Changeset 45106 in webkit for trunk/JavaScriptCore/parser

Timestamp:

Jun 24, 2009, 3:01:34 PM (16 years ago)

Author:

[email protected]

Message:

<rdar://problem/6940519> REGRESSION (Safari 4 Public Beta - TOT): google.com/adplanner shows blank page instead of site details in "basic research'

Reviewed by Darin Adler.

The problem was caused by the page returned with a function using a
var declaration list containing around ~3000 variables. The solution
to this is to flatten the comma expression representation and make
codegen comma expressions and initializer lists iterative rather than
recursive.

Location:

trunk/JavaScriptCore/parser

Files:

• Grammar.y (modified) (5 diffs)
• NodeConstructors.h (modified) (1 diff)
• Nodes.cpp (modified) (1 diff)
• Nodes.h (modified) (3 diffs)

trunk/JavaScriptCore/parser/Grammar.y

@@ -81 +81 @@
 static ExpressionNode* makeRightShiftNode(void*, ExpressionNode*, ExpressionNode*, bool rightHasAssignments);
 static StatementNode* makeVarStatementNode(void*, ExpressionNode*);
-static ExpressionNode* combineVarInitializers(void*, ExpressionNode* list, AssignResolveNode* init);
+static ExpressionNode* combineCommaNodes(void*, ExpressionNode* list, ExpressionNode* init);
 
 #if COMPILER(MSVC)
@@ -779 +779 @@
 Expr:
     AssignmentExpr
-  | Expr ',' AssignmentExpr             { $$ = createNodeInfo<ExpressionNode*>(new (GLOBAL_DATA) CommaNode(GLOBAL_DATA, $1.m_node, $3.m_node), $1.m_features | $3.m_features, $1.m_numConstants + $3.m_numConstants); }
+  | Expr ',' AssignmentExpr             { $$ = createNodeInfo<ExpressionNode*>(combineCommaNodes(GLOBAL_DATA, $1.m_node, $3.m_node), $1.m_features | $3.m_features, $1.m_numConstants + $3.m_numConstants); }
 ;
 
 ExprNoIn:
     AssignmentExprNoIn
-  | ExprNoIn ',' AssignmentExprNoIn     { $$ = createNodeInfo<ExpressionNode*>(new (GLOBAL_DATA) CommaNode(GLOBAL_DATA, $1.m_node, $3.m_node), $1.m_features | $3.m_features, $1.m_numConstants + $3.m_numConstants); }
+  | ExprNoIn ',' AssignmentExprNoIn     { $$ = createNodeInfo<ExpressionNode*>(combineCommaNodes(GLOBAL_DATA, $1.m_node, $3.m_node), $1.m_features | $3.m_features, $1.m_numConstants + $3.m_numConstants); }
 ;
 
 ExprNoBF:
     AssignmentExprNoBF
-  | ExprNoBF ',' AssignmentExpr         { $$ = createNodeInfo<ExpressionNode*>(new (GLOBAL_DATA) CommaNode(GLOBAL_DATA, $1.m_node, $3.m_node), $1.m_features | $3.m_features, $1.m_numConstants + $3.m_numConstants); }
+  | ExprNoBF ',' AssignmentExpr         { $$ = createNodeInfo<ExpressionNode*>(combineCommaNodes(GLOBAL_DATA, $1.m_node, $3.m_node), $1.m_features | $3.m_features, $1.m_numConstants + $3.m_numConstants); }
 ;
 
@@ -855 +855 @@
                                         { AssignResolveNode* node = new (GLOBAL_DATA) AssignResolveNode(GLOBAL_DATA, *$3, $4.m_node, $4.m_features & AssignFeature);
                                           SET_EXCEPTION_LOCATION(node, @3.first_column, @4.first_column + 1, @4.last_column);
-                                          $$.m_node = combineVarInitializers(GLOBAL_DATA, $1.m_node, node);
+                                          $$.m_node = combineCommaNodes(GLOBAL_DATA, $1.m_node, node);
                                           $$.m_varDeclarations = $1.m_varDeclarations;
                                           appendToVarDeclarationList(GLOBAL_DATA, $$.m_varDeclarations, *$3, DeclarationStacks::HasInitializer);
@@ -892 +892 @@
                                         { AssignResolveNode* node = new (GLOBAL_DATA) AssignResolveNode(GLOBAL_DATA, *$3, $4.m_node, $4.m_features & AssignFeature);
                                           SET_EXCEPTION_LOCATION(node, @3.first_column, @4.first_column + 1, @4.last_column);
-                                          $$.m_node = combineVarInitializers(GLOBAL_DATA, $1.m_node, node);
+                                          $$.m_node = combineCommaNodes(GLOBAL_DATA, $1.m_node, node);
                                           $$.m_varDeclarations = $1.m_varDeclarations;
                                           appendToVarDeclarationList(GLOBAL_DATA, $$.m_varDeclarations, *$3, DeclarationStacks::HasInitializer);
@@ -2072 +2072 @@
 }
 
-static ExpressionNode* combineVarInitializers(void* globalPtr, ExpressionNode* list, AssignResolveNode* init)
+static ExpressionNode* combineCommaNodes(void* globalPtr, ExpressionNode* list, ExpressionNode* init)
 {
     if (!list)
         return init;
+    if (list->isCommaNode()) {
+        static_cast<CommaNode*>(list)->append(init);
+        return list;
+    }
     return new (GLOBAL_DATA) CommaNode(GLOBAL_DATA, list, init);
 }

trunk/JavaScriptCore/parser/NodeConstructors.h

@@ -660 +660 @@
     inline CommaNode::CommaNode(JSGlobalData* globalData, ExpressionNode* expr1, ExpressionNode* expr2)
         : ExpressionNode(globalData)
-        , m_expr1(expr1)
-        , m_expr2(expr2)
-    {
+    {
+        m_expressions.append(expr1);
+        m_expressions.append(expr2);
     }
 

trunk/JavaScriptCore/parser/Nodes.cpp

@@ -1187 +1187 @@
 RegisterID* CommaNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    generator.emitNode(generator.ignoredResult(), m_expr1);
-    return generator.emitNode(dst, m_expr2);
+    ASSERT(m_expressions.size() > 1);
+    for (size_t i = 0; i < m_expressions.size() - 1; i++)
+        generator.emitNode(generator.ignoredResult(), m_expressions[i]);
+    return generator.emitNode(dst, m_expressions.last());
 }
 

trunk/JavaScriptCore/parser/Nodes.h

@@ -170 +170 @@
         virtual bool isBracketAccessorNode() const { return false; }
         virtual bool isDotAccessorNode() const { return false; }
-        virtual bool isFuncExprNode() const { return false; } 
+        virtual bool isFuncExprNode() const { return false; }
+        virtual bool isCommaNode() const { return false; }
         virtual bool isSimpleArray() const { return false; }
         virtual bool isAdd() const { return false; }
@@ -1088 +1089 @@
         ExpressionNode* m_right;
     };
+    
+    typedef Vector<ExpressionNode*, 8> ExpressionVector;
 
     class CommaNode : public ExpressionNode {
@@ -1093 +1096 @@
         CommaNode(JSGlobalData*, ExpressionNode* expr1, ExpressionNode* expr2);
 
-    private:
-        virtual RegisterID* emitBytecode(BytecodeGenerator&, RegisterID* = 0);
-
-        ExpressionNode* m_expr1;
-        ExpressionNode* m_expr2;
+        void append(ExpressionNode* expr) { m_expressions.append(expr); }
+
+    private:
+        virtual bool isCommaNode() const { return true; }
+        virtual RegisterID* emitBytecode(BytecodeGenerator&, RegisterID* = 0);
+
+        ExpressionVector m_expressions;
     };