Specialize mint shift code on arm for a constant shift amount.

runtime/vm/locations.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/locations.h"
 
 #include "vm/assembler.h"
 #include "vm/il_printer.h"
 #include "vm/intermediate_language.h"
 #include "vm/flow_graph_compiler.h"
@@ skipping 66 matching lines @@
 
 
 Location Location::RegisterOrSmiConstant(Value* value) {
   ConstantInstr* constant = value->definition()->AsConstant();
   return ((constant != NULL) && Assembler::IsSafeSmi(constant->value()))
       ? Location::Constant(constant->value())
       : Location::RequiresRegister();
 }
 
 
+Location Location::WritableRegisterOrSmiConstant(Value* value) {
+  ConstantInstr* constant = value->definition()->AsConstant();
+  return ((constant != NULL) && Assembler::IsSafeSmi(constant->value()))
+      ? Location::Constant(constant->value())
+      : Location::WritableRegister();
+}
+
+
 Location Location::FixedRegisterOrConstant(Value* value, Register reg) {
   ConstantInstr* constant = value->definition()->AsConstant();
   return ((constant != NULL) && Assembler::IsSafe(constant->value()))
       ? Location::Constant(constant->value())
       : Location::RegisterLocation(reg);
 }
 
 
 Location Location::FixedRegisterOrSmiConstant(Value* value, Register reg) {
   ConstantInstr* constant = value->definition()->AsConstant();
@@ skipping 141 matching lines @@
 
   if (!out(0).IsInvalid()) {
     f->Print(" => ");
     out(0).PrintTo(f);
   }
 
   if (always_calls()) f->Print(" C");
 }
 
 }  // namespace dart