diff options
Diffstat (limited to 'vendor/libm/src/math/scalbnf.rs')
-rw-r--r-- | vendor/libm/src/math/scalbnf.rs | 30 |
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) +} |