Recognize pattern (a << b) & c with c being a positive Smi and allow left shift to truncate the res…

runtime/vm/il_printer.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/il_printer.h"
 
 #include "vm/intermediate_language.h"
 #include "vm/os.h"
 #include "vm/parser.h"
 
@@ skipping 499 matching lines @@
 void CatchEntryInstr::PrintOperandsTo(BufferFormatter* f) const {
   f->Print("%s, %s",
            exception_var().name().ToCString(),
            stacktrace_var().name().ToCString());
 }
 
 
 void BinarySmiOpInstr::PrintTo(BufferFormatter* f) const {
   Definition::PrintTo(f);
   f->Print(" %co", overflow_ ? '+' : '-');
+  f->Print(" %ct", is_truncating() ? '+' : '-');
 }
 
+
 void BinarySmiOpInstr::PrintOperandsTo(BufferFormatter* f) const {
   f->Print("%s, ", Token::Str(op_kind()));
   left()->PrintTo(f);
   f->Print(", ");
   right()->PrintTo(f);
 }
 
 
 void BinaryDoubleOpInstr::PrintOperandsTo(BufferFormatter* f) const {
   f->Print("%s, ", Token::Str(op_kind()));
@@ skipping 173 matching lines @@
       f->Print(" [");
       locations_[i].PrintTo(f);
       f->Print("]");
     }
   }
   f->Print(" }");
   if (outer_ != NULL) outer_->PrintTo(f);
 }
 
 }  // namespace dart