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authorUlrich Drepper <drepper@redhat.com>1999-07-14 00:54:57 +0000
committerUlrich Drepper <drepper@redhat.com>1999-07-14 00:54:57 +0000
commitabfbdde177c3a7155070dda1b2cdc8292054cc26 (patch)
treee021306b596381fbf8311d2b7eb294e918ff17c8 /sysdeps/libm-ieee754/s_log2f.c
parent86421aa57ecfd70963ae66848bd6a6dd3b8e0fe6 (diff)
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Update.
Diffstat (limited to 'sysdeps/libm-ieee754/s_log2f.c')
-rw-r--r--sysdeps/libm-ieee754/s_log2f.c91
1 files changed, 0 insertions, 91 deletions
diff --git a/sysdeps/libm-ieee754/s_log2f.c b/sysdeps/libm-ieee754/s_log2f.c
deleted file mode 100644
index 2377acd36a..0000000000
--- a/sysdeps/libm-ieee754/s_log2f.c
+++ /dev/null
@@ -1,91 +0,0 @@
-/* e_logf.c -- float version of e_log.c.
- * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
- * adapted for log2 by Ulrich Drepper <drepper@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"
-
-#ifdef __STDC__
-static const float
-#else
-static float
-#endif
-ln2 = 0.69314718055994530942,
-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 __log2f(float x)
-#else
-	float __log2f(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/(x-x);		/* log(+-0)=-inf */
-	    if (ix<0) return (x-x)/(x-x);	/* 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);
-	dk = (float)k;
-	f = x-(float)1.0;
-	if((0x007fffff&(15+ix))<16) {	/* |f| < 2**-20 */
-	    if(f==zero) return dk;
-	    R = f*f*((float)0.5-(float)0.33333333333333333*f);
-	    return dk-(R-f)/ln2;
-	}
- 	s = f/((float)2.0+f);
-	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;
-	    return dk-((hfsq-(s*(hfsq+R)))-f)/ln2;
-	} else {
-	    return dk-((s*(f-R))-f)/ln2;
-	}
-}
-weak_alias (__log2f, log2f)