Forward stores to loads for SIMD arrays

runtime/vm/flow_graph_optimizer.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/flow_graph_optimizer.h"
 
 #include "vm/bit_vector.h"
 #include "vm/cha.h"
 #include "vm/dart_entry.h"
 #include "vm/flow_graph_builder.h"
@@ skipping 4921 matching lines @@
           BitVector* killed = aliased_set_->Get(alias);
 
           if (killed != NULL) {
             kill->AddAll(killed);
             // There is no need to clear out_values when clearing GEN set
             // because only those values that are in the GEN set
             // will ever be used.
             gen->RemoveAll(killed);
           }
 
-          // Only forward stores to normal arrays and float64 arrays
+          // Only forward stores to normal arrays, float64, and simd arrays
           // to loads because other array stores (intXX/uintXX/float32)
           // may implicitly convert the value stored.
           StoreIndexedInstr* array_store = instr->AsStoreIndexed();
-          if (array_store == NULL ||
-              array_store->class_id() == kArrayCid ||
-              array_store->class_id() == kTypedDataFloat64ArrayCid) {
+          if ((array_store == NULL) ||
+              (array_store->class_id() == kArrayCid) ||
+              (array_store->class_id() == kTypedDataFloat64ArrayCid) ||
+              (array_store->class_id() == kTypedDataFloat32x4ArrayCid)) {
             bool is_load = false;
             Place store_place(instr, &is_load);
             ASSERT(!is_load);
             Place* place = map_->Lookup(&store_place);
             if (place != NULL) {
               // Store has a corresponding numbered place that might have a
               // load. Try forwarding stored value to it.
               gen->Add(place->id());
               if (out_values == NULL) out_values = CreateBlockOutValues();
               (*out_values)[place->id()] = GetStoredValue(instr);
@@ skipping 2808 matching lines @@
   }
 
   // Insert materializations at environment uses.
   for (intptr_t i = 0; i < exits.length(); i++) {
     CreateMaterializationAt(exits[i], alloc, alloc->cls(), *fields);
   }
 }
 
 
 }  // namespace dart