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/* EINA - EFL data type library
* Copyright (C) 2007-2009 Jorge Luis Zapata Muga, Cedric BAIL
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library;
* if not, see <http://www.gnu.org/licenses/>.
*/
#ifndef EINA_INLINE_F32P32_X_
# define EINA_INLINE_F32P32_X_
#include <stdlib.h>
static inline Eina_F32p32
eina_f32p32_add(Eina_F32p32 a, Eina_F32p32 b)
{
return a + b;
}
static inline Eina_F32p32
eina_f32p32_sub(Eina_F32p32 a, Eina_F32p32 b)
{
return a - b;
}
static inline Eina_F32p32
eina_f32p32_mul(Eina_F32p32 a, Eina_F32p32 b)
{
/* To prevent overflow during multiplication
* we need to reduce the precision of the fraction part
* Shift both values to only contain 16 bit of the fraction part
* (rounded).
* After multiplication we again have a value with a 32-bit
* fraction part. See also
* http://en.wikipedia.org/wiki/Fixed-point_arithmetic#Operations
*/
Eina_F32p32 up;
Eina_F32p32 result;
uint64_t as, bs;
Eina_F32p32 sign;
sign = a ^ b;
as = eina_fp32p32_llabs(a);
bs = eina_fp32p32_llabs(b);
/* Reduce fraction to 16-bit (rounded) */
as = (as >> 16) + ((as >> 15) & 0x1);
bs = (bs >> 16) + ((bs >> 15) & 0x1);
up = as * bs;
result = up;
return sign < 0 ? - result : result;
}
static inline Eina_F32p32
eina_f32p32_scale(Eina_F32p32 a, int b)
{
return a * b;
}
static inline Eina_F32p32
eina_f32p32_div(Eina_F32p32 a, Eina_F32p32 b)
{
Eina_F32p32 sign;
Eina_F32p32 result;
sign = a ^ b;
/* FIXME: This should probably map to +/-inf when converting to double
or we should abort... */
if (b == 0)
return sign < 0 ? (Eina_F32p32) 0x8000000000000000ull : (Eina_F32p32) 0x7FFFFFFFFFFFFFFFull;
result = (eina_f32p32_mul(eina_fp32p32_llabs(a), (((uint64_t) 1 << 62) / ((uint64_t)(eina_fp32p32_llabs(b)) >> 2))));
return sign < 0 ? - result : result;
}
static inline Eina_F32p32
eina_f32p32_sqrt(Eina_F32p32 a)
{
uint64_t root, remHi, remLo, testDiv, count;
root = 0; /* Clear root */
remHi = 0; /* Clear high part of partial remainder */
remLo = a; /* Get argument into low part of partial remainder */
count = (31 + (32 >> 1)); /* Load loop counter */
do {
remHi = (remHi << 2) | (remLo >> 30);
remLo <<= 2; /* get 2 bits of arg */
root <<= 1; /* Get ready for the next bit in the root */
testDiv = (root << 1) + 1; /* Test radical */
if (remHi >= testDiv) {
remHi -= testDiv;
root++;
}
} while (count-- != 0);
return root;
}
static inline unsigned int
eina_f32p32_fracc_get(Eina_F32p32 v)
{
return (unsigned int)v;
}
#endif
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