msvcrt: Import atan2 from musl.
Signed-off-by: Piotr Caban <piotr@codeweavers.com> Signed-off-by: Alexandre Julliard <julliard@winehq.org>
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@ -798,12 +798,75 @@ double CDECL MSVCRT_atan( double x )
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/*********************************************************************
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* MSVCRT_atan2 (MSVCRT.@)
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*
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* Copied from musl: src/math/atan2.c
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*/
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double CDECL MSVCRT_atan2( double x, double y )
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double CDECL MSVCRT_atan2( double y, double x )
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{
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double ret = atan2(x, y);
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if (isnan(x)) return math_error(_DOMAIN, "atan2", x, y, ret);
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return ret;
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static const double pi = 3.1415926535897931160E+00,
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pi_lo = 1.2246467991473531772E-16;
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double z;
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unsigned int m, lx, ly, ix, iy;
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if (isnan(x) || isnan(y))
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return x+y;
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ix = *(ULONGLONG*)&x >> 32;
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lx = *(ULONGLONG*)&x;
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iy = *(ULONGLONG*)&y >> 32;
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ly = *(ULONGLONG*)&y;
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if (((ix - 0x3ff00000) | lx) == 0) /* x = 1.0 */
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return atan(y);
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m = ((iy >> 31) & 1) | ((ix >> 30) & 2); /* 2*sign(x)+sign(y) */
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ix = ix & 0x7fffffff;
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iy = iy & 0x7fffffff;
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/* when y = 0 */
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if ((iy | ly) == 0) {
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switch(m) {
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case 0:
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case 1: return y; /* atan(+-0,+anything)=+-0 */
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case 2: return pi; /* atan(+0,-anything) = pi */
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case 3: return -pi; /* atan(-0,-anything) =-pi */
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}
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}
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/* when x = 0 */
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if ((ix | lx) == 0)
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return m & 1 ? -pi / 2 : pi / 2;
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/* when x is INF */
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if (ix == 0x7ff00000) {
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if (iy == 0x7ff00000) {
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switch(m) {
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case 0: return pi / 4; /* atan(+INF,+INF) */
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case 1: return -pi / 4; /* atan(-INF,+INF) */
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case 2: return 3 * pi / 4; /* atan(+INF,-INF) */
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case 3: return -3 * pi / 4; /* atan(-INF,-INF) */
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}
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} else {
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switch(m) {
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case 0: return 0.0; /* atan(+...,+INF) */
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case 1: return -0.0; /* atan(-...,+INF) */
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case 2: return pi; /* atan(+...,-INF) */
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case 3: return -pi; /* atan(-...,-INF) */
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}
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}
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}
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/* |y/x| > 0x1p64 */
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if (ix + (64 << 20) < iy || iy == 0x7ff00000)
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return m & 1 ? -pi / 2 : pi / 2;
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/* z = atan(|y/x|) without spurious underflow */
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if ((m & 2) && iy + (64 << 20) < ix) /* |y/x| < 0x1p-64, x<0 */
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z = 0;
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else
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z = atan(fabs(y / x));
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switch (m) {
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case 0: return z; /* atan(+,+) */
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case 1: return -z; /* atan(-,+) */
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case 2: return pi - (z - pi_lo); /* atan(+,-) */
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default: /* case 3 */
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return (z - pi_lo) - pi; /* atan(-,-) */
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}
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}
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/*********************************************************************
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