2 * Copyright 2005-2007 Universiteit Leiden
3 * Copyright 2008-2009 Katholieke Universiteit Leuven
4 * Copyright 2010 INRIA Saclay
5 * Copyright 2012 Universiteit Leiden
6 * Copyright 2014 Ecole Normale Superieure
8 * Use of this software is governed by the MIT license
10 * Written by Sven Verdoolaege, Leiden Institute of Advanced Computer Science,
11 * Universiteit Leiden, Niels Bohrweg 1, 2333 CA Leiden, The Netherlands
12 * and K.U.Leuven, Departement Computerwetenschappen, Celestijnenlaan 200A,
13 * B-3001 Leuven, Belgium
14 * and INRIA Saclay - Ile-de-France, Parc Club Orsay Universite,
15 * ZAC des vignes, 4 rue Jacques Monod, 91893 Orsay, France
16 * and Ecole Normale Superieure, 45 rue d'Ulm, 75230 Paris, France
21 #include <isl/union_set.h>
22 #include <isl/union_map.h>
24 #include <isl/schedule_node.h>
26 #include <isl/stream.h>
28 enum isl_restriction_type
{
29 isl_restriction_type_empty
,
30 isl_restriction_type_none
,
31 isl_restriction_type_input
,
32 isl_restriction_type_output
35 struct isl_restriction
{
36 enum isl_restriction_type type
;
42 /* Create a restriction of the given type.
44 static __isl_give isl_restriction
*isl_restriction_alloc(
45 __isl_take isl_map
*source_map
, enum isl_restriction_type type
)
48 isl_restriction
*restr
;
53 ctx
= isl_map_get_ctx(source_map
);
54 restr
= isl_calloc_type(ctx
, struct isl_restriction
);
60 isl_map_free(source_map
);
63 isl_map_free(source_map
);
67 /* Create a restriction that doesn't restrict anything.
69 __isl_give isl_restriction
*isl_restriction_none(__isl_take isl_map
*source_map
)
71 return isl_restriction_alloc(source_map
, isl_restriction_type_none
);
74 /* Create a restriction that removes everything.
76 __isl_give isl_restriction
*isl_restriction_empty(
77 __isl_take isl_map
*source_map
)
79 return isl_restriction_alloc(source_map
, isl_restriction_type_empty
);
82 /* Create a restriction on the input of the maximization problem
83 * based on the given source and sink restrictions.
85 __isl_give isl_restriction
*isl_restriction_input(
86 __isl_take isl_set
*source_restr
, __isl_take isl_set
*sink_restr
)
89 isl_restriction
*restr
;
91 if (!source_restr
|| !sink_restr
)
94 ctx
= isl_set_get_ctx(source_restr
);
95 restr
= isl_calloc_type(ctx
, struct isl_restriction
);
99 restr
->type
= isl_restriction_type_input
;
100 restr
->source
= source_restr
;
101 restr
->sink
= sink_restr
;
105 isl_set_free(source_restr
);
106 isl_set_free(sink_restr
);
110 /* Create a restriction on the output of the maximization problem
111 * based on the given source restriction.
113 __isl_give isl_restriction
*isl_restriction_output(
114 __isl_take isl_set
*source_restr
)
117 isl_restriction
*restr
;
122 ctx
= isl_set_get_ctx(source_restr
);
123 restr
= isl_calloc_type(ctx
, struct isl_restriction
);
127 restr
->type
= isl_restriction_type_output
;
128 restr
->source
= source_restr
;
132 isl_set_free(source_restr
);
136 __isl_null isl_restriction
*isl_restriction_free(
137 __isl_take isl_restriction
*restr
)
142 isl_set_free(restr
->source
);
143 isl_set_free(restr
->sink
);
148 isl_ctx
*isl_restriction_get_ctx(__isl_keep isl_restriction
*restr
)
150 return restr
? isl_set_get_ctx(restr
->source
) : NULL
;
153 /* A private structure to keep track of a mapping together with
154 * a user-specified identifier and a boolean indicating whether
155 * the map represents a must or may access/dependence.
157 struct isl_labeled_map
{
163 /* A structure containing the input for dependence analysis:
165 * - n_must + n_may (<= max_source) sources
166 * - a function for determining the relative order of sources and sink
167 * The must sources are placed before the may sources.
169 * domain_map is an auxiliary map that maps the sink access relation
170 * to the domain of this access relation.
171 * This field is only needed when restrict_fn is set and
172 * the field itself is set by isl_access_info_compute_flow.
174 * restrict_fn is a callback that (if not NULL) will be called
175 * right before any lexicographical maximization.
177 struct isl_access_info
{
179 struct isl_labeled_map sink
;
180 isl_access_level_before level_before
;
182 isl_access_restrict restrict_fn
;
188 struct isl_labeled_map source
[1];
191 /* A structure containing the output of dependence analysis:
192 * - n_source dependences
193 * - a wrapped subset of the sink for which definitely no source could be found
194 * - a wrapped subset of the sink for which possibly no source could be found
197 isl_set
*must_no_source
;
198 isl_set
*may_no_source
;
200 struct isl_labeled_map
*dep
;
203 /* Construct an isl_access_info structure and fill it up with
204 * the given data. The number of sources is set to 0.
206 __isl_give isl_access_info
*isl_access_info_alloc(__isl_take isl_map
*sink
,
207 void *sink_user
, isl_access_level_before fn
, int max_source
)
210 struct isl_access_info
*acc
;
215 ctx
= isl_map_get_ctx(sink
);
216 isl_assert(ctx
, max_source
>= 0, goto error
);
218 acc
= isl_calloc(ctx
, struct isl_access_info
,
219 sizeof(struct isl_access_info
) +
220 (max_source
- 1) * sizeof(struct isl_labeled_map
));
224 acc
->sink
.map
= sink
;
225 acc
->sink
.data
= sink_user
;
226 acc
->level_before
= fn
;
227 acc
->max_source
= max_source
;
237 /* Free the given isl_access_info structure.
239 __isl_null isl_access_info
*isl_access_info_free(
240 __isl_take isl_access_info
*acc
)
246 isl_map_free(acc
->domain_map
);
247 isl_map_free(acc
->sink
.map
);
248 for (i
= 0; i
< acc
->n_must
+ acc
->n_may
; ++i
)
249 isl_map_free(acc
->source
[i
].map
);
254 isl_ctx
*isl_access_info_get_ctx(__isl_keep isl_access_info
*acc
)
256 return acc
? isl_map_get_ctx(acc
->sink
.map
) : NULL
;
259 __isl_give isl_access_info
*isl_access_info_set_restrict(
260 __isl_take isl_access_info
*acc
, isl_access_restrict fn
, void *user
)
264 acc
->restrict_fn
= fn
;
265 acc
->restrict_user
= user
;
269 /* Add another source to an isl_access_info structure, making
270 * sure the "must" sources are placed before the "may" sources.
271 * This function may be called at most max_source times on a
272 * given isl_access_info structure, with max_source as specified
273 * in the call to isl_access_info_alloc that constructed the structure.
275 __isl_give isl_access_info
*isl_access_info_add_source(
276 __isl_take isl_access_info
*acc
, __isl_take isl_map
*source
,
277 int must
, void *source_user
)
283 ctx
= isl_map_get_ctx(acc
->sink
.map
);
284 isl_assert(ctx
, acc
->n_must
+ acc
->n_may
< acc
->max_source
, goto error
);
288 acc
->source
[acc
->n_must
+ acc
->n_may
] =
289 acc
->source
[acc
->n_must
];
290 acc
->source
[acc
->n_must
].map
= source
;
291 acc
->source
[acc
->n_must
].data
= source_user
;
292 acc
->source
[acc
->n_must
].must
= 1;
295 acc
->source
[acc
->n_must
+ acc
->n_may
].map
= source
;
296 acc
->source
[acc
->n_must
+ acc
->n_may
].data
= source_user
;
297 acc
->source
[acc
->n_must
+ acc
->n_may
].must
= 0;
303 isl_map_free(source
);
304 isl_access_info_free(acc
);
308 /* Return -n, 0 or n (with n a positive value), depending on whether
309 * the source access identified by p1 should be sorted before, together
310 * or after that identified by p2.
312 * If p1 appears before p2, then it should be sorted first.
313 * For more generic initial schedules, it is possible that neither
314 * p1 nor p2 appears before the other, or at least not in any obvious way.
315 * We therefore also check if p2 appears before p1, in which case p2
316 * should be sorted first.
317 * If not, we try to order the two statements based on the description
318 * of the iteration domains. This results in an arbitrary, but fairly
321 static int access_sort_cmp(const void *p1
, const void *p2
, void *user
)
323 isl_access_info
*acc
= user
;
324 const struct isl_labeled_map
*i1
, *i2
;
327 i1
= (const struct isl_labeled_map
*) p1
;
328 i2
= (const struct isl_labeled_map
*) p2
;
330 level1
= acc
->level_before(i1
->data
, i2
->data
);
334 level2
= acc
->level_before(i2
->data
, i1
->data
);
338 h1
= isl_map_get_hash(i1
->map
);
339 h2
= isl_map_get_hash(i2
->map
);
340 return h1
> h2
? 1 : h1
< h2
? -1 : 0;
343 /* Sort the must source accesses in their textual order.
345 static __isl_give isl_access_info
*isl_access_info_sort_sources(
346 __isl_take isl_access_info
*acc
)
350 if (acc
->n_must
<= 1)
353 if (isl_sort(acc
->source
, acc
->n_must
, sizeof(struct isl_labeled_map
),
354 access_sort_cmp
, acc
) < 0)
355 return isl_access_info_free(acc
);
360 /* Align the parameters of the two spaces if needed and then call
363 static __isl_give isl_space
*space_align_and_join(__isl_take isl_space
*left
,
364 __isl_take isl_space
*right
)
366 isl_bool equal_params
;
368 equal_params
= isl_space_has_equal_params(left
, right
);
369 if (equal_params
< 0)
372 return isl_space_join(left
, right
);
374 left
= isl_space_align_params(left
, isl_space_copy(right
));
375 right
= isl_space_align_params(right
, isl_space_copy(left
));
376 return isl_space_join(left
, right
);
378 isl_space_free(left
);
379 isl_space_free(right
);
383 /* Initialize an empty isl_flow structure corresponding to a given
384 * isl_access_info structure.
385 * For each must access, two dependences are created (initialized
386 * to the empty relation), one for the resulting must dependences
387 * and one for the resulting may dependences. May accesses can
388 * only lead to may dependences, so only one dependence is created
390 * This function is private as isl_flow structures are only supposed
391 * to be created by isl_access_info_compute_flow.
393 static __isl_give isl_flow
*isl_flow_alloc(__isl_keep isl_access_info
*acc
)
397 struct isl_flow
*dep
;
402 ctx
= isl_map_get_ctx(acc
->sink
.map
);
403 dep
= isl_calloc_type(ctx
, struct isl_flow
);
407 n
= 2 * acc
->n_must
+ acc
->n_may
;
408 dep
->dep
= isl_calloc_array(ctx
, struct isl_labeled_map
, n
);
413 for (i
= 0; i
< acc
->n_must
; ++i
) {
415 dim
= space_align_and_join(
416 isl_map_get_space(acc
->source
[i
].map
),
417 isl_space_reverse(isl_map_get_space(acc
->sink
.map
)));
418 dep
->dep
[2 * i
].map
= isl_map_empty(dim
);
419 dep
->dep
[2 * i
+ 1].map
= isl_map_copy(dep
->dep
[2 * i
].map
);
420 dep
->dep
[2 * i
].data
= acc
->source
[i
].data
;
421 dep
->dep
[2 * i
+ 1].data
= acc
->source
[i
].data
;
422 dep
->dep
[2 * i
].must
= 1;
423 dep
->dep
[2 * i
+ 1].must
= 0;
424 if (!dep
->dep
[2 * i
].map
|| !dep
->dep
[2 * i
+ 1].map
)
427 for (i
= acc
->n_must
; i
< acc
->n_must
+ acc
->n_may
; ++i
) {
429 dim
= space_align_and_join(
430 isl_map_get_space(acc
->source
[i
].map
),
431 isl_space_reverse(isl_map_get_space(acc
->sink
.map
)));
432 dep
->dep
[acc
->n_must
+ i
].map
= isl_map_empty(dim
);
433 dep
->dep
[acc
->n_must
+ i
].data
= acc
->source
[i
].data
;
434 dep
->dep
[acc
->n_must
+ i
].must
= 0;
435 if (!dep
->dep
[acc
->n_must
+ i
].map
)
445 /* Iterate over all sources and for each resulting flow dependence
446 * that is not empty, call the user specfied function.
447 * The second argument in this function call identifies the source,
448 * while the third argument correspond to the final argument of
449 * the isl_flow_foreach call.
451 isl_stat
isl_flow_foreach(__isl_keep isl_flow
*deps
,
452 isl_stat (*fn
)(__isl_take isl_map
*dep
, int must
, void *dep_user
,
459 return isl_stat_error
;
461 for (i
= 0; i
< deps
->n_source
; ++i
) {
462 if (isl_map_plain_is_empty(deps
->dep
[i
].map
))
464 if (fn(isl_map_copy(deps
->dep
[i
].map
), deps
->dep
[i
].must
,
465 deps
->dep
[i
].data
, user
) < 0)
466 return isl_stat_error
;
472 /* Return a copy of the subset of the sink for which no source could be found.
474 __isl_give isl_map
*isl_flow_get_no_source(__isl_keep isl_flow
*deps
, int must
)
480 return isl_set_unwrap(isl_set_copy(deps
->must_no_source
));
482 return isl_set_unwrap(isl_set_copy(deps
->may_no_source
));
485 void isl_flow_free(__isl_take isl_flow
*deps
)
491 isl_set_free(deps
->must_no_source
);
492 isl_set_free(deps
->may_no_source
);
494 for (i
= 0; i
< deps
->n_source
; ++i
)
495 isl_map_free(deps
->dep
[i
].map
);
501 isl_ctx
*isl_flow_get_ctx(__isl_keep isl_flow
*deps
)
503 return deps
? isl_set_get_ctx(deps
->must_no_source
) : NULL
;
506 /* Return a map that enforces that the domain iteration occurs after
507 * the range iteration at the given level.
508 * If level is odd, then the domain iteration should occur after
509 * the target iteration in their shared level/2 outermost loops.
510 * In this case we simply need to enforce that these outermost
511 * loop iterations are the same.
512 * If level is even, then the loop iterator of the domain should
513 * be greater than the loop iterator of the range at the last
514 * of the level/2 shared loops, i.e., loop level/2 - 1.
516 static __isl_give isl_map
*after_at_level(__isl_take isl_space
*dim
, int level
)
518 struct isl_basic_map
*bmap
;
521 bmap
= isl_basic_map_equal(dim
, level
/2);
523 bmap
= isl_basic_map_more_at(dim
, level
/2 - 1);
525 return isl_map_from_basic_map(bmap
);
528 /* Compute the partial lexicographic maximum of "dep" on domain "sink",
529 * but first check if the user has set acc->restrict_fn and if so
530 * update either the input or the output of the maximization problem
531 * with respect to the resulting restriction.
533 * Since the user expects a mapping from sink iterations to source iterations,
534 * whereas the domain of "dep" is a wrapped map, mapping sink iterations
535 * to accessed array elements, we first need to project out the accessed
536 * sink array elements by applying acc->domain_map.
537 * Similarly, the sink restriction specified by the user needs to be
538 * converted back to the wrapped map.
540 static __isl_give isl_map
*restricted_partial_lexmax(
541 __isl_keep isl_access_info
*acc
, __isl_take isl_map
*dep
,
542 int source
, __isl_take isl_set
*sink
, __isl_give isl_set
**empty
)
545 isl_restriction
*restr
;
546 isl_set
*sink_domain
;
550 if (!acc
->restrict_fn
)
551 return isl_map_partial_lexmax(dep
, sink
, empty
);
553 source_map
= isl_map_copy(dep
);
554 source_map
= isl_map_apply_domain(source_map
,
555 isl_map_copy(acc
->domain_map
));
556 sink_domain
= isl_set_copy(sink
);
557 sink_domain
= isl_set_apply(sink_domain
, isl_map_copy(acc
->domain_map
));
558 restr
= acc
->restrict_fn(source_map
, sink_domain
,
559 acc
->source
[source
].data
, acc
->restrict_user
);
560 isl_set_free(sink_domain
);
561 isl_map_free(source_map
);
565 if (restr
->type
== isl_restriction_type_input
) {
566 dep
= isl_map_intersect_range(dep
, isl_set_copy(restr
->source
));
567 sink_restr
= isl_set_copy(restr
->sink
);
568 sink_restr
= isl_set_apply(sink_restr
,
569 isl_map_reverse(isl_map_copy(acc
->domain_map
)));
570 sink
= isl_set_intersect(sink
, sink_restr
);
571 } else if (restr
->type
== isl_restriction_type_empty
) {
572 isl_space
*space
= isl_map_get_space(dep
);
574 dep
= isl_map_empty(space
);
577 res
= isl_map_partial_lexmax(dep
, sink
, empty
);
579 if (restr
->type
== isl_restriction_type_output
)
580 res
= isl_map_intersect_range(res
, isl_set_copy(restr
->source
));
582 isl_restriction_free(restr
);
591 /* Compute the last iteration of must source j that precedes the sink
592 * at the given level for sink iterations in set_C.
593 * The subset of set_C for which no such iteration can be found is returned
596 static struct isl_map
*last_source(struct isl_access_info
*acc
,
597 struct isl_set
*set_C
,
598 int j
, int level
, struct isl_set
**empty
)
600 struct isl_map
*read_map
;
601 struct isl_map
*write_map
;
602 struct isl_map
*dep_map
;
603 struct isl_map
*after
;
604 struct isl_map
*result
;
606 read_map
= isl_map_copy(acc
->sink
.map
);
607 write_map
= isl_map_copy(acc
->source
[j
].map
);
608 write_map
= isl_map_reverse(write_map
);
609 dep_map
= isl_map_apply_range(read_map
, write_map
);
610 after
= after_at_level(isl_map_get_space(dep_map
), level
);
611 dep_map
= isl_map_intersect(dep_map
, after
);
612 result
= restricted_partial_lexmax(acc
, dep_map
, j
, set_C
, empty
);
613 result
= isl_map_reverse(result
);
618 /* For a given mapping between iterations of must source j and iterations
619 * of the sink, compute the last iteration of must source k preceding
620 * the sink at level before_level for any of the sink iterations,
621 * but following the corresponding iteration of must source j at level
624 static struct isl_map
*last_later_source(struct isl_access_info
*acc
,
625 struct isl_map
*old_map
,
626 int j
, int before_level
,
627 int k
, int after_level
,
628 struct isl_set
**empty
)
631 struct isl_set
*set_C
;
632 struct isl_map
*read_map
;
633 struct isl_map
*write_map
;
634 struct isl_map
*dep_map
;
635 struct isl_map
*after_write
;
636 struct isl_map
*before_read
;
637 struct isl_map
*result
;
639 set_C
= isl_map_range(isl_map_copy(old_map
));
640 read_map
= isl_map_copy(acc
->sink
.map
);
641 write_map
= isl_map_copy(acc
->source
[k
].map
);
643 write_map
= isl_map_reverse(write_map
);
644 dep_map
= isl_map_apply_range(read_map
, write_map
);
645 dim
= space_align_and_join(isl_map_get_space(acc
->source
[k
].map
),
646 isl_space_reverse(isl_map_get_space(acc
->source
[j
].map
)));
647 after_write
= after_at_level(dim
, after_level
);
648 after_write
= isl_map_apply_range(after_write
, old_map
);
649 after_write
= isl_map_reverse(after_write
);
650 dep_map
= isl_map_intersect(dep_map
, after_write
);
651 before_read
= after_at_level(isl_map_get_space(dep_map
), before_level
);
652 dep_map
= isl_map_intersect(dep_map
, before_read
);
653 result
= restricted_partial_lexmax(acc
, dep_map
, k
, set_C
, empty
);
654 result
= isl_map_reverse(result
);
659 /* Given a shared_level between two accesses, return 1 if the
660 * the first can precede the second at the requested target_level.
661 * If the target level is odd, i.e., refers to a statement level
662 * dimension, then first needs to precede second at the requested
663 * level, i.e., shared_level must be equal to target_level.
664 * If the target level is odd, then the two loops should share
665 * at least the requested number of outer loops.
667 static int can_precede_at_level(int shared_level
, int target_level
)
669 if (shared_level
< target_level
)
671 if ((target_level
% 2) && shared_level
> target_level
)
676 /* Given a possible flow dependence temp_rel[j] between source j and the sink
677 * at level sink_level, remove those elements for which
678 * there is an iteration of another source k < j that is closer to the sink.
679 * The flow dependences temp_rel[k] are updated with the improved sources.
680 * Any improved source needs to precede the sink at the same level
681 * and needs to follow source j at the same or a deeper level.
682 * The lower this level, the later the execution date of source k.
683 * We therefore consider lower levels first.
685 * If temp_rel[j] is empty, then there can be no improvement and
686 * we return immediately.
688 static int intermediate_sources(__isl_keep isl_access_info
*acc
,
689 struct isl_map
**temp_rel
, int j
, int sink_level
)
692 int depth
= 2 * isl_map_dim(acc
->source
[j
].map
, isl_dim_in
) + 1;
694 if (isl_map_plain_is_empty(temp_rel
[j
]))
697 for (k
= j
- 1; k
>= 0; --k
) {
699 plevel
= acc
->level_before(acc
->source
[k
].data
, acc
->sink
.data
);
700 if (!can_precede_at_level(plevel
, sink_level
))
703 plevel2
= acc
->level_before(acc
->source
[j
].data
,
704 acc
->source
[k
].data
);
706 for (level
= sink_level
; level
<= depth
; ++level
) {
708 struct isl_set
*trest
;
709 struct isl_map
*copy
;
711 if (!can_precede_at_level(plevel2
, level
))
714 copy
= isl_map_copy(temp_rel
[j
]);
715 T
= last_later_source(acc
, copy
, j
, sink_level
, k
,
717 if (isl_map_plain_is_empty(T
)) {
722 temp_rel
[j
] = isl_map_intersect_range(temp_rel
[j
], trest
);
723 temp_rel
[k
] = isl_map_union_disjoint(temp_rel
[k
], T
);
730 /* Compute all iterations of may source j that precedes the sink at the given
731 * level for sink iterations in set_C.
733 static __isl_give isl_map
*all_sources(__isl_keep isl_access_info
*acc
,
734 __isl_take isl_set
*set_C
, int j
, int level
)
741 read_map
= isl_map_copy(acc
->sink
.map
);
742 read_map
= isl_map_intersect_domain(read_map
, set_C
);
743 write_map
= isl_map_copy(acc
->source
[acc
->n_must
+ j
].map
);
744 write_map
= isl_map_reverse(write_map
);
745 dep_map
= isl_map_apply_range(read_map
, write_map
);
746 after
= after_at_level(isl_map_get_space(dep_map
), level
);
747 dep_map
= isl_map_intersect(dep_map
, after
);
749 return isl_map_reverse(dep_map
);
752 /* For a given mapping between iterations of must source k and iterations
753 * of the sink, compute all iterations of may source j preceding
754 * the sink at level before_level for any of the sink iterations,
755 * but following the corresponding iteration of must source k at level
758 static __isl_give isl_map
*all_later_sources(__isl_keep isl_access_info
*acc
,
759 __isl_take isl_map
*old_map
,
760 int j
, int before_level
, int k
, int after_level
)
767 isl_map
*after_write
;
768 isl_map
*before_read
;
770 set_C
= isl_map_range(isl_map_copy(old_map
));
771 read_map
= isl_map_copy(acc
->sink
.map
);
772 read_map
= isl_map_intersect_domain(read_map
, set_C
);
773 write_map
= isl_map_copy(acc
->source
[acc
->n_must
+ j
].map
);
775 write_map
= isl_map_reverse(write_map
);
776 dep_map
= isl_map_apply_range(read_map
, write_map
);
777 dim
= isl_space_join(isl_map_get_space(acc
->source
[acc
->n_must
+ j
].map
),
778 isl_space_reverse(isl_map_get_space(acc
->source
[k
].map
)));
779 after_write
= after_at_level(dim
, after_level
);
780 after_write
= isl_map_apply_range(after_write
, old_map
);
781 after_write
= isl_map_reverse(after_write
);
782 dep_map
= isl_map_intersect(dep_map
, after_write
);
783 before_read
= after_at_level(isl_map_get_space(dep_map
), before_level
);
784 dep_map
= isl_map_intersect(dep_map
, before_read
);
785 return isl_map_reverse(dep_map
);
788 /* Given the must and may dependence relations for the must accesses
789 * for level sink_level, check if there are any accesses of may access j
790 * that occur in between and return their union.
791 * If some of these accesses are intermediate with respect to
792 * (previously thought to be) must dependences, then these
793 * must dependences are turned into may dependences.
795 static __isl_give isl_map
*all_intermediate_sources(
796 __isl_keep isl_access_info
*acc
, __isl_take isl_map
*map
,
797 struct isl_map
**must_rel
, struct isl_map
**may_rel
,
798 int j
, int sink_level
)
801 int depth
= 2 * isl_map_dim(acc
->source
[acc
->n_must
+ j
].map
,
804 for (k
= 0; k
< acc
->n_must
; ++k
) {
807 if (isl_map_plain_is_empty(may_rel
[k
]) &&
808 isl_map_plain_is_empty(must_rel
[k
]))
811 plevel
= acc
->level_before(acc
->source
[k
].data
,
812 acc
->source
[acc
->n_must
+ j
].data
);
814 for (level
= sink_level
; level
<= depth
; ++level
) {
819 if (!can_precede_at_level(plevel
, level
))
822 copy
= isl_map_copy(may_rel
[k
]);
823 T
= all_later_sources(acc
, copy
, j
, sink_level
, k
, level
);
824 map
= isl_map_union(map
, T
);
826 copy
= isl_map_copy(must_rel
[k
]);
827 T
= all_later_sources(acc
, copy
, j
, sink_level
, k
, level
);
828 ran
= isl_map_range(isl_map_copy(T
));
829 map
= isl_map_union(map
, T
);
830 may_rel
[k
] = isl_map_union_disjoint(may_rel
[k
],
831 isl_map_intersect_range(isl_map_copy(must_rel
[k
]),
833 T
= isl_map_from_domain_and_range(
835 isl_space_domain(isl_map_get_space(must_rel
[k
]))),
837 must_rel
[k
] = isl_map_subtract(must_rel
[k
], T
);
844 /* Compute dependences for the case where all accesses are "may"
845 * accesses, which boils down to computing memory based dependences.
846 * The generic algorithm would also work in this case, but it would
847 * be overkill to use it.
849 static __isl_give isl_flow
*compute_mem_based_dependences(
850 __isl_keep isl_access_info
*acc
)
857 res
= isl_flow_alloc(acc
);
861 mustdo
= isl_map_domain(isl_map_copy(acc
->sink
.map
));
862 maydo
= isl_set_copy(mustdo
);
864 for (i
= 0; i
< acc
->n_may
; ++i
) {
871 plevel
= acc
->level_before(acc
->source
[i
].data
, acc
->sink
.data
);
872 is_before
= plevel
& 1;
875 dim
= isl_map_get_space(res
->dep
[i
].map
);
877 before
= isl_map_lex_le_first(dim
, plevel
);
879 before
= isl_map_lex_lt_first(dim
, plevel
);
880 dep
= isl_map_apply_range(isl_map_copy(acc
->source
[i
].map
),
881 isl_map_reverse(isl_map_copy(acc
->sink
.map
)));
882 dep
= isl_map_intersect(dep
, before
);
883 mustdo
= isl_set_subtract(mustdo
,
884 isl_map_range(isl_map_copy(dep
)));
885 res
->dep
[i
].map
= isl_map_union(res
->dep
[i
].map
, dep
);
888 res
->may_no_source
= isl_set_subtract(maydo
, isl_set_copy(mustdo
));
889 res
->must_no_source
= mustdo
;
894 /* Compute dependences for the case where there is at least one
897 * The core algorithm considers all levels in which a source may precede
898 * the sink, where a level may either be a statement level or a loop level.
899 * The outermost statement level is 1, the first loop level is 2, etc...
900 * The algorithm basically does the following:
901 * for all levels l of the read access from innermost to outermost
902 * for all sources w that may precede the sink access at that level
903 * compute the last iteration of the source that precedes the sink access
905 * add result to possible last accesses at level l of source w
906 * for all sources w2 that we haven't considered yet at this level that may
907 * also precede the sink access
908 * for all levels l2 of w from l to innermost
909 * for all possible last accesses dep of w at l
910 * compute last iteration of w2 between the source and sink
912 * add result to possible last accesses at level l of write w2
913 * and replace possible last accesses dep by the remainder
916 * The above algorithm is applied to the must access. During the course
917 * of the algorithm, we keep track of sink iterations that still
918 * need to be considered. These iterations are split into those that
919 * haven't been matched to any source access (mustdo) and those that have only
920 * been matched to may accesses (maydo).
921 * At the end of each level, we also consider the may accesses.
922 * In particular, we consider may accesses that precede the remaining
923 * sink iterations, moving elements from mustdo to maydo when appropriate,
924 * and may accesses that occur between a must source and a sink of any
925 * dependences found at the current level, turning must dependences into
926 * may dependences when appropriate.
929 static __isl_give isl_flow
*compute_val_based_dependences(
930 __isl_keep isl_access_info
*acc
)
934 isl_set
*mustdo
= NULL
;
935 isl_set
*maydo
= NULL
;
938 isl_map
**must_rel
= NULL
;
939 isl_map
**may_rel
= NULL
;
944 res
= isl_flow_alloc(acc
);
947 ctx
= isl_map_get_ctx(acc
->sink
.map
);
949 depth
= 2 * isl_map_dim(acc
->sink
.map
, isl_dim_in
) + 1;
950 mustdo
= isl_map_domain(isl_map_copy(acc
->sink
.map
));
951 maydo
= isl_set_empty(isl_set_get_space(mustdo
));
952 if (!mustdo
|| !maydo
)
954 if (isl_set_plain_is_empty(mustdo
))
957 must_rel
= isl_alloc_array(ctx
, struct isl_map
*, acc
->n_must
);
958 may_rel
= isl_alloc_array(ctx
, struct isl_map
*, acc
->n_must
);
959 if (!must_rel
|| !may_rel
)
962 for (level
= depth
; level
>= 1; --level
) {
963 for (j
= acc
->n_must
-1; j
>=0; --j
) {
965 space
= isl_map_get_space(res
->dep
[2 * j
].map
);
966 must_rel
[j
] = isl_map_empty(space
);
967 may_rel
[j
] = isl_map_copy(must_rel
[j
]);
970 for (j
= acc
->n_must
- 1; j
>= 0; --j
) {
972 struct isl_set
*rest
;
975 plevel
= acc
->level_before(acc
->source
[j
].data
,
977 if (!can_precede_at_level(plevel
, level
))
980 T
= last_source(acc
, mustdo
, j
, level
, &rest
);
981 must_rel
[j
] = isl_map_union_disjoint(must_rel
[j
], T
);
984 intermediate_sources(acc
, must_rel
, j
, level
);
986 T
= last_source(acc
, maydo
, j
, level
, &rest
);
987 may_rel
[j
] = isl_map_union_disjoint(may_rel
[j
], T
);
990 intermediate_sources(acc
, may_rel
, j
, level
);
992 if (isl_set_plain_is_empty(mustdo
) &&
993 isl_set_plain_is_empty(maydo
))
996 for (j
= j
- 1; j
>= 0; --j
) {
999 plevel
= acc
->level_before(acc
->source
[j
].data
,
1001 if (!can_precede_at_level(plevel
, level
))
1004 intermediate_sources(acc
, must_rel
, j
, level
);
1005 intermediate_sources(acc
, may_rel
, j
, level
);
1008 for (j
= 0; j
< acc
->n_may
; ++j
) {
1013 plevel
= acc
->level_before(acc
->source
[acc
->n_must
+ j
].data
,
1015 if (!can_precede_at_level(plevel
, level
))
1018 T
= all_sources(acc
, isl_set_copy(maydo
), j
, level
);
1019 res
->dep
[2 * acc
->n_must
+ j
].map
=
1020 isl_map_union(res
->dep
[2 * acc
->n_must
+ j
].map
, T
);
1021 T
= all_sources(acc
, isl_set_copy(mustdo
), j
, level
);
1022 ran
= isl_map_range(isl_map_copy(T
));
1023 res
->dep
[2 * acc
->n_must
+ j
].map
=
1024 isl_map_union(res
->dep
[2 * acc
->n_must
+ j
].map
, T
);
1025 mustdo
= isl_set_subtract(mustdo
, isl_set_copy(ran
));
1026 maydo
= isl_set_union_disjoint(maydo
, ran
);
1028 T
= res
->dep
[2 * acc
->n_must
+ j
].map
;
1029 T
= all_intermediate_sources(acc
, T
, must_rel
, may_rel
,
1031 res
->dep
[2 * acc
->n_must
+ j
].map
= T
;
1034 for (j
= acc
->n_must
- 1; j
>= 0; --j
) {
1035 res
->dep
[2 * j
].map
=
1036 isl_map_union_disjoint(res
->dep
[2 * j
].map
,
1038 res
->dep
[2 * j
+ 1].map
=
1039 isl_map_union_disjoint(res
->dep
[2 * j
+ 1].map
,
1043 if (isl_set_plain_is_empty(mustdo
) &&
1044 isl_set_plain_is_empty(maydo
))
1051 res
->must_no_source
= mustdo
;
1052 res
->may_no_source
= maydo
;
1056 isl_set_free(mustdo
);
1057 isl_set_free(maydo
);
1063 /* Given a "sink" access, a list of n "source" accesses,
1064 * compute for each iteration of the sink access
1065 * and for each element accessed by that iteration,
1066 * the source access in the list that last accessed the
1067 * element accessed by the sink access before this sink access.
1068 * Each access is given as a map from the loop iterators
1069 * to the array indices.
1070 * The result is a list of n relations between source and sink
1071 * iterations and a subset of the domain of the sink access,
1072 * corresponding to those iterations that access an element
1073 * not previously accessed.
1075 * To deal with multi-valued sink access relations, the sink iteration
1076 * domain is first extended with dimensions that correspond to the data
1077 * space. However, these extra dimensions are not projected out again.
1078 * It is up to the caller to decide whether these dimensions should be kept.
1080 static __isl_give isl_flow
*access_info_compute_flow_core(
1081 __isl_take isl_access_info
*acc
)
1083 struct isl_flow
*res
= NULL
;
1088 acc
->sink
.map
= isl_map_range_map(acc
->sink
.map
);
1092 if (acc
->n_must
== 0)
1093 res
= compute_mem_based_dependences(acc
);
1095 acc
= isl_access_info_sort_sources(acc
);
1096 res
= compute_val_based_dependences(acc
);
1098 acc
= isl_access_info_free(acc
);
1101 if (!res
->must_no_source
|| !res
->may_no_source
)
1105 isl_access_info_free(acc
);
1110 /* Given a "sink" access, a list of n "source" accesses,
1111 * compute for each iteration of the sink access
1112 * and for each element accessed by that iteration,
1113 * the source access in the list that last accessed the
1114 * element accessed by the sink access before this sink access.
1115 * Each access is given as a map from the loop iterators
1116 * to the array indices.
1117 * The result is a list of n relations between source and sink
1118 * iterations and a subset of the domain of the sink access,
1119 * corresponding to those iterations that access an element
1120 * not previously accessed.
1122 * To deal with multi-valued sink access relations,
1123 * access_info_compute_flow_core extends the sink iteration domain
1124 * with dimensions that correspond to the data space. These extra dimensions
1125 * are projected out from the result of access_info_compute_flow_core.
1127 __isl_give isl_flow
*isl_access_info_compute_flow(__isl_take isl_access_info
*acc
)
1130 struct isl_flow
*res
;
1135 acc
->domain_map
= isl_map_domain_map(isl_map_copy(acc
->sink
.map
));
1136 res
= access_info_compute_flow_core(acc
);
1140 for (j
= 0; j
< res
->n_source
; ++j
) {
1141 res
->dep
[j
].map
= isl_map_range_factor_domain(res
->dep
[j
].map
);
1142 if (!res
->dep
[j
].map
)
1153 /* Keep track of some information about a schedule for a given
1154 * access. In particular, keep track of which dimensions
1155 * have a constant value and of the actual constant values.
1157 struct isl_sched_info
{
1162 static void sched_info_free(__isl_take
struct isl_sched_info
*info
)
1166 isl_vec_free(info
->cst
);
1171 /* Extract information on the constant dimensions of the schedule
1172 * for a given access. The "map" is of the form
1176 * with S the schedule domain, D the iteration domain and A the data domain.
1178 static __isl_give
struct isl_sched_info
*sched_info_alloc(
1179 __isl_keep isl_map
*map
)
1183 struct isl_sched_info
*info
;
1189 dim
= isl_space_unwrap(isl_space_domain(isl_map_get_space(map
)));
1192 n
= isl_space_dim(dim
, isl_dim_in
);
1193 isl_space_free(dim
);
1195 ctx
= isl_map_get_ctx(map
);
1196 info
= isl_alloc_type(ctx
, struct isl_sched_info
);
1199 info
->is_cst
= isl_alloc_array(ctx
, int, n
);
1200 info
->cst
= isl_vec_alloc(ctx
, n
);
1201 if (n
&& (!info
->is_cst
|| !info
->cst
))
1204 for (i
= 0; i
< n
; ++i
) {
1207 v
= isl_map_plain_get_val_if_fixed(map
, isl_dim_in
, i
);
1210 info
->is_cst
[i
] = !isl_val_is_nan(v
);
1211 if (info
->is_cst
[i
])
1212 info
->cst
= isl_vec_set_element_val(info
->cst
, i
, v
);
1219 sched_info_free(info
);
1223 /* The different types of access relations that isl_union_access_info
1226 * "isl_access_sink" represents the sink accesses.
1227 * "isl_access_must_source" represents the definite source accesses.
1228 * "isl_access_may_source" represents the possible source accesses.
1230 * isl_access_sink is sometimes treated differently and
1231 * should therefore appear first.
1233 enum isl_access_type
{
1235 isl_access_must_source
,
1236 isl_access_may_source
,
1240 /* This structure represents the input for a dependence analysis computation.
1242 * "access" contains the access relations.
1244 * "schedule" or "schedule_map" represents the execution order.
1245 * Exactly one of these fields should be NULL. The other field
1246 * determines the execution order.
1248 * The domains of these four maps refer to the same iteration spaces(s).
1249 * The ranges of the first three maps also refer to the same data space(s).
1251 * After a call to isl_union_access_info_introduce_schedule,
1252 * the "schedule_map" field no longer contains useful information.
1254 struct isl_union_access_info
{
1255 isl_union_map
*access
[isl_access_end
];
1257 isl_schedule
*schedule
;
1258 isl_union_map
*schedule_map
;
1261 /* Free "access" and return NULL.
1263 __isl_null isl_union_access_info
*isl_union_access_info_free(
1264 __isl_take isl_union_access_info
*access
)
1266 enum isl_access_type i
;
1271 for (i
= isl_access_sink
; i
< isl_access_end
; ++i
)
1272 isl_union_map_free(access
->access
[i
]);
1273 isl_schedule_free(access
->schedule
);
1274 isl_union_map_free(access
->schedule_map
);
1280 /* Return the isl_ctx to which "access" belongs.
1282 isl_ctx
*isl_union_access_info_get_ctx(__isl_keep isl_union_access_info
*access
)
1286 return isl_union_map_get_ctx(access
->access
[isl_access_sink
]);
1289 /* Construct an empty (invalid) isl_union_access_info object.
1290 * The caller is responsible for setting the sink access relation and
1291 * initializing all the other fields, e.g., by calling
1292 * isl_union_access_info_init.
1294 static __isl_give isl_union_access_info
*isl_union_access_info_alloc(
1297 return isl_calloc_type(ctx
, isl_union_access_info
);
1300 /* Initialize all the fields of "info", except the sink access relation,
1301 * which is assumed to have been set by the caller.
1303 * By default, we use the schedule field of the isl_union_access_info,
1304 * but this may be overridden by a call
1305 * to isl_union_access_info_set_schedule_map.
1307 static __isl_give isl_union_access_info
*isl_union_access_info_init(
1308 __isl_take isl_union_access_info
*info
)
1311 isl_union_map
*empty
;
1312 enum isl_access_type i
;
1316 if (!info
->access
[isl_access_sink
])
1317 return isl_union_access_info_free(info
);
1319 space
= isl_union_map_get_space(info
->access
[isl_access_sink
]);
1320 empty
= isl_union_map_empty(isl_space_copy(space
));
1321 for (i
= isl_access_sink
+ 1; i
< isl_access_end
; ++i
)
1322 if (!info
->access
[i
])
1323 info
->access
[i
] = isl_union_map_copy(empty
);
1324 isl_union_map_free(empty
);
1325 if (!info
->schedule
&& !info
->schedule_map
)
1326 info
->schedule
= isl_schedule_empty(isl_space_copy(space
));
1327 isl_space_free(space
);
1329 for (i
= isl_access_sink
+ 1; i
< isl_access_end
; ++i
)
1330 if (!info
->access
[i
])
1331 return isl_union_access_info_free(info
);
1332 if (!info
->schedule
&& !info
->schedule_map
)
1333 return isl_union_access_info_free(info
);
1338 /* Create a new isl_union_access_info with the given sink accesses and
1339 * and no other accesses or schedule information.
1341 __isl_give isl_union_access_info
*isl_union_access_info_from_sink(
1342 __isl_take isl_union_map
*sink
)
1345 isl_union_access_info
*access
;
1349 ctx
= isl_union_map_get_ctx(sink
);
1350 access
= isl_union_access_info_alloc(ctx
);
1353 access
->access
[isl_access_sink
] = sink
;
1354 return isl_union_access_info_init(access
);
1356 isl_union_map_free(sink
);
1360 /* Replace the access relation of type "type" of "info" by "access".
1362 static __isl_give isl_union_access_info
*isl_union_access_info_set(
1363 __isl_take isl_union_access_info
*info
,
1364 enum isl_access_type type
, __isl_take isl_union_map
*access
)
1366 if (!info
|| !access
)
1369 isl_union_map_free(info
->access
[type
]);
1370 info
->access
[type
] = access
;
1374 isl_union_access_info_free(info
);
1375 isl_union_map_free(access
);
1379 /* Replace the definite source accesses of "access" by "must_source".
1381 __isl_give isl_union_access_info
*isl_union_access_info_set_must_source(
1382 __isl_take isl_union_access_info
*access
,
1383 __isl_take isl_union_map
*must_source
)
1385 return isl_union_access_info_set(access
, isl_access_must_source
,
1389 /* Replace the possible source accesses of "access" by "may_source".
1391 __isl_give isl_union_access_info
*isl_union_access_info_set_may_source(
1392 __isl_take isl_union_access_info
*access
,
1393 __isl_take isl_union_map
*may_source
)
1395 return isl_union_access_info_set(access
, isl_access_may_source
,
1399 /* Replace the schedule of "access" by "schedule".
1400 * Also free the schedule_map in case it was set last.
1402 __isl_give isl_union_access_info
*isl_union_access_info_set_schedule(
1403 __isl_take isl_union_access_info
*access
,
1404 __isl_take isl_schedule
*schedule
)
1406 if (!access
|| !schedule
)
1409 access
->schedule_map
= isl_union_map_free(access
->schedule_map
);
1410 isl_schedule_free(access
->schedule
);
1411 access
->schedule
= schedule
;
1415 isl_union_access_info_free(access
);
1416 isl_schedule_free(schedule
);
1420 /* Replace the schedule map of "access" by "schedule_map".
1421 * Also free the schedule in case it was set last.
1423 __isl_give isl_union_access_info
*isl_union_access_info_set_schedule_map(
1424 __isl_take isl_union_access_info
*access
,
1425 __isl_take isl_union_map
*schedule_map
)
1427 if (!access
|| !schedule_map
)
1430 isl_union_map_free(access
->schedule_map
);
1431 access
->schedule
= isl_schedule_free(access
->schedule
);
1432 access
->schedule_map
= schedule_map
;
1436 isl_union_access_info_free(access
);
1437 isl_union_map_free(schedule_map
);
1441 __isl_give isl_union_access_info
*isl_union_access_info_copy(
1442 __isl_keep isl_union_access_info
*access
)
1444 isl_union_access_info
*copy
;
1445 enum isl_access_type i
;
1449 copy
= isl_union_access_info_from_sink(
1450 isl_union_map_copy(access
->access
[isl_access_sink
]));
1451 for (i
= isl_access_sink
+ 1; i
< isl_access_end
; ++i
)
1452 copy
= isl_union_access_info_set(copy
, i
,
1453 isl_union_map_copy(access
->access
[i
]));
1454 if (access
->schedule
)
1455 copy
= isl_union_access_info_set_schedule(copy
,
1456 isl_schedule_copy(access
->schedule
));
1458 copy
= isl_union_access_info_set_schedule_map(copy
,
1459 isl_union_map_copy(access
->schedule_map
));
1464 /* Print a key-value pair of a YAML mapping to "p",
1465 * with key "name" and value "umap".
1467 static __isl_give isl_printer
*print_union_map_field(__isl_take isl_printer
*p
,
1468 const char *name
, __isl_keep isl_union_map
*umap
)
1470 p
= isl_printer_print_str(p
, name
);
1471 p
= isl_printer_yaml_next(p
);
1472 p
= isl_printer_print_str(p
, "\"");
1473 p
= isl_printer_print_union_map(p
, umap
);
1474 p
= isl_printer_print_str(p
, "\"");
1475 p
= isl_printer_yaml_next(p
);
1480 /* An enumeration of the various keys that may appear in a YAML mapping
1481 * of an isl_union_access_info object.
1482 * The keys for the access relation types are assumed to have the same values
1483 * as the access relation types in isl_access_type.
1486 isl_ai_key_error
= -1,
1487 isl_ai_key_sink
= isl_access_sink
,
1488 isl_ai_key_must_source
= isl_access_must_source
,
1489 isl_ai_key_may_source
= isl_access_may_source
,
1490 isl_ai_key_schedule_map
,
1491 isl_ai_key_schedule
,
1495 /* Textual representations of the YAML keys for an isl_union_access_info
1498 static char *key_str
[] = {
1499 [isl_ai_key_sink
] = "sink",
1500 [isl_ai_key_must_source
] = "must_source",
1501 [isl_ai_key_may_source
] = "may_source",
1502 [isl_ai_key_schedule_map
] = "schedule_map",
1503 [isl_ai_key_schedule
] = "schedule",
1506 /* Print a key-value pair corresponding to the access relation of type "type"
1507 * of a YAML mapping of "info" to "p".
1509 * The sink access relation is always printed, but any other access relation
1510 * is only printed if it is non-empty.
1512 static __isl_give isl_printer
*print_access_field(__isl_take isl_printer
*p
,
1513 __isl_keep isl_union_access_info
*info
, enum isl_access_type type
)
1515 if (type
!= isl_access_sink
) {
1518 empty
= isl_union_map_is_empty(info
->access
[type
]);
1520 return isl_printer_free(p
);
1524 return print_union_map_field(p
, key_str
[type
], info
->access
[type
]);
1527 /* Print the information contained in "access" to "p".
1528 * The information is printed as a YAML document.
1530 __isl_give isl_printer
*isl_printer_print_union_access_info(
1531 __isl_take isl_printer
*p
, __isl_keep isl_union_access_info
*access
)
1533 enum isl_access_type i
;
1536 return isl_printer_free(p
);
1538 p
= isl_printer_yaml_start_mapping(p
);
1539 for (i
= isl_access_sink
; i
< isl_access_end
; ++i
)
1540 p
= print_access_field(p
, access
, i
);
1541 if (access
->schedule
) {
1542 p
= isl_printer_print_str(p
, key_str
[isl_ai_key_schedule
]);
1543 p
= isl_printer_yaml_next(p
);
1544 p
= isl_printer_print_schedule(p
, access
->schedule
);
1545 p
= isl_printer_yaml_next(p
);
1547 p
= print_union_map_field(p
, key_str
[isl_ai_key_schedule_map
],
1548 access
->schedule_map
);
1550 p
= isl_printer_yaml_end_mapping(p
);
1555 /* Return a string representation of the information in "access".
1556 * The information is printed in flow format.
1558 __isl_give
char *isl_union_access_info_to_str(
1559 __isl_keep isl_union_access_info
*access
)
1567 p
= isl_printer_to_str(isl_union_access_info_get_ctx(access
));
1568 p
= isl_printer_set_yaml_style(p
, ISL_YAML_STYLE_FLOW
);
1569 p
= isl_printer_print_union_access_info(p
, access
);
1570 s
= isl_printer_get_str(p
);
1571 isl_printer_free(p
);
1577 #define KEY enum isl_ai_key
1579 #define KEY_ERROR isl_ai_key_error
1581 #define KEY_END isl_ai_key_end
1582 #include "extract_key.c"
1585 #define BASE union_map
1586 #include "read_in_string_templ.c"
1588 /* Read an isl_union_access_info object from "s".
1590 * Start off with an empty (invalid) isl_union_access_info object and
1591 * then fill up the fields based on the input.
1592 * The input needs to contain at least a description of the sink
1593 * access relation as well as some form of schedule.
1594 * The other access relations are set to empty relations
1595 * by isl_union_access_info_init if they are not specified in the input.
1597 __isl_give isl_union_access_info
*isl_stream_read_union_access_info(
1601 isl_union_access_info
*info
;
1604 int schedule_set
= 0;
1606 if (isl_stream_yaml_read_start_mapping(s
))
1609 ctx
= isl_stream_get_ctx(s
);
1610 info
= isl_union_access_info_alloc(ctx
);
1611 while ((more
= isl_stream_yaml_next(s
)) > 0) {
1612 enum isl_ai_key key
;
1613 isl_union_map
*access
, *schedule_map
;
1614 isl_schedule
*schedule
;
1617 if (isl_stream_yaml_next(s
) < 0)
1618 return isl_union_access_info_free(info
);
1620 case isl_ai_key_end
:
1621 case isl_ai_key_error
:
1622 return isl_union_access_info_free(info
);
1623 case isl_ai_key_sink
:
1625 case isl_ai_key_must_source
:
1626 case isl_ai_key_may_source
:
1627 access
= read_union_map(s
);
1628 info
= isl_union_access_info_set(info
, key
, access
);
1632 case isl_ai_key_schedule_map
:
1634 schedule_map
= read_union_map(s
);
1635 info
= isl_union_access_info_set_schedule_map(info
,
1640 case isl_ai_key_schedule
:
1642 schedule
= isl_stream_read_schedule(s
);
1643 info
= isl_union_access_info_set_schedule(info
,
1651 return isl_union_access_info_free(info
);
1653 if (isl_stream_yaml_read_end_mapping(s
) < 0) {
1654 isl_stream_error(s
, NULL
, "unexpected extra elements");
1655 return isl_union_access_info_free(info
);
1659 isl_stream_error(s
, NULL
, "no sink specified");
1660 return isl_union_access_info_free(info
);
1663 if (!schedule_set
) {
1664 isl_stream_error(s
, NULL
, "no schedule specified");
1665 return isl_union_access_info_free(info
);
1668 return isl_union_access_info_init(info
);
1671 /* Read an isl_union_access_info object from the file "input".
1673 __isl_give isl_union_access_info
*isl_union_access_info_read_from_file(
1674 isl_ctx
*ctx
, FILE *input
)
1677 isl_union_access_info
*access
;
1679 s
= isl_stream_new_file(ctx
, input
);
1682 access
= isl_stream_read_union_access_info(s
);
1688 /* Update the fields of "access" such that they all have the same parameters,
1689 * keeping in mind that the schedule_map field may be NULL and ignoring
1690 * the schedule field.
1692 static __isl_give isl_union_access_info
*isl_union_access_info_align_params(
1693 __isl_take isl_union_access_info
*access
)
1696 enum isl_access_type i
;
1701 space
= isl_union_map_get_space(access
->access
[isl_access_sink
]);
1702 for (i
= isl_access_sink
+ 1; i
< isl_access_end
; ++i
)
1703 space
= isl_space_align_params(space
,
1704 isl_union_map_get_space(access
->access
[i
]));
1705 if (access
->schedule_map
)
1706 space
= isl_space_align_params(space
,
1707 isl_union_map_get_space(access
->schedule_map
));
1708 for (i
= isl_access_sink
; i
< isl_access_end
; ++i
)
1710 isl_union_map_align_params(access
->access
[i
],
1711 isl_space_copy(space
));
1712 if (!access
->schedule_map
) {
1713 isl_space_free(space
);
1715 access
->schedule_map
=
1716 isl_union_map_align_params(access
->schedule_map
, space
);
1717 if (!access
->schedule_map
)
1718 return isl_union_access_info_free(access
);
1721 for (i
= isl_access_sink
; i
< isl_access_end
; ++i
)
1722 if (!access
->access
[i
])
1723 return isl_union_access_info_free(access
);
1728 /* Prepend the schedule dimensions to the iteration domains.
1730 * That is, if the schedule is of the form
1734 * while the access relations are of the form
1738 * then the updated access relations are of the form
1742 * The schedule map is also replaced by the map
1746 * that is used during the internal computation.
1747 * Neither the original schedule map nor this updated schedule map
1748 * are used after the call to this function.
1750 static __isl_give isl_union_access_info
*
1751 isl_union_access_info_introduce_schedule(
1752 __isl_take isl_union_access_info
*access
)
1755 enum isl_access_type i
;
1760 sm
= isl_union_map_reverse(access
->schedule_map
);
1761 sm
= isl_union_map_range_map(sm
);
1762 for (i
= isl_access_sink
; i
< isl_access_end
; ++i
)
1764 isl_union_map_apply_range(isl_union_map_copy(sm
),
1766 access
->schedule_map
= sm
;
1768 for (i
= isl_access_sink
; i
< isl_access_end
; ++i
)
1769 if (!access
->access
[i
])
1770 return isl_union_access_info_free(access
);
1771 if (!access
->schedule_map
)
1772 return isl_union_access_info_free(access
);
1777 /* This structure represents the result of a dependence analysis computation.
1779 * "must_dep" represents the full definite dependences
1780 * "may_dep" represents the full non-definite dependences.
1781 * Both are of the form
1783 * [Source] -> [[Sink -> Data]]
1785 * (after the schedule dimensions have been projected out).
1786 * "must_no_source" represents the subset of the sink accesses for which
1787 * definitely no source was found.
1788 * "may_no_source" represents the subset of the sink accesses for which
1789 * possibly, but not definitely, no source was found.
1791 struct isl_union_flow
{
1792 isl_union_map
*must_dep
;
1793 isl_union_map
*may_dep
;
1794 isl_union_map
*must_no_source
;
1795 isl_union_map
*may_no_source
;
1798 /* Return the isl_ctx to which "flow" belongs.
1800 isl_ctx
*isl_union_flow_get_ctx(__isl_keep isl_union_flow
*flow
)
1802 return flow
? isl_union_map_get_ctx(flow
->must_dep
) : NULL
;
1805 /* Free "flow" and return NULL.
1807 __isl_null isl_union_flow
*isl_union_flow_free(__isl_take isl_union_flow
*flow
)
1811 isl_union_map_free(flow
->must_dep
);
1812 isl_union_map_free(flow
->may_dep
);
1813 isl_union_map_free(flow
->must_no_source
);
1814 isl_union_map_free(flow
->may_no_source
);
1819 void isl_union_flow_dump(__isl_keep isl_union_flow
*flow
)
1824 fprintf(stderr
, "must dependences: ");
1825 isl_union_map_dump(flow
->must_dep
);
1826 fprintf(stderr
, "may dependences: ");
1827 isl_union_map_dump(flow
->may_dep
);
1828 fprintf(stderr
, "must no source: ");
1829 isl_union_map_dump(flow
->must_no_source
);
1830 fprintf(stderr
, "may no source: ");
1831 isl_union_map_dump(flow
->may_no_source
);
1834 /* Return the full definite dependences in "flow", with accessed elements.
1836 __isl_give isl_union_map
*isl_union_flow_get_full_must_dependence(
1837 __isl_keep isl_union_flow
*flow
)
1841 return isl_union_map_copy(flow
->must_dep
);
1844 /* Return the full possible dependences in "flow", including the definite
1845 * dependences, with accessed elements.
1847 __isl_give isl_union_map
*isl_union_flow_get_full_may_dependence(
1848 __isl_keep isl_union_flow
*flow
)
1852 return isl_union_map_union(isl_union_map_copy(flow
->must_dep
),
1853 isl_union_map_copy(flow
->may_dep
));
1856 /* Return the definite dependences in "flow", without the accessed elements.
1858 __isl_give isl_union_map
*isl_union_flow_get_must_dependence(
1859 __isl_keep isl_union_flow
*flow
)
1865 dep
= isl_union_map_copy(flow
->must_dep
);
1866 return isl_union_map_range_factor_domain(dep
);
1869 /* Return the possible dependences in "flow", including the definite
1870 * dependences, without the accessed elements.
1872 __isl_give isl_union_map
*isl_union_flow_get_may_dependence(
1873 __isl_keep isl_union_flow
*flow
)
1879 dep
= isl_union_map_union(isl_union_map_copy(flow
->must_dep
),
1880 isl_union_map_copy(flow
->may_dep
));
1881 return isl_union_map_range_factor_domain(dep
);
1884 /* Return the non-definite dependences in "flow".
1886 static __isl_give isl_union_map
*isl_union_flow_get_non_must_dependence(
1887 __isl_keep isl_union_flow
*flow
)
1891 return isl_union_map_copy(flow
->may_dep
);
1894 /* Return the subset of the sink accesses for which definitely
1895 * no source was found.
1897 __isl_give isl_union_map
*isl_union_flow_get_must_no_source(
1898 __isl_keep isl_union_flow
*flow
)
1902 return isl_union_map_copy(flow
->must_no_source
);
1905 /* Return the subset of the sink accesses for which possibly
1906 * no source was found, including those for which definitely
1907 * no source was found.
1909 __isl_give isl_union_map
*isl_union_flow_get_may_no_source(
1910 __isl_keep isl_union_flow
*flow
)
1914 return isl_union_map_union(isl_union_map_copy(flow
->must_no_source
),
1915 isl_union_map_copy(flow
->may_no_source
));
1918 /* Return the subset of the sink accesses for which possibly, but not
1919 * definitely, no source was found.
1921 static __isl_give isl_union_map
*isl_union_flow_get_non_must_no_source(
1922 __isl_keep isl_union_flow
*flow
)
1926 return isl_union_map_copy(flow
->may_no_source
);
1929 /* Create a new isl_union_flow object, initialized with empty
1930 * dependence relations and sink subsets.
1932 static __isl_give isl_union_flow
*isl_union_flow_alloc(
1933 __isl_take isl_space
*space
)
1936 isl_union_map
*empty
;
1937 isl_union_flow
*flow
;
1941 ctx
= isl_space_get_ctx(space
);
1942 flow
= isl_alloc_type(ctx
, isl_union_flow
);
1946 empty
= isl_union_map_empty(space
);
1947 flow
->must_dep
= isl_union_map_copy(empty
);
1948 flow
->may_dep
= isl_union_map_copy(empty
);
1949 flow
->must_no_source
= isl_union_map_copy(empty
);
1950 flow
->may_no_source
= empty
;
1952 if (!flow
->must_dep
|| !flow
->may_dep
||
1953 !flow
->must_no_source
|| !flow
->may_no_source
)
1954 return isl_union_flow_free(flow
);
1958 isl_space_free(space
);
1962 /* Copy this isl_union_flow object.
1964 __isl_give isl_union_flow
*isl_union_flow_copy(__isl_keep isl_union_flow
*flow
)
1966 isl_union_flow
*copy
;
1971 copy
= isl_union_flow_alloc(isl_union_map_get_space(flow
->must_dep
));
1976 copy
->must_dep
= isl_union_map_union(copy
->must_dep
,
1977 isl_union_map_copy(flow
->must_dep
));
1978 copy
->may_dep
= isl_union_map_union(copy
->may_dep
,
1979 isl_union_map_copy(flow
->may_dep
));
1980 copy
->must_no_source
= isl_union_map_union(copy
->must_no_source
,
1981 isl_union_map_copy(flow
->must_no_source
));
1982 copy
->may_no_source
= isl_union_map_union(copy
->may_no_source
,
1983 isl_union_map_copy(flow
->may_no_source
));
1985 if (!copy
->must_dep
|| !copy
->may_dep
||
1986 !copy
->must_no_source
|| !copy
->may_no_source
)
1987 return isl_union_flow_free(copy
);
1992 /* Drop the schedule dimensions from the iteration domains in "flow".
1993 * In particular, the schedule dimensions have been prepended
1994 * to the iteration domains prior to the dependence analysis by
1995 * replacing the iteration domain D, by the wrapped map [S -> D].
1996 * Replace these wrapped maps by the original D.
1998 * In particular, the dependences computed by access_info_compute_flow_core
2001 * [S -> D] -> [[S' -> D'] -> A]
2003 * The schedule dimensions are projected out by first currying the range,
2006 * [S -> D] -> [S' -> [D' -> A]]
2008 * and then computing the factor range
2012 static __isl_give isl_union_flow
*isl_union_flow_drop_schedule(
2013 __isl_take isl_union_flow
*flow
)
2018 flow
->must_dep
= isl_union_map_range_curry(flow
->must_dep
);
2019 flow
->must_dep
= isl_union_map_factor_range(flow
->must_dep
);
2020 flow
->may_dep
= isl_union_map_range_curry(flow
->may_dep
);
2021 flow
->may_dep
= isl_union_map_factor_range(flow
->may_dep
);
2022 flow
->must_no_source
=
2023 isl_union_map_domain_factor_range(flow
->must_no_source
);
2024 flow
->may_no_source
=
2025 isl_union_map_domain_factor_range(flow
->may_no_source
);
2027 if (!flow
->must_dep
|| !flow
->may_dep
||
2028 !flow
->must_no_source
|| !flow
->may_no_source
)
2029 return isl_union_flow_free(flow
);
2034 struct isl_compute_flow_data
{
2035 isl_union_map
*must_source
;
2036 isl_union_map
*may_source
;
2037 isl_union_flow
*flow
;
2042 struct isl_sched_info
*sink_info
;
2043 struct isl_sched_info
**source_info
;
2044 isl_access_info
*accesses
;
2047 static isl_stat
count_matching_array(__isl_take isl_map
*map
, void *user
)
2051 struct isl_compute_flow_data
*data
;
2053 data
= (struct isl_compute_flow_data
*)user
;
2055 dim
= isl_space_range(isl_map_get_space(map
));
2057 eq
= isl_space_is_equal(dim
, data
->dim
);
2059 isl_space_free(dim
);
2063 return isl_stat_error
;
2070 static isl_stat
collect_matching_array(__isl_take isl_map
*map
, void *user
)
2074 struct isl_sched_info
*info
;
2075 struct isl_compute_flow_data
*data
;
2077 data
= (struct isl_compute_flow_data
*)user
;
2079 dim
= isl_space_range(isl_map_get_space(map
));
2081 eq
= isl_space_is_equal(dim
, data
->dim
);
2083 isl_space_free(dim
);
2092 info
= sched_info_alloc(map
);
2093 data
->source_info
[data
->count
] = info
;
2095 data
->accesses
= isl_access_info_add_source(data
->accesses
,
2096 map
, data
->must
, info
);
2103 return isl_stat_error
;
2106 /* Determine the shared nesting level and the "textual order" of
2107 * the given accesses.
2109 * We first determine the minimal schedule dimension for both accesses.
2111 * If among those dimensions, we can find one where both have a fixed
2112 * value and if moreover those values are different, then the previous
2113 * dimension is the last shared nesting level and the textual order
2114 * is determined based on the order of the fixed values.
2115 * If no such fixed values can be found, then we set the shared
2116 * nesting level to the minimal schedule dimension, with no textual ordering.
2118 static int before(void *first
, void *second
)
2120 struct isl_sched_info
*info1
= first
;
2121 struct isl_sched_info
*info2
= second
;
2125 n1
= isl_vec_size(info1
->cst
);
2126 n2
= isl_vec_size(info2
->cst
);
2131 for (i
= 0; i
< n1
; ++i
) {
2135 if (!info1
->is_cst
[i
])
2137 if (!info2
->is_cst
[i
])
2139 cmp
= isl_vec_cmp_element(info1
->cst
, info2
->cst
, i
);
2143 r
= 2 * i
+ (cmp
< 0);
2151 /* Given a sink access, look for all the source accesses that access
2152 * the same array and perform dataflow analysis on them using
2153 * isl_access_info_compute_flow_core.
2155 static isl_stat
compute_flow(__isl_take isl_map
*map
, void *user
)
2159 struct isl_compute_flow_data
*data
;
2163 data
= (struct isl_compute_flow_data
*)user
;
2166 ctx
= isl_map_get_ctx(map
);
2168 data
->accesses
= NULL
;
2169 data
->sink_info
= NULL
;
2170 data
->source_info
= NULL
;
2172 data
->dim
= isl_space_range(isl_map_get_space(map
));
2174 if (isl_union_map_foreach_map(data
->must_source
,
2175 &count_matching_array
, data
) < 0)
2177 if (isl_union_map_foreach_map(data
->may_source
,
2178 &count_matching_array
, data
) < 0)
2181 data
->sink_info
= sched_info_alloc(map
);
2182 data
->source_info
= isl_calloc_array(ctx
, struct isl_sched_info
*,
2185 data
->accesses
= isl_access_info_alloc(isl_map_copy(map
),
2186 data
->sink_info
, &before
, data
->count
);
2187 if (!data
->sink_info
|| (data
->count
&& !data
->source_info
) ||
2192 if (isl_union_map_foreach_map(data
->must_source
,
2193 &collect_matching_array
, data
) < 0)
2196 if (isl_union_map_foreach_map(data
->may_source
,
2197 &collect_matching_array
, data
) < 0)
2200 flow
= access_info_compute_flow_core(data
->accesses
);
2201 data
->accesses
= NULL
;
2206 df
->must_no_source
= isl_union_map_union(df
->must_no_source
,
2207 isl_union_map_from_map(isl_flow_get_no_source(flow
, 1)));
2208 df
->may_no_source
= isl_union_map_union(df
->may_no_source
,
2209 isl_union_map_from_map(isl_flow_get_no_source(flow
, 0)));
2211 for (i
= 0; i
< flow
->n_source
; ++i
) {
2213 dep
= isl_union_map_from_map(isl_map_copy(flow
->dep
[i
].map
));
2214 if (flow
->dep
[i
].must
)
2215 df
->must_dep
= isl_union_map_union(df
->must_dep
, dep
);
2217 df
->may_dep
= isl_union_map_union(df
->may_dep
, dep
);
2220 isl_flow_free(flow
);
2222 sched_info_free(data
->sink_info
);
2223 if (data
->source_info
) {
2224 for (i
= 0; i
< data
->count
; ++i
)
2225 sched_info_free(data
->source_info
[i
]);
2226 free(data
->source_info
);
2228 isl_space_free(data
->dim
);
2233 isl_access_info_free(data
->accesses
);
2234 sched_info_free(data
->sink_info
);
2235 if (data
->source_info
) {
2236 for (i
= 0; i
< data
->count
; ++i
)
2237 sched_info_free(data
->source_info
[i
]);
2238 free(data
->source_info
);
2240 isl_space_free(data
->dim
);
2243 return isl_stat_error
;
2246 /* Remove the must accesses from the may accesses.
2248 * A must access always trumps a may access, so there is no need
2249 * for a must access to also be considered as a may access. Doing so
2250 * would only cost extra computations only to find out that
2251 * the duplicated may access does not make any difference.
2253 static __isl_give isl_union_access_info
*isl_union_access_info_normalize(
2254 __isl_take isl_union_access_info
*access
)
2258 access
->access
[isl_access_may_source
] =
2259 isl_union_map_subtract(access
->access
[isl_access_may_source
],
2260 isl_union_map_copy(access
->access
[isl_access_must_source
]));
2261 if (!access
->access
[isl_access_may_source
])
2262 return isl_union_access_info_free(access
);
2267 /* Given a description of the "sink" accesses, the "source" accesses and
2268 * a schedule, compute for each instance of a sink access
2269 * and for each element accessed by that instance,
2270 * the possible or definite source accesses that last accessed the
2271 * element accessed by the sink access before this sink access
2272 * in the sense that there is no intermediate definite source access.
2274 * The must_no_source and may_no_source elements of the result
2275 * are subsets of access->sink. The elements must_dep and may_dep
2276 * map domain elements of access->{may,must)_source to
2277 * domain elements of access->sink.
2279 * This function is used when only the schedule map representation
2282 * We first prepend the schedule dimensions to the domain
2283 * of the accesses so that we can easily compare their relative order.
2284 * Then we consider each sink access individually in compute_flow.
2286 static __isl_give isl_union_flow
*compute_flow_union_map(
2287 __isl_take isl_union_access_info
*access
)
2289 struct isl_compute_flow_data data
;
2290 isl_union_map
*sink
;
2292 access
= isl_union_access_info_align_params(access
);
2293 access
= isl_union_access_info_introduce_schedule(access
);
2297 data
.must_source
= access
->access
[isl_access_must_source
];
2298 data
.may_source
= access
->access
[isl_access_may_source
];
2300 sink
= access
->access
[isl_access_sink
];
2301 data
.flow
= isl_union_flow_alloc(isl_union_map_get_space(sink
));
2303 if (isl_union_map_foreach_map(sink
, &compute_flow
, &data
) < 0)
2306 data
.flow
= isl_union_flow_drop_schedule(data
.flow
);
2308 isl_union_access_info_free(access
);
2311 isl_union_access_info_free(access
);
2312 isl_union_flow_free(data
.flow
);
2316 /* A schedule access relation.
2318 * The access relation "access" is of the form [S -> D] -> A,
2319 * where S corresponds to the prefix schedule at "node".
2320 * "must" is only relevant for source accesses and indicates
2321 * whether the access is a must source or a may source.
2323 struct isl_scheduled_access
{
2326 isl_schedule_node
*node
;
2329 /* Data structure for keeping track of individual scheduled sink and source
2330 * accesses when computing dependence analysis based on a schedule tree.
2332 * "n_sink" is the number of used entries in "sink"
2333 * "n_source" is the number of used entries in "source"
2335 * "set_sink", "must" and "node" are only used inside collect_sink_source,
2336 * to keep track of the current node and
2337 * of what extract_sink_source needs to do.
2339 struct isl_compute_flow_schedule_data
{
2340 isl_union_access_info
*access
;
2345 struct isl_scheduled_access
*sink
;
2346 struct isl_scheduled_access
*source
;
2350 isl_schedule_node
*node
;
2353 /* Align the parameters of all sinks with all sources.
2355 * If there are no sinks or no sources, then no alignment is needed.
2357 static void isl_compute_flow_schedule_data_align_params(
2358 struct isl_compute_flow_schedule_data
*data
)
2363 if (data
->n_sink
== 0 || data
->n_source
== 0)
2366 space
= isl_map_get_space(data
->sink
[0].access
);
2368 for (i
= 1; i
< data
->n_sink
; ++i
)
2369 space
= isl_space_align_params(space
,
2370 isl_map_get_space(data
->sink
[i
].access
));
2371 for (i
= 0; i
< data
->n_source
; ++i
)
2372 space
= isl_space_align_params(space
,
2373 isl_map_get_space(data
->source
[i
].access
));
2375 for (i
= 0; i
< data
->n_sink
; ++i
)
2376 data
->sink
[i
].access
=
2377 isl_map_align_params(data
->sink
[i
].access
,
2378 isl_space_copy(space
));
2379 for (i
= 0; i
< data
->n_source
; ++i
)
2380 data
->source
[i
].access
=
2381 isl_map_align_params(data
->source
[i
].access
,
2382 isl_space_copy(space
));
2384 isl_space_free(space
);
2387 /* Free all the memory referenced from "data".
2388 * Do not free "data" itself as it may be allocated on the stack.
2390 static void isl_compute_flow_schedule_data_clear(
2391 struct isl_compute_flow_schedule_data
*data
)
2398 for (i
= 0; i
< data
->n_sink
; ++i
) {
2399 isl_map_free(data
->sink
[i
].access
);
2400 isl_schedule_node_free(data
->sink
[i
].node
);
2403 for (i
= 0; i
< data
->n_source
; ++i
) {
2404 isl_map_free(data
->source
[i
].access
);
2405 isl_schedule_node_free(data
->source
[i
].node
);
2411 /* isl_schedule_foreach_schedule_node_top_down callback for counting
2412 * (an upper bound on) the number of sinks and sources.
2414 * Sinks and sources are only extracted at leaves of the tree,
2415 * so we skip the node if it is not a leaf.
2416 * Otherwise we increment data->n_sink and data->n_source with
2417 * the number of spaces in the sink and source access domains
2418 * that reach this node.
2420 static isl_bool
count_sink_source(__isl_keep isl_schedule_node
*node
,
2423 struct isl_compute_flow_schedule_data
*data
= user
;
2424 isl_union_set
*domain
;
2425 isl_union_map
*umap
;
2426 isl_bool r
= isl_bool_false
;
2428 if (isl_schedule_node_get_type(node
) != isl_schedule_node_leaf
)
2429 return isl_bool_true
;
2431 domain
= isl_schedule_node_get_universe_domain(node
);
2433 umap
= isl_union_map_copy(data
->access
->access
[isl_access_sink
]);
2434 umap
= isl_union_map_intersect_domain(umap
, isl_union_set_copy(domain
));
2435 data
->n_sink
+= isl_union_map_n_map(umap
);
2436 isl_union_map_free(umap
);
2440 umap
= isl_union_map_copy(data
->access
->access
[isl_access_must_source
]);
2441 umap
= isl_union_map_intersect_domain(umap
, isl_union_set_copy(domain
));
2442 data
->n_source
+= isl_union_map_n_map(umap
);
2443 isl_union_map_free(umap
);
2447 umap
= isl_union_map_copy(data
->access
->access
[isl_access_may_source
]);
2448 umap
= isl_union_map_intersect_domain(umap
, isl_union_set_copy(domain
));
2449 data
->n_source
+= isl_union_map_n_map(umap
);
2450 isl_union_map_free(umap
);
2454 isl_union_set_free(domain
);
2459 /* Add a single scheduled sink or source (depending on data->set_sink)
2460 * with scheduled access relation "map", must property data->must and
2461 * schedule node data->node to the list of sinks or sources.
2463 static isl_stat
extract_sink_source(__isl_take isl_map
*map
, void *user
)
2465 struct isl_compute_flow_schedule_data
*data
= user
;
2466 struct isl_scheduled_access
*access
;
2469 access
= data
->sink
+ data
->n_sink
++;
2471 access
= data
->source
+ data
->n_source
++;
2473 access
->access
= map
;
2474 access
->must
= data
->must
;
2475 access
->node
= isl_schedule_node_copy(data
->node
);
2480 /* isl_schedule_foreach_schedule_node_top_down callback for collecting
2481 * individual scheduled source and sink accesses (taking into account
2482 * the domain of the schedule).
2484 * We only collect accesses at the leaves of the schedule tree.
2485 * We prepend the schedule dimensions at the leaf to the iteration
2486 * domains of the source and sink accesses and then extract
2487 * the individual accesses (per space).
2489 * In particular, if the prefix schedule at the node is of the form
2493 * while the access relations are of the form
2497 * then the updated access relations are of the form
2501 * Note that S consists of a single space such that introducing S
2502 * in the access relations does not increase the number of spaces.
2504 static isl_bool
collect_sink_source(__isl_keep isl_schedule_node
*node
,
2507 struct isl_compute_flow_schedule_data
*data
= user
;
2508 isl_union_map
*prefix
;
2509 isl_union_map
*umap
;
2510 isl_bool r
= isl_bool_false
;
2512 if (isl_schedule_node_get_type(node
) != isl_schedule_node_leaf
)
2513 return isl_bool_true
;
2517 prefix
= isl_schedule_node_get_prefix_schedule_relation(node
);
2518 prefix
= isl_union_map_reverse(prefix
);
2519 prefix
= isl_union_map_range_map(prefix
);
2522 umap
= isl_union_map_copy(data
->access
->access
[isl_access_sink
]);
2523 umap
= isl_union_map_apply_range(isl_union_map_copy(prefix
), umap
);
2524 if (isl_union_map_foreach_map(umap
, &extract_sink_source
, data
) < 0)
2526 isl_union_map_free(umap
);
2530 umap
= isl_union_map_copy(data
->access
->access
[isl_access_must_source
]);
2531 umap
= isl_union_map_apply_range(isl_union_map_copy(prefix
), umap
);
2532 if (isl_union_map_foreach_map(umap
, &extract_sink_source
, data
) < 0)
2534 isl_union_map_free(umap
);
2538 umap
= isl_union_map_copy(data
->access
->access
[isl_access_may_source
]);
2539 umap
= isl_union_map_apply_range(isl_union_map_copy(prefix
), umap
);
2540 if (isl_union_map_foreach_map(umap
, &extract_sink_source
, data
) < 0)
2542 isl_union_map_free(umap
);
2544 isl_union_map_free(prefix
);
2549 /* isl_access_info_compute_flow callback for determining whether
2550 * the shared nesting level and the ordering within that level
2551 * for two scheduled accesses for use in compute_single_flow.
2553 * The tokens passed to this function refer to the leaves
2554 * in the schedule tree where the accesses take place.
2556 * If n is the shared number of loops, then we need to return
2557 * "2 * n + 1" if "first" precedes "second" inside the innermost
2558 * shared loop and "2 * n" otherwise.
2560 * The innermost shared ancestor may be the leaves themselves
2561 * if the accesses take place in the same leaf. Otherwise,
2562 * it is either a set node or a sequence node. Only in the case
2563 * of a sequence node do we consider one access to precede the other.
2565 static int before_node(void *first
, void *second
)
2567 isl_schedule_node
*node1
= first
;
2568 isl_schedule_node
*node2
= second
;
2569 isl_schedule_node
*shared
;
2573 shared
= isl_schedule_node_get_shared_ancestor(node1
, node2
);
2577 depth
= isl_schedule_node_get_schedule_depth(shared
);
2578 if (isl_schedule_node_get_type(shared
) == isl_schedule_node_sequence
) {
2581 pos1
= isl_schedule_node_get_ancestor_child_position(node1
,
2583 pos2
= isl_schedule_node_get_ancestor_child_position(node2
,
2585 before
= pos1
< pos2
;
2588 isl_schedule_node_free(shared
);
2590 return 2 * depth
+ before
;
2593 /* Add the scheduled sources from "data" that access
2594 * the same data space as "sink" to "access".
2596 static __isl_give isl_access_info
*add_matching_sources(
2597 __isl_take isl_access_info
*access
, struct isl_scheduled_access
*sink
,
2598 struct isl_compute_flow_schedule_data
*data
)
2603 space
= isl_space_range(isl_map_get_space(sink
->access
));
2604 for (i
= 0; i
< data
->n_source
; ++i
) {
2605 struct isl_scheduled_access
*source
;
2606 isl_space
*source_space
;
2609 source
= &data
->source
[i
];
2610 source_space
= isl_map_get_space(source
->access
);
2611 source_space
= isl_space_range(source_space
);
2612 eq
= isl_space_is_equal(space
, source_space
);
2613 isl_space_free(source_space
);
2620 access
= isl_access_info_add_source(access
,
2621 isl_map_copy(source
->access
), source
->must
, source
->node
);
2624 isl_space_free(space
);
2627 isl_space_free(space
);
2628 isl_access_info_free(access
);
2632 /* Given a scheduled sink access relation "sink", compute the corresponding
2633 * dependences on the sources in "data" and add the computed dependences
2636 * The dependences computed by access_info_compute_flow_core are of the form
2638 * [S -> I] -> [[S' -> I'] -> A]
2640 * The schedule dimensions are projected out by first currying the range,
2643 * [S -> I] -> [S' -> [I' -> A]]
2645 * and then computing the factor range
2649 static __isl_give isl_union_flow
*compute_single_flow(
2650 __isl_take isl_union_flow
*uf
, struct isl_scheduled_access
*sink
,
2651 struct isl_compute_flow_schedule_data
*data
)
2654 isl_access_info
*access
;
2661 access
= isl_access_info_alloc(isl_map_copy(sink
->access
), sink
->node
,
2662 &before_node
, data
->n_source
);
2663 access
= add_matching_sources(access
, sink
, data
);
2665 flow
= access_info_compute_flow_core(access
);
2667 return isl_union_flow_free(uf
);
2669 map
= isl_map_domain_factor_range(isl_flow_get_no_source(flow
, 1));
2670 uf
->must_no_source
= isl_union_map_union(uf
->must_no_source
,
2671 isl_union_map_from_map(map
));
2672 map
= isl_map_domain_factor_range(isl_flow_get_no_source(flow
, 0));
2673 uf
->may_no_source
= isl_union_map_union(uf
->may_no_source
,
2674 isl_union_map_from_map(map
));
2676 for (i
= 0; i
< flow
->n_source
; ++i
) {
2679 map
= isl_map_range_curry(isl_map_copy(flow
->dep
[i
].map
));
2680 map
= isl_map_factor_range(map
);
2681 dep
= isl_union_map_from_map(map
);
2682 if (flow
->dep
[i
].must
)
2683 uf
->must_dep
= isl_union_map_union(uf
->must_dep
, dep
);
2685 uf
->may_dep
= isl_union_map_union(uf
->may_dep
, dep
);
2688 isl_flow_free(flow
);
2693 /* Given a description of the "sink" accesses, the "source" accesses and
2694 * a schedule, compute for each instance of a sink access
2695 * and for each element accessed by that instance,
2696 * the possible or definite source accesses that last accessed the
2697 * element accessed by the sink access before this sink access
2698 * in the sense that there is no intermediate definite source access.
2699 * Only consider dependences between statement instances that belong
2700 * to the domain of the schedule.
2702 * The must_no_source and may_no_source elements of the result
2703 * are subsets of access->sink. The elements must_dep and may_dep
2704 * map domain elements of access->{may,must)_source to
2705 * domain elements of access->sink.
2707 * This function is used when a schedule tree representation
2710 * We extract the individual scheduled source and sink access relations
2711 * (taking into account the domain of the schedule) and
2712 * then compute dependences for each scheduled sink individually.
2714 static __isl_give isl_union_flow
*compute_flow_schedule(
2715 __isl_take isl_union_access_info
*access
)
2717 struct isl_compute_flow_schedule_data data
= { access
};
2721 isl_union_flow
*flow
;
2723 ctx
= isl_union_access_info_get_ctx(access
);
2727 if (isl_schedule_foreach_schedule_node_top_down(access
->schedule
,
2728 &count_sink_source
, &data
) < 0)
2731 n
= data
.n_sink
+ data
.n_source
;
2732 data
.sink
= isl_calloc_array(ctx
, struct isl_scheduled_access
, n
);
2733 if (n
&& !data
.sink
)
2735 data
.source
= data
.sink
+ data
.n_sink
;
2739 if (isl_schedule_foreach_schedule_node_top_down(access
->schedule
,
2740 &collect_sink_source
, &data
) < 0)
2743 space
= isl_union_map_get_space(access
->access
[isl_access_sink
]);
2744 flow
= isl_union_flow_alloc(space
);
2746 isl_compute_flow_schedule_data_align_params(&data
);
2748 for (i
= 0; i
< data
.n_sink
; ++i
)
2749 flow
= compute_single_flow(flow
, &data
.sink
[i
], &data
);
2751 isl_compute_flow_schedule_data_clear(&data
);
2753 isl_union_access_info_free(access
);
2756 isl_union_access_info_free(access
);
2757 isl_compute_flow_schedule_data_clear(&data
);
2761 /* Given a description of the "sink" accesses, the "source" accesses and
2762 * a schedule, compute for each instance of a sink access
2763 * and for each element accessed by that instance,
2764 * the possible or definite source accesses that last accessed the
2765 * element accessed by the sink access before this sink access
2766 * in the sense that there is no intermediate definite source access.
2768 * The must_no_source and may_no_source elements of the result
2769 * are subsets of access->sink. The elements must_dep and may_dep
2770 * map domain elements of access->{may,must)_source to
2771 * domain elements of access->sink.
2773 * We check whether the schedule is available as a schedule tree
2774 * or a schedule map and call the corresponding function to perform
2777 __isl_give isl_union_flow
*isl_union_access_info_compute_flow(
2778 __isl_take isl_union_access_info
*access
)
2780 access
= isl_union_access_info_normalize(access
);
2783 if (access
->schedule
)
2784 return compute_flow_schedule(access
);
2786 return compute_flow_union_map(access
);
2789 /* Print the information contained in "flow" to "p".
2790 * The information is printed as a YAML document.
2792 __isl_give isl_printer
*isl_printer_print_union_flow(
2793 __isl_take isl_printer
*p
, __isl_keep isl_union_flow
*flow
)
2795 isl_union_map
*umap
;
2798 return isl_printer_free(p
);
2800 p
= isl_printer_yaml_start_mapping(p
);
2801 umap
= isl_union_flow_get_full_must_dependence(flow
);
2802 p
= print_union_map_field(p
, "must_dependence", umap
);
2803 isl_union_map_free(umap
);
2804 umap
= isl_union_flow_get_full_may_dependence(flow
);
2805 p
= print_union_map_field(p
, "may_dependence", umap
);
2806 isl_union_map_free(umap
);
2807 p
= print_union_map_field(p
, "must_no_source", flow
->must_no_source
);
2808 umap
= isl_union_flow_get_may_no_source(flow
);
2809 p
= print_union_map_field(p
, "may_no_source", umap
);
2810 isl_union_map_free(umap
);
2811 p
= isl_printer_yaml_end_mapping(p
);
2816 /* Return a string representation of the information in "flow".
2817 * The information is printed in flow format.
2819 __isl_give
char *isl_union_flow_to_str(__isl_keep isl_union_flow
*flow
)
2827 p
= isl_printer_to_str(isl_union_flow_get_ctx(flow
));
2828 p
= isl_printer_set_yaml_style(p
, ISL_YAML_STYLE_FLOW
);
2829 p
= isl_printer_print_union_flow(p
, flow
);
2830 s
= isl_printer_get_str(p
);
2831 isl_printer_free(p
);
2836 /* Given a collection of "sink" and "source" accesses,
2837 * compute for each iteration of a sink access
2838 * and for each element accessed by that iteration,
2839 * the source access in the list that last accessed the
2840 * element accessed by the sink access before this sink access.
2841 * Each access is given as a map from the loop iterators
2842 * to the array indices.
2843 * The result is a relations between source and sink
2844 * iterations and a subset of the domain of the sink accesses,
2845 * corresponding to those iterations that access an element
2846 * not previously accessed.
2848 * We collect the inputs in an isl_union_access_info object,
2849 * call isl_union_access_info_compute_flow and extract
2850 * the outputs from the result.
2852 int isl_union_map_compute_flow(__isl_take isl_union_map
*sink
,
2853 __isl_take isl_union_map
*must_source
,
2854 __isl_take isl_union_map
*may_source
,
2855 __isl_take isl_union_map
*schedule
,
2856 __isl_give isl_union_map
**must_dep
, __isl_give isl_union_map
**may_dep
,
2857 __isl_give isl_union_map
**must_no_source
,
2858 __isl_give isl_union_map
**may_no_source
)
2860 isl_union_access_info
*access
;
2861 isl_union_flow
*flow
;
2863 access
= isl_union_access_info_from_sink(sink
);
2864 access
= isl_union_access_info_set_must_source(access
, must_source
);
2865 access
= isl_union_access_info_set_may_source(access
, may_source
);
2866 access
= isl_union_access_info_set_schedule_map(access
, schedule
);
2867 flow
= isl_union_access_info_compute_flow(access
);
2870 *must_dep
= isl_union_flow_get_must_dependence(flow
);
2872 *may_dep
= isl_union_flow_get_non_must_dependence(flow
);
2874 *must_no_source
= isl_union_flow_get_must_no_source(flow
);
2876 *may_no_source
= isl_union_flow_get_non_must_no_source(flow
);
2878 isl_union_flow_free(flow
);
2880 if ((must_dep
&& !*must_dep
) || (may_dep
&& !*may_dep
) ||
2881 (must_no_source
&& !*must_no_source
) ||
2882 (may_no_source
&& !*may_no_source
))
2888 *must_dep
= isl_union_map_free(*must_dep
);
2890 *may_dep
= isl_union_map_free(*may_dep
);
2892 *must_no_source
= isl_union_map_free(*must_no_source
);
2894 *may_no_source
= isl_union_map_free(*may_no_source
);