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daisytuner / docc / 28444389515

30 Jun 2026 12:30PM UTC coverage: 62.111% (-0.004%) from 62.115%
28444389515

Pull #820

github

web-flow
Merge 3bbdb07a8 into c00d169ce
Pull Request #820: Maximize over sibling sizes for nested GPU dimensions

3 of 3 new or added lines in 1 file covered. (100.0%)

3 existing lines in 1 file now uncovered.

39413 of 63456 relevant lines covered (62.11%)

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67.4
/opt/src/transformations/loop_interchange.cpp
1
#include "sdfg/transformations/loop_interchange.h"
2

3
#include <isl/ctx.h>
4
#include <isl/map.h>
5
#include <isl/options.h>
6
#include <isl/set.h>
7

8
#include "sdfg/analysis/data_dependency_analysis.h"
9
#include "sdfg/analysis/loop_carried_dependency_analysis.h"
10
#include "sdfg/exceptions.h"
11
#include "sdfg/structured_control_flow/for.h"
12
#include "sdfg/structured_control_flow/structured_loop.h"
13
#include "sdfg/symbolic/polynomials.h"
14

15
namespace sdfg {
16
namespace transformations {
17

18
/// Check that a 2D delta set is lex-non-negative in the post-interchange order.
19
/// `new_outer_dim` is the index (0 or 1) of the dimension that becomes the
20
/// new outer loop after interchange.
21
/// Returns false (unsafe) if any delta vector is lex-negative in the new order.
22
static bool is_interchange_legal_2d(const std::string& deltas_str, int new_outer_dim) {
3✔
23
    if (deltas_str.empty()) {
3✔
24
        return false;
×
25
    }
×
26

27
    isl_ctx* ctx = isl_ctx_alloc();
3✔
28
    isl_options_set_on_error(ctx, ISL_ON_ERROR_CONTINUE);
3✔
29

30
    isl_set* deltas = isl_set_read_from_str(ctx, deltas_str.c_str());
3✔
31
    if (!deltas) {
3✔
32
        isl_ctx_free(ctx);
×
33
        return false;
×
34
    }
×
35

36
    int n_dims = isl_set_dim(deltas, isl_dim_set);
3✔
37
    if (n_dims != 2) {
3✔
38
        isl_set_free(deltas);
×
39
        isl_ctx_free(ctx);
×
40
        return false;
×
41
    }
×
42

43
    // Build lex-negative constraint in post-interchange order.
44
    // If new_outer is dim0: lex-neg = { [x, y] : x < 0 or (x = 0 and y < 0) }
45
    // If new_outer is dim1: lex-neg = { [x, y] : y < 0 or (y = 0 and x < 0) }
46
    const char* lex_neg_str = (new_outer_dim == 0) ? "{ [x, y] : x < 0 or (x = 0 and y < 0) }"
3✔
47
                                                   : "{ [x, y] : y < 0 or (y = 0 and x < 0) }";
3✔
48

49
    isl_set* lex_neg = isl_set_read_from_str(ctx, lex_neg_str);
3✔
50
    isl_set* violation = isl_set_intersect(deltas, lex_neg);
3✔
51
    bool legal = isl_set_is_empty(violation);
3✔
52
    isl_set_free(violation);
3✔
53
    isl_ctx_free(ctx);
3✔
54

55
    return legal;
3✔
56
}
3✔
57

58
/// Check that a 1D delta set {[d]} has no negative values.
59
/// After interchange the inner loop becomes the outer, so we need d >= 0.
60
static bool is_interchange_legal_1d(const std::string& deltas_str) {
8✔
61
    if (deltas_str.empty()) {
8✔
62
        return false;
×
63
    }
×
64

65
    isl_ctx* ctx = isl_ctx_alloc();
8✔
66
    isl_options_set_on_error(ctx, ISL_ON_ERROR_CONTINUE);
8✔
67

68
    isl_set* deltas = isl_set_read_from_str(ctx, deltas_str.c_str());
8✔
69
    if (!deltas) {
8✔
70
        isl_ctx_free(ctx);
×
71
        return false;
×
72
    }
×
73

74
    int n_dims = isl_set_dim(deltas, isl_dim_set);
8✔
75
    if (n_dims != 1) {
8✔
76
        isl_set_free(deltas);
×
77
        isl_ctx_free(ctx);
×
78
        return false;
×
79
    }
×
80

81
    isl_set* neg = isl_set_read_from_str(ctx, "{ [x] : x < 0 }");
8✔
82
    isl_set* violation = isl_set_intersect(deltas, neg);
8✔
83
    bool legal = isl_set_is_empty(violation);
8✔
84
    isl_set_free(violation);
8✔
85
    isl_ctx_free(ctx);
8✔
86

87
    return legal;
8✔
88
}
8✔
89

90
/// Extract the upper bound from a condition of the form `indvar [+ offset] < expr`,
91
/// or `And(indvar < expr1, indvar < expr2, ...)`.
92
/// Returns the equivalent RHS such that `indvar < result` (using min for conjunctions).
93
/// Returns SymEngine::null if the condition is not extractable.
94
static symbolic::Expression
95
extract_strict_upper_bound(const symbolic::Condition& condition, const symbolic::Symbol& indvar) {
33✔
96
    if (SymEngine::is_a<SymEngine::StrictLessThan>(*condition)) {
33✔
97
        auto lt = SymEngine::rcp_static_cast<const SymEngine::StrictLessThan>(condition);
33✔
98
        auto lhs = lt->get_arg1();
33✔
99
        auto rhs = lt->get_arg2();
33✔
100
        if (symbolic::eq(lhs, indvar)) {
33✔
101
            return rhs;
23✔
102
        }
23✔
103
        // Handle: Lt(indvar + offset, bound) → indvar < bound - offset
104
        if (symbolic::uses(lhs, indvar->get_name()) && !symbolic::uses(rhs, indvar->get_name())) {
10✔
105
            auto offset = symbolic::sub(lhs, indvar);
10✔
106
            if (!symbolic::uses(offset, indvar->get_name())) {
10✔
107
                return symbolic::sub(rhs, offset);
10✔
108
            }
10✔
109
        }
10✔
110
    }
10✔
111
    // Handle: And(cond1, cond2, ...) → min of extracted bounds
112
    if (SymEngine::is_a<SymEngine::And>(*condition)) {
×
113
        auto conj = SymEngine::rcp_static_cast<const SymEngine::And>(condition);
×
114
        symbolic::Expression result = SymEngine::null;
×
115
        for (auto& arg : conj->get_container()) {
×
116
            auto bound = extract_strict_upper_bound(SymEngine::rcp_dynamic_cast<const SymEngine::Boolean>(arg), indvar);
×
117
            if (bound == SymEngine::null) return SymEngine::null;
×
118
            if (result == SymEngine::null) {
×
119
                result = bound;
×
120
            } else {
×
121
                result = symbolic::min(result, bound);
×
122
            }
×
123
        }
×
124
        return result;
×
125
    }
×
126
    return SymEngine::null;
×
127
}
×
128

129
/// Decompose `expr` as `coefficient * sym + constant` where coefficient is a
130
/// positive integer.  Returns the (coefficient, constant) pair on success, or
131
/// (null, null) when the expression is not affine in `sym` or the coefficient
132
/// is not a positive integer.
133
struct AffineDecomp {
134
    symbolic::Expression coefficient = SymEngine::null;
135
    symbolic::Expression constant = SymEngine::null;
136
    explicit operator bool() const { return coefficient != SymEngine::null; }
21✔
137
};
138

139
static AffineDecomp check_affine(const symbolic::Expression& expr, const symbolic::Symbol& sym) {
33✔
140
    symbolic::SymbolVec syms = {sym};
33✔
141
    auto poly = symbolic::polynomial(expr, syms);
33✔
142
    if (poly == SymEngine::null) return {};
33✔
143
    auto coeffs = symbolic::affine_coefficients(poly);
33✔
144
    if (coeffs.empty()) return {};
33✔
145
    auto coeff = coeffs[sym];
33✔
146
    // Coefficient must be a positive integer
147
    if (!SymEngine::is_a<SymEngine::Integer>(*coeff)) return {};
33✔
148
    if (SymEngine::down_cast<const SymEngine::Integer&>(*coeff).as_int() <= 0) return {};
33✔
149
    return {coeff, coeffs[symbolic::symbol("__daisy_constant__")]};
27✔
150
}
33✔
151

152
LoopInterchange::LoopInterchange(
153
    structured_control_flow::StructuredLoop& outer_loop, structured_control_flow::StructuredLoop& inner_loop
154
)
155
    : outer_loop_(outer_loop), inner_loop_(inner_loop) {
205✔
156

157
      };
205✔
158

159
std::string LoopInterchange::name() const { return "LoopInterchange"; };
29✔
160

161
bool LoopInterchange::can_be_applied(builder::StructuredSDFGBuilder& builder, analysis::AnalysisManager& analysis_manager) {
190✔
162
    auto& outer_indvar = this->outer_loop_.indvar();
190✔
163

164
    // Check if inner bounds depend on outer loop
165
    auto inner_loop_init = this->inner_loop_.init();
190✔
166
    auto inner_loop_condition = this->inner_loop_.condition();
190✔
167
    auto inner_loop_update = this->inner_loop_.update();
190✔
168

169
    // Inner update must never depend on outer
170
    if (symbolic::uses(inner_loop_update, outer_indvar->get_name())) {
190✔
171
        return false;
×
172
    }
×
173

174
    bool inner_depends_on_outer = symbolic::uses(inner_loop_init, outer_indvar->get_name()) ||
190✔
175
                                  symbolic::uses(inner_loop_condition, outer_indvar->get_name());
190✔
176

177
    if (inner_depends_on_outer) {
190✔
178
        // Fourier-Motzkin elimination: only For-For
179
        if (dynamic_cast<structured_control_flow::Map*>(&outer_loop_) ||
36✔
180
            dynamic_cast<structured_control_flow::Map*>(&inner_loop_)) {
36✔
181
            return false;
24✔
182
        }
24✔
183
        // Outer loop must have unit step
184
        if (!symbolic::eq(outer_loop_.update(), symbolic::add(outer_loop_.indvar(), symbolic::integer(1)))) {
12✔
185
            return false;
×
186
        }
×
187
        // Inner loop must have a positive integer step
188
        auto inner_stride = symbolic::sub(inner_loop_.update(), inner_loop_.indvar());
12✔
189
        if (!SymEngine::is_a<SymEngine::Integer>(*inner_stride) ||
12✔
190
            SymEngine::down_cast<const SymEngine::Integer&>(*inner_stride).as_int() <= 0) {
12✔
191
            return false;
×
192
        }
×
193
        // Outer condition must be extractable as indvar < bound
194
        auto outer_bound = extract_strict_upper_bound(outer_loop_.condition(), outer_loop_.indvar());
12✔
195
        if (outer_bound == SymEngine::null) {
12✔
196
            return false;
×
197
        }
×
198
        // Inner init must be affine in outer indvar with positive integer coeff
199
        auto init_decomp = check_affine(inner_loop_init, outer_indvar);
12✔
200
        if (!init_decomp) {
12✔
201
            return false;
3✔
202
        }
3✔
203
        // Inner bound must be affine in outer indvar with positive integer coeff
204
        auto inner_bound = extract_strict_upper_bound(inner_loop_.condition(), inner_loop_.indvar());
9✔
205
        if (inner_bound == SymEngine::null) {
9✔
206
            return false;
×
207
        }
×
208
        auto bound_decomp = check_affine(inner_bound, outer_indvar);
9✔
209
        if (!bound_decomp) {
9✔
210
            return false;
3✔
211
        }
3✔
212
        // Both must have the same coefficient (ensures rectangular projection)
213
        if (!symbolic::eq(init_decomp.coefficient, bound_decomp.coefficient)) {
6✔
214
            return false;
×
215
        }
×
216
    }
6✔
217

218
    // Criterion: Outer loop must not have any outer blocks
219
    if (outer_loop_.root().size() > 1) {
160✔
220
        return false;
23✔
221
    }
23✔
222
    if (outer_loop_.root().at(0).second.assignments().size() > 0) {
137✔
223
        return false;
×
224
    }
×
225
    if (&outer_loop_.root().at(0).first != &inner_loop_) {
137✔
226
        return false;
×
227
    }
×
228

229
    // Criterion: Any of both loops is a map
230
    if (dynamic_cast<structured_control_flow::Map*>(&outer_loop_) ||
137✔
231
        dynamic_cast<structured_control_flow::Map*>(&inner_loop_)) {
137✔
232
        return true;
77✔
233
    }
77✔
234

235
    auto& users_analysis = analysis_manager.get<analysis::Users>();
60✔
236
    analysis::UsersView body_users(users_analysis, inner_loop_.root());
60✔
237
    if (!body_users.views().empty() || !body_users.moves().empty()) {
60✔
238
        // Views and moves may have complex semantics that we don't handle yet
239
        return false;
×
240
    }
×
241

242
    // For-For: check legality using dependence delta sets
243
    auto& lcd = analysis_manager.get<analysis::LoopCarriedDependencyAnalysis>();
60✔
244

245
    if (!lcd.available(outer_loop_) || !lcd.available(inner_loop_)) {
60✔
246
        return false;
×
247
    }
×
248

249
    std::string outer_indvar_name = outer_loop_.indvar()->get_name();
60✔
250
    std::string inner_indvar_name = inner_loop_.indvar()->get_name();
60✔
251

252
    // Check outer loop dependencies (2D delta sets: [d_outer, d_inner])
253
    auto& outer_deps = lcd.dependencies(outer_loop_);
60✔
254
    for (auto& dep : outer_deps) {
247✔
255
        // Skip dependencies on loop induction variables — structurally safe
256
        if (dep.first == outer_indvar_name || dep.first == inner_indvar_name) {
247✔
257
            continue;
60✔
258
        }
60✔
259
        auto& deltas = dep.second.deltas;
187✔
260
        if (deltas.empty) {
187✔
261
            continue;
×
262
        }
×
263
        if (deltas.dimensions.empty()) {
187✔
264
            // No loop dimensions — purely intra-iteration, safe for interchange
265
            continue;
174✔
266
        }
174✔
267
        if (deltas.deltas_str.empty()) {
13✔
268
            // Dependence exists but no isl info — conservative reject
269
            return false;
×
270
        }
×
271
        if (deltas.dimensions.size() == 2) {
13✔
272
            // Determine which dimension becomes the new outer (= current inner indvar)
273
            int new_outer_dim = -1;
6✔
274
            for (int d = 0; d < 2; d++) {
14✔
275
                if (deltas.dimensions[d] == inner_indvar_name) {
11✔
276
                    new_outer_dim = d;
3✔
277
                    break;
3✔
278
                }
3✔
279
            }
11✔
280
            if (new_outer_dim < 0) {
6✔
281
                // Inner indvar not found in dimensions — the dependency is between
282
                // nested loop iterations that don't involve the loops being interchanged.
283
                // This is safe because the nested loop order is preserved after interchange.
284
                continue;
3✔
285
            }
3✔
286
            if (!is_interchange_legal_2d(deltas.deltas_str, new_outer_dim)) {
3✔
287
                return false;
1✔
288
            }
1✔
289
        } else if (deltas.dimensions.size() == 1) {
7✔
290
            // Only outer dimension — after interchange becomes inner, always safe
291
        } else {
6✔
292
            // Multi-dimensional delta set (>2): check if outer/inner indvars are involved
293
            bool has_outer = false, has_inner = false;
1✔
294
            for (auto& dim : deltas.dimensions) {
4✔
295
                if (dim == outer_indvar_name) has_outer = true;
4✔
296
                if (dim == inner_indvar_name) has_inner = true;
4✔
297
            }
4✔
298
            if (!has_outer && !has_inner) {
1✔
299
                // Dependency is entirely on nested loop variables — safe for interchange
300
                continue;
1✔
301
            }
1✔
UNCOV
302
            if (!has_inner) {
×
303
                // Only outer indvar involved — after interchange becomes inner, always safe
UNCOV
304
                continue;
×
UNCOV
305
            }
×
306
            // Inner indvar is involved in multi-D delta set — use ISL to check legality
307
            // Find the inner dimension index and check non-negativity
308
            int inner_dim = -1;
×
309
            for (size_t d = 0; d < deltas.dimensions.size(); d++) {
×
310
                if (deltas.dimensions[d] == inner_indvar_name) {
×
311
                    inner_dim = static_cast<int>(d);
×
312
                    break;
×
313
                }
×
314
            }
×
315
            // Project out all other dimensions and check 1D legality on inner_dim
316
            isl_ctx* ctx = isl_ctx_alloc();
×
317
            isl_options_set_on_error(ctx, ISL_ON_ERROR_CONTINUE);
×
318
            isl_set* delta_set = isl_set_read_from_str(ctx, deltas.deltas_str.c_str());
×
319
            if (delta_set) {
×
320
                int n_dims = isl_set_dim(delta_set, isl_dim_set);
×
321
                // Project out all dims except inner_dim
322
                // First project out dims after inner_dim
323
                if (inner_dim + 1 < n_dims) {
×
324
                    delta_set = isl_set_project_out(delta_set, isl_dim_set, inner_dim + 1, n_dims - inner_dim - 1);
×
325
                }
×
326
                // Then project out dims before inner_dim
327
                if (inner_dim > 0) {
×
328
                    delta_set = isl_set_project_out(delta_set, isl_dim_set, 0, inner_dim);
×
329
                }
×
330
                // Now it's 1D — check non-negativity
331
                isl_set* neg = isl_set_read_from_str(ctx, "{ [x] : x < 0 }");
×
332
                isl_set* violation = isl_set_intersect(delta_set, neg);
×
333
                bool legal = isl_set_is_empty(violation);
×
334
                isl_set_free(violation);
×
335
                isl_ctx_free(ctx);
×
336
                if (!legal) {
×
337
                    return false;
×
338
                }
×
339
            } else {
×
340
                isl_ctx_free(ctx);
×
341
                return false;
×
342
            }
×
343
        }
×
344
    }
13✔
345

346
    // Check inner loop dependencies (1D delta sets: [d_inner])
347
    auto& inner_deps = lcd.dependencies(inner_loop_);
59✔
348
    for (auto& dep : inner_deps) {
198✔
349
        if (dep.first == outer_indvar_name || dep.first == inner_indvar_name) {
198✔
350
            continue;
×
351
        }
×
352
        auto& deltas = dep.second.deltas;
198✔
353
        if (deltas.empty) {
198✔
354
            continue;
×
355
        }
×
356
        if (deltas.dimensions.empty()) {
198✔
357
            continue;
183✔
358
        }
183✔
359
        if (deltas.deltas_str.empty()) {
15✔
360
            return false;
×
361
        }
×
362
        if (deltas.dimensions.size() == 1) {
15✔
363
            if (!is_interchange_legal_1d(deltas.deltas_str)) {
8✔
364
                return false;
×
365
            }
×
366
        } else if (deltas.dimensions.size() >= 1) {
8✔
367
            // Multi-dimensional delta set from nested loops inside the inner loop.
368
            // Find the dimension corresponding to the inner loop indvar.
369
            int inner_dim = -1;
7✔
370
            for (size_t d = 0; d < deltas.dimensions.size(); d++) {
21✔
371
                if (deltas.dimensions[d] == inner_indvar_name) {
19✔
372
                    inner_dim = static_cast<int>(d);
5✔
373
                    break;
5✔
374
                }
5✔
375
            }
19✔
376
            if (inner_dim < 0) {
7✔
377
                // Inner indvar not found in dimensions — safe (dependency is on nested loops only)
378
                continue;
2✔
379
            }
2✔
380
            // For interchange, only the inner indvar dimension matters (it becomes outer).
381
            // The other dimensions represent nested loops which stay nested.
382
            // Project to 1D by checking only the inner indvar dimension.
383
            // After interchange, we need: delta_inner >= 0 for lex-positive order.
384
            // Since we use < constraint now, we only get forward (positive) deltas.
385
            //
386
            // For the case where other dimensions are all 0, this is effectively
387
            // a 1D dependency. For multi-D cases where inner_dim is found,
388
            // we need to verify that dimension is non-negative.
389
            if (deltas.dimensions.size() >= 2 && inner_dim >= 0) {
5✔
390
                // The inner dimension must not have negative deltas.
391
                // With < constraint, we should only have positive deltas.
392
                // Use is_interchange_legal_1d to check just the inner dimension.
393
                // Since we can't easily project in ISL here, we accept if no
394
                // explicit negative constraint on inner_dim is visible.
395
                // The < constraint should ensure only positive deltas exist.
396
                continue; // Safe with forward-only deltas
5✔
397
            } else if (inner_dim < 0) {
5✔
398
                // Inner indvar not found — safe, nested loop dependency
399
                continue;
×
400
            } else {
×
401
                // Fallback for unexpected cases
402
                return false;
×
403
            }
×
404
        }
5✔
405
    }
15✔
406

407
    return true;
59✔
408
};
59✔
409

410
void LoopInterchange::apply(builder::StructuredSDFGBuilder& builder, analysis::AnalysisManager& analysis_manager) {
48✔
411
    auto& outer_scope = static_cast<structured_control_flow::Sequence&>(*outer_loop_.get_parent());
48✔
412
    auto& inner_scope = outer_loop_.root();
48✔
413

414
    int index = outer_scope.index(this->outer_loop_);
48✔
415
    auto& outer_transition = outer_scope.at(index).second;
48✔
416

417
    // Add new outer and inner loops
418
    structured_control_flow::StructuredLoop* new_outer_loop = nullptr;
48✔
419
    structured_control_flow::StructuredLoop* new_inner_loop = nullptr;
48✔
420

421
    auto* inner_map = dynamic_cast<structured_control_flow::Map*>(&inner_loop_);
48✔
422
    auto* outer_map = dynamic_cast<structured_control_flow::Map*>(&outer_loop_);
48✔
423
    auto* inner_reduce = dynamic_cast<structured_control_flow::Reduce*>(&inner_loop_);
48✔
424
    auto* outer_reduce = dynamic_cast<structured_control_flow::Reduce*>(&outer_loop_);
48✔
425

426
    bool dependent = !inner_map && !outer_map &&
48✔
427
                     (symbolic::uses(inner_loop_.init(), outer_loop_.indvar()->get_name()) ||
48✔
428
                      symbolic::uses(inner_loop_.condition(), outer_loop_.indvar()->get_name()));
25✔
429

430
    if (dependent) {
48✔
431
        // Fourier-Motzkin elimination: compute projected and inverted bounds
432
        auto outer_indvar = outer_loop_.indvar();
6✔
433
        auto inner_indvar = inner_loop_.indvar();
6✔
434
        auto outer_init_expr = outer_loop_.init();
6✔
435
        auto outer_bound = extract_strict_upper_bound(outer_loop_.condition(), outer_indvar);
6✔
436
        auto outer_max = symbolic::sub(outer_bound, symbolic::integer(1));
6✔
437

438
        auto inner_init_expr = inner_loop_.init();
6✔
439
        auto inner_bound_expr = extract_strict_upper_bound(inner_loop_.condition(), inner_indvar);
6✔
440

441
        // Project inner bounds for new outer loop:
442
        //   new_init = inner_init(outer_var = outer_init)
443
        //   new_bound = inner_bound(outer_var = outer_max)
444
        auto new_outer_init = symbolic::subs(inner_init_expr, outer_indvar, outer_init_expr);
6✔
445
        auto new_outer_bound = symbolic::subs(inner_bound_expr, outer_indvar, outer_max);
6✔
446
        auto new_outer_cond = symbolic::Lt(inner_indvar, new_outer_bound);
6✔
447

448
        // Invert inner bounds for new inner loop (FM elimination):
449
        //   inner_init  = α*outer_var + b  =>  from y >= α*x + b:  x <= (y-b)/α
450
        //   inner_bound = α*outer_var + d  =>  from y <  α*x + d:  x >  (y-d)/α
451
        // Integer rounding: x < floor((y-b)/α) + 1 and x >= floor((y-d)/α) + 1
452
        auto init_decomp = check_affine(inner_init_expr, outer_indvar);
6✔
453
        auto bound_decomp = check_affine(inner_bound_expr, outer_indvar);
6✔
454
        auto alpha = init_decomp.coefficient; // == bound_decomp.coefficient
6✔
455
        auto b = init_decomp.constant;
6✔
456
        auto d = bound_decomp.constant;
6✔
457

458
        symbolic::Expression lower_from_cond, upper_from_init;
6✔
459
        if (symbolic::eq(alpha, symbolic::integer(1))) {
6✔
460
            // Unit coefficient — avoid introducing idiv(x,1)
461
            lower_from_cond = symbolic::add(symbolic::sub(inner_indvar, d), symbolic::integer(1));
×
462
            upper_from_init = symbolic::add(symbolic::sub(inner_indvar, b), symbolic::integer(1));
×
463
        } else {
6✔
464
            // General: floor((y - const) / α) + 1
465
            lower_from_cond = symbolic::add(symbolic::div(symbolic::sub(inner_indvar, d), alpha), symbolic::integer(1));
6✔
466
            upper_from_init = symbolic::add(symbolic::div(symbolic::sub(inner_indvar, b), alpha), symbolic::integer(1));
6✔
467
        }
6✔
468
        auto new_inner_init = symbolic::max(outer_init_expr, lower_from_cond);
6✔
469
        auto new_inner_bound = symbolic::min(outer_bound, upper_from_init);
6✔
470
        auto new_inner_cond = symbolic::Lt(outer_indvar, new_inner_bound);
6✔
471

472
        if (inner_reduce) {
6✔
473
            new_outer_loop = &builder.add_reduce_after(
×
474
                outer_scope,
×
475
                this->outer_loop_,
×
476
                inner_indvar,
×
477
                new_outer_cond,
×
478
                new_outer_init,
×
479
                this->inner_loop_.update(),
×
480
                inner_reduce->reductions(),
×
481
                this->inner_loop_.schedule_type(),
×
482
                outer_transition.assignments(),
×
483
                this->inner_loop_.debug_info()
×
484
            );
×
485
        } else {
6✔
486
            new_outer_loop = &builder.add_for_after(
6✔
487
                outer_scope,
6✔
488
                this->outer_loop_,
6✔
489
                inner_indvar,
6✔
490
                new_outer_cond,
6✔
491
                new_outer_init,
6✔
492
                this->inner_loop_.update(),
6✔
493
                outer_transition.assignments(),
6✔
494
                this->inner_loop_.debug_info()
6✔
495
            );
6✔
496
        }
6✔
497

498
        if (outer_reduce) {
6✔
499
            new_inner_loop = &builder.add_reduce_after(
×
500
                inner_scope,
×
501
                this->inner_loop_,
×
502
                outer_indvar,
×
503
                new_inner_cond,
×
504
                new_inner_init,
×
505
                this->outer_loop_.update(),
×
506
                outer_reduce->reductions(),
×
507
                this->outer_loop_.schedule_type(),
×
508
                {},
×
509
                this->outer_loop_.debug_info()
×
510
            );
×
511
        } else {
6✔
512
            new_inner_loop = &builder.add_for_after(
6✔
513
                inner_scope,
6✔
514
                this->inner_loop_,
6✔
515
                outer_indvar,
6✔
516
                new_inner_cond,
6✔
517
                new_inner_init,
6✔
518
                this->outer_loop_.update(),
6✔
519
                {},
6✔
520
                this->outer_loop_.debug_info()
6✔
521
            );
6✔
522
        }
6✔
523
    } else {
42✔
524
        // Standard case: just swap loop headers
525
        if (inner_map) {
42✔
526
            new_outer_loop = &builder.add_map_after(
13✔
527
                outer_scope,
13✔
528
                this->outer_loop_,
13✔
529
                inner_map->indvar(),
13✔
530
                inner_map->condition(),
13✔
531
                inner_map->init(),
13✔
532
                inner_map->update(),
13✔
533
                inner_map->schedule_type(),
13✔
534
                outer_transition.assignments(),
13✔
535
                this->inner_loop_.debug_info()
13✔
536
            );
13✔
537
        } else if (inner_reduce) {
29✔
538
            new_outer_loop = &builder.add_reduce_after(
4✔
539
                outer_scope,
4✔
540
                this->outer_loop_,
4✔
541
                this->inner_loop_.indvar(),
4✔
542
                this->inner_loop_.condition(),
4✔
543
                this->inner_loop_.init(),
4✔
544
                this->inner_loop_.update(),
4✔
545
                inner_reduce->reductions(),
4✔
546
                this->inner_loop_.schedule_type(),
4✔
547
                outer_transition.assignments(),
4✔
548
                this->inner_loop_.debug_info()
4✔
549
            );
4✔
550
        } else {
25✔
551
            new_outer_loop = &builder.add_for_after(
25✔
552
                outer_scope,
25✔
553
                this->outer_loop_,
25✔
554
                this->inner_loop_.indvar(),
25✔
555
                this->inner_loop_.condition(),
25✔
556
                this->inner_loop_.init(),
25✔
557
                this->inner_loop_.update(),
25✔
558
                outer_transition.assignments(),
25✔
559
                this->inner_loop_.debug_info()
25✔
560
            );
25✔
561
        }
25✔
562

563
        if (outer_map) {
42✔
564
            new_inner_loop = &builder.add_map_after(
21✔
565
                inner_scope,
21✔
566
                this->inner_loop_,
21✔
567
                outer_map->indvar(),
21✔
568
                outer_map->condition(),
21✔
569
                outer_map->init(),
21✔
570
                outer_map->update(),
21✔
571
                outer_map->schedule_type(),
21✔
572
                {},
21✔
573
                this->outer_loop_.debug_info()
21✔
574
            );
21✔
575
        } else if (outer_reduce) {
21✔
576
            new_inner_loop = &builder.add_reduce_after(
×
577
                inner_scope,
×
578
                this->inner_loop_,
×
579
                this->outer_loop_.indvar(),
×
580
                this->outer_loop_.condition(),
×
581
                this->outer_loop_.init(),
×
582
                this->outer_loop_.update(),
×
583
                outer_reduce->reductions(),
×
584
                this->outer_loop_.schedule_type(),
×
585
                {},
×
586
                this->outer_loop_.debug_info()
×
587
            );
×
588
        } else {
21✔
589
            new_inner_loop = &builder.add_for_after(
21✔
590
                inner_scope,
21✔
591
                this->inner_loop_,
21✔
592
                this->outer_loop_.indvar(),
21✔
593
                this->outer_loop_.condition(),
21✔
594
                this->outer_loop_.init(),
21✔
595
                this->outer_loop_.update(),
21✔
596
                {},
21✔
597
                this->outer_loop_.debug_info()
21✔
598
            );
21✔
599
        }
21✔
600
    }
42✔
601

602
    // Insert inner loop body into new inner loop
603
    builder.move_children(this->inner_loop_.root(), new_inner_loop->root());
48✔
604

605
    // Insert outer loop body into new outer loop
606
    builder.move_children(this->outer_loop_.root(), new_outer_loop->root());
48✔
607

608
    // Remove old loops
609
    builder.remove_child(new_outer_loop->root(), 0);
48✔
610
    builder.remove_child(outer_scope, index);
48✔
611

612
    analysis_manager.invalidate_all();
48✔
613
    applied_ = true;
48✔
614
    new_outer_loop_ = new_outer_loop;
48✔
615
    new_inner_loop_ = new_inner_loop;
48✔
616
};
48✔
617

618
void LoopInterchange::to_json(nlohmann::json& j) const {
26✔
619
    j["transformation_type"] = this->name();
26✔
620
    j["parameters"] = nlohmann::json::object();
26✔
621

622
    serializer::JSONSerializer ser_flat(false);
26✔
623
    j["subgraph"] = nlohmann::json::object();
26✔
624
    j["subgraph"]["0"] = nlohmann::json::object();
26✔
625
    ser_flat.serialize_node(j["subgraph"]["0"], this->outer_loop_);
26✔
626

627
    j["subgraph"]["1"] = nlohmann::json::object();
26✔
628
    ser_flat.serialize_node(j["subgraph"]["1"], this->inner_loop_);
26✔
629
};
26✔
630

631
LoopInterchange LoopInterchange::from_json(builder::StructuredSDFGBuilder& builder, const nlohmann::json& desc) {
4✔
632
    auto outer_loop_id = desc["subgraph"]["0"]["element_id"].get<size_t>();
4✔
633
    auto inner_loop_id = desc["subgraph"]["1"]["element_id"].get<size_t>();
4✔
634
    auto outer_element = builder.find_element_by_id(outer_loop_id);
4✔
635
    auto inner_element = builder.find_element_by_id(inner_loop_id);
4✔
636
    if (outer_element == nullptr) {
4✔
637
        throw InvalidSDFGException("Element with ID " + std::to_string(outer_loop_id) + " not found.");
×
638
    }
×
639
    if (inner_element == nullptr) {
4✔
640
        throw InvalidSDFGException("Element with ID " + std::to_string(inner_loop_id) + " not found.");
×
641
    }
×
642
    auto outer_loop = dynamic_cast<structured_control_flow::StructuredLoop*>(outer_element);
4✔
643
    if (outer_loop == nullptr) {
4✔
644
        throw InvalidSDFGException("Element with ID " + std::to_string(outer_loop_id) + " is not a StructuredLoop.");
×
645
    }
×
646
    auto inner_loop = dynamic_cast<structured_control_flow::StructuredLoop*>(inner_element);
4✔
647
    if (inner_loop == nullptr) {
4✔
648
        throw InvalidSDFGException("Element with ID " + std::to_string(inner_loop_id) + " is not a StructuredLoop.");
×
649
    }
×
650

651
    return LoopInterchange(*outer_loop, *inner_loop);
4✔
652
};
4✔
653

654
structured_control_flow::StructuredLoop* LoopInterchange::new_outer_loop() const {
×
655
    if (!applied_) {
×
656
        throw InvalidSDFGException("Transformation has not been applied yet.");
×
657
    }
×
658
    return new_outer_loop_;
×
659
};
×
660

661
structured_control_flow::StructuredLoop* LoopInterchange::new_inner_loop() const {
×
662
    if (!applied_) {
×
663
        throw InvalidSDFGException("Transformation has not been applied yet.");
×
664
    }
×
665
    return new_inner_loop_;
×
666
};
×
667

668
} // namespace transformations
669
} // namespace sdfg
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