1 files changed, 38 insertions, 0 deletions
diff --git a/vendor/libm-0.1.4/src/math/asinhf.rs b/vendor/libm-0.1.4/src/math/asinhf.rs
new file mode 100644
index 000000000..e22a29132
--- /dev/null
+++ b/vendor/libm-0.1.4/src/math/asinhf.rs
@@ -0,0 +1,38 @@
+use super::{log1pf, logf, sqrtf};
+
+const LN2: f32 = 0.693147180559945309417232121458176568;
+
+/* asinh(x) = sign(x)*log(|x|+sqrt(x*x+1)) ~= x - x^3/6 + o(x^5) */
+/// Inverse hyperbolic sine (f32)
+///
+/// Calculates the inverse hyperbolic sine of `x`.
+/// Is defined as `sgn(x)*log(|x|+sqrt(x*x+1))`.
+pub fn asinhf(mut x: f32) -> f32 {
+    let u = x.to_bits();
+    let i = u & 0x7fffffff;
+    let sign = (u >> 31) != 0;
+
+    /* |x| */
+    x = f32::from_bits(i);
+
+    if i >= 0x3f800000 + (12 << 23) {
+        /* |x| >= 0x1p12 or inf or nan */
+        x = logf(x) + LN2;
+    } else if i >= 0x3f800000 + (1 << 23) {
+        /* |x| >= 2 */
+        x = logf(2.0 * x + 1.0 / (sqrtf(x * x + 1.0) + x));
+    } else if i >= 0x3f800000 - (12 << 23) {
+        /* |x| >= 0x1p-12, up to 1.6ulp error in [0.125,0.5] */
+        x = log1pf(x + x * x / (sqrtf(x * x + 1.0) + 1.0));
+    } else {
+        /* |x| < 0x1p-12, raise inexact if x!=0 */
+        let x1p120 = f32::from_bits(0x7b800000);
+        force_eval!(x + x1p120);
+    }
+
+    if sign {
+        -x
+    } else {
+        x
+    }
+}