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Restore correct 64 bit version of pop_1st_bit()

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Was erroneusly changed with the 32bit in recent
patch "Retire USE_COMPACT_ROOK_ATTACKS...".

Also another clean up of define magics. Move compiler
specific definitions in types.h and remove redundant cruft.

Now this macro ugly mess seems more reasonable.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This commit is contained in:
Marco Costalba
2009-07-03 08:40:41 +01:00
parent a87ea9846d
commit 5d79af9e0d
4 changed files with 65 additions and 91 deletions
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62
src/bitcount.h
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@@ -28,29 +28,7 @@
//#define DISABLE_POPCNT_SUPPORT
#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
#include "types.h"
// Select type of intrinsic bit count instruction to use
@@ -86,24 +64,29 @@ inline bool cpu_has_popcnt() { return false; }
#define POPCNT_INTRINSIC(x) count_1s(x)
#endif
#endif // cpu_has_popcnt() selection
/// Software implementation of bit count functions
#if defined(BITCOUNT_LOOP)
#if defined(IS_64BIT)
inline int count_1s(Bitboard b) {
int r;
for(r = 0; b; r++, b &= b - 1);
return r;
b -= ((b>>1) & 0x5555555555555555ULL);
b = ((b>>2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL);
b = ((b>>4) + b) & 0x0F0F0F0F0F0F0F0FULL;
b *= 0x0101010101010101ULL;
return int(b >> 56);
}
inline int count_1s_max_15(Bitboard b) {
return count_1s(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 count_1s(Bitboard b) {
unsigned w = unsigned(b >> 32), v = unsigned(b);
@@ -128,23 +111,6 @@ inline int count_1s_max_15(Bitboard b) {
return int(v >> 28);
}
#elif defined(BITCOUNT_SWAR_64)
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 count_1s_max_15(Bitboard b) {
b -= (b>>1) & 0x5555555555555555ULL;
b = ((b>>2) & 0x3333333333333333ULL) + (b & 0x3333333333333333ULL);
b *= 0x1111111111111111ULL;
return int(b >> 60);
}
#endif // BITCOUNT
@@ -177,7 +143,7 @@ const bool CpuHasPOPCNT = cpu_has_popcnt();
// 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)
#if defined(IS_64BIT)
const bool CpuHas64BitPath = true;
#else
const bool CpuHas64BitPath = false;