Correct handling of arrays with callbacks in the prototype chain.

src/x64/macro-assembler-x64.cc

Index: src/x64/macro-assembler-x64.cc
diff --git a/src/x64/macro-assembler-x64.cc b/src/x64/macro-assembler-x64.cc
index 075f07cc353e991fd7969a49725599cb5fcfd45b..8f16f54e1b5b4a7d1df3e4022056fca2290a86c2 100644
--- a/src/x64/macro-assembler-x64.cc
+++ b/src/x64/macro-assembler-x64.cc
@@ -4967,6 +4967,31 @@ void MacroAssembler::RecordObjectAllocation(Isolate* isolate,
   PopSafepointRegisters();
 }
 

[danno, 2013/11/04 17:44:44]

nit: two lines between functions

[mvstanton, 2013/11/05 09:06:51]

Done.

+void MacroAssembler::JumpIfDictionaryInPrototypeChain(
+    Register object,
+    Register scratch0,
+    Register scratch1,
+    Label* found) {
+  ASSERT(!(scratch0.is(kScratchRegister) && scratch1.is(kScratchRegister)));
+  ASSERT(!scratch1.is(scratch0));
+  Register current = scratch0;
+  Label loop_again;
+
+  movq(current, object);
+
+  // Loop based on the map going up the prototype chain.
+  bind(&loop_again);
+  movq(current, FieldOperand(current, HeapObject::kMapOffset));
+  movq(scratch1, FieldOperand(current, Map::kBitField2Offset));
+  and_(scratch1, Immediate(Map::kElementsKindMask));
+  shr(scratch1, Immediate(Map::kElementsKindShift));
+  cmpq(scratch1, Immediate(DICTIONARY_ELEMENTS));
+  j(equal, found);
+  movq(current, FieldOperand(current, Map::kPrototypeOffset));
+  CompareRoot(current, Heap::kNullValueRootIndex);
+  j(not_equal, &loop_again);
+}
+
 
 } }  // namespace v8::internal