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

runtime/vm/intrinsifier.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.
 // Class for intrinsifying functions.
 
 #include "vm/assembler.h"
 #include "vm/compiler.h"
 #include "vm/cpu.h"
 #include "vm/flags.h"
 #include "vm/flow_graph.h"
@@ skipping 355 matching lines @@
   FlowGraph* flow_graph_;
   BlockEntryInstr* entry_;
   Instruction* current_;
 };
 
 
 static void PrepareIndexedOp(BlockBuilder* builder,
                              Definition* array,
                              Definition* index,
                              intptr_t length_offset) {
-  TokenPosition token_pos = builder->TokenPos();
-  builder->AddInstruction(
-      new CheckSmiInstr(new Value(index),
-                        Thread::kNoDeoptId,
-                        token_pos));
-
   Definition* length = builder->AddDefinition(
       new LoadFieldInstr(new Value(array),
                          length_offset,
                          Type::ZoneHandle(Type::SmiType()),
                          TokenPosition::kNoSource));
   builder->AddInstruction(
       new CheckArrayBoundInstr(new Value(length),
                                new Value(index),
                                Thread::kNoDeoptId));
 }
@@ skipping 841 matching lines @@
   TargetEntryInstr* normal_entry = graph_entry->normal_entry();
   BlockBuilder builder(flow_graph, normal_entry);
 
   return BuildInvokeMathCFunction(&builder,
                                   MethodRecognizer::kDoubleRound);
 }
 #endif  // !defined(TARGET_ARCH_DBC)
 
 
 }  // namespace dart