From: kakulisen <lziqiang1@gmail.com>
Date: Thu, 14 May 2020 08:20:58 +0000 (+0800)
Subject: math: simplify the code
X-Git-Tag: go1.16beta1~1356
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=441b52f5660ccde7848f034ba345d2f0088ea383;p=gostls13.git

math: simplify the code

Simplifying some code without compromising performance.
My CPU is Intel Xeon Gold 6161, 2.20GHz, 64-bit operating system.
The memory is 8GB. This is my test environment, I hope to help you judge.

Benchmark:

name      old time/op    new time/op    delta
Log1p-4    21.8ns ± 5%    21.8ns ± 4%   ~     (p=0.973 n=20+20)

Change-Id: Icd8f96f1325b00007602d114300b92d4c57de409
Reviewed-on: https://go-review.googlesource.com/c/go/+/233940
Reviewed-by: Robert Griesemer <gri@golang.org>
---

diff --git a/src/math/log1p.go b/src/math/log1p.go
index c4ec61b225..e34e1ff4f2 100644
--- a/src/math/log1p.go
+++ b/src/math/log1p.go
@@ -122,10 +122,7 @@ func log1p(x float64) float64 {
 		return Inf(1)
 	}
 
-	absx := x
-	if absx < 0 {
-		absx = -absx
-	}
+	absx := Abs(x)
 
 	var f float64
 	var iu uint64