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/*
* This file is part of the libpayload project.
*
* Copyright 2015 Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <libpayload.h>
/*
* Provide platform-independent backend implementation for __builtin_clz() in
* <libpayload.h> in case GCC does not have an assembly version for this arch.
*/
int __clzsi2(u32 a);
int __clzsi2(u32 a)
{
static const u8 four_bit_table[] = {
[0x0] = 4, [0x1] = 3, [0x2] = 2, [0x3] = 2,
[0x4] = 1, [0x5] = 1, [0x6] = 1, [0x7] = 1,
[0x8] = 0, [0x9] = 0, [0xa] = 0, [0xb] = 0,
[0xc] = 0, [0xd] = 0, [0xe] = 0, [0xf] = 0,
};
int r = 0;
if (!(a & (0xffff << 16))) {
r += 16;
a <<= 16;
}
if (!(a & (0xff << 24))) {
r += 8;
a <<= 8;
}
if (!(a & (0xf << 28))) {
r += 4;
a <<= 4;
}
return r + four_bit_table[a >> 28];
}
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