Add DoubleToSmi optimistically, preventing boxing/unboxing of doubles and propagate smi-nessof the …

runtime/vm/intermediate_language.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.
 
 #include "vm/intermediate_language.h"
 
 #include "vm/bit_vector.h"
 #include "vm/dart_entry.h"
 #include "vm/flow_graph_allocator.h"
 #include "vm/flow_graph_builder.h"
@@ skipping 1438 matching lines @@
 RawAbstractType* SmiToDoubleInstr::CompileType() const {
   return Type::Double();
 }
 
 
 RawAbstractType* DoubleToIntegerInstr::CompileType() const {
   return Type::IntType();
 }
 
 
+RawAbstractType* DoubleToSmiInstr::CompileType() const {
+  return Type::SmiType();
+}
+
+
 RawAbstractType* CheckClassInstr::CompileType() const {
   return AbstractType::null();
 }
 
 
 RawAbstractType* CheckSmiInstr::CompileType() const {
   return AbstractType::null();
 }
 
 
@@ skipping 1294 matching lines @@
     default:
       UNREACHABLE();
       return -1;
   }
 }
 
 
 #undef __
 
 }  // namespace dart