Make invalid LHSs a parse-time (reference) error

src/x64/full-codegen-x64.cc

Index: src/x64/full-codegen-x64.cc
diff --git a/src/x64/full-codegen-x64.cc b/src/x64/full-codegen-x64.cc
index b146809a24e19a745a5d3810b97ad4bcff8412d9..9739e556e4c4411a3148853ec9e7aad7510d77b0 100644
--- a/src/x64/full-codegen-x64.cc
+++ b/src/x64/full-codegen-x64.cc
@@ -1836,13 +1836,9 @@ void FullCodeGenerator::VisitArrayLiteral(ArrayLiteral* expr) {
 
 
 void FullCodeGenerator::VisitAssignment(Assignment* expr) {
+  ASSERT(expr->target()->IsValidLeftHandSide());
+
   Comment cmnt(masm_, "[ Assignment");
-  // Invalid left-hand sides are rewritten to have a 'throw ReferenceError'
-  // on the left-hand side.
-  if (!expr->target()->IsValidLeftHandSide()) {
-    VisitForEffect(expr->target());
-    return;
-  }
 
   // Left-hand side can only be a property, a global or a (parameter or local)
   // slot.
@@ -2339,12 +2335,7 @@ void FullCodeGenerator::EmitBinaryOp(BinaryOperation* expr,
 
 
 void FullCodeGenerator::EmitAssignment(Expression* expr) {
-  // Invalid left-hand sides are rewritten by the parser to have a 'throw
-  // ReferenceError' on the left-hand side.
-  if (!expr->IsValidLeftHandSide()) {
-    VisitForEffect(expr);
-    return;
-  }
+  ASSERT(expr->IsValidLeftHandSide());
 
   // Left-hand side can only be a property, a global or a (parameter or local)
   // slot.
@@ -4270,16 +4261,11 @@ void FullCodeGenerator::VisitUnaryOperation(UnaryOperation* expr) {
 
 
 void FullCodeGenerator::VisitCountOperation(CountOperation* expr) {
+  ASSERT(expr->expression()->IsValidLeftHandSide());
+
   Comment cmnt(masm_, "[ CountOperation");
   SetSourcePosition(expr->position());
 
-  // Invalid left-hand-sides are rewritten to have a 'throw
-  // ReferenceError' as the left-hand side.
-  if (!expr->expression()->IsValidLeftHandSide()) {
-    VisitForEffect(expr->expression());
-    return;
-  }
-
   // Expression can only be a property, a global or a (parameter or local)
   // slot.
   enum LhsKind { VARIABLE, NAMED_PROPERTY, KEYED_PROPERTY };