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Diffstat (limited to 'stmhal/math.c')
-rw-r--r-- | stmhal/math.c | 940 |
1 files changed, 0 insertions, 940 deletions
diff --git a/stmhal/math.c b/stmhal/math.c deleted file mode 100644 index 9f0d312488..0000000000 --- a/stmhal/math.c +++ /dev/null @@ -1,940 +0,0 @@ -/* - * This file is part of the Micro Python project, http://micropython.org/ - * - * The MIT License (MIT) - * - * Copyright (c) 2013, 2014 Damien P. George - * - * Permission is hereby granted, free of charge, to any person obtaining a copy - * of this software and associated documentation files (the "Software"), to deal - * in the Software without restriction, including without limitation the rights - * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell - * copies of the Software, and to permit persons to whom the Software is - * furnished to do so, subject to the following conditions: - * - * The above copyright notice and this permission notice shall be included in - * all copies or substantial portions of the Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE - * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, - * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN - * THE SOFTWARE. - */ - -#include <stdint.h> -#include <math.h> - -typedef float float_t; -typedef union { - float f; - struct { - uint64_t m : 23; - uint64_t e : 8; - uint64_t s : 1; - }; -} float_s_t; - -typedef union { - double d; - struct { - uint64_t m : 52; - uint64_t e : 11; - uint64_t s : 1; - }; -} double_s_t; - -double __attribute__((pcs("aapcs"))) __aeabi_i2d(int32_t x) { - return (float)x; -} - -double __attribute__((pcs("aapcs"))) __aeabi_f2d(float x) { - float_s_t fx={0}; - double_s_t dx={0}; - - fx.f = x; - dx.s = (fx.s); - dx.e = (fx.e-127+1023) & 0x7FF; - dx.m = fx.m; - dx.m <<=(52-23); // left justify - return dx.d; -} - -float __attribute__((pcs("aapcs"))) __aeabi_d2f(double x) { - float_s_t fx={0}; - double_s_t dx={0}; - - dx.d = x; - fx.s = (dx.s); - fx.e = (dx.e-1023+127) & 0xFF; - fx.m = (dx.m>>(52-23)); // right justify - return fx.f; -} - -double __aeabi_dmul(double x , double y) { - return 0.0; - -} - -float sqrtf(float x) { - asm volatile ( - "vsqrt.f32 %[r], %[x]\n" - : [r] "=t" (x) - : [x] "t" (x)); - return x; -} - -#ifndef NDEBUG -float copysignf(float x, float y) { - float_s_t fx={.f = x}; - float_s_t fy={.f = y}; - - // copy sign bit; - fx.s = fy.s; - - return fx.f; -} -#endif - -// some compilers define log2f in terms of logf -#ifdef log2f -#undef log2f -#endif -// some compilers have _M_LN2 defined in math.h, some don't -#ifndef _M_LN2 -#define _M_LN2 (0.69314718055994530942) -#endif -float log2f(float x) { return logf(x) / (float)_M_LN2; } - -static const float _M_LN10 = 2.30258509299404; // 0x40135d8e -float log10f(float x) { return logf(x) / (float)_M_LN10; } - -float tanhf(float x) { return sinhf(x) / coshf(x); } - -// TODO we need import these functions from some library (eg musl or newlib) -float acoshf(float x) { return 0.0; } -float asinhf(float x) { return 0.0; } -float atanhf(float x) { return 0.0; } -float tanf(float x) { return 0.0; } -float acosf(float x) { return 0.0; } -float asinf(float x) { return 0.0; } -float atanf(float x) { return 0.0; } -float atan2f(float x, float y) { return 0.0; } -float fmodf(float x, float y) { return 0.0; } -float tgammaf(float x) { return 0.0; } -float lgammaf(float x) { return 0.0; } -float erff(float x) { return 0.0; } -float erfcf(float x) { return 0.0; } -float modff(float x, float *y) { return 0.0; } -float frexpf(float x, int *exp) { return 0.0; } -float ldexpf(float x, int exp) { return 0.0; } - -/*****************************************************************************/ -/*****************************************************************************/ -// from musl-0.9.15 libm.h -/*****************************************************************************/ -/*****************************************************************************/ - -/* origin: FreeBSD /usr/src/lib/msun/src/math_private.h */ -/* - * ==================================================== - * 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. - * ==================================================== - */ - -#define FORCE_EVAL(x) do { \ - if (sizeof(x) == sizeof(float)) { \ - volatile float __x; \ - __x = (x); \ - (void)__x; \ - } else if (sizeof(x) == sizeof(double)) { \ - volatile double __x; \ - __x = (x); \ - (void)__x; \ - } else { \ - volatile long double __x; \ - __x = (x); \ - (void)__x; \ - } \ -} while(0) - -/* Get a 32 bit int from a float. */ -#define GET_FLOAT_WORD(w,d) \ -do { \ - union {float f; uint32_t i;} __u; \ - __u.f = (d); \ - (w) = __u.i; \ -} while (0) - -/* Set a float from a 32 bit int. */ -#define SET_FLOAT_WORD(d,w) \ -do { \ - union {float f; uint32_t i;} __u; \ - __u.i = (w); \ - (d) = __u.f; \ -} while (0) - -/*****************************************************************************/ -/*****************************************************************************/ -// __fpclassifyf from musl-0.9.15 -/*****************************************************************************/ -/*****************************************************************************/ - -int __fpclassifyf(float x) -{ - union {float f; uint32_t i;} u = {x}; - int e = u.i>>23 & 0xff; - if (!e) return u.i<<1 ? FP_SUBNORMAL : FP_ZERO; - if (e==0xff) return u.i<<9 ? FP_NAN : FP_INFINITE; - return FP_NORMAL; -} - -/*****************************************************************************/ -/*****************************************************************************/ -// scalbnf from musl-0.9.15 -/*****************************************************************************/ -/*****************************************************************************/ - -float scalbnf(float x, int n) -{ - union {float f; uint32_t i;} u; - float_t y = x; - - if (n > 127) { - y *= 0x1p127f; - n -= 127; - if (n > 127) { - y *= 0x1p127f; - n -= 127; - if (n > 127) - n = 127; - } - } else if (n < -126) { - y *= 0x1p-126f; - n += 126; - if (n < -126) { - y *= 0x1p-126f; - n += 126; - if (n < -126) - n = -126; - } - } - u.i = (uint32_t)(0x7f+n)<<23; - x = y * u.f; - return x; -} - -/*****************************************************************************/ -/*****************************************************************************/ -// powf from musl-0.9.15 -/*****************************************************************************/ -/*****************************************************************************/ - -/* origin: FreeBSD /usr/src/lib/msun/src/e_powf.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. - * ==================================================== - */ - -static const float -bp[] = {1.0, 1.5,}, -dp_h[] = { 0.0, 5.84960938e-01,}, /* 0x3f15c000 */ -dp_l[] = { 0.0, 1.56322085e-06,}, /* 0x35d1cfdc */ -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 = 9.6191406250e-01, /* 0x3f764000 =12b cp */ -cp_l = -1.1736857402e-04, /* 0xb8f623c6 =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; - - /* x**0 = 1, even if x is NaN */ - if (iy == 0) - return 1.0f; - /* 1**y = 1, even if y is NaN */ - if (hx == 0x3f800000) - return 1.0f; - /* NaN if either arg is NaN */ - 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) /* (-1)**+-inf is 1 */ - return 1.0f; - else if (ix > 0x3f800000) /* (|x|>1)**+-inf = inf,0 */ - return hy >= 0 ? y : 0.0f; - else if (ix != 0) /* (|x|<1)**+-inf = 0,inf if x!=0 */ - return hy >= 0 ? 0.0f: -y; - } - if (iy == 0x3f800000) /* y is +-1 */ - return hy >= 0 ? x : 1.0f/x; - if (hy == 0x40000000) /* y is 2 */ - return x*x; - 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) { /* x is +-0,+-inf,+-1 */ - z = ax; - if (hy < 0) /* z = (1/|x|) */ - z = 1.0f/z; - 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; - } - - sn = 1.0f; /* 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) */ - sn = -1.0f; - } - - /* |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)*(0.5f - t*(0.333333333333f - t*0.25f)); - 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) /* |x|<sqrt(3/2) */ - k = 0; - else if (j < 0x5db3d7) /* |x|<sqrt(3) */ - k = 1; - 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 = 1.0f/(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 = 3.0f + s2 + r; - GET_FLOAT_WORD(is, t_h); - SET_FLOAT_WORD(t_h, is & 0xfffff000); - t_l = r - ((t_h - 3.0f) - 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 */ // FIXME: check should be (uint32_t)j > 0xc3160000 - 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)/(t1-2.0f) - (w+z*w); - z = 1.0f - (r - z); - GET_FLOAT_WORD(j, z); - j += n<<23; - if ((j>>23) <= 0) /* subnormal output */ - z = scalbnf(z, n); - else - SET_FLOAT_WORD(z, j); - return sn*z; -} - -/*****************************************************************************/ -/*****************************************************************************/ -// expf from musl-0.9.15 -/*****************************************************************************/ -/*****************************************************************************/ - -/* origin: FreeBSD /usr/src/lib/msun/src/e_expf.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. - * ==================================================== - */ - -static const float -half[2] = {0.5,-0.5}, -ln2hi = 6.9314575195e-1f, /* 0x3f317200 */ -ln2lo = 1.4286067653e-6f, /* 0x35bfbe8e */ -invln2 = 1.4426950216e+0f, /* 0x3fb8aa3b */ -/* - * Domain [-0.34568, 0.34568], range ~[-4.278e-9, 4.447e-9]: - * |x*(exp(x)+1)/(exp(x)-1) - p(x)| < 2**-27.74 - */ -expf_P1 = 1.6666625440e-1f, /* 0xaaaa8f.0p-26 */ -expf_P2 = -2.7667332906e-3f; /* -0xb55215.0p-32 */ - -float expf(float x) -{ - float_t hi, lo, c, xx, y; - int k, sign; - uint32_t hx; - - GET_FLOAT_WORD(hx, x); - sign = hx >> 31; /* sign bit of x */ - hx &= 0x7fffffff; /* high word of |x| */ - - /* special cases */ - if (hx >= 0x42aeac50) { /* if |x| >= -87.33655f or NaN */ - if (hx >= 0x42b17218 && !sign) { /* x >= 88.722839f */ - /* overflow */ - x *= 0x1p127f; - return x; - } - if (sign) { - /* underflow */ - FORCE_EVAL(-0x1p-149f/x); - if (hx >= 0x42cff1b5) /* x <= -103.972084f */ - return 0; - } - } - - /* argument reduction */ - if (hx > 0x3eb17218) { /* if |x| > 0.5 ln2 */ - if (hx > 0x3f851592) /* if |x| > 1.5 ln2 */ - k = invln2*x + half[sign]; - else - k = 1 - sign - sign; - hi = x - k*ln2hi; /* k*ln2hi is exact here */ - lo = k*ln2lo; - x = hi - lo; - } else if (hx > 0x39000000) { /* |x| > 2**-14 */ - k = 0; - hi = x; - lo = 0; - } else { - /* raise inexact */ - FORCE_EVAL(0x1p127f + x); - return 1 + x; - } - - /* x is now in primary range */ - xx = x*x; - c = x - xx*(expf_P1+xx*expf_P2); - y = 1 + (x*c/(2-c) - lo + hi); - if (k == 0) - return y; - return scalbnf(y, k); -} - -/*****************************************************************************/ -/*****************************************************************************/ -// expm1f from musl-0.9.15 -/*****************************************************************************/ -/*****************************************************************************/ - -/* origin: FreeBSD /usr/src/lib/msun/src/s_expm1f.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. - * ==================================================== - */ - -static const float -o_threshold = 8.8721679688e+01, /* 0x42b17180 */ -ln2_hi = 6.9313812256e-01, /* 0x3f317180 */ -ln2_lo = 9.0580006145e-06, /* 0x3717f7d1 */ -//invln2 = 1.4426950216e+00, /* 0x3fb8aa3b */ -/* - * Domain [-0.34568, 0.34568], range ~[-6.694e-10, 6.696e-10]: - * |6 / x * (1 + 2 * (1 / (exp(x) - 1) - 1 / x)) - q(x)| < 2**-30.04 - * Scaled coefficients: Qn_here = 2**n * Qn_for_q (see s_expm1.c): - */ -Q1 = -3.3333212137e-2, /* -0x888868.0p-28 */ -Q2 = 1.5807170421e-3; /* 0xcf3010.0p-33 */ - -float expm1f(float x) -{ - float_t y,hi,lo,c,t,e,hxs,hfx,r1,twopk; - union {float f; uint32_t i;} u = {x}; - uint32_t hx = u.i & 0x7fffffff; - int k, sign = u.i >> 31; - - /* filter out huge and non-finite argument */ - if (hx >= 0x4195b844) { /* if |x|>=27*ln2 */ - if (hx > 0x7f800000) /* NaN */ - return x; - if (sign) - return -1; - if (x > o_threshold) { - x *= 0x1p127f; - return x; - } - } - - /* argument reduction */ - if (hx > 0x3eb17218) { /* if |x| > 0.5 ln2 */ - if (hx < 0x3F851592) { /* and |x| < 1.5 ln2 */ - if (!sign) { - hi = x - ln2_hi; - lo = ln2_lo; - k = 1; - } else { - hi = x + ln2_hi; - lo = -ln2_lo; - k = -1; - } - } else { - k = invln2*x + (sign ? -0.5f : 0.5f); - t = k; - hi = x - t*ln2_hi; /* t*ln2_hi is exact here */ - lo = t*ln2_lo; - } - x = hi-lo; - c = (hi-x)-lo; - } else if (hx < 0x33000000) { /* when |x|<2**-25, return x */ - if (hx < 0x00800000) - FORCE_EVAL(x*x); - return x; - } else - k = 0; - - /* x is now in primary range */ - hfx = 0.5f*x; - hxs = x*hfx; - r1 = 1.0f+hxs*(Q1+hxs*Q2); - t = 3.0f - r1*hfx; - e = hxs*((r1-t)/(6.0f - x*t)); - if (k == 0) /* c is 0 */ - return x - (x*e-hxs); - e = x*(e-c) - c; - e -= hxs; - /* exp(x) ~ 2^k (x_reduced - e + 1) */ - if (k == -1) - return 0.5f*(x-e) - 0.5f; - if (k == 1) { - if (x < -0.25f) - return -2.0f*(e-(x+0.5f)); - return 1.0f + 2.0f*(x-e); - } - u.i = (0x7f+k)<<23; /* 2^k */ - twopk = u.f; - if (k < 0 || k > 56) { /* suffice to return exp(x)-1 */ - y = x - e + 1.0f; - if (k == 128) - y = y*2.0f*0x1p127f; - else - y = y*twopk; - return y - 1.0f; - } - u.i = (0x7f-k)<<23; /* 2^-k */ - if (k < 23) - y = (x-e+(1-u.f))*twopk; - else - y = (x-(e+u.f)+1)*twopk; - return y; -} - -/*****************************************************************************/ -/*****************************************************************************/ -// __expo2f from musl-0.9.15 -/*****************************************************************************/ -/*****************************************************************************/ - -/* k is such that k*ln2 has minimal relative error and x - kln2 > log(FLT_MIN) */ -static const int k = 235; -static const float kln2 = 0x1.45c778p+7f; - -/* expf(x)/2 for x >= log(FLT_MAX), slightly better than 0.5f*expf(x/2)*expf(x/2) */ -float __expo2f(float x) -{ - float scale; - - /* note that k is odd and scale*scale overflows */ - SET_FLOAT_WORD(scale, (uint32_t)(0x7f + k/2) << 23); - /* exp(x - k ln2) * 2**(k-1) */ - return expf(x - kln2) * scale * scale; -} - -/*****************************************************************************/ -/*****************************************************************************/ -// logf from musl-0.9.15 -/*****************************************************************************/ -/*****************************************************************************/ - -/* origin: FreeBSD /usr/src/lib/msun/src/e_logf.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. - * ==================================================== - */ - -static const float -/* |(log(1+s)-log(1-s))/s - Lg(s)| < 2**-34.24 (~[-4.95e-11, 4.97e-11]). */ -Lg1 = 0xaaaaaa.0p-24, /* 0.66666662693 */ -Lg2 = 0xccce13.0p-25, /* 0.40000972152 */ -Lg3 = 0x91e9ee.0p-25, /* 0.28498786688 */ -Lg4 = 0xf89e26.0p-26; /* 0.24279078841 */ - -float logf(float x) -{ - union {float f; uint32_t i;} u = {x}; - float_t hfsq,f,s,z,R,w,t1,t2,dk; - uint32_t ix; - int k; - - ix = u.i; - k = 0; - if (ix < 0x00800000 || ix>>31) { /* x < 2**-126 */ - if (ix<<1 == 0) - return -1/(x*x); /* log(+-0)=-inf */ - if (ix>>31) - return (x-x)/0.0f; /* log(-#) = NaN */ - /* subnormal number, scale up x */ - k -= 25; - x *= 0x1p25f; - u.f = x; - ix = u.i; - } else if (ix >= 0x7f800000) { - return x; - } else if (ix == 0x3f800000) - return 0; - - /* reduce x into [sqrt(2)/2, sqrt(2)] */ - ix += 0x3f800000 - 0x3f3504f3; - k += (int)(ix>>23) - 0x7f; - ix = (ix&0x007fffff) + 0x3f3504f3; - u.i = ix; - x = u.f; - - f = x - 1.0f; - s = f/(2.0f + f); - z = s*s; - w = z*z; - t1= w*(Lg2+w*Lg4); - t2= z*(Lg1+w*Lg3); - R = t2 + t1; - hfsq = 0.5f*f*f; - dk = k; - return s*(hfsq+R) + dk*ln2_lo - hfsq + f + dk*ln2_hi; -} - -/*****************************************************************************/ -/*****************************************************************************/ -// coshf from musl-0.9.15 -/*****************************************************************************/ -/*****************************************************************************/ - -float coshf(float x) -{ - union {float f; uint32_t i;} u = {.f = x}; - uint32_t w; - float t; - - /* |x| */ - u.i &= 0x7fffffff; - x = u.f; - w = u.i; - - /* |x| < log(2) */ - if (w < 0x3f317217) { - if (w < 0x3f800000 - (12<<23)) { - FORCE_EVAL(x + 0x1p120f); - return 1; - } - t = expm1f(x); - return 1 + t*t/(2*(1+t)); - } - - /* |x| < log(FLT_MAX) */ - if (w < 0x42b17217) { - t = expf(x); - return 0.5f*(t + 1/t); - } - - /* |x| > log(FLT_MAX) or nan */ - t = __expo2f(x); - return t; -} - -/*****************************************************************************/ -/*****************************************************************************/ -// sinhf from musl-0.9.15 -/*****************************************************************************/ -/*****************************************************************************/ - -float sinhf(float x) -{ - union {float f; uint32_t i;} u = {.f = x}; - uint32_t w; - float t, h, absx; - - h = 0.5; - if (u.i >> 31) - h = -h; - /* |x| */ - u.i &= 0x7fffffff; - absx = u.f; - w = u.i; - - /* |x| < log(FLT_MAX) */ - if (w < 0x42b17217) { - t = expm1f(absx); - if (w < 0x3f800000) { - if (w < 0x3f800000 - (12<<23)) - return x; - return h*(2*t - t*t/(t+1)); - } - return h*(t + t/(t+1)); - } - - /* |x| > logf(FLT_MAX) or nan */ - t = 2*h*__expo2f(absx); - return t; -} - -/*****************************************************************************/ -/*****************************************************************************/ -// ceilf, floorf and truncf from musl-0.9.15 -/*****************************************************************************/ -/*****************************************************************************/ - -float ceilf(float x) -{ - union {float f; uint32_t i;} u = {x}; - int e = (int)(u.i >> 23 & 0xff) - 0x7f; - uint32_t m; - - if (e >= 23) - return x; - if (e >= 0) { - m = 0x007fffff >> e; - if ((u.i & m) == 0) - return x; - FORCE_EVAL(x + 0x1p120f); - if (u.i >> 31 == 0) - u.i += m; - u.i &= ~m; - } else { - FORCE_EVAL(x + 0x1p120f); - if (u.i >> 31) - u.f = -0.0; - else if (u.i << 1) - u.f = 1.0; - } - return u.f; -} - -float floorf(float x) -{ - union {float f; uint32_t i;} u = {x}; - int e = (int)(u.i >> 23 & 0xff) - 0x7f; - uint32_t m; - - if (e >= 23) - return x; - if (e >= 0) { - m = 0x007fffff >> e; - if ((u.i & m) == 0) - return x; - FORCE_EVAL(x + 0x1p120f); - if (u.i >> 31) - u.i += m; - u.i &= ~m; - } else { - FORCE_EVAL(x + 0x1p120f); - if (u.i >> 31 == 0) - u.i = 0; - else if (u.i << 1) - u.f = -1.0; - } - return u.f; -} - -float truncf(float x) -{ - union {float f; uint32_t i;} u = {x}; - int e = (int)(u.i >> 23 & 0xff) - 0x7f + 9; - uint32_t m; - - if (e >= 23 + 9) - return x; - if (e < 9) - e = 1; - m = -1U >> e; - if ((u.i & m) == 0) - return x; - FORCE_EVAL(x + 0x1p120f); - u.i &= ~m; - return u.f; -} |