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authorchai <chaifix@163.com>2019-05-11 22:54:56 +0800
committerchai <chaifix@163.com>2019-05-11 22:54:56 +0800
commit9645be0af1b1d5cb0ad5892d5464e1b23c51b550 (patch)
tree129c716bed8e93312421c3adb2f8e7c4f811602d /source/3rd-party/SDL2/src/libm
Diffstat (limited to 'source/3rd-party/SDL2/src/libm')
-rw-r--r--source/3rd-party/SDL2/src/libm/e_atan2.c134
-rw-r--r--source/3rd-party/SDL2/src/libm/e_exp.c187
-rw-r--r--source/3rd-party/SDL2/src/libm/e_fmod.c144
-rw-r--r--source/3rd-party/SDL2/src/libm/e_log.c152
-rw-r--r--source/3rd-party/SDL2/src/libm/e_log10.c106
-rw-r--r--source/3rd-party/SDL2/src/libm/e_pow.c343
-rw-r--r--source/3rd-party/SDL2/src/libm/e_rem_pio2.c161
-rw-r--r--source/3rd-party/SDL2/src/libm/e_sqrt.c457
-rw-r--r--source/3rd-party/SDL2/src/libm/k_cos.c82
-rw-r--r--source/3rd-party/SDL2/src/libm/k_rem_pio2.c317
-rw-r--r--source/3rd-party/SDL2/src/libm/k_sin.c65
-rw-r--r--source/3rd-party/SDL2/src/libm/k_tan.c118
-rw-r--r--source/3rd-party/SDL2/src/libm/math_libm.h47
-rw-r--r--source/3rd-party/SDL2/src/libm/math_private.h227
-rw-r--r--source/3rd-party/SDL2/src/libm/s_atan.c114
-rw-r--r--source/3rd-party/SDL2/src/libm/s_copysign.c29
-rw-r--r--source/3rd-party/SDL2/src/libm/s_cos.c73
-rw-r--r--source/3rd-party/SDL2/src/libm/s_fabs.c29
-rw-r--r--source/3rd-party/SDL2/src/libm/s_floor.c71
-rw-r--r--source/3rd-party/SDL2/src/libm/s_scalbn.c69
-rw-r--r--source/3rd-party/SDL2/src/libm/s_sin.c73
-rw-r--r--source/3rd-party/SDL2/src/libm/s_tan.c67
22 files changed, 3065 insertions, 0 deletions
diff --git a/source/3rd-party/SDL2/src/libm/e_atan2.c b/source/3rd-party/SDL2/src/libm/e_atan2.c
new file mode 100644
index 0000000..32b9725
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/e_atan2.c
@@ -0,0 +1,134 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* __ieee754_atan2(y,x)
+ * Method :
+ * 1. Reduce y to positive by atan2(y,x)=-atan2(-y,x).
+ * 2. Reduce x to positive by (if x and y are unexceptional):
+ * ARG (x+iy) = arctan(y/x) ... if x > 0,
+ * ARG (x+iy) = pi - arctan[y/(-x)] ... if x < 0,
+ *
+ * Special cases:
+ *
+ * ATAN2((anything), NaN ) is NaN;
+ * ATAN2(NAN , (anything) ) is NaN;
+ * ATAN2(+-0, +(anything but NaN)) is +-0 ;
+ * ATAN2(+-0, -(anything but NaN)) is +-pi ;
+ * ATAN2(+-(anything but 0 and NaN), 0) is +-pi/2;
+ * ATAN2(+-(anything but INF and NaN), +INF) is +-0 ;
+ * ATAN2(+-(anything but INF and NaN), -INF) is +-pi;
+ * ATAN2(+-INF,+INF ) is +-pi/4 ;
+ * ATAN2(+-INF,-INF ) is +-3pi/4;
+ * ATAN2(+-INF, (anything but,0,NaN, and INF)) is +-pi/2;
+ *
+ * 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"
+
+static const double
+tiny = 1.0e-300,
+zero = 0.0,
+pi_o_4 = 7.8539816339744827900E-01, /* 0x3FE921FB, 0x54442D18 */
+pi_o_2 = 1.5707963267948965580E+00, /* 0x3FF921FB, 0x54442D18 */
+pi = 3.1415926535897931160E+00, /* 0x400921FB, 0x54442D18 */
+pi_lo = 1.2246467991473531772E-16; /* 0x3CA1A626, 0x33145C07 */
+
+double attribute_hidden __ieee754_atan2(double y, double x)
+{
+ double z;
+ int32_t k,m,hx,hy,ix,iy;
+ u_int32_t lx,ly;
+
+ EXTRACT_WORDS(hx,lx,x);
+ ix = hx&0x7fffffff;
+ EXTRACT_WORDS(hy,ly,y);
+ iy = hy&0x7fffffff;
+ if(((ix|((lx|-(int32_t)lx)>>31))>0x7ff00000)||
+ ((iy|((ly|-(int32_t)ly)>>31))>0x7ff00000)) /* x or y is NaN */
+ return x+y;
+ if(((hx-0x3ff00000)|lx)==0) return atan(y); /* x=1.0 */
+ m = ((hy>>31)&1)|((hx>>30)&2); /* 2*sign(x)+sign(y) */
+
+ /* when y = 0 */
+ if((iy|ly)==0) {
+ switch(m) {
+ case 0:
+ case 1: return y; /* atan(+-0,+anything)=+-0 */
+ case 2: return pi+tiny;/* atan(+0,-anything) = pi */
+ case 3: return -pi-tiny;/* atan(-0,-anything) =-pi */
+ }
+ }
+ /* when x = 0 */
+ if((ix|lx)==0) return (hy<0)? -pi_o_2-tiny: pi_o_2+tiny;
+
+ /* when x is INF */
+ if(ix==0x7ff00000) {
+ if(iy==0x7ff00000) {
+ switch(m) {
+ case 0: return pi_o_4+tiny;/* atan(+INF,+INF) */
+ case 1: return -pi_o_4-tiny;/* atan(-INF,+INF) */
+ case 2: return 3.0*pi_o_4+tiny;/*atan(+INF,-INF)*/
+ case 3: return -3.0*pi_o_4-tiny;/*atan(-INF,-INF)*/
+ }
+ } else {
+ switch(m) {
+ case 0: return zero ; /* atan(+...,+INF) */
+ case 1: return -zero ; /* atan(-...,+INF) */
+ case 2: return pi+tiny ; /* atan(+...,-INF) */
+ case 3: return -pi-tiny ; /* atan(-...,-INF) */
+ }
+ }
+ }
+ /* when y is INF */
+ if(iy==0x7ff00000) return (hy<0)? -pi_o_2-tiny: pi_o_2+tiny;
+
+ /* compute y/x */
+ k = (iy-ix)>>20;
+ if(k > 60) z=pi_o_2+0.5*pi_lo; /* |y/x| > 2**60 */
+ else if(hx<0&&k<-60) z=0.0; /* |y|/x < -2**60 */
+ else z=atan(fabs(y/x)); /* safe to do y/x */
+ switch (m) {
+ case 0: return z ; /* atan(+,+) */
+ case 1: {
+ u_int32_t zh;
+ GET_HIGH_WORD(zh,z);
+ SET_HIGH_WORD(z,zh ^ 0x80000000);
+ }
+ return z ; /* atan(-,+) */
+ case 2: return pi-(z-pi_lo);/* atan(+,-) */
+ default: /* case 3 */
+ return (z-pi_lo)-pi;/* atan(-,-) */
+ }
+}
+
+/*
+ * wrapper atan2(y,x)
+ */
+#ifndef _IEEE_LIBM
+double atan2(double y, double x)
+{
+ double z = __ieee754_atan2(y, x);
+ if (_LIB_VERSION == _IEEE_ || isnan(x) || isnan(y))
+ return z;
+ if (x == 0.0 && y == 0.0)
+ return __kernel_standard(y,x,3); /* atan2(+-0,+-0) */
+ return z;
+}
+#else
+strong_alias(__ieee754_atan2, atan2)
+#endif
+libm_hidden_def(atan2)
diff --git a/source/3rd-party/SDL2/src/libm/e_exp.c b/source/3rd-party/SDL2/src/libm/e_exp.c
new file mode 100644
index 0000000..d8cd4a4
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/e_exp.c
@@ -0,0 +1,187 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* __ieee754_exp(x)
+ * Returns the exponential of x.
+ *
+ * Method
+ * 1. Argument reduction:
+ * Reduce x to an r so that |r| <= 0.5*ln2 ~ 0.34658.
+ * Given x, find r and integer k such that
+ *
+ * x = k*ln2 + r, |r| <= 0.5*ln2.
+ *
+ * Here r will be represented as r = hi-lo for better
+ * accuracy.
+ *
+ * 2. Approximation of exp(r) by a special rational function on
+ * the interval [0,0.34658]:
+ * Write
+ * R(r**2) = r*(exp(r)+1)/(exp(r)-1) = 2 + r*r/6 - r**4/360 + ...
+ * We use a special Reme algorithm on [0,0.34658] to generate
+ * a polynomial of degree 5 to approximate R. The maximum error
+ * of this polynomial approximation is bounded by 2**-59. In
+ * other words,
+ * R(z) ~ 2.0 + P1*z + P2*z**2 + P3*z**3 + P4*z**4 + P5*z**5
+ * (where z=r*r, and the values of P1 to P5 are listed below)
+ * and
+ * | 5 | -59
+ * | 2.0+P1*z+...+P5*z - R(z) | <= 2
+ * | |
+ * The computation of exp(r) thus becomes
+ * 2*r
+ * exp(r) = 1 + -------
+ * R - r
+ * r*R1(r)
+ * = 1 + r + ----------- (for better accuracy)
+ * 2 - R1(r)
+ * where
+ * 2 4 10
+ * R1(r) = r - (P1*r + P2*r + ... + P5*r ).
+ *
+ * 3. Scale back to obtain exp(x):
+ * From step 1, we have
+ * exp(x) = 2^k * exp(r)
+ *
+ * Special cases:
+ * exp(INF) is INF, exp(NaN) is NaN;
+ * exp(-INF) is 0, and
+ * for finite argument, only exp(0)=1 is exact.
+ *
+ * Accuracy:
+ * according to an error analysis, the error is always less than
+ * 1 ulp (unit in the last place).
+ *
+ * Misc. info.
+ * For IEEE double
+ * if x > 7.09782712893383973096e+02 then exp(x) overflow
+ * if x < -7.45133219101941108420e+02 then exp(x) underflow
+ *
+ * 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"
+
+static const double
+one = 1.0,
+halF[2] = {0.5,-0.5,},
+huge = 1.0e+300,
+twom1000= 9.33263618503218878990e-302, /* 2**-1000=0x01700000,0*/
+o_threshold= 7.09782712893383973096e+02, /* 0x40862E42, 0xFEFA39EF */
+u_threshold= -7.45133219101941108420e+02, /* 0xc0874910, 0xD52D3051 */
+ln2HI[2] ={ 6.93147180369123816490e-01, /* 0x3fe62e42, 0xfee00000 */
+ -6.93147180369123816490e-01,},/* 0xbfe62e42, 0xfee00000 */
+ln2LO[2] ={ 1.90821492927058770002e-10, /* 0x3dea39ef, 0x35793c76 */
+ -1.90821492927058770002e-10,},/* 0xbdea39ef, 0x35793c76 */
+invln2 = 1.44269504088896338700e+00, /* 0x3ff71547, 0x652b82fe */
+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 */
+
+double __ieee754_exp(double x) /* default IEEE double exp */
+{
+ double y;
+ double hi = 0.0;
+ double lo = 0.0;
+ double c;
+ double t;
+ int32_t k=0;
+ int32_t xsb;
+ u_int32_t hx;
+
+ GET_HIGH_WORD(hx,x);
+ xsb = (hx>>31)&1; /* sign bit of x */
+ hx &= 0x7fffffff; /* high word of |x| */
+
+ /* filter out non-finite argument */
+ if(hx >= 0x40862E42) { /* if |x|>=709.78... */
+ if(hx>=0x7ff00000) {
+ u_int32_t lx;
+ GET_LOW_WORD(lx,x);
+ if(((hx&0xfffff)|lx)!=0)
+ return x+x; /* NaN */
+ else return (xsb==0)? x:0.0; /* exp(+-inf)={inf,0} */
+ }
+ #if 1
+ if(x > o_threshold) return huge*huge; /* overflow */
+ #else /* !!! FIXME: check this: "huge * huge" is a compiler warning, maybe they wanted +Inf? */
+ if(x > o_threshold) return INFINITY; /* overflow */
+ #endif
+
+ if(x < u_threshold) return twom1000*twom1000; /* underflow */
+ }
+
+ /* argument reduction */
+ if(hx > 0x3fd62e42) { /* if |x| > 0.5 ln2 */
+ if(hx < 0x3FF0A2B2) { /* and |x| < 1.5 ln2 */
+ hi = x-ln2HI[xsb]; lo=ln2LO[xsb]; k = 1-xsb-xsb;
+ } else {
+ k = (int32_t) (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 < 0x3e300000) { /* 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-2.0)-x);
+ else y = one-((lo-(x*c)/(2.0-c))-hi);
+ if(k >= -1021) {
+ u_int32_t hy;
+ GET_HIGH_WORD(hy,y);
+ SET_HIGH_WORD(y,hy+(k<<20)); /* add k to y's exponent */
+ return y;
+ } else {
+ u_int32_t hy;
+ GET_HIGH_WORD(hy,y);
+ SET_HIGH_WORD(y,hy+((k+1000)<<20)); /* add k to y's exponent */
+ return y*twom1000;
+ }
+}
+
+/*
+ * wrapper exp(x)
+ */
+#ifndef _IEEE_LIBM
+double exp(double x)
+{
+ static const double o_threshold = 7.09782712893383973096e+02; /* 0x40862E42, 0xFEFA39EF */
+ static const double u_threshold = -7.45133219101941108420e+02; /* 0xc0874910, 0xD52D3051 */
+
+ double z = __ieee754_exp(x);
+ if (_LIB_VERSION == _IEEE_)
+ return z;
+ if (isfinite(x)) {
+ if (x > o_threshold)
+ return __kernel_standard(x, x, 6); /* exp overflow */
+ if (x < u_threshold)
+ return __kernel_standard(x, x, 7); /* exp underflow */
+ }
+ return z;
+}
+#else
+strong_alias(__ieee754_exp, exp)
+#endif
+libm_hidden_def(exp)
diff --git a/source/3rd-party/SDL2/src/libm/e_fmod.c b/source/3rd-party/SDL2/src/libm/e_fmod.c
new file mode 100644
index 0000000..fd8bacb
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/e_fmod.c
@@ -0,0 +1,144 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/*
+ * __ieee754_fmod(x,y)
+ * Return x mod y in exact arithmetic
+ * Method: shift and subtract
+ */
+
+#include "math_libm.h"
+#include "math_private.h"
+
+static const double one = 1.0, Zero[] = {0.0, -0.0,};
+
+double attribute_hidden __ieee754_fmod(double x, double y)
+{
+ int32_t n,hx,hy,hz,ix,iy,sx,i;
+ u_int32_t lx,ly,lz;
+
+ EXTRACT_WORDS(hx,lx,x);
+ EXTRACT_WORDS(hy,ly,y);
+ sx = hx&0x80000000; /* sign of x */
+ hx ^=sx; /* |x| */
+ hy &= 0x7fffffff; /* |y| */
+
+ /* purge off exception values */
+ if((hy|ly)==0||(hx>=0x7ff00000)|| /* y=0,or x not finite */
+ ((hy|((ly|-(int32_t)ly)>>31))>0x7ff00000)) /* or y is NaN */
+ return (x*y)/(x*y);
+ if(hx<=hy) {
+ if((hx<hy)||(lx<ly)) return x; /* |x|<|y| return x */
+ if(lx==ly)
+ return Zero[(u_int32_t)sx>>31]; /* |x|=|y| return x*0*/
+ }
+
+ /* determine ix = ilogb(x) */
+ if(hx<0x00100000) { /* subnormal x */
+ if(hx==0) {
+ for (ix = -1043, i=lx; i>0; i<<=1) ix -=1;
+ } else {
+ for (ix = -1022,i=(hx<<11); i>0; i<<=1) ix -=1;
+ }
+ } else ix = (hx>>20)-1023;
+
+ /* determine iy = ilogb(y) */
+ if(hy<0x00100000) { /* subnormal y */
+ if(hy==0) {
+ for (iy = -1043, i=ly; i>0; i<<=1) iy -=1;
+ } else {
+ for (iy = -1022,i=(hy<<11); i>0; i<<=1) iy -=1;
+ }
+ } else iy = (hy>>20)-1023;
+
+ /* set up {hx,lx}, {hy,ly} and align y to x */
+ if(ix >= -1022)
+ hx = 0x00100000|(0x000fffff&hx);
+ else { /* subnormal x, shift x to normal */
+ n = -1022-ix;
+ if(n<=31) {
+ hx = (hx<<n)|(lx>>(32-n));
+ lx <<= n;
+ } else {
+ hx = lx<<(n-32);
+ lx = 0;
+ }
+ }
+ if(iy >= -1022)
+ hy = 0x00100000|(0x000fffff&hy);
+ else { /* subnormal y, shift y to normal */
+ n = -1022-iy;
+ if(n<=31) {
+ hy = (hy<<n)|(ly>>(32-n));
+ ly <<= n;
+ } else {
+ hy = ly<<(n-32);
+ ly = 0;
+ }
+ }
+
+ /* fix point fmod */
+ n = ix - iy;
+ while(n--) {
+ hz=hx-hy;lz=lx-ly; if(lx<ly) hz -= 1;
+ if(hz<0){hx = hx+hx+(lx>>31); lx = lx+lx;}
+ else {
+ if((hz|lz)==0) /* return sign(x)*0 */
+ return Zero[(u_int32_t)sx>>31];
+ hx = hz+hz+(lz>>31); lx = lz+lz;
+ }
+ }
+ hz=hx-hy;lz=lx-ly; if(lx<ly) hz -= 1;
+ if(hz>=0) {hx=hz;lx=lz;}
+
+ /* convert back to floating value and restore the sign */
+ if((hx|lx)==0) /* return sign(x)*0 */
+ return Zero[(u_int32_t)sx>>31];
+ while(hx<0x00100000) { /* normalize x */
+ hx = hx+hx+(lx>>31); lx = lx+lx;
+ iy -= 1;
+ }
+ if(iy>= -1022) { /* normalize output */
+ hx = ((hx-0x00100000)|((iy+1023)<<20));
+ INSERT_WORDS(x,hx|sx,lx);
+ } else { /* subnormal output */
+ n = -1022 - iy;
+ if(n<=20) {
+ lx = (lx>>n)|((u_int32_t)hx<<(32-n));
+ hx >>= n;
+ } else if (n<=31) {
+ lx = (hx<<(32-n))|(lx>>n); hx = sx;
+ } else {
+ lx = hx>>(n-32); hx = sx;
+ }
+ INSERT_WORDS(x,hx|sx,lx);
+ x *= one; /* create necessary signal */
+ }
+ return x; /* exact output */
+}
+
+/*
+ * wrapper fmod(x,y)
+ */
+#ifndef _IEEE_LIBM
+double fmod(double x, double y)
+{
+ double z = __ieee754_fmod(x, y);
+ if (_LIB_VERSION == _IEEE_ || isnan(y) || isnan(x))
+ return z;
+ if (y == 0.0)
+ return __kernel_standard(x, y, 27); /* fmod(x,0) */
+ return z;
+}
+#else
+strong_alias(__ieee754_fmod, fmod)
+#endif
+libm_hidden_def(fmod)
diff --git a/source/3rd-party/SDL2/src/libm/e_log.c b/source/3rd-party/SDL2/src/libm/e_log.c
new file mode 100644
index 0000000..208df81
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/e_log.c
@@ -0,0 +1,152 @@
+/*
+ * ====================================================
+ * 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(_MSC_VER) /* Handle Microsoft VC++ compiler specifics. */
+/* C4723: potential divide by zero. */
+#pragma warning ( disable : 4723 )
+#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"
+
+static const double
+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 */
+
+static const double zero = 0.0;
+
+double attribute_hidden __ieee754_log(double x)
+{
+ 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);
+ }
+}
+
+/*
+ * wrapper log(x)
+ */
+#ifndef _IEEE_LIBM
+double log(double x)
+{
+ double z = __ieee754_log(x);
+ if (_LIB_VERSION == _IEEE_ || isnan(x) || x > 0.0)
+ return z;
+ if (x == 0.0)
+ return __kernel_standard(x, x, 16); /* log(0) */
+ return __kernel_standard(x, x, 17); /* log(x<0) */
+}
+#else
+strong_alias(__ieee754_log, log)
+#endif
+libm_hidden_def(log)
diff --git a/source/3rd-party/SDL2/src/libm/e_log10.c b/source/3rd-party/SDL2/src/libm/e_log10.c
new file mode 100644
index 0000000..a30ba54
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/e_log10.c
@@ -0,0 +1,106 @@
+/*
+ * ====================================================
+ * 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(_MSC_VER) /* Handle Microsoft VC++ compiler specifics. */
+/* C4723: potential divide by zero. */
+#pragma warning ( disable : 4723 )
+#endif
+
+/* __ieee754_log10(x)
+ * Return the base 10 logarithm of x
+ *
+ * Method :
+ * Let log10_2hi = leading 40 bits of log10(2) and
+ * log10_2lo = log10(2) - log10_2hi,
+ * ivln10 = 1/log(10) rounded.
+ * Then
+ * n = ilogb(x),
+ * if(n<0) n = n+1;
+ * x = scalbn(x,-n);
+ * log10(x) := n*log10_2hi + (n*log10_2lo + ivln10*log(x))
+ *
+ * Note 1:
+ * To guarantee log10(10**n)=n, where 10**n is normal, the rounding
+ * mode must set to Round-to-Nearest.
+ * Note 2:
+ * [1/log(10)] rounded to 53 bits has error .198 ulps;
+ * log10 is monotonic at all binary break points.
+ *
+ * Special cases:
+ * log10(x) is NaN with signal if x < 0;
+ * log10(+INF) is +INF with no signal; log10(0) is -INF with signal;
+ * log10(NaN) is that NaN with no signal;
+ * log10(10**N) = N for N=0,1,...,22.
+ *
+ * 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"
+
+static const double
+two54 = 1.80143985094819840000e+16, /* 0x43500000, 0x00000000 */
+ivln10 = 4.34294481903251816668e-01, /* 0x3FDBCB7B, 0x1526E50E */
+log10_2hi = 3.01029995663611771306e-01, /* 0x3FD34413, 0x509F6000 */
+log10_2lo = 3.69423907715893078616e-13; /* 0x3D59FEF3, 0x11F12B36 */
+
+static const double zero = 0.0;
+
+double attribute_hidden __ieee754_log10(double x)
+{
+ double y,z;
+ int32_t i,k,hx;
+ 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;
+ i = ((u_int32_t)k&0x80000000)>>31;
+ hx = (hx&0x000fffff)|((0x3ff-i)<<20);
+ y = (double)(k+i);
+ SET_HIGH_WORD(x,hx);
+ z = y*log10_2lo + ivln10*__ieee754_log(x);
+ return z+y*log10_2hi;
+}
+
+/*
+ * wrapper log10(X)
+ */
+#ifndef _IEEE_LIBM
+double log10(double x)
+{
+ double z = __ieee754_log10(x);
+ if (_LIB_VERSION == _IEEE_ || isnan(x))
+ return z;
+ if (x <= 0.0) {
+ if(x == 0.0)
+ return __kernel_standard(x, x, 18); /* log10(0) */
+ return __kernel_standard(x, x, 19); /* log10(x<0) */
+ }
+ return z;
+}
+#else
+strong_alias(__ieee754_log10, log10)
+#endif
+libm_hidden_def(log10)
diff --git a/source/3rd-party/SDL2/src/libm/e_pow.c b/source/3rd-party/SDL2/src/libm/e_pow.c
new file mode 100644
index 0000000..cfd1dbf
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/e_pow.c
@@ -0,0 +1,343 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* __ieee754_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. +-1 ** anything is 1.0
+ * 2. +-1 ** +-INF is 1.0
+ * 3. (anything) ** 0 is 1
+ * 4. (anything) ** 1 is itself
+ * 5. (anything) ** NAN is NAN
+ * 6. NAN ** (anything except 0) is NAN
+ * 7. +-(|x| > 1) ** +INF is +INF
+ * 8. +-(|x| > 1) ** -INF is +0
+ * 9. +-(|x| < 1) ** +INF is +0
+ * 10 +-(|x| < 1) ** -INF is +INF
+ * 11. +0 ** (+anything except 0, NAN) is +0
+ * 12. -0 ** (+anything except 0, NAN, odd integer) is +0
+ * 13. +0 ** (-anything except 0, NAN) is +INF
+ * 14. -0 ** (-anything except 0, NAN, odd integer) is +INF
+ * 15. -0 ** (odd integer) = -( +0 ** (odd integer) )
+ * 16. +INF ** (+anything except 0,NAN) is +INF
+ * 17. +INF ** (-anything except 0,NAN) is +0
+ * 18. -INF ** (anything) = -0 ** (-anything)
+ * 19. (-anything) ** (integer) is (-1)**(integer)*(+anything**integer)
+ * 20. (-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 "math_libm.h"
+#include "math_private.h"
+
+#if defined(_MSC_VER) /* Handle Microsoft VC++ compiler specifics. */
+/* C4756: overflow in constant arithmetic */
+#pragma warning ( disable : 4756 )
+#endif
+
+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 */
+zero = 0.0,
+one = 1.0,
+two = 2.0,
+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-0017, /* -(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 attribute_hidden __ieee754_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;
+ u_int32_t lx,ly;
+
+ EXTRACT_WORDS(hx,lx,x);
+ /* x==1: 1**y = 1 (even if y is NaN) */
+ if (hx==0x3ff00000 && lx==0) {
+ return x;
+ }
+ ix = hx&0x7fffffff;
+
+ EXTRACT_WORDS(hy,ly,y);
+ iy = hy&0x7fffffff;
+
+ /* y==zero: x**0 = 1 */
+ if((iy|ly)==0) return one;
+
+ /* +-NaN return x+y */
+ 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) {
+ j = ly>>(52-k);
+ if((j<<(52-k))==ly) yisint = 2-(j&1);
+ } else if(ly==0) {
+ 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)
+ return one; /* +-1**+-inf is 1 (yes, weird rule) */
+ if (ix >= 0x3ff00000) /* (|x|>1)**+-inf = inf,0 */
+ return (hy>=0) ? y : zero;
+ /* (|x|<1)**-,+inf = inf,0 */
+ return (hy<0) ? -y : zero;
+ }
+ if(iy==0x3ff00000) { /* y is +-1 */
+ if(hy<0) return one/x; else return x;
+ }
+ if(hy==0x40000000) return x*x; /* y is 2 */
+ if(hy==0x3fe00000) { /* y is 0.5 */
+ if(hx>=0) /* x >= +0 */
+ return __ieee754_sqrt(x);
+ }
+ }
+
+ ax = fabs(x);
+ /* special value of x */
+ if(lx==0) {
+ if(ix==0x7ff00000||ix==0||ix==0x3ff00000){
+ z = ax; /*x is +-0,+-inf,+-1*/
+ if(hy<0) z = one/z; /* z = (1/|x|) */
+ 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;
+ }
+ }
+
+ /* (x<0)**(non-int) is NaN */
+ if(((((u_int32_t)hx>>31)-1)|yisint)==0) return (x-x)/(x-x);
+
+ /* |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)? huge*huge:tiny*tiny;
+ if(ix>0x3ff00000) return (hy>0)? huge*huge: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 = x-1; /* 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 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) k=0; /* |x|<sqrt(3/2) */
+ else if(j<0xBB67A) k=1; /* |x|<sqrt(3) */
+ else {k=0;n+=1;ix -= 0x00100000;}
+ SET_HIGH_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;
+ SET_LOW_WORD(s_h,0);
+ /* t_h=ax+bp[k] High */
+ t_h = zero;
+ 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 = 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 = 3.0+s2+r;
+ SET_LOW_WORD(t_h,0);
+ t_l = r-((t_h-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;
+ 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) = (s+..)*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);
+ }
+
+ s = one; /* s (sign of result -ve**odd) = -1 else = 1 */
+ if(((((u_int32_t)hx>>31)-1)|(yisint-1))==0)
+ s = -one;/* (-ve)**(odd int) */
+
+ /* 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 */
+ else {
+ if(p_l+ovt>z-p_h) return s*huge*huge; /* overflow */
+ }
+ } else if((j&0x7fffffff)>=0x4090cc00 ) { /* z <= -1075 */
+ if(((j-0xc090cc00)|i)!=0) /* z < -1075 */
+ return s*tiny*tiny; /* underflow */
+ else {
+ 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 = zero;
+ 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-two)-(w+z*w);
+ z = one-(r-z);
+ GET_HIGH_WORD(j,z);
+ j += (n<<20);
+ if((j>>20)<=0) z = scalbn(z,n); /* subnormal output */
+ else SET_HIGH_WORD(z,j);
+ return s*z;
+}
+
+/*
+ * wrapper pow(x,y) return x**y
+ */
+#ifndef _IEEE_LIBM
+double pow(double x, double y)
+{
+ double z = __ieee754_pow(x, y);
+ if (_LIB_VERSION == _IEEE_|| isnan(y))
+ return z;
+ if (isnan(x)) {
+ if (y == 0.0)
+ return __kernel_standard(x, y, 42); /* pow(NaN,0.0) */
+ return z;
+ }
+ if (x == 0.0) {
+ if (y == 0.0)
+ return __kernel_standard(x, y, 20); /* pow(0.0,0.0) */
+ if (isfinite(y) && y < 0.0)
+ return __kernel_standard(x,y,23); /* pow(0.0,negative) */
+ return z;
+ }
+ if (!isfinite(z)) {
+ if (isfinite(x) && isfinite(y)) {
+ if (isnan(z))
+ return __kernel_standard(x, y, 24); /* pow neg**non-int */
+ return __kernel_standard(x, y, 21); /* pow overflow */
+ }
+ }
+ if (z == 0.0 && isfinite(x) && isfinite(y))
+ return __kernel_standard(x, y, 22); /* pow underflow */
+ return z;
+}
+#else
+strong_alias(__ieee754_pow, pow)
+#endif
+libm_hidden_def(pow)
diff --git a/source/3rd-party/SDL2/src/libm/e_rem_pio2.c b/source/3rd-party/SDL2/src/libm/e_rem_pio2.c
new file mode 100644
index 0000000..5e055d6
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/e_rem_pio2.c
@@ -0,0 +1,161 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* __ieee754_rem_pio2(x,y)
+ *
+ * return the remainder of x rem pi/2 in y[0]+y[1]
+ * use __kernel_rem_pio2()
+ */
+
+#include "math_libm.h"
+#include "math_private.h"
+
+/*
+ * Table of constants for 2/pi, 396 Hex digits (476 decimal) of 2/pi
+ */
+static const int32_t two_over_pi[] = {
+0xA2F983, 0x6E4E44, 0x1529FC, 0x2757D1, 0xF534DD, 0xC0DB62,
+0x95993C, 0x439041, 0xFE5163, 0xABDEBB, 0xC561B7, 0x246E3A,
+0x424DD2, 0xE00649, 0x2EEA09, 0xD1921C, 0xFE1DEB, 0x1CB129,
+0xA73EE8, 0x8235F5, 0x2EBB44, 0x84E99C, 0x7026B4, 0x5F7E41,
+0x3991D6, 0x398353, 0x39F49C, 0x845F8B, 0xBDF928, 0x3B1FF8,
+0x97FFDE, 0x05980F, 0xEF2F11, 0x8B5A0A, 0x6D1F6D, 0x367ECF,
+0x27CB09, 0xB74F46, 0x3F669E, 0x5FEA2D, 0x7527BA, 0xC7EBE5,
+0xF17B3D, 0x0739F7, 0x8A5292, 0xEA6BFB, 0x5FB11F, 0x8D5D08,
+0x560330, 0x46FC7B, 0x6BABF0, 0xCFBC20, 0x9AF436, 0x1DA9E3,
+0x91615E, 0xE61B08, 0x659985, 0x5F14A0, 0x68408D, 0xFFD880,
+0x4D7327, 0x310606, 0x1556CA, 0x73A8C9, 0x60E27B, 0xC08C6B,
+};
+
+static const int32_t npio2_hw[] = {
+0x3FF921FB, 0x400921FB, 0x4012D97C, 0x401921FB, 0x401F6A7A, 0x4022D97C,
+0x4025FDBB, 0x402921FB, 0x402C463A, 0x402F6A7A, 0x4031475C, 0x4032D97C,
+0x40346B9C, 0x4035FDBB, 0x40378FDB, 0x403921FB, 0x403AB41B, 0x403C463A,
+0x403DD85A, 0x403F6A7A, 0x40407E4C, 0x4041475C, 0x4042106C, 0x4042D97C,
+0x4043A28C, 0x40446B9C, 0x404534AC, 0x4045FDBB, 0x4046C6CB, 0x40478FDB,
+0x404858EB, 0x404921FB,
+};
+
+/*
+ * invpio2: 53 bits of 2/pi
+ * pio2_1: first 33 bit of pi/2
+ * pio2_1t: pi/2 - pio2_1
+ * pio2_2: second 33 bit of pi/2
+ * pio2_2t: pi/2 - (pio2_1+pio2_2)
+ * pio2_3: third 33 bit of pi/2
+ * pio2_3t: pi/2 - (pio2_1+pio2_2+pio2_3)
+ */
+
+static const double
+zero = 0.00000000000000000000e+00, /* 0x00000000, 0x00000000 */
+half = 5.00000000000000000000e-01, /* 0x3FE00000, 0x00000000 */
+two24 = 1.67772160000000000000e+07, /* 0x41700000, 0x00000000 */
+invpio2 = 6.36619772367581382433e-01, /* 0x3FE45F30, 0x6DC9C883 */
+pio2_1 = 1.57079632673412561417e+00, /* 0x3FF921FB, 0x54400000 */
+pio2_1t = 6.07710050650619224932e-11, /* 0x3DD0B461, 0x1A626331 */
+pio2_2 = 6.07710050630396597660e-11, /* 0x3DD0B461, 0x1A600000 */
+pio2_2t = 2.02226624879595063154e-21, /* 0x3BA3198A, 0x2E037073 */
+pio2_3 = 2.02226624871116645580e-21, /* 0x3BA3198A, 0x2E000000 */
+pio2_3t = 8.47842766036889956997e-32; /* 0x397B839A, 0x252049C1 */
+
+int32_t attribute_hidden __ieee754_rem_pio2(double x, double *y)
+{
+ double z=0.0,w,t,r,fn;
+ double tx[3];
+ int32_t e0,i,j,nx,n,ix,hx;
+ u_int32_t low;
+
+ GET_HIGH_WORD(hx,x); /* high word of x */
+ ix = hx&0x7fffffff;
+ if(ix<=0x3fe921fb) /* |x| ~<= pi/4 , no need for reduction */
+ {y[0] = x; y[1] = 0; return 0;}
+ if(ix<0x4002d97c) { /* |x| < 3pi/4, special case with n=+-1 */
+ if(hx>0) {
+ z = x - pio2_1;
+ if(ix!=0x3ff921fb) { /* 33+53 bit pi is good enough */
+ y[0] = z - pio2_1t;
+ y[1] = (z-y[0])-pio2_1t;
+ } else { /* near pi/2, use 33+33+53 bit pi */
+ z -= pio2_2;
+ y[0] = z - pio2_2t;
+ y[1] = (z-y[0])-pio2_2t;
+ }
+ return 1;
+ } else { /* negative x */
+ z = x + pio2_1;
+ if(ix!=0x3ff921fb) { /* 33+53 bit pi is good enough */
+ y[0] = z + pio2_1t;
+ y[1] = (z-y[0])+pio2_1t;
+ } else { /* near pi/2, use 33+33+53 bit pi */
+ z += pio2_2;
+ y[0] = z + pio2_2t;
+ y[1] = (z-y[0])+pio2_2t;
+ }
+ return -1;
+ }
+ }
+ if(ix<=0x413921fb) { /* |x| ~<= 2^19*(pi/2), medium size */
+ t = fabs(x);
+ n = (int32_t) (t*invpio2+half);
+ fn = (double)n;
+ r = t-fn*pio2_1;
+ w = fn*pio2_1t; /* 1st round good to 85 bit */
+ if(n<32&&ix!=npio2_hw[n-1]) {
+ y[0] = r-w; /* quick check no cancellation */
+ } else {
+ u_int32_t high;
+ j = ix>>20;
+ y[0] = r-w;
+ GET_HIGH_WORD(high,y[0]);
+ i = j-((high>>20)&0x7ff);
+ if(i>16) { /* 2nd iteration needed, good to 118 */
+ t = r;
+ w = fn*pio2_2;
+ r = t-w;
+ w = fn*pio2_2t-((t-r)-w);
+ y[0] = r-w;
+ GET_HIGH_WORD(high,y[0]);
+ i = j-((high>>20)&0x7ff);
+ if(i>49) { /* 3rd iteration need, 151 bits acc */
+ t = r; /* will cover all possible cases */
+ w = fn*pio2_3;
+ r = t-w;
+ w = fn*pio2_3t-((t-r)-w);
+ y[0] = r-w;
+ }
+ }
+ }
+ y[1] = (r-y[0])-w;
+ if(hx<0) {y[0] = -y[0]; y[1] = -y[1]; return -n;}
+ else return n;
+ }
+ /*
+ * all other (large) arguments
+ */
+ if(ix>=0x7ff00000) { /* x is inf or NaN */
+ y[0]=y[1]=x-x; return 0;
+ }
+ /* set z = scalbn(|x|,ilogb(x)-23) */
+ GET_LOW_WORD(low,x);
+ SET_LOW_WORD(z,low);
+ e0 = (ix>>20)-1046; /* e0 = ilogb(z)-23; */
+ SET_HIGH_WORD(z, ix - ((int32_t)(e0<<20)));
+ for(i=0;i<2;i++) {
+ tx[i] = (double)((int32_t)(z));
+ z = (z-tx[i])*two24;
+ }
+ tx[2] = z;
+ nx = 3;
+ while((nx > 0) && tx[nx-1]==zero) nx--; /* skip zero term */
+ n = __kernel_rem_pio2(tx,y,e0,nx,2,two_over_pi);
+ if(hx<0) {y[0] = -y[0]; y[1] = -y[1]; return -n;}
+ return n;
+}
diff --git a/source/3rd-party/SDL2/src/libm/e_sqrt.c b/source/3rd-party/SDL2/src/libm/e_sqrt.c
new file mode 100644
index 0000000..39c83e1
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/e_sqrt.c
@@ -0,0 +1,457 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* __ieee754_sqrt(x)
+ * Return correctly rounded sqrt.
+ * ------------------------------------------
+ * | Use the hardware sqrt if you have one |
+ * ------------------------------------------
+ * Method:
+ * Bit by bit method using integer arithmetic. (Slow, but portable)
+ * 1. Normalization
+ * Scale x to y in [1,4) with even powers of 2:
+ * find an integer k such that 1 <= (y=x*2^(2k)) < 4, then
+ * sqrt(x) = 2^k * sqrt(y)
+ * 2. Bit by bit computation
+ * Let q = sqrt(y) truncated to i bit after binary point (q = 1),
+ * i 0
+ * i+1 2
+ * s = 2*q , and y = 2 * ( y - q ). (1)
+ * i i i i
+ *
+ * To compute q from q , one checks whether
+ * i+1 i
+ *
+ * -(i+1) 2
+ * (q + 2 ) <= y. (2)
+ * i
+ * -(i+1)
+ * If (2) is false, then q = q ; otherwise q = q + 2 .
+ * i+1 i i+1 i
+ *
+ * With some algebric manipulation, it is not difficult to see
+ * that (2) is equivalent to
+ * -(i+1)
+ * s + 2 <= y (3)
+ * i i
+ *
+ * The advantage of (3) is that s and y can be computed by
+ * i i
+ * the following recurrence formula:
+ * if (3) is false
+ *
+ * s = s , y = y ; (4)
+ * i+1 i i+1 i
+ *
+ * otherwise,
+ * -i -(i+1)
+ * s = s + 2 , y = y - s - 2 (5)
+ * i+1 i i+1 i i
+ *
+ * One may easily use induction to prove (4) and (5).
+ * Note. Since the left hand side of (3) contain only i+2 bits,
+ * it does not necessary to do a full (53-bit) comparison
+ * in (3).
+ * 3. Final rounding
+ * After generating the 53 bits result, we compute one more bit.
+ * Together with the remainder, we can decide whether the
+ * result is exact, bigger than 1/2ulp, or less than 1/2ulp
+ * (it will never equal to 1/2ulp).
+ * The rounding mode can be detected by checking whether
+ * huge + tiny is equal to huge, and whether huge - tiny is
+ * equal to huge for some floating point number "huge" and "tiny".
+ *
+ * Special cases:
+ * sqrt(+-0) = +-0 ... exact
+ * sqrt(inf) = inf
+ * sqrt(-ve) = NaN ... with invalid signal
+ * sqrt(NaN) = NaN ... with invalid signal for signaling NaN
+ *
+ * Other methods : see the appended file at the end of the program below.
+ *---------------
+ */
+
+#include "math_libm.h"
+#include "math_private.h"
+
+static const double one = 1.0, tiny = 1.0e-300;
+
+double attribute_hidden __ieee754_sqrt(double x)
+{
+ double z;
+ int32_t sign = (int)0x80000000;
+ int32_t ix0,s0,q,m,t,i;
+ u_int32_t r,t1,s1,ix1,q1;
+
+ EXTRACT_WORDS(ix0,ix1,x);
+
+ /* take care of Inf and NaN */
+ if((ix0&0x7ff00000)==0x7ff00000) {
+ return x*x+x; /* sqrt(NaN)=NaN, sqrt(+inf)=+inf
+ sqrt(-inf)=sNaN */
+ }
+ /* take care of zero */
+ if(ix0<=0) {
+ if(((ix0&(~sign))|ix1)==0) return x;/* sqrt(+-0) = +-0 */
+ else if(ix0<0)
+ return (x-x)/(x-x); /* sqrt(-ve) = sNaN */
+ }
+ /* normalize x */
+ m = (ix0>>20);
+ if(m==0) { /* subnormal x */
+ while(ix0==0) {
+ m -= 21;
+ ix0 |= (ix1>>11); ix1 <<= 21;
+ }
+ for(i=0;(ix0&0x00100000)==0;i++) ix0<<=1;
+ m -= i-1;
+ ix0 |= (ix1>>(32-i));
+ ix1 <<= i;
+ }
+ m -= 1023; /* unbias exponent */
+ ix0 = (ix0&0x000fffff)|0x00100000;
+ if(m&1){ /* odd m, double x to make it even */
+ ix0 += ix0 + ((ix1&sign)>>31);
+ ix1 += ix1;
+ }
+ m >>= 1; /* m = [m/2] */
+
+ /* generate sqrt(x) bit by bit */
+ ix0 += ix0 + ((ix1&sign)>>31);
+ ix1 += ix1;
+ q = q1 = s0 = s1 = 0; /* [q,q1] = sqrt(x) */
+ r = 0x00200000; /* r = moving bit from right to left */
+
+ while(r!=0) {
+ t = s0+r;
+ if(t<=ix0) {
+ s0 = t+r;
+ ix0 -= t;
+ q += r;
+ }
+ ix0 += ix0 + ((ix1&sign)>>31);
+ ix1 += ix1;
+ r>>=1;
+ }
+
+ r = sign;
+ while(r!=0) {
+ t1 = s1+r;
+ t = s0;
+ if((t<ix0)||((t==ix0)&&(t1<=ix1))) {
+ s1 = t1+r;
+ if(((t1&sign)==sign)&&(s1&sign)==0) s0 += 1;
+ ix0 -= t;
+ if (ix1 < t1) ix0 -= 1;
+ ix1 -= t1;
+ q1 += r;
+ }
+ ix0 += ix0 + ((ix1&sign)>>31);
+ ix1 += ix1;
+ r>>=1;
+ }
+
+ /* use floating add to find out rounding direction */
+ if((ix0|ix1)!=0) {
+ z = one-tiny; /* trigger inexact flag */
+ if (z>=one) {
+ z = one+tiny;
+ if (q1==(u_int32_t)0xffffffff) { q1=0; q += 1;}
+ else if (z>one) {
+ if (q1==(u_int32_t)0xfffffffe) q+=1;
+ q1+=2;
+ } else
+ q1 += (q1&1);
+ }
+ }
+ ix0 = (q>>1)+0x3fe00000;
+ ix1 = q1>>1;
+ if ((q&1)==1) ix1 |= sign;
+ ix0 += (m <<20);
+ INSERT_WORDS(z,ix0,ix1);
+ return z;
+}
+
+/*
+ * wrapper sqrt(x)
+ */
+#ifndef _IEEE_LIBM
+double sqrt(double x)
+{
+ double z = __ieee754_sqrt(x);
+ if (_LIB_VERSION == _IEEE_ || isnan(x))
+ return z;
+ if (x < 0.0)
+ return __kernel_standard(x, x, 26); /* sqrt(negative) */
+ return z;
+}
+#else
+strong_alias(__ieee754_sqrt, sqrt)
+#endif
+libm_hidden_def(sqrt)
+
+
+/*
+Other methods (use floating-point arithmetic)
+-------------
+(This is a copy of a drafted paper by Prof W. Kahan
+and K.C. Ng, written in May, 1986)
+
+ Two algorithms are given here to implement sqrt(x)
+ (IEEE double precision arithmetic) in software.
+ Both supply sqrt(x) correctly rounded. The first algorithm (in
+ Section A) uses newton iterations and involves four divisions.
+ The second one uses reciproot iterations to avoid division, but
+ requires more multiplications. Both algorithms need the ability
+ to chop results of arithmetic operations instead of round them,
+ and the INEXACT flag to indicate when an arithmetic operation
+ is executed exactly with no roundoff error, all part of the
+ standard (IEEE 754-1985). The ability to perform shift, add,
+ subtract and logical AND operations upon 32-bit words is needed
+ too, though not part of the standard.
+
+A. sqrt(x) by Newton Iteration
+
+ (1) Initial approximation
+
+ Let x0 and x1 be the leading and the trailing 32-bit words of
+ a floating point number x (in IEEE double format) respectively
+
+ 1 11 52 ...widths
+ ------------------------------------------------------
+ x: |s| e | f |
+ ------------------------------------------------------
+ msb lsb msb lsb ...order
+
+
+ ------------------------ ------------------------
+ x0: |s| e | f1 | x1: | f2 |
+ ------------------------ ------------------------
+
+ By performing shifts and subtracts on x0 and x1 (both regarded
+ as integers), we obtain an 8-bit approximation of sqrt(x) as
+ follows.
+
+ k := (x0>>1) + 0x1ff80000;
+ y0 := k - T1[31&(k>>15)]. ... y ~ sqrt(x) to 8 bits
+ Here k is a 32-bit integer and T1[] is an integer array containing
+ correction terms. Now magically the floating value of y (y's
+ leading 32-bit word is y0, the value of its trailing word is 0)
+ approximates sqrt(x) to almost 8-bit.
+
+ Value of T1:
+ static int T1[32]= {
+ 0, 1024, 3062, 5746, 9193, 13348, 18162, 23592,
+ 29598, 36145, 43202, 50740, 58733, 67158, 75992, 85215,
+ 83599, 71378, 60428, 50647, 41945, 34246, 27478, 21581,
+ 16499, 12183, 8588, 5674, 3403, 1742, 661, 130,};
+
+ (2) Iterative refinement
+
+ Apply Heron's rule three times to y, we have y approximates
+ sqrt(x) to within 1 ulp (Unit in the Last Place):
+
+ y := (y+x/y)/2 ... almost 17 sig. bits
+ y := (y+x/y)/2 ... almost 35 sig. bits
+ y := y-(y-x/y)/2 ... within 1 ulp
+
+
+ Remark 1.
+ Another way to improve y to within 1 ulp is:
+
+ y := (y+x/y) ... almost 17 sig. bits to 2*sqrt(x)
+ y := y - 0x00100006 ... almost 18 sig. bits to sqrt(x)
+
+ 2
+ (x-y )*y
+ y := y + 2* ---------- ...within 1 ulp
+ 2
+ 3y + x
+
+
+ This formula has one division fewer than the one above; however,
+ it requires more multiplications and additions. Also x must be
+ scaled in advance to avoid spurious overflow in evaluating the
+ expression 3y*y+x. Hence it is not recommended uless division
+ is slow. If division is very slow, then one should use the
+ reciproot algorithm given in section B.
+
+ (3) Final adjustment
+
+ By twiddling y's last bit it is possible to force y to be
+ correctly rounded according to the prevailing rounding mode
+ as follows. Let r and i be copies of the rounding mode and
+ inexact flag before entering the square root program. Also we
+ use the expression y+-ulp for the next representable floating
+ numbers (up and down) of y. Note that y+-ulp = either fixed
+ point y+-1, or multiply y by nextafter(1,+-inf) in chopped
+ mode.
+
+ I := FALSE; ... reset INEXACT flag I
+ R := RZ; ... set rounding mode to round-toward-zero
+ z := x/y; ... chopped quotient, possibly inexact
+ If(not I) then { ... if the quotient is exact
+ if(z=y) {
+ I := i; ... restore inexact flag
+ R := r; ... restore rounded mode
+ return sqrt(x):=y.
+ } else {
+ z := z - ulp; ... special rounding
+ }
+ }
+ i := TRUE; ... sqrt(x) is inexact
+ If (r=RN) then z=z+ulp ... rounded-to-nearest
+ If (r=RP) then { ... round-toward-+inf
+ y = y+ulp; z=z+ulp;
+ }
+ y := y+z; ... chopped sum
+ y0:=y0-0x00100000; ... y := y/2 is correctly rounded.
+ I := i; ... restore inexact flag
+ R := r; ... restore rounded mode
+ return sqrt(x):=y.
+
+ (4) Special cases
+
+ Square root of +inf, +-0, or NaN is itself;
+ Square root of a negative number is NaN with invalid signal.
+
+
+B. sqrt(x) by Reciproot Iteration
+
+ (1) Initial approximation
+
+ Let x0 and x1 be the leading and the trailing 32-bit words of
+ a floating point number x (in IEEE double format) respectively
+ (see section A). By performing shifs and subtracts on x0 and y0,
+ we obtain a 7.8-bit approximation of 1/sqrt(x) as follows.
+
+ k := 0x5fe80000 - (x0>>1);
+ y0:= k - T2[63&(k>>14)]. ... y ~ 1/sqrt(x) to 7.8 bits
+
+ Here k is a 32-bit integer and T2[] is an integer array
+ containing correction terms. Now magically the floating
+ value of y (y's leading 32-bit word is y0, the value of
+ its trailing word y1 is set to zero) approximates 1/sqrt(x)
+ to almost 7.8-bit.
+
+ Value of T2:
+ static int T2[64]= {
+ 0x1500, 0x2ef8, 0x4d67, 0x6b02, 0x87be, 0xa395, 0xbe7a, 0xd866,
+ 0xf14a, 0x1091b,0x11fcd,0x13552,0x14999,0x15c98,0x16e34,0x17e5f,
+ 0x18d03,0x19a01,0x1a545,0x1ae8a,0x1b5c4,0x1bb01,0x1bfde,0x1c28d,
+ 0x1c2de,0x1c0db,0x1ba73,0x1b11c,0x1a4b5,0x1953d,0x18266,0x16be0,
+ 0x1683e,0x179d8,0x18a4d,0x19992,0x1a789,0x1b445,0x1bf61,0x1c989,
+ 0x1d16d,0x1d77b,0x1dddf,0x1e2ad,0x1e5bf,0x1e6e8,0x1e654,0x1e3cd,
+ 0x1df2a,0x1d635,0x1cb16,0x1be2c,0x1ae4e,0x19bde,0x1868e,0x16e2e,
+ 0x1527f,0x1334a,0x11051,0xe951, 0xbe01, 0x8e0d, 0x5924, 0x1edd,};
+
+ (2) Iterative refinement
+
+ Apply Reciproot iteration three times to y and multiply the
+ result by x to get an approximation z that matches sqrt(x)
+ to about 1 ulp. To be exact, we will have
+ -1ulp < sqrt(x)-z<1.0625ulp.
+
+ ... set rounding mode to Round-to-nearest
+ y := y*(1.5-0.5*x*y*y) ... almost 15 sig. bits to 1/sqrt(x)
+ y := y*((1.5-2^-30)+0.5*x*y*y)... about 29 sig. bits to 1/sqrt(x)
+ ... special arrangement for better accuracy
+ z := x*y ... 29 bits to sqrt(x), with z*y<1
+ z := z + 0.5*z*(1-z*y) ... about 1 ulp to sqrt(x)
+
+ Remark 2. The constant 1.5-2^-30 is chosen to bias the error so that
+ (a) the term z*y in the final iteration is always less than 1;
+ (b) the error in the final result is biased upward so that
+ -1 ulp < sqrt(x) - z < 1.0625 ulp
+ instead of |sqrt(x)-z|<1.03125ulp.
+
+ (3) Final adjustment
+
+ By twiddling y's last bit it is possible to force y to be
+ correctly rounded according to the prevailing rounding mode
+ as follows. Let r and i be copies of the rounding mode and
+ inexact flag before entering the square root program. Also we
+ use the expression y+-ulp for the next representable floating
+ numbers (up and down) of y. Note that y+-ulp = either fixed
+ point y+-1, or multiply y by nextafter(1,+-inf) in chopped
+ mode.
+
+ R := RZ; ... set rounding mode to round-toward-zero
+ switch(r) {
+ case RN: ... round-to-nearest
+ if(x<= z*(z-ulp)...chopped) z = z - ulp; else
+ if(x<= z*(z+ulp)...chopped) z = z; else z = z+ulp;
+ break;
+ case RZ:case RM: ... round-to-zero or round-to--inf
+ R:=RP; ... reset rounding mod to round-to-+inf
+ if(x<z*z ... rounded up) z = z - ulp; else
+ if(x>=(z+ulp)*(z+ulp) ...rounded up) z = z+ulp;
+ break;
+ case RP: ... round-to-+inf
+ if(x>(z+ulp)*(z+ulp)...chopped) z = z+2*ulp; else
+ if(x>z*z ...chopped) z = z+ulp;
+ break;
+ }
+
+ Remark 3. The above comparisons can be done in fixed point. For
+ example, to compare x and w=z*z chopped, it suffices to compare
+ x1 and w1 (the trailing parts of x and w), regarding them as
+ two's complement integers.
+
+ ...Is z an exact square root?
+ To determine whether z is an exact square root of x, let z1 be the
+ trailing part of z, and also let x0 and x1 be the leading and
+ trailing parts of x.
+
+ If ((z1&0x03ffffff)!=0) ... not exact if trailing 26 bits of z!=0
+ I := 1; ... Raise Inexact flag: z is not exact
+ else {
+ j := 1 - [(x0>>20)&1] ... j = logb(x) mod 2
+ k := z1 >> 26; ... get z's 25-th and 26-th
+ fraction bits
+ I := i or (k&j) or ((k&(j+j+1))!=(x1&3));
+ }
+ R:= r ... restore rounded mode
+ return sqrt(x):=z.
+
+ If multiplication is cheaper then the foregoing red tape, the
+ Inexact flag can be evaluated by
+
+ I := i;
+ I := (z*z!=x) or I.
+
+ Note that z*z can overwrite I; this value must be sensed if it is
+ True.
+
+ Remark 4. If z*z = x exactly, then bit 25 to bit 0 of z1 must be
+ zero.
+
+ --------------------
+ z1: | f2 |
+ --------------------
+ bit 31 bit 0
+
+ Further more, bit 27 and 26 of z1, bit 0 and 1 of x1, and the odd
+ or even of logb(x) have the following relations:
+
+ -------------------------------------------------
+ bit 27,26 of z1 bit 1,0 of x1 logb(x)
+ -------------------------------------------------
+ 00 00 odd and even
+ 01 01 even
+ 10 10 odd
+ 10 00 even
+ 11 01 even
+ -------------------------------------------------
+
+ (4) Special cases (see (4) of Section A).
+
+ */
diff --git a/source/3rd-party/SDL2/src/libm/k_cos.c b/source/3rd-party/SDL2/src/libm/k_cos.c
new file mode 100644
index 0000000..e1326fa
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/k_cos.c
@@ -0,0 +1,82 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/*
+ * __kernel_cos( x, y )
+ * kernel cos function on [-pi/4, pi/4], pi/4 ~ 0.785398164
+ * Input x is assumed to be bounded by ~pi/4 in magnitude.
+ * Input y is the tail of x.
+ *
+ * Algorithm
+ * 1. Since cos(-x) = cos(x), we need only to consider positive x.
+ * 2. if x < 2^-27 (hx<0x3e400000 0), return 1 with inexact if x!=0.
+ * 3. cos(x) is approximated by a polynomial of degree 14 on
+ * [0,pi/4]
+ * 4 14
+ * cos(x) ~ 1 - x*x/2 + C1*x + ... + C6*x
+ * where the remez error is
+ *
+ * | 2 4 6 8 10 12 14 | -58
+ * |cos(x)-(1-.5*x +C1*x +C2*x +C3*x +C4*x +C5*x +C6*x )| <= 2
+ * | |
+ *
+ * 4 6 8 10 12 14
+ * 4. let r = C1*x +C2*x +C3*x +C4*x +C5*x +C6*x , then
+ * cos(x) = 1 - x*x/2 + r
+ * since cos(x+y) ~ cos(x) - sin(x)*y
+ * ~ cos(x) - x*y,
+ * a correction term is necessary in cos(x) and hence
+ * cos(x+y) = 1 - (x*x/2 - (r - x*y))
+ * For better accuracy when x > 0.3, let qx = |x|/4 with
+ * the last 32 bits mask off, and if x > 0.78125, let qx = 0.28125.
+ * Then
+ * cos(x+y) = (1-qx) - ((x*x/2-qx) - (r-x*y)).
+ * Note that 1-qx and (x*x/2-qx) is EXACT here, and the
+ * magnitude of the latter is at least a quarter of x*x/2,
+ * thus, reducing the rounding error in the subtraction.
+ */
+
+#include "math_libm.h"
+#include "math_private.h"
+
+static const double
+one = 1.00000000000000000000e+00, /* 0x3FF00000, 0x00000000 */
+C1 = 4.16666666666666019037e-02, /* 0x3FA55555, 0x5555554C */
+C2 = -1.38888888888741095749e-03, /* 0xBF56C16C, 0x16C15177 */
+C3 = 2.48015872894767294178e-05, /* 0x3EFA01A0, 0x19CB1590 */
+C4 = -2.75573143513906633035e-07, /* 0xBE927E4F, 0x809C52AD */
+C5 = 2.08757232129817482790e-09, /* 0x3E21EE9E, 0xBDB4B1C4 */
+C6 = -1.13596475577881948265e-11; /* 0xBDA8FAE9, 0xBE8838D4 */
+
+double attribute_hidden __kernel_cos(double x, double y)
+{
+ double a,hz,z,r,qx;
+ int32_t ix;
+ GET_HIGH_WORD(ix,x);
+ ix &= 0x7fffffff; /* ix = |x|'s high word*/
+ if(ix<0x3e400000) { /* if x < 2**27 */
+ if(((int)x)==0) return one; /* generate inexact */
+ }
+ z = x*x;
+ r = z*(C1+z*(C2+z*(C3+z*(C4+z*(C5+z*C6)))));
+ if(ix < 0x3FD33333) /* if |x| < 0.3 */
+ return one - (0.5*z - (z*r - x*y));
+ else {
+ if(ix > 0x3fe90000) { /* x > 0.78125 */
+ qx = 0.28125;
+ } else {
+ INSERT_WORDS(qx,ix-0x00200000,0); /* x/4 */
+ }
+ hz = 0.5*z-qx;
+ a = one-qx;
+ return a - (hz - (z*r-x*y));
+ }
+}
diff --git a/source/3rd-party/SDL2/src/libm/k_rem_pio2.c b/source/3rd-party/SDL2/src/libm/k_rem_pio2.c
new file mode 100644
index 0000000..393db54
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/k_rem_pio2.c
@@ -0,0 +1,317 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/*
+ * __kernel_rem_pio2(x,y,e0,nx,prec,ipio2)
+ * double x[],y[]; int e0,nx,prec; int ipio2[];
+ *
+ * __kernel_rem_pio2 return the last three digits of N with
+ * y = x - N*pi/2
+ * so that |y| < pi/2.
+ *
+ * The method is to compute the integer (mod 8) and fraction parts of
+ * (2/pi)*x without doing the full multiplication. In general we
+ * skip the part of the product that are known to be a huge integer (
+ * more accurately, = 0 mod 8 ). Thus the number of operations are
+ * independent of the exponent of the input.
+ *
+ * (2/pi) is represented by an array of 24-bit integers in ipio2[].
+ *
+ * Input parameters:
+ * x[] The input value (must be positive) is broken into nx
+ * pieces of 24-bit integers in double precision format.
+ * x[i] will be the i-th 24 bit of x. The scaled exponent
+ * of x[0] is given in input parameter e0 (i.e., x[0]*2^e0
+ * match x's up to 24 bits.
+ *
+ * Example of breaking a double positive z into x[0]+x[1]+x[2]:
+ * e0 = ilogb(z)-23
+ * z = scalbn(z,-e0)
+ * for i = 0,1,2
+ * x[i] = floor(z)
+ * z = (z-x[i])*2**24
+ *
+ *
+ * y[] ouput result in an array of double precision numbers.
+ * The dimension of y[] is:
+ * 24-bit precision 1
+ * 53-bit precision 2
+ * 64-bit precision 2
+ * 113-bit precision 3
+ * The actual value is the sum of them. Thus for 113-bit
+ * precison, one may have to do something like:
+ *
+ * long double t,w,r_head, r_tail;
+ * t = (long double)y[2] + (long double)y[1];
+ * w = (long double)y[0];
+ * r_head = t+w;
+ * r_tail = w - (r_head - t);
+ *
+ * e0 The exponent of x[0]
+ *
+ * nx dimension of x[]
+ *
+ * prec an integer indicating the precision:
+ * 0 24 bits (single)
+ * 1 53 bits (double)
+ * 2 64 bits (extended)
+ * 3 113 bits (quad)
+ *
+ * ipio2[]
+ * integer array, contains the (24*i)-th to (24*i+23)-th
+ * bit of 2/pi after binary point. The corresponding
+ * floating value is
+ *
+ * ipio2[i] * 2^(-24(i+1)).
+ *
+ * External function:
+ * double scalbn(), floor();
+ *
+ *
+ * Here is the description of some local variables:
+ *
+ * jk jk+1 is the initial number of terms of ipio2[] needed
+ * in the computation. The recommended value is 2,3,4,
+ * 6 for single, double, extended,and quad.
+ *
+ * jz local integer variable indicating the number of
+ * terms of ipio2[] used.
+ *
+ * jx nx - 1
+ *
+ * jv index for pointing to the suitable ipio2[] for the
+ * computation. In general, we want
+ * ( 2^e0*x[0] * ipio2[jv-1]*2^(-24jv) )/8
+ * is an integer. Thus
+ * e0-3-24*jv >= 0 or (e0-3)/24 >= jv
+ * Hence jv = max(0,(e0-3)/24).
+ *
+ * jp jp+1 is the number of terms in PIo2[] needed, jp = jk.
+ *
+ * q[] double array with integral value, representing the
+ * 24-bits chunk of the product of x and 2/pi.
+ *
+ * q0 the corresponding exponent of q[0]. Note that the
+ * exponent for q[i] would be q0-24*i.
+ *
+ * PIo2[] double precision array, obtained by cutting pi/2
+ * into 24 bits chunks.
+ *
+ * f[] ipio2[] in floating point
+ *
+ * iq[] integer array by breaking up q[] in 24-bits chunk.
+ *
+ * fq[] final product of x*(2/pi) in fq[0],..,fq[jk]
+ *
+ * ih integer. If >0 it indicates q[] is >= 0.5, hence
+ * it also indicates the *sign* of the result.
+ *
+ */
+
+
+/*
+ * 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"
+
+#include "SDL_assert.h"
+
+static const int init_jk[] = {2,3,4,6}; /* initial value for jk */
+
+static const double PIo2[] = {
+ 1.57079625129699707031e+00, /* 0x3FF921FB, 0x40000000 */
+ 7.54978941586159635335e-08, /* 0x3E74442D, 0x00000000 */
+ 5.39030252995776476554e-15, /* 0x3CF84698, 0x80000000 */
+ 3.28200341580791294123e-22, /* 0x3B78CC51, 0x60000000 */
+ 1.27065575308067607349e-29, /* 0x39F01B83, 0x80000000 */
+ 1.22933308981111328932e-36, /* 0x387A2520, 0x40000000 */
+ 2.73370053816464559624e-44, /* 0x36E38222, 0x80000000 */
+ 2.16741683877804819444e-51, /* 0x3569F31D, 0x00000000 */
+};
+
+static const double
+zero = 0.0,
+one = 1.0,
+two24 = 1.67772160000000000000e+07, /* 0x41700000, 0x00000000 */
+twon24 = 5.96046447753906250000e-08; /* 0x3E700000, 0x00000000 */
+
+int32_t attribute_hidden __kernel_rem_pio2(double *x, double *y, int e0, int nx, const unsigned int prec, const int32_t *ipio2)
+{
+ int32_t jz,jx,jv,jp,jk,carry,n,iq[20],i,j,k,m,q0,ih;
+ double z,fw,f[20],fq[20],q[20];
+
+ if (nx < 1) {
+ return 0;
+ }
+
+ /* initialize jk*/
+ SDL_assert(prec < SDL_arraysize(init_jk));
+ jk = init_jk[prec];
+ SDL_assert(jk > 0);
+ jp = jk;
+
+ /* determine jx,jv,q0, note that 3>q0 */
+ jx = nx-1;
+ jv = (e0-3)/24; if(jv<0) jv=0;
+ q0 = e0-24*(jv+1);
+
+ /* set up f[0] to f[jx+jk] where f[jx+jk] = ipio2[jv+jk] */
+ j = jv-jx; m = jx+jk;
+ for(i=0;i<=m;i++,j++) f[i] = (j<0)? zero : (double) ipio2[j];
+ if ((m+1) < SDL_arraysize(f)) {
+ SDL_memset(&f[m+1], 0, sizeof (f) - ((m+1) * sizeof (f[0])));
+ }
+
+ /* compute q[0],q[1],...q[jk] */
+ for (i=0;i<=jk;i++) {
+ for(j=0,fw=0.0;j<=jx;j++) fw += x[j]*f[jx+i-j];
+ q[i] = fw;
+ }
+
+ jz = jk;
+recompute:
+ /* distill q[] into iq[] reversingly */
+ for(i=0,j=jz,z=q[jz];j>0;i++,j--) {
+ fw = (double)((int32_t)(twon24* z));
+ iq[i] = (int32_t)(z-two24*fw);
+ z = q[j-1]+fw;
+ }
+ if (jz < SDL_arraysize(iq)) {
+ SDL_memset(&iq[jz], 0, sizeof (q) - (jz * sizeof (iq[0])));
+ }
+
+ /* compute n */
+ z = scalbn(z,q0); /* actual value of z */
+ z -= 8.0*floor(z*0.125); /* trim off integer >= 8 */
+ n = (int32_t) z;
+ z -= (double)n;
+ ih = 0;
+ if(q0>0) { /* need iq[jz-1] to determine n */
+ i = (iq[jz-1]>>(24-q0)); n += i;
+ iq[jz-1] -= i<<(24-q0);
+ ih = iq[jz-1]>>(23-q0);
+ }
+ else if(q0==0) ih = iq[jz-1]>>23;
+ else if(z>=0.5) ih=2;
+
+ if(ih>0) { /* q > 0.5 */
+ n += 1; carry = 0;
+ for(i=0;i<jz ;i++) { /* compute 1-q */
+ j = iq[i];
+ if(carry==0) {
+ if(j!=0) {
+ carry = 1; iq[i] = 0x1000000- j;
+ }
+ } else iq[i] = 0xffffff - j;
+ }
+ if(q0>0) { /* rare case: chance is 1 in 12 */
+ switch(q0) {
+ case 1:
+ iq[jz-1] &= 0x7fffff; break;
+ case 2:
+ iq[jz-1] &= 0x3fffff; break;
+ }
+ }
+ if(ih==2) {
+ z = one - z;
+ if(carry!=0) z -= scalbn(one,q0);
+ }
+ }
+
+ /* check if recomputation is needed */
+ if(z==zero) {
+ j = 0;
+ for (i=jz-1;i>=jk;i--) j |= iq[i];
+ if(j==0) { /* need recomputation */
+ for(k=1;iq[jk-k]==0;k++); /* k = no. of terms needed */
+
+ for(i=jz+1;i<=jz+k;i++) { /* add q[jz+1] to q[jz+k] */
+ f[jx+i] = (double) ipio2[jv+i];
+ for(j=0,fw=0.0;j<=jx;j++) fw += x[j]*f[jx+i-j];
+ q[i] = fw;
+ }
+ jz += k;
+ goto recompute;
+ }
+ }
+
+ /* chop off zero terms */
+ if(z==0.0) {
+ jz -= 1; q0 -= 24;
+ SDL_assert(jz >= 0);
+ while(iq[jz]==0) { jz--; SDL_assert(jz >= 0); q0-=24;}
+ } else { /* break z into 24-bit if necessary */
+ z = scalbn(z,-q0);
+ if(z>=two24) {
+ fw = (double)((int32_t)(twon24*z));
+ iq[jz] = (int32_t)(z-two24*fw);
+ jz += 1; q0 += 24;
+ iq[jz] = (int32_t) fw;
+ } else iq[jz] = (int32_t) z ;
+ }
+
+ /* convert integer "bit" chunk to floating-point value */
+ fw = scalbn(one,q0);
+ for(i=jz;i>=0;i--) {
+ q[i] = fw*(double)iq[i]; fw*=twon24;
+ }
+
+ /* compute PIo2[0,...,jp]*q[jz,...,0] */
+ for(i=jz;i>=0;i--) {
+ for(fw=0.0,k=0;k<=jp&&k<=jz-i;k++) fw += PIo2[k]*q[i+k];
+ fq[jz-i] = fw;
+ }
+ if ((jz+1) < SDL_arraysize(f)) {
+ SDL_memset(&fq[jz+1], 0, sizeof (fq) - ((jz+1) * sizeof (fq[0])));
+ }
+
+ /* compress fq[] into y[] */
+ switch(prec) {
+ case 0:
+ fw = 0.0;
+ for (i=jz;i>=0;i--) fw += fq[i];
+ y[0] = (ih==0)? fw: -fw;
+ break;
+ case 1:
+ case 2:
+ fw = 0.0;
+ for (i=jz;i>=0;i--) fw += fq[i];
+ y[0] = (ih==0)? fw: -fw;
+ fw = fq[0]-fw;
+ for (i=1;i<=jz;i++) fw += fq[i];
+ y[1] = (ih==0)? fw: -fw;
+ break;
+ case 3: /* painful */
+ for (i=jz;i>0;i--) {
+ fw = fq[i-1]+fq[i];
+ fq[i] += fq[i-1]-fw;
+ fq[i-1] = fw;
+ }
+ for (i=jz;i>1;i--) {
+ fw = fq[i-1]+fq[i];
+ fq[i] += fq[i-1]-fw;
+ fq[i-1] = fw;
+ }
+ for (fw=0.0,i=jz;i>=2;i--) fw += fq[i];
+ if(ih==0) {
+ y[0] = fq[0]; y[1] = fq[1]; y[2] = fw;
+ } else {
+ y[0] = -fq[0]; y[1] = -fq[1]; y[2] = -fw;
+ }
+ }
+ return n&7;
+}
diff --git a/source/3rd-party/SDL2/src/libm/k_sin.c b/source/3rd-party/SDL2/src/libm/k_sin.c
new file mode 100644
index 0000000..3520d6b
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/k_sin.c
@@ -0,0 +1,65 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* __kernel_sin( x, y, iy)
+ * kernel sin function on [-pi/4, pi/4], pi/4 ~ 0.7854
+ * Input x is assumed to be bounded by ~pi/4 in magnitude.
+ * Input y is the tail of x.
+ * Input iy indicates whether y is 0. (if iy=0, y assume to be 0).
+ *
+ * Algorithm
+ * 1. Since sin(-x) = -sin(x), we need only to consider positive x.
+ * 2. if x < 2^-27 (hx<0x3e400000 0), return x with inexact if x!=0.
+ * 3. sin(x) is approximated by a polynomial of degree 13 on
+ * [0,pi/4]
+ * 3 13
+ * sin(x) ~ x + S1*x + ... + S6*x
+ * where
+ *
+ * |sin(x) 2 4 6 8 10 12 | -58
+ * |----- - (1+S1*x +S2*x +S3*x +S4*x +S5*x +S6*x )| <= 2
+ * | x |
+ *
+ * 4. sin(x+y) = sin(x) + sin'(x')*y
+ * ~ sin(x) + (1-x*x/2)*y
+ * For better accuracy, let
+ * 3 2 2 2 2
+ * r = x *(S2+x *(S3+x *(S4+x *(S5+x *S6))))
+ * then 3 2
+ * sin(x) = x + (S1*x + (x *(r-y/2)+y))
+ */
+
+#include "math_libm.h"
+#include "math_private.h"
+
+static const double
+half = 5.00000000000000000000e-01, /* 0x3FE00000, 0x00000000 */
+S1 = -1.66666666666666324348e-01, /* 0xBFC55555, 0x55555549 */
+S2 = 8.33333333332248946124e-03, /* 0x3F811111, 0x1110F8A6 */
+S3 = -1.98412698298579493134e-04, /* 0xBF2A01A0, 0x19C161D5 */
+S4 = 2.75573137070700676789e-06, /* 0x3EC71DE3, 0x57B1FE7D */
+S5 = -2.50507602534068634195e-08, /* 0xBE5AE5E6, 0x8A2B9CEB */
+S6 = 1.58969099521155010221e-10; /* 0x3DE5D93A, 0x5ACFD57C */
+
+double attribute_hidden __kernel_sin(double x, double y, int iy)
+{
+ double z,r,v;
+ int32_t ix;
+ GET_HIGH_WORD(ix,x);
+ ix &= 0x7fffffff; /* high word of x */
+ if(ix<0x3e400000) /* |x| < 2**-27 */
+ {if((int)x==0) return x;} /* generate inexact */
+ z = x*x;
+ v = z*x;
+ r = S2+z*(S3+z*(S4+z*(S5+z*S6)));
+ if(iy==0) return x+v*(S1+z*r);
+ else return x-((z*(half*y-v*r)-y)-v*S1);
+}
diff --git a/source/3rd-party/SDL2/src/libm/k_tan.c b/source/3rd-party/SDL2/src/libm/k_tan.c
new file mode 100644
index 0000000..47b4e3d
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/k_tan.c
@@ -0,0 +1,118 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* __kernel_tan( x, y, k )
+ * kernel tan function on [-pi/4, pi/4], pi/4 ~ 0.7854
+ * Input x is assumed to be bounded by ~pi/4 in magnitude.
+ * Input y is the tail of x.
+ * Input k indicates whether tan (if k=1) or
+ * -1/tan (if k= -1) is returned.
+ *
+ * Algorithm
+ * 1. Since tan(-x) = -tan(x), we need only to consider positive x.
+ * 2. if x < 2^-28 (hx<0x3e300000 0), return x with inexact if x!=0.
+ * 3. tan(x) is approximated by a odd polynomial of degree 27 on
+ * [0,0.67434]
+ * 3 27
+ * tan(x) ~ x + T1*x + ... + T13*x
+ * where
+ *
+ * |tan(x) 2 4 26 | -59.2
+ * |----- - (1+T1*x +T2*x +.... +T13*x )| <= 2
+ * | x |
+ *
+ * Note: tan(x+y) = tan(x) + tan'(x)*y
+ * ~ tan(x) + (1+x*x)*y
+ * Therefore, for better accuracy in computing tan(x+y), let
+ * 3 2 2 2 2
+ * r = x *(T2+x *(T3+x *(...+x *(T12+x *T13))))
+ * then
+ * 3 2
+ * tan(x+y) = x + (T1*x + (x *(r+y)+y))
+ *
+ * 4. For x in [0.67434,pi/4], let y = pi/4 - x, then
+ * tan(x) = tan(pi/4-y) = (1-tan(y))/(1+tan(y))
+ * = 1 - 2*(tan(y) - (tan(y)^2)/(1+tan(y)))
+ */
+
+#include "math_libm.h"
+#include "math_private.h"
+
+static const double
+one = 1.00000000000000000000e+00, /* 0x3FF00000, 0x00000000 */
+pio4 = 7.85398163397448278999e-01, /* 0x3FE921FB, 0x54442D18 */
+pio4lo= 3.06161699786838301793e-17, /* 0x3C81A626, 0x33145C07 */
+T[] = {
+ 3.33333333333334091986e-01, /* 0x3FD55555, 0x55555563 */
+ 1.33333333333201242699e-01, /* 0x3FC11111, 0x1110FE7A */
+ 5.39682539762260521377e-02, /* 0x3FABA1BA, 0x1BB341FE */
+ 2.18694882948595424599e-02, /* 0x3F9664F4, 0x8406D637 */
+ 8.86323982359930005737e-03, /* 0x3F8226E3, 0xE96E8493 */
+ 3.59207910759131235356e-03, /* 0x3F6D6D22, 0xC9560328 */
+ 1.45620945432529025516e-03, /* 0x3F57DBC8, 0xFEE08315 */
+ 5.88041240820264096874e-04, /* 0x3F4344D8, 0xF2F26501 */
+ 2.46463134818469906812e-04, /* 0x3F3026F7, 0x1A8D1068 */
+ 7.81794442939557092300e-05, /* 0x3F147E88, 0xA03792A6 */
+ 7.14072491382608190305e-05, /* 0x3F12B80F, 0x32F0A7E9 */
+ -1.85586374855275456654e-05, /* 0xBEF375CB, 0xDB605373 */
+ 2.59073051863633712884e-05, /* 0x3EFB2A70, 0x74BF7AD4 */
+};
+
+double attribute_hidden __kernel_tan(double x, double y, int iy)
+{
+ double z,r,v,w,s;
+ int32_t ix,hx;
+ GET_HIGH_WORD(hx,x);
+ ix = hx&0x7fffffff; /* high word of |x| */
+ if(ix<0x3e300000) /* x < 2**-28 */
+ {if((int)x==0) { /* generate inexact */
+ u_int32_t low;
+ GET_LOW_WORD(low,x);
+ if(((ix|low)|(iy+1))==0) return one/fabs(x);
+ else return (iy==1)? x: -one/x;
+ }
+ }
+ if(ix>=0x3FE59428) { /* |x|>=0.6744 */
+ if(hx<0) {x = -x; y = -y;}
+ z = pio4-x;
+ w = pio4lo-y;
+ x = z+w; y = 0.0;
+ }
+ z = x*x;
+ w = z*z;
+ /* Break x^5*(T[1]+x^2*T[2]+...) into
+ * x^5(T[1]+x^4*T[3]+...+x^20*T[11]) +
+ * x^5(x^2*(T[2]+x^4*T[4]+...+x^22*[T12]))
+ */
+ r = T[1]+w*(T[3]+w*(T[5]+w*(T[7]+w*(T[9]+w*T[11]))));
+ v = z*(T[2]+w*(T[4]+w*(T[6]+w*(T[8]+w*(T[10]+w*T[12])))));
+ s = z*x;
+ r = y + z*(s*(r+v)+y);
+ r += T[0]*s;
+ w = x+r;
+ if(ix>=0x3FE59428) {
+ v = (double)iy;
+ return (double)(1-((hx>>30)&2))*(v-2.0*(x-(w*w/(w+v)-r)));
+ }
+ if(iy==1) return w;
+ else { /* if allow error up to 2 ulp,
+ simply return -1.0/(x+r) here */
+ /* compute -1.0/(x+r) accurately */
+ double a,t;
+ z = w;
+ SET_LOW_WORD(z,0);
+ v = r-(z - x); /* z+v = r+x */
+ t = a = -1.0/w; /* a = -1.0/w */
+ SET_LOW_WORD(t,0);
+ s = 1.0+t*z;
+ return t+a*(s+t*v);
+ }
+}
diff --git a/source/3rd-party/SDL2/src/libm/math_libm.h b/source/3rd-party/SDL2/src/libm/math_libm.h
new file mode 100644
index 0000000..3c751c5
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/math_libm.h
@@ -0,0 +1,47 @@
+/*
+ Simple DirectMedia Layer
+ Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
+
+ This software is provided 'as-is', without any express or implied
+ warranty. In no event will the authors be held liable for any damages
+ arising from the use of this software.
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute it
+ freely, subject to the following restrictions:
+
+ 1. The origin of this software must not be misrepresented; you must not
+ claim that you wrote the original software. If you use this software
+ in a product, an acknowledgment in the product documentation would be
+ appreciated but is not required.
+ 2. Altered source versions must be plainly marked as such, and must not be
+ misrepresented as being the original software.
+ 3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef math_libm_h_
+#define math_libm_h_
+
+#include "../SDL_internal.h"
+
+/* Math routines from uClibc: http://www.uclibc.org */
+
+double SDL_uclibc_atan(double x);
+double SDL_uclibc_atan2(double y, double x);
+double SDL_uclibc_copysign(double x, double y);
+double SDL_uclibc_cos(double x);
+double SDL_uclibc_exp(double x);
+double SDL_uclibc_fabs(double x);
+double SDL_uclibc_floor(double x);
+double SDL_uclibc_fmod(double x, double y);
+double SDL_uclibc_log(double x);
+double SDL_uclibc_log10(double x);
+double SDL_uclibc_pow(double x, double y);
+double SDL_uclibc_scalbn(double x, int n);
+double SDL_uclibc_sin(double x);
+double SDL_uclibc_sqrt(double x);
+double SDL_uclibc_tan(double x);
+
+#endif /* math_libm_h_ */
+
+/* vi: set ts=4 sw=4 expandtab: */
diff --git a/source/3rd-party/SDL2/src/libm/math_private.h b/source/3rd-party/SDL2/src/libm/math_private.h
new file mode 100644
index 0000000..d0ef66a
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/math_private.h
@@ -0,0 +1,227 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/*
+ * from: @(#)fdlibm.h 5.1 93/09/24
+ * $Id: math_private.h,v 1.3 2004/02/09 07:10:38 andersen Exp $
+ */
+
+#ifndef _MATH_PRIVATE_H_
+#define _MATH_PRIVATE_H_
+
+/* #include <endian.h> */
+#include "SDL_endian.h"
+/* #include <sys/types.h> */
+
+#define _IEEE_LIBM
+#define attribute_hidden
+#define libm_hidden_proto(x)
+#define libm_hidden_def(x)
+#define strong_alias(x, y)
+
+#ifndef __HAIKU__ /* already defined in a system header. */
+typedef unsigned int u_int32_t;
+#endif
+
+#define atan SDL_uclibc_atan
+#define __ieee754_atan2 SDL_uclibc_atan2
+#define copysign SDL_uclibc_copysign
+#define cos SDL_uclibc_cos
+#define __ieee754_exp SDL_uclibc_exp
+#define fabs SDL_uclibc_fabs
+#define floor SDL_uclibc_floor
+#define __ieee754_fmod SDL_uclibc_fmod
+#define __ieee754_log SDL_uclibc_log
+#define __ieee754_log10 SDL_uclibc_log10
+#define __ieee754_pow SDL_uclibc_pow
+#define scalbln SDL_uclibc_scalbln
+#define scalbn SDL_uclibc_scalbn
+#define sin SDL_uclibc_sin
+#define __ieee754_sqrt SDL_uclibc_sqrt
+#define tan SDL_uclibc_tan
+
+/* The original fdlibm code used statements like:
+ n0 = ((*(int*)&one)>>29)^1; * index of high word *
+ ix0 = *(n0+(int*)&x); * high word of x *
+ ix1 = *((1-n0)+(int*)&x); * low word of x *
+ to dig two 32 bit words out of the 64 bit IEEE floating point
+ value. That is non-ANSI, and, moreover, the gcc instruction
+ scheduler gets it wrong. We instead use the following macros.
+ Unlike the original code, we determine the endianness at compile
+ time, not at run time; I don't see much benefit to selecting
+ endianness at run time. */
+
+/* A union which permits us to convert between a double and two 32 bit
+ ints. */
+
+/*
+ * Math on arm is special:
+ * For FPA, float words are always big-endian.
+ * For VFP, floats words follow the memory system mode.
+ */
+
+#if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
+
+typedef union
+{
+ double value;
+ struct
+ {
+ u_int32_t msw;
+ u_int32_t lsw;
+ } parts;
+} ieee_double_shape_type;
+
+#else
+
+typedef union
+{
+ double value;
+ struct
+ {
+ u_int32_t lsw;
+ u_int32_t msw;
+ } parts;
+} ieee_double_shape_type;
+
+#endif
+
+/* Get two 32 bit ints from a double. */
+
+#define EXTRACT_WORDS(ix0,ix1,d) \
+do { \
+ ieee_double_shape_type ew_u; \
+ ew_u.value = (d); \
+ (ix0) = ew_u.parts.msw; \
+ (ix1) = ew_u.parts.lsw; \
+} while (0)
+
+/* Get the more significant 32 bit int from a double. */
+
+#define GET_HIGH_WORD(i,d) \
+do { \
+ ieee_double_shape_type gh_u; \
+ gh_u.value = (d); \
+ (i) = gh_u.parts.msw; \
+} while (0)
+
+/* Get the less significant 32 bit int from a double. */
+
+#define GET_LOW_WORD(i,d) \
+do { \
+ ieee_double_shape_type gl_u; \
+ gl_u.value = (d); \
+ (i) = gl_u.parts.lsw; \
+} while (0)
+
+/* Set a double from two 32 bit ints. */
+
+#define INSERT_WORDS(d,ix0,ix1) \
+do { \
+ ieee_double_shape_type iw_u; \
+ iw_u.parts.msw = (ix0); \
+ iw_u.parts.lsw = (ix1); \
+ (d) = iw_u.value; \
+} while (0)
+
+/* Set the more significant 32 bits of a double from an int. */
+
+#define SET_HIGH_WORD(d,v) \
+do { \
+ ieee_double_shape_type sh_u; \
+ sh_u.value = (d); \
+ sh_u.parts.msw = (v); \
+ (d) = sh_u.value; \
+} while (0)
+
+/* Set the less significant 32 bits of a double from an int. */
+
+#define SET_LOW_WORD(d,v) \
+do { \
+ ieee_double_shape_type sl_u; \
+ sl_u.value = (d); \
+ sl_u.parts.lsw = (v); \
+ (d) = sl_u.value; \
+} while (0)
+
+/* A union which permits us to convert between a float and a 32 bit
+ int. */
+
+typedef union
+{
+ float value;
+ u_int32_t word;
+} ieee_float_shape_type;
+
+/* Get a 32 bit int from a float. */
+
+#define GET_FLOAT_WORD(i,d) \
+do { \
+ ieee_float_shape_type gf_u; \
+ gf_u.value = (d); \
+ (i) = gf_u.word; \
+} while (0)
+
+/* Set a float from a 32 bit int. */
+
+#define SET_FLOAT_WORD(d,i) \
+do { \
+ ieee_float_shape_type sf_u; \
+ sf_u.word = (i); \
+ (d) = sf_u.value; \
+} while (0)
+
+/* ieee style elementary functions */
+extern double
+__ieee754_sqrt(double)
+ attribute_hidden;
+ extern double __ieee754_acos(double) attribute_hidden;
+ extern double __ieee754_acosh(double) attribute_hidden;
+ extern double __ieee754_log(double) attribute_hidden;
+ extern double __ieee754_atanh(double) attribute_hidden;
+ extern double __ieee754_asin(double) attribute_hidden;
+ extern double __ieee754_atan2(double, double) attribute_hidden;
+ extern double __ieee754_exp(double) attribute_hidden;
+ extern double __ieee754_cosh(double) attribute_hidden;
+ extern double __ieee754_fmod(double, double) attribute_hidden;
+ extern double __ieee754_pow(double, double) attribute_hidden;
+ extern double __ieee754_lgamma_r(double, int *) attribute_hidden;
+ extern double __ieee754_gamma_r(double, int *) attribute_hidden;
+ extern double __ieee754_lgamma(double) attribute_hidden;
+ extern double __ieee754_gamma(double) attribute_hidden;
+ extern double __ieee754_log10(double) attribute_hidden;
+ extern double __ieee754_sinh(double) attribute_hidden;
+ extern double __ieee754_hypot(double, double) attribute_hidden;
+ extern double __ieee754_j0(double) attribute_hidden;
+ extern double __ieee754_j1(double) attribute_hidden;
+ extern double __ieee754_y0(double) attribute_hidden;
+ extern double __ieee754_y1(double) attribute_hidden;
+ extern double __ieee754_jn(int, double) attribute_hidden;
+ extern double __ieee754_yn(int, double) attribute_hidden;
+ extern double __ieee754_remainder(double, double) attribute_hidden;
+ extern int32_t __ieee754_rem_pio2(double, double *) attribute_hidden;
+#if defined(_SCALB_INT)
+ extern double __ieee754_scalb(double, int) attribute_hidden;
+#else
+ extern double __ieee754_scalb(double, double) attribute_hidden;
+#endif
+
+/* fdlibm kernel function */
+#ifndef _IEEE_LIBM
+ extern double __kernel_standard(double, double, int) attribute_hidden;
+#endif
+ extern double __kernel_sin(double, double, int) attribute_hidden;
+ extern double __kernel_cos(double, double) attribute_hidden;
+ extern double __kernel_tan(double, double, int) attribute_hidden;
+ extern int32_t __kernel_rem_pio2(double *, double *, int, int, const unsigned int,
+ const int32_t *) attribute_hidden;
+
+#endif /* _MATH_PRIVATE_H_ */
diff --git a/source/3rd-party/SDL2/src/libm/s_atan.c b/source/3rd-party/SDL2/src/libm/s_atan.c
new file mode 100644
index 0000000..f664f0e
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/s_atan.c
@@ -0,0 +1,114 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* atan(x)
+ * Method
+ * 1. Reduce x to positive by atan(x) = -atan(-x).
+ * 2. According to the integer k=4t+0.25 chopped, t=x, the argument
+ * is further reduced to one of the following intervals and the
+ * arctangent of t is evaluated by the corresponding formula:
+ *
+ * [0,7/16] atan(x) = t-t^3*(a1+t^2*(a2+...(a10+t^2*a11)...)
+ * [7/16,11/16] atan(x) = atan(1/2) + atan( (t-0.5)/(1+t/2) )
+ * [11/16.19/16] atan(x) = atan( 1 ) + atan( (t-1)/(1+t) )
+ * [19/16,39/16] atan(x) = atan(3/2) + atan( (t-1.5)/(1+1.5t) )
+ * [39/16,INF] atan(x) = atan(INF) + atan( -1/t )
+ *
+ * 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"
+
+static const double atanhi[] = {
+ 4.63647609000806093515e-01, /* atan(0.5)hi 0x3FDDAC67, 0x0561BB4F */
+ 7.85398163397448278999e-01, /* atan(1.0)hi 0x3FE921FB, 0x54442D18 */
+ 9.82793723247329054082e-01, /* atan(1.5)hi 0x3FEF730B, 0xD281F69B */
+ 1.57079632679489655800e+00, /* atan(inf)hi 0x3FF921FB, 0x54442D18 */
+};
+
+static const double atanlo[] = {
+ 2.26987774529616870924e-17, /* atan(0.5)lo 0x3C7A2B7F, 0x222F65E2 */
+ 3.06161699786838301793e-17, /* atan(1.0)lo 0x3C81A626, 0x33145C07 */
+ 1.39033110312309984516e-17, /* atan(1.5)lo 0x3C700788, 0x7AF0CBBD */
+ 6.12323399573676603587e-17, /* atan(inf)lo 0x3C91A626, 0x33145C07 */
+};
+
+static const double aT[] = {
+ 3.33333333333329318027e-01, /* 0x3FD55555, 0x5555550D */
+ -1.99999999998764832476e-01, /* 0xBFC99999, 0x9998EBC4 */
+ 1.42857142725034663711e-01, /* 0x3FC24924, 0x920083FF */
+ -1.11111104054623557880e-01, /* 0xBFBC71C6, 0xFE231671 */
+ 9.09088713343650656196e-02, /* 0x3FB745CD, 0xC54C206E */
+ -7.69187620504482999495e-02, /* 0xBFB3B0F2, 0xAF749A6D */
+ 6.66107313738753120669e-02, /* 0x3FB10D66, 0xA0D03D51 */
+ -5.83357013379057348645e-02, /* 0xBFADDE2D, 0x52DEFD9A */
+ 4.97687799461593236017e-02, /* 0x3FA97B4B, 0x24760DEB */
+ -3.65315727442169155270e-02, /* 0xBFA2B444, 0x2C6A6C2F */
+ 1.62858201153657823623e-02, /* 0x3F90AD3A, 0xE322DA11 */
+};
+
+static const double
+one = 1.0,
+huge = 1.0e300;
+
+double atan(double x)
+{
+ double w,s1,s2,z;
+ int32_t ix,hx,id;
+
+ GET_HIGH_WORD(hx,x);
+ ix = hx&0x7fffffff;
+ if(ix>=0x44100000) { /* if |x| >= 2^66 */
+ u_int32_t low;
+ GET_LOW_WORD(low,x);
+ if(ix>0x7ff00000||
+ (ix==0x7ff00000&&(low!=0)))
+ return x+x; /* NaN */
+ if(hx>0) return atanhi[3]+atanlo[3];
+ else return -atanhi[3]-atanlo[3];
+ } if (ix < 0x3fdc0000) { /* |x| < 0.4375 */
+ if (ix < 0x3e200000) { /* |x| < 2^-29 */
+ if(huge+x>one) return x; /* raise inexact */
+ }
+ id = -1;
+ } else {
+ x = fabs(x);
+ if (ix < 0x3ff30000) { /* |x| < 1.1875 */
+ if (ix < 0x3fe60000) { /* 7/16 <=|x|<11/16 */
+ id = 0; x = (2.0*x-one)/(2.0+x);
+ } else { /* 11/16<=|x|< 19/16 */
+ id = 1; x = (x-one)/(x+one);
+ }
+ } else {
+ if (ix < 0x40038000) { /* |x| < 2.4375 */
+ id = 2; x = (x-1.5)/(one+1.5*x);
+ } else { /* 2.4375 <= |x| < 2^66 */
+ id = 3; x = -1.0/x;
+ }
+ }}
+ /* end of argument reduction */
+ z = x*x;
+ w = z*z;
+ /* break sum from i=0 to 10 aT[i]z**(i+1) into odd and even poly */
+ s1 = z*(aT[0]+w*(aT[2]+w*(aT[4]+w*(aT[6]+w*(aT[8]+w*aT[10])))));
+ s2 = w*(aT[1]+w*(aT[3]+w*(aT[5]+w*(aT[7]+w*aT[9]))));
+ if (id<0) return x - x*(s1+s2);
+ else {
+ z = atanhi[id] - ((x*(s1+s2) - atanlo[id]) - x);
+ return (hx<0)? -z:z;
+ }
+}
+libm_hidden_def(atan)
diff --git a/source/3rd-party/SDL2/src/libm/s_copysign.c b/source/3rd-party/SDL2/src/libm/s_copysign.c
new file mode 100644
index 0000000..a2f275b
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/s_copysign.c
@@ -0,0 +1,29 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/*
+ * copysign(double x, double y)
+ * copysign(x,y) returns a value with the magnitude of x and
+ * with the sign bit of y.
+ */
+
+#include "math_libm.h"
+#include "math_private.h"
+
+double copysign(double x, double y)
+{
+ u_int32_t hx,hy;
+ GET_HIGH_WORD(hx,x);
+ GET_HIGH_WORD(hy,y);
+ SET_HIGH_WORD(x,(hx&0x7fffffff)|(hy&0x80000000));
+ return x;
+}
+libm_hidden_def(copysign)
diff --git a/source/3rd-party/SDL2/src/libm/s_cos.c b/source/3rd-party/SDL2/src/libm/s_cos.c
new file mode 100644
index 0000000..5540260
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/s_cos.c
@@ -0,0 +1,73 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* cos(x)
+ * Return cosine function of x.
+ *
+ * kernel function:
+ * __kernel_sin ... sine function on [-pi/4,pi/4]
+ * __kernel_cos ... cosine function on [-pi/4,pi/4]
+ * __ieee754_rem_pio2 ... argument reduction routine
+ *
+ * Method.
+ * Let S,C and T denote the sin, cos and tan respectively on
+ * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
+ * in [-pi/4 , +pi/4], and let n = k mod 4.
+ * We have
+ *
+ * n sin(x) cos(x) tan(x)
+ * ----------------------------------------------------------
+ * 0 S C T
+ * 1 C -S -1/T
+ * 2 -S -C T
+ * 3 -C S -1/T
+ * ----------------------------------------------------------
+ *
+ * Special cases:
+ * Let trig be any of sin, cos, or tan.
+ * trig(+-INF) is NaN, with signals;
+ * trig(NaN) is that NaN;
+ *
+ * Accuracy:
+ * TRIG(x) returns trig(x) nearly rounded
+ */
+
+#include "math_libm.h"
+#include "math_private.h"
+
+double cos(double x)
+{
+ double y[2],z=0.0;
+ int32_t n, ix;
+
+ /* High word of x. */
+ GET_HIGH_WORD(ix,x);
+
+ /* |x| ~< pi/4 */
+ ix &= 0x7fffffff;
+ if(ix <= 0x3fe921fb) return __kernel_cos(x,z);
+
+ /* cos(Inf or NaN) is NaN */
+ else if (ix>=0x7ff00000) return x-x;
+
+ /* argument reduction needed */
+ else {
+ n = __ieee754_rem_pio2(x,y);
+ switch(n&3) {
+ case 0: return __kernel_cos(y[0],y[1]);
+ case 1: return -__kernel_sin(y[0],y[1],1);
+ case 2: return -__kernel_cos(y[0],y[1]);
+ default:
+ return __kernel_sin(y[0],y[1],1);
+ }
+ }
+}
+libm_hidden_def(cos)
diff --git a/source/3rd-party/SDL2/src/libm/s_fabs.c b/source/3rd-party/SDL2/src/libm/s_fabs.c
new file mode 100644
index 0000000..9ee943c
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/s_fabs.c
@@ -0,0 +1,29 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/*
+ * fabs(x) returns the absolute value of x.
+ */
+
+/*#include <features.h>*/
+/* Prevent math.h from defining a colliding inline */
+#undef __USE_EXTERN_INLINES
+#include "math_libm.h"
+#include "math_private.h"
+
+double fabs(double x)
+{
+ u_int32_t high;
+ GET_HIGH_WORD(high,x);
+ SET_HIGH_WORD(x,high&0x7fffffff);
+ return x;
+}
+libm_hidden_def(fabs)
diff --git a/source/3rd-party/SDL2/src/libm/s_floor.c b/source/3rd-party/SDL2/src/libm/s_floor.c
new file mode 100644
index 0000000..3f9a5ce
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/s_floor.c
@@ -0,0 +1,71 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/*
+ * floor(x)
+ * Return x rounded toward -inf to integral value
+ * Method:
+ * Bit twiddling.
+ * Exception:
+ * Inexact flag raised if x not equal to floor(x).
+ */
+
+/*#include <features.h>*/
+/* Prevent math.h from defining a colliding inline */
+#undef __USE_EXTERN_INLINES
+#include "math_libm.h"
+#include "math_private.h"
+
+static const double huge = 1.0e300;
+
+double floor(double x)
+{
+ int32_t i0,i1,j0;
+ u_int32_t i,j;
+ EXTRACT_WORDS(i0,i1,x);
+ j0 = ((i0>>20)&0x7ff)-0x3ff;
+ if(j0<20) {
+ if(j0<0) { /* raise inexact if x != 0 */
+ if(huge+x>0.0) {/* return 0*sign(x) if |x|<1 */
+ if(i0>=0) {i0=i1=0;}
+ else if(((i0&0x7fffffff)|i1)!=0)
+ { i0=0xbff00000;i1=0;}
+ }
+ } else {
+ i = (0x000fffff)>>j0;
+ if(((i0&i)|i1)==0) return x; /* x is integral */
+ if(huge+x>0.0) { /* raise inexact flag */
+ if(i0<0) i0 += (0x00100000)>>j0;
+ i0 &= (~i); i1=0;
+ }
+ }
+ } else if (j0>51) {
+ if(j0==0x400) return x+x; /* inf or NaN */
+ else return x; /* x is integral */
+ } else {
+ i = ((u_int32_t)(0xffffffff))>>(j0-20);
+ if((i1&i)==0) return x; /* x is integral */
+ if(huge+x>0.0) { /* raise inexact flag */
+ if(i0<0) {
+ if(j0==20) i0+=1;
+ else {
+ j = i1+(1<<(52-j0));
+ if(j<(u_int32_t)i1) i0 +=1 ; /* got a carry */
+ i1=j;
+ }
+ }
+ i1 &= (~i);
+ }
+ }
+ INSERT_WORDS(x,i0,i1);
+ return x;
+}
+libm_hidden_def(floor)
diff --git a/source/3rd-party/SDL2/src/libm/s_scalbn.c b/source/3rd-party/SDL2/src/libm/s_scalbn.c
new file mode 100644
index 0000000..6bb7192
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/s_scalbn.c
@@ -0,0 +1,69 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/*
+ * scalbln(double x, long n)
+ * scalbln(x,n) returns x * 2**n computed by exponent
+ * manipulation rather than by actually performing an
+ * exponentiation or a multiplication.
+ */
+
+#include "math_libm.h"
+#include "math_private.h"
+#include <limits.h>
+
+static const double
+two54 = 1.80143985094819840000e+16, /* 0x43500000, 0x00000000 */
+twom54 = 5.55111512312578270212e-17, /* 0x3C900000, 0x00000000 */
+huge = 1.0e+300,
+tiny = 1.0e-300;
+
+double scalbln(double x, long n)
+{
+ int32_t k, hx, lx;
+
+ EXTRACT_WORDS(hx, lx, x);
+ k = (hx & 0x7ff00000) >> 20; /* extract exponent */
+ if (k == 0) { /* 0 or subnormal x */
+ if ((lx | (hx & 0x7fffffff)) == 0)
+ return x; /* +-0 */
+ x *= two54;
+ GET_HIGH_WORD(hx, x);
+ k = ((hx & 0x7ff00000) >> 20) - 54;
+ }
+ if (k == 0x7ff)
+ return x + x; /* NaN or Inf */
+ k = k + n;
+ if (k > 0x7fe)
+ return huge * copysign(huge, x); /* overflow */
+ if (n < -50000)
+ return tiny * copysign(tiny, x); /* underflow */
+ if (k > 0) { /* normal result */
+ SET_HIGH_WORD(x, (hx & 0x800fffff) | (k << 20));
+ return x;
+ }
+ if (k <= -54) {
+ if (n > 50000) /* in case integer overflow in n+k */
+ return huge * copysign(huge, x); /* overflow */
+ return tiny * copysign(tiny, x); /* underflow */
+ }
+ k += 54; /* subnormal result */
+ SET_HIGH_WORD(x, (hx & 0x800fffff) | (k << 20));
+ return x * twom54;
+}
+libm_hidden_def(scalbln)
+
+
+double scalbn(double x, int n)
+{
+ return scalbln(x, n);
+}
+libm_hidden_def(scalbn)
diff --git a/source/3rd-party/SDL2/src/libm/s_sin.c b/source/3rd-party/SDL2/src/libm/s_sin.c
new file mode 100644
index 0000000..b3cd7a0
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/s_sin.c
@@ -0,0 +1,73 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* sin(x)
+ * Return sine function of x.
+ *
+ * kernel function:
+ * __kernel_sin ... sine function on [-pi/4,pi/4]
+ * __kernel_cos ... cose function on [-pi/4,pi/4]
+ * __ieee754_rem_pio2 ... argument reduction routine
+ *
+ * Method.
+ * Let S,C and T denote the sin, cos and tan respectively on
+ * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
+ * in [-pi/4 , +pi/4], and let n = k mod 4.
+ * We have
+ *
+ * n sin(x) cos(x) tan(x)
+ * ----------------------------------------------------------
+ * 0 S C T
+ * 1 C -S -1/T
+ * 2 -S -C T
+ * 3 -C S -1/T
+ * ----------------------------------------------------------
+ *
+ * Special cases:
+ * Let trig be any of sin, cos, or tan.
+ * trig(+-INF) is NaN, with signals;
+ * trig(NaN) is that NaN;
+ *
+ * Accuracy:
+ * TRIG(x) returns trig(x) nearly rounded
+ */
+
+#include "math_libm.h"
+#include "math_private.h"
+
+double sin(double x)
+{
+ double y[2],z=0.0;
+ int32_t n, ix;
+
+ /* High word of x. */
+ GET_HIGH_WORD(ix,x);
+
+ /* |x| ~< pi/4 */
+ ix &= 0x7fffffff;
+ if(ix <= 0x3fe921fb) return __kernel_sin(x,z,0);
+
+ /* sin(Inf or NaN) is NaN */
+ else if (ix>=0x7ff00000) return x-x;
+
+ /* argument reduction needed */
+ else {
+ n = __ieee754_rem_pio2(x,y);
+ switch(n&3) {
+ case 0: return __kernel_sin(y[0],y[1],1);
+ case 1: return __kernel_cos(y[0],y[1]);
+ case 2: return -__kernel_sin(y[0],y[1],1);
+ default:
+ return -__kernel_cos(y[0],y[1]);
+ }
+ }
+}
+libm_hidden_def(sin)
diff --git a/source/3rd-party/SDL2/src/libm/s_tan.c b/source/3rd-party/SDL2/src/libm/s_tan.c
new file mode 100644
index 0000000..18c8f5b
--- /dev/null
+++ b/source/3rd-party/SDL2/src/libm/s_tan.c
@@ -0,0 +1,67 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* tan(x)
+ * Return tangent function of x.
+ *
+ * kernel function:
+ * __kernel_tan ... tangent function on [-pi/4,pi/4]
+ * __ieee754_rem_pio2 ... argument reduction routine
+ *
+ * Method.
+ * Let S,C and T denote the sin, cos and tan respectively on
+ * [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
+ * in [-pi/4 , +pi/4], and let n = k mod 4.
+ * We have
+ *
+ * n sin(x) cos(x) tan(x)
+ * ----------------------------------------------------------
+ * 0 S C T
+ * 1 C -S -1/T
+ * 2 -S -C T
+ * 3 -C S -1/T
+ * ----------------------------------------------------------
+ *
+ * Special cases:
+ * Let trig be any of sin, cos, or tan.
+ * trig(+-INF) is NaN, with signals;
+ * trig(NaN) is that NaN;
+ *
+ * Accuracy:
+ * TRIG(x) returns trig(x) nearly rounded
+ */
+
+#include "math_libm.h"
+#include "math_private.h"
+
+double tan(double x)
+{
+ double y[2],z=0.0;
+ int32_t n, ix;
+
+ /* High word of x. */
+ GET_HIGH_WORD(ix,x);
+
+ /* |x| ~< pi/4 */
+ ix &= 0x7fffffff;
+ if(ix <= 0x3fe921fb) return __kernel_tan(x,z,1);
+
+ /* tan(Inf or NaN) is NaN */
+ else if (ix>=0x7ff00000) return x-x; /* NaN */
+
+ /* argument reduction needed */
+ else {
+ n = __ieee754_rem_pio2(x,y);
+ return __kernel_tan(y[0],y[1],1-((n&1)<<1)); /* 1 -- n even
+ -1 -- n odd */
+ }
+}
+libm_hidden_def(tan)