When attempting to to inline a field getter we use the incoming cid. That type may differ between v…

runtime/vm/flow_graph_optimizer.cc

Index: runtime/vm/flow_graph_optimizer.cc
===================================================================
--- runtime/vm/flow_graph_optimizer.cc	(revision 20492)
+++ runtime/vm/flow_graph_optimizer.cc	(working copy)
@@ -87,10 +87,17 @@
   ASSERT(call->ic_data()->num_args_tested() <= call->ArgumentCount());
   for (intptr_t i = 0; i < call->ic_data()->num_args_tested(); i++) {
     intptr_t cid = call->PushArgumentAt(i)->value()->Type()->ToCid();
+    if (cid == kDynamicCid) {

[Vyacheslav Egorov (Google), 2013/03/26 18:56:13]

How about a bit different approach:

In Definition::ReplaceUsesWith(Definition* other) when iterating over input uses
we can check if current->Type() == this->Type() and if this is the case reset
current->type_ to NULL.

To avoid doing unnecessary updates we can have bool argument to
ReplaceUsesWith/ReplaceWith that controls whether or not we update types.

And in the FlowGraphOptimizer we can have a member that says update_types_ that
is true when we are in the ApplyClassIds.

In this case we will keep types more up to date, and will need to have any
special casing here.

[srdjan, 2013/03/26 20:34:52]

Yes, update the type in ReplaceUsesWith. In order to implement simple code, I
decided to always set reaching type to NULL. Did not measure negative impact on
compilation speed of dart2js.

+      // Definition's type may differ from value's type as it may have been
+      // changed by guarded_cid of an inlined LoadField.
+      cid = call->PushArgumentAt(i)->value()->definition()->Type()->ToCid();
+    }
     class_ids.Add(cid);
   }
-  // TODO(srdjan): Test for other class_ids > 1.
-  if (class_ids.length() != 1) return false;
+  // TODO(srdjan): Test for number of arguments checked greater than 1.
+  if (class_ids.length() != 1) {
+    return false;
+  }
   if (class_ids[0] != kDynamicCid) {
     const intptr_t num_named_arguments = call->argument_names().IsNull() ?
         0 : call->argument_names().Length();