/* A scheduling optimizer for Graphite
- Copyright (C) 2012-2015 Free Software Foundation, Inc.
+ Copyright (C) 2012-2020 Free Software Foundation, Inc.
Contributed by Tobias Grosser <tobias@grosser.es>.
This file is part of GCC.
#include "tree-ssa-loop.h"
#include "cfgloop.h"
#include "tree-data-ref.h"
-#include "params.h"
#include "dumpfile.h"
-
-#include <isl/constraint.h>
-#include <isl/set.h>
-#include <isl/union_set.h>
-#include <isl/map.h>
-#include <isl/union_map.h>
-#include <isl/schedule.h>
-#include <isl/band.h>
-#include <isl/aff.h>
-#include <isl/options.h>
-#include <isl/ctx.h>
-#ifdef HAVE_ISL_OPTIONS_SET_SCHEDULE_SERIALIZE_SCCS
-#include <isl/schedule_node.h>
-#include <isl/ast_build.h>
-#endif
-
+#include "tree-vectorizer.h"
#include "graphite.h"
-#ifdef HAVE_ISL_OPTIONS_SET_SCHEDULE_SERIALIZE_SCCS
/* get_schedule_for_node_st - Improve schedule for the schedule node.
Only Simple loop tiling is considered. */
if (type != isl_schedule_node_leaf)
return node;
- if (dims <= 1 || !isl_schedule_node_band_get_permutable (node))
+ long tile_size = param_loop_block_tile_size;
+ if (dims <= 1
+ || tile_size == 0
+ || !isl_schedule_node_band_get_permutable (node))
{
if (dump_file && dump_flags)
fprintf (dump_file, "not tiled\n");
/* Tile loops. */
space = isl_schedule_node_band_get_space (node);
isl_multi_val *sizes = isl_multi_val_zero (space);
- long tile_size = PARAM_VALUE (PARAM_LOOP_BLOCK_TILE_SIZE);
isl_ctx *ctx = isl_schedule_node_get_ctx (node);
for (unsigned i = 0; i < dims; i++)
return node;
}
-/* get_schedule_map_st - Improve the schedule by performing other loop
- optimizations. _st ending is for schedule tree version of this
- function (see get_schedule_map below for the band forest version).
-
- Do a depth-first post-order traversal of the nodes in a schedule
- tree and apply get_schedule_for_node_st on them to improve the schedule.
- */
-
-static __isl_give isl_union_map *
-get_schedule_map_st (__isl_keep isl_schedule *schedule)
-{
-
- schedule = isl_schedule_map_schedule_node_bottom_up (schedule,
- get_schedule_for_node_st,
- NULL);
- isl_union_map *schedule_map = isl_schedule_get_map (schedule);
- return schedule_map;
-}
-#else
-
-/* get_tile_map - Create a map that describes a n-dimensonal tiling.
-
- get_tile_map creates a map from a n-dimensional scattering space into an
- 2*n-dimensional scattering space. The map describes a rectangular tiling.
-
- Example:
- SCHEDULE_DIMENSIONS = 2, PARAMETER_DIMENSIONS = 1, TILE_SIZE = 32
-
- tile_map := [p0] -> {[s0, s1] -> [t0, t1, s0, s1]:
- t0 % 32 = 0 and t0 <= s0 < t0 + 32 and
- t1 % 32 = 0 and t1 <= s1 < t1 + 32}
-
- Before tiling:
-
- for (i = 0; i < N; i++)
- for (j = 0; j < M; j++)
- S(i,j)
-
- After tiling:
-
- for (t_i = 0; t_i < N; i+=32)
- for (t_j = 0; t_j < M; j+=32)
- for (i = t_i; i < min(t_i + 32, N); i++) | Unknown that N % 32 = 0
- for (j = t_j; j < t_j + 32; j++) | Known that M % 32 = 0
- S(i,j)
- */
-
-static isl_basic_map *
-get_tile_map (isl_ctx *ctx, int schedule_dimensions, int tile_size)
-{
- /* We construct
-
- tile_map := [p0] -> {[s0, s1] -> [t0, t1, p0, p1, a0, a1]:
- s0 = a0 * 32 and s0 = p0 and t0 <= p0 < t0 + 32 and
- s1 = a1 * 32 and s1 = p1 and t1 <= p1 < t1 + 32}
-
- and project out the auxilary dimensions a0 and a1. */
- isl_space *space
- = isl_space_alloc (ctx, 0, schedule_dimensions, schedule_dimensions * 3);
- isl_basic_map *tile_map = isl_basic_map_universe (isl_space_copy (space));
-
- isl_local_space *local_space = isl_local_space_from_space (space);
-
- for (int x = 0; x < schedule_dimensions; x++)
- {
- int sX = x;
- int tX = x;
- int pX = schedule_dimensions + x;
- int aX = 2 * schedule_dimensions + x;
-
- isl_constraint *c;
-
- /* sX = aX * tile_size; */
- c = isl_equality_alloc (isl_local_space_copy (local_space));
- isl_constraint_set_coefficient_si (c, isl_dim_out, sX, 1);
- isl_constraint_set_coefficient_si (c, isl_dim_out, aX, -tile_size);
- tile_map = isl_basic_map_add_constraint (tile_map, c);
-
- /* pX = sX; */
- c = isl_equality_alloc (isl_local_space_copy (local_space));
- isl_constraint_set_coefficient_si (c, isl_dim_out, pX, 1);
- isl_constraint_set_coefficient_si (c, isl_dim_in, sX, -1);
- tile_map = isl_basic_map_add_constraint (tile_map, c);
-
- /* tX <= pX */
- c = isl_inequality_alloc (isl_local_space_copy (local_space));
- isl_constraint_set_coefficient_si (c, isl_dim_out, pX, 1);
- isl_constraint_set_coefficient_si (c, isl_dim_out, tX, -1);
- tile_map = isl_basic_map_add_constraint (tile_map, c);
-
- /* pX <= tX + (tile_size - 1) */
- c = isl_inequality_alloc (isl_local_space_copy (local_space));
- isl_constraint_set_coefficient_si (c, isl_dim_out, tX, 1);
- isl_constraint_set_coefficient_si (c, isl_dim_out, pX, -1);
- isl_constraint_set_constant_si (c, tile_size - 1);
- tile_map = isl_basic_map_add_constraint (tile_map, c);
- }
-
- /* Project out auxiliary dimensions.
-
- The auxiliary dimensions are transformed into existentially quantified
- ones.
- This reduces the number of visible scattering dimensions and allows isl
- to produces better code. */
- tile_map =
- isl_basic_map_project_out (tile_map, isl_dim_out,
- 2 * schedule_dimensions, schedule_dimensions);
- isl_local_space_free (local_space);
- return tile_map;
-}
-
-/* get_schedule_for_band - Get the schedule for this BAND.
-
- Polly applies transformations like tiling on top of the isl calculated
- value.
- This can influence the number of scheduling dimension. The number of
- schedule dimensions is returned in DIMENSIONS. */
-
-static isl_union_map *
-get_schedule_for_band (isl_band *band, int *dimensions)
-{
- isl_union_map *partial_schedule;
- isl_ctx *ctx;
- isl_space *space;
- isl_basic_map *tile_map;
- isl_union_map *tile_umap;
-
- partial_schedule = isl_band_get_partial_schedule (band);
- *dimensions = isl_band_n_member (band);
-
- /* It does not make any sense to tile a band with just one dimension. */
- if (*dimensions == 1)
- {
- if (dump_file && dump_flags)
- fprintf (dump_file, "not tiled\n");
- return partial_schedule;
- }
-
- if (dump_file && dump_flags)
- fprintf (dump_file, "tiled by %d\n",
- PARAM_VALUE (PARAM_LOOP_BLOCK_TILE_SIZE));
-
- ctx = isl_union_map_get_ctx (partial_schedule);
- space = isl_union_map_get_space (partial_schedule);
-
- tile_map = get_tile_map (ctx, *dimensions,
- PARAM_VALUE (PARAM_LOOP_BLOCK_TILE_SIZE));
- tile_umap = isl_union_map_from_map (isl_map_from_basic_map (tile_map));
- tile_umap = isl_union_map_align_params (tile_umap, space);
- *dimensions = 2 * *dimensions;
-
- return isl_union_map_apply_range (partial_schedule, tile_umap);
-}
-
-
-/* get_schedule_for_band_list - Get the scheduling map for a list of bands.
-
- We walk recursively the forest of bands to combine the schedules of the
- individual bands to the overall schedule. In case tiling is requested,
- the individual bands are tiled. */
-
-static isl_union_map *
-get_schedule_for_band_list (isl_band_list *band_list)
-{
- int num_bands, i;
- isl_union_map *schedule;
- isl_ctx *ctx;
-
- ctx = isl_band_list_get_ctx (band_list);
- num_bands = isl_band_list_n_band (band_list);
- schedule = isl_union_map_empty (isl_space_params_alloc (ctx, 0));
-
- for (i = 0; i < num_bands; i++)
- {
- isl_band *band;
- isl_union_map *partial_schedule;
- int schedule_dimensions;
- isl_space *space;
-
- band = isl_band_list_get_band (band_list, i);
- partial_schedule = get_schedule_for_band (band, &schedule_dimensions);
- space = isl_union_map_get_space (partial_schedule);
-
- if (isl_band_has_children (band))
- {
- isl_band_list *children = isl_band_get_children (band);
- isl_union_map *suffixSchedule
- = get_schedule_for_band_list (children);
- partial_schedule
- = isl_union_map_flat_range_product (partial_schedule,
- suffixSchedule);
- isl_band_list_free (children);
- }
-
- schedule = isl_union_map_union (schedule, partial_schedule);
-
- isl_band_free (band);
- isl_space_free (space);
- }
-
- return schedule;
-}
-
-static isl_union_map *
-get_schedule_map (isl_schedule *schedule)
-{
- isl_band_list *bandList = isl_schedule_get_band_forest (schedule);
- isl_union_map *schedule_map = get_schedule_for_band_list (bandList);
- isl_band_list_free (bandList);
- return schedule_map;
-}
-#endif
-
-static isl_stat
-get_single_map (__isl_take isl_map *map, void *user)
-{
- isl_map **single_map = (isl_map **)user;
- *single_map = map;
- return isl_stat_ok;
-}
-
-static void
-apply_schedule_map_to_scop (scop_p scop, isl_union_map *schedule_map)
-{
- int i;
- poly_bb_p pbb;
-
- FOR_EACH_VEC_ELT (scop->pbbs, i, pbb)
- {
- isl_set *domain = isl_set_copy (pbb->domain);
- isl_map *stmt_schedule;
-
- isl_union_map *stmt_band
- = isl_union_map_intersect_domain (isl_union_map_copy (schedule_map),
- isl_union_set_from_set (domain));
- isl_union_map_foreach_map (stmt_band, get_single_map, &stmt_schedule);
- isl_map_free (pbb->transformed);
- pbb->transformed = stmt_schedule;
- isl_union_map_free (stmt_band);
- }
-}
-
static isl_union_set *
-scop_get_domains (scop_p scop ATTRIBUTE_UNUSED)
+scop_get_domains (scop_p scop)
{
int i;
poly_bb_p pbb;
FOR_EACH_VEC_ELT (scop->pbbs, i, pbb)
res = isl_union_set_add_set (res, isl_set_copy (pbb->domain));
- return res;
+ return res;
}
-static const int CONSTANT_BOUND = 20;
-
/* Compute the schedule for SCOP based on its parameters, domain and set of
constraints. Then apply the schedule to SCOP. */
-bool
+static bool
optimize_isl (scop_p scop)
{
-#ifdef HAVE_ISL_CTX_MAX_OPERATIONS
+ int old_err = isl_options_get_on_error (scop->isl_context);
int old_max_operations = isl_ctx_get_max_operations (scop->isl_context);
- int max_operations = PARAM_VALUE (PARAM_MAX_ISL_OPERATIONS);
+ int max_operations = param_max_isl_operations;
if (max_operations)
isl_ctx_set_max_operations (scop->isl_context, max_operations);
-#endif
isl_options_set_on_error (scop->isl_context, ISL_ON_ERROR_CONTINUE);
isl_union_set *domain = scop_get_domains (scop);
- isl_union_map *dependences = scop_get_dependences (scop);
- dependences
- = isl_union_map_gist_domain (dependences, isl_union_set_copy (domain));
- dependences
+
+ /* Simplify the dependences on the domain. */
+ scop_get_dependences (scop);
+ isl_union_map *dependences
+ = isl_union_map_gist_domain (isl_union_map_copy (scop->dependence),
+ isl_union_set_copy (domain));
+ isl_union_map *validity
= isl_union_map_gist_range (dependences, isl_union_set_copy (domain));
- isl_union_map *validity = dependences;
+
+ /* FIXME: proximity should not be validity. */
isl_union_map *proximity = isl_union_map_copy (validity);
-#ifdef HAVE_ISL_SCHED_CONSTRAINTS_COMPUTE_SCHEDULE
- isl_schedule_constraints *schedule_constraints;
- schedule_constraints = isl_schedule_constraints_on_domain (domain);
- schedule_constraints
- = isl_schedule_constraints_set_proximity (schedule_constraints,
- proximity);
- schedule_constraints
- = isl_schedule_constraints_set_validity (schedule_constraints,
- isl_union_map_copy (validity));
- schedule_constraints
- = isl_schedule_constraints_set_coincidence (schedule_constraints,
- validity);
-#endif
-
- isl_options_set_schedule_max_constant_term (scop->isl_context, CONSTANT_BOUND);
- isl_options_set_schedule_maximize_band_depth (scop->isl_context, 1);
-#ifdef HAVE_ISL_OPTIONS_SET_SCHEDULE_SERIALIZE_SCCS
- /* ISL-0.15 or later. */
+ isl_schedule_constraints *sc = isl_schedule_constraints_on_domain (domain);
+ sc = isl_schedule_constraints_set_proximity (sc, proximity);
+ sc = isl_schedule_constraints_set_validity (sc, isl_union_map_copy (validity));
+ sc = isl_schedule_constraints_set_coincidence (sc, validity);
+
isl_options_set_schedule_serialize_sccs (scop->isl_context, 0);
isl_options_set_schedule_maximize_band_depth (scop->isl_context, 1);
isl_options_set_schedule_max_constant_term (scop->isl_context, 20);
isl_options_set_schedule_max_coefficient (scop->isl_context, 20);
isl_options_set_tile_scale_tile_loops (scop->isl_context, 0);
- isl_options_set_coalesce_bounded_wrapping (scop->isl_context, 1);
- isl_options_set_ast_build_exploit_nested_bounds (scop->isl_context, 1);
+ /* Generate loop upper bounds that consist of the current loop iterator, an
+ operator (< or <=) and an expression not involving the iterator. If this
+ option is not set, then the current loop iterator may appear several times
+ in the upper bound. See the isl manual for more details. */
isl_options_set_ast_build_atomic_upper_bound (scop->isl_context, 1);
-#else
- isl_options_set_schedule_fuse (scop->isl_context, ISL_SCHEDULE_FUSE_MIN);
-#endif
-
-#ifdef HAVE_ISL_SCHED_CONSTRAINTS_COMPUTE_SCHEDULE
- isl_schedule *schedule
- = isl_schedule_constraints_compute_schedule (schedule_constraints);
-#else
- isl_schedule *schedule
- = isl_union_set_compute_schedule (domain, validity, proximity);
-#endif
- isl_options_set_on_error (scop->isl_context, ISL_ON_ERROR_ABORT);
+ scop->transformed_schedule = isl_schedule_constraints_compute_schedule (sc);
+ scop->transformed_schedule =
+ isl_schedule_map_schedule_node_bottom_up (scop->transformed_schedule,
+ get_schedule_for_node_st, NULL);
-#ifdef HAVE_ISL_CTX_MAX_OPERATIONS
+ isl_options_set_on_error (scop->isl_context, old_err);
isl_ctx_reset_operations (scop->isl_context);
isl_ctx_set_max_operations (scop->isl_context, old_max_operations);
- if (!schedule || isl_ctx_last_error (scop->isl_context) == isl_error_quota)
+ if (!scop->transformed_schedule
+ || isl_ctx_last_error (scop->isl_context) != isl_error_none)
{
- if (dump_file && dump_flags)
- fprintf (dump_file, "ISL timed out --param max-isl-operations=%d\n",
- max_operations);
- if (schedule)
- isl_schedule_free (schedule);
+ if (dump_enabled_p ())
+ {
+ dump_user_location_t loc = find_loop_location
+ (scop->scop_info->region.entry->dest->loop_father);
+ if (isl_ctx_last_error (scop->isl_context) == isl_error_quota)
+ dump_printf_loc (MSG_MISSED_OPTIMIZATION, loc,
+ "loop nest not optimized, optimization timed out "
+ "after %d operations [--param max-isl-operations]\n",
+ max_operations);
+ else
+ dump_printf_loc (MSG_MISSED_OPTIMIZATION, loc,
+ "loop nest not optimized, ISL signalled an error\n");
+ }
return false;
}
-#else
- if (!schedule)
- return false;
-#endif
-#ifdef HAVE_ISL_OPTIONS_SET_SCHEDULE_SERIALIZE_SCCS
- isl_union_map *schedule_map = get_schedule_map_st (schedule);
-#else
- isl_union_map *schedule_map = get_schedule_map (schedule);
-#endif
- apply_schedule_map_to_scop (scop, schedule_map);
+ gcc_assert (scop->original_schedule);
+ isl_union_map *original = isl_schedule_get_map (scop->original_schedule);
+ isl_union_map *transformed = isl_schedule_get_map (scop->transformed_schedule);
+ bool same_schedule = isl_union_map_is_equal (original, transformed);
+ isl_union_map_free (original);
+ isl_union_map_free (transformed);
+
+ if (same_schedule)
+ {
+ if (dump_enabled_p ())
+ {
+ dump_user_location_t loc = find_loop_location
+ (scop->scop_info->region.entry->dest->loop_father);
+ dump_printf_loc (MSG_NOTE, loc,
+ "loop nest not optimized, optimized schedule is "
+ "identical to original schedule\n");
+ }
+ if (dump_file)
+ print_schedule_ast (dump_file, scop->original_schedule, scop);
+ isl_schedule_free (scop->transformed_schedule);
+ scop->transformed_schedule = isl_schedule_copy (scop->original_schedule);
+ return flag_graphite_identity || flag_loop_parallelize_all;
+ }
+
+ return true;
+}
+
+/* Apply graphite transformations to all the basic blocks of SCOP. */
+
+bool
+apply_poly_transforms (scop_p scop)
+{
+ if (flag_loop_nest_optimize)
+ return optimize_isl (scop);
+
+ if (!flag_graphite_identity && !flag_loop_parallelize_all)
+ return false;
- isl_schedule_free (schedule);
- isl_union_map_free (schedule_map);
+ /* Generate code even if we did not apply any real transformation.
+ This also allows to check the performance for the identity
+ transformation: GIMPLE -> GRAPHITE -> GIMPLE. */
+ gcc_assert (scop->original_schedule);
+ scop->transformed_schedule = isl_schedule_copy (scop->original_schedule);
return true;
}