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| -/* |
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| - * Copyright (c) 2018 Jorge Aparicio |
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| - * |
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| - * Permission is hereby granted, free of charge, to any |
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| - * person obtaining a copy of this software and associated |
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| - * documentation files (the "Software"), to deal in the |
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| - * Software without restriction, including without |
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| - * limitation the rights to use, copy, modify, merge, |
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| - * publish, distribute, sublicense, and/or sell copies of |
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| - * the Software, and to permit persons to whom the Software |
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| - * is furnished to do so, subject to the following |
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| - * conditions: |
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| - * |
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| - * The above copyright notice and this permission notice |
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| - * shall be included in all copies or substantial portions |
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| - * of the Software. |
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| - * |
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| - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF |
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| - * ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED |
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| - * TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A |
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| - * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT |
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| - * SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY |
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| - * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION |
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| - * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR |
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| - * IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER |
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| - * DEALINGS IN THE SOFTWARE. |
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| - */ |
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| - |
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| -use core::f32; |
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| -use core::u32; |
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| - |
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| -#[no_mangle] |
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| -pub fn fmodf(x: f32, y: f32) -> f32 { |
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| - let mut uxi = x.to_bits(); |
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| - let mut uyi = y.to_bits(); |
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| - let mut ex = (uxi >> 23 & 0xff) as i32; |
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| - let mut ey = (uyi >> 23 & 0xff) as i32; |
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| - let sx = uxi & 0x80000000; |
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| - let mut i; |
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| - |
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| - if uyi << 1 == 0 || y.is_nan() || ex == 0xff { |
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| - return (x * y) / (x * y); |
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| - } |
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| - |
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| - if uxi << 1 <= uyi << 1 { |
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| - if uxi << 1 == uyi << 1 { |
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| - return 0.0 * x; |
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| - } |
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| - |
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| - return x; |
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| - } |
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| - |
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| - /* normalize x and y */ |
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| - if ex == 0 { |
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| - i = uxi << 9; |
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| - while i >> 31 == 0 { |
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| - ex -= 1; |
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| - i <<= 1; |
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| - } |
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| - |
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| - uxi <<= -ex + 1; |
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| - } else { |
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| - uxi &= u32::MAX >> 9; |
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| - uxi |= 1 << 23; |
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| - } |
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| - |
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| - if ey == 0 { |
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| - i = uyi << 9; |
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| - while i >> 31 == 0 { |
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| - ey -= 1; |
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| - i <<= 1; |
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| - } |
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| - |
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| - uyi <<= -ey + 1; |
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| - } else { |
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| - uyi &= u32::MAX >> 9; |
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| - uyi |= 1 << 23; |
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| - } |
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| - |
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| - /* x mod y */ |
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| - while ex > ey { |
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| - i = uxi - uyi; |
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| - if i >> 31 == 0 { |
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| - if i == 0 { |
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| - return 0.0 * x; |
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| - } |
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| - uxi = i; |
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| - } |
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| - uxi <<= 1; |
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| - |
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| - ex -= 1; |
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| - } |
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| - |
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| - i = uxi - uyi; |
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| - if i >> 31 == 0 { |
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| - if i == 0 { |
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| - return 0.0 * x; |
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| - } |
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| - uxi = i; |
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| - } |
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| - |
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| - while uxi >> 23 == 0 { |
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| - uxi <<= 1; |
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| - ex -= 1; |
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| - } |
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| - |
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| - /* scale result up */ |
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| - if ex > 0 { |
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| - uxi -= 1 << 23; |
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| - uxi |= (ex as u32) << 23; |
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| - } else { |
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| - uxi >>= -ex + 1; |
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| - } |
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| - uxi |= sx; |
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| - |
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| - f32::from_bits(uxi) |
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| -} |
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| - |
119 | 1 | /* origin: FreeBSD /usr/src/lib/msun/src/e_sqrtf.c */
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120 | 2 | /*
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121 | 3 | * Conversion to float by Ian Lance Taylor, Cygnus Support, [email protected].
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