VM: Avoid repeated deoptimizations from hoisted array bounds checks.

runtime/vm/intermediate_language_arm64.cc

 // Copyright (c) 2014, 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/globals.h"  // Needed here to get TARGET_ARCH_ARM64.
 #if defined(TARGET_ARCH_ARM64)
 
 #include "vm/intermediate_language.h"
 
 #include "vm/dart_entry.h"
@@ skipping 5114 matching lines @@
   const intptr_t kNumTemps = 0;
   LocationSummary* locs = new(isolate) LocationSummary(
       isolate, kNumInputs, kNumTemps, LocationSummary::kNoCall);
   locs->set_in(kLengthPos, Location::RegisterOrSmiConstant(length()));
   locs->set_in(kIndexPos, Location::RegisterOrSmiConstant(index()));
   return locs;
 }
 
 
 void CheckArrayBoundInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
+  uint32_t flags = generalized_ ? ICData::kGeneralized : 0;
+  flags |= licm_hoisted_ ? ICData::kHoisted : 0;
   Label* deopt = compiler->AddDeoptStub(
       deopt_id(),
       ICData::kDeoptCheckArrayBound,
-      generalized_ ? ICData::kGeneralized : 0);
+      flags);
 
   Location length_loc = locs()->in(kLengthPos);
   Location index_loc = locs()->in(kIndexPos);
 
   if (length_loc.IsConstant() && index_loc.IsConstant()) {
     // TODO(srdjan): remove this code once failures are fixed.
     if ((Smi::Cast(length_loc.constant()).Value() >
          Smi::Cast(index_loc.constant()).Value()) &&
         (Smi::Cast(index_loc.constant()).Value() >= 0)) {
       // This CheckArrayBoundInstr should have been eliminated.
@@ skipping 455 matching lines @@
   compiler->GenerateCall(token_pos(), &label, stub_kind_, locs());
 #if defined(DEBUG)
   __ LoadImmediate(R4, kInvalidObjectPointer, kNoPP);
   __ LoadImmediate(R5, kInvalidObjectPointer, kNoPP);
 #endif
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM64