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-rw-r--r--3rdparty/SDL2/src/libm/e_log.c167
1 files changed, 0 insertions, 167 deletions
diff --git a/3rdparty/SDL2/src/libm/e_log.c b/3rdparty/SDL2/src/libm/e_log.c
deleted file mode 100644
index da64138cd18..00000000000
--- a/3rdparty/SDL2/src/libm/e_log.c
+++ /dev/null
@@ -1,167 +0,0 @@
-/* @(#)e_log.c 5.1 93/09/24 */
-/*
- * ====================================================
- * 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.
- * ====================================================
- */
-
-#if defined(LIBM_SCCS) && !defined(lint)
-static const char rcsid[] =
- "$NetBSD: e_log.c,v 1.8 1995/05/10 20:45:49 jtc Exp $";
-#endif
-
-/* __ieee754_log(x)
- * Return the logrithm of x
- *
- * Method :
- * 1. Argument Reduction: find k and f such that
- * x = 2^k * (1+f),
- * where sqrt(2)/2 < 1+f < sqrt(2) .
- *
- * 2. Approximation of log(1+f).
- * Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s)
- * = 2s + 2/3 s**3 + 2/5 s**5 + .....,
- * = 2s + s*R
- * We use a special Reme algorithm on [0,0.1716] to generate
- * a polynomial of degree 14 to approximate R The maximum error
- * of this polynomial approximation is bounded by 2**-58.45. In
- * other words,
- * 2 4 6 8 10 12 14
- * R(z) ~ Lg1*s +Lg2*s +Lg3*s +Lg4*s +Lg5*s +Lg6*s +Lg7*s
- * (the values of Lg1 to Lg7 are listed in the program)
- * and
- * | 2 14 | -58.45
- * | Lg1*s +...+Lg7*s - R(z) | <= 2
- * | |
- * Note that 2s = f - s*f = f - hfsq + s*hfsq, where hfsq = f*f/2.
- * In order to guarantee error in log below 1ulp, we compute log
- * by
- * log(1+f) = f - s*(f - R) (if f is not too large)
- * log(1+f) = f - (hfsq - s*(hfsq+R)). (better accuracy)
- *
- * 3. Finally, log(x) = k*ln2 + log(1+f).
- * = k*ln2_hi+(f-(hfsq-(s*(hfsq+R)+k*ln2_lo)))
- * Here ln2 is split into two floating point number:
- * ln2_hi + ln2_lo,
- * where n*ln2_hi is always exact for |n| < 2000.
- *
- * Special cases:
- * log(x) is NaN with signal if x < 0 (including -INF) ;
- * log(+INF) is +INF; log(0) is -INF with signal;
- * log(NaN) is that NaN with no signal.
- *
- * Accuracy:
- * according to an error analysis, the error is always less than
- * 1 ulp (unit in the last place).
- *
- * 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 "math_libm.h"
-#include "math_private.h"
-
-#ifdef __STDC__
-static const double
-#else
-static double
-#endif
- ln2_hi = 6.93147180369123816490e-01, /* 3fe62e42 fee00000 */
- ln2_lo = 1.90821492927058770002e-10, /* 3dea39ef 35793c76 */
- two54 = 1.80143985094819840000e+16, /* 43500000 00000000 */
- Lg1 = 6.666666666666735130e-01, /* 3FE55555 55555593 */
- Lg2 = 3.999999999940941908e-01, /* 3FD99999 9997FA04 */
- Lg3 = 2.857142874366239149e-01, /* 3FD24924 94229359 */
- Lg4 = 2.222219843214978396e-01, /* 3FCC71C5 1D8E78AF */
- Lg5 = 1.818357216161805012e-01, /* 3FC74664 96CB03DE */
- Lg6 = 1.531383769920937332e-01, /* 3FC39A09 D078C69F */
- Lg7 = 1.479819860511658591e-01; /* 3FC2F112 DF3E5244 */
-
-#ifdef __STDC__
-static const double zero = 0.0;
-#else
-static double zero = 0.0;
-#endif
-
-#ifdef __STDC__
-double attribute_hidden
-__ieee754_log(double x)
-#else
-double attribute_hidden
-__ieee754_log(x)
- double x;
-#endif
-{
- double hfsq, f, s, z, R, w, t1, t2, dk;
- int32_t k, hx, i, j;
- u_int32_t lx;
-
- EXTRACT_WORDS(hx, lx, x);
-
- k = 0;
- if (hx < 0x00100000) { /* x < 2**-1022 */
- if (((hx & 0x7fffffff) | lx) == 0)
- return -two54 / zero; /* log(+-0)=-inf */
- if (hx < 0)
- return (x - x) / zero; /* log(-#) = NaN */
- k -= 54;
- x *= two54; /* subnormal number, scale up x */
- GET_HIGH_WORD(hx, x);
- }
- if (hx >= 0x7ff00000)
- return x + x;
- k += (hx >> 20) - 1023;
- hx &= 0x000fffff;
- i = (hx + 0x95f64) & 0x100000;
- SET_HIGH_WORD(x, hx | (i ^ 0x3ff00000)); /* normalize x or x/2 */
- k += (i >> 20);
- f = x - 1.0;
- if ((0x000fffff & (2 + hx)) < 3) { /* |f| < 2**-20 */
- if (f == zero) {
- if (k == 0)
- return zero;
- else {
- dk = (double) k;
- return dk * ln2_hi + dk * ln2_lo;
- }
- }
- R = f * f * (0.5 - 0.33333333333333333 * f);
- if (k == 0)
- return f - R;
- else {
- dk = (double) k;
- return dk * ln2_hi - ((R - dk * ln2_lo) - f);
- }
- }
- s = f / (2.0 + f);
- dk = (double) k;
- z = s * s;
- i = hx - 0x6147a;
- w = z * z;
- j = 0x6b851 - hx;
- 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 = 0.5 * f * f;
- if (k == 0)
- return f - (hfsq - s * (hfsq + R));
- else
- return dk * ln2_hi - ((hfsq - (s * (hfsq + R) + dk * ln2_lo)) -
- f);
- } else {
- if (k == 0)
- return f - s * (f - R);
- else
- return dk * ln2_hi - ((s * (f - R) - dk * ln2_lo) - f);
- }
-}