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-rw-r--r--src/math/e_powf.c243
1 files changed, 0 insertions, 243 deletions
diff --git a/src/math/e_powf.c b/src/math/e_powf.c
deleted file mode 100644
index ae61c246..00000000
--- a/src/math/e_powf.c
+++ /dev/null
@@ -1,243 +0,0 @@
-/* e_powf.c -- float version of e_pow.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
-bp[] = {1.0, 1.5,},
-dp_h[] = { 0.0, 5.84960938e-01,}, /* 0x3f15c000 */
-dp_l[] = { 0.0, 1.56322085e-06,}, /* 0x35d1cfdc */
-zero = 0.0,
-one = 1.0,
-two = 2.0,
-two24 = 16777216.0, /* 0x4b800000 */
-huge = 1.0e30,
-tiny = 1.0e-30,
- /* poly coefs for (3/2)*(log(x)-2s-2/3*s**3 */
-L1 = 6.0000002384e-01, /* 0x3f19999a */
-L2 = 4.2857143283e-01, /* 0x3edb6db7 */
-L3 = 3.3333334327e-01, /* 0x3eaaaaab */
-L4 = 2.7272811532e-01, /* 0x3e8ba305 */
-L5 = 2.3066075146e-01, /* 0x3e6c3255 */
-L6 = 2.0697501302e-01, /* 0x3e53f142 */
-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 */
-lg2 = 6.9314718246e-01, /* 0x3f317218 */
-lg2_h = 6.93145752e-01, /* 0x3f317200 */
-lg2_l = 1.42860654e-06, /* 0x35bfbe8c */
-ovt = 4.2995665694e-08, /* -(128-log2(ovfl+.5ulp)) */
-cp = 9.6179670095e-01, /* 0x3f76384f =2/(3ln2) */
-cp_h = 9.6179199219e-01, /* 0x3f763800 =head of cp */
-cp_l = 4.7017383622e-06, /* 0x369dc3a0 =tail of cp_h */
-ivln2 = 1.4426950216e+00, /* 0x3fb8aa3b =1/ln2 */
-ivln2_h = 1.4426879883e+00, /* 0x3fb8aa00 =16b 1/ln2*/
-ivln2_l = 7.0526075433e-06; /* 0x36eca570 =1/ln2 tail*/
-
-float
-powf(float x, float y)
-{
- float z,ax,z_h,z_l,p_h,p_l;
- float y1,t1,t2,r,s,sn,t,u,v,w;
- int32_t i,j,k,yisint,n;
- int32_t hx,hy,ix,iy,is;
-
- GET_FLOAT_WORD(hx,x);
- GET_FLOAT_WORD(hy,y);
- ix = hx&0x7fffffff; iy = hy&0x7fffffff;
-
- /* y==zero: x**0 = 1 */
- if(iy==0) return one;
-
- /* +-NaN return x+y */
- if(ix > 0x7f800000 ||
- iy > 0x7f800000)
- return x+y;
-
- /* determine if y is an odd int when x < 0
- * yisint = 0 ... y is not an integer
- * yisint = 1 ... y is an odd int
- * yisint = 2 ... y is an even int
- */
- yisint = 0;
- if(hx<0) {
- if(iy>=0x4b800000) yisint = 2; /* even integer y */
- else if(iy>=0x3f800000) {
- k = (iy>>23)-0x7f; /* exponent */
- j = iy>>(23-k);
- if((j<<(23-k))==iy) yisint = 2-(j&1);
- }
- }
-
- /* special value of y */
- if (iy==0x7f800000) { /* y is +-inf */
- if (ix==0x3f800000)
- return y - y; /* inf**+-1 is NaN */
- else if (ix > 0x3f800000)/* (|x|>1)**+-inf = inf,0 */
- return (hy>=0)? y: zero;
- else /* (|x|<1)**-,+inf = inf,0 */
- return (hy<0)?-y: zero;
- }
- if(iy==0x3f800000) { /* y is +-1 */
- if(hy<0) return one/x; else return x;
- }
- if(hy==0x40000000) return x*x; /* y is 2 */
- if(hy==0x3f000000) { /* y is 0.5 */
- if(hx>=0) /* x >= +0 */
- return sqrtf(x);
- }
-
- ax = fabsf(x);
- /* special value of x */
- if(ix==0x7f800000||ix==0||ix==0x3f800000){
- z = ax; /*x is +-0,+-inf,+-1*/
- if(hy<0) z = one/z; /* z = (1/|x|) */
- if(hx<0) {
- if(((ix-0x3f800000)|yisint)==0) {
- z = (z-z)/(z-z); /* (-1)**non-int is NaN */
- } else if(yisint==1)
- z = -z; /* (x<0)**odd = -(|x|**odd) */
- }
- return z;
- }
-
- n = ((uint32_t)hx>>31)-1;
-
- /* (x<0)**(non-int) is NaN */
- if((n|yisint)==0) return (x-x)/(x-x);
-
- sn = one; /* s (sign of result -ve**odd) = -1 else = 1 */
- if((n|(yisint-1))==0) sn = -one;/* (-ve)**(odd int) */
-
- /* |y| is huge */
- if(iy>0x4d000000) { /* if |y| > 2**27 */
- /* over/underflow if x is not close to one */
- if(ix<0x3f7ffff8) return (hy<0)? sn*huge*huge:sn*tiny*tiny;
- if(ix>0x3f800007) return (hy>0)? sn*huge*huge:sn*tiny*tiny;
- /* now |1-x| is tiny <= 2**-20, suffice to compute
- log(x) by x-x^2/2+x^3/3-x^4/4 */
- t = ax-1; /* t has 20 trailing zeros */
- w = (t*t)*((float)0.5-t*((float)0.333333333333-t*(float)0.25));
- u = ivln2_h*t; /* ivln2_h has 16 sig. bits */
- v = t*ivln2_l-w*ivln2;
- t1 = u+v;
- GET_FLOAT_WORD(is,t1);
- SET_FLOAT_WORD(t1,is&0xfffff000);
- t2 = v-(t1-u);
- } else {
- float s2,s_h,s_l,t_h,t_l;
- n = 0;
- /* take care subnormal number */
- if(ix<0x00800000)
- {ax *= two24; n -= 24; GET_FLOAT_WORD(ix,ax); }
- n += ((ix)>>23)-0x7f;
- j = ix&0x007fffff;
- /* determine interval */
- ix = j|0x3f800000; /* normalize ix */
- if(j<=0x1cc471) k=0; /* |x|<sqrt(3/2) */
- else if(j<0x5db3d7) k=1; /* |x|<sqrt(3) */
- else {k=0;n+=1;ix -= 0x00800000;}
- SET_FLOAT_WORD(ax,ix);
-
- /* compute s = s_h+s_l = (x-1)/(x+1) or (x-1.5)/(x+1.5) */
- u = ax-bp[k]; /* bp[0]=1.0, bp[1]=1.5 */
- v = one/(ax+bp[k]);
- s = u*v;
- s_h = s;
- GET_FLOAT_WORD(is,s_h);
- SET_FLOAT_WORD(s_h,is&0xfffff000);
- /* t_h=ax+bp[k] High */
- is = ((ix>>1)&0xfffff000)|0x20000000;
- SET_FLOAT_WORD(t_h,is+0x00400000+(k<<21));
- t_l = ax - (t_h-bp[k]);
- s_l = v*((u-s_h*t_h)-s_h*t_l);
- /* compute log(ax) */
- s2 = s*s;
- r = s2*s2*(L1+s2*(L2+s2*(L3+s2*(L4+s2*(L5+s2*L6)))));
- r += s_l*(s_h+s);
- s2 = s_h*s_h;
- t_h = (float)3.0+s2+r;
- GET_FLOAT_WORD(is,t_h);
- SET_FLOAT_WORD(t_h,is&0xfffff000);
- t_l = r-((t_h-(float)3.0)-s2);
- /* u+v = s*(1+...) */
- u = s_h*t_h;
- v = s_l*t_h+t_l*s;
- /* 2/(3log2)*(s+...) */
- p_h = u+v;
- GET_FLOAT_WORD(is,p_h);
- SET_FLOAT_WORD(p_h,is&0xfffff000);
- p_l = v-(p_h-u);
- z_h = cp_h*p_h; /* cp_h+cp_l = 2/(3*log2) */
- z_l = cp_l*p_h+p_l*cp+dp_l[k];
- /* log2(ax) = (s+..)*2/(3*log2) = n + dp_h + z_h + z_l */
- t = (float)n;
- t1 = (((z_h+z_l)+dp_h[k])+t);
- GET_FLOAT_WORD(is,t1);
- SET_FLOAT_WORD(t1,is&0xfffff000);
- t2 = z_l-(((t1-t)-dp_h[k])-z_h);
- }
-
- /* split up y into y1+y2 and compute (y1+y2)*(t1+t2) */
- GET_FLOAT_WORD(is,y);
- SET_FLOAT_WORD(y1,is&0xfffff000);
- p_l = (y-y1)*t1+y*t2;
- p_h = y1*t1;
- z = p_l+p_h;
- GET_FLOAT_WORD(j,z);
- if (j>0x43000000) /* if z > 128 */
- return sn*huge*huge; /* overflow */
- else if (j==0x43000000) { /* if z == 128 */
- if(p_l+ovt>z-p_h) return sn*huge*huge; /* overflow */
- }
- else if ((j&0x7fffffff)>0x43160000) /* z <= -150 */
- return sn*tiny*tiny; /* underflow */
- else if (j==0xc3160000){ /* z == -150 */
- if(p_l<=z-p_h) return sn*tiny*tiny; /* underflow */
- }
- /*
- * compute 2**(p_h+p_l)
- */
- i = j&0x7fffffff;
- k = (i>>23)-0x7f;
- n = 0;
- if(i>0x3f000000) { /* if |z| > 0.5, set n = [z+0.5] */
- n = j+(0x00800000>>(k+1));
- k = ((n&0x7fffffff)>>23)-0x7f; /* new k for n */
- SET_FLOAT_WORD(t,n&~(0x007fffff>>k));
- n = ((n&0x007fffff)|0x00800000)>>(23-k);
- if(j<0) n = -n;
- p_h -= t;
- }
- t = p_l+p_h;
- GET_FLOAT_WORD(is,t);
- SET_FLOAT_WORD(t,is&0xffff8000);
- u = t*lg2_h;
- v = (p_l-(t-p_h))*lg2+t*lg2_l;
- z = u+v;
- w = v-(z-u);
- t = z*z;
- t1 = z - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))));
- r = (z*t1)/(t1-two)-(w+z*w);
- z = one-(r-z);
- GET_FLOAT_WORD(j,z);
- j += (n<<23);
- if((j>>23)<=0) z = scalbnf(z,n); /* subnormal output */
- else SET_FLOAT_WORD(z,j);
- return sn*z;
-}
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