+2012-01-27 Andrey Belevantsev <abel@ispras.ru>
+
+ PR middle-end/51389
+ * Makefile.in (tree-data-ref.o): Depend on $(PARAMS_H).
+ * tree-data-ref.h (find_data_references_in_loop): Remove declaration.
+ * tree-data-ref.c (find_data_references_in_loop): Make static.
+ (compute_all_dependences): Change return type to bool. Bail out
+ for too many datarefs in a loop. Move the hunk resetting the data
+ dependences vector from ...
+ (compute_data_dependences_for_loop): ... here. Account for
+ compute_all_dependences returning false.
+ (compute_data_dependences_for_bb): Likewise.
+ * params.def (PARAM_LOOP_MAX_DATAREFS_FOR_DATADEPS): New param.
+ * doc/invoke.texi (loop-max-datarefs-for-datadeps): Document it.
+
2012-01-27 Richard Guenther <rguenther@suse.de>
PR middle-end/51959
$(TREE_PASS_H) $(PARAMS_H) gt-tree-scalar-evolution.h
tree-data-ref.o : tree-data-ref.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \
gimple-pretty-print.h $(TREE_FLOW_H) $(CFGLOOP_H) $(TREE_DATA_REF_H) \
- $(TREE_PASS_H) langhooks.h tree-affine.h
+ $(TREE_PASS_H) langhooks.h tree-affine.h $(PARAMS_H)
sese.o : sese.c sese.h $(CONFIG_H) $(SYSTEM_H) coretypes.h tree-pretty-print.h \
$(TREE_FLOW_H) $(CFGLOOP_H) $(TREE_DATA_REF_H) tree-pass.h value-prof.h
graphite.o : graphite.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(DIAGNOSTIC_CORE_H) \
motion optimization performed on them. The default value of the
parameter is 1000 for -O1 and 10000 for -O2 and above.
+@item loop-max-datarefs-for-datadeps
+Building data dapendencies is expensive for very large loops. This
+parameter limits the number of data references in loops that are
+considered for data dependence analysis. These large loops will not
+be handled then by the optimizations using loop data dependencies.
+The default value is 1000.
+
@item max-vartrack-size
Sets a maximum number of hash table slots to use during variable
tracking dataflow analysis of any function. If this limit is exceeded
"maximum number of basic blocks per function to be analyzed by Graphite",
100, 0, 0)
+/* Avoid data dependence analysis on very large loops. */
+DEFPARAM (PARAM_LOOP_MAX_DATAREFS_FOR_DATADEPS,
+ "loop-max-datarefs-for-datadeps",
+ "Maximum number of datarefs in loop for building loop data dependencies",
+ 1000, 0, 0)
+
/* Avoid doing loop invariant motion on very large loops. */
DEFPARAM (PARAM_LOOP_INVARIANT_MAX_BBS_IN_LOOP,
#include "tree-pass.h"
#include "langhooks.h"
#include "tree-affine.h"
+#include "params.h"
static struct datadep_stats
{
/* Compute in DEPENDENCE_RELATIONS the data dependence graph for all
the data references in DATAREFS, in the LOOP_NEST. When
COMPUTE_SELF_AND_RR is FALSE, don't compute read-read and self
- relations. */
+ relations. Return true when successful, i.e. data references number
+ is small enough to be handled. */
-void
+bool
compute_all_dependences (VEC (data_reference_p, heap) *datarefs,
VEC (ddr_p, heap) **dependence_relations,
VEC (loop_p, heap) *loop_nest,
struct data_reference *a, *b;
unsigned int i, j;
+ if ((int) VEC_length (data_reference_p, datarefs)
+ > PARAM_VALUE (PARAM_LOOP_MAX_DATAREFS_FOR_DATADEPS))
+ {
+ struct data_dependence_relation *ddr;
+
+ /* Insert a single relation into dependence_relations:
+ chrec_dont_know. */
+ ddr = initialize_data_dependence_relation (NULL, NULL, loop_nest);
+ VEC_safe_push (ddr_p, heap, *dependence_relations, ddr);
+ return false;
+ }
+
FOR_EACH_VEC_ELT (data_reference_p, datarefs, i, a)
for (j = i + 1; VEC_iterate (data_reference_p, datarefs, j, b); j++)
if (DR_IS_WRITE (a) || DR_IS_WRITE (b) || compute_self_and_rr)
if (loop_nest)
compute_affine_dependence (ddr, VEC_index (loop_p, loop_nest, 0));
}
+
+ return true;
}
/* Stores the locations of memory references in STMT to REFERENCES. Returns
TODO: This function should be made smarter so that it can handle address
arithmetic as if they were array accesses, etc. */
-tree
+static tree
find_data_references_in_loop (struct loop *loop,
VEC (data_reference_p, heap) **datarefs)
{
dependences. */
if (!loop
|| !find_loop_nest (loop, loop_nest)
- || find_data_references_in_loop (loop, datarefs) == chrec_dont_know)
- {
- struct data_dependence_relation *ddr;
-
- /* Insert a single relation into dependence_relations:
- chrec_dont_know. */
- ddr = initialize_data_dependence_relation (NULL, NULL, *loop_nest);
- VEC_safe_push (ddr_p, heap, *dependence_relations, ddr);
- res = false;
- }
- else
- compute_all_dependences (*datarefs, dependence_relations, *loop_nest,
- compute_self_and_read_read_dependences);
+ || find_data_references_in_loop (loop, datarefs) == chrec_dont_know
+ || !compute_all_dependences (*datarefs, dependence_relations, *loop_nest,
+ compute_self_and_read_read_dependences))
+ res = false;
if (dump_file && (dump_flags & TDF_STATS))
{
if (find_data_references_in_bb (NULL, bb, datarefs) == chrec_dont_know)
return false;
- compute_all_dependences (*datarefs, dependence_relations, NULL,
- compute_self_and_read_read_dependences);
- return true;
+ return compute_all_dependences (*datarefs, dependence_relations, NULL,
+ compute_self_and_read_read_dependences);
}
/* Entry point (for testing only). Analyze all the data references
extern bool compute_data_dependences_for_bb (basic_block, bool,
VEC (data_reference_p, heap) **,
VEC (ddr_p, heap) **);
-extern tree find_data_references_in_loop (struct loop *,
- VEC (data_reference_p, heap) **);
extern void print_direction_vector (FILE *, lambda_vector, int);
extern void print_dir_vectors (FILE *, VEC (lambda_vector, heap) *, int);
extern void print_dist_vectors (FILE *, VEC (lambda_vector, heap) *, int);
extern struct data_dependence_relation *initialize_data_dependence_relation
(struct data_reference *, struct data_reference *, VEC (loop_p, heap) *);
extern void compute_self_dependence (struct data_dependence_relation *);
-extern void compute_all_dependences (VEC (data_reference_p, heap) *,
+extern bool compute_all_dependences (VEC (data_reference_p, heap) *,
VEC (ddr_p, heap) **, VEC (loop_p, heap) *,
bool);
extern tree find_data_references_in_bb (struct loop *, basic_block,
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