VM: Array bounds checks that don't deoptimize for precompiled code.

runtime/vm/precompiler.cc

 // Copyright (c) 2015, 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/precompiler.h"
 
 #include "vm/aot_optimizer.h"
 #include "vm/assembler.h"
 #include "vm/ast_printer.h"
 #include "vm/branch_optimizer.h"
@@ skipping 2656 matching lines @@
               compiler_timeline,
               "AllocationSinking::DetachMaterializations");
 #endif  // !PRODUCT
           // Remove all MaterializeObject instructions inserted by allocation
           // sinking from the flow graph and let them float on the side
           // referenced only from environments. Register allocator will consider
           // them as part of a deoptimization environment.
           sinking->DetachMaterializations();
         }
 
+        // Replace bounds check instruction with a generic one.
+        optimizer.ReplaceArrayBoundChecks();
+
         // Compute and store graph informations (call & instruction counts)
         // to be later used by the inliner.
         FlowGraphInliner::CollectGraphInfo(flow_graph, true);
 
         {
 #ifndef PRODUCT
           TimelineDurationScope tds2(thread(),
                                      compiler_timeline,
                                      "AllocateRegisters");
 #endif  // !PRODUCT
@@ skipping 193 matching lines @@
       CompilationPipeline::New(thread->zone(), function);
 
   ASSERT(FLAG_precompiled_mode);
   const bool optimized = function.IsOptimizable();  // False for natives.
   return PrecompileFunctionHelper(pipeline, function, optimized);
 }
 
 #endif  // DART_PRECOMPILER
 
 }  // namespace dart