Changeset 30177 in webkit for trunk/JavaScriptCore

Timestamp:

Feb 12, 2008, 1:29:51 PM (17 years ago)

Author:

[email protected]

Message:

Reviewed by Brady Eidson.

<rdar://problem/5659216> REGRESSION: PLT 0.3% slower due to r28868 (caching ClassNodeList and NamedNodeList)

• Tweak the statements in isASCIISpace to account for the statistical distribution of usage in the PLT.

.4% speedup on my machine. Stephanie's machine shows this as .3% speedup.

• wtf/ASCIICType.h: (WTF::isASCIISpace):

Location:

trunk/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• wtf/ASCIICType.h (modified) (2 diffs)

trunk/JavaScriptCore/ChangeLog

@@ +1 @@
+2008-02-08  Samuel Weinig  <[email protected]>
+
+        Reviewed by Brady Eidson.
+
+        <rdar://problem/5659216> REGRESSION: PLT 0.3% slower due to r28868 (caching ClassNodeList and NamedNodeList)
+
+        - Tweak the statements in isASCIISpace to account for the statistical distribution of
+          usage in the PLT.
+
+        .4% speedup on my machine.  Stephanie's machine shows this as .3% speedup.
+
+        * wtf/ASCIICType.h:
+        (WTF::isASCIISpace): 
+
 2008-02-11  Sam Weinig  <[email protected]>
 

trunk/JavaScriptCore/wtf/ASCIICType.h

@@ -1 +1 @@
 /*
- * Copyright (C) 2007 Apple Inc. All rights reserved.
+ * Copyright (C) 2007, 2008 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -86 +86 @@
     inline bool isASCIIUpper(int c) { return c >= 'A' && c <= 'Z'; }
 
-    inline bool isASCIISpace(char c) { return c == '\t' || c == '\n' || c == '\v' || c =='\f' || c == '\r' || c == ' '; }
-    inline bool isASCIISpace(unsigned short c) { return c == '\t' || c == '\n' || c == '\v' || c =='\f' || c == '\r' || c == ' '; }
+    /*
+        Statistics from a run of the PLT on the usage of isASCIISpace:
+        Hex  Name               Count
+        ---  ----               -----
+           ALL OTHER VALUES     689383
+        x20  SPACE              294720
+        x0A  NEWLINE            89059
+        x09  TAB                28320
+        x0D  CARRIAGE RETURN    0
+        x0C  FORMFEED           0
+        x0B  VERTICAL TAB       0
+
+    */
+
+    inline bool isASCIISpace(char c) { return c <= ' ' && (c == ' ' || (c <= 0xD && c >= 0x9)); }
+    inline bool isASCIISpace(unsigned short c) { return c <= ' ' && (c == ' ' || (c <= 0xD && c >= 0x9)); }
 #if !COMPILER(MSVC) || defined(_NATIVE_WCHAR_T_DEFINED)
-    inline bool isASCIISpace(wchar_t c) { return c == '\t' || c == '\n' || c == '\v' || c =='\f' || c == '\r' || c == ' '; }
+    inline bool isASCIISpace(wchar_t c) { return c <= ' ' && (c == ' ' || (c <= 0xD && c >= 0x9)); }
 #endif
-    inline bool isASCIISpace(int c) { return c == '\t' || c == '\n' || c == '\v' || c =='\f' || c == '\r' || c == ' '; }
+    inline bool isASCIISpace(int c) { return c <= ' ' && (c == ' ' || (c <= 0xD && c >= 0x9)); }
 
     inline char toASCIILower(char c) { return c | ((c >= 'A' && c <= 'Z') << 5); }