Replace tagged keys for fast access by smi, and use smi in boundscheck.

src/code-stubs-hydrogen.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 400 matching lines @@
 Handle<Code> FastCloneShallowObjectStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 
 template <>
 HValue* CodeStubGraphBuilder<KeyedLoadFastElementStub>::BuildCodeStub() {
   HInstruction* load = BuildUncheckedMonomorphicElementAccess(
       GetParameter(0), GetParameter(1), NULL, NULL,
       casted_stub()->is_js_array(), casted_stub()->elements_kind(),
-      false, NEVER_RETURN_HOLE, STANDARD_STORE, Representation::Tagged());
+      false, NEVER_RETURN_HOLE, STANDARD_STORE, Representation::Smi());
   return load;
 }
 
 
 Handle<Code> KeyedLoadFastElementStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 
 template<>
@@ skipping 25 matching lines @@
   return DoGenerateCode(this);
 }
 
 
 template <>
 HValue* CodeStubGraphBuilder<KeyedStoreFastElementStub>::BuildCodeStub() {
   BuildUncheckedMonomorphicElementAccess(
       GetParameter(0), GetParameter(1), GetParameter(2), NULL,
       casted_stub()->is_js_array(), casted_stub()->elements_kind(),
       true, NEVER_RETURN_HOLE, casted_stub()->store_mode(),
-      Representation::Tagged());
+      Representation::Smi());
 
   return GetParameter(2);
 }
 
 
 Handle<Code> KeyedStoreFastElementStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 
@@ skipping 103 matching lines @@
 
   HConstant* max_alloc_length =
       new(zone()) HConstant(JSObject::kInitialMaxFastElementArray,
                             Representation::Tagged());
   AddInstruction(max_alloc_length);
   const int initial_capacity = JSArray::kPreallocatedArrayElements;
   HConstant* initial_capacity_node =
       new(zone()) HConstant(initial_capacity, Representation::Tagged());
   AddInstruction(initial_capacity_node);
 
   // Since we're forcing Integer32 representation for this HBoundsCheck,

[Jakob Kummerow, 2013/05/24 08:41:16]

This comment seems outdated. I think you can just remove it.

   // there's no need to Smi-check the index.
   HBoundsCheck* checked_arg = AddBoundsCheck(argument, max_alloc_length,
                                              ALLOW_SMI_KEY,
-                                             Representation::Tagged());
+                                             Representation::Smi());
   IfBuilder if_builder(this);
   if_builder.IfCompare(checked_arg, constant_zero, Token::EQ);
   if_builder.Then();
   Push(initial_capacity_node);  // capacity
   Push(constant_zero);  // length
   if_builder.Else();
   Push(checked_arg);  // capacity
   Push(checked_arg);  // length
   if_builder.End();
 
@@ skipping 88 matching lines @@
       ? graph()->GetConstantSmi1()
       : graph()->GetConstantUndefined();
 }
 
 
 Handle<Code> CompareNilICStub::GenerateCode() {
   return DoGenerateCode(this);
 }
 
 } }  // namespace v8::internal