diff --git a/sim_fio.c b/sim_fio.c
index 8b297b7d..6890f757 100644
--- a/sim_fio.c
+++ b/sim_fio.c
@@ -50,7 +50,8 @@
    sim_fsize_ex      -       get file size as a t_offset
    sim_fsize_name_ex -       get file size as a t_offset of named file
    sim_buf_copy_swapped -    copy data swapping elements along the way
-   sim_buf_swap_data -       swap data elements inplace in buffer
+   sim_buf_swap_data -       swap data elements inplace in buffer if needed
+   sim_byte_swap_data -      swap data elements inplace in buffer
    sim_shmem_open            create or attach to a shared memory region
    sim_shmem_close           close a shared memory region
 
@@ -109,8 +110,16 @@ sim_taddr_64 = sim_toffset_64 && (sizeof(t_addr) > sizeof(int32));
 return sim_end;
 }
 
+/* Copy little endian data to local buffer swapping if needed */
 void sim_buf_swap_data (void *bptr, size_t size, size_t count)
 {
+if (sim_end || (count == 0) || (size == sizeof (char)))
+    return;
+sim_byte_swap_data (bptr, size, count);
+}
+
+void sim_byte_swap_data (void *bptr, size_t size, size_t count)
+{
 uint32 j;
 int32 k;
 unsigned char by, *sptr, *dptr;
diff --git a/sim_fio.h b/sim_fio.h
index ba7c23a3..b7ef07bf 100644
--- a/sim_fio.h
+++ b/sim_fio.h
@@ -88,6 +88,7 @@ typedef void (*DIR_ENTRY_CALLBACK)(const char *directory,
 t_stat sim_dir_scan (const char *cptr, DIR_ENTRY_CALLBACK entry, void *context);
 
 void sim_buf_swap_data (void *bptr, size_t size, size_t count);
+void sim_byte_swap_data (void *bptr, size_t size, size_t count);
 void sim_buf_copy_swapped (void *dptr, const void *bptr, size_t size, size_t count);
 const char *sim_get_os_error_text (int error);
 typedef struct SHMEM SHMEM;