Changeset 42065 in webkit for trunk/JavaScriptCore/parser

Timestamp:

Mar 27, 2009, 8:50:39 PM (16 years ago)

Author:

[email protected]

Message:

Improve performance of Function.prototype.call
<​https://bugs.webkit.org/show_bug.cgi?id=24907>

Reviewed by Gavin Barraclough

Optimistically assume that expression.call(..) is going to be a call to
Function.prototype.call, and handle it specially to attempt to reduce the
degree of VM reentrancy.

When everything goes right this removes the vm reentry improving .call()
by around a factor of 10.

Location:

trunk/JavaScriptCore/parser

Files:

• Grammar.y (modified) (1 diff)
• Nodes.cpp (modified) (1 diff)
• Nodes.h (modified) (1 diff)

trunk/JavaScriptCore/parser/Grammar.y

@@ -1926 +1926 @@
     ASSERT(func.m_node->isDotAccessorNode());
     DotAccessorNode* dot = static_cast<DotAccessorNode*>(func.m_node);
-    FunctionCallDotNode* node = new FunctionCallDotNode(GLOBAL_DATA, dot->base(), dot->identifier(), args.m_node, divot, divot - start, end - divot);
+    FunctionCallDotNode* node;
+    if (dot->identifier() == GLOBAL_DATA->propertyNames->call)
+        node = new CallFunctionCallDotNode(GLOBAL_DATA, dot->base(), dot->identifier(), args.m_node, divot, divot - start, end - divot);
+    else
+        node = new FunctionCallDotNode(GLOBAL_DATA, dot->base(), dot->identifier(), args.m_node, divot, divot - start, end - divot);
     node->setSubexpressionInfo(dot->divot(), dot->endOffset());
     return createNodeInfo<ExpressionNode*>(node, features, numConstants);

trunk/JavaScriptCore/parser/Nodes.cpp

@@ -693 +693 @@
     RefPtr<RegisterID> thisRegister = generator.emitMove(generator.newTemporary(), base.get());
     return generator.emitCall(generator.finalDestination(dst, function.get()), function.get(), thisRegister.get(), m_args.get(), divot(), startOffset(), endOffset());
+}
+
+RegisterID* CallFunctionCallDotNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
+{
+    RefPtr<Label> realCall = generator.newLabel();
+    RefPtr<Label> end = generator.newLabel();
+    RefPtr<RegisterID> base = generator.emitNode(m_base.get());
+    generator.emitExpressionInfo(divot() - m_subexpressionDivotOffset, startOffset() - m_subexpressionDivotOffset, m_subexpressionEndOffset);
+    RefPtr<RegisterID> function = generator.emitGetById(generator.tempDestination(dst), base.get(), m_ident);
+    RefPtr<RegisterID> finalDestination = generator.finalDestination(dst, function.get());
+    generator.emitJumpIfNotFunctionCall(function.get(), realCall.get());
+    {
+        RefPtr<RegisterID> realFunction = generator.emitMove(generator.tempDestination(dst), base.get());
+        RefPtr<RegisterID> thisRegister = generator.newTemporary();
+        RefPtr<ArgumentListNode> oldList = m_args->m_listNode;
+        if (m_args->m_listNode && m_args->m_listNode->m_expr) {
+            generator.emitNode(thisRegister.get(), m_args->m_listNode->m_expr.get());
+            m_args->m_listNode = m_args->m_listNode->m_next;
+        } else {
+            generator.emitLoad(thisRegister.get(), jsNull());
+        }
+        generator.emitCall(finalDestination.get(), realFunction.get(), thisRegister.get(), m_args.get(), divot(), startOffset(), endOffset());
+        generator.emitJump(end.get());
+        m_args->m_listNode = oldList;
+    }
+    generator.emitLabel(realCall.get());
+    {
+        RefPtr<RegisterID> thisRegister = generator.emitMove(generator.newTemporary(), base.get());
+        generator.emitCall(finalDestination.get(), function.get(), thisRegister.get(), m_args.get(), divot(), startOffset(), endOffset());
+    }
+    generator.emitLabel(end.get());
+    return finalDestination.get();
 }
 

trunk/JavaScriptCore/parser/Nodes.h

@@ -764 +764 @@
         virtual RegisterID* emitBytecode(BytecodeGenerator&, RegisterID* = 0) JSC_FAST_CALL;
 
-    private:
+    protected:
         RefPtr<ExpressionNode> m_base;
         Identifier m_ident;
         RefPtr<ArgumentsNode> m_args;
+    };
+
+    class CallFunctionCallDotNode : public FunctionCallDotNode {
+    public:
+        CallFunctionCallDotNode(JSGlobalData* globalData, ExpressionNode* base, const Identifier& ident, ArgumentsNode* args, unsigned divot, unsigned startOffset, unsigned endOffset) JSC_FAST_CALL
+            : FunctionCallDotNode(globalData, base, ident, args, divot, startOffset, endOffset)
+        {
+        }
+        virtual RegisterID* emitBytecode(BytecodeGenerator&, RegisterID* = 0) JSC_FAST_CALL;
     };