Changeset 42537 in webkit for trunk/JavaScriptCore/runtime

Timestamp:

Apr 15, 2009, 12:13:25 AM (16 years ago)

Author:

[email protected]

Message:

Bug 25202: Improve performance of repeated callbacks into the VM

Reviewed by Cameron Zwarich

Add the concept of a CachedCall to native code for use in Array
prototype and similar functions where a single callback function
is called repeatedly with the same number of arguments.

Used Array.prototype.filter as the test function and got a 50% win
over a naive non-caching specialised version. This makes the native
implementation of Array.prototype.filter faster than the JS one once
more.

File:

• trunk/JavaScriptCore/runtime/ArrayPrototype.cpp (modified) (2 diffs)

trunk/JavaScriptCore/runtime/ArrayPrototype.cpp

@@ -26 +26 @@
 
 #include "CodeBlock.h"
+#include "CachedCall.h"
 #include "Interpreter.h"
 #include "JIT.h"
@@ -586 +587 @@
     unsigned filterIndex = 0;
     unsigned length = thisObj->get(exec, exec->propertyNames().length).toUInt32(exec);
-    for (unsigned k = 0; k < length && !exec->hadException(); ++k) {
-        PropertySlot slot(thisObj);
-
-        if (!thisObj->getPropertySlot(exec, k, slot))
-            continue;
-
-        JSValuePtr v = slot.getValue(exec, k);
-
-        ArgList eachArguments;
-
-        eachArguments.append(v);
-        eachArguments.append(jsNumber(exec, k));
-        eachArguments.append(thisObj);
-
-        JSValuePtr result = call(exec, function, callType, callData, applyThis, eachArguments);
-
-        if (result.toBoolean(exec))
-            resultArray->put(exec, filterIndex++, v);
+    if (callType == CallTypeHost || !isJSArray(&exec->globalData(), thisObj) || !asArray(thisObj)->canGetIndex(length - 1)) {
+        for (unsigned k = 0; k < length && !exec->hadException(); ++k) {
+            PropertySlot slot(thisObj);
+            
+            if (!thisObj->getPropertySlot(exec, k, slot))
+                continue;
+
+            JSValuePtr v = slot.getValue(exec, k);
+
+            ArgList eachArguments;
+
+            eachArguments.append(v);
+            eachArguments.append(jsNumber(exec, k));
+            eachArguments.append(thisObj);
+
+            JSValuePtr result = call(exec, function, callType, callData, applyThis, eachArguments);
+
+            if (result.toBoolean(exec))
+                resultArray->put(exec, filterIndex++, v);
+        }
+    } else {
+        JSFunction* f = asFunction(function);
+        JSArray* array = asArray(thisObj);
+        CachedCall cachedCall(exec, f, 3, exec->exceptionSlot());
+        for (unsigned k = 0; k < length && !exec->hadException(); ++k) {            
+            JSValuePtr v = array->getIndex(k);
+            cachedCall.setThis(applyThis);
+            cachedCall.setArgument(0, v);
+            cachedCall.setArgument(1, jsNumber(exec, k));
+            cachedCall.setArgument(2, thisObj);
+
+            JSValuePtr result = cachedCall.call();
+            if (result.toBoolean(exec))
+                resultArray->put(exec, filterIndex++, v);
+        }
     }
     return resultArray;