msvcrt: Import atan2f from musl.

Signed-off-by: Piotr Caban <piotr@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>
This commit is contained in:
Piotr Caban 2020-08-06 16:59:21 +02:00 committed by Alexandre Julliard
parent 2cb6a1780c
commit 5eaa4c56b1

View file

@ -340,12 +340,73 @@ float CDECL MSVCRT_atanf( float x )
/*********************************************************************
* MSVCRT_atan2f (MSVCRT.@)
*
* Copied from musl: src/math/atan2f.c
*/
float CDECL MSVCRT_atan2f( float x, float y )
float CDECL MSVCRT_atan2f( float y, float x )
{
float ret = atan2f(x, y);
if (isnan(x)) return math_error(_DOMAIN, "atan2f", x, y, ret);
return ret;
static const float pi = 3.1415927410e+00,
pi_lo = -8.7422776573e-08;
float z;
unsigned int m, ix, iy;
if (MSVCRT__isnanf(x) || MSVCRT__isnanf(y))
return x + y;
ix = *(unsigned int*)&x;
iy = *(unsigned int*)&y;
if (ix == 0x3f800000) /* x=1.0 */
return atanf(y);
m = ((iy >> 31) & 1) | ((ix >> 30) & 2); /* 2*sign(x)+sign(y) */
ix &= 0x7fffffff;
iy &= 0x7fffffff;
/* when y = 0 */
if (iy == 0) {
switch (m) {
case 0:
case 1: return y; /* atan(+-0,+anything)=+-0 */
case 2: return pi; /* atan(+0,-anything) = pi */
case 3: return -pi; /* atan(-0,-anything) =-pi */
}
}
/* when x = 0 */
if (ix == 0)
return m & 1 ? -pi / 2 : pi / 2;
/* when x is INF */
if (ix == 0x7f800000) {
if (iy == 0x7f800000) {
switch (m) {
case 0: return pi / 4; /* atan(+INF,+INF) */
case 1: return -pi / 4; /* atan(-INF,+INF) */
case 2: return 3 * pi / 4; /*atan(+INF,-INF)*/
case 3: return -3 * pi / 4; /*atan(-INF,-INF)*/
}
} else {
switch (m) {
case 0: return 0.0f; /* atan(+...,+INF) */
case 1: return -0.0f; /* atan(-...,+INF) */
case 2: return pi; /* atan(+...,-INF) */
case 3: return -pi; /* atan(-...,-INF) */
}
}
}
/* |y/x| > 0x1p26 */
if (ix + (26 << 23) < iy || iy == 0x7f800000)
return m & 1 ? -pi / 2 : pi / 2;
/* z = atan(|y/x|) with correct underflow */
if ((m & 2) && iy + (26 << 23) < ix) /*|y/x| < 0x1p-26, x < 0 */
z = 0.0;
else
z = atanf(fabsf(y / x));
switch (m) {
case 0: return z; /* atan(+,+) */
case 1: return -z; /* atan(-,+) */
case 2: return pi - (z - pi_lo); /* atan(+,-) */
default: /* case 3 */
return (z - pi_lo) - pi; /* atan(-,-) */
}
}
/*********************************************************************