Changeset 42537 in webkit for trunk/JavaScriptCore/interpreter/Interpreter.h

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/interpreter/Interpreter.h (modified) (3 diffs)

trunk/JavaScriptCore/interpreter/Interpreter.h

@@ -68 +68 @@
         friend class JIT;
         friend class JITStubs;
-
+        friend class CachedCall;
     public:
         Interpreter();
@@ -110 +110 @@
     private:
         enum ExecutionFlag { Normal, InitializeAndReturn };
+        
+        struct CallFrameClosure {
+            CallFrame* oldCallFrame;
+            CallFrame* newCallFrame;
+            JSFunction* function;
+            CodeBlock* codeBlock;
+            JSGlobalData* globalData;
+            Register* oldEnd;
+            ScopeChainNode* scopeChain;
+            int expectedParams;
+            int providedParams;
+
+            void setArgument(int arg, JSValuePtr value)
+            {
+                if (arg < expectedParams)
+                    newCallFrame[arg - RegisterFile::CallFrameHeaderSize - expectedParams] = value;
+                else
+                    newCallFrame[arg - RegisterFile::CallFrameHeaderSize - expectedParams - providedParams] = value;
+            }
+            void resetCallFrame()
+            {
+                newCallFrame->setScopeChain(scopeChain);
+                newCallFrame->setCalleeArguments(0);
+                for (int i = providedParams; i < expectedParams; ++i)
+                    newCallFrame[i - RegisterFile::CallFrameHeaderSize - expectedParams] = jsUndefined();
+            }
+        };
+        CallFrameClosure prepareForRepeatCall(FunctionBodyNode*, CallFrame*, JSFunction*, int argCount, ScopeChainNode*, JSValuePtr* exception);
+        void endRepeatCall(CallFrameClosure&);
+        JSValuePtr execute(CallFrameClosure&, JSValuePtr* exception);
 
         NEVER_INLINE JSValuePtr callEval(CallFrame*, RegisterFile*, Register* argv, int argc, int registerOffset, JSValuePtr& exceptionValue);
@@ -154 +184 @@
 #endif
     };
-
+    
 } // namespace JSC