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-rw-r--r--lib/mlibc/options/ansi/musl-generic-math/tanh.c45
1 files changed, 0 insertions, 45 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/tanh.c b/lib/mlibc/options/ansi/musl-generic-math/tanh.c
deleted file mode 100644
index 20d6dbc..0000000
--- a/lib/mlibc/options/ansi/musl-generic-math/tanh.c
+++ /dev/null
@@ -1,45 +0,0 @@
-#include "libm.h"
-
-/* tanh(x) = (exp(x) - exp(-x))/(exp(x) + exp(-x))
- * = (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;
-
- /* 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;
-}