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-rw-r--r--vendor/compiler_builtins/libm/src/math/sinh.rs49
1 files changed, 49 insertions, 0 deletions
diff --git a/vendor/compiler_builtins/libm/src/math/sinh.rs b/vendor/compiler_builtins/libm/src/math/sinh.rs
new file mode 100644
index 000000000..fd24fd20c
--- /dev/null
+++ b/vendor/compiler_builtins/libm/src/math/sinh.rs
@@ -0,0 +1,49 @@
+use super::{expm1, expo2};
+
+// sinh(x) = (exp(x) - 1/exp(x))/2
+// = (exp(x)-1 + (exp(x)-1)/exp(x))/2
+// = x + x^3/6 + o(x^5)
+//
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn sinh(x: f64) -> f64 {
+ // union {double f; uint64_t i;} u = {.f = x};
+ // uint32_t w;
+ // double t, h, absx;
+
+ let mut uf: f64 = x;
+ let mut ui: u64 = f64::to_bits(uf);
+ let w: u32;
+ let t: f64;
+ let mut h: f64;
+ let absx: f64;
+
+ h = 0.5;
+ if ui >> 63 != 0 {
+ h = -h;
+ }
+ /* |x| */
+ ui &= !1 / 2;
+ uf = f64::from_bits(ui);
+ absx = uf;
+ w = (ui >> 32) as u32;
+
+ /* |x| < log(DBL_MAX) */
+ if w < 0x40862e42 {
+ t = expm1(absx);
+ if w < 0x3ff00000 {
+ if w < 0x3ff00000 - (26 << 20) {
+ /* note: inexact and underflow are raised by expm1 */
+ /* note: this branch avoids spurious underflow */
+ return x;
+ }
+ return h * (2.0 * t - t * t / (t + 1.0));
+ }
+ /* note: |x|>log(0x1p26)+eps could be just h*exp(x) */
+ return h * (t + t / (t + 1.0));
+ }
+
+ /* |x| > log(DBL_MAX) or nan */
+ /* note: the result is stored to handle overflow */
+ t = 2.0 * h * expo2(absx);
+ t
+}