Widen the type of constant values handled by constant propagation.

runtime/vm/flow_graph_optimizer.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/flow_graph_optimizer.h"
 
 #include "vm/bit_vector.h"
 #include "vm/cha.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/flow_graph_compiler.h"
@@ skipping 4509 matching lines @@
           }
         }
       }
     }
 
     for (ForwardInstructionIterator i(block); !i.Done(); i.Advance()) {
       Definition* defn = i.Current()->AsDefinition();
       // Replace constant-valued instructions without observable side
       // effects.  Do this for smis only to avoid having to copy other
       // objects into the heap's old generation.
-      //
-      // TODO(kmillikin): Extend this to handle booleans, other number
-      // types, etc.
       if ((defn != NULL) &&
-          (defn->constant_value().IsSmi() ||
-           defn->constant_value().IsNull() ||
-           defn->constant_value().IsTypeArguments()) &&
+          IsConstant(defn->constant_value()) &&
+          (defn->constant_value().IsSmi() || defn->constant_value().IsOld()) &&
           !defn->IsConstant() &&
           !defn->IsPushArgument() &&
           !defn->IsStoreIndexed() &&
           !defn->IsStoreInstanceField() &&
           !defn->IsStoreStaticField() &&
           !defn->IsStoreVMField()) {
         if (FLAG_trace_constant_propagation) {
           OS::Print("Constant v%"Pd" = %s\n",
                     defn->ssa_temp_index(),
                     defn->constant_value().ToCString());
@@ skipping 54 matching lines @@
 
   if (FLAG_trace_constant_propagation) {
     OS::Print("\n==== After constant propagation ====\n");
     FlowGraphPrinter printer(*graph_);
     printer.PrintBlocks();
   }
 }
 
 
 }  // namespace dart