Don't constant propagate byval pointers, since they are not really pointers, but

rather structs passed by value.
This fixes PR5038.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82689 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Scalar/SCCP.cpp

@@ -1267,6 +1267,10 @@ CallOverdefined:
   for (Function::arg_iterator AI = F->arg_begin(), E = F->arg_end();
        AI != E; ++AI, ++CAI) {
     LatticeVal &IV = ValueState[AI];
+    if (AI->hasByValAttr() && isa<PointerType>(AI->getType())) {
+      IV.markOverdefined();
+      continue;
+    }
     if (!IV.isOverdefined())
       mergeInValue(IV, AI, getValueState(*CAI));
   }