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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/nextafter.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/nextafter.rs')
-rw-r--r--third_party/rust/libm/src/math/nextafter.rs37
1 files changed, 37 insertions, 0 deletions
diff --git a/third_party/rust/libm/src/math/nextafter.rs b/third_party/rust/libm/src/math/nextafter.rs
new file mode 100644
index 0000000000..13094a17c3
--- /dev/null
+++ b/third_party/rust/libm/src/math/nextafter.rs
@@ -0,0 +1,37 @@
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn nextafter(x: f64, y: f64) -> f64 {
+ if x.is_nan() || y.is_nan() {
+ return x + y;
+ }
+
+ let mut ux_i = x.to_bits();
+ let uy_i = y.to_bits();
+ if ux_i == uy_i {
+ return y;
+ }
+
+ let ax = ux_i & !1_u64 / 2;
+ let ay = uy_i & !1_u64 / 2;
+ if ax == 0 {
+ if ay == 0 {
+ return y;
+ }
+ ux_i = (uy_i & 1_u64 << 63) | 1;
+ } else if ax > ay || ((ux_i ^ uy_i) & 1_u64 << 63) != 0 {
+ ux_i -= 1;
+ } else {
+ ux_i += 1;
+ }
+
+ let e = ux_i.wrapping_shr(52 & 0x7ff);
+ // raise overflow if ux.f is infinite and x is finite
+ if e == 0x7ff {
+ force_eval!(x + x);
+ }
+ let ux_f = f64::from_bits(ux_i);
+ // raise underflow if ux.f is subnormal or zero
+ if e == 0 {
+ force_eval!(x * x + ux_f * ux_f);
+ }
+ ux_f
+}