py: Use memmove instead of memcpy when appropriate.

dpgeorge · dpgeorge · commit 17ae2395c245 · 2014-08-29T21:07:54.000+01:00
Found this bug by running unix/ tests with DEBUG=1 enabled when
compiling.
diff --git a/py/obj.h b/py/obj.h
@@ -585,8 +585,8 @@ mp_obj_t mp_seq_extract_slice(uint len, const mp_obj_t *seq, mp_bound_slice_t *i
 #define mp_seq_replace_slice_no_grow(dest, dest_len, beg, end, slice, slice_len, item_t) \
     /*printf("memcpy(%p, %p, %d)\n", dest + beg, slice, slice_len * sizeof(item_t));*/ \
     memcpy(dest + beg, slice, slice_len * sizeof(item_t)); \
-    /*printf("memcpy(%p, %p, %d)\n", dest + (beg + slice_len), dest + end, (dest_len - end) * sizeof(item_t));*/ \
-    memcpy(dest + (beg + slice_len), dest + end, (dest_len - end) * sizeof(item_t));
+    /*printf("memmove(%p, %p, %d)\n", dest + (beg + slice_len), dest + end, (dest_len - end) * sizeof(item_t));*/ \
+    memmove(dest + (beg + slice_len), dest + end, (dest_len - end) * sizeof(item_t));
 
 #define mp_seq_replace_slice_grow_inplace(dest, dest_len, beg, end, slice, slice_len, len_adj, item_t) \
     /*printf("memmove(%p, %p, %d)\n", dest + beg + len_adj, dest + beg, (dest_len - beg) * sizeof(item_t));*/ \
diff --git a/py/objlist.c b/py/objlist.c
@@ -274,7 +274,7 @@ STATIC mp_obj_t list_pop(uint n_args, const mp_obj_t *args) {
     uint index = mp_get_index(self->base.type, self->len, n_args == 1 ? MP_OBJ_NEW_SMALL_INT(-1) : args[1], false);
     mp_obj_t ret = self->items[index];
     self->len -= 1;
-    memcpy(self->items + index, self->items + index + 1, (self->len - index) * sizeof(mp_obj_t));
+    memmove(self->items + index, self->items + index + 1, (self->len - index) * sizeof(mp_obj_t));
     // Clear stale pointer from slot which just got freed to prevent GC issues
     self->items[self->len] = MP_OBJ_NULL;
     if (self->alloc > LIST_MIN_ALLOC && self->alloc > 2 * self->len) {
diff --git a/py/objstr.c b/py/objstr.c
@@ -567,7 +567,7 @@ STATIC mp_obj_t str_rsplit(uint n_args, const mp_obj_t *args) {
         if (idx != 0) {
             // We split less parts than split limit, now go cleanup surplus
             int used = org_splits + 1 - idx;
-            memcpy(res->items, &res->items[idx], used * sizeof(mp_obj_t));
+            memmove(res->items, &res->items[idx], used * sizeof(mp_obj_t));
             mp_seq_clear(res->items, used, res->alloc, sizeof(*res->items));
             res->len = used;
         }

Original file line number	Diff line number	Diff line change
`@@ -567,7 +567,7 @@ STATIC mp_obj_t str_rsplit(uint n_args, const mp_obj_t *args) {`
`567`	`567`	`if (idx != 0) {`
`568`	`568`	`// We split less parts than split limit, now go cleanup surplus`
`569`	`569`	`int used = org_splits + 1 - idx;`
`570`		`- memcpy(res->items, &res->items[idx], used * sizeof(mp_obj_t));`
	`570`	`+ memmove(res->items, &res->items[idx], used * sizeof(mp_obj_t));`
`571`	`571`	`mp_seq_clear(res->items, used, res->alloc, sizeof(*res->items));`
`572`	`572`	`res->len = used;`
`573`	`573`	`}`