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/* s_floorf.c -- float version of s_floor.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
/*
* floorf(x)
* Return x rounded toward -inf to integral value
* Method:
* Bit twiddling.
*/
#define NO_MATH_REDIRECT
#include <math.h>
#include <math_private.h>
#include <libm-alias-float.h>
#include <math-use-builtins.h>
float
__floorf (float x)
{
#if USE_FLOORF_BUILTIN
return __builtin_floorf (x);
#else
/* Use generic implementation. */
int32_t i0, j0;
uint32_t i;
GET_FLOAT_WORD (i0, x);
j0 = ((i0 >> 23) & 0xff) - 0x7f;
if (j0 < 23)
{
if (j0 < 0)
{
/* return 0 * sign (x) if |x| < 1 */
if (i0 >= 0)
i0 = 0;
else if ((i0 & 0x7fffffff) != 0)
i0 = 0xbf800000;
}
else
{
i = (0x007fffff) >> j0;
if ((i0 & i) == 0)
return x; /* x is integral */
if (i0 < 0)
i0 += (0x00800000) >> j0;
i0 &= (~i);
}
}
else
{
if (__glibc_unlikely (j0 == 0x80))
return x + x; /* inf or NaN */
else
return x; /* x is integral */
}
SET_FLOAT_WORD (x, i0);
return x;
#endif /* ! USE_FLOORF_BUILTIN */
}
#ifndef __floorf
libm_alias_float (__floor, floor)
#endif
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