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#pragma once
/*
* Copyright (C) 2005-2008 Team XBMC
* http://www.xbmc.org
*
* This Program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This Program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with XBMC; see the file COPYING. If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
* http://www.gnu.org/copyleft/gpl.html
*
*/
#include <cassert>
#include <climits>
#include <cmath>
namespace MathUtils
{
// GCC does something stupid with optimization on release builds if we try
// to assert in these functions
inline int round_int (double x)
{
assert(x > static_cast<double>(INT_MIN / 2) - 1.0);
assert(x < static_cast <double>(INT_MAX / 2) + 1.0);
const float round_to_nearest = 0.5f;
int i;
#ifndef _LINUX
__asm
{
fld x
fadd st, st (0)
fadd round_to_nearest
fistp i
sar i, 1
}
#else
#if defined(__powerpc__) || defined(__ppc__)
i = floor(x + round_to_nearest);
#else
__asm__ __volatile__ (
"fadd %%st\n\t"
"fadd %%st(1)\n\t"
"fistpl %0\n\t"
"sarl $1, %0\n"
: "=m"(i) : "u"(round_to_nearest), "t"(x) : "st"
);
#endif
#endif
return (i);
}
inline int ceil_int (double x)
{
assert(x > static_cast<double>(INT_MIN / 2) - 1.0);
assert(x < static_cast <double>(INT_MAX / 2) + 1.0);
#if !defined(__powerpc__) && !defined(__ppc__)
const float round_towards_p_i = -0.5f;
#endif
int i;
#ifndef _LINUX
__asm
{
fld x
fadd st, st (0)
fsubr round_towards_p_i
fistp i
sar i, 1
}
#else
#if defined(__powerpc__) || defined(__ppc__)
return (int)ceil(x);
#else
__asm__ __volatile__ (
"fadd %%st\n\t"
"fsubr %%st(1)\n\t"
"fistpl %0\n\t"
"sarl $1, %0\n"
: "=m"(i) : "u"(round_towards_p_i), "t"(x) : "st"
);
#endif
#endif
return (-i);
}
inline int truncate_int(double x)
{
assert(x > static_cast<double>(INT_MIN / 2) - 1.0);
assert(x < static_cast <double>(INT_MAX / 2) + 1.0);
#if !defined(__powerpc__) && !defined(__ppc__)
const float round_towards_m_i = -0.5f;
#endif
int i;
#ifndef _LINUX
__asm
{
fld x
fadd st, st (0)
fabs
fadd round_towards_m_i
fistp i
sar i, 1
}
#else
#if defined(__powerpc__) || defined(__ppc__)
return (int)x;
#else
__asm__ __volatile__ (
"fadd %%st\n\t"
"fabs\n\t"
"fadd %%st(1)\n\t"
"fistpl %0\n\t"
"sarl $1, %0\n"
: "=m"(i) : "u"(round_towards_m_i), "t"(x) : "st"
);
#endif
#endif
if (x < 0)
i = -i;
return (i);
}
inline void hack()
{
// stupid hack to keep compiler from dropping these
// functions as unused
MathUtils::round_int(0.0);
MathUtils::truncate_int(0.0);
MathUtils::ceil_int(0.0);
}
} // namespace MathUtils
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