Implement CodeGen for __builtin_memcpy.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@51282 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/builtinmemcpy.c b/test/CodeGen/builtinmemcpy.c
new file mode 100644
index 0000000..8600d98
--- /dev/null
+++ b/test/CodeGen/builtinmemcpy.c
@@ -0,0 +1,3 @@
+// RUN: clang -emit-llvm < %s -o - | grep "llvm.memcpy"
+
+char* x(char* a, char* b) {return __builtin_memcpy(a, b, 4);}