Changeset 175938 in webkit

Timestamp:

Nov 11, 2014, 9:09:01 AM (12 years ago)

Author:

Carlos Garcia Campos

Message:

Merge r175462 - Reduce the cost of argumentCount checks in the JS bindings
​https://bugs.webkit.org/show_bug.cgi?id=138289

Reviewed by Sam Weinig.

Slightly reduce the cost of argumentCount checks in the JS bindings by
hinting to the compiler that it is UNLIKELY that those methods are
called with too few arguments.

I see a 3% progression on PerformanceTests/DOM/DOMDivWalk.html
performance test.

No new tests, no behavior change.

• bindings/scripts/CodeGeneratorJS.pm:

(GenerateArgumentsCountCheck):

Location:

releases/WebKitGTK/webkit-2.6/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• bindings/scripts/CodeGeneratorJS.pm (modified) (1 diff)

releases/WebKitGTK/webkit-2.6/Source/WebCore/ChangeLog

@@ +1 @@
+2014-11-02  Chris Dumez  <cdumez@apple.com>
+
+        Reduce the cost of argumentCount checks in the JS bindings
+        https://bugs.webkit.org/show_bug.cgi?id=138289
+
+        Reviewed by Sam Weinig.
+
+        Slightly reduce the cost of argumentCount checks in the JS bindings by
+        hinting to the compiler that it is UNLIKELY that those methods are
+        called with too few arguments.
+
+        I see a 3% progression on PerformanceTests/DOM/DOMDivWalk.html
+        performance test.
+
+        No new tests, no behavior change.
+
+        * bindings/scripts/CodeGeneratorJS.pm:
+        (GenerateArgumentsCountCheck):
+
 2014-10-31  Benjamin Poulain  <bpoulain@apple.com>
 

releases/WebKitGTK/webkit-2.6/Source/WebCore/bindings/scripts/CodeGeneratorJS.pm

@@ -3170 +3170 @@
     if ($numMandatoryParams >= 1)
     {
-        push(@$outputArray, "    if (exec->argumentCount() < $numMandatoryParams)\n");
+        push(@$outputArray, "    if (UNLIKELY(exec->argumentCount() < $numMandatoryParams))\n");
         push(@$outputArray, "        return throwVMError(exec, createNotEnoughArgumentsError(exec));\n");
     }