diff --git a/llvm/include/llvm/IR/InstrTypes.h b/llvm/include/llvm/IR/InstrTypes.h
--- a/llvm/include/llvm/IR/InstrTypes.h
+++ b/llvm/include/llvm/IR/InstrTypes.h
@@ -1729,13 +1729,15 @@
   /// Extract the byval type for a call or parameter.
   Type *getParamByValType(unsigned ArgNo) const {
     Type *Ty = Attrs.getParamByValType(ArgNo);
-    return Ty ? Ty : getArgOperand(ArgNo)->getType()->getPointerElementType();
+    if (const Function *F = getCalledFunction())
+      return F->getAttributes().getParamByValType(ArgNo);
+    return Ty;
   }
 
   /// Extract the preallocated type for a call or parameter.
   Type *getParamPreallocatedType(unsigned ArgNo) const {
     Type *Ty = Attrs.getParamPreallocatedType(ArgNo);
-    return Ty ? Ty : getArgOperand(ArgNo)->getType()->getPointerElementType();
+    return Ty;
   }
 
   /// Extract the number of dereferenceable bytes for a call or
diff --git a/llvm/unittests/IR/AttributesTest.cpp b/llvm/unittests/IR/AttributesTest.cpp
--- a/llvm/unittests/IR/AttributesTest.cpp
+++ b/llvm/unittests/IR/AttributesTest.cpp
@@ -7,8 +7,12 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/IR/Attributes.h"
-#include "llvm/IR/LLVMContext.h"
+#include "llvm/AsmParser/Parser.h"
 #include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/InstrTypes.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/SourceMgr.h"
 #include "gtest/gtest.h"
 using namespace llvm;
 
@@ -252,4 +256,24 @@
   }
 }
 
+TEST(Attributes, MismatchedByval) {
+  const char *IRString = R"IR(
+    declare void @f(i32* byval(i32))
+    define void @g() {
+      call void @f(i32* null)
+      ret void
+    }
+  )IR";
+
+  SMDiagnostic Err;
+  LLVMContext Context;
+  std::unique_ptr<Module> M = parseAssemblyString(IRString, Err, Context);
+  ASSERT_TRUE(M);
+
+  auto *G = M->getFunction("g");
+  ASSERT_TRUE(G);
+  auto *I = cast<CallBase>(&G->getEntryBlock().front());
+  ASSERT_TRUE(I->getParamByValType(0));
+}
+
 } // end anonymous namespace