Index: fusl/src/math/atanf.c |
diff --git a/fusl/src/math/atanf.c b/fusl/src/math/atanf.c |
index 178341b670fa249fa50157d878ac2a66bd7f1843..a63fccc4ab22c286190a271726d3eec51133d195 100644 |
--- a/fusl/src/math/atanf.c |
+++ b/fusl/src/math/atanf.c |
@@ -13,82 +13,77 @@ |
* ==================================================== |
*/ |
- |
#include "libm.h" |
static const float atanhi[] = { |
- 4.6364760399e-01, /* atan(0.5)hi 0x3eed6338 */ |
- 7.8539812565e-01, /* atan(1.0)hi 0x3f490fda */ |
- 9.8279368877e-01, /* atan(1.5)hi 0x3f7b985e */ |
- 1.5707962513e+00, /* atan(inf)hi 0x3fc90fda */ |
+ 4.6364760399e-01, /* atan(0.5)hi 0x3eed6338 */ |
+ 7.8539812565e-01, /* atan(1.0)hi 0x3f490fda */ |
+ 9.8279368877e-01, /* atan(1.5)hi 0x3f7b985e */ |
+ 1.5707962513e+00, /* atan(inf)hi 0x3fc90fda */ |
}; |
static const float atanlo[] = { |
- 5.0121582440e-09, /* atan(0.5)lo 0x31ac3769 */ |
- 3.7748947079e-08, /* atan(1.0)lo 0x33222168 */ |
- 3.4473217170e-08, /* atan(1.5)lo 0x33140fb4 */ |
- 7.5497894159e-08, /* atan(inf)lo 0x33a22168 */ |
+ 5.0121582440e-09, /* atan(0.5)lo 0x31ac3769 */ |
+ 3.7748947079e-08, /* atan(1.0)lo 0x33222168 */ |
+ 3.4473217170e-08, /* atan(1.5)lo 0x33140fb4 */ |
+ 7.5497894159e-08, /* atan(inf)lo 0x33a22168 */ |
}; |
static const float aT[] = { |
- 3.3333328366e-01, |
- -1.9999158382e-01, |
- 1.4253635705e-01, |
- -1.0648017377e-01, |
- 6.1687607318e-02, |
+ 3.3333328366e-01, -1.9999158382e-01, 1.4253635705e-01, |
+ -1.0648017377e-01, 6.1687607318e-02, |
}; |
-float atanf(float x) |
-{ |
- float_t w,s1,s2,z; |
- uint32_t ix,sign; |
- int id; |
+float atanf(float x) { |
+ float_t w, s1, s2, z; |
+ uint32_t ix, sign; |
+ int id; |
- GET_FLOAT_WORD(ix, x); |
- sign = ix>>31; |
- ix &= 0x7fffffff; |
- if (ix >= 0x4c800000) { /* if |x| >= 2**26 */ |
- if (isnan(x)) |
- return x; |
- z = atanhi[3] + 0x1p-120f; |
- return sign ? -z : z; |
- } |
- if (ix < 0x3ee00000) { /* |x| < 0.4375 */ |
- if (ix < 0x39800000) { /* |x| < 2**-12 */ |
- if (ix < 0x00800000) |
- /* raise underflow for subnormal x */ |
- FORCE_EVAL(x*x); |
- return x; |
- } |
- id = -1; |
- } else { |
- x = fabsf(x); |
- if (ix < 0x3f980000) { /* |x| < 1.1875 */ |
- if (ix < 0x3f300000) { /* 7/16 <= |x| < 11/16 */ |
- id = 0; |
- x = (2.0f*x - 1.0f)/(2.0f + x); |
- } else { /* 11/16 <= |x| < 19/16 */ |
- id = 1; |
- x = (x - 1.0f)/(x + 1.0f); |
- } |
- } else { |
- if (ix < 0x401c0000) { /* |x| < 2.4375 */ |
- id = 2; |
- x = (x - 1.5f)/(1.0f + 1.5f*x); |
- } else { /* 2.4375 <= |x| < 2**26 */ |
- id = 3; |
- x = -1.0f/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])); |
- s2 = w*(aT[1]+w*aT[3]); |
- if (id < 0) |
- return x - x*(s1+s2); |
- z = atanhi[id] - ((x*(s1+s2) - atanlo[id]) - x); |
- return sign ? -z : z; |
+ GET_FLOAT_WORD(ix, x); |
+ sign = ix >> 31; |
+ ix &= 0x7fffffff; |
+ if (ix >= 0x4c800000) { /* if |x| >= 2**26 */ |
+ if (isnan(x)) |
+ return x; |
+ z = atanhi[3] + 0x1p-120f; |
+ return sign ? -z : z; |
+ } |
+ if (ix < 0x3ee00000) { /* |x| < 0.4375 */ |
+ if (ix < 0x39800000) { /* |x| < 2**-12 */ |
+ if (ix < 0x00800000) |
+ /* raise underflow for subnormal x */ |
+ FORCE_EVAL(x * x); |
+ return x; |
+ } |
+ id = -1; |
+ } else { |
+ x = fabsf(x); |
+ if (ix < 0x3f980000) { /* |x| < 1.1875 */ |
+ if (ix < 0x3f300000) { /* 7/16 <= |x| < 11/16 */ |
+ id = 0; |
+ x = (2.0f * x - 1.0f) / (2.0f + x); |
+ } else { /* 11/16 <= |x| < 19/16 */ |
+ id = 1; |
+ x = (x - 1.0f) / (x + 1.0f); |
+ } |
+ } else { |
+ if (ix < 0x401c0000) { /* |x| < 2.4375 */ |
+ id = 2; |
+ x = (x - 1.5f) / (1.0f + 1.5f * x); |
+ } else { /* 2.4375 <= |x| < 2**26 */ |
+ id = 3; |
+ x = -1.0f / 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])); |
+ s2 = w * (aT[1] + w * aT[3]); |
+ if (id < 0) |
+ return x - x * (s1 + s2); |
+ z = atanhi[id] - ((x * (s1 + s2) - atanlo[id]) - x); |
+ return sign ? -z : z; |
} |