diff options
Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/s_logbl.c')
| -rw-r--r-- | sysdeps/ieee754/ldbl-128ibm/s_logbl.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_logbl.c b/sysdeps/ieee754/ldbl-128ibm/s_logbl.c new file mode 100644 index 0000000..0c61cda --- /dev/null +++ b/sysdeps/ieee754/ldbl-128ibm/s_logbl.c @@ -0,0 +1,47 @@ +/* s_logbl.c -- long double version of s_logb.c. + * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz. + */ + +/* + * ==================================================== + * 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. + * ==================================================== + */ + +#if defined(LIBM_SCCS) && !defined(lint) +static char rcsid[] = "$NetBSD: $"; +#endif + +/* + * long double logbl(x) + * IEEE 754 logb. Included to pass IEEE test suite. Not recommend. + * Use ilogb instead. + */ + +#include "math.h" +#include "math_private.h" +#include <math_ldbl_opt.h> + +#ifdef __STDC__ + long double __logbl(long double x) +#else + long double __logbl(x) + long double x; +#endif +{ + int64_t lx,hx; + GET_LDOUBLE_WORDS64(hx,lx,x); + hx &= 0x7fffffffffffffffLL; /* high |x| */ + if((hx|(lx&0x7fffffffffffffffLL))==0) return -1.0/fabs(x); + if(hx>=0x7ff0000000000000LL) return x*x; + if((hx>>=52)==0) /* IEEE 754 logb */ + return -1022.0; + else + return (long double) (hx-0x3ff); +} +long_double_symbol (libm, __logbl, logbl); |