diff options
Diffstat (limited to 'lib/libc/arch/mips/gen/frexp.c')
| -rw-r--r-- | lib/libc/arch/mips/gen/frexp.c | 49 |
1 files changed, 27 insertions, 22 deletions
diff --git a/lib/libc/arch/mips/gen/frexp.c b/lib/libc/arch/mips/gen/frexp.c index 181e1dc735d..21b0cb426a5 100644 --- a/lib/libc/arch/mips/gen/frexp.c +++ b/lib/libc/arch/mips/gen/frexp.c @@ -1,7 +1,13 @@ -/*- - * Copyright (c) 1991, 1993 +/* $OpenBSD: frexp.c,v 1.4 2001/09/10 22:37:06 millert Exp $ */ + +/* + * 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: @@ -32,13 +38,17 @@ */ #if defined(LIBC_SCCS) && !defined(lint) -static char rcsid[] = "$OpenBSD: frexp.c,v 1.3 1997/07/23 20:55:24 kstailey Exp $"; +static char rcsid[] = "$OpenBSD: frexp.c,v 1.4 2001/09/10 22:37:06 millert Exp $"; #endif /* LIBC_SCCS and not lint */ #include <sys/types.h> -#include <machine/endian.h> -#include <math.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; @@ -46,28 +56,23 @@ frexp(value, eptr) { union { double v; - struct { -#if BYTE_ORDER == LITTLE_ENDIAN - u_int u_mant2 : 32; - u_int u_mant1 : 20; - u_int u_exp : 11; - u_int u_sign : 1; -#else - u_int u_sign : 1; - u_int u_exp : 11; - u_int u_mant1 : 20; - u_int u_mant2 : 32; -#endif - } s; + 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; - *eptr = u.s.u_exp - 1022; - u.s.u_exp = 1022; - return(u.v); + 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); + return ((double)0); } } |