From: David Crawshaw <crawshaw@golang.org>
Date: Thu, 23 Jun 2016 17:32:50 +0000 (-0400)
Subject: reflect: optimize (reflect.Type).Name
X-Git-Tag: go1.7rc1~62
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=e75c899a10c9321d1b4935c34401f66b2abad83a;p=gostls13.git

reflect: optimize (reflect.Type).Name

Improves JSON decoding on linux/amd64.

name                   old time/op    new time/op    delta
CodeUnmarshal-40         89.3ms ± 2%    86.3ms ± 2%  -3.31%  (p=0.000 n=22+22)

name                   old speed      new speed      delta
CodeUnmarshal-40       21.7MB/s ± 2%  22.5MB/s ± 2%  +3.44%  (p=0.000 n=22+22)

Updates #16117

Change-Id: I52acf31d7729400cfe6693e46292d41e1addba3d
Reviewed-on: https://go-review.googlesource.com/24410
Run-TryBot: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
---

diff --git a/src/reflect/type.go b/src/reflect/type.go
index b37fb9f0a5..d60d0b060b 100644
--- a/src/reflect/type.go
+++ b/src/reflect/type.go
@@ -891,25 +891,30 @@ func hasPrefix(s, prefix string) bool {
 
 func (t *rtype) Name() string {
 	s := t.String()
-	if hasPrefix(s, "map[") {
-		return ""
-	}
-	if hasPrefix(s, "struct {") {
-		return ""
-	}
-	if hasPrefix(s, "chan ") {
-		return ""
-	}
-	if hasPrefix(s, "chan<-") {
-		return ""
-	}
-	if hasPrefix(s, "func(") {
-		return ""
-	}
-	if hasPrefix(s, "interface {") {
-		return ""
-	}
 	switch s[0] {
+	case 'm':
+		if hasPrefix(s, "map[") {
+			return ""
+		}
+	case 's':
+		if hasPrefix(s, "struct {") {
+			return ""
+		}
+	case 'c':
+		if hasPrefix(s, "chan ") {
+			return ""
+		}
+		if hasPrefix(s, "chan<-") {
+			return ""
+		}
+	case 'f':
+		if hasPrefix(s, "func(") {
+			return ""
+		}
+	case 'i':
+		if hasPrefix(s, "interface {") {
+			return ""
+		}
 	case '[', '*', '<':
 		return ""
 	}