use ArgOperand API

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106707 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/CodeGenPrepare.cpp b/lib/Transforms/Scalar/CodeGenPrepare.cpp
index 93e9bfb..cf239b7 100644
--- a/lib/Transforms/Scalar/CodeGenPrepare.cpp
+++ b/lib/Transforms/Scalar/CodeGenPrepare.cpp
@@ -559,7 +559,7 @@
   // Lower all uses of llvm.objectsize.*
   IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI);
   if (II && II->getIntrinsicID() == Intrinsic::objectsize) {
-    bool Min = (cast<ConstantInt>(II->getOperand(2))->getZExtValue() == 1);
+    bool Min = (cast<ConstantInt>(II->getArgOperand(1))->getZExtValue() == 1);
     const Type *ReturnTy = CI->getType();
     Constant *RetVal = ConstantInt::get(ReturnTy, Min ? 0 : -1ULL);    
     CI->replaceAllUsesWith(RetVal);