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-rw-r--r--src/math/e_logf.c81
1 files changed, 0 insertions, 81 deletions
diff --git a/src/math/e_logf.c b/src/math/e_logf.c
deleted file mode 100644
index 46a8b8ce..00000000
--- a/src/math/e_logf.c
+++ /dev/null
@@ -1,81 +0,0 @@
-/* e_logf.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 <math.h>
-#include "math_private.h"
-
-static const float
-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 */
-
-static const float zero = 0.0;
-
-float
-logf(float x)
-{
- 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);
- }
-}