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/* @(#)s_ceil.c 5.1 93/09/24 */
/*
* ====================================================
* 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.
* ====================================================
*/
/*
* ceil(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-double.h>
#include <math-use-builtins.h>
double
__ceil (double x)
{
#if USE_CEIL_BUILTIN
return __builtin_ceil (x);
#else
/* Use generic implementation. */
int64_t i0, i;
int32_t j0;
EXTRACT_WORDS64 (i0, x);
j0 = ((i0 >> 52) & 0x7ff) - 0x3ff;
if (j0 <= 51)
{
if (j0 < 0)
{
/* return 0 * sign(x) if |x| < 1 */
if (i0 < 0)
i0 = INT64_C (0x8000000000000000);
else if (i0 != 0)
i0 = INT64_C (0x3ff0000000000000);
}
else
{
i = INT64_C (0x000fffffffffffff) >> j0;
if ((i0 & i) == 0)
return x; /* x is integral */
if (i0 > 0)
i0 += UINT64_C (0x0010000000000000) >> j0;
i0 &= ~i;
}
}
else
{
if (j0 == 0x400)
return x + x; /* inf or NaN */
else
return x; /* x is integral */
}
INSERT_WORDS64 (x, i0);
return x;
#endif /* ! USE_CEIL_BUILTIN */
}
#ifndef __ceil
libm_alias_double (__ceil, ceil)
#endif
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