Allow property indexes to refer to slots inside the object header.

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 332 matching lines @@
 }
 
 
 // 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,
-                                            int index) {
-  // Adjust for the number of properties stored in the holder.
-  index -= holder->map()->inobject_properties();
-  if (index < 0) {
-    // Get the property straight out of the holder.
-    int offset = holder->map()->instance_size() + (index * kPointerSize);
+                                            PropertyIndex index) {
+  if (index.IsHeaderIndex()) {
+    int offset = index.HeaderIndex() * kPointerSize;
     __ movq(dst, FieldOperand(src, offset));
   } else {
-    // Calculate the offset into the properties array.
-    int offset = index * kPointerSize + FixedArray::kHeaderSize;
-    __ movq(dst, FieldOperand(src, JSObject::kPropertiesOffset));
-    __ movq(dst, FieldOperand(dst, offset));
+    // Adjust for the number of properties stored in the holder.
+    int slot = index.FieldIndex() - holder->map()->inobject_properties();
+    if (slot < 0) {
+      // Get the property straight out of the holder.
+      int offset = holder->map()->instance_size() + (slot * kPointerSize);
+      __ movq(dst, FieldOperand(src, offset));
+    } else {
+      // Calculate the offset into the properties array.
+      int offset = slot * kPointerSize + FixedArray::kHeaderSize;
+      __ movq(dst, FieldOperand(src, JSObject::kPropertiesOffset));
+      __ movq(dst, FieldOperand(dst, offset));
+    }
   }
 }
 
 
 static void PushInterceptorArguments(MacroAssembler* masm,
                                      Register receiver,
                                      Register holder,
                                      Register name,
                                      Handle<JSObject> holder_obj) {
   __ push(name);
@@ skipping 3725 matching lines @@
     __ jmp(ic_slow, RelocInfo::CODE_TARGET);
   }
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64