Fix polymorphic inlining of method dispatchers.

runtime/vm/flow_graph_inliner.cc

Index: runtime/vm/flow_graph_inliner.cc
===================================================================
--- runtime/vm/flow_graph_inliner.cc	(revision 34963)
+++ runtime/vm/flow_graph_inliner.cc	(working copy)
@@ -302,7 +302,7 @@
               current->AsPolymorphicInstanceCall();
           if (!inline_only_recognized_methods ||
               instance_call->HasSingleRecognizedTarget() ||
-              instance_call->HasSingleDispatcherTarget()) {
+              instance_call->HasOnlyDispatcherTargets()) {

[Ivan Posva, 2014/04/11 21:12:01]

This is not correct. Only checking for dispatcher targets is too permissive.

[Florian Schneider, 2014/04/22 00:09:10]

Permissive for what?

[Ivan Posva, 2014/04/24 07:28:47]

There is not necessarily only a single recognized target only because this
instance call has only dispatcher targets.

[Florian Schneider, 2014/04/24 12:00:44]

There is no correctness requirement that the call site has a single recognized
target. This condition could be widened to multiple recognized targets.

The condition is here to inline recognized targets when we at the deepest
allowed inlining depth.

I added the case that dispatchers are always inlined at the max inlining depth.

             instance_calls_.Add(InstanceCallInfo(instance_call, graph));
           } else {
             // Method not inlined because inlining too deep and method
@@ -961,7 +961,7 @@
       ASSERT(call->ArgumentCount() > 0);
       Function& target = Function::ZoneHandle();
       AllocateObjectInstr* alloc =
-          call->ArgumentAt(0)->AsAllocateObject();
+          call->ArgumentAt(0)->OriginalDefinition()->AsAllocateObject();
       if ((alloc != NULL) && !alloc->closure_function().IsNull()) {
         target ^= alloc->closure_function().raw();
         ASSERT(target.signature_class() == alloc->cls().raw());