Implement IC support for Constant Function transitions.

src/x64/stub-cache-x64.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 799 matching lines @@
             miss_restore_name);
       } else if (!holder->HasFastProperties() && !holder->IsJSGlobalProxy()) {
         GenerateDictionaryNegativeLookup(
             masm, miss_restore_name, holder_reg, name, scratch1, scratch2);
       }
     }
   }
 
   Register storage_reg = name_reg;
 
-  if (FLAG_track_fields && representation.IsSmi()) {
+  if (details.type() == CONSTANT_FUNCTION) {
+    Handle<HeapObject> constant(
+        HeapObject::cast(descriptors->GetValue(descriptor)));
+    __ LoadHeapObject(scratch1, constant);
+    __ cmpq(value_reg, scratch1);
+    __ j(not_equal, miss_restore_name);
+  } else if (FLAG_track_fields && representation.IsSmi()) {
     __ JumpIfNotSmi(value_reg, miss_restore_name);
   } else if (FLAG_track_heap_object_fields && representation.IsHeapObject()) {
     __ JumpIfSmi(value_reg, miss_restore_name);
   } else if (FLAG_track_double_fields && representation.IsDouble()) {
     Label do_store, heap_number;
     __ AllocateHeapNumber(storage_reg, scratch1, slow);
 
     __ JumpIfNotSmi(value_reg, &heap_number);
     __ SmiToInteger32(scratch1, value_reg);
     __ cvtlsi2sd(xmm0, scratch1);
@@ skipping 35 matching lines @@
 
   // Update the write barrier for the map field.
   __ RecordWriteField(receiver_reg,
                       HeapObject::kMapOffset,
                       scratch1,
                       scratch2,
                       kDontSaveFPRegs,
                       OMIT_REMEMBERED_SET,
                       OMIT_SMI_CHECK);
 
+  if (details.type() == CONSTANT_FUNCTION) return;
+
   int index = transition->instance_descriptors()->GetFieldIndex(
       transition->LastAdded());
 
   // Adjust for the number of properties stored in the object. Even in the
   // face of a transition we can use the old map here because the size of the
   // object and the number of in-object properties is not going to change.
   index -= object->map()->inobject_properties();
 
   // TODO(verwaest): Share this code as a code stub.
   SmiCheck smi_check = representation.IsTagged()
@@ skipping 2600 matching lines @@
     TailCallBuiltin(masm, Builtins::kKeyedStoreIC_Slow);
   }
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64