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-rw-r--r--vendor/libm/src/math/truncf.rs41
1 files changed, 41 insertions, 0 deletions
diff --git a/vendor/libm/src/math/truncf.rs b/vendor/libm/src/math/truncf.rs
new file mode 100644
index 000000000..f93383269
--- /dev/null
+++ b/vendor/libm/src/math/truncf.rs
@@ -0,0 +1,41 @@
+use core::f32;
+
+#[inline]
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn truncf(x: f32) -> f32 {
+ // On wasm32 we know that LLVM's intrinsic will compile to an optimized
+ // `f32.trunc` native instruction, so we can leverage this for both code size
+ // and speed.
+ llvm_intrinsically_optimized! {
+ #[cfg(target_arch = "wasm32")] {
+ return unsafe { ::core::intrinsics::truncf32(x) }
+ }
+ }
+ let x1p120 = f32::from_bits(0x7b800000); // 0x1p120f === 2 ^ 120
+
+ let mut i: u32 = x.to_bits();
+ let mut e: i32 = (i >> 23 & 0xff) as i32 - 0x7f + 9;
+ let m: u32;
+
+ if e >= 23 + 9 {
+ return x;
+ }
+ if e < 9 {
+ e = 1;
+ }
+ m = -1i32 as u32 >> e;
+ if (i & m) == 0 {
+ return x;
+ }
+ force_eval!(x + x1p120);
+ i &= !m;
+ f32::from_bits(i)
+}
+
+#[cfg(test)]
+mod tests {
+ #[test]
+ fn sanity_check() {
+ assert_eq!(super::truncf(1.1), 1.0);
+ }
+}