MIPS: Properly check fast array property in StoreIC::GenerateArrayLength.

src/mips/ic-mips.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 1553 matching lines @@
 
   // Check that elements are FixedArray.
   // We rely on StoreIC_ArrayLength below to deal with all types of
   // fast elements (including COW).
   __ lw(scratch, FieldMemOperand(receiver, JSArray::kElementsOffset));
   __ GetObjectType(scratch, scratch, scratch);
   __ Branch(&miss, ne, scratch, Operand(FIXED_ARRAY_TYPE));
 
   // Check that the array has fast properties, otherwise the length
   // property might have been redefined.
-  // TODO(mstarzinger): Port this check to MIPS.
+  __ lw(scratch, FieldMemOperand(receiver, JSArray::kPropertiesOffset));
+  __ lw(scratch, FieldMemOperand(scratch, FixedArray::kMapOffset));
+  __ LoadRoot(at, Heap::kHashTableMapRootIndex);
+  __ Branch(&miss, eq, scratch, Operand(at));
 
   // Check that value is a smi.
   __ JumpIfNotSmi(value, &miss);
 
   // Prepare tail call to StoreIC_ArrayLength.
   __ Push(receiver, value);
 
   ExternalReference ref = ExternalReference(IC_Utility(kStoreIC_ArrayLength),
                                             masm->isolate());
   __ TailCallExternalReference(ref, 2, 1);
@@ skipping 164 matching lines @@
     Register reg = Register::from_code(Assembler::GetRs(instr_at_patch));
     patcher.masm()->andi(at, reg, kSmiTagMask);
     patcher.ChangeBranchCondition(eq);
   }
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS