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-rw-r--r--vendor/libm/src/math/scalbnf.rs30
1 files changed, 30 insertions, 0 deletions
diff --git a/vendor/libm/src/math/scalbnf.rs b/vendor/libm/src/math/scalbnf.rs
new file mode 100644
index 000000000..4e9771175
--- /dev/null
+++ b/vendor/libm/src/math/scalbnf.rs
@@ -0,0 +1,30 @@
+#[inline]
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn scalbnf(mut x: f32, mut n: i32) -> f32 {
+ let x1p127 = f32::from_bits(0x7f000000); // 0x1p127f === 2 ^ 127
+ let x1p_126 = f32::from_bits(0x800000); // 0x1p-126f === 2 ^ -126
+ let x1p24 = f32::from_bits(0x4b800000); // 0x1p24f === 2 ^ 24
+
+ if n > 127 {
+ x *= x1p127;
+ n -= 127;
+ if n > 127 {
+ x *= x1p127;
+ n -= 127;
+ if n > 127 {
+ n = 127;
+ }
+ }
+ } else if n < -126 {
+ x *= x1p_126 * x1p24;
+ n += 126 - 24;
+ if n < -126 {
+ x *= x1p_126 * x1p24;
+ n += 126 - 24;
+ if n < -126 {
+ n = -126;
+ }
+ }
+ }
+ x * f32::from_bits(((0x7f + n) as u32) << 23)
+}