[LLVMdev] Puzzles on DenseMap

[maxs]

I wrote some program using DensMap like this:
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SmallDenseMap<Value*, StringRef, 4> OpResult;
Value *VP = GEP->getPointerOperand();
OpResult[VP] = parseVariable(VP);
for(User::op_iterator sId = GEP->idx_begin(), eId = GEP->idx_end(); sId 
!= eId; ++sId) {
          Value *VI = *sId;
          if(dyn_cast<ConstantInt>(*sId)) OpResult[VI] = parseConstant(VI);
          else OpResult[VI] = parseVariable(VI);
}
....
===============================
When I visit OpResult like this:
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std::string result = OpResult[VP];
=====================
And this statement changes the other data in DenseMap. Why?