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-rw-r--r--vendor/libm/src/math/remquo.rs97
1 files changed, 97 insertions, 0 deletions
diff --git a/vendor/libm/src/math/remquo.rs b/vendor/libm/src/math/remquo.rs
new file mode 100644
index 000000000..1c2ba8918
--- /dev/null
+++ b/vendor/libm/src/math/remquo.rs
@@ -0,0 +1,97 @@
+pub fn remquo(mut x: f64, mut y: f64) -> (f64, i32) {
+ let ux: u64 = x.to_bits();
+ let mut uy: u64 = y.to_bits();
+ let mut ex = ((ux >> 52) & 0x7ff) as i32;
+ let mut ey = ((uy >> 52) & 0x7ff) as i32;
+ let sx = (ux >> 63) != 0;
+ let sy = (uy >> 63) != 0;
+ let mut q: u32;
+ let mut i: u64;
+ let mut uxi: u64 = ux;
+
+ if (uy << 1) == 0 || y.is_nan() || ex == 0x7ff {
+ return ((x * y) / (x * y), 0);
+ }
+ if (ux << 1) == 0 {
+ return (x, 0);
+ }
+
+ /* normalize x and y */
+ if ex == 0 {
+ i = uxi << 12;
+ while (i >> 63) == 0 {
+ ex -= 1;
+ i <<= 1;
+ }
+ uxi <<= -ex + 1;
+ } else {
+ uxi &= (!0) >> 12;
+ uxi |= 1 << 52;
+ }
+ if ey == 0 {
+ i = uy << 12;
+ while (i >> 63) == 0 {
+ ey -= 1;
+ i <<= 1;
+ }
+ uy <<= -ey + 1;
+ } else {
+ uy &= (!0) >> 12;
+ uy |= 1 << 52;
+ }
+
+ q = 0;
+
+ if ex + 1 != ey {
+ if ex < ey {
+ return (x, 0);
+ }
+ /* x mod y */
+ while ex > ey {
+ i = uxi.wrapping_sub(uy);
+ if (i >> 63) == 0 {
+ uxi = i;
+ q += 1;
+ }
+ uxi <<= 1;
+ q <<= 1;
+ ex -= 1;
+ }
+ i = uxi.wrapping_sub(uy);
+ if (i >> 63) == 0 {
+ uxi = i;
+ q += 1;
+ }
+ if uxi == 0 {
+ ex = -60;
+ } else {
+ while (uxi >> 52) == 0 {
+ uxi <<= 1;
+ ex -= 1;
+ }
+ }
+ }
+
+ /* scale result and decide between |x| and |x|-|y| */
+ if ex > 0 {
+ uxi -= 1 << 52;
+ uxi |= (ex as u64) << 52;
+ } else {
+ uxi >>= -ex + 1;
+ }
+ x = f64::from_bits(uxi);
+ if sy {
+ y = -y;
+ }
+ if ex == ey || (ex + 1 == ey && (2.0 * x > y || (2.0 * x == y && (q % 2) != 0))) {
+ x -= y;
+ q += 1;
+ }
+ q &= 0x7fffffff;
+ let quo = if sx ^ sy { -(q as i32) } else { q as i32 };
+ if sx {
+ (-x, quo)
+ } else {
+ (x, quo)
+ }
+}