Merge bleeding edge revision 6020 to 2.4 branch.

src/ia32/codegen-ia32.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 7600 matching lines @@
   // Smi-tagging is equivalent to multiplying by 2.
   STATIC_ASSERT(kSmiTag == 0);
   STATIC_ASSERT(kSmiTagSize == 1);
 
   // Check that both indices are smis.
   __ mov(tmp2.reg(), index1.reg());
   __ or_(tmp2.reg(), Operand(index2.reg()));
   __ test(tmp2.reg(), Immediate(kSmiTagMask));
   deferred->Branch(not_zero);
 
+  // Check that both indices are valid.
+  __ mov(tmp2.reg(), FieldOperand(object.reg(), JSArray::kLengthOffset));
+  __ cmp(tmp2.reg(), Operand(index1.reg()));
+  deferred->Branch(below_equal);
+  __ cmp(tmp2.reg(), Operand(index2.reg()));
+  deferred->Branch(below_equal);
+
   // Bring addresses into index1 and index2.
   __ lea(index1.reg(), FixedArrayElementOperand(tmp1.reg(), index1.reg()));
   __ lea(index2.reg(), FixedArrayElementOperand(tmp1.reg(), index2.reg()));
 
   // Swap elements.
   __ mov(object.reg(), Operand(index1.reg(), 0));
   __ mov(tmp2.reg(),   Operand(index2.reg(), 0));
   __ mov(Operand(index2.reg(), 0), object.reg());
   __ mov(Operand(index1.reg(), 0), tmp2.reg());
 
@@ skipping 2508 matching lines @@
   masm.GetCode(&desc);
   // Call the function from C++.
   return FUNCTION_CAST<MemCopyFunction>(buffer);
 }
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32