Use mutable heapnumbers to store doubles in fields.

src/stub-cache.cc

Index: src/stub-cache.cc
diff --git a/src/stub-cache.cc b/src/stub-cache.cc
index 214527f09c17fced40202ed429c144b6e04be03e..5bfa03cf9d2c8075273affcc1015785bb43b9c7f 100644
--- a/src/stub-cache.cc
+++ b/src/stub-cache.cc
@@ -221,10 +221,12 @@ Handle<Code> StubCache::ComputeLoadNonexistent(Handle<Name> name,
 Handle<Code> StubCache::ComputeLoadField(Handle<Name> name,
                                          Handle<JSObject> receiver,
                                          Handle<JSObject> holder,
-                                         PropertyIndex field) {
+                                         PropertyIndex field,
+                                         Representation representation) {
   if (receiver.is_identical_to(holder)) {
     LoadFieldStub stub(field.is_inobject(holder),
-                       field.translate(holder));
+                       field.translate(holder),
+                       representation);
     return stub.GetCode(isolate());
   }
 
@@ -235,7 +237,7 @@ Handle<Code> StubCache::ComputeLoadField(Handle<Name> name,
 
   LoadStubCompiler compiler(isolate_);
   Handle<Code> handler =
-      compiler.CompileLoadField(receiver, holder, name, field);
+      compiler.CompileLoadField(receiver, holder, name, field, representation);
   JSObject::UpdateMapCodeCache(stub_holder, name, handler);
   return handler;
 }
@@ -336,10 +338,12 @@ Handle<Code> StubCache::ComputeLoadGlobal(Handle<Name> name,
 Handle<Code> StubCache::ComputeKeyedLoadField(Handle<Name> name,
                                               Handle<JSObject> receiver,
                                               Handle<JSObject> holder,
-                                              PropertyIndex field) {
+                                              PropertyIndex field,
+                                              Representation representation) {
   if (receiver.is_identical_to(holder)) {
     KeyedLoadFieldStub stub(field.is_inobject(holder),
-                            field.translate(holder));
+                            field.translate(holder),
+                            representation);
     return stub.GetCode(isolate());
   }
 
@@ -350,7 +354,7 @@ Handle<Code> StubCache::ComputeKeyedLoadField(Handle<Name> name,
 
   KeyedLoadStubCompiler compiler(isolate_);
   Handle<Code> handler =
-      compiler.CompileLoadField(receiver, holder, name, field);
+      compiler.CompileLoadField(receiver, holder, name, field, representation);
   JSObject::UpdateMapCodeCache(stub_holder, name, handler);
   return handler;
 }
@@ -1494,15 +1498,17 @@ Register BaseLoadStubCompiler::HandlerFrontend(Handle<JSObject> object,
 }
 
 
-Handle<Code> BaseLoadStubCompiler::CompileLoadField(Handle<JSObject> object,
-                                                    Handle<JSObject> holder,
-                                                    Handle<Name> name,
-                                                    PropertyIndex field) {
+Handle<Code> BaseLoadStubCompiler::CompileLoadField(
+    Handle<JSObject> object,
+    Handle<JSObject> holder,
+    Handle<Name> name,
+    PropertyIndex field,
+    Representation representation) {
   Label miss;
 
   Register reg = HandlerFrontendHeader(object, receiver(), holder, name, &miss);
 
-  GenerateLoadField(reg, holder, field);
+  GenerateLoadField(reg, holder, field, representation);
 
   __ bind(&miss);
   TailCallBuiltin(masm(), MissBuiltin(kind()));
@@ -1512,19 +1518,6 @@ Handle<Code> BaseLoadStubCompiler::CompileLoadField(Handle<JSObject> object,
 }
 
 
-// Load a fast property out of a holder object (src). In-object properties
-// are loaded directly otherwise the property is loaded from the properties
-// fixed array.
-void StubCompiler::GenerateFastPropertyLoad(MacroAssembler* masm,
-                                            Register dst,
-                                            Register src,
-                                            Handle<JSObject> holder,
-                                            PropertyIndex index) {
-  DoGenerateFastPropertyLoad(
-      masm, dst, src, index.is_inobject(holder), index.translate(holder));
-}
-
-
 Handle<Code> BaseLoadStubCompiler::CompileLoadConstant(
     Handle<JSObject> object,
     Handle<JSObject> holder,
@@ -1587,14 +1580,16 @@ void BaseLoadStubCompiler::GenerateLoadPostInterceptor(
   if (lookup->IsField()) {
     PropertyIndex field = lookup->GetFieldIndex();
     if (interceptor_holder.is_identical_to(holder)) {
-      GenerateLoadField(interceptor_reg, holder, field);
+      GenerateLoadField(
+          interceptor_reg, holder, field, lookup->representation());
     } else {
       // We found FIELD property in prototype chain of interceptor's holder.
       // Retrieve a field from field's holder.
       Register reg = HandlerFrontend(
           interceptor_holder, interceptor_reg, holder, name, &success);
       __ bind(&success);
-      GenerateLoadField(reg, holder, field);
+      GenerateLoadField(
+          reg, holder, field, lookup->representation());
     }
   } else {
     // We found CALLBACKS property in prototype chain of interceptor's
@@ -1646,7 +1641,7 @@ Handle<Code> BaseStoreStubCompiler::CompileStoreTransition(
     LookupResult* lookup,
     Handle<Map> transition,
     Handle<Name> name) {
-  Label miss, miss_restore_name;
+  Label miss, miss_restore_name, slow;
 
   GenerateNameCheck(name, this->name(), &miss);
 
@@ -1658,13 +1653,17 @@ Handle<Code> BaseStoreStubCompiler::CompileStoreTransition(
                           receiver(), this->name(), value(),
                           scratch1(), scratch2(),
                           &miss,
-                          &miss_restore_name);
+                          &miss_restore_name,
+                          &slow);
 
   // Handle store cache miss.
   GenerateRestoreName(masm(), &miss_restore_name, name);
   __ bind(&miss);
   TailCallBuiltin(masm(), MissBuiltin(kind()));
 
+  GenerateRestoreName(masm(), &slow, name);
+  TailCallBuiltin(masm(), SlowBuiltin(kind()));
+
   // Return the generated code.
   return GetICCode(kind(), Code::MAP_TRANSITION, name);
 }