62 lines
1.4 KiB
C++
62 lines
1.4 KiB
C++
// include/ffs.hh
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// This file is part of libpbe; see http://svn.chezphil.org/libpbe/
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// (C) 2007 Philip Endecott
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// This program is free software; you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation; either version 2 of the License, or
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// any later version.
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//
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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#ifndef pbe_ffs_hh
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#define pbe_ffs_hh
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// ffs - Find First Set
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// This is overloading of the libc ffs* functions for different int types.
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// Find the least significant bit set in a value and return its index.
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// Bits are numbered starting from 1.
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// If no bits are set, return 0.
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#ifndef _GNU_SOURCE
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#define _GNU_SOURCE
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#include <string.h>
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#undef _GNU_SOURCE
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#else
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#include <string.h>
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#endif
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#include <boost/cstdint.hpp>
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namespace pbe {
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inline int ffs(::uint32_t i) {
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return ::ffsl(i);
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}
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inline int ffs(::int32_t i) {
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return ::ffsl(i);
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}
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inline int ffs(::uint64_t i) {
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return ::ffsll(i);
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}
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inline int ffs(::int64_t i) {
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return ::ffsll(i);
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}
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};
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#endif
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