diff options
Diffstat (limited to 'newlib/libm/math/ef_log.c')
-rw-r--r-- | newlib/libm/math/ef_log.c | 92 |
1 files changed, 0 insertions, 92 deletions
diff --git a/newlib/libm/math/ef_log.c b/newlib/libm/math/ef_log.c deleted file mode 100644 index 87d6af2..0000000 --- a/newlib/libm/math/ef_log.c +++ /dev/null @@ -1,92 +0,0 @@ -/* ef_log.c -- float version of e_log.c. - * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. - */ - -/* - * ==================================================== - * 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. - * ==================================================== - */ - -#include "fdlibm.h" - -#ifdef __STDC__ -static const float -#else -static float -#endif -ln2_hi = 6.9313812256e-01, /* 0x3f317180 */ -ln2_lo = 9.0580006145e-06, /* 0x3717f7d1 */ -two25 = 3.355443200e+07, /* 0x4c000000 */ -Lg1 = 6.6666668653e-01, /* 3F2AAAAB */ -Lg2 = 4.0000000596e-01, /* 3ECCCCCD */ -Lg3 = 2.8571429849e-01, /* 3E924925 */ -Lg4 = 2.2222198546e-01, /* 3E638E29 */ -Lg5 = 1.8183572590e-01, /* 3E3A3325 */ -Lg6 = 1.5313838422e-01, /* 3E1CD04F */ -Lg7 = 1.4798198640e-01; /* 3E178897 */ - -#ifdef __STDC__ -static const float zero = 0.0; -#else -static float zero = 0.0; -#endif - -#ifdef __STDC__ - float __ieee754_logf(float x) -#else - float __ieee754_logf(x) - float x; -#endif -{ - float hfsq,f,s,z,R,w,t1,t2,dk; - __int32_t k,ix,i,j; - - GET_FLOAT_WORD(ix,x); - - k=0; - if (ix < 0x00800000) { /* x < 2**-126 */ - if ((ix&0x7fffffff)==0) - return -two25/zero; /* log(+-0)=-inf */ - if (ix<0) return (x-x)/zero; /* log(-#) = NaN */ - k -= 25; x *= two25; /* subnormal number, scale up x */ - GET_FLOAT_WORD(ix,x); - } - if (ix >= 0x7f800000) return x+x; - k += (ix>>23)-127; - ix &= 0x007fffff; - 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; - if((0x007fffff&(15+ix))<16) { /* |f| < 2**-20 */ - if(f==zero) { if(k==0) return zero; else {dk=(float)k; - return dk*ln2_hi+dk*ln2_lo;}} - R = f*f*((float)0.5-(float)0.33333333333333333*f); - if(k==0) return f-R; else {dk=(float)k; - return dk*ln2_hi-((R-dk*ln2_lo)-f);} - } - s = f/((float)2.0+f); - dk = (float)k; - z = s*s; - i = ix-(0x6147a<<3); - w = z*z; - j = (0x6b851<<3)-ix; - t1= w*(Lg2+w*(Lg4+w*Lg6)); - t2= z*(Lg1+w*(Lg3+w*(Lg5+w*Lg7))); - i |= j; - R = t2+t1; - if(i>0) { - hfsq=(float)0.5*f*f; - if(k==0) return f-(hfsq-s*(hfsq+R)); else - return dk*ln2_hi-((hfsq-(s*(hfsq+R)+dk*ln2_lo))-f); - } else { - if(k==0) return f-s*(f-R); else - return dk*ln2_hi-((s*(f-R)-dk*ln2_lo)-f); - } -} |