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-rw-r--r--src/math/e_expf.c91
1 files changed, 0 insertions, 91 deletions
diff --git a/src/math/e_expf.c b/src/math/e_expf.c
deleted file mode 100644
index 99818edc..00000000
--- a/src/math/e_expf.c
+++ /dev/null
@@ -1,91 +0,0 @@
-/* e_expf.c -- float version of e_exp.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
-one = 1.0,
-halF[2] = {0.5,-0.5,},
-huge = 1.0e+30,
-twom100 = 7.8886090522e-31, /* 2**-100=0x0d800000 */
-o_threshold= 8.8721679688e+01, /* 0x42b17180 */
-u_threshold= -1.0397208405e+02, /* 0xc2cff1b5 */
-ln2HI[2] ={ 6.9313812256e-01, /* 0x3f317180 */
- -6.9313812256e-01,}, /* 0xbf317180 */
-ln2LO[2] ={ 9.0580006145e-06, /* 0x3717f7d1 */
- -9.0580006145e-06,}, /* 0xb717f7d1 */
-invln2 = 1.4426950216e+00, /* 0x3fb8aa3b */
-P1 = 1.6666667163e-01, /* 0x3e2aaaab */
-P2 = -2.7777778450e-03, /* 0xbb360b61 */
-P3 = 6.6137559770e-05, /* 0x388ab355 */
-P4 = -1.6533901999e-06, /* 0xb5ddea0e */
-P5 = 4.1381369442e-08; /* 0x3331bb4c */
-
-float
-expf(float x) /* default IEEE double exp */
-{
- float y,hi=0.0,lo=0.0,c,t;
- int32_t k=0,xsb;
- uint32_t hx;
-
- GET_FLOAT_WORD(hx,x);
- xsb = (hx>>31)&1; /* sign bit of x */
- hx &= 0x7fffffff; /* high word of |x| */
-
- /* filter out non-finite argument */
- if(hx >= 0x42b17218) { /* if |x|>=88.721... */
- if(hx>0x7f800000)
- return x+x; /* NaN */
- if(hx==0x7f800000)
- return (xsb==0)? x:0.0; /* exp(+-inf)={inf,0} */
- if(x > o_threshold) return huge*huge; /* overflow */
- if(x < u_threshold) return twom100*twom100; /* underflow */
- }
-
- /* argument reduction */
- if(hx > 0x3eb17218) { /* if |x| > 0.5 ln2 */
- if(hx < 0x3F851592) { /* and |x| < 1.5 ln2 */
- hi = x-ln2HI[xsb]; lo=ln2LO[xsb]; k = 1-xsb-xsb;
- } else {
- k = invln2*x+halF[xsb];
- t = k;
- hi = x - t*ln2HI[0]; /* t*ln2HI is exact here */
- lo = t*ln2LO[0];
- }
- x = hi - lo;
- }
- else if(hx < 0x31800000) { /* when |x|<2**-28 */
- if(huge+x>one) return one+x;/* trigger inexact */
- }
- else k = 0;
-
- /* x is now in primary range */
- t = x*x;
- c = x - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))));
- if(k==0) return one-((x*c)/(c-(float)2.0)-x);
- else y = one-((lo-(x*c)/((float)2.0-c))-hi);
- if(k >= -125) {
- uint32_t hy;
- GET_FLOAT_WORD(hy,y);
- SET_FLOAT_WORD(y,hy+(k<<23)); /* add k to y's exponent */
- return y;
- } else {
- uint32_t hy;
- GET_FLOAT_WORD(hy,y);
- SET_FLOAT_WORD(y,hy+((k+100)<<23)); /* add k to y's exponent */
- return y*twom100;
- }
-}