Allows turning on checked mode on a per-isolate basis

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/cpu.h"
 #include "vm/dart_entry.h"
@@ skipping 1181 matching lines @@
   ASSERT(array_cid != kIllegalCid);
 
   Definition* array = receiver;
   Definition* index = call->ArgumentAt(1);
   Definition* stored_value = call->ArgumentAt(2);
 
   *entry = new(Z) TargetEntryInstr(flow_graph()->allocate_block_id(),
                                    call->GetBlock()->try_index());
   (*entry)->InheritDeoptTarget(I, call);
   Instruction* cursor = *entry;
-  if (FLAG_enable_type_checks) {
+  if (I->TypeChecksEnabled()) {
     // Only type check for the value. A type check for the index is not
     // needed here because we insert a deoptimizing smi-check for the case
     // the index is not a smi.
     const AbstractType& value_type =
         AbstractType::ZoneHandle(Z, target.ParameterTypeAt(2));
     Definition* instantiator = NULL;
     Definition* type_args = NULL;
     switch (array_cid) {
       case kArrayCid:
       case kGrowableObjectArrayCid: {
@@ skipping 3278 matching lines @@
   if (!instr->can_pack_into_smi())
     instr->set_representation(kUnboxedMint);
 #endif
 }
 
 
 bool FlowGraphOptimizer::TryInlineInstanceSetter(InstanceCallInstr* instr,
                                                  const ICData& unary_ic_data) {
   ASSERT((unary_ic_data.NumberOfChecks() > 0) &&
       (unary_ic_data.NumArgsTested() == 1));
-  if (FLAG_enable_type_checks) {
+  if (I->TypeChecksEnabled()) {
     // Checked mode setters are inlined like normal methods by conventional
     // inlining.
     return false;
   }
 
   ASSERT(instr->HasICData());
   if (unary_ic_data.NumberOfChecks() == 0) {
     // No type feedback collected.
     return false;
   }
@@ skipping 4096 matching lines @@
 
   // Insert materializations at environment uses.
   for (intptr_t i = 0; i < exits_collector_.exits().length(); i++) {
     CreateMaterializationAt(
         exits_collector_.exits()[i], alloc, *slots);
   }
 }
 
 
 }  // namespace dart