e1785cc4ae1779318ae2fdafa734add;hpb=ce5d9eb19da890c77d8ef00e078c60edc3e8e4aa diff --git a/src/bitcount.h b/src/bitcount.h index c6e969a8..63d7704b 100644 --- a/src/bitcount.h +++ b/src/bitcount.h @@ -1,7 +1,7 @@ /* 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 @@ -22,90 +22,46 @@ #if !defined(BITCOUNT_H_INCLUDED) #define BITCOUNT_H_INCLUDED -// To disable POPCNT support uncomment following line. You should do it only -// in PGO compiling to exercise the default fallback path. Don't forget to -// re-comment the line for the final optimized compile though ;-) -//#define DISABLE_POPCNT_SUPPORT +#include "types.h" +// Select type of intrinsic bit count instruction to use, see +// README.txt on how to pgo compile with POPCNT support. +#if !defined(USE_POPCNT) +#define POPCNT_INTRINSIC(x) 0 +#elif defined(_MSC_VER) +#define POPCNT_INTRINSIC(x) (int)__popcnt64(x) +#elif defined(__GNUC__) -#include "bitboard.h" - - -// Select type of software bit count function to use - -#if !defined(AUTO_CONFIGURATION) || defined(IS_64BIT) - -//#define USE_COMPACT_ROOK_ATTACKS -//#define USE_32BIT_ATTACKS -#define USE_FOLDED_BITSCAN - -#define BITCOUNT_SWAR_64 -//#define BITCOUNT_SWAR_32 -//#define BITCOUNT_LOOP - -#else - -#define USE_32BIT_ATTACKS -#define USE_FOLDED_BITSCAN -#define BITCOUNT_SWAR_32 - -#endif - - -// Select type of intrinsic bit count instruction to use - -#if defined(_MSC_VER) && defined(_WIN64) // Microsoft compiler - -#include - -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(__INTEL_COMPILER) && (defined(__x86_64) || defined(_M_X64)) // Intel compiler - -#include - -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) - -#else // Safe fallback for unsupported compilers - -inline bool cpu_has_popcnt() { return false; } - -#define POPCNT_INTRINSIC(x) sw_count_1s(x) +#define POPCNT_INTRINSIC(x) ({ \ + unsigned long __ret; \ + __asm__("popcnt %1, %0" : "=r" (__ret) : "r" (x)); \ + __ret; }) #endif /// Software implementation of bit count functions -#if defined(BITCOUNT_LOOP) +#if defined(IS_64BIT) -inline int sw_count_1s(Bitboard b) { - int r; - for(r = 0; b; r++, b &= b - 1); - return r; +inline int count_1s(Bitboard b) { + b -= ((b>>1) & 0x5555555555555555ULL); + b = ((b>>2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL); + b = ((b>>4) + b) & 0x0F0F0F0F0F0F0F0FULL; + b *= 0x0101010101010101ULL; + return int(b >> 56); } -inline int sw_count_1s_max_15(Bitboard b) { - return count_1s(b); +inline int count_1s_max_15(Bitboard b) { + b -= (b>>1) & 0x5555555555555555ULL; + b = ((b>>2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL); + b *= 0x1111111111111111ULL; + return int(b >> 60); } -#elif defined(BITCOUNT_SWAR_32) +#else // if !defined(IS_64BIT) -inline int sw_count_1s(Bitboard b) { +inline int count_1s(Bitboard b) { unsigned w = unsigned(b >> 32), v = unsigned(b); v -= (v >> 1) & 0x55555555; // 0-2 in 2 bits w -= (w >> 1) & 0x55555555; @@ -117,7 +73,7 @@ inline int sw_count_1s(Bitboard b) { return int(v >> 24); } -inline int sw_count_1s_max_15(Bitboard b) { +inline int count_1s_max_15(Bitboard b) { unsigned w = unsigned(b >> 32), v = unsigned(b); v -= (v >> 1) & 0x55555555; // 0-2 in 2 bits w -= (w >> 1) & 0x55555555; @@ -128,23 +84,6 @@ inline int sw_count_1s_max_15(Bitboard b) { return int(v >> 28); } -#elif defined(BITCOUNT_SWAR_64) - -inline int sw_count_1s(Bitboard b) { - b -= ((b>>1) & 0x5555555555555555ULL); - b = ((b>>2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL); - b = ((b>>4) + b) & 0x0F0F0F0F0F0F0F0FULL; - b *= 0x0101010101010101ULL; - return int(b >> 56); -} - -inline int sw_count_1s_max_15(Bitboard b) { - b -= (b>>1) & 0x5555555555555555ULL; - b = ((b>>2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL); - b *= 0x1111111111111111ULL; - return int(b >> 60); -} - #endif // BITCOUNT @@ -155,29 +94,38 @@ inline int sw_count_1s_max_15(Bitboard b) { template inline int count_1s(Bitboard b) { - return UseIntrinsic ? POPCNT_INTRINSIC(b) : sw_count_1s(b); + return UseIntrinsic ? POPCNT_INTRINSIC(b) : count_1s(b); } template inline int count_1s_max_15(Bitboard b) { - return UseIntrinsic ? POPCNT_INTRINSIC(b) : sw_count_1s_max_15(b); + return UseIntrinsic ? POPCNT_INTRINSIC(b) : count_1s_max_15(b); +} + + +// Detect hardware POPCNT support +inline bool cpu_has_popcnt() { + + int CPUInfo[4] = {-1}; + __cpuid(CPUInfo, 0x00000001); + return (CPUInfo[2] >> 23) & 1; } -// Global variable initialized at startup that is set to true if +// Global constant initialized at startup that is set to true if // CPU on which application runs supports POPCNT intrinsic. Unless -// DISABLE_POPCNT_SUPPORT is defined. -#if defined(DISABLE_POPCNT_SUPPORT) -const bool CpuHasPOPCNT = false; -#else +// USE_POPCNT is not defined. +#if defined(USE_POPCNT) const bool CpuHasPOPCNT = cpu_has_popcnt(); +#else +const bool CpuHasPOPCNT = false; #endif -// Global variable used to print info about the use of 64 optimized -// functions to verify that a 64bit compile has been correctly built. -#if defined(BITCOUNT_SWAR_64) +// Global constant used to print info about the use of 64 optimized +// functions to verify that a 64 bit compile has been correctly built. +#if defined(IS_64BIT) const bool CpuHas64BitPath = true; #else const bool CpuHas64BitPath = false;