diff --git a/src/ic/x87/access-compiler-x87.cc b/src/ic/x87/access-compiler-x87.cc
index 2c1b942..e528de6 100644
--- a/src/ic/x87/access-compiler-x87.cc
+++ b/src/ic/x87/access-compiler-x87.cc
@@ -18,19 +18,19 @@
 
 
 Register* PropertyAccessCompiler::load_calling_convention() {
-  // receiver, name, scratch1, scratch2, scratch3, scratch4.
+  // receiver, name, scratch1, scratch2, scratch3.
   Register receiver = LoadDescriptor::ReceiverRegister();
   Register name = LoadDescriptor::NameRegister();
-  static Register registers[] = {receiver, name, ebx, eax, edi, no_reg};
+  static Register registers[] = {receiver, name, ebx, eax, edi};
   return registers;
 }
 
 
 Register* PropertyAccessCompiler::store_calling_convention() {
-  // receiver, name, scratch1, scratch2, scratch3.
+  // receiver, name, scratch1, scratch2.
   Register receiver = StoreDescriptor::ReceiverRegister();
   Register name = StoreDescriptor::NameRegister();
-  static Register registers[] = {receiver, name, ebx, edi, no_reg};
+  static Register registers[] = {receiver, name, ebx, edi};
   return registers;
 }
 
diff --git a/src/ic/x87/handler-compiler-x87.cc b/src/ic/x87/handler-compiler-x87.cc
index 7983273..c5f2d9f 100644
--- a/src/ic/x87/handler-compiler-x87.cc
+++ b/src/ic/x87/handler-compiler-x87.cc
@@ -199,7 +199,7 @@
   Handle<CallHandlerInfo> api_call_info = optimization.api_call_info();
   bool call_data_undefined = false;
   // Put call data in place.
-  if (api_call_info->data()->IsUndefined()) {
+  if (api_call_info->data()->IsUndefined(isolate)) {
     call_data_undefined = true;
     __ mov(data, Immediate(isolate->factory()->undefined_value()));
   } else {
@@ -237,12 +237,12 @@
     MacroAssembler* masm, Handle<JSGlobalObject> global, Handle<Name> name,
     Register scratch, Label* miss) {
   Handle<PropertyCell> cell = JSGlobalObject::EnsurePropertyCell(global, name);
-  DCHECK(cell->value()->IsTheHole());
-  Factory* factory = masm->isolate()->factory();
-  Handle<WeakCell> weak_cell = factory->NewWeakCell(cell);
+  Isolate* isolate = masm->isolate();
+  DCHECK(cell->value()->IsTheHole(isolate));
+  Handle<WeakCell> weak_cell = isolate->factory()->NewWeakCell(cell);
   __ LoadWeakValue(scratch, weak_cell, miss);
   __ cmp(FieldOperand(scratch, PropertyCell::kValueOffset),
-         Immediate(factory->the_hole_value()));
+         Immediate(isolate->factory()->the_hole_value()));
   __ j(not_equal, miss);
 }
 
@@ -439,28 +439,25 @@
   DCHECK(!scratch2.is(object_reg) && !scratch2.is(holder_reg) &&
          !scratch2.is(scratch1));
 
-  if (FLAG_eliminate_prototype_chain_checks) {
-    Handle<Cell> validity_cell =
-        Map::GetOrCreatePrototypeChainValidityCell(receiver_map, isolate());
-    if (!validity_cell.is_null()) {
-      DCHECK_EQ(Smi::FromInt(Map::kPrototypeChainValid),
-                validity_cell->value());
-      // Operand::ForCell(...) points to the cell's payload!
-      __ cmp(Operand::ForCell(validity_cell),
-             Immediate(Smi::FromInt(Map::kPrototypeChainValid)));
-      __ j(not_equal, miss);
-    }
+  Handle<Cell> validity_cell =
+      Map::GetOrCreatePrototypeChainValidityCell(receiver_map, isolate());
+  if (!validity_cell.is_null()) {
+    DCHECK_EQ(Smi::FromInt(Map::kPrototypeChainValid), validity_cell->value());
+    // Operand::ForCell(...) points to the cell's payload!
+    __ cmp(Operand::ForCell(validity_cell),
+           Immediate(Smi::FromInt(Map::kPrototypeChainValid)));
+    __ j(not_equal, miss);
+  }
 
-    // The prototype chain of primitives (and their JSValue wrappers) depends
-    // on the native context, which can't be guarded by validity cells.
-    // |object_reg| holds the native context specific prototype in this case;
-    // we need to check its map.
-    if (check == CHECK_ALL_MAPS) {
-      __ mov(scratch1, FieldOperand(object_reg, HeapObject::kMapOffset));
-      Handle<WeakCell> cell = Map::WeakCellForMap(receiver_map);
-      __ CmpWeakValue(scratch1, cell, scratch2);
-      __ j(not_equal, miss);
-    }
+  // The prototype chain of primitives (and their JSValue wrappers) depends
+  // on the native context, which can't be guarded by validity cells.
+  // |object_reg| holds the native context specific prototype in this case;
+  // we need to check its map.
+  if (check == CHECK_ALL_MAPS) {
+    __ mov(scratch1, FieldOperand(object_reg, HeapObject::kMapOffset));
+    Handle<WeakCell> cell = Map::WeakCellForMap(receiver_map);
+    __ CmpWeakValue(scratch1, cell, scratch2);
+    __ j(not_equal, miss);
   }
 
   // Keep track of the current object in register reg.
@@ -496,8 +493,10 @@
            !current_map->is_access_check_needed());
 
     prototype = handle(JSObject::cast(current_map->prototype()));
-    if (current_map->is_dictionary_map() &&
-        !current_map->IsJSGlobalObjectMap()) {
+    if (current_map->IsJSGlobalObjectMap()) {
+      GenerateCheckPropertyCell(masm(), Handle<JSGlobalObject>::cast(current),
+                                name, scratch2, miss);
+    } else if (current_map->is_dictionary_map()) {
       DCHECK(!current_map->IsJSGlobalProxyMap());  // Proxy maps are fast.
       if (!name->IsUniqueName()) {
         DCHECK(name->IsString());
@@ -507,34 +506,12 @@
              current->property_dictionary()->FindEntry(name) ==
                  NameDictionary::kNotFound);
 
-      if (FLAG_eliminate_prototype_chain_checks && depth > 1) {
+      if (depth > 1) {
         // TODO(jkummerow): Cache and re-use weak cell.
         __ LoadWeakValue(reg, isolate()->factory()->NewWeakCell(current), miss);
       }
       GenerateDictionaryNegativeLookup(masm(), miss, reg, name, scratch1,
                                        scratch2);
-
-      if (!FLAG_eliminate_prototype_chain_checks) {
-        __ mov(scratch1, FieldOperand(reg, HeapObject::kMapOffset));
-        __ mov(holder_reg, FieldOperand(scratch1, Map::kPrototypeOffset));
-      }
-    } else {
-      Register map_reg = scratch1;
-      if (!FLAG_eliminate_prototype_chain_checks) {
-        __ mov(map_reg, FieldOperand(reg, HeapObject::kMapOffset));
-      }
-      if (current_map->IsJSGlobalObjectMap()) {
-        GenerateCheckPropertyCell(masm(), Handle<JSGlobalObject>::cast(current),
-                                  name, scratch2, miss);
-      } else if (!FLAG_eliminate_prototype_chain_checks &&
-                 (depth != 1 || check == CHECK_ALL_MAPS)) {
-        Handle<WeakCell> cell = Map::WeakCellForMap(current_map);
-        __ CmpWeakValue(map_reg, cell, scratch2);
-        __ j(not_equal, miss);
-      }
-      if (!FLAG_eliminate_prototype_chain_checks) {
-        __ mov(holder_reg, FieldOperand(map_reg, Map::kPrototypeOffset));
-      }
     }
 
     reg = holder_reg;  // From now on the object will be in holder_reg.
@@ -548,17 +525,8 @@
   // Log the check depth.
   LOG(isolate(), IntEvent("check-maps-depth", depth + 1));
 
-  if (!FLAG_eliminate_prototype_chain_checks &&
-      (depth != 0 || check == CHECK_ALL_MAPS)) {
-    // Check the holder map.
-    __ mov(scratch1, FieldOperand(reg, HeapObject::kMapOffset));
-    Handle<WeakCell> cell = Map::WeakCellForMap(current_map);
-    __ CmpWeakValue(scratch1, cell, scratch2);
-    __ j(not_equal, miss);
-  }
-
   bool return_holder = return_what == RETURN_HOLDER;
-  if (FLAG_eliminate_prototype_chain_checks && return_holder && depth != 0) {
+  if (return_holder && depth != 0) {
     __ LoadWeakValue(reg, isolate()->factory()->NewWeakCell(current), miss);
   }
 
@@ -604,7 +572,7 @@
 void NamedLoadHandlerCompiler::GenerateLoadInterceptorWithFollowup(
     LookupIterator* it, Register holder_reg) {
   DCHECK(holder()->HasNamedInterceptor());
-  DCHECK(!holder()->GetNamedInterceptor()->getter()->IsUndefined());
+  DCHECK(!holder()->GetNamedInterceptor()->getter()->IsUndefined(isolate()));
 
   // Compile the interceptor call, followed by inline code to load the
   // property from further up the prototype chain if the call fails.
@@ -671,7 +639,7 @@
 
 void NamedLoadHandlerCompiler::GenerateLoadInterceptor(Register holder_reg) {
   DCHECK(holder()->HasNamedInterceptor());
-  DCHECK(!holder()->GetNamedInterceptor()->getter()->IsUndefined());
+  DCHECK(!holder()->GetNamedInterceptor()->getter()->IsUndefined(isolate()));
   // Call the runtime system to load the interceptor.
   __ pop(scratch2());  // save old return address
   PushInterceptorArguments(masm(), receiver(), holder_reg, this->name(),
@@ -692,7 +660,7 @@
   __ push(holder_reg);
   // If the callback cannot leak, then push the callback directly,
   // otherwise wrap it in a weak cell.
-  if (callback->data()->IsUndefined() || callback->data()->IsSmi()) {
+  if (callback->data()->IsUndefined(isolate()) || callback->data()->IsSmi()) {
     __ Push(callback);
   } else {
     Handle<WeakCell> cell = isolate()->factory()->NewWeakCell(callback);
diff --git a/src/ic/x87/ic-x87.cc b/src/ic/x87/ic-x87.cc
index 9491954..9db5591 100644
--- a/src/ic/x87/ic-x87.cc
+++ b/src/ic/x87/ic-x87.cc
@@ -708,15 +708,6 @@
   __ TailCallRuntime(Runtime::kKeyedGetProperty);
 }
 
-
-void StoreIC::GenerateMegamorphic(MacroAssembler* masm) {
-  // This shouldn't be called.
-  // TODO(mvstanton): remove this method.
-  __ int3();
-  return;
-}
-
-
 static void StoreIC_PushArgs(MacroAssembler* masm) {
   Register receiver = StoreDescriptor::ReceiverRegister();
   Register name = StoreDescriptor::NameRegister();
@@ -836,8 +827,9 @@
   // condition code uses at the patched jump.
   uint8_t delta = *reinterpret_cast<uint8_t*>(delta_address);
   if (FLAG_trace_ic) {
-    PrintF("[  patching ic at %p, test=%p, delta=%d\n", address,
-           test_instruction_address, delta);
+    PrintF("[  patching ic at %p, test=%p, delta=%d\n",
+           static_cast<void*>(address),
+           static_cast<void*>(test_instruction_address), delta);
   }
 
   // Patch with a short conditional jump. Enabling means switching from a short