Clean up handling of guarded fields in the flow graph builder.

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/longjump.h"
@@ skipping 20 matching lines @@
     num_stack_locals_(builder.num_stack_locals()),
     graph_entry_(graph_entry),
     preorder_(),
     postorder_(),
     reverse_postorder_(),
     optimized_block_order_(),
     block_effects_(NULL),
     licm_allowed_(true),
     use_far_branches_(false),
     loop_headers_(NULL),
-    loop_invariant_loads_(NULL) {
+    loop_invariant_loads_(NULL),
+    guarded_fields_(builder.guarded_fields()) {
   DiscoverBlocks();
 }
 
 
+void FlowGraph::AddToGuardedFields(
+    const Field* field,
+    ZoneGrowableArray<const Field*>* array) {
+  if ((field->guarded_cid() == kDynamicCid) ||
+      (field->guarded_cid() == kIllegalCid)) {
+    return;
+  }
+  for (intptr_t j = 0; j < array->length(); j++) {
+    if ((*array)[j]->raw() == field->raw()) {
+      return;
+    }
+  }
+  array->Add(field);
+}
+
+
 GrowableArray<BlockEntryInstr*>* FlowGraph::codegen_block_order(
     bool is_optimized) {
   return (is_optimized && FLAG_reorder_basic_blocks)
       ? &optimized_block_order_
       : &reverse_postorder_;
 }
 
 
 ConstantInstr* FlowGraph::GetConstant(const Object& object) {
   // Check if the constant is already in the pool.
@@ skipping 1113 matching lines @@
 }
 
 
 bool BlockEffects::IsSideEffectFreePath(BlockEntryInstr* from,
                                         BlockEntryInstr* to) const {
   return available_at_[to->postorder_number()]->Contains(
       from->postorder_number());
 }
 
 }  // namespace dart