17973211493

Committed 24 Sep 2025 10:00AM UTC coverage: 61.252% (+0.03%) from 61.22%

Build # 17973211493

Build Type

Pull #243

github

Committed by

web-flow

Commit Message

Merge 10606d1fc into c36de2b31

Pull Request Pull Request #243: Make loopindex stable

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9 of 10 new or added lines in 3 files covered. (90.0%)

3 existing lines in 1 file now uncovered.

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64.21

/src/analysis/loop_analysis.cpp

#include "sdfg/analysis/loop_analysis.h"
#include <unordered_set>
#include <vector>

#include "sdfg/analysis/assumptions_analysis.h"
#include "sdfg/structured_control_flow/structured_loop.h"
#include "sdfg/symbolic/conjunctive_normal_form.h"
#include "sdfg/symbolic/series.h"

namespace sdfg {
namespace analysis {

LoopAnalysis::LoopAnalysis(StructuredSDFG& sdfg) : Analysis(sdfg), loops_(), loop_tree_(DFSLoopComparator(&loops_)) {}

void LoopAnalysis::
    run(structured_control_flow::ControlFlowNode& scope, structured_control_flow::ControlFlowNode* parent_loop) {
    std::list<structured_control_flow::ControlFlowNode*> queue = {&scope};
    while (!queue.empty()) {
        auto current = queue.front();
        queue.pop_front();

        // Loop detected
        if (auto while_stmt = dynamic_cast<structured_control_flow::While*>(current)) {
            this->loops_.push_back(while_stmt);
            this->loop_tree_[while_stmt] = parent_loop;
        } else if (auto loop_stmt = dynamic_cast<structured_control_flow::StructuredLoop*>(current)) {
            this->loops_.push_back(loop_stmt);
            this->loop_tree_[loop_stmt] = parent_loop;
        }

        if (dynamic_cast<structured_control_flow::Block*>(current)) {
            continue;
        } else if (auto sequence_stmt = dynamic_cast<structured_control_flow::Sequence*>(current)) {
            for (size_t i = 0; i < sequence_stmt->size(); i++) {
                queue.push_back(&sequence_stmt->at(i).first);
            }
        } else if (auto if_else_stmt = dynamic_cast<structured_control_flow::IfElse*>(current)) {
            for (size_t i = 0; i < if_else_stmt->size(); i++) {
                queue.push_back(&if_else_stmt->at(i).first);
            }
        } else if (auto while_stmt = dynamic_cast<structured_control_flow::While*>(current)) {
            this->run(while_stmt->root(), while_stmt);
        } else if (auto for_stmt = dynamic_cast<structured_control_flow::StructuredLoop*>(current)) {
            this->run(for_stmt->root(), for_stmt);
        } else if (dynamic_cast<structured_control_flow::Break*>(current)) {
            continue;
        } else if (dynamic_cast<structured_control_flow::Continue*>(current)) {
            continue;
        } else if (dynamic_cast<structured_control_flow::Return*>(current)) {
            continue;
        } else {
            throw std::runtime_error("Unsupported control flow node type");
        }
    }
}

void LoopAnalysis::run(AnalysisManager& analysis_manager) {
    this->loops_.clear();
    this->loop_tree_.clear();
    this->run(this->sdfg_.root(), nullptr);
}

const std::vector<structured_control_flow::ControlFlowNode*> LoopAnalysis::loops() const { return this->loops_; }

structured_control_flow::ControlFlowNode* LoopAnalysis::find_loop_by_indvar(const std::string& indvar) {
    for (auto& loop : this->loops_) {
        if (auto loop_stmt = dynamic_cast<structured_control_flow::StructuredLoop*>(loop)) {
            if (loop_stmt->indvar()->get_name() == indvar) {
                return loop;
            }
        }
    }
    return nullptr;
}

bool LoopAnalysis::is_monotonic(structured_control_flow::StructuredLoop* loop, AssumptionsAnalysis& assumptions_analysis) {
    auto assums = assumptions_analysis.get(*loop, true);

    return symbolic::series::is_monotonic(loop->update(), loop->indvar(), assums);
}

bool LoopAnalysis::is_contiguous(structured_control_flow::StructuredLoop* loop, AssumptionsAnalysis& assumptions_analysis) {
    auto assums = assumptions_analysis.get(*loop, true);

    return symbolic::series::is_contiguous(loop->update(), loop->indvar(), assums);
}

symbolic::Expression LoopAnalysis::
    canonical_bound(structured_control_flow::StructuredLoop* loop, AssumptionsAnalysis& assumptions_analysis) {
    if (!LoopAnalysis::is_monotonic(loop, assumptions_analysis)) {
        return SymEngine::null;
    }

    symbolic::CNF cnf;
    try {
        cnf = symbolic::conjunctive_normal_form(loop->condition());
    } catch (const std::runtime_error& e) {
        return SymEngine::null;
    }

    bool has_complex_clauses = false;
    for (auto& clause : cnf) {
        if (clause.size() > 1) {
            has_complex_clauses = true;
            break;
        }
    }
    if (has_complex_clauses) {
        return SymEngine::null;
    }

    auto indvar = loop->indvar();
    symbolic::Expression bound = SymEngine::null;
    for (auto& clause : cnf) {
        for (auto& literal : clause) {
            if (SymEngine::is_a<SymEngine::StrictLessThan>(*literal)) {
                auto lt = SymEngine::rcp_dynamic_cast<const SymEngine::StrictLessThan>(literal);
                auto lhs = lt->get_args()[0];
                auto rhs = lt->get_args()[1];
                if (SymEngine::eq(*lhs, *indvar)) {
                    if (bound == SymEngine::null) {
                        bound = rhs;
                    } else {
                        bound = symbolic::min(bound, rhs);
                    }
                } else {
                    return SymEngine::null;
                }
            } else if (SymEngine::is_a<SymEngine::LessThan>(*literal)) {
                auto le = SymEngine::rcp_dynamic_cast<const SymEngine::LessThan>(literal);
                auto lhs = le->get_args()[0];
                auto rhs = le->get_args()[1];
                if (SymEngine::eq(*lhs, *indvar)) {
                    if (bound == SymEngine::null) {
                        bound = symbolic::add(rhs, symbolic::one());
                    } else {
                        bound = symbolic::min(bound, symbolic::add(rhs, symbolic::one()));
                    }
                } else {
                    return SymEngine::null;
                }
            } else {
                return SymEngine::null;
            }
        }
    }

    return bound;
}

symbolic::Integer LoopAnalysis::stride(structured_control_flow::StructuredLoop* loop) {
    auto expr = loop->update();
    auto indvar = loop->indvar();

    if (SymEngine::is_a<SymEngine::Add>(*expr)) {
        auto add_expr = SymEngine::rcp_static_cast<const SymEngine::Add>(expr);
        if (add_expr->get_args().size() != 2) {
            return SymEngine::null;
        }
        auto arg1 = add_expr->get_args()[0];
        auto arg2 = add_expr->get_args()[1];
        if (symbolic::eq(arg1, indvar)) {
            if (SymEngine::is_a<SymEngine::Integer>(*arg2)) {
                return SymEngine::rcp_static_cast<const SymEngine::Integer>(arg2);
            }
        }
        if (symbolic::eq(arg2, indvar)) {
            if (SymEngine::is_a<SymEngine::Integer>(*arg1)) {
                return SymEngine::rcp_static_cast<const SymEngine::Integer>(arg1);
            }
        }
    }
    return SymEngine::null;
}

const std::map<structured_control_flow::ControlFlowNode*, structured_control_flow::ControlFlowNode*, DFSLoopComparator>&
LoopAnalysis::loop_tree() const {
    return this->loop_tree_;
}

structured_control_flow::ControlFlowNode* LoopAnalysis::parent_loop(structured_control_flow::ControlFlowNode* loop
) const {
    return this->loop_tree_.at(loop);
}

const std::vector<structured_control_flow::ControlFlowNode*> LoopAnalysis::outermost_loops() const {
    std::vector<structured_control_flow::ControlFlowNode*> outermost_loops_;
    for (const auto& [loop, parent] : this->loop_tree_) {
        if (parent == nullptr) {
            outermost_loops_.push_back(loop);
        }
    }
    return outermost_loops_;
}

const std::vector<structured_control_flow::ControlFlowNode*> LoopAnalysis::outermost_maps() const {
    std::vector<structured_control_flow::ControlFlowNode*> outermost_maps_;
    for (const auto& [loop, parent] : this->loop_tree_) {
        if (dynamic_cast<structured_control_flow::Map*>(loop)) {
            auto ancestor = parent;
            while (true) {
                if (ancestor == nullptr) {
                    outermost_maps_.push_back(loop);
                    break;
                }
                if (dynamic_cast<structured_control_flow::Map*>(ancestor)) {
                    break;
                }
                ancestor = this->loop_tree_.at(ancestor);
            }
        }
    }
    return outermost_maps_;
}

std::vector<sdfg::structured_control_flow::ControlFlowNode*> LoopAnalysis::
    children(sdfg::structured_control_flow::ControlFlowNode* node) const {
    // Find unique child
    return this->children(node, this->loop_tree_);
};

std::vector<sdfg::structured_control_flow::ControlFlowNode*> LoopAnalysis::children(
    sdfg::structured_control_flow::ControlFlowNode* node,
    const std::map<
        sdfg::structured_control_flow::ControlFlowNode*,
        sdfg::structured_control_flow::ControlFlowNode*,
        DFSLoopComparator>& tree
) const {
    // Find unique child
    std::vector<sdfg::structured_control_flow::ControlFlowNode*> c;
    for (auto& entry : tree) {
        if (entry.second == node) {
            c.push_back(entry.first);
        }
    }
    return c;
};

std::list<std::vector<sdfg::structured_control_flow::ControlFlowNode*>> LoopAnalysis::
    loop_tree_paths(sdfg::structured_control_flow::ControlFlowNode* loop) const {
    return this->loop_tree_paths(loop, this->loop_tree_);
};

std::list<std::vector<sdfg::structured_control_flow::ControlFlowNode*>> LoopAnalysis::loop_tree_paths(
    sdfg::structured_control_flow::ControlFlowNode* loop,
    const std::map<
        sdfg::structured_control_flow::ControlFlowNode*,
        sdfg::structured_control_flow::ControlFlowNode*,
        DFSLoopComparator>& tree
) const {
    // Collect all paths in tree starting from loop recursively (DFS)
    std::list<std::vector<sdfg::structured_control_flow::ControlFlowNode*>> paths;
    auto children = this->children(loop, tree);
    if (children.empty()) {
        paths.push_back({loop});
        return paths;
    }

    for (auto& child : children) {
        auto p = this->loop_tree_paths(child, tree);
        for (auto& path : p) {
            path.insert(path.begin(), loop);
            paths.push_back(path);
        }
    }

    return paths;
};

std::unordered_set<sdfg::structured_control_flow::ControlFlowNode*> LoopAnalysis::
    descendants(sdfg::structured_control_flow::ControlFlowNode* loop) const {
    std::unordered_set<sdfg::structured_control_flow::ControlFlowNode*> desc;
    std::list<sdfg::structured_control_flow::ControlFlowNode*> queue = {loop};
    while (!queue.empty()) {
        auto current = queue.front();
        queue.pop_front();
        auto children = this->children(current, this->loop_tree_);
        for (auto& child : children) {
            if (desc.find(child) == desc.end()) {
                desc.insert(child);
                queue.push_back(child);
            }
        }
    }
    return desc;
}

} // namespace analysis
} // namespace sdfg

1	#include "sdfg/analysis/loop_analysis.h"
2	#include <unordered_set>
3	#include <vector>
4
5	#include "sdfg/analysis/assumptions_analysis.h"
6	#include "sdfg/structured_control_flow/structured_loop.h"
7	#include "sdfg/symbolic/conjunctive_normal_form.h"
8	#include "sdfg/symbolic/series.h"
9
10	namespace sdfg {
11	namespace analysis {
12
13	LoopAnalysis::LoopAnalysis(StructuredSDFG& sdfg) : Analysis(sdfg), loops_(), loop_tree_(DFSLoopComparator(&loops_)) {}	17✔
14
15	void LoopAnalysis::
16	run(structured_control_flow::ControlFlowNode& scope, structured_control_flow::ControlFlowNode* parent_loop) {	54✔
17	std::list<structured_control_flow::ControlFlowNode*> queue = {&scope};	54✔
18	while (!queue.empty()) {	151✔
19	auto current = queue.front();	97✔
20	queue.pop_front();	97✔
21
22	// Loop detected
23	if (auto while_stmt = dynamic_cast<structured_control_flow::While*>(current)) {	97✔
NEW 24	this->loops_.push_back(while_stmt);	×
25	this->loop_tree_[while_stmt] = parent_loop;	×
26	} else if (auto loop_stmt = dynamic_cast<structured_control_flow::StructuredLoop*>(current)) {	97✔
27	this->loops_.push_back(loop_stmt);	37✔
28	this->loop_tree_[loop_stmt] = parent_loop;	37✔
29	}	37✔
30
31	if (dynamic_cast<structured_control_flow::Block*>(current)) {	97✔
32	continue;	5✔
33	} else if (auto sequence_stmt = dynamic_cast<structured_control_flow::Sequence*>(current)) {	92✔
34	for (size_t i = 0; i < sequence_stmt->size(); i++) {	98✔
35	queue.push_back(&sequence_stmt->at(i).first);	43✔
36	}	43✔
37	} else if (auto if_else_stmt = dynamic_cast<structured_control_flow::IfElse*>(current)) {	92✔
38	for (size_t i = 0; i < if_else_stmt->size(); i++) {	×
39	queue.push_back(&if_else_stmt->at(i).first);	×
40	}	×
41	} else if (auto while_stmt = dynamic_cast<structured_control_flow::While*>(current)) {	37✔
42	this->run(while_stmt->root(), while_stmt);	×
43	} else if (auto for_stmt = dynamic_cast<structured_control_flow::StructuredLoop*>(current)) {	37✔
44	this->run(for_stmt->root(), for_stmt);	37✔
45	} else if (dynamic_cast<structured_control_flow::Break*>(current)) {	37✔
46	continue;	×
47	} else if (dynamic_cast<structured_control_flow::Continue*>(current)) {	×
48	continue;	×
49	} else if (dynamic_cast<structured_control_flow::Return*>(current)) {	×
50	continue;	×
51	} else {
52	throw std::runtime_error("Unsupported control flow node type");	×
53	}
54	}
55	}	54✔
56
57	void LoopAnalysis::run(AnalysisManager& analysis_manager) {	17✔
58	this->loops_.clear();	17✔
59	this->loop_tree_.clear();	17✔
60	this->run(this->sdfg_.root(), nullptr);	17✔
61	}	17✔
62
63	const std::vector<structured_control_flow::ControlFlowNode*> LoopAnalysis::loops() const { return this->loops_; }	10✔
64
65	structured_control_flow::ControlFlowNode* LoopAnalysis::find_loop_by_indvar(const std::string& indvar) {	×
66	for (auto& loop : this->loops_) {	×
67	if (auto loop_stmt = dynamic_cast<structured_control_flow::StructuredLoop*>(loop)) {	×
68	if (loop_stmt->indvar()->get_name() == indvar) {	×
69	return loop;	×
70	}
71	}	×
72	}
73	return nullptr;	×
74	}	×
75
76	bool LoopAnalysis::is_monotonic(structured_control_flow::StructuredLoop* loop, AssumptionsAnalysis& assumptions_analysis) {	80✔
77	auto assums = assumptions_analysis.get(*loop, true);	80✔
78
79	return symbolic::series::is_monotonic(loop->update(), loop->indvar(), assums);	80✔
80	}	80✔
81
82	bool LoopAnalysis::is_contiguous(structured_control_flow::StructuredLoop* loop, AssumptionsAnalysis& assumptions_analysis) {	12✔
83	auto assums = assumptions_analysis.get(*loop, true);	12✔
84
85	return symbolic::series::is_contiguous(loop->update(), loop->indvar(), assums);	12✔
86	}	12✔
87
88	symbolic::Expression LoopAnalysis::
89	canonical_bound(structured_control_flow::StructuredLoop* loop, AssumptionsAnalysis& assumptions_analysis) {	13✔
90	if (!LoopAnalysis::is_monotonic(loop, assumptions_analysis)) {	13✔
91	return SymEngine::null;	×
92	}
93
94	symbolic::CNF cnf;	13✔
95	try {
96	cnf = symbolic::conjunctive_normal_form(loop->condition());	13✔
97	} catch (const std::runtime_error& e) {	13✔
98	return SymEngine::null;	×
99	}	×
100
101	bool has_complex_clauses = false;	13✔
102	for (auto& clause : cnf) {	28✔
103	if (clause.size() > 1) {	15✔
104	has_complex_clauses = true;	×
105	break;	×
106	}
107	}
108	if (has_complex_clauses) {	13✔
109	return SymEngine::null;	×
110	}
111
112	auto indvar = loop->indvar();	13✔
113	symbolic::Expression bound = SymEngine::null;	13✔
114	for (auto& clause : cnf) {	28✔
115	for (auto& literal : clause) {	30✔
116	if (SymEngine::is_a<SymEngine::StrictLessThan>(*literal)) {	15✔
117	auto lt = SymEngine::rcp_dynamic_cast<const SymEngine::StrictLessThan>(literal);	13✔
118	auto lhs = lt->get_args()[0];	13✔
119	auto rhs = lt->get_args()[1];	13✔
120	if (SymEngine::eq(lhs, indvar)) {	13✔
121	if (bound == SymEngine::null) {	13✔
122	bound = rhs;	12✔
123	} else {	12✔
124	bound = symbolic::min(bound, rhs);	1✔
125	}
126	} else {	13✔
127	return SymEngine::null;	×
128	}
129	} else if (SymEngine::is_a<SymEngine::LessThan>(*literal)) {	15✔
130	auto le = SymEngine::rcp_dynamic_cast<const SymEngine::LessThan>(literal);	2✔
131	auto lhs = le->get_args()[0];	2✔
132	auto rhs = le->get_args()[1];	2✔
133	if (SymEngine::eq(lhs, indvar)) {	2✔
134	if (bound == SymEngine::null) {	2✔
135	bound = symbolic::add(rhs, symbolic::one());	1✔
136	} else {	1✔
137	bound = symbolic::min(bound, symbolic::add(rhs, symbolic::one()));	1✔
138	}
139	} else {	2✔
140	return SymEngine::null;	×
141	}
142	} else {	2✔
143	return SymEngine::null;	×
144	}
145	}
146	}
147
148	return bound;	13✔
149	}	13✔
150
151	symbolic::Integer LoopAnalysis::stride(structured_control_flow::StructuredLoop* loop) {	×
152	auto expr = loop->update();	×
153	auto indvar = loop->indvar();	×
154
155	if (SymEngine::is_a<SymEngine::Add>(*expr)) {	×
156	auto add_expr = SymEngine::rcp_static_cast<const SymEngine::Add>(expr);	×
157	if (add_expr->get_args().size() != 2) {	×
158	return SymEngine::null;	×
159	}
160	auto arg1 = add_expr->get_args()[0];	×
161	auto arg2 = add_expr->get_args()[1];	×
162	if (symbolic::eq(arg1, indvar)) {	×
163	if (SymEngine::is_a<SymEngine::Integer>(*arg2)) {	×
164	return SymEngine::rcp_static_cast<const SymEngine::Integer>(arg2);	×
165	}
166	}	×
167	if (symbolic::eq(arg2, indvar)) {	×
168	if (SymEngine::is_a<SymEngine::Integer>(*arg1)) {	×
169	return SymEngine::rcp_static_cast<const SymEngine::Integer>(arg1);	×
170	}
171	}	×
172	}	×
173	return SymEngine::null;	×
174	}	×
175
176	const std::map<structured_control_flow::ControlFlowNode, structured_control_flow::ControlFlowNode, DFSLoopComparator>&
177	LoopAnalysis::loop_tree() const {	×
178	return this->loop_tree_;	×
179	}
180
181	structured_control_flow::ControlFlowNode* LoopAnalysis::parent_loop(structured_control_flow::ControlFlowNode* loop	×
182	) const {
183	return this->loop_tree_.at(loop);	×
184	}
185
186	const std::vector<structured_control_flow::ControlFlowNode*> LoopAnalysis::outermost_loops() const {	1✔
187	std::vector<structured_control_flow::ControlFlowNode*> outermost_loops_;	1✔
188	for (const auto& [loop, parent] : this->loop_tree_) {	3✔
189	if (parent == nullptr) {	2✔
190	outermost_loops_.push_back(loop);	1✔
191	}	1✔
192	}
193	return outermost_loops_;	1✔
194	}	1✔
195
196	const std::vector<structured_control_flow::ControlFlowNode*> LoopAnalysis::outermost_maps() const {	×
197	std::vector<structured_control_flow::ControlFlowNode*> outermost_maps_;	×
198	for (const auto& [loop, parent] : this->loop_tree_) {	×
199	if (dynamic_cast<structured_control_flow::Map*>(loop)) {	×
200	auto ancestor = parent;	×
201	while (true) {	×
202	if (ancestor == nullptr) {	×
203	outermost_maps_.push_back(loop);	×
204	break;	×
205	}
206	if (dynamic_cast<structured_control_flow::Map*>(ancestor)) {	×
207	break;	×
208	}
209	ancestor = this->loop_tree_.at(ancestor);	×
210	}
211	}	×
212	}
213	return outermost_maps_;	×
214	}	×
215
216	std::vector<sdfg::structured_control_flow::ControlFlowNode*> LoopAnalysis::
217	children(sdfg::structured_control_flow::ControlFlowNode* node) const {	3✔
218	// Find unique child
219	return this->children(node, this->loop_tree_);	3✔
220	};
221
222	std::vector<sdfg::structured_control_flow::ControlFlowNode*> LoopAnalysis::children(	15✔
223	sdfg::structured_control_flow::ControlFlowNode* node,
224	const std::map<
225	sdfg::structured_control_flow::ControlFlowNode*,
226	sdfg::structured_control_flow::ControlFlowNode*,
227	DFSLoopComparator>& tree
228	) const {
229	// Find unique child
230	std::vector<sdfg::structured_control_flow::ControlFlowNode*> c;	15✔
231	for (auto& entry : tree) {	60✔
232	if (entry.second == node) {	45✔
233	c.push_back(entry.first);	12✔
234	}	12✔
235	}
236	return c;	15✔
237	};	15✔
238
239	std::list<std::vector<sdfg::structured_control_flow::ControlFlowNode*>> LoopAnalysis::
240	loop_tree_paths(sdfg::structured_control_flow::ControlFlowNode* loop) const {	2✔
241	return this->loop_tree_paths(loop, this->loop_tree_);	2✔
242	};
243
244	std::list<std::vector<sdfg::structured_control_flow::ControlFlowNode*>> LoopAnalysis::loop_tree_paths(	6✔
245	sdfg::structured_control_flow::ControlFlowNode* loop,
246	const std::map<
247	sdfg::structured_control_flow::ControlFlowNode*,
248	sdfg::structured_control_flow::ControlFlowNode*,
249	DFSLoopComparator>& tree
250	) const {
251	// Collect all paths in tree starting from loop recursively (DFS)
252	std::list<std::vector<sdfg::structured_control_flow::ControlFlowNode*>> paths;	6✔
253	auto children = this->children(loop, tree);	6✔
254	if (children.empty()) {	6✔
255	paths.push_back({loop});	3✔
256	return paths;	3✔
257	}
258
259	for (auto& child : children) {	7✔
260	auto p = this->loop_tree_paths(child, tree);	4✔
261	for (auto& path : p) {	8✔
262	path.insert(path.begin(), loop);	4✔
263	paths.push_back(path);	4✔
264	}
265	}	4✔
266
267	return paths;	3✔
268	};	6✔
269
270	std::unordered_set<sdfg::structured_control_flow::ControlFlowNode*> LoopAnalysis::
271	descendants(sdfg::structured_control_flow::ControlFlowNode* loop) const {	2✔
272	std::unordered_set<sdfg::structured_control_flow::ControlFlowNode*> desc;	2✔
273	std::list<sdfg::structured_control_flow::ControlFlowNode*> queue = {loop};	2✔
274	while (!queue.empty()) {	8✔
275	auto current = queue.front();	6✔
276	queue.pop_front();	6✔
277	auto children = this->children(current, this->loop_tree_);	6✔
278	for (auto& child : children) {	10✔
279	if (desc.find(child) == desc.end()) {	4✔
280	desc.insert(child);	4✔
281	queue.push_back(child);	4✔
282	}	4✔
283	}
284	}	6✔
285	return desc;	2✔
286	}	2✔
287
288	} // namespace analysis
289	} // namespace sdfg

daisytuner / sdfglib / 17973211493

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