[es6] implement destructuring assignment

src/ast-numbering.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/ast-numbering.h"
 
 #include "src/ast.h"
 #include "src/scopes.h"
 
 namespace v8 {
@@ skipping 330 matching lines @@
 
 void AstNumberingVisitor::VisitProperty(Property* node) {
   VisitPropertyReference(node);
   ReserveFeedbackSlots(node);
 }
 
 
 void AstNumberingVisitor::VisitAssignment(Assignment* node) {
   IncrementNodeCount();
   node->set_base_id(ReserveIdRange(Assignment::num_ids()));
+
+  AssignmentPattern* pattern = node->target()->AsAssignmentPattern();
+  if (pattern && pattern->is_rewritten()) {
+    return Visit(pattern->expression());
+  }
+
   if (node->is_compound()) VisitBinaryOperation(node->binary_operation());
   VisitReference(node->target());
   Visit(node->value());
   ReserveFeedbackSlots(node);
 }
 
 
 void AstNumberingVisitor::VisitBinaryOperation(BinaryOperation* node) {
   IncrementNodeCount();
   node->set_base_id(ReserveIdRange(BinaryOperation::num_ids()));
@@ skipping 105 matching lines @@
   if (node->class_variable_proxy()) {
     VisitVariableProxy(node->class_variable_proxy());
   }
   for (int i = 0; i < node->properties()->length(); i++) {
     VisitObjectLiteralProperty(node->properties()->at(i));
   }
   ReserveFeedbackSlots(node);
 }
 
 
+void AstNumberingVisitor::VisitAssignmentPattern(AssignmentPattern* node) {
+  IncrementNodeCount();
+  Visit(node->expression());
+}
+
+
 void AstNumberingVisitor::VisitObjectLiteral(ObjectLiteral* node) {
   IncrementNodeCount();
   node->set_base_id(ReserveIdRange(node->num_ids()));
   for (int i = 0; i < node->properties()->length(); i++) {
     VisitObjectLiteralProperty(node->properties()->at(i));
   }
   node->BuildConstantProperties(isolate_);
   // Mark all computed expressions that are bound to a key that
   // is shadowed by a later occurrence of the same key. For the
   // marked expressions, no store code will be is emitted.
@@ skipping 97 matching lines @@
 }
 
 
 bool AstNumbering::Renumber(Isolate* isolate, Zone* zone,
                             FunctionLiteral* function) {
   AstNumberingVisitor visitor(isolate, zone);
   return visitor.Renumber(function);
 }
 }  // namespace internal
 }  // namespace v8