Implement and document ceill().

This commit is contained in:
Stefan Farfeleder 2005-01-13 09:11:41 +00:00
parent 4067ee86a5
commit 43295fac79
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=140172
4 changed files with 117 additions and 8 deletions

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@ -80,8 +80,9 @@ COMMON_SRCS= b_exp.c b_log.c b_tgamma.c \
e_sinh.c e_sinhf.c e_sqrt.c e_sqrtf.c fenv.c \
k_cos.c k_cosf.c k_rem_pio2.c k_rem_pio2f.c k_sin.c k_sinf.c \
k_standard.c k_tan.c k_tanf.c \
s_asinh.c s_asinhf.c s_atan.c s_atanf.c s_cbrt.c s_cbrtf.c s_ceil.c \
s_ceilf.c s_copysign.c s_copysignf.c s_cos.c s_cosf.c s_erf.c s_erff.c \
s_asinh.c s_asinhf.c s_atan.c s_atanf.c s_cbrt.c s_cbrtf.c \
s_ceil.c s_ceilf.c s_ceill.c \
s_copysign.c s_copysignf.c s_cos.c s_cosf.c s_erf.c s_erff.c \
s_expm1.c s_expm1f.c s_fabsf.c s_fdim.c s_finite.c s_finitef.c \
s_floor.c s_floorf.c s_floorl.c s_fmax.c s_fmaxf.c s_fmaxl.c s_fmin.c \
s_fminf.c s_fminl.c s_frexp.c s_frexpf.c s_ilogb.c s_ilogbf.c \
@ -143,7 +144,7 @@ MLINKS+=asinh.3 asinhf.3
MLINKS+=atan.3 atanf.3
MLINKS+=atanh.3 atanhf.3
MLINKS+=atan2.3 atan2f.3
MLINKS+=ceil.3 ceilf.3
MLINKS+=ceil.3 ceilf.3 ceil.3 ceill.3
MLINKS+=cimag.3 cimagf.3 cimag.3 cimagl.3 \
cimag.3 conj.3 cimag.3 conjf.3 cimag.3 conjl.3 \
cimag.3 creal.3 cimag.3 crealf.3 cimag.3 creall.3

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@ -32,12 +32,13 @@
.\" from: @(#)ceil.3 5.1 (Berkeley) 5/2/91
.\" $FreeBSD$
.\"
.Dd March 10, 1994
.Dd January 13, 2005
.Dt CEIL 3
.Os
.Sh NAME
.Nm ceil ,
.Nm ceilf
.Nm ceilf ,
.Nm ceill
.Nd smallest integral value greater than or equal to x
.Sh LIBRARY
.Lb libm
@ -47,11 +48,15 @@
.Fn ceil "double x"
.Ft float
.Fn ceilf "float x"
.Ft long double
.Fn ceill "long double x"
.Sh DESCRIPTION
The
.Fn ceil
and the
.Fn ceil ,
the
.Fn ceilf
and the
.Fn ceill
functions return the smallest integral value
greater than or equal to
.Fa x ,
@ -70,3 +75,9 @@ The
.Fn ceil
function conforms to
.St -isoC .
The
.Fn ceilf
and the
.Fn ceill
functions conform to
.St -isoC-99 .

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@ -431,8 +431,8 @@ long double atan2l(long double, long double);
long double atanhl(long double);
long double atanl(long double);
long double cbrtl(long double);
long double ceill(long double);
#endif
long double ceill(long double);
long double copysignl(long double, long double);
#if 0
long double coshl(long double);

97
lib/msun/src/s_ceill.c Normal file
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@ -0,0 +1,97 @@
/*
* ====================================================
* 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.
* ====================================================
*
* From: @(#)s_ceil.c 5.1 93/09/24
*/
#ifndef lint
static char rcsid[] = "$FreeBSD$";
#endif
/*
* ceill(x)
* Return x rounded toward -inf to integral value
* Method:
* Bit twiddling.
* Exception:
* Inexact flag raised if x not equal to ceill(x).
*/
#include <float.h>
#include <math.h>
#include <stdint.h>
#include "fpmath.h"
#ifdef LDBL_IMPLICIT_NBIT
#define MANH_SIZE (LDBL_MANH_SIZE + 1)
#define INC_MANH(u, c) do { \
uint64_t o = u.bits.manh; \
u.bits.manh += (c); \
if (u.bits.manh < o) \
u.bits.exp++; \
} while (0)
#else
#define MANH_SIZE LDBL_MANH_SIZE
#define INC_MANH(u, c) do { \
uint64_t o = u.bits.manh; \
u.bits.manh += (c); \
if (u.bits.manh < o) { \
u.bits.exp++; \
u.bits.manh |= 1llu << (LDBL_MANH_SIZE - 1); \
} \
} while (0)
#endif
long double
ceill(long double x)
{
union IEEEl2bits u = { .e = x };
int e = u.bits.exp - LDBL_MAX_EXP + 1;
if (e < MANH_SIZE - 1) {
if (e < 0) { /* raise inexact if x != 0 */
if (u.bits.exp > 0 || (u.bits.manh | u.bits.manl) != 0)
u.e = u.bits.sign ? 0.0 : 1.0;
} else {
uint64_t m = ((1llu << MANH_SIZE) - 1) >> (e + 1);
if (((u.bits.manh & m) | u.bits.manl) == 0)
return (x); /* x is integral */
/* raise inexact flag */
if (!u.bits.sign) {
#ifdef LDBL_IMPLICIT_NBIT
if (e == 0)
u.bits.exp++;
else
#endif
INC_MANH(u, 1llu << (MANH_SIZE - e - 1));
}
u.bits.manh &= ~m;
u.bits.manl = 0;
}
} else if (e < LDBL_MANT_DIG - 1) {
uint64_t m = (uint64_t)-1 >> (64 - LDBL_MANT_DIG + e + 1);
if ((u.bits.manl & m) == 0)
return (x); /* x is integral */
/* raise inexact flag */
if (!u.bits.sign) {
if (e == MANH_SIZE - 1)
INC_MANH(u, 1);
else {
uint64_t o = u.bits.manl;
u.bits.manl += 1llu << (LDBL_MANT_DIG - e - 1);
if (u.bits.manl < o) /* got a carry */
INC_MANH(u, 1);
}
}
u.bits.manl &= ~m;
}
return (u.e);
}