Ensure that compile time types for comparisons are recomputed once comparison are specialized.

runtime/vm/intermediate_language_x64.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/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/intermediate_language.h"
 
 #include "lib/error.h"
@@ skipping 941 matching lines @@
   Register result = locs()->out().reg();
   __ movq(result,
           Immediate(reinterpret_cast<uword>(Symbols::PredefinedAddress())));
   __ movq(result, Address(result,
                           char_code,
                           TIMES_HALF_WORD_SIZE,  // Char code is a smi.
                           Symbols::kNullCharCodeSymbolOffset * kWordSize));
 }
 
 
-CompileType* LoadIndexedInstr::ComputeInitialType() const {
+CompileType LoadIndexedInstr::ComputeType() const {
   switch (class_id_) {
     case kArrayCid:
     case kImmutableArrayCid:
       return CompileType::Dynamic();
 
     case kFloat32ArrayCid :
     case kFloat64ArrayCid :
       return CompileType::FromCid(kDoubleCid);
 
     case kInt8ArrayCid:
     case kUint8ArrayCid:
     case kUint8ClampedArrayCid:
     case kExternalUint8ArrayCid:
     case kExternalUint8ClampedArrayCid:
     case kInt16ArrayCid:
     case kUint16ArrayCid:
     case kOneByteStringCid:
     case kTwoByteStringCid:
     case kInt32ArrayCid:
     case kUint32ArrayCid:
       return CompileType::FromCid(kSmiCid);
 
     default:
       UNIMPLEMENTED();
-      return NULL;
+      return CompileType::Dynamic();
   }
 }
 
 
 Representation LoadIndexedInstr::representation() const {
   switch (class_id_) {
     case kArrayCid:
     case kImmutableArrayCid:
     case kInt8ArrayCid:
     case kUint8ArrayCid:
@@ skipping 2110 matching lines @@
                          PcDescriptors::kOther,
                          locs());
   __ Drop(2);  // Discard type arguments and receiver.
 }
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_X64