34 lines
1.1 KiB
C
34 lines
1.1 KiB
C
/*
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* This file is part of ltrace.
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* Copyright (C) 2013 Petr Machata, Red Hat Inc.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of the
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* License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
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* 02110-1301 USA
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*/
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#include "bits.h"
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/* This is called rarely, and any overhead will be lost in ptrace
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* noise, so the algorithm doesn't need to be terribly clever. For
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* the same reason we don't bother defining the corresponding _32
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* variant. */
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unsigned
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bitcount(uint64_t u)
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{
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int c = 0;
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for (; u > 0; u &= u - 1)
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c++;
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return c;
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}
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