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-rw-r--r--lib/mlibc/options/ansi/musl-generic-math/pow.c328
1 files changed, 0 insertions, 328 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/pow.c b/lib/mlibc/options/ansi/musl-generic-math/pow.c
deleted file mode 100644
index 3ddc1b6..0000000
--- a/lib/mlibc/options/ansi/musl-generic-math/pow.c
+++ /dev/null
@@ -1,328 +0,0 @@
-/* origin: FreeBSD /usr/src/lib/msun/src/e_pow.c */
-/*
- * ====================================================
- * Copyright (C) 2004 by Sun Microsystems, Inc. All rights reserved.
- *
- * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice
- * is preserved.
- * ====================================================
- */
-/* pow(x,y) return x**y
- *
- * n
- * Method: Let x = 2 * (1+f)
- * 1. Compute and return log2(x) in two pieces:
- * log2(x) = w1 + w2,
- * where w1 has 53-24 = 29 bit trailing zeros.
- * 2. Perform y*log2(x) = n+y' by simulating muti-precision
- * arithmetic, where |y'|<=0.5.
- * 3. Return x**y = 2**n*exp(y'*log2)
- *
- * Special cases:
- * 1. (anything) ** 0 is 1
- * 2. 1 ** (anything) is 1
- * 3. (anything except 1) ** NAN is NAN
- * 4. NAN ** (anything except 0) is NAN
- * 5. +-(|x| > 1) ** +INF is +INF
- * 6. +-(|x| > 1) ** -INF is +0
- * 7. +-(|x| < 1) ** +INF is +0
- * 8. +-(|x| < 1) ** -INF is +INF
- * 9. -1 ** +-INF is 1
- * 10. +0 ** (+anything except 0, NAN) is +0
- * 11. -0 ** (+anything except 0, NAN, odd integer) is +0
- * 12. +0 ** (-anything except 0, NAN) is +INF, raise divbyzero
- * 13. -0 ** (-anything except 0, NAN, odd integer) is +INF, raise divbyzero
- * 14. -0 ** (+odd integer) is -0
- * 15. -0 ** (-odd integer) is -INF, raise divbyzero
- * 16. +INF ** (+anything except 0,NAN) is +INF
- * 17. +INF ** (-anything except 0,NAN) is +0
- * 18. -INF ** (+odd integer) is -INF
- * 19. -INF ** (anything) = -0 ** (-anything), (anything except odd integer)
- * 20. (anything) ** 1 is (anything)
- * 21. (anything) ** -1 is 1/(anything)
- * 22. (-anything) ** (integer) is (-1)**(integer)*(+anything**integer)
- * 23. (-anything except 0 and inf) ** (non-integer) is NAN
- *
- * Accuracy:
- * pow(x,y) returns x**y nearly rounded. In particular
- * pow(integer,integer)
- * always returns the correct integer provided it is
- * representable.
- *
- * Constants :
- * The hexadecimal values are the intended ones for the following
- * constants. The decimal values may be used, provided that the
- * compiler will convert from decimal to binary accurately enough
- * to produce the hexadecimal values shown.
- */
-
-#include "libm.h"
-
-static const double
-bp[] = {1.0, 1.5,},
-dp_h[] = { 0.0, 5.84962487220764160156e-01,}, /* 0x3FE2B803, 0x40000000 */
-dp_l[] = { 0.0, 1.35003920212974897128e-08,}, /* 0x3E4CFDEB, 0x43CFD006 */
-two53 = 9007199254740992.0, /* 0x43400000, 0x00000000 */
-huge = 1.0e300,
-tiny = 1.0e-300,
-/* poly coefs for (3/2)*(log(x)-2s-2/3*s**3 */
-L1 = 5.99999999999994648725e-01, /* 0x3FE33333, 0x33333303 */
-L2 = 4.28571428578550184252e-01, /* 0x3FDB6DB6, 0xDB6FABFF */
-L3 = 3.33333329818377432918e-01, /* 0x3FD55555, 0x518F264D */
-L4 = 2.72728123808534006489e-01, /* 0x3FD17460, 0xA91D4101 */
-L5 = 2.30660745775561754067e-01, /* 0x3FCD864A, 0x93C9DB65 */
-L6 = 2.06975017800338417784e-01, /* 0x3FCA7E28, 0x4A454EEF */
-P1 = 1.66666666666666019037e-01, /* 0x3FC55555, 0x5555553E */
-P2 = -2.77777777770155933842e-03, /* 0xBF66C16C, 0x16BEBD93 */
-P3 = 6.61375632143793436117e-05, /* 0x3F11566A, 0xAF25DE2C */
-P4 = -1.65339022054652515390e-06, /* 0xBEBBBD41, 0xC5D26BF1 */
-P5 = 4.13813679705723846039e-08, /* 0x3E663769, 0x72BEA4D0 */
-lg2 = 6.93147180559945286227e-01, /* 0x3FE62E42, 0xFEFA39EF */
-lg2_h = 6.93147182464599609375e-01, /* 0x3FE62E43, 0x00000000 */
-lg2_l = -1.90465429995776804525e-09, /* 0xBE205C61, 0x0CA86C39 */
-ovt = 8.0085662595372944372e-017, /* -(1024-log2(ovfl+.5ulp)) */
-cp = 9.61796693925975554329e-01, /* 0x3FEEC709, 0xDC3A03FD =2/(3ln2) */
-cp_h = 9.61796700954437255859e-01, /* 0x3FEEC709, 0xE0000000 =(float)cp */
-cp_l = -7.02846165095275826516e-09, /* 0xBE3E2FE0, 0x145B01F5 =tail of cp_h*/
-ivln2 = 1.44269504088896338700e+00, /* 0x3FF71547, 0x652B82FE =1/ln2 */
-ivln2_h = 1.44269502162933349609e+00, /* 0x3FF71547, 0x60000000 =24b 1/ln2*/
-ivln2_l = 1.92596299112661746887e-08; /* 0x3E54AE0B, 0xF85DDF44 =1/ln2 tail*/
-
-double pow(double x, double y)
-{
- double z,ax,z_h,z_l,p_h,p_l;
- double y1,t1,t2,r,s,t,u,v,w;
- int32_t i,j,k,yisint,n;
- int32_t hx,hy,ix,iy;
- uint32_t lx,ly;
-
- EXTRACT_WORDS(hx, lx, x);
- EXTRACT_WORDS(hy, ly, y);
- ix = hx & 0x7fffffff;
- iy = hy & 0x7fffffff;
-
- /* x**0 = 1, even if x is NaN */
- if ((iy|ly) == 0)
- return 1.0;
- /* 1**y = 1, even if y is NaN */
- if (hx == 0x3ff00000 && lx == 0)
- return 1.0;
- /* NaN if either arg is NaN */
- if (ix > 0x7ff00000 || (ix == 0x7ff00000 && lx != 0) ||
- iy > 0x7ff00000 || (iy == 0x7ff00000 && ly != 0))
- 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 >= 0x43400000)
- yisint = 2; /* even integer y */
- else if (iy >= 0x3ff00000) {
- k = (iy>>20) - 0x3ff; /* exponent */
- if (k > 20) {
- uint32_t j = ly>>(52-k);
- if ((j<<(52-k)) == ly)
- yisint = 2 - (j&1);
- } else if (ly == 0) {
- uint32_t j = iy>>(20-k);
- if ((j<<(20-k)) == iy)
- yisint = 2 - (j&1);
- }
- }
- }
-
- /* special value of y */
- if (ly == 0) {
- if (iy == 0x7ff00000) { /* y is +-inf */
- if (((ix-0x3ff00000)|lx) == 0) /* (-1)**+-inf is 1 */
- return 1.0;
- else if (ix >= 0x3ff00000) /* (|x|>1)**+-inf = inf,0 */
- return hy >= 0 ? y : 0.0;
- else /* (|x|<1)**+-inf = 0,inf */
- return hy >= 0 ? 0.0 : -y;
- }
- if (iy == 0x3ff00000) { /* y is +-1 */
- if (hy >= 0)
- return x;
- y = 1/x;
-#if FLT_EVAL_METHOD!=0
- {
- union {double f; uint64_t i;} u = {y};
- uint64_t i = u.i & -1ULL/2;
- if (i>>52 == 0 && (i&(i-1)))
- FORCE_EVAL((float)y);
- }
-#endif
- return y;
- }
- if (hy == 0x40000000) /* y is 2 */
- return x*x;
- if (hy == 0x3fe00000) { /* y is 0.5 */
- if (hx >= 0) /* x >= +0 */
- return sqrt(x);
- }
- }
-
- ax = fabs(x);
- /* special value of x */
- if (lx == 0) {
- if (ix == 0x7ff00000 || ix == 0 || ix == 0x3ff00000) { /* x is +-0,+-inf,+-1 */
- z = ax;
- if (hy < 0) /* z = (1/|x|) */
- z = 1.0/z;
- if (hx < 0) {
- if (((ix-0x3ff00000)|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;
- }
- }
-
- s = 1.0; /* sign of result */
- if (hx < 0) {
- if (yisint == 0) /* (x<0)**(non-int) is NaN */
- return (x-x)/(x-x);
- if (yisint == 1) /* (x<0)**(odd int) */
- s = -1.0;
- }
-
- /* |y| is huge */
- if (iy > 0x41e00000) { /* if |y| > 2**31 */
- if (iy > 0x43f00000) { /* if |y| > 2**64, must o/uflow */
- if (ix <= 0x3fefffff)
- return hy < 0 ? huge*huge : tiny*tiny;
- if (ix >= 0x3ff00000)
- return hy > 0 ? huge*huge : tiny*tiny;
- }
- /* over/underflow if x is not close to one */
- if (ix < 0x3fefffff)
- return hy < 0 ? s*huge*huge : s*tiny*tiny;
- if (ix > 0x3ff00000)
- return hy > 0 ? s*huge*huge : s*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 - 1.0; /* t has 20 trailing zeros */
- w = (t*t)*(0.5 - t*(0.3333333333333333333333-t*0.25));
- u = ivln2_h*t; /* ivln2_h has 21 sig. bits */
- v = t*ivln2_l - w*ivln2;
- t1 = u + v;
- SET_LOW_WORD(t1, 0);
- t2 = v - (t1-u);
- } else {
- double ss,s2,s_h,s_l,t_h,t_l;
- n = 0;
- /* take care subnormal number */
- if (ix < 0x00100000) {
- ax *= two53;
- n -= 53;
- GET_HIGH_WORD(ix,ax);
- }
- n += ((ix)>>20) - 0x3ff;
- j = ix & 0x000fffff;
- /* determine interval */
- ix = j | 0x3ff00000; /* normalize ix */
- if (j <= 0x3988E) /* |x|<sqrt(3/2) */
- k = 0;
- else if (j < 0xBB67A) /* |x|<sqrt(3) */
- k = 1;
- else {
- k = 0;
- n += 1;
- ix -= 0x00100000;
- }
- SET_HIGH_WORD(ax, ix);
-
- /* compute ss = 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 = 1.0/(ax+bp[k]);
- ss = u*v;
- s_h = ss;
- SET_LOW_WORD(s_h, 0);
- /* t_h=ax+bp[k] High */
- t_h = 0.0;
- SET_HIGH_WORD(t_h, ((ix>>1)|0x20000000) + 0x00080000 + (k<<18));
- t_l = ax - (t_h-bp[k]);
- s_l = v*((u-s_h*t_h)-s_h*t_l);
- /* compute log(ax) */
- s2 = ss*ss;
- r = s2*s2*(L1+s2*(L2+s2*(L3+s2*(L4+s2*(L5+s2*L6)))));
- r += s_l*(s_h+ss);
- s2 = s_h*s_h;
- t_h = 3.0 + s2 + r;
- SET_LOW_WORD(t_h, 0);
- t_l = r - ((t_h-3.0)-s2);
- /* u+v = ss*(1+...) */
- u = s_h*t_h;
- v = s_l*t_h + t_l*ss;
- /* 2/(3log2)*(ss+...) */
- p_h = u + v;
- SET_LOW_WORD(p_h, 0);
- 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) = (ss+..)*2/(3*log2) = n + dp_h + z_h + z_l */
- t = (double)n;
- t1 = ((z_h + z_l) + dp_h[k]) + t;
- SET_LOW_WORD(t1, 0);
- t2 = z_l - (((t1 - t) - dp_h[k]) - z_h);
- }
-
- /* split up y into y1+y2 and compute (y1+y2)*(t1+t2) */
- y1 = y;
- SET_LOW_WORD(y1, 0);
- p_l = (y-y1)*t1 + y*t2;
- p_h = y1*t1;
- z = p_l + p_h;
- EXTRACT_WORDS(j, i, z);
- if (j >= 0x40900000) { /* z >= 1024 */
- if (((j-0x40900000)|i) != 0) /* if z > 1024 */
- return s*huge*huge; /* overflow */
- if (p_l + ovt > z - p_h)
- return s*huge*huge; /* overflow */
- } else if ((j&0x7fffffff) >= 0x4090cc00) { /* z <= -1075 */ // FIXME: instead of abs(j) use unsigned j
- if (((j-0xc090cc00)|i) != 0) /* z < -1075 */
- return s*tiny*tiny; /* underflow */
- if (p_l <= z - p_h)
- return s*tiny*tiny; /* underflow */
- }
- /*
- * compute 2**(p_h+p_l)
- */
- i = j & 0x7fffffff;
- k = (i>>20) - 0x3ff;
- n = 0;
- if (i > 0x3fe00000) { /* if |z| > 0.5, set n = [z+0.5] */
- n = j + (0x00100000>>(k+1));
- k = ((n&0x7fffffff)>>20) - 0x3ff; /* new k for n */
- t = 0.0;
- SET_HIGH_WORD(t, n & ~(0x000fffff>>k));
- n = ((n&0x000fffff)|0x00100000)>>(20-k);
- if (j < 0)
- n = -n;
- p_h -= t;
- }
- t = p_l + p_h;
- SET_LOW_WORD(t, 0);
- 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)/(t1-2.0) - (w + z*w);
- z = 1.0 - (r-z);
- GET_HIGH_WORD(j, z);
- j += n<<20;
- if ((j>>20) <= 0) /* subnormal output */
- z = scalbn(z,n);
- else
- SET_HIGH_WORD(z, j);
- return s*z;
-}
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