version 1.1.1.1, 2000/01/10 15:35:23 |
version 1.1.1.3, 2003/08/25 16:06:20 |
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/* popcount.c |
/* mpn_popcount -- mpn bit population count. |
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Copyright (C) 1994, 1996 Free Software Foundation, Inc. |
Copyright 1994, 1996, 2000, 2001 Free Software Foundation, Inc. |
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This file is part of the GNU MP Library. |
This file is part of the GNU MP Library. |
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The GNU MP Library is free software; you can redistribute it and/or modify |
The GNU MP Library is free software; you can redistribute it and/or modify |
it under the terms of the GNU Library General Public License as published by |
it under the terms of the GNU Lesser General Public License as published by |
the Free Software Foundation; either version 2 of the License, or (at your |
the Free Software Foundation; either version 2.1 of the License, or (at your |
option) any later version. |
option) any later version. |
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The GNU MP Library is distributed in the hope that it will be useful, but |
The GNU MP Library is distributed in the hope that it will be useful, but |
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public |
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
License for more details. |
License for more details. |
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You should have received a copy of the GNU Library General Public License |
You should have received a copy of the GNU Lesser General Public License |
along with the GNU MP Library; see the file COPYING.LIB. If not, write to |
along with the GNU MP Library; see the file COPYING.LIB. If not, write to |
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
MA 02111-1307, USA. */ |
MA 02111-1307, USA. */ |
Line 22 MA 02111-1307, USA. */ |
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Line 22 MA 02111-1307, USA. */ |
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#include "gmp.h" |
#include "gmp.h" |
#include "gmp-impl.h" |
#include "gmp-impl.h" |
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#if defined __GNUC__ |
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#if defined __sparc_v9__ && BITS_PER_MP_LIMB == 64 |
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#define popc_limb(a) \ |
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({ \ |
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DItype __res; \ |
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asm ("popc %1,%0" : "=r" (__res) : "rI" (a)); \ |
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__res; \ |
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}) |
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#endif |
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#endif |
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#ifndef popc_limb |
unsigned long |
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mpn_popcount (mp_srcptr p, mp_size_t size) |
/* Cool population count of a mp_limb_t. |
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You have to figure out how this works, I won't tell you! */ |
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static inline unsigned int |
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popc_limb (x) |
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mp_limb_t x; |
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{ |
{ |
#if BITS_PER_MP_LIMB == 64 |
unsigned long result = 0; |
/* We have to go into some trouble to define these constants. |
unsigned long n; |
(For mp_limb_t being `long long'.) */ |
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mp_limb_t cnst; |
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cnst = 0x55555555L | ((mp_limb_t) 0x55555555L << BITS_PER_MP_LIMB/2); |
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x = ((x & ~cnst) >> 1) + (x & cnst); |
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cnst = 0x33333333L | ((mp_limb_t) 0x33333333L << BITS_PER_MP_LIMB/2); |
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x = ((x & ~cnst) >> 2) + (x & cnst); |
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cnst = 0x0f0f0f0fL | ((mp_limb_t) 0x0f0f0f0fL << BITS_PER_MP_LIMB/2); |
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x = ((x >> 4) + x) & cnst; |
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x = ((x >> 8) + x); |
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x = ((x >> 16) + x); |
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x = ((x >> 32) + x) & 0xff; |
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#endif |
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#if BITS_PER_MP_LIMB == 32 |
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x = ((x >> 1) & 0x55555555L) + (x & 0x55555555L); |
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x = ((x >> 2) & 0x33333333L) + (x & 0x33333333L); |
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x = ((x >> 4) + x) & 0x0f0f0f0fL; |
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x = ((x >> 8) + x); |
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x = ((x >> 16) + x) & 0xff; |
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#endif |
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return x; |
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} |
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#endif |
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unsigned long int |
ASSERT (size >= 1); |
#if __STDC__ |
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mpn_popcount (register mp_srcptr p, register mp_size_t size) |
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#else |
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mpn_popcount (p, size) |
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register mp_srcptr p; |
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register mp_size_t size; |
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#endif |
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{ |
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unsigned long int popcnt; |
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mp_size_t i; |
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popcnt = 0; |
do { |
for (i = 0; i < size; i++) |
popc_limb (n, *p++); |
popcnt += popc_limb (p[i]); |
result += n; |
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} while (--size != 0); |
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return popcnt; |
return result; |
} |
} |