2012-03-21 08:44:43 +01:00
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/*
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2018-10-31 17:54:59 +01:00
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* Copyright 2003-2018 The Music Player Daemon Project
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2012-03-21 08:44:43 +01:00
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* http://www.musicpd.org
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*
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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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* (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,
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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 along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
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#include "bit_reverse.h"
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/**
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* @see http://graphics.stanford.edu/~seander/bithacks.html#BitReverseTable
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*/
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const uint8_t bit_reverse_table[256] =
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{
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#define R2(n) n, n + 2*64, n + 1*64, n + 3*64
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#define R4(n) R2(n), R2(n + 2*16), R2(n + 1*16), R2(n + 3*16)
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#define R6(n) R4(n), R4(n + 2*4 ), R4(n + 1*4 ), R4(n + 3*4 )
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R6(0), R6(2), R6(1), R6(3)
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};
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