| 1 | #[cfg_attr (all(test, assert_no_panic), no_panic::no_panic)] |
| 2 | pub fn remquof(mut x: f32, mut y: f32) -> (f32, i32) { |
| 3 | let ux: u32 = x.to_bits(); |
| 4 | let mut uy: u32 = y.to_bits(); |
| 5 | let mut ex = ((ux >> 23) & 0xff) as i32; |
| 6 | let mut ey = ((uy >> 23) & 0xff) as i32; |
| 7 | let sx = (ux >> 31) != 0; |
| 8 | let sy = (uy >> 31) != 0; |
| 9 | let mut q: u32; |
| 10 | let mut i: u32; |
| 11 | let mut uxi: u32 = ux; |
| 12 | |
| 13 | if (uy << 1) == 0 || y.is_nan() || ex == 0xff { |
| 14 | return ((x * y) / (x * y), 0); |
| 15 | } |
| 16 | if (ux << 1) == 0 { |
| 17 | return (x, 0); |
| 18 | } |
| 19 | |
| 20 | /* normalize x and y */ |
| 21 | if ex == 0 { |
| 22 | i = uxi << 9; |
| 23 | while (i >> 31) == 0 { |
| 24 | ex -= 1; |
| 25 | i <<= 1; |
| 26 | } |
| 27 | uxi <<= -ex + 1; |
| 28 | } else { |
| 29 | uxi &= (!0) >> 9; |
| 30 | uxi |= 1 << 23; |
| 31 | } |
| 32 | if ey == 0 { |
| 33 | i = uy << 9; |
| 34 | while (i >> 31) == 0 { |
| 35 | ey -= 1; |
| 36 | i <<= 1; |
| 37 | } |
| 38 | uy <<= -ey + 1; |
| 39 | } else { |
| 40 | uy &= (!0) >> 9; |
| 41 | uy |= 1 << 23; |
| 42 | } |
| 43 | |
| 44 | q = 0; |
| 45 | if ex + 1 != ey { |
| 46 | if ex < ey { |
| 47 | return (x, 0); |
| 48 | } |
| 49 | /* x mod y */ |
| 50 | while ex > ey { |
| 51 | i = uxi.wrapping_sub(uy); |
| 52 | if (i >> 31) == 0 { |
| 53 | uxi = i; |
| 54 | q += 1; |
| 55 | } |
| 56 | uxi <<= 1; |
| 57 | q <<= 1; |
| 58 | ex -= 1; |
| 59 | } |
| 60 | i = uxi.wrapping_sub(uy); |
| 61 | if (i >> 31) == 0 { |
| 62 | uxi = i; |
| 63 | q += 1; |
| 64 | } |
| 65 | if uxi == 0 { |
| 66 | ex = -30; |
| 67 | } else { |
| 68 | while (uxi >> 23) == 0 { |
| 69 | uxi <<= 1; |
| 70 | ex -= 1; |
| 71 | } |
| 72 | } |
| 73 | } |
| 74 | |
| 75 | /* scale result and decide between |x| and |x|-|y| */ |
| 76 | if ex > 0 { |
| 77 | uxi -= 1 << 23; |
| 78 | uxi |= (ex as u32) << 23; |
| 79 | } else { |
| 80 | uxi >>= -ex + 1; |
| 81 | } |
| 82 | x = f32::from_bits(uxi); |
| 83 | if sy { |
| 84 | y = -y; |
| 85 | } |
| 86 | if ex == ey || (ex + 1 == ey && (2.0 * x > y || (2.0 * x == y && (q % 2) != 0))) { |
| 87 | x -= y; |
| 88 | q += 1; |
| 89 | } |
| 90 | q &= 0x7fffffff; |
| 91 | let quo = if sx ^ sy { -(q as i32) } else { q as i32 }; |
| 92 | if sx { (-x, quo) } else { (x, quo) } |
| 93 | } |
| 94 | |