diff options
Diffstat (limited to 'sysdeps/ieee754/ldbl-96')
| -rw-r--r-- | sysdeps/ieee754/ldbl-96/s_logbl.c | 35 |
1 files changed, 21 insertions, 14 deletions
diff --git a/sysdeps/ieee754/ldbl-96/s_logbl.c b/sysdeps/ieee754/ldbl-96/s_logbl.c index 95b644c030..d8ad4bcfcf 100644 --- a/sysdeps/ieee754/ldbl-96/s_logbl.c +++ b/sysdeps/ieee754/ldbl-96/s_logbl.c @@ -14,10 +14,6 @@ * ==================================================== */ -#if defined(LIBM_SCCS) && !defined(lint) -static char rcsid[] = "$NetBSD: $"; -#endif - /* * long double logbl(x) * IEEE 754 logb. Included to pass IEEE test suite. Not recommend. @@ -27,16 +23,27 @@ static char rcsid[] = "$NetBSD: $"; #include <math.h> #include <math_private.h> -long double __logbl(long double x) +long double +__logbl (long double x) { - int32_t es,lx,ix; - GET_LDOUBLE_WORDS(es,ix,lx,x); - es &= 0x7fff; /* exponent */ - if((es|ix|lx)==0) return -1.0/fabs(x); - if(es==0x7fff) return x*x; - if(es==0) /* IEEE 754 logb */ - return -16382.0; - else - return (long double) (es-0x3fff); + int32_t es, lx, ix; + + GET_LDOUBLE_WORDS (es, ix, lx, x); + es &= 0x7fff; /* exponent */ + if ((es | ix | lx) == 0) + return -1.0 / fabs (x); + if (es == 0x7fff) + return x * x; + if (es == 0) /* IEEE 754 logb */ + { + /* POSIX specifies that denormal number is treated as + though it were normalized. */ + int m1 = (ix == 0) ? 0 : __builtin_clz (ix); + int m2 = (lx == 0) ? 0 : __builtin_clz (lx); + int ma = (m1 == 0) ? m2 + 32 : m1; + return -16382.0 - (long double)(ma); + } + return (long double) (es - 16383); } + weak_alias (__logbl, logbl) |