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 { |
93 | (-x, quo) |
94 | } else { |
95 | (x, quo) |
96 | } |
97 | } |
98 | |