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
diff --git a/lib/Transforms/IPO/IPConstantPropagation.cpp b/lib/Transforms/IPO/IPConstantPropagation.cpp
index bb24486..95c3f4e 100644
--- a/lib/Transforms/IPO/IPConstantPropagation.cpp
+++ b/lib/Transforms/IPO/IPConstantPropagation.cpp
@@ -130,7 +130,8 @@
   Function::arg_iterator AI = F.arg_begin();
   for (unsigned i = 0, e = ArgumentConstants.size(); i != e; ++i, ++AI) {
     // Do we have a constant argument?
-    if (ArgumentConstants[i].second || AI->use_empty())
+    if (ArgumentConstants[i].second || AI->use_empty() || 
+        (AI->hasByValAttr() && isa<PointerType>(AI->getType())))
       continue;
   
     Value *V = ArgumentConstants[i].first;