From 535efa4afd3bb5a141eae8579f54aa641ccedaa2 Mon Sep 17 00:00:00 2001
From: Phosphorus15 <steepout@qq.com>
Date: Tue, 20 Aug 2019 12:39:12 +0800
Subject: [PATCH] Used `copysign` to avoid unnecessary branches.

---
 src/libstd/f32.rs | 10 +---------
 src/libstd/f64.rs | 10 +---------
 2 files changed, 2 insertions(+), 18 deletions(-)

diff --git a/src/libstd/f32.rs b/src/libstd/f32.rs
index ba75650fc4cb..dcb035993ae3 100644
--- a/src/libstd/f32.rs
+++ b/src/libstd/f32.rs
@@ -910,15 +910,7 @@ impl f32 {
     pub fn asinh(self) -> f32 {
         match self {
             x if x == NEG_INFINITY => NEG_INFINITY,
-            x if x.is_sign_negative() => {
-                let v = (x + ((x * x) + 1.0).sqrt()).ln();
-                if v.is_sign_negative() {
-                    v
-                } else {
-                    -v
-                }
-            }
-            x => (x + ((x * x) + 1.0).sqrt()).ln()
+            x => (x + ((x * x) + 1.0).sqrt()).ln().copysign(self)
         }
     }
 
diff --git a/src/libstd/f64.rs b/src/libstd/f64.rs
index 62c659739de7..076b6340d89b 100644
--- a/src/libstd/f64.rs
+++ b/src/libstd/f64.rs
@@ -833,15 +833,7 @@ impl f64 {
     pub fn asinh(self) -> f64 {
         match self {
             x if x == NEG_INFINITY => NEG_INFINITY,
-            x if x.is_sign_negative() => {
-                let v = (x + ((x * x) + 1.0).sqrt()).ln();
-                if v.is_sign_negative() {
-                    v
-                } else {
-                    -v
-                }
-            }
-            x => (x + ((x * x) + 1.0).sqrt()).ln()
+            x => (x + ((x * x) + 1.0).sqrt()).ln().copysign(self)
         }
     }