| Index: fusl/src/math/atan2f.c
|
| diff --git a/fusl/src/math/atan2f.c b/fusl/src/math/atan2f.c
|
| index c634d00fc93195f63d25b59c0ae6e4a0e8e826d2..559f0b7579677e73aa5e02df38da359e6f8fc65a 100644
|
| --- a/fusl/src/math/atan2f.c
|
| +++ b/fusl/src/math/atan2f.c
|
| @@ -15,69 +15,81 @@
|
|
|
| #include "libm.h"
|
|
|
| -static const float
|
| -pi = 3.1415927410e+00, /* 0x40490fdb */
|
| -pi_lo = -8.7422776573e-08; /* 0xb3bbbd2e */
|
| +static const float pi = 3.1415927410e+00, /* 0x40490fdb */
|
| + pi_lo = -8.7422776573e-08; /* 0xb3bbbd2e */
|
|
|
| -float atan2f(float y, float x)
|
| -{
|
| - float z;
|
| - uint32_t m,ix,iy;
|
| +float atan2f(float y, float x) {
|
| + float z;
|
| + uint32_t m, ix, iy;
|
|
|
| - if (isnan(x) || isnan(y))
|
| - return x+y;
|
| - GET_FLOAT_WORD(ix, x);
|
| - GET_FLOAT_WORD(iy, 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;
|
| + if (isnan(x) || isnan(y))
|
| + return x + y;
|
| + GET_FLOAT_WORD(ix, x);
|
| + GET_FLOAT_WORD(iy, 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;
|
| + /* 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(-,-) */
|
| - }
|
| + /* 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(-,-) */
|
| + }
|
| }
|
|
|