Fast path.

src/Workspaces/Core/Portable/PatternMatching/PatternMatcher.cs

@@ -331,43 +331,33 @@ private static bool ContainsSpaceOrAsterisk(string text)
             //
             // 2) For each word try to match the word against the candidate value.
             //
-            // 3) Matching is as follows:
-            //
-            //   a) Check if the word matches the candidate entirely, in an case insensitive or
-            //    sensitive manner.  If it does, return that there was an exact match.
-            //
-            //   b) Check if the word is a prefix of the candidate, in a case insensitive or
-            //      sensitive manner.  If it does, return that there was a prefix match.
-            //
-            //   c) If the word is entirely lowercase, then check if it is contained anywhere in the
-            //      candidate in a case insensitive manner.  If so, return that there was a substring
-            //      match. 
-            //
-            //      Note: We only have a substring match if the lowercase part is prefix match of
-            //      some word part. That way we don't match something like 'Class' when the user
-            //      types 'a'. But we would match 'FooAttribute' (since 'Attribute' starts with
-            //      'a').
-            //
-            //   d) If the word was not entirely lowercase, then check if it is contained in the
-            //      candidate in a case *sensitive* manner. If so, return that there was a substring
-            //      match.
-            //
-            //   e) If the word was entirely lowercase, then attempt a special lower cased camel cased 
-            //      match.  i.e. cofipro would match CodeFixProvider.
-            //
-            //   f) If the word was not entirely lowercase, then attempt a normal camel cased match.
-            //      i.e. CoFiPro would match CodeFixProvider, but CofiPro would not.  
-            //
-            //   g) The word is all lower case. Is it a case insensitive substring of the candidate starting 
-            //      on a part boundary of the candidate?
+            // 3) Matching logic is outlined in NonFuzzyMatchPatternChunk. It's not repeated here to
+            //    prevent having multiple places to keep up to date.
             //
             // Only if all words have some sort of match is the pattern considered matched.
 
+            // Special case a simple pattern (alpha-numeric with no spaces).  This is the common
+            // case and we want to prevent unnecessary overhead.
+            var subWordTextChunks = segment.SubWordTextChunks;
+
+            if (subWordTextChunks.Length == 1)
+            {
+                var result = MatchPatternChunk(
+                    candidate, subWordTextChunks[0], punctuationStripped: true, fuzzyMatch: fuzzyMatch);
+                if (result == null)
+                {
+                    return false;
+                }
+
+                matches.Add(result.Value);
+                return true;
+            }
+            else
+            {
                 var tempMatches = ArrayBuilder<PatternMatch>.GetInstance();
 
                 try
                 {
-                var subWordTextChunks = segment.SubWordTextChunks;
                     foreach (var subWordTextChunk in subWordTextChunks)
                     {
                         // Try to match the candidate with this word
@@ -389,6 +379,7 @@ private static bool ContainsSpaceOrAsterisk(string text)
                     tempMatches.Free();
                 }
             }
+        }
 
         private static bool IsWordChar(char ch)
             => char.IsLetterOrDigit(ch) || ch == '_';