diff options
Diffstat (limited to 'sysdeps/ieee754/dbl-64/s_ilogb.c')
| -rw-r--r-- | sysdeps/ieee754/dbl-64/s_ilogb.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_ilogb.c b/sysdeps/ieee754/dbl-64/s_ilogb.c index 820f01c9b2..89a833781d 100644 --- a/sysdeps/ieee754/dbl-64/s_ilogb.c +++ b/sysdeps/ieee754/dbl-64/s_ilogb.c @@ -16,10 +16,12 @@ static char rcsid[] = "$NetBSD: s_ilogb.c,v 1.9 1995/05/10 20:47:28 jtc Exp $"; /* ilogb(double x) * return the binary exponent of non-zero x - * ilogb(0) = 0x80000001 - * ilogb(inf/NaN) = 0x7fffffff (no signal is raised) + * ilogb(0) = FP_ILOGB0 + * ilogb(NaN) = FP_ILOGBNAN (no signal is raised) + * ilogb(+-Inf) = INT_MAX (no signal is raised) */ +#include <limits.h> #include "math.h" #include "math_private.h" @@ -47,7 +49,13 @@ static char rcsid[] = "$NetBSD: s_ilogb.c,v 1.9 1995/05/10 20:47:28 jtc Exp $"; return ix; } else if (hx<0x7ff00000) return (hx>>20)-1023; - else return FP_ILOGBNAN; + else if (FP_ILOGBNAN != INT_MAX) { + /* ISO C99 requires ilogb(+-Inf) == INT_MAX. */ + GET_LOW_WORD(lx,x); + if(((hx^0x7ff00000)|lx) == 0) + return INT_MAX; + } + return FP_ILOGBNAN; } weak_alias (__ilogb, ilogb) #ifdef NO_LONG_DOUBLE |