diff options
Diffstat (limited to 'lib/msun/src/e_log2.c')
| -rw-r--r-- | lib/msun/src/e_log2.c | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/lib/msun/src/e_log2.c b/lib/msun/src/e_log2.c index 6cf3dbc..d237759 100644 --- a/lib/msun/src/e_log2.c +++ b/lib/msun/src/e_log2.c @@ -15,7 +15,8 @@ __FBSDID("$FreeBSD$"); /* - * Return the base 2 logarithm of x. See k_log.c for details on the algorithm. + * Return the base 2 logarithm of x. See e_log.c and k_log.h for most + * comments. */ #include "math.h" @@ -38,14 +39,14 @@ __ieee754_log2(double x) EXTRACT_WORDS(hx,lx,x); - k=0; - if (hx < 0x00100000) { /* x < 2**-1022 */ - if (((hx&0x7fffffff)|lx)==0) - return -two54/zero; /* log(+-0)=-inf */ - if (hx<0) return (x-x)/zero; /* log(-#) = NaN */ - k -= 54; x *= two54; /* subnormal number, scale up x */ + k=0; + if (hx < 0x00100000) { /* x < 2**-1022 */ + if (((hx&0x7fffffff)|lx)==0) + return -two54/zero; /* log(+-0)=-inf */ + if (hx<0) return (x-x)/zero; /* log(-#) = NaN */ + k -= 54; x *= two54; /* subnormal number, scale up x */ GET_HIGH_WORD(hx,x); - } + } if (hx >= 0x7ff00000) return x+x; k += (hx>>20)-1023; hx &= 0x000fffff; |
