Strict mode delete.

src/arm/codegen-arm.cc

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 //
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@@ skipping 5826 matching lines @@
     // LoadCondition may (and usually does) leave a test and branch to
     // be emitted by the caller.  In that case, negate the condition.
     if (has_cc()) cc_reg_ = NegateCondition(cc_reg_);
 
   } else if (op == Token::DELETE) {
     Property* property = node->expression()->AsProperty();
     Variable* variable = node->expression()->AsVariableProxy()->AsVariable();
     if (property != NULL) {
       Load(property->obj());
       Load(property->key());
-      frame_->InvokeBuiltin(Builtins::DELETE, CALL_JS, 2);
+      frame_->EmitPush(Operand(Smi::FromInt(strict_mode_flag())));
+      frame_->InvokeBuiltin(Builtins::DELETE, CALL_JS, 3);
       frame_->EmitPush(r0);
 
     } else if (variable != NULL) {
+      ASSERT(strict_mode_flag() == kNonStrictMode);

[Martin Maly, 2011/02/14 05:15:22]

"delete foo" is disallowed in strict mode so we can only reach this code in
non-strict mode.

[Mads Ager (chromium), 2011/02/14 10:27:24]

And 'this' rewrites to a slot, right?

Also, could you put in your review comment here as a code comment to make it
clearer when reading this code later?

[Kevin Millikin (Chromium), 2011/02/14 11:56:55]

It just doesn't rewrite to a property reference (global variables don't have a
rewrite).

[Martin Maly, 2011/02/14 21:46:51]

Yes, this rewrites to a slot.
Added comment.

       Slot* slot = variable->AsSlot();
       if (variable->is_global()) {
         LoadGlobal();
         frame_->EmitPush(Operand(variable->name()));
-        frame_->InvokeBuiltin(Builtins::DELETE, CALL_JS, 2);
+        frame_->EmitPush(Operand(Smi::FromInt(kNonStrictMode)));
+        frame_->InvokeBuiltin(Builtins::DELETE, CALL_JS, 3);
         frame_->EmitPush(r0);
 
       } else if (slot != NULL && slot->type() == Slot::LOOKUP) {
         // Delete from the context holding the named variable.
         frame_->EmitPush(cp);
         frame_->EmitPush(Operand(variable->name()));
         frame_->CallRuntime(Runtime::kDeleteContextSlot, 2);
         frame_->EmitPush(r0);
 
       } else {
@@ skipping 1504 matching lines @@
                BinaryOpIC::GetName(runtime_operands_type_));
   return name_;
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM