mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-03 04:01:43 +08:00
62560ee840
This patch is using the corresponding GCC builtin for ceilf, ceil, ceill and ceilf128 if the USE_FUNCTION_BUILTIN macros are defined to one in math-use-builtins.h. This is the case for s390 if build with at least --march=z196 --mzarch. Otherwise the generic implementation is used. The code of the generic implementation is not changed. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
71 lines
1.5 KiB
C
71 lines
1.5 KiB
C
/* @(#)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
|