Merge bleeding edge revision 6020 to 2.4 branch.

src/x64/codegen-x64.cc

 // Copyright 2010 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 6895 matching lines @@
   // Check the object's elements are in fast case and writable.
   __ movq(tmp1.reg(), FieldOperand(object.reg(), JSObject::kElementsOffset));
   __ CompareRoot(FieldOperand(tmp1.reg(), HeapObject::kMapOffset),
                  Heap::kFixedArrayMapRootIndex);
   deferred->Branch(not_equal);
 
   // Check that both indices are smis.
   Condition both_smi = masm()->CheckBothSmi(index1.reg(), index2.reg());
   deferred->Branch(NegateCondition(both_smi));
 
+  // Check that both indices are valid.
+  __ movq(tmp2.reg(), FieldOperand(object.reg(), JSArray::kLengthOffset));
+  __ cmpl(tmp2.reg(), index1.reg());
+  deferred->Branch(below_equal);
+  __ cmpl(tmp2.reg(), index2.reg());
+  deferred->Branch(below_equal);
+
   // Bring addresses into index1 and index2.
   __ SmiToInteger32(index1.reg(), index1.reg());
   __ lea(index1.reg(), FieldOperand(tmp1.reg(),
                                     index1.reg(),
                                     times_pointer_size,
                                     FixedArray::kHeaderSize));
   __ SmiToInteger32(index2.reg(), index2.reg());
   __ lea(index2.reg(), FieldOperand(tmp1.reg(),
                                     index2.reg(),
                                     times_pointer_size,
@@ skipping 1997 matching lines @@
 #undef __
 
 void RecordWriteStub::Generate(MacroAssembler* masm) {
   masm->RecordWriteHelper(object_, addr_, scratch_);
   masm->ret(0);
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64