r178818 - Add testing case for r178797

[Ulrich Weigand]

Manman Ren wrote:

>Add testing case for r178797

This fails on powerpc64 because it zero-extends return values:

/home/uweigand/llvm/llvm-head/tools/clang/test/CodeGen/tbaa.cpp:45:11:
error: expected string not found in input
// CHECK: define i32 @{{.*}}(
          ^
<stdin>:1:1: note: scanning from here
; ModuleID =
'/home/uweigand/llvm/llvm-head/tools/clang/test/CodeGen/tbaa.cpp'
^
<stdin>:12:1: note: possible intended match here
define zeroext i32 @_Z1gPjP7StructAm(i32* %s, %struct.StructA* %A, i64
%count) #0 {
^

Bye,
Ulrich