Fix bug with captured parameters and optimized try-catch.

runtime/vm/flow_graph.cc

 // Copyright (c) 2012, 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.h"
 
 #include "vm/bit_vector.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/intermediate_language.h"
 #include "vm/growable_array.h"
@@ skipping 23 matching lines @@
     postorder_(),
     reverse_postorder_(),
     optimized_block_order_(),
     constant_null_(NULL),
     constant_dead_(NULL),
     block_effects_(NULL),
     licm_allowed_(true),
     loop_headers_(NULL),
     loop_invariant_loads_(NULL),
     guarded_fields_(builder.guarded_fields()),
-    deferred_prefixes_(builder.deferred_prefixes()) {
+    deferred_prefixes_(builder.deferred_prefixes()),
+    captured_parameters_(
+        new(isolate_) BitVector(isolate_, variable_count())) {
   DiscoverBlocks();
 }
 
 
 void FlowGraph::AddToGuardedFields(
     ZoneGrowableArray<const Field*>* array,
     const Field* field) {
   if ((field->guarded_cid() == kDynamicCid) ||
       (field->guarded_cid() == kIllegalCid)) {
     return;
@@ skipping 897 matching lines @@
 
           PhiInstr* phi = result->AsPhi();
           if ((phi != NULL) && !phi->is_alive()) {
             phi->mark_alive();
             live_phis->Add(phi);
           }
 
           if (variable_liveness->IsLastLoad(block_entry, load)) {
             (*env)[index] = constant_dead();
           }
+
+          // Record captured parameters so that they can be skipped when
+          // emitting sync code inside optimized try-blocks.
+          if (load->local().is_captured_parameter()) {
+            intptr_t index = load->local().BitIndexIn(num_non_copied_params_);
+            captured_parameters_->Add(index);
+          }
+
         } else if (push != NULL) {
           result = push->value()->definition();
           env->Add(result);
           it.RemoveCurrentFromGraph();
           continue;
         } else if (drop != NULL) {
           // Drop temps from the environment.
           for (intptr_t j = 0; j < drop->num_temps(); j++) {
             env->RemoveLast();
           }
@@ skipping 326 matching lines @@
 }
 
 
 bool BlockEffects::IsSideEffectFreePath(BlockEntryInstr* from,
                                         BlockEntryInstr* to) const {
   return available_at_[to->postorder_number()]->Contains(
       from->postorder_number());
 }
 
 }  // namespace dart