Avoid string concat array allocation in ActivityTracker

justinvp · justinvp · commit 1eede1b3e364 · 2016-07-06T13:03:07.000-07:00
`ActivityTracker+ActivityInfo.ToString()` currently uses
`string.Concat(string[])` which requires a `string[]` allocation.

The `string[]` allocation can be avoided by modifying the code
slightly.
diff --git a/src/mscorlib/src/System/Diagnostics/Eventing/ActivityTracker.cs b/src/mscorlib/src/System/Diagnostics/Eventing/ActivityTracker.cs
@@ -328,10 +328,7 @@ public static string Path(ActivityInfo activityInfo)
 
             public override string ToString()
             {
-                string dead = "";
-                if (m_stopped != 0)
-                    dead = ",DEAD";
-                return m_name + "(" + Path(this) + dead + ")";
+                return m_name + "(" + Path(this) + (m_stopped != 0 ? ",DEAD)" : ")");
             }
 
             public static string LiveActivities(ActivityInfo list)

Original file line number	Diff line number	Diff line change
`@@ -328,10 +328,7 @@ public static string Path(ActivityInfo activityInfo)`
`328`	`328`
`329`	`329`	`public override string ToString()`
`330`	`330`	`{`
`331`		`- string dead = "";`
`332`		`- if (m_stopped != 0)`
`333`		`- dead = ",DEAD";`
`334`		`- return m_name + "(" + Path(this) + dead + ")";`
	`331`	`+ return m_name + "(" + Path(this) + (m_stopped != 0 ? ",DEAD)" : ")");`
`335`	`332`	`}`
`336`	`333`
`337`	`334`	`public static string LiveActivities(ActivityInfo list)`