From 91134e614ef7ae4e758cc894eceaae6054ec5631 Mon Sep 17 00:00:00 2001
From: Jubilee Young <workingjubilee@gmail.com>
Date: Tue, 13 Apr 2021 21:15:20 -0700
Subject: [PATCH] Branchless abs

---
 crates/core_simd/src/math.rs | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/crates/core_simd/src/math.rs b/crates/core_simd/src/math.rs
index baf92ee097bd..50e8f2c10c9b 100644
--- a/crates/core_simd/src/math.rs
+++ b/crates/core_simd/src/math.rs
@@ -91,11 +91,9 @@ macro_rules! impl_int_arith {
             /// ```
             #[inline]
             pub fn abs(self) -> Self {
-                let mut xs = self.to_array();
-                for (i, x) in xs.clone().iter().enumerate() {
-                    xs[i] = x.wrapping_abs()
-                }
-                $name::from_array(xs)
+                const SHR: $n = <$n>::BITS as $n - 1;
+                let m = self >> SHR;
+                (self^m) - m
             }
 
             /// Lanewise saturating absolute value, implemented in Rust.