mq_notify: block all (application) signals in the worker thread

[musl] / src / math / tanh.c

diff --git a/src/math/tanh.c b/src/math/tanh.c
index 0e766c5..20d6dbc 100644 (file)
--- a/src/math/tanh.c
+++ b/src/math/tanh.c
@@ -9,7 +9,7 @@ double tanh(double x)
        union {double f; uint64_t i;} u = {.f = x};
        uint32_t w;
        int sign;
-       double t;
+       double_t t;
 
        /* x = |x| */
        sign = u.i >> 63;
@@ -22,8 +22,7 @@ double tanh(double x)
                if (w > 0x40340000) {
                        /* |x| > 20 or nan */
                        /* note: this branch avoids raising overflow */
-                       /* raise inexact if x!=+-inf and handle nan */
-                       t = 1 + 0/(x + 0x1p-120f);
+                       t = 1 - 0/x;
                } else {
                        t = expm1(2*x);
                        t = 1 - 2/(t+2);
@@ -32,10 +31,15 @@ double tanh(double x)
                /* |x| > log(5/3)/2 ~= 0.2554 */
                t = expm1(2*x);
                t = t/(t+2);
-       } else {
-               /* |x| is small, up to 2ulp error in [0.1,0.2554] */
+       } 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;
 }