diff options
author | obrien <obrien@FreeBSD.org> | 2002-06-29 03:23:18 +0000 |
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committer | obrien <obrien@FreeBSD.org> | 2002-06-29 03:23:18 +0000 |
commit | 30c36077fc101ded421a1e08f20779efc8a8375e (patch) | |
tree | 87544614462474f204670b7bffdfd58d23fe5e38 /lib | |
parent | c5dacda2d63e71093b0cb7b216dc749446baec05 (diff) | |
download | FreeBSD-src-30c36077fc101ded421a1e08f20779efc8a8375e.zip FreeBSD-src-30c36077fc101ded421a1e08f20779efc8a8375e.tar.gz |
Add frexp(3).
Obtained from: OpenBSD
Diffstat (limited to 'lib')
-rw-r--r-- | lib/libc/sparc64/gen/Makefile.inc | 4 | ||||
-rw-r--r-- | lib/libc/sparc64/gen/frexp.c | 78 |
2 files changed, 80 insertions, 2 deletions
diff --git a/lib/libc/sparc64/gen/Makefile.inc b/lib/libc/sparc64/gen/Makefile.inc index afc3a9e..8bedc5f 100644 --- a/lib/libc/sparc64/gen/Makefile.inc +++ b/lib/libc/sparc64/gen/Makefile.inc @@ -1,4 +1,4 @@ # $FreeBSD$ -SRCS+= _setjmp.S fixunsdfsi.S flt_rounds.c fpsetmask.c infinity.c isinf.c \ - ldexp.c modf.S setjmp.S sigsetjmp.S +SRCS+= _setjmp.S fixunsdfsi.S flt_rounds.c fpsetmask.c frexp.c \ + infinity.c isinf.c ldexp.c modf.S setjmp.S sigsetjmp.S diff --git a/lib/libc/sparc64/gen/frexp.c b/lib/libc/sparc64/gen/frexp.c new file mode 100644 index 0000000..e31a1c8 --- /dev/null +++ b/lib/libc/sparc64/gen/frexp.c @@ -0,0 +1,78 @@ +/* + * Copyright (c) 1992, 1993 + * The Regents of the University of California. All rights reserved. + * + * This software was developed by the Computer Systems Engineering group + * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and + * contributed to Berkeley. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#if defined(LIBC_SCCS) && !defined(lint) +static char rcsid[] = "$OpenBSD: frexp.c,v 1.2 2001/09/10 22:37:06 millert Exp $"; +#endif /* LIBC_SCCS and not lint */ +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/types.h> +#include <machine/ieee.h> + +/* + * Split the given value into a fraction in the range [0.5, 1.0) and + * an exponent, such that frac * (2^exp) == value. If value is 0, + * return 0. + */ +double +frexp(value, eptr) + double value; + int *eptr; +{ + union { + double v; + struct ieee_double s; + } u; + + if (value) { + /* + * Fractions in [0.5..1.0) have an exponent of 2^-1. + * Leave Inf and NaN alone, however. + * WHAT ABOUT DENORMS? + */ + u.v = value; + if (u.s.dbl_exp != DBL_EXP_INFNAN) { + *eptr = u.s.dbl_exp - (DBL_EXP_BIAS - 1); + u.s.dbl_exp = DBL_EXP_BIAS - 1; + } + return (u.v); + } else { + *eptr = 0; + return ((double)0); + } +} |