94 lines
2.1 KiB
Rust
94 lines
2.1 KiB
Rust
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#[cfg_attr(assert_no_panic, no_panic::no_panic)]
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pub fn remquof(mut x: f32, mut y: f32) -> (f32, i32) {
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let ux: u32 = x.to_bits();
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let mut uy: u32 = y.to_bits();
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let mut ex = ((ux >> 23) & 0xff) as i32;
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let mut ey = ((uy >> 23) & 0xff) as i32;
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let sx = (ux >> 31) != 0;
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let sy = (uy >> 31) != 0;
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let mut q: u32;
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let mut i: u32;
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let mut uxi: u32 = ux;
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if (uy << 1) == 0 || y.is_nan() || ex == 0xff {
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return ((x * y) / (x * y), 0);
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}
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if (ux << 1) == 0 {
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return (x, 0);
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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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uxi <<= -ex + 1;
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} else {
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uxi &= (!0) >> 9;
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uxi |= 1 << 23;
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}
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if ey == 0 {
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i = uy << 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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uy <<= -ey + 1;
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} else {
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uy &= (!0) >> 9;
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uy |= 1 << 23;
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}
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q = 0;
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if ex + 1 != ey {
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if ex < ey {
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return (x, 0);
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}
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/* x mod y */
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while ex > ey {
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i = uxi.wrapping_sub(uy);
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if (i >> 31) == 0 {
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uxi = i;
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q += 1;
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}
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uxi <<= 1;
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q <<= 1;
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ex -= 1;
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}
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i = uxi.wrapping_sub(uy);
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if (i >> 31) == 0 {
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uxi = i;
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q += 1;
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}
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if uxi == 0 {
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ex = -30;
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} else {
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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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}
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/* scale result and decide between |x| and |x|-|y| */
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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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x = f32::from_bits(uxi);
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if sy {
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y = -y;
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}
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if ex == ey || (ex + 1 == ey && (2.0 * x > y || (2.0 * x == y && (q % 2) != 0))) {
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x -= y;
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q += 1;
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}
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q &= 0x7fffffff;
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let quo = if sx ^ sy { -(q as i32) } else { q as i32 };
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if sx { (-x, quo) } else { (x, quo) }
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}
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