Index: fusl/src/math/tanh.c |
diff --git a/fusl/src/math/tanh.c b/fusl/src/math/tanh.c |
index 20d6dbcf4175c7aad93fe70a53056f0d3e1c4f13..13fe2f6b6ee8a479acdf83e903a1859cf7051aeb 100644 |
--- a/fusl/src/math/tanh.c |
+++ b/fusl/src/math/tanh.c |
@@ -4,42 +4,45 @@ |
* = (exp(2*x) - 1)/(exp(2*x) - 1 + 2) |
* = (1 - exp(-2*x))/(exp(-2*x) - 1 + 2) |
*/ |
-double tanh(double x) |
-{ |
- union {double f; uint64_t i;} u = {.f = x}; |
- uint32_t w; |
- int sign; |
- double_t t; |
+double tanh(double x) { |
+ union { |
+ double f; |
+ uint64_t i; |
+ } u = {.f = x}; |
+ uint32_t w; |
+ int sign; |
+ double_t t; |
- /* x = |x| */ |
- sign = u.i >> 63; |
- u.i &= (uint64_t)-1/2; |
- x = u.f; |
- w = u.i >> 32; |
+ /* x = |x| */ |
+ sign = u.i >> 63; |
+ u.i &= (uint64_t)-1 / 2; |
+ x = u.f; |
+ w = u.i >> 32; |
- if (w > 0x3fe193ea) { |
- /* |x| > log(3)/2 ~= 0.5493 or nan */ |
- if (w > 0x40340000) { |
- /* |x| > 20 or nan */ |
- /* note: this branch avoids raising overflow */ |
- t = 1 - 0/x; |
- } else { |
- t = expm1(2*x); |
- t = 1 - 2/(t+2); |
- } |
- } else if (w > 0x3fd058ae) { |
- /* |x| > log(5/3)/2 ~= 0.2554 */ |
- t = expm1(2*x); |
- t = t/(t+2); |
- } else if (w >= 0x00100000) { |
- /* |x| >= 0x1p-1022, up to 2ulp error in [0.1,0.2554] */ |
- t = expm1(-2*x); |
- t = -t/(t+2); |
- } else { |
- /* |x| is subnormal */ |
- /* note: the branch above would not raise underflow in [0x1p-1023,0x1p-1022) */ |
- FORCE_EVAL((float)x); |
- t = x; |
- } |
- return sign ? -t : t; |
+ if (w > 0x3fe193ea) { |
+ /* |x| > log(3)/2 ~= 0.5493 or nan */ |
+ if (w > 0x40340000) { |
+ /* |x| > 20 or nan */ |
+ /* note: this branch avoids raising overflow */ |
+ t = 1 - 0 / x; |
+ } else { |
+ t = expm1(2 * x); |
+ t = 1 - 2 / (t + 2); |
+ } |
+ } else if (w > 0x3fd058ae) { |
+ /* |x| > log(5/3)/2 ~= 0.2554 */ |
+ t = expm1(2 * x); |
+ t = t / (t + 2); |
+ } else if (w >= 0x00100000) { |
+ /* |x| >= 0x1p-1022, up to 2ulp error in [0.1,0.2554] */ |
+ t = expm1(-2 * x); |
+ t = -t / (t + 2); |
+ } else { |
+ /* |x| is subnormal */ |
+ /* note: the branch above would not raise underflow in [0x1p-1023,0x1p-1022) |
+ */ |
+ FORCE_EVAL((float)x); |
+ t = x; |
+ } |
+ return sign ? -t : t; |
} |