Check in LLVM r95781.
diff --git a/test/CodeGen/builtinmemcpy.c b/test/CodeGen/builtinmemcpy.c
new file mode 100644
index 0000000..93253c5
--- /dev/null
+++ b/test/CodeGen/builtinmemcpy.c
@@ -0,0 +1,3 @@
+// RUN: %clang_cc1 -emit-llvm < %s -o - | grep "llvm.memcpy"
+
+char* x(char* a, char* b) {return __builtin_memcpy(a, b, 4);}