| 1 | // [See license/rust-lang/libm] Copyright (c) 2018 Jorge Aparicio |
|---|---|
| 2 | pub fn floor(x: f32) -> f32 { |
| 3 | let mut ui = x.to_bits(); |
| 4 | let e = (((ui >> 23) as i32) & 0xff) - 0x7f; |
| 5 | |
| 6 | if e >= 23 { |
| 7 | return x; |
| 8 | } |
| 9 | if e >= 0 { |
| 10 | let m: u32 = 0x007fffff >> e; |
| 11 | if (ui & m) == 0 { |
| 12 | return x; |
| 13 | } |
| 14 | if ui >> 31 != 0 { |
| 15 | ui += m; |
| 16 | } |
| 17 | ui &= !m; |
| 18 | } else { |
| 19 | if ui >> 31 == 0 { |
| 20 | ui = 0; |
| 21 | } else if ui << 1 != 0 { |
| 22 | return -1.0; |
| 23 | } |
| 24 | } |
| 25 | f32::from_bits(ui) |
| 26 | } |
| 27 |