Index: fusl/src/math/atan.c |
diff --git a/fusl/src/math/atan.c b/fusl/src/math/atan.c |
index 63b0ab25e3cf02ea81bab5a9ee4d99d6c40bb582..8d33b5364bad6a693b7d7ad07b76b4b2d6b26dec 100644 |
--- a/fusl/src/math/atan.c |
+++ b/fusl/src/math/atan.c |
@@ -29,88 +29,87 @@ |
* to produce the hexadecimal values shown. |
*/ |
- |
#include "libm.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 */ |
+ 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 */ |
+ 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 */ |
+ 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 */ |
}; |
-double atan(double x) |
-{ |
- double_t w,s1,s2,z; |
- uint32_t ix,sign; |
- int id; |
+double atan(double x) { |
+ double_t w, s1, s2, z; |
+ uint32_t ix, sign; |
+ int id; |
- GET_HIGH_WORD(ix, x); |
- sign = ix >> 31; |
- ix &= 0x7fffffff; |
- if (ix >= 0x44100000) { /* if |x| >= 2^66 */ |
- if (isnan(x)) |
- return x; |
- z = atanhi[3] + 0x1p-120f; |
- return sign ? -z : z; |
- } |
- if (ix < 0x3fdc0000) { /* |x| < 0.4375 */ |
- if (ix < 0x3e400000) { /* |x| < 2^-27 */ |
- if (ix < 0x00100000) |
- /* raise underflow for subnormal x */ |
- FORCE_EVAL((float)x); |
- return x; |
- } |
- 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-1.0)/(2.0+x); |
- } else { /* 11/16 <= |x| < 19/16 */ |
- id = 1; |
- x = (x-1.0)/(x+1.0); |
- } |
- } else { |
- if (ix < 0x40038000) { /* |x| < 2.4375 */ |
- id = 2; |
- x = (x-1.5)/(1.0+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); |
- z = atanhi[id] - (x*(s1+s2) - atanlo[id] - x); |
- return sign ? -z : z; |
+ GET_HIGH_WORD(ix, x); |
+ sign = ix >> 31; |
+ ix &= 0x7fffffff; |
+ if (ix >= 0x44100000) { /* if |x| >= 2^66 */ |
+ if (isnan(x)) |
+ return x; |
+ z = atanhi[3] + 0x1p-120f; |
+ return sign ? -z : z; |
+ } |
+ if (ix < 0x3fdc0000) { /* |x| < 0.4375 */ |
+ if (ix < 0x3e400000) { /* |x| < 2^-27 */ |
+ if (ix < 0x00100000) |
+ /* raise underflow for subnormal x */ |
+ FORCE_EVAL((float)x); |
+ return x; |
+ } |
+ 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 - 1.0) / (2.0 + x); |
+ } else { /* 11/16 <= |x| < 19/16 */ |
+ id = 1; |
+ x = (x - 1.0) / (x + 1.0); |
+ } |
+ } else { |
+ if (ix < 0x40038000) { /* |x| < 2.4375 */ |
+ id = 2; |
+ x = (x - 1.5) / (1.0 + 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); |
+ z = atanhi[id] - (x * (s1 + s2) - atanlo[id] - x); |
+ return sign ? -z : z; |
} |