+/* Attempt to simplify a view by merging ajacent ranges */
+static void flatview_simplify(FlatView *view)
+{
+ unsigned i;
+ FlatRange *r1, *r2;
+
+ for (i = 0; i + 1< view->nr; ++i) {
+ r1 =&view->ranges[i];
+ r2 =&view->ranges[i+1];
+ if (addrrange_end(r1->addr) == r2->addr.start
+&& r1->mr == r2->mr
+&& r1->offset_in_region + r1->addr.size == r2->offset_in_region
+&& r1->dirty_log_mask == r2->dirty_log_mask) {
+ r1->addr.size += r2->addr.size;
+ memmove(r2, r2 + 1, (view->nr - (i + 2)) * sizeof(*r2));
+ --view->nr;
+ --i;
+ }
The --i is pretty subtle. Moving the index variable backwards in a
conditional in a for loop is pretty evil :-) I started writing up why
this was wrong until I noticed that.
I think the following would be more straight forward:
i = 0;
while (i + 1 < view->nr) {
int begin = i, end = i + 1;
while (matches(&view->ranges[begin], &view->ranges[end])) {
end++;
}
memmove(...)
}