1 /* Copyright (c) 2008-2023. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 #include "src/mc/explo/odpor/WakeupTreeIterator.hpp"
7 #include "src/mc/explo/odpor/WakeupTree.hpp"
9 namespace simgrid::mc::odpor {
11 WakeupTreeIterator::WakeupTreeIterator(const WakeupTree& tree) : root_list{tree.root_}
13 post_order_iteration.push(root_list.begin());
14 push_until_left_most_found();
17 void WakeupTreeIterator::push_until_left_most_found()
19 // INVARIANT: Since we are traversing over a tree,
20 // there are no cycles. This means that at least
21 // one node in the tree won't have any children,
22 // so the loop will eventually terminate
23 auto* cur_top_node = *post_order_iteration.top();
24 while (not cur_top_node->is_leaf()) {
25 // INVARIANT: Since we push children in
26 // reverse order (right-most to left-most),
27 // we ensure that we'll always process left-most
29 auto& children = cur_top_node->children_;
31 for (auto iter = children.rbegin(); iter != children.rend(); ++iter) {
32 // iter.base() points one element past where we seek; hence,
33 // we move it over one position
34 post_order_iteration.push(std::prev(iter.base()));
36 cur_top_node = *post_order_iteration.top();
40 void WakeupTreeIterator::increment()
42 // If there are no nodes in the stack, we've
43 // completed the traversal: there's nothing left
45 if (post_order_iteration.empty()) {
49 auto prev_top_handle = post_order_iteration.top();
50 post_order_iteration.pop();
52 // If there are now no longer any nodes left,
53 // we know that `prev_top` must be the original
54 // root; that is, we were *just* pointing at the
55 // original root, so we're done
56 if (post_order_iteration.empty()) {
60 // Otherwise, look at the next top node. If
61 // `prev_top` is that node's right-most child,
62 // then we don't attempt to re-add `next_top`'s
63 // children again for we would have already seen them.
64 // To actually determine "right-most", we check if
65 // moving over to the right one spot brings us to the
66 // end of the candidate parent's list
67 const auto* next_top_node = *post_order_iteration.top();
68 if ((++prev_top_handle) != next_top_node->get_ordered_children().end()) {
69 push_until_left_most_found();
73 } // namespace simgrid::mc::odpor