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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /third_party/rust/libm/src/math/tanhf.rs
parentInitial commit. (diff)
downloadfirefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz
firefox-26a029d407be480d791972afb5975cf62c9360a6.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/libm/src/math/tanhf.rs')
-rw-r--r--third_party/rust/libm/src/math/tanhf.rs39
1 files changed, 39 insertions, 0 deletions
diff --git a/third_party/rust/libm/src/math/tanhf.rs b/third_party/rust/libm/src/math/tanhf.rs
new file mode 100644
index 0000000000..fc94e3ddd5
--- /dev/null
+++ b/third_party/rust/libm/src/math/tanhf.rs
@@ -0,0 +1,39 @@
+use super::expm1f;
+
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn tanhf(mut x: f32) -> f32 {
+ /* x = |x| */
+ let mut ix = x.to_bits();
+ let sign = (ix >> 31) != 0;
+ ix &= 0x7fffffff;
+ x = f32::from_bits(ix);
+ let w = ix;
+
+ let tt = if w > 0x3f0c9f54 {
+ /* |x| > log(3)/2 ~= 0.5493 or nan */
+ if w > 0x41200000 {
+ /* |x| > 10 */
+ 1. + 0. / x
+ } else {
+ let t = expm1f(2. * x);
+ 1. - 2. / (t + 2.)
+ }
+ } else if w > 0x3e82c578 {
+ /* |x| > log(5/3)/2 ~= 0.2554 */
+ let t = expm1f(2. * x);
+ t / (t + 2.)
+ } else if w >= 0x00800000 {
+ /* |x| >= 0x1p-126 */
+ let t = expm1f(-2. * x);
+ -t / (t + 2.)
+ } else {
+ /* |x| is subnormal */
+ force_eval!(x * x);
+ x
+ };
+ if sign {
+ -tt
+ } else {
+ tt
+ }
+}