maple_tree: move the check forward to avoid static check warning

Patch series "Some cleanups of maple tree", v2.

These are some small cleanups of maple tree.


This patch (of 5):

Put the check for gap before its reference to avoid Smatch static check
warnings.  This is not a bug, it's just a validation program.  Even with
this change, Smatch may still generate warnings because MT_BUG_ON()
doesn't necessarily stop the program.  It may require fixing Smatch itself
to avoid these warnings.

Link: https://lkml.kernel.org/r/20231120070937.35481-1-zhangpeng.00@bytedance.com
Link: https://lkml.kernel.org/r/20231120070937.35481-2-zhangpeng.00@bytedance.comSigned-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: http://lists.infradead.org/pipermail/maple-tree/2023-November/003046.htmlReviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

lib/maple_tree.c

@@ -7257,6 +7257,7 @@ static void mas_validate_gaps(struct ma_state *mas)
 
 counted:
 	if (mt == maple_arange_64) {
+		MT_BUG_ON(mas->tree, !gaps);
 		offset = ma_meta_gap(node, mt);
 		if (offset > i) {
 			pr_err("gap offset %p[%u] is invalid\n", node, offset);
@@ -7269,7 +7270,6 @@ static void mas_validate_gaps(struct ma_state *mas)
 			MT_BUG_ON(mas->tree, 1);
 		}
 
-		MT_BUG_ON(mas->tree, !gaps);
 		for (i++ ; i < mt_slot_count(mte); i++) {
 			if (gaps[i] != 0) {
 				pr_err("gap %p[%u] beyond node limit != 0\n",