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-rw-r--r--lib/mlibc/options/ansi/musl-generic-math/atanh.c29
1 files changed, 0 insertions, 29 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/atanh.c b/lib/mlibc/options/ansi/musl-generic-math/atanh.c
deleted file mode 100644
index 63a035d..0000000
--- a/lib/mlibc/options/ansi/musl-generic-math/atanh.c
+++ /dev/null
@@ -1,29 +0,0 @@
-#include "libm.h"
-
-/* atanh(x) = log((1+x)/(1-x))/2 = log1p(2x/(1-x))/2 ~= x + x^3/3 + o(x^5) */
-double atanh(double x)
-{
- union {double f; uint64_t i;} u = {.f = x};
- unsigned e = u.i >> 52 & 0x7ff;
- unsigned s = u.i >> 63;
- double_t y;
-
- /* |x| */
- u.i &= (uint64_t)-1/2;
- y = u.f;
-
- if (e < 0x3ff - 1) {
- if (e < 0x3ff - 32) {
- /* handle underflow */
- if (e == 0)
- FORCE_EVAL((float)y);
- } else {
- /* |x| < 0.5, up to 1.7ulp error */
- y = 0.5*log1p(2*y + 2*y*y/(1-y));
- }
- } else {
- /* avoid overflow */
- y = 0.5*log1p(2*(y/(1-y)));
- }
- return s ? -y : y;
-}