Lg3 = 0x91e9ee.0p-25, /* 0.28498786688 */
Lg4 = 0xf89e26.0p-26; /* 0.24279078841 */
-static const float zero = 0.0;
-
float logf(float x)
{
float hfsq,f,s,z,R,w,t1,t2,dk;
k = 0;
if (ix < 0x00800000) { /* x < 2**-126 */
if ((ix & 0x7fffffff) == 0)
- return -two25/zero; /* log(+-0)=-inf */
+ return -two25/0.0f; /* log(+-0)=-inf */
if (ix < 0)
- return (x-x)/zero; /* log(-#) = NaN */
+ return (x-x)/0.0f; /* log(-#) = NaN */
/* subnormal number, scale up x */
k -= 25;
x *= two25;
i = (ix + (0x95f64<<3)) & 0x800000;
SET_FLOAT_WORD(x, ix|(i^0x3f800000)); /* normalize x or x/2 */
k += i>>23;
- f = x - (float)1.0;
+ f = x - 1.0f;
if ((0x007fffff & (0x8000 + ix)) < 0xc000) { /* -2**-9 <= f < 2**-9 */
- if (f == zero) {
+ if (f == 0.0f) {
if (k == 0)
- return zero;
+ return 0.0f;
dk = (float)k;
return dk*ln2_hi + dk*ln2_lo;
}
- R = f*f*((float)0.5 - (float)0.33333333333333333*f);
+ R = f*f*(0.5f - 0.33333333333333333f*f);
if (k == 0)
return f-R;
dk = (float)k;
return dk*ln2_hi - ((R-dk*ln2_lo)-f);
}
- s = f/((float)2.0+f);
+ s = f/(2.0f + f);
dk = (float)k;
z = s*s;
i = ix-(0x6147a<<3);
i |= j;
R = t2 + t1;
if (i > 0) {
- hfsq = (float)0.5*f*f;
+ hfsq = 0.5f * f * f;
if (k == 0)
return f - (hfsq-s*(hfsq+R));
return dk*ln2_hi - ((hfsq-(s*(hfsq+R)+dk*ln2_lo))-f);