--- /dev/null
+/*
+ * Copyright 2011 INRIA Saclay
+ *
+ * Use of this software is governed by the GNU LGPLv2.1 license
+ *
+ * Written by Sven Verdoolaege, INRIA Saclay - Ile-de-France,
+ * Parc Club Orsay Universite, ZAC des vignes, 4 rue Jacques Monod,
+ * 91893 Orsay, France
+ */
+
+#include <isl_ctx_private.h>
+#include <isl_map_private.h>
+#include <isl_dim_private.h>
+#include <isl/hash.h>
+#include <isl/constraint.h>
+#include <isl/schedule.h>
+#include <isl_mat_private.h>
+#include <isl/set.h>
+#include <isl/seq.h>
+#include <isl_tab.h>
+#include <isl_dim_map.h>
+#include <isl_hmap_map_basic_set.h>
+#include <isl_qsort.h>
+
+/*
+ * The scheduling algorithm implemented in this file was inspired by
+ * Bondhugula et al., "Automatic Transformations for Communication-Minimized
+ * Parallelization and Locality Optimization in the Polyhedral Model".
+ */
+
+
+/* The schedule for an individual domain, plus information about the bands.
+ * In particular, we keep track of the number of bands and for each
+ * band, the starting position of the next band. The first band starts at
+ * position 0.
+ */
+struct isl_schedule_node {
+ isl_map *sched;
+ int n_band;
+ int *band_end;
+};
+
+/* Information about the computed schedule.
+ * n is the number of nodes/domains/statements.
+ * n_band is the maximal number of bands.
+ * n_total_row is the number of coordinates of the schedule.
+ * dim contains a description of the parameters.
+ */
+struct isl_schedule {
+ int n;
+ int n_band;
+ int n_total_row;
+ isl_dim *dim;
+
+ struct isl_schedule_node node[1];
+};
+
+/* Internal information about a node that is used during the construction
+ * of a schedule.
+ * dim represents the space in which the domain lives
+ * sched is a matrix representation of the schedule being constructed
+ * for this node
+ * sched_map is an isl_map representation of the same (partial) schedule
+ * sched_map may be NULL
+ * rank is the number of linearly independent rows in the linear part
+ * of sched
+ * the columns of cmap represent a change of basis for the schedule
+ * coefficients; the first rank columns span the linear part of
+ * the schedule rows
+ * start is the first variable in the LP problem in the sequences that
+ * represents the schedule coefficients of this node
+ * nvar is the dimension of the domain
+ * nparam is the number of parameters or 0 if we are not constructing
+ * a parametric schedule
+ *
+ * scc is the index of SCC (or WCC) this node belongs to
+ *
+ * band contains the band index for each of the rows of the schedule
+ *
+ * index, min_index and on_stack are used during the SCC detection
+ * index represents the order in which nodes are visited.
+ * min_index is the index of the root of a (sub)component.
+ * on_stack indicates whether the node is currently on the stack.
+ */
+struct isl_sched_node {
+ isl_dim *dim;
+ isl_mat *sched;
+ isl_map *sched_map;
+ int rank;
+ isl_mat *cmap;
+ int start;
+ int nvar;
+ int nparam;
+
+ int scc;
+
+ int *band;
+
+ /* scc detection */
+ int index;
+ int min_index;
+ int on_stack;
+};
+
+static int node_has_dim(const void *entry, const void *val)
+{
+ struct isl_sched_node *node = (struct isl_sched_node *)entry;
+ isl_dim *dim = (isl_dim *)val;
+
+ return isl_dim_equal(node->dim, dim);
+}
+
+/* An edge in the dependence graph. An edge may be used to
+ * ensure validity of the generated schedule, to minimize the dependence
+ * distance or both
+ *
+ * map is the dependence relation
+ * src is the source node
+ * dst is the sink node
+ * validity is set if the edge is used to ensure correctness
+ * proximity is set if the edge is used to minimize dependence distances
+ *
+ * For validity edges, start and end mark the sequence of inequality
+ * constraints in the LP problem that encode the validity constraint
+ * corresponding to this edge.
+ */
+struct isl_sched_edge {
+ isl_map *map;
+
+ struct isl_sched_node *src;
+ struct isl_sched_node *dst;
+
+ int validity;
+ int proximity;
+
+ int start;
+ int end;
+};
+
+/* Internal information about the dependence graph used during
+ * the construction of the schedule.
+ *
+ * intra_hmap is a cache, mapping dependence relations to their dual,
+ * for dependences from a node to itself
+ * inter_hmap is a cache, mapping dependence relations to their dual,
+ * for dependences between distinct nodes
+ *
+ * n is the number of nodes
+ * node is the list of nodes
+ * maxvar is the maximal number of variables over all nodes
+ * n_row is the current (maximal) number of linearly independent
+ * rows in the node schedules
+ * n_total_row is the current number of rows in the node schedules
+ * n_band is the current number of completed bands
+ * band_start is the starting row in the node schedules of the current band
+ * root is set if this graph is the original dependence graph,
+ * without any splitting
+ *
+ * sorted contains a list of node indices sorted according to the
+ * SCC to which a node belongs
+ *
+ * n_edge is the number of edges
+ * edge is the list of edges
+ * edge_table contains pointers into the edge array, hashed on the source
+ * and sink spaces; the table only contains edges that represent
+ * validity constraints (and that may or may not also represent proximity
+ * constraints)
+ *
+ * node_table contains pointers into the node array, hashed on the space
+ *
+ * region contains a list of variable sequences that should be non-trivial
+ *
+ * lp contains the (I)LP problem used to obtain new schedule rows
+ *
+ * src_scc and dst_scc are the source and sink SCCs of an edge with
+ * conflicting constraints
+ *
+ * scc, sp, index and stack are used during the detection of SCCs
+ * scc is the number of the next SCC
+ * stack contains the nodes on the path from the root to the current node
+ * sp is the stack pointer
+ * index is the index of the last node visited
+ */
+struct isl_sched_graph {
+ isl_hmap_map_basic_set *intra_hmap;
+ isl_hmap_map_basic_set *inter_hmap;
+
+ struct isl_sched_node *node;
+ int n;
+ int maxvar;
+ int n_row;
+
+ int *sorted;
+
+ int n_band;
+ int n_total_row;
+ int band_start;
+
+ int root;
+
+ struct isl_sched_edge *edge;
+ int n_edge;
+ struct isl_hash_table *edge_table;
+
+ struct isl_hash_table *node_table;
+ struct isl_region *region;
+
+ isl_basic_set *lp;
+
+ int src_scc;
+ int dst_scc;
+
+ /* scc detection */
+ int scc;
+ int sp;
+ int index;
+ int *stack;
+};
+
+/* Initialize node_table based on the list of nodes.
+ */
+static int graph_init_table(isl_ctx *ctx, struct isl_sched_graph *graph)
+{
+ int i;
+
+ graph->node_table = isl_hash_table_alloc(ctx, graph->n);
+ if (!graph->node_table)
+ return -1;
+
+ for (i = 0; i < graph->n; ++i) {
+ struct isl_hash_table_entry *entry;
+ uint32_t hash;
+
+ hash = isl_dim_get_hash(graph->node[i].dim);
+ entry = isl_hash_table_find(ctx, graph->node_table, hash,
+ &node_has_dim,
+ graph->node[i].dim, 1);
+ if (!entry)
+ return -1;
+ entry->data = &graph->node[i];
+ }
+
+ return 0;
+}
+
+/* Return a pointer to the node that lives within the given space,
+ * or NULL if there is no such node.
+ */
+static struct isl_sched_node *graph_find_node(isl_ctx *ctx,
+ struct isl_sched_graph *graph, __isl_keep isl_dim *dim)
+{
+ struct isl_hash_table_entry *entry;
+ uint32_t hash;
+
+ hash = isl_dim_get_hash(dim);
+ entry = isl_hash_table_find(ctx, graph->node_table, hash,
+ &node_has_dim, dim, 0);
+
+ return entry ? entry->data : NULL;
+}
+
+static int edge_has_src_and_dst(const void *entry, const void *val)
+{
+ const struct isl_sched_edge *edge = entry;
+ const struct isl_sched_edge *temp = val;
+
+ return edge->src == temp->src && edge->dst == temp->dst;
+}
+
+/* Initialize edge_table based on the list of edges.
+ * Only edges with validity set are added to the table.
+ */
+static int graph_init_edge_table(isl_ctx *ctx, struct isl_sched_graph *graph)
+{
+ int i;
+
+ graph->edge_table = isl_hash_table_alloc(ctx, graph->n_edge);
+ if (!graph->edge_table)
+ return -1;
+
+ for (i = 0; i < graph->n_edge; ++i) {
+ struct isl_hash_table_entry *entry;
+ uint32_t hash;
+
+ if (!graph->edge[i].validity)
+ continue;
+
+ hash = isl_hash_init();
+ hash = isl_hash_builtin(hash, graph->edge[i].src);
+ hash = isl_hash_builtin(hash, graph->edge[i].dst);
+ entry = isl_hash_table_find(ctx, graph->edge_table, hash,
+ &edge_has_src_and_dst,
+ &graph->edge[i], 1);
+ if (!entry)
+ return -1;
+ entry->data = &graph->edge[i];
+ }
+
+ return 0;
+}
+
+/* Check whether the dependence graph has a (validity) edge
+ * between the given two nodes.
+ */
+static int graph_has_edge(struct isl_sched_graph *graph,
+ struct isl_sched_node *src, struct isl_sched_node *dst)
+{
+ isl_ctx *ctx = isl_dim_get_ctx(src->dim);
+ struct isl_hash_table_entry *entry;
+ uint32_t hash;
+ struct isl_sched_edge temp = { .src = src, .dst = dst };
+ struct isl_sched_edge *edge;
+ int empty;
+
+ hash = isl_hash_init();
+ hash = isl_hash_builtin(hash, temp.src);
+ hash = isl_hash_builtin(hash, temp.dst);
+ entry = isl_hash_table_find(ctx, graph->edge_table, hash,
+ &edge_has_src_and_dst, &temp, 0);
+ if (!entry)
+ return 0;
+
+ edge = entry->data;
+ empty = isl_map_fast_is_empty(edge->map);
+ if (empty < 0)
+ return -1;
+
+ return !empty;
+}
+
+static int graph_alloc(isl_ctx *ctx, struct isl_sched_graph *graph,
+ int n_node, int n_edge)
+{
+ int i;
+
+ graph->n = n_node;
+ graph->n_edge = n_edge;
+ graph->node = isl_calloc_array(ctx, struct isl_sched_node, graph->n);
+ graph->sorted = isl_calloc_array(ctx, int, graph->n);
+ graph->region = isl_alloc_array(ctx, struct isl_region, graph->n);
+ graph->stack = isl_alloc_array(ctx, int, graph->n);
+ graph->edge = isl_calloc_array(ctx,
+ struct isl_sched_edge, graph->n_edge);
+
+ graph->intra_hmap = isl_hmap_map_basic_set_alloc(ctx, 2 * n_edge);
+ graph->inter_hmap = isl_hmap_map_basic_set_alloc(ctx, 2 * n_edge);
+
+ if (!graph->node || !graph->region || !graph->stack || !graph->edge ||
+ !graph->sorted)
+ return -1;
+
+ for(i = 0; i < graph->n; ++i)
+ graph->sorted[i] = i;
+
+ return 0;
+}
+
+static void graph_free(isl_ctx *ctx, struct isl_sched_graph *graph)
+{
+ int i;
+
+ isl_hmap_map_basic_set_free(ctx, graph->intra_hmap);
+ isl_hmap_map_basic_set_free(ctx, graph->inter_hmap);
+
+ for (i = 0; i < graph->n; ++i) {
+ isl_dim_free(graph->node[i].dim);
+ isl_mat_free(graph->node[i].sched);
+ isl_map_free(graph->node[i].sched_map);
+ isl_mat_free(graph->node[i].cmap);
+ if (graph->root)
+ free(graph->node[i].band);
+ }
+ free(graph->node);
+ free(graph->sorted);
+ for (i = 0; i < graph->n_edge; ++i)
+ isl_map_free(graph->edge[i].map);
+ free(graph->edge);
+ free(graph->region);
+ free(graph->stack);
+ isl_hash_table_free(ctx, graph->edge_table);
+ isl_hash_table_free(ctx, graph->node_table);
+ isl_basic_set_free(graph->lp);
+}
+
+/* Add a new node to the graph representing the given set.
+ */
+static int extract_node(__isl_take isl_set *set, void *user)
+{
+ int i;
+ int nvar, nparam;
+ isl_ctx *ctx;
+ isl_dim *dim;
+ isl_mat *sched;
+ struct isl_sched_graph *graph = user;
+ int *band;
+
+ ctx = isl_set_get_ctx(set);
+ dim = isl_set_get_dim(set);
+ isl_set_free(set);
+ nvar = isl_dim_size(dim, isl_dim_set);
+ nparam = isl_dim_size(dim, isl_dim_param);
+ if (!ctx->opt->schedule_parametric)
+ nparam = 0;
+ sched = isl_mat_alloc(ctx, 0, 1 + nparam + nvar);
+ graph->node[graph->n].dim = dim;
+ graph->node[graph->n].nvar = nvar;
+ graph->node[graph->n].nparam = nparam;
+ graph->node[graph->n].sched = sched;
+ graph->node[graph->n].sched_map = NULL;
+ band = isl_alloc_array(ctx, int, graph->n_edge + nvar);
+ graph->node[graph->n].band = band;
+ graph->n++;
+
+ if (!sched || !band)
+ return -1;
+
+ return 0;
+}
+
+/* Add a new edge to the graph based on the given map.
+ * Edges are first extracted from the validity dependences,
+ * from which the edge_table is constructed.
+ * Afterwards, the proximity dependences are added. If a proximity
+ * dependence relation happens to be identical to one of the
+ * validity dependence relations added before, then we don't create
+ * a new edge, but instead mark the original edge as also representing
+ * a proximity dependence.
+ */
+static int extract_edge(__isl_take isl_map *map, void *user)
+{
+ isl_ctx *ctx = isl_map_get_ctx(map);
+ struct isl_sched_graph *graph = user;
+ struct isl_sched_node *src, *dst;
+ isl_dim *dim;
+
+ dim = isl_dim_domain(isl_map_get_dim(map));
+ src = graph_find_node(ctx, graph, dim);
+ isl_dim_free(dim);
+ dim = isl_dim_range(isl_map_get_dim(map));
+ dst = graph_find_node(ctx, graph, dim);
+ isl_dim_free(dim);
+
+ if (!src || !dst) {
+ isl_map_free(map);
+ return 0;
+ }
+
+ graph->edge[graph->n_edge].src = src;
+ graph->edge[graph->n_edge].dst = dst;
+ graph->edge[graph->n_edge].map = map;
+ graph->edge[graph->n_edge].validity = !graph->edge_table;
+ graph->edge[graph->n_edge].proximity = !!graph->edge_table;
+ graph->n_edge++;
+
+ if (graph->edge_table) {
+ uint32_t hash;
+ struct isl_hash_table_entry *entry;
+ struct isl_sched_edge *edge;
+ int is_equal;
+
+ hash = isl_hash_init();
+ hash = isl_hash_builtin(hash, src);
+ hash = isl_hash_builtin(hash, dst);
+ entry = isl_hash_table_find(ctx, graph->edge_table, hash,
+ &edge_has_src_and_dst,
+ &graph->edge[graph->n_edge - 1], 0);
+ if (!entry)
+ return 0;
+ edge = entry->data;
+ is_equal = isl_map_fast_is_equal(map, edge->map);
+ if (is_equal < 0)
+ return -1;
+ if (!is_equal)
+ return 0;
+
+ graph->n_edge--;
+ edge->proximity = 1;
+ isl_map_free(map);
+ }
+
+ return 0;
+}
+
+/* Check whether there is a validity dependence from src to dst,
+ * forcing dst to follow src.
+ */
+static int node_follows(struct isl_sched_graph *graph,
+ struct isl_sched_node *dst, struct isl_sched_node *src)
+{
+ return graph_has_edge(graph, src, dst);
+}
+
+/* Perform Tarjan's algorithm for computing the strongly connected components
+ * in the dependence graph (only validity edges).
+ * If directed is not set, we consider the graph to be undirected and
+ * we effectively compute the (weakly) connected components.
+ */
+static int detect_sccs_tarjan(struct isl_sched_graph *g, int i, int directed)
+{
+ int j;
+
+ g->node[i].index = g->index;
+ g->node[i].min_index = g->index;
+ g->node[i].on_stack = 1;
+ g->index++;
+ g->stack[g->sp++] = i;
+
+ for (j = g->n - 1; j >= 0; --j) {
+ int f;
+
+ if (j == i)
+ continue;
+ if (g->node[j].index >= 0 &&
+ (!g->node[j].on_stack ||
+ g->node[j].index > g->node[i].min_index))
+ continue;
+
+ f = node_follows(g, &g->node[i], &g->node[j]);
+ if (f < 0)
+ return -1;
+ if (!f && !directed) {
+ f = node_follows(g, &g->node[j], &g->node[i]);
+ if (f < 0)
+ return -1;
+ }
+ if (!f)
+ continue;
+ if (g->node[j].index < 0) {
+ detect_sccs_tarjan(g, j, directed);
+ if (g->node[j].min_index < g->node[i].min_index)
+ g->node[i].min_index = g->node[j].min_index;
+ } else if (g->node[j].index < g->node[i].min_index)
+ g->node[i].min_index = g->node[j].index;
+ }
+
+ if (g->node[i].index != g->node[i].min_index)
+ return 0;
+
+ do {
+ j = g->stack[--g->sp];
+ g->node[j].on_stack = 0;
+ g->node[j].scc = g->scc;
+ } while (j != i);
+ g->scc++;
+
+ return 0;
+}
+
+static int detect_ccs(struct isl_sched_graph *graph, int directed)
+{
+ int i;
+
+ graph->index = 0;
+ graph->sp = 0;
+ graph->scc = 0;
+ for (i = graph->n - 1; i >= 0; --i)
+ graph->node[i].index = -1;
+
+ for (i = graph->n - 1; i >= 0; --i) {
+ if (graph->node[i].index >= 0)
+ continue;
+ if (detect_sccs_tarjan(graph, i, directed) < 0)
+ return -1;
+ }
+
+ return 0;
+}
+
+/* Apply Tarjan's algorithm to detect the strongly connected components
+ * in the dependence graph.
+ */
+static int detect_sccs(struct isl_sched_graph *graph)
+{
+ return detect_ccs(graph, 1);
+}
+
+/* Apply Tarjan's algorithm to detect the (weakly) connected components
+ * in the dependence graph.
+ */
+static int detect_wccs(struct isl_sched_graph *graph)
+{
+ return detect_ccs(graph, 0);
+}
+
+static int cmp_scc(const void *a, const void *b, void *data)
+{
+ struct isl_sched_graph *graph = data;
+ const int *i1 = a;
+ const int *i2 = b;
+
+ return graph->node[*i1].scc - graph->node[*i2].scc;
+}
+
+/* Sort the elements of graph->sorted according to the corresponding SCCs.
+ */
+static void sort_sccs(struct isl_sched_graph *graph)
+{
+ isl_quicksort(graph->sorted, graph->n, sizeof(int), &cmp_scc, graph);
+}
+
+/* Given a dependence relation R from a node to itself,
+ * construct the set of coefficients of valid constraints for elements
+ * in that dependence relation.
+ * In particular, the result contains tuples of coefficients
+ * c_0, c_n, c_x such that
+ *
+ * c_0 + c_n n + c_x y - c_x x >= 0 for each (x,y) in R
+ *
+ * or, equivalently,
+ *
+ * c_0 + c_n n + c_x d >= 0 for each d in delta R = { y - x | (x,y) in R }
+ *
+ * We choose here to compute the dual of delta R.
+ * Alternatively, we could have computed the dual of R, resulting
+ * in a set of tuples c_0, c_n, c_x, c_y, and then
+ * plugged in (c_0, c_n, c_x, -c_x).
+ */
+static __isl_give isl_basic_set *intra_coefficients(
+ struct isl_sched_graph *graph, __isl_take isl_map *map)
+{
+ isl_ctx *ctx = isl_map_get_ctx(map);
+ isl_set *delta;
+ isl_basic_set *coef;
+
+ if (isl_hmap_map_basic_set_has(ctx, graph->intra_hmap, map))
+ return isl_hmap_map_basic_set_get(ctx, graph->intra_hmap, map);
+
+ delta = isl_set_remove_divs(isl_map_deltas(isl_map_copy(map)));
+ coef = isl_set_coefficients(delta);
+ isl_hmap_map_basic_set_set(ctx, graph->intra_hmap, map,
+ isl_basic_set_copy(coef));
+
+ return coef;
+}
+
+/* Given a dependence relation R, * construct the set of coefficients
+ * of valid constraints for elements in that dependence relation.
+ * In particular, the result contains tuples of coefficients
+ * c_0, c_n, c_x, c_y such that
+ *
+ * c_0 + c_n n + c_x x + c_y y >= 0 for each (x,y) in R
+ *
+ */
+static __isl_give isl_basic_set *inter_coefficients(
+ struct isl_sched_graph *graph, __isl_take isl_map *map)
+{
+ isl_ctx *ctx = isl_map_get_ctx(map);
+ isl_set *set;
+ isl_basic_set *coef;
+
+ if (isl_hmap_map_basic_set_has(ctx, graph->inter_hmap, map))
+ return isl_hmap_map_basic_set_get(ctx, graph->inter_hmap, map);
+
+ set = isl_map_wrap(isl_map_remove_divs(isl_map_copy(map)));
+ coef = isl_set_coefficients(set);
+ isl_hmap_map_basic_set_set(ctx, graph->inter_hmap, map,
+ isl_basic_set_copy(coef));
+
+ return coef;
+}
+
+/* Add constraints to graph->lp that force validity for the given
+ * dependence from a node i to itself.
+ * That is, add constraints that enforce
+ *
+ * (c_i_0 + c_i_n n + c_i_x y) - (c_i_0 + c_i_n n + c_i_x x)
+ * = c_i_x (y - x) >= 0
+ *
+ * for each (x,y) in R.
+ * We obtain general constraints on coefficients (c_0, c_n, c_x)
+ * of valid constraints for (y - x) and then plug in (0, 0, c_i_x^+ - c_i_x^-),
+ * where c_i_x = c_i_x^+ - c_i_x^-, with c_i_x^+ and c_i_x^- non-negative.
+ * In graph->lp, the c_i_x^- appear before their c_i_x^+ counterpart.
+ *
+ * Actually, we do not construct constraints for the c_i_x themselves,
+ * but for the coefficients of c_i_x written as a linear combination
+ * of the columns in node->cmap.
+ */
+static int add_intra_validity_constraints(struct isl_sched_graph *graph,
+ struct isl_sched_edge *edge)
+{
+ unsigned total;
+ isl_map *map = isl_map_copy(edge->map);
+ isl_ctx *ctx = isl_map_get_ctx(map);
+ isl_dim *dim;
+ isl_dim_map *dim_map;
+ isl_basic_set *coef;
+ struct isl_sched_node *node = edge->src;
+
+ coef = intra_coefficients(graph, map);
+
+ dim = isl_dim_domain(isl_dim_unwrap(isl_basic_set_get_dim(coef)));
+
+ coef = isl_basic_set_transform_dims(coef, isl_dim_set,
+ isl_dim_size(dim, isl_dim_set), isl_mat_copy(node->cmap));
+
+ total = isl_basic_set_total_dim(graph->lp);
+ dim_map = isl_dim_map_alloc(ctx, total);
+ isl_dim_map_range(dim_map, node->start + 2 * node->nparam + 1, 2,
+ isl_dim_size(dim, isl_dim_set), 1,
+ node->nvar, -1);
+ isl_dim_map_range(dim_map, node->start + 2 * node->nparam + 2, 2,
+ isl_dim_size(dim, isl_dim_set), 1,
+ node->nvar, 1);
+ graph->lp = isl_basic_set_extend_constraints(graph->lp,
+ coef->n_eq, coef->n_ineq);
+ graph->lp = isl_basic_set_add_constraints_dim_map(graph->lp,
+ coef, dim_map);
+ isl_dim_free(dim);
+
+ return 0;
+}
+
+/* Add constraints to graph->lp that force validity for the given
+ * dependence from node i to node j.
+ * That is, add constraints that enforce
+ *
+ * (c_j_0 + c_j_n n + c_j_x y) - (c_i_0 + c_i_n n + c_i_x x) >= 0
+ *
+ * for each (x,y) in R.
+ * We obtain general constraints on coefficients (c_0, c_n, c_x, c_y)
+ * of valid constraints for R and then plug in
+ * (c_j_0 - c_i_0, c_j_n^+ - c_j_n^- - (c_i_n^+ - c_i_n^-),
+ * c_j_x^+ - c_j_x^- - (c_i_x^+ - c_i_x^-)),
+ * where c_* = c_*^+ - c_*^-, with c_*^+ and c_*^- non-negative.
+ * In graph->lp, the c_*^- appear before their c_*^+ counterpart.
+ *
+ * Actually, we do not construct constraints for the c_*_x themselves,
+ * but for the coefficients of c_*_x written as a linear combination
+ * of the columns in node->cmap.
+ */
+static int add_inter_validity_constraints(struct isl_sched_graph *graph,
+ struct isl_sched_edge *edge)
+{
+ unsigned total;
+ isl_map *map = isl_map_copy(edge->map);
+ isl_ctx *ctx = isl_map_get_ctx(map);
+ isl_dim *dim;
+ isl_dim_map *dim_map;
+ isl_basic_set *coef;
+ struct isl_sched_node *src = edge->src;
+ struct isl_sched_node *dst = edge->dst;
+
+ coef = inter_coefficients(graph, map);
+
+ dim = isl_dim_domain(isl_dim_unwrap(isl_basic_set_get_dim(coef)));
+
+ coef = isl_basic_set_transform_dims(coef, isl_dim_set,
+ isl_dim_size(dim, isl_dim_set), isl_mat_copy(src->cmap));
+ coef = isl_basic_set_transform_dims(coef, isl_dim_set,
+ isl_dim_size(dim, isl_dim_set) + src->nvar,
+ isl_mat_copy(dst->cmap));
+
+ total = isl_basic_set_total_dim(graph->lp);
+ dim_map = isl_dim_map_alloc(ctx, total);
+
+ isl_dim_map_range(dim_map, dst->start, 0, 0, 0, 1, 1);
+ isl_dim_map_range(dim_map, dst->start + 1, 2, 1, 1, dst->nparam, -1);
+ isl_dim_map_range(dim_map, dst->start + 2, 2, 1, 1, dst->nparam, 1);
+ isl_dim_map_range(dim_map, dst->start + 2 * dst->nparam + 1, 2,
+ isl_dim_size(dim, isl_dim_set) + src->nvar, 1,
+ dst->nvar, -1);
+ isl_dim_map_range(dim_map, dst->start + 2 * dst->nparam + 2, 2,
+ isl_dim_size(dim, isl_dim_set) + src->nvar, 1,
+ dst->nvar, 1);
+
+ isl_dim_map_range(dim_map, src->start, 0, 0, 0, 1, -1);
+ isl_dim_map_range(dim_map, src->start + 1, 2, 1, 1, src->nparam, 1);
+ isl_dim_map_range(dim_map, src->start + 2, 2, 1, 1, src->nparam, -1);
+ isl_dim_map_range(dim_map, src->start + 2 * src->nparam + 1, 2,
+ isl_dim_size(dim, isl_dim_set), 1,
+ src->nvar, 1);
+ isl_dim_map_range(dim_map, src->start + 2 * src->nparam + 2, 2,
+ isl_dim_size(dim, isl_dim_set), 1,
+ src->nvar, -1);
+
+ edge->start = graph->lp->n_ineq;
+ graph->lp = isl_basic_set_extend_constraints(graph->lp,
+ coef->n_eq, coef->n_ineq);
+ graph->lp = isl_basic_set_add_constraints_dim_map(graph->lp,
+ coef, dim_map);
+ isl_dim_free(dim);
+ edge->end = graph->lp->n_ineq;
+
+ return 0;
+}
+
+/* Add constraints to graph->lp that bound the dependence distance for the given
+ * dependence from a node i to itself.
+ * If s = 1, we add the constraint
+ *
+ * c_i_x (y - x) <= m_0 + m_n n
+ *
+ * or
+ *
+ * -c_i_x (y - x) + m_0 + m_n n >= 0
+ *
+ * for each (x,y) in R.
+ * If s = -1, we add the constraint
+ *
+ * -c_i_x (y - x) <= m_0 + m_n n
+ *
+ * or
+ *
+ * c_i_x (y - x) + m_0 + m_n n >= 0
+ *
+ * for each (x,y) in R.
+ * We obtain general constraints on coefficients (c_0, c_n, c_x)
+ * of valid constraints for (y - x) and then plug in (m_0, m_n, -s * c_i_x),
+ * with each coefficient (except m_0) represented as a pair of non-negative
+ * coefficients.
+ *
+ * Actually, we do not construct constraints for the c_i_x themselves,
+ * but for the coefficients of c_i_x written as a linear combination
+ * of the columns in node->cmap.
+ */
+static int add_intra_proximity_constraints(struct isl_sched_graph *graph,
+ struct isl_sched_edge *edge, int s)
+{
+ unsigned total;
+ unsigned nparam;
+ isl_map *map = isl_map_copy(edge->map);
+ isl_ctx *ctx = isl_map_get_ctx(map);
+ isl_dim *dim;
+ isl_dim_map *dim_map;
+ isl_set *delta;
+ isl_basic_set *coef;
+ struct isl_sched_node *node = edge->src;
+
+ coef = intra_coefficients(graph, map);
+
+ dim = isl_dim_domain(isl_dim_unwrap(isl_basic_set_get_dim(coef)));
+
+ coef = isl_basic_set_transform_dims(coef, isl_dim_set,
+ isl_dim_size(dim, isl_dim_set), isl_mat_copy(node->cmap));
+
+ nparam = isl_dim_size(node->dim, isl_dim_param);
+ total = isl_basic_set_total_dim(graph->lp);
+ dim_map = isl_dim_map_alloc(ctx, total);
+ isl_dim_map_range(dim_map, 1, 0, 0, 0, 1, 1);
+ isl_dim_map_range(dim_map, 4, 2, 1, 1, nparam, -1);
+ isl_dim_map_range(dim_map, 5, 2, 1, 1, nparam, 1);
+ isl_dim_map_range(dim_map, node->start + 2 * node->nparam + 1, 2,
+ isl_dim_size(dim, isl_dim_set), 1,
+ node->nvar, s);
+ isl_dim_map_range(dim_map, node->start + 2 * node->nparam + 2, 2,
+ isl_dim_size(dim, isl_dim_set), 1,
+ node->nvar, -s);
+ graph->lp = isl_basic_set_extend_constraints(graph->lp,
+ coef->n_eq, coef->n_ineq);
+ graph->lp = isl_basic_set_add_constraints_dim_map(graph->lp,
+ coef, dim_map);
+ isl_dim_free(dim);
+
+ return 0;
+}
+
+/* Add constraints to graph->lp that bound the dependence distance for the given
+ * dependence from node i to node j.
+ * If s = 1, we add the constraint
+ *
+ * (c_j_0 + c_j_n n + c_j_x y) - (c_i_0 + c_i_n n + c_i_x x)
+ * <= m_0 + m_n n
+ *
+ * or
+ *
+ * -(c_j_0 + c_j_n n + c_j_x y) + (c_i_0 + c_i_n n + c_i_x x) +
+ * m_0 + m_n n >= 0
+ *
+ * for each (x,y) in R.
+ * If s = -1, we add the constraint
+ *
+ * -((c_j_0 + c_j_n n + c_j_x y) - (c_i_0 + c_i_n n + c_i_x x))
+ * <= m_0 + m_n n
+ *
+ * or
+ *
+ * (c_j_0 + c_j_n n + c_j_x y) - (c_i_0 + c_i_n n + c_i_x x) +
+ * m_0 + m_n n >= 0
+ *
+ * for each (x,y) in R.
+ * We obtain general constraints on coefficients (c_0, c_n, c_x, c_y)
+ * of valid constraints for R and then plug in
+ * (m_0 - s*c_j_0 + s*c_i_0, m_n - s*c_j_n + s*c_i_n,
+ * -s*c_j_x+s*c_i_x)
+ * with each coefficient (except m_0, c_j_0 and c_i_0)
+ * represented as a pair of non-negative coefficients.
+ *
+ * Actually, we do not construct constraints for the c_*_x themselves,
+ * but for the coefficients of c_*_x written as a linear combination
+ * of the columns in node->cmap.
+ */
+static int add_inter_proximity_constraints(struct isl_sched_graph *graph,
+ struct isl_sched_edge *edge, int s)
+{
+ unsigned total;
+ unsigned nparam;
+ isl_map *map = isl_map_copy(edge->map);
+ isl_ctx *ctx = isl_map_get_ctx(map);
+ isl_dim *dim;
+ isl_dim_map *dim_map;
+ isl_basic_set *coef;
+ struct isl_sched_node *src = edge->src;
+ struct isl_sched_node *dst = edge->dst;
+
+ coef = inter_coefficients(graph, map);
+
+ dim = isl_dim_domain(isl_dim_unwrap(isl_basic_set_get_dim(coef)));
+
+ coef = isl_basic_set_transform_dims(coef, isl_dim_set,
+ isl_dim_size(dim, isl_dim_set), isl_mat_copy(src->cmap));
+ coef = isl_basic_set_transform_dims(coef, isl_dim_set,
+ isl_dim_size(dim, isl_dim_set) + src->nvar,
+ isl_mat_copy(dst->cmap));
+
+ nparam = isl_dim_size(src->dim, isl_dim_param);
+ total = isl_basic_set_total_dim(graph->lp);
+ dim_map = isl_dim_map_alloc(ctx, total);
+
+ isl_dim_map_range(dim_map, 1, 0, 0, 0, 1, 1);
+ isl_dim_map_range(dim_map, 4, 2, 1, 1, nparam, -1);
+ isl_dim_map_range(dim_map, 5, 2, 1, 1, nparam, 1);
+
+ isl_dim_map_range(dim_map, dst->start, 0, 0, 0, 1, -s);
+ isl_dim_map_range(dim_map, dst->start + 1, 2, 1, 1, dst->nparam, s);
+ isl_dim_map_range(dim_map, dst->start + 2, 2, 1, 1, dst->nparam, -s);
+ isl_dim_map_range(dim_map, dst->start + 2 * dst->nparam + 1, 2,
+ isl_dim_size(dim, isl_dim_set) + src->nvar, 1,
+ dst->nvar, s);
+ isl_dim_map_range(dim_map, dst->start + 2 * dst->nparam + 2, 2,
+ isl_dim_size(dim, isl_dim_set) + src->nvar, 1,
+ dst->nvar, -s);
+
+ isl_dim_map_range(dim_map, src->start, 0, 0, 0, 1, s);
+ isl_dim_map_range(dim_map, src->start + 1, 2, 1, 1, src->nparam, -s);
+ isl_dim_map_range(dim_map, src->start + 2, 2, 1, 1, src->nparam, s);
+ isl_dim_map_range(dim_map, src->start + 2 * src->nparam + 1, 2,
+ isl_dim_size(dim, isl_dim_set), 1,
+ src->nvar, -s);
+ isl_dim_map_range(dim_map, src->start + 2 * src->nparam + 2, 2,
+ isl_dim_size(dim, isl_dim_set), 1,
+ src->nvar, s);
+
+ graph->lp = isl_basic_set_extend_constraints(graph->lp,
+ coef->n_eq, coef->n_ineq);
+ graph->lp = isl_basic_set_add_constraints_dim_map(graph->lp,
+ coef, dim_map);
+ isl_dim_free(dim);
+
+ return 0;
+}
+
+static int add_all_validity_constraints(struct isl_sched_graph *graph)
+{
+ int i;
+
+ for (i = 0; i < graph->n_edge; ++i) {
+ struct isl_sched_edge *edge= &graph->edge[i];
+ if (!edge->validity)
+ continue;
+ if (edge->src != edge->dst)
+ continue;
+ if (add_intra_validity_constraints(graph, edge) < 0)
+ return -1;
+ }
+
+ for (i = 0; i < graph->n_edge; ++i) {
+ struct isl_sched_edge *edge = &graph->edge[i];
+ if (!edge->validity)
+ continue;
+ if (edge->src == edge->dst)
+ continue;
+ if (add_inter_validity_constraints(graph, edge) < 0)
+ return -1;
+ }
+
+ return 0;
+}
+
+/* Add constraints to graph->lp that bound the dependence distance
+ * for all dependence relations.
+ * If a given proximity dependence is identical to a validity
+ * dependence, then the dependence distance is already bounded
+ * from below (by zero), so we only need to bound the distance
+ * from above.
+ * Otherwise, we need to bound the distance both from above and from below.
+ */
+static int add_all_proximity_constraints(struct isl_sched_graph *graph)
+{
+ int i;
+
+ for (i = 0; i < graph->n_edge; ++i) {
+ struct isl_sched_edge *edge= &graph->edge[i];
+ if (!edge->proximity)
+ continue;
+ if (edge->src == edge->dst &&
+ add_intra_proximity_constraints(graph, edge, 1) < 0)
+ return -1;
+ if (edge->src != edge->dst &&
+ add_inter_proximity_constraints(graph, edge, 1) < 0)
+ return -1;
+ if (edge->validity)
+ continue;
+ if (edge->src == edge->dst &&
+ add_intra_proximity_constraints(graph, edge, -1) < 0)
+ return -1;
+ if (edge->src != edge->dst &&
+ add_inter_proximity_constraints(graph, edge, -1) < 0)
+ return -1;
+ }
+
+ return 0;
+}
+
+/* Compute a basis for the rows in the linear part of the schedule
+ * and extend this basis to a full basis. The remaining rows
+ * can then be used to force linear independence from the rows
+ * in the schedule.
+ *
+ * In particular, given the schedule rows S, we compute
+ *
+ * S = H Q
+ *
+ * with H the Hermite normal form of S. That is, all but the
+ * first rank columns of Q are zero and so each row in S is
+ * a linear combination of the first rank rows of Q.
+ * The matrix Q is then transposed because we will write the
+ * coefficients of the next schedule row as a column vector s
+ * and express this s as a linear combination s = Q c of the
+ * computed basis.
+ */
+static int node_update_cmap(struct isl_sched_node *node)
+{
+ isl_mat *H, *Q;
+ int n_row = isl_mat_rows(node->sched);
+
+ H = isl_mat_sub_alloc(node->sched, 0, n_row,
+ 1 + node->nparam, node->nvar);
+
+ H = isl_mat_left_hermite(H, 0, NULL, &Q);
+ isl_mat_free(node->cmap);
+ node->cmap = isl_mat_transpose(Q);
+ node->rank = isl_mat_initial_non_zero_cols(H);
+ isl_mat_free(H);
+
+ if (!node->cmap || node->rank < 0)
+ return -1;
+ return 0;
+}
+
+/* Count the number of equality and inequality constraints
+ * that will be added. If once is set, then we count
+ * each edge exactly once. Otherwise, we count as follows
+ * validity -> 1 (>= 0)
+ * validity+proximity -> 2 (>= 0 and upper bound)
+ * proximity -> 2 (lower and upper bound)
+ */
+static int count_constraints(struct isl_sched_graph *graph,
+ int *n_eq, int *n_ineq, int once)
+{
+ int i;
+ isl_basic_set *coef;
+
+ *n_eq = *n_ineq = 0;
+ for (i = 0; i < graph->n_edge; ++i) {
+ struct isl_sched_edge *edge= &graph->edge[i];
+ isl_map *map = isl_map_copy(edge->map);
+ int f = once ? 1 : edge->proximity ? 2 : 1;
+
+ if (edge->src == edge->dst)
+ coef = intra_coefficients(graph, map);
+ else
+ coef = inter_coefficients(graph, map);
+ if (!coef)
+ return -1;
+ *n_eq += f * coef->n_eq;
+ *n_ineq += f * coef->n_ineq;
+ isl_basic_set_free(coef);
+ }
+
+ return 0;
+}
+
+/* Construct an ILP problem for finding schedule coefficients
+ * that result in non-negative, but small dependence distances
+ * over all dependences.
+ * In particular, the dependence distances over proximity edges
+ * are bounded by m_0 + m_n n and we compute schedule coefficients
+ * with small values (preferably zero) of m_n and m_0.
+ *
+ * All variables of the ILP are non-negative. The actual coefficients
+ * may be negative, so each coefficient is represented as the difference
+ * of two non-negative variables. The negative part always appears
+ * immediately before the positive part.
+ * Other than that, the variables have the following order
+ *
+ * - sum of positive and negative parts of m_n coefficients
+ * - m_0
+ * - sum of positive and negative parts of all c_n coefficients
+ * (unconstrained when computing non-parametric schedules)
+ * - sum of positive and negative parts of all c_x coefficients
+ * - positive and negative parts of m_n coefficients
+ * - for each node
+ * - c_i_0
+ * - positive and negative parts of c_i_n (if parametric)
+ * - positive and negative parts of c_i_x
+ *
+ * The c_i_x are not represented directly, but through the columns of
+ * node->cmap. That is, the computed values are for variable t_i_x
+ * such that c_i_x = Q t_i_x with Q equal to node->cmap.
+ *
+ * The constraints are those from the edges plus two or three equalities
+ * to express the sums.
+ */
+static int setup_lp(isl_ctx *ctx, struct isl_sched_graph *graph)
+{
+ int i, j;
+ int k;
+ unsigned nparam;
+ unsigned total;
+ isl_dim *dim;
+ int parametric;
+ int param_pos;
+ int n_eq, n_ineq;
+
+ parametric = ctx->opt->schedule_parametric;
+ nparam = isl_dim_size(graph->node[0].dim, isl_dim_param);
+ param_pos = 4;
+ total = param_pos + 2 * nparam;
+ for (i = 0; i < graph->n; ++i) {
+ struct isl_sched_node *node = &graph->node[graph->sorted[i]];
+ if (node_update_cmap(node) < 0)
+ return -1;
+ node->start = total;
+ total += 1 + 2 * (node->nparam + node->nvar);
+ }
+
+ if (count_constraints(graph, &n_eq, &n_ineq, 0) < 0)
+ return -1;
+
+ dim = isl_dim_set_alloc(ctx, 0, total);
+ isl_basic_set_free(graph->lp);
+ n_eq += 2 + parametric;
+ graph->lp = isl_basic_set_alloc_dim(dim, 0, n_eq, n_ineq);
+
+ k = isl_basic_set_alloc_equality(graph->lp);
+ if (k < 0)
+ return -1;
+ isl_seq_clr(graph->lp->eq[k], 1 + total);
+ isl_int_set_si(graph->lp->eq[k][1], -1);
+ for (i = 0; i < 2 * nparam; ++i)
+ isl_int_set_si(graph->lp->eq[k][1 + param_pos + i], 1);
+
+ if (parametric) {
+ k = isl_basic_set_alloc_equality(graph->lp);
+ if (k < 0)
+ return -1;
+ isl_seq_clr(graph->lp->eq[k], 1 + total);
+ isl_int_set_si(graph->lp->eq[k][3], -1);
+ for (i = 0; i < graph->n; ++i) {
+ int pos = 1 + graph->node[i].start + 1;
+
+ for (j = 0; j < 2 * graph->node[i].nparam; ++j)
+ isl_int_set_si(graph->lp->eq[k][pos + j], 1);
+ }
+ }
+
+ k = isl_basic_set_alloc_equality(graph->lp);
+ if (k < 0)
+ return -1;
+ isl_seq_clr(graph->lp->eq[k], 1 + total);
+ isl_int_set_si(graph->lp->eq[k][4], -1);
+ for (i = 0; i < graph->n; ++i) {
+ struct isl_sched_node *node = &graph->node[i];
+ int pos = 1 + node->start + 1 + 2 * node->nparam;
+
+ for (j = 0; j < 2 * node->nvar; ++j)
+ isl_int_set_si(graph->lp->eq[k][pos + j], 1);
+ }
+
+ if (add_all_validity_constraints(graph) < 0)
+ return -1;
+ if (add_all_proximity_constraints(graph) < 0)
+ return -1;
+
+ return 0;
+}
+
+/* Analyze the conflicting constraint found by
+ * isl_tab_basic_set_non_trivial_lexmin. If it corresponds to the validity
+ * constraint of one of the edges between distinct nodes, living, moreover
+ * in distinct SCCs, then record the source and sink SCC as this may
+ * be a good place to cut between SCCs.
+ */
+static int check_conflict(int con, void *user)
+{
+ int i;
+ struct isl_sched_graph *graph = user;
+
+ if (graph->src_scc >= 0)
+ return 0;
+
+ con -= graph->lp->n_eq;
+
+ if (con >= graph->lp->n_ineq)
+ return 0;
+
+ for (i = 0; i < graph->n_edge; ++i) {
+ if (!graph->edge[i].validity)
+ continue;
+ if (graph->edge[i].src == graph->edge[i].dst)
+ continue;
+ if (graph->edge[i].src->scc == graph->edge[i].dst->scc)
+ continue;
+ if (graph->edge[i].start > con)
+ continue;
+ if (graph->edge[i].end <= con)
+ continue;
+ graph->src_scc = graph->edge[i].src->scc;
+ graph->dst_scc = graph->edge[i].dst->scc;
+ }
+
+ return 0;
+}
+
+/* Check whether the next schedule row of the given node needs to be
+ * non-trivial. Lower-dimensional domains may have some trivial rows,
+ * but as soon as the number of remaining required non-trivial rows
+ * is as large as the number or remaining rows to be computed,
+ * all remaining rows need to be non-trivial.
+ */
+static int needs_row(struct isl_sched_graph *graph, struct isl_sched_node *node)
+{
+ return node->nvar - node->rank >= graph->maxvar - graph->n_row;
+}
+
+/* Solve the ILP problem constructed in setup_lp.
+ * For each node such that all the remaining rows of its schedule
+ * need to be non-trivial, we construct a non-triviality region.
+ * This region imposes that the next row is independent of previous rows.
+ * In particular the coefficients c_i_x are represented by t_i_x
+ * variables with c_i_x = Q t_i_x and Q a unimodular matrix such that
+ * its first columns span the rows of the previously computed part
+ * of the schedule. The non-triviality region enforces that at least
+ * one of the remaining components of t_i_x is non-zero, i.e.,
+ * that the new schedule row depends on at least one of the remaining
+ * columns of Q.
+ */
+static __isl_give isl_vec *solve_lp(struct isl_sched_graph *graph)
+{
+ int i;
+ isl_vec *sol;
+ isl_basic_set *lp;
+
+ for (i = 0; i < graph->n; ++i) {
+ struct isl_sched_node *node = &graph->node[i];
+ int skip = node->rank;
+ graph->region[i].pos = node->start + 1 + 2*(node->nparam+skip);
+ if (needs_row(graph, node))
+ graph->region[i].len = 2 * (node->nvar - skip);
+ else
+ graph->region[i].len = 0;
+ }
+ lp = isl_basic_set_copy(graph->lp);
+ sol = isl_tab_basic_set_non_trivial_lexmin(lp, 2, graph->n,
+ graph->region, &check_conflict, graph);
+ return sol;
+}
+
+/* Update the schedules of all nodes based on the given solution
+ * of the LP problem.
+ * The new row is added to the current band.
+ * All possibly negative coefficients are encoded as a difference
+ * of two non-negative variables, so we need to perform the subtraction
+ * here. Moreover, if use_cmap is set, then the solution does
+ * not refer to the actual coefficients c_i_x, but instead to variables
+ * t_i_x such that c_i_x = Q t_i_x and Q is equal to node->cmap.
+ * In this case, we then also need to perform this multiplication
+ * to obtain the values of c_i_x.
+ */
+static int update_schedule(struct isl_sched_graph *graph,
+ __isl_take isl_vec *sol, int use_cmap)
+{
+ int i, j;
+ isl_vec *csol = NULL;
+
+ if (!sol)
+ goto error;
+ if (sol->size == 0)
+ isl_die(sol->ctx, isl_error_internal,
+ "no solution found", goto error);
+
+ for (i = 0; i < graph->n; ++i) {
+ struct isl_sched_node *node = &graph->node[i];
+ int pos = node->start;
+ int row = isl_mat_rows(node->sched);
+
+ isl_vec_free(csol);
+ csol = isl_vec_alloc(sol->ctx, node->nvar);
+ if (!csol)
+ goto error;
+
+ isl_map_free(node->sched_map);
+ node->sched_map = NULL;
+ node->sched = isl_mat_add_rows(node->sched, 1);
+ if (!node->sched)
+ goto error;
+ node->sched = isl_mat_set_element(node->sched, row, 0,
+ sol->el[1 + pos]);
+ for (j = 0; j < node->nparam + node->nvar; ++j)
+ isl_int_sub(sol->el[1 + pos + 1 + 2 * j + 1],
+ sol->el[1 + pos + 1 + 2 * j + 1],
+ sol->el[1 + pos + 1 + 2 * j]);
+ for (j = 0; j < node->nparam; ++j)
+ node->sched = isl_mat_set_element(node->sched,
+ row, 1 + j, sol->el[1+pos+1+2*j+1]);
+ for (j = 0; j < node->nvar; ++j)
+ isl_int_set(csol->el[j],
+ sol->el[1+pos+1+2*(node->nparam+j)+1]);
+ if (use_cmap)
+ csol = isl_mat_vec_product(isl_mat_copy(node->cmap),
+ csol);
+ if (!csol)
+ goto error;
+ for (j = 0; j < node->nvar; ++j)
+ node->sched = isl_mat_set_element(node->sched,
+ row, 1 + node->nparam + j, csol->el[j]);
+ node->band[graph->n_total_row] = graph->n_band;
+ }
+ isl_vec_free(sol);
+ isl_vec_free(csol);
+
+ graph->n_row++;
+ graph->n_total_row++;
+
+ return 0;
+error:
+ isl_vec_free(sol);
+ isl_vec_free(csol);
+ return -1;
+}
+
+/* Convert node->sched into a map and return this map.
+ * We simply add equality constraints that express each output variable
+ * as the affine combination of parameters and input variables specified
+ * by the schedule matrix.
+ *
+ * The result is cached in node->sched_map, which needs to be released
+ * whenever node->sched is updated.
+ */
+static __isl_give isl_map *node_extract_schedule(struct isl_sched_node *node)
+{
+ int i, j;
+ isl_dim *dim;
+ isl_basic_map *bmap;
+ isl_constraint *c;
+ int nrow, ncol;
+ isl_int v;
+
+ if (node->sched_map)
+ return isl_map_copy(node->sched_map);
+
+ nrow = isl_mat_rows(node->sched);
+ ncol = isl_mat_cols(node->sched) - 1;
+ dim = isl_dim_from_domain(isl_dim_copy(node->dim));
+ dim = isl_dim_add(dim, isl_dim_out, nrow);
+ bmap = isl_basic_map_universe(isl_dim_copy(dim));
+
+ isl_int_init(v);
+
+ for (i = 0; i < nrow; ++i) {
+ c = isl_equality_alloc(isl_dim_copy(dim));
+ isl_constraint_set_coefficient_si(c, isl_dim_out, i, -1);
+ isl_mat_get_element(node->sched, i, 0, &v);
+ isl_constraint_set_constant(c, v);
+ for (j = 0; j < node->nparam; ++j) {
+ isl_mat_get_element(node->sched, i, 1 + j, &v);
+ isl_constraint_set_coefficient(c, isl_dim_param, j, v);
+ }
+ for (j = 0; j < node->nvar; ++j) {
+ isl_mat_get_element(node->sched,
+ i, 1 + node->nparam + j, &v);
+ isl_constraint_set_coefficient(c, isl_dim_in, j, v);
+ }
+ bmap = isl_basic_map_add_constraint(bmap, c);
+ }
+
+ isl_int_clear(v);
+
+ isl_dim_free(dim);
+
+ node->sched_map = isl_map_from_basic_map(bmap);
+ return isl_map_copy(node->sched_map);
+}
+
+/* Update the given dependence relation based on the current schedule.
+ * That is, intersect the dependence relation with a map expressing
+ * that source and sink are executed within the same iteration of
+ * the current schedule.
+ * This is not the most efficient way, but this shouldn't be a critical
+ * operation.
+ */
+static __isl_give isl_map *specialize(__isl_take isl_map *map,
+ struct isl_sched_node *src, struct isl_sched_node *dst)
+{
+ isl_map *src_sched, *dst_sched, *id;
+
+ src_sched = node_extract_schedule(src);
+ dst_sched = node_extract_schedule(dst);
+ id = isl_map_apply_range(src_sched, isl_map_reverse(dst_sched));
+ return isl_map_intersect(map, id);
+}
+
+/* Update the dependence relations of all edges based on the current schedule.
+ * If a dependence is carried completely by the current schedule, then
+ * it is removed and edge_table is updated accordingly.
+ */
+static int update_edges(isl_ctx *ctx, struct isl_sched_graph *graph)
+{
+ int i;
+ int reset_table = 0;
+
+ for (i = graph->n_edge - 1; i >= 0; --i) {
+ struct isl_sched_edge *edge = &graph->edge[i];
+ edge->map = specialize(edge->map, edge->src, edge->dst);
+ if (!edge->map)
+ return -1;
+
+ if (isl_map_fast_is_empty(edge->map)) {
+ reset_table = 1;
+ isl_map_free(edge->map);
+ if (i != graph->n_edge - 1)
+ graph->edge[i] = graph->edge[graph->n_edge - 1];
+ graph->n_edge--;
+ }
+ }
+
+ if (reset_table) {
+ isl_hash_table_free(ctx, graph->edge_table);
+ graph->edge_table = NULL;
+ return graph_init_edge_table(ctx, graph);
+ }
+
+ return 0;
+}
+
+static void next_band(struct isl_sched_graph *graph)
+{
+ graph->band_start = graph->n_total_row;
+ graph->n_band++;
+}
+
+/* Topologically sort statements mapped to same schedule iteration
+ * and add a row to the schedule corresponding to this order.
+ */
+static int sort_statements(isl_ctx *ctx, struct isl_sched_graph *graph)
+{
+ int i, j;
+
+ if (graph->n <= 1)
+ return 0;
+
+ if (update_edges(ctx, graph) < 0)
+ return -1;
+
+ if (graph->n_edge == 0)
+ return 0;
+
+ if (detect_sccs(graph) < 0)
+ return -1;
+
+ for (i = 0; i < graph->n; ++i) {
+ struct isl_sched_node *node = &graph->node[i];
+ int row = isl_mat_rows(node->sched);
+ int cols = isl_mat_cols(node->sched);
+
+ isl_map_free(node->sched_map);
+ node->sched_map = NULL;
+ node->sched = isl_mat_add_rows(node->sched, 1);
+ if (!node->sched)
+ return -1;
+ node->sched = isl_mat_set_element_si(node->sched, row, 0,
+ node->scc);
+ for (j = 1; j < cols; ++j)
+ node->sched = isl_mat_set_element_si(node->sched,
+ row, j, 0);
+ node->band[graph->n_total_row] = graph->n_band;
+ }
+
+ graph->n_total_row++;
+ next_band(graph);
+
+ return 0;
+}
+
+/* Construct an isl_schedule based on the computed schedule stored
+ * in graph and with parameters specified by dim.
+ */
+static __isl_give isl_schedule *extract_schedule(struct isl_sched_graph *graph,
+ __isl_take isl_dim *dim)
+{
+ int i;
+ isl_ctx *ctx;
+ isl_schedule *sched = NULL;
+
+ if (!dim)
+ return NULL;
+
+ ctx = isl_dim_get_ctx(dim);
+ sched = isl_calloc(ctx, struct isl_schedule,
+ sizeof(struct isl_schedule) +
+ (graph->n - 1) * sizeof(struct isl_schedule_node));
+ if (!sched)
+ goto error;
+
+ sched->n = graph->n;
+ sched->n_band = graph->n_band;
+ sched->n_total_row = graph->n_total_row;
+
+ for (i = 0; i < sched->n; ++i) {
+ int r, b;
+ int *band_end;
+
+ band_end = isl_alloc_array(ctx, int, graph->n_band);
+ if (!band_end)
+ goto error;
+ sched->node[i].sched = node_extract_schedule(&graph->node[i]);
+ sched->node[i].band_end = band_end;
+
+ for (r = b = 0; r < graph->n_total_row; ++r) {
+ if (graph->node[i].band[r] == b)
+ continue;
+ band_end[b++] = r;
+ if (graph->node[i].band[r] == -1)
+ break;
+ }
+ if (r == graph->n_total_row)
+ band_end[b++] = r;
+ sched->node[i].n_band = b;
+ }
+
+ sched->dim = dim;
+
+ return sched;
+error:
+ isl_dim_free(dim);
+ isl_schedule_free(sched);
+ return NULL;
+}
+
+/* Copy nodes that satisfy node_pred from the src dependence graph
+ * to the dst dependence graph.
+ */
+static int copy_nodes(struct isl_sched_graph *dst, struct isl_sched_graph *src,
+ int (*node_pred)(struct isl_sched_node *node, int data), int data)
+{
+ int i;
+
+ dst->n = 0;
+ for (i = 0; i < src->n; ++i) {
+ if (!node_pred(&src->node[i], data))
+ continue;
+ dst->node[dst->n].dim = isl_dim_copy(src->node[i].dim);
+ dst->node[dst->n].nvar = src->node[i].nvar;
+ dst->node[dst->n].nparam = src->node[i].nparam;
+ dst->node[dst->n].sched = isl_mat_copy(src->node[i].sched);
+ dst->node[dst->n].sched_map =
+ isl_map_copy(src->node[i].sched_map);
+ dst->node[dst->n].band = src->node[i].band;
+ dst->n++;
+ }
+
+ return 0;
+}
+
+/* Copy non-empty edges that satisfy edge_pred from the src dependence graph
+ * to the dst dependence graph.
+ */
+static int copy_edges(isl_ctx *ctx, struct isl_sched_graph *dst,
+ struct isl_sched_graph *src,
+ int (*edge_pred)(struct isl_sched_edge *edge, int data), int data)
+{
+ int i;
+
+ dst->n_edge = 0;
+ for (i = 0; i < src->n_edge; ++i) {
+ struct isl_sched_edge *edge = &src->edge[i];
+ isl_map *map;
+
+ if (!edge_pred(edge, data))
+ continue;
+
+ if (isl_map_fast_is_empty(edge->map))
+ continue;
+
+ map = isl_map_copy(edge->map);
+
+ dst->edge[dst->n_edge].src =
+ graph_find_node(ctx, dst, edge->src->dim);
+ dst->edge[dst->n_edge].dst =
+ graph_find_node(ctx, dst, edge->dst->dim);
+ dst->edge[dst->n_edge].map = map;
+ dst->edge[dst->n_edge].validity = edge->validity;
+ dst->edge[dst->n_edge].proximity = edge->proximity;
+ dst->n_edge++;
+ }
+
+ return 0;
+}
+
+/* Given a "src" dependence graph that contains the nodes from "dst"
+ * that satisfy node_pred, copy the schedule computed in "src"
+ * for those nodes back to "dst".
+ */
+static int copy_schedule(struct isl_sched_graph *dst,
+ struct isl_sched_graph *src,
+ int (*node_pred)(struct isl_sched_node *node, int data), int data)
+{
+ int i;
+
+ src->n = 0;
+ for (i = 0; i < dst->n; ++i) {
+ if (!node_pred(&dst->node[i], data))
+ continue;
+ isl_mat_free(dst->node[i].sched);
+ isl_map_free(dst->node[i].sched_map);
+ dst->node[i].sched = isl_mat_copy(src->node[src->n].sched);
+ dst->node[i].sched_map =
+ isl_map_copy(src->node[src->n].sched_map);
+ src->n++;
+ }
+
+ dst->n_total_row = src->n_total_row;
+ dst->n_band = src->n_band;
+
+ return 0;
+}
+
+/* Compute the maximal number of variables over all nodes.
+ * This is the maximal number of linearly independent schedule
+ * rows that we need to compute.
+ * Just in case we end up in a part of the dependence graph
+ * with only lower-dimensional domains, we make sure we will
+ * compute the required amount of extra linearly independent rows.
+ */
+static int compute_maxvar(struct isl_sched_graph *graph)
+{
+ int i;
+
+ graph->maxvar = 0;
+ for (i = 0; i < graph->n; ++i) {
+ struct isl_sched_node *node = &graph->node[i];
+ int nvar;
+
+ if (node_update_cmap(node) < 0)
+ return -1;
+ nvar = node->nvar + graph->n_row - node->rank;
+ if (nvar > graph->maxvar)
+ graph->maxvar = nvar;
+ }
+
+ return 0;
+}
+
+static int compute_schedule(isl_ctx *ctx, struct isl_sched_graph *graph);
+static int compute_schedule_wcc(isl_ctx *ctx, struct isl_sched_graph *graph);
+
+/* Compute a schedule for a subgraph of "graph". In particular, for
+ * the graph composed of nodes that satisfy node_pred and edges that
+ * that satisfy edge_pred. The caller should precompute the number
+ * of nodes and edges that satisfy these predicates and pass them along
+ * as "n" and "n_edge".
+ * If the subgraph is known to consist of a single component, then wcc should
+ * be set and then we call compute_schedule_wcc on the constructed subgraph.
+ * Otherwise, we call compute_schedule, which will check whether the subgraph
+ * is connected.
+ */
+static int compute_sub_schedule(isl_ctx *ctx,
+ struct isl_sched_graph *graph, int n, int n_edge,
+ int (*node_pred)(struct isl_sched_node *node, int data),
+ int (*edge_pred)(struct isl_sched_edge *edge, int data),
+ int data, int wcc)
+{
+ struct isl_sched_graph split = { 0 };
+
+ if (graph_alloc(ctx, &split, n, n_edge) < 0)
+ goto error;
+ if (copy_nodes(&split, graph, node_pred, data) < 0)
+ goto error;
+ if (graph_init_table(ctx, &split) < 0)
+ goto error;
+ if (copy_edges(ctx, &split, graph, edge_pred, data) < 0)
+ goto error;
+ if (graph_init_edge_table(ctx, &split) < 0)
+ goto error;
+ split.n_row = graph->n_row;
+ split.n_total_row = graph->n_total_row;
+ split.n_band = graph->n_band;
+ split.band_start = graph->band_start;
+
+ if (wcc && compute_schedule_wcc(ctx, &split) < 0)
+ goto error;
+ if (!wcc && compute_schedule(ctx, &split) < 0)
+ goto error;
+
+ copy_schedule(graph, &split, node_pred, data);
+
+ graph_free(ctx, &split);
+ return 0;
+error:
+ graph_free(ctx, &split);
+ return -1;
+}
+
+static int node_scc_exactly(struct isl_sched_node *node, int scc)
+{
+ return node->scc == scc;
+}
+
+static int node_scc_at_most(struct isl_sched_node *node, int scc)
+{
+ return node->scc <= scc;
+}
+
+static int node_scc_at_least(struct isl_sched_node *node, int scc)
+{
+ return node->scc >= scc;
+}
+
+static int edge_src_scc_exactly(struct isl_sched_edge *edge, int scc)
+{
+ return edge->src->scc == scc;
+}
+
+static int edge_dst_scc_at_most(struct isl_sched_edge *edge, int scc)
+{
+ return edge->dst->scc <= scc;
+}
+
+static int edge_src_scc_at_least(struct isl_sched_edge *edge, int scc)
+{
+ return edge->src->scc >= scc;
+}
+
+/* Pad the schedules of all nodes with zero rows such that in the end
+ * they all have graph->n_total_row rows.
+ * The extra rows don't belong to any band, so they get assigned band number -1.
+ */
+static int pad_schedule(struct isl_sched_graph *graph)
+{
+ int i, j;
+
+ for (i = 0; i < graph->n; ++i) {
+ struct isl_sched_node *node = &graph->node[i];
+ int row = isl_mat_rows(node->sched);
+ if (graph->n_total_row > row) {
+ isl_map_free(node->sched_map);
+ node->sched_map = NULL;
+ }
+ node->sched = isl_mat_add_zero_rows(node->sched,
+ graph->n_total_row - row);
+ if (!node->sched)
+ return -1;
+ for (j = row; j < graph->n_total_row; ++j)
+ node->band[j] = -1;
+ }
+
+ return 0;
+}
+
+/* Split the current graph into two parts and compute a schedule for each
+ * part individually. In particular, one part consists of all SCCs up
+ * to and including graph->src_scc, while the other part contains the other
+ * SCCS.
+ *
+ * The split is enforced in the schedule by constant rows with two different
+ * values (0 and 1). These constant rows replace the previously computed rows
+ * in the current band.
+ * It would be possible to reuse them as the first rows in the next
+ * band, but recomputing them may result in better rows as we are looking
+ * at a smaller part of the dependence graph.
+ */
+static int compute_split_schedule(isl_ctx *ctx, struct isl_sched_graph *graph)
+{
+ int i, j, n, e1, e2;
+ int n_total_row, orig_total_row;
+ int n_band, orig_band;
+ int drop;
+
+ drop = graph->n_total_row - graph->band_start;
+ graph->n_total_row -= drop;
+ graph->n_row -= drop;
+
+ n = 0;
+ for (i = 0; i < graph->n; ++i) {
+ struct isl_sched_node *node = &graph->node[i];
+ int row = isl_mat_rows(node->sched) - drop;
+ int cols = isl_mat_cols(node->sched);
+ int before = node->scc <= graph->src_scc;
+
+ if (before)
+ n++;
+
+ isl_map_free(node->sched_map);
+ node->sched_map = NULL;
+ node->sched = isl_mat_drop_rows(node->sched,
+ graph->band_start, drop);
+ node->sched = isl_mat_add_rows(node->sched, 1);
+ if (!node->sched)
+ return -1;
+ node->sched = isl_mat_set_element_si(node->sched, row, 0,
+ !before);
+ for (j = 1; j < cols; ++j)
+ node->sched = isl_mat_set_element_si(node->sched,
+ row, j, 0);
+ node->band[graph->n_total_row] = graph->n_band;
+ }
+
+ e1 = e2 = 0;
+ for (i = 0; i < graph->n_edge; ++i) {
+ if (graph->edge[i].dst->scc <= graph->src_scc)
+ e1++;
+ if (graph->edge[i].src->scc > graph->src_scc)
+ e2++;
+ }
+
+ graph->n_total_row++;
+ next_band(graph);
+
+ orig_total_row = graph->n_total_row;
+ orig_band = graph->n_band;
+ if (compute_sub_schedule(ctx, graph, n, e1,
+ &node_scc_at_most, &edge_dst_scc_at_most,
+ graph->src_scc, 0) < 0)
+ return -1;
+ n_total_row = graph->n_total_row;
+ graph->n_total_row = orig_total_row;
+ n_band = graph->n_band;
+ graph->n_band = orig_band;
+ if (compute_sub_schedule(ctx, graph, graph->n - n, e2,
+ &node_scc_at_least, &edge_src_scc_at_least,
+ graph->src_scc + 1, 0) < 0)
+ return -1;
+ if (n_total_row > graph->n_total_row)
+ graph->n_total_row = n_total_row;
+ if (n_band > graph->n_band)
+ graph->n_band = n_band;
+
+ return pad_schedule(graph);
+}
+
+/* Compute the next band of the schedule after updating the dependence
+ * relations based on the the current schedule.
+ */
+static int compute_next_band(isl_ctx *ctx, struct isl_sched_graph *graph)
+{
+ if (update_edges(ctx, graph) < 0)
+ return -1;
+ next_band(graph);
+
+ return compute_schedule(ctx, graph);
+}
+
+/* Add constraints to graph->lp that force the dependence of edge i
+ * to be respected and attempt to carry it, where edge i is one from
+ * a node j to itself.
+ * That is, add constraints that enforce
+ *
+ * (c_j_0 + c_j_n n + c_j_x y) - (c_j_0 + c_j_n n + c_j_x x)
+ * = c_j_x (y - x) >= e_i
+ *
+ * for each (x,y) in R.
+ * We obtain general constraints on coefficients (c_0, c_n, c_x)
+ * of valid constraints for (y - x) and then plug in (-e_i, 0, c_j_x),
+ * with each coefficient in c_j_x represented as a pair of non-negative
+ * coefficients.
+ */
+static int add_intra_constraints(struct isl_sched_graph *graph, int i)
+{
+ unsigned total;
+ struct isl_sched_edge *edge= &graph->edge[i];
+ isl_map *map = isl_map_copy(edge->map);
+ isl_ctx *ctx = isl_map_get_ctx(map);
+ isl_dim *dim;
+ isl_dim_map *dim_map;
+ isl_basic_set *coef;
+ struct isl_sched_node *node = edge->src;
+
+ coef = intra_coefficients(graph, map);
+
+ dim = isl_dim_domain(isl_dim_unwrap(isl_basic_set_get_dim(coef)));
+
+ total = isl_basic_set_total_dim(graph->lp);
+ dim_map = isl_dim_map_alloc(ctx, total);
+ isl_dim_map_range(dim_map, 3 + i, 0, 0, 0, 1, -1);
+ isl_dim_map_range(dim_map, node->start + 2 * node->nparam + 1, 2,
+ isl_dim_size(dim, isl_dim_set), 1,
+ node->nvar, -1);
+ isl_dim_map_range(dim_map, node->start + 2 * node->nparam + 2, 2,
+ isl_dim_size(dim, isl_dim_set), 1,
+ node->nvar, 1);
+ graph->lp = isl_basic_set_extend_constraints(graph->lp,
+ coef->n_eq, coef->n_ineq);
+ graph->lp = isl_basic_set_add_constraints_dim_map(graph->lp,
+ coef, dim_map);
+ isl_dim_free(dim);
+
+ return 0;
+}
+
+/* Add constraints to graph->lp that force the dependence of edge i
+ * to be respected and attempt to carry it, where edge i is one from
+ * node j to node k.
+ * That is, add constraints that enforce
+ *
+ * (c_k_0 + c_k_n n + c_k_x y) - (c_j_0 + c_j_n n + c_j_x x) >= e_i
+ *
+ * for each (x,y) in R.
+ * We obtain general constraints on coefficients (c_0, c_n, c_x)
+ * of valid constraints for R and then plug in
+ * (-e_i + c_k_0 - c_j_0, c_k_n - c_j_n, c_k_x - c_j_x)
+ * with each coefficient (except e_i, c_k_0 and c_j_0)
+ * represented as a pair of non-negative coefficients.
+ */
+static int add_inter_constraints(struct isl_sched_graph *graph, int i)
+{
+ unsigned total;
+ struct isl_sched_edge *edge= &graph->edge[i];
+ isl_map *map = isl_map_copy(edge->map);
+ isl_ctx *ctx = isl_map_get_ctx(map);
+ isl_dim *dim;
+ isl_dim_map *dim_map;
+ isl_basic_set *coef;
+ struct isl_sched_node *src = edge->src;
+ struct isl_sched_node *dst = edge->dst;
+
+ coef = inter_coefficients(graph, map);
+
+ dim = isl_dim_domain(isl_dim_unwrap(isl_basic_set_get_dim(coef)));
+
+ total = isl_basic_set_total_dim(graph->lp);
+ dim_map = isl_dim_map_alloc(ctx, total);
+
+ isl_dim_map_range(dim_map, 3 + i, 0, 0, 0, 1, -1);
+
+ isl_dim_map_range(dim_map, dst->start, 0, 0, 0, 1, 1);
+ isl_dim_map_range(dim_map, dst->start + 1, 2, 1, 1, dst->nparam, -1);
+ isl_dim_map_range(dim_map, dst->start + 2, 2, 1, 1, dst->nparam, 1);
+ isl_dim_map_range(dim_map, dst->start + 2 * dst->nparam + 1, 2,
+ isl_dim_size(dim, isl_dim_set) + src->nvar, 1,
+ dst->nvar, -1);
+ isl_dim_map_range(dim_map, dst->start + 2 * dst->nparam + 2, 2,
+ isl_dim_size(dim, isl_dim_set) + src->nvar, 1,
+ dst->nvar, 1);
+
+ isl_dim_map_range(dim_map, src->start, 0, 0, 0, 1, -1);
+ isl_dim_map_range(dim_map, src->start + 1, 2, 1, 1, src->nparam, 1);
+ isl_dim_map_range(dim_map, src->start + 2, 2, 1, 1, src->nparam, -1);
+ isl_dim_map_range(dim_map, src->start + 2 * src->nparam + 1, 2,
+ isl_dim_size(dim, isl_dim_set), 1,
+ src->nvar, 1);
+ isl_dim_map_range(dim_map, src->start + 2 * src->nparam + 2, 2,
+ isl_dim_size(dim, isl_dim_set), 1,
+ src->nvar, -1);
+
+ graph->lp = isl_basic_set_extend_constraints(graph->lp,
+ coef->n_eq, coef->n_ineq);
+ graph->lp = isl_basic_set_add_constraints_dim_map(graph->lp,
+ coef, dim_map);
+ isl_dim_free(dim);
+
+ return 0;
+}
+
+/* Add constraints to graph->lp that force all dependence
+ * to be respected and attempt to carry it.
+ */
+static int add_all_constraints(struct isl_sched_graph *graph)
+{
+ int i;
+
+ for (i = 0; i < graph->n_edge; ++i) {
+ struct isl_sched_edge *edge= &graph->edge[i];
+ if (edge->src == edge->dst &&
+ add_intra_constraints(graph, i) < 0)
+ return -1;
+ if (edge->src != edge->dst &&
+ add_inter_constraints(graph, i) < 0)
+ return -1;
+ }
+
+ return 0;
+}
+
+/* Construct an LP problem for finding schedule coefficients
+ * such that the schedule carries as many dependences as possible.
+ * In particular, for each dependence i, we bound the dependence distance
+ * from below by e_i, with 0 <= e_i <= 1 and then maximize the sum
+ * of all e_i's. Dependence with e_i = 0 in the solution are simply
+ * respected, while those with e_i > 0 (in practice e_i = 1) are carried.
+ *
+ * All variables of the LP are non-negative. The actual coefficients
+ * may be negative, so each coefficient is represented as the difference
+ * of two non-negative variables. The negative part always appears
+ * immediately before the positive part.
+ * Other than that, the variables have the following order
+ *
+ * - sum of (1 - e_i) over all edges
+ * - sum of positive and negative parts of all c_n coefficients
+ * (unconstrained when computing non-parametric schedules)
+ * - sum of positive and negative parts of all c_x coefficients
+ * - for each edge
+ * - e_i
+ * - for each node
+ * - c_i_0
+ * - positive and negative parts of c_i_n (if parametric)
+ * - positive and negative parts of c_i_x
+ *
+ * The constraints are those from the edges plus three equalities
+ * to express the sums and n_edge inequalities to express e_i <= 1.
+ */
+static int setup_carry_lp(isl_ctx *ctx, struct isl_sched_graph *graph)
+{
+ int i, j;
+ int k;
+ isl_dim *dim;
+ unsigned total;
+ int n_eq, n_ineq;
+
+ total = 3 + graph->n_edge;
+ for (i = 0; i < graph->n; ++i) {
+ struct isl_sched_node *node = &graph->node[graph->sorted[i]];
+ node->start = total;
+ total += 1 + 2 * (node->nparam + node->nvar);
+ }
+
+ if (count_constraints(graph, &n_eq, &n_ineq, 1) < 0)
+ return -1;
+
+ dim = isl_dim_set_alloc(ctx, 0, total);
+ isl_basic_set_free(graph->lp);
+ n_eq += 3;
+ n_ineq += graph->n_edge;
+ graph->lp = isl_basic_set_alloc_dim(dim, 0, n_eq, n_ineq);
+ graph->lp = isl_basic_set_set_rational(graph->lp);
+
+ k = isl_basic_set_alloc_equality(graph->lp);
+ if (k < 0)
+ return -1;
+ isl_seq_clr(graph->lp->eq[k], 1 + total);
+ isl_int_set_si(graph->lp->eq[k][0], -graph->n_edge);
+ isl_int_set_si(graph->lp->eq[k][1], 1);
+ for (i = 0; i < graph->n_edge; ++i)
+ isl_int_set_si(graph->lp->eq[k][4 + i], 1);
+
+ k = isl_basic_set_alloc_equality(graph->lp);
+ if (k < 0)
+ return -1;
+ isl_seq_clr(graph->lp->eq[k], 1 + total);
+ isl_int_set_si(graph->lp->eq[k][2], -1);
+ for (i = 0; i < graph->n; ++i) {
+ int pos = 1 + graph->node[i].start + 1;
+
+ for (j = 0; j < 2 * graph->node[i].nparam; ++j)
+ isl_int_set_si(graph->lp->eq[k][pos + j], 1);
+ }
+
+ k = isl_basic_set_alloc_equality(graph->lp);
+ if (k < 0)
+ return -1;
+ isl_seq_clr(graph->lp->eq[k], 1 + total);
+ isl_int_set_si(graph->lp->eq[k][3], -1);
+ for (i = 0; i < graph->n; ++i) {
+ struct isl_sched_node *node = &graph->node[i];
+ int pos = 1 + node->start + 1 + 2 * node->nparam;
+
+ for (j = 0; j < 2 * node->nvar; ++j)
+ isl_int_set_si(graph->lp->eq[k][pos + j], 1);
+ }
+
+ for (i = 0; i < graph->n_edge; ++i) {
+ k = isl_basic_set_alloc_inequality(graph->lp);
+ if (k < 0)
+ return -1;
+ isl_seq_clr(graph->lp->ineq[k], 1 + total);
+ isl_int_set_si(graph->lp->ineq[k][4 + i], -1);
+ isl_int_set_si(graph->lp->ineq[k][0], 1);
+ }
+
+ if (add_all_constraints(graph) < 0)
+ return -1;
+
+ return 0;
+}
+
+/* Construct a schedule row for each node such that as many dependences
+ * as possible are carried and then continue with the next band.
+ */
+static int carry_dependences(isl_ctx *ctx, struct isl_sched_graph *graph)
+{
+ isl_vec *sol;
+ isl_basic_set *lp;
+
+ if (setup_carry_lp(ctx, graph) < 0)
+ return -1;
+
+ lp = isl_basic_set_copy(graph->lp);
+ sol = isl_tab_basic_set_non_neg_lexmin(lp);
+ if (!sol)
+ return -1;
+
+ if (sol->size == 0) {
+ isl_vec_free(sol);
+ isl_die(ctx, isl_error_internal,
+ "error in schedule construction", return -1);
+ }
+
+ if (isl_int_cmp_si(sol->el[1], graph->n_edge) >= 0) {
+ isl_vec_free(sol);
+ isl_die(ctx, isl_error_unknown,
+ "unable to carry dependences", return -1);
+ }
+
+ if (update_schedule(graph, sol, 0) < 0)
+ return -1;
+
+ return compute_next_band(ctx, graph);
+}
+
+/* Compute a schedule for a connected dependence graph.
+ * We try to find a sequence of as many schedule rows as possible that result
+ * in non-negative dependence distances (independent of the previous rows
+ * in the sequence, i.e., such that the sequence is tilable).
+ * If we can't find any more rows we either
+ * - split between SCCs and start over (assuming we found an interesting
+ * pair of SCCs between which to split)
+ * - continue with the next band (assuming the current band has at least
+ * one row)
+ * - try to carry as many dependences as possible and continue with the next
+ * band
+ *
+ * If we manage to complete the schedule, we finish off by topologically
+ * sorting the statements based on the remaining dependences.
+ */
+static int compute_schedule_wcc(isl_ctx *ctx, struct isl_sched_graph *graph)
+{
+ if (detect_sccs(graph) < 0)
+ return -1;
+ sort_sccs(graph);
+
+ if (compute_maxvar(graph) < 0)
+ return -1;
+
+ while (graph->n_row < graph->maxvar) {
+ isl_vec *sol;
+
+ graph->src_scc = -1;
+ graph->dst_scc = -1;
+
+ if (setup_lp(ctx, graph) < 0)
+ return -1;
+ sol = solve_lp(graph);
+ if (!sol)
+ return -1;
+ if (sol->size == 0) {
+ isl_vec_free(sol);
+ if (graph->src_scc >= 0)
+ return compute_split_schedule(ctx, graph);
+ if (graph->n_total_row > graph->band_start)
+ return compute_next_band(ctx, graph);
+ return carry_dependences(ctx, graph);
+ }
+ if (update_schedule(graph, sol, 1) < 0)
+ return -1;
+ }
+
+ if (graph->n_total_row > graph->band_start)
+ next_band(graph);
+ return sort_statements(ctx, graph);
+}
+
+/* Compute a schedule for each component (identified by node->scc)
+ * of the dependence graph separately and then combine the results.
+ */
+static int compute_component_schedule(isl_ctx *ctx,
+ struct isl_sched_graph *graph)
+{
+ int wcc, i;
+ int n, n_edge;
+ int n_total_row, orig_total_row;
+ int n_band, orig_band;
+
+ n_total_row = 0;
+ orig_total_row = graph->n_total_row;
+ n_band = 0;
+ orig_band = graph->n_band;
+ for (wcc = 0; wcc < graph->scc; ++wcc) {
+ n = 0;
+ for (i = 0; i < graph->n; ++i)
+ if (graph->node[i].scc == wcc)
+ n++;
+ n_edge = 0;
+ for (i = 0; i < graph->n_edge; ++i)
+ if (graph->edge[i].src->scc == wcc)
+ n_edge++;
+
+ if (compute_sub_schedule(ctx, graph, n, n_edge,
+ &node_scc_exactly,
+ &edge_src_scc_exactly, wcc, 1) < 0)
+ return -1;
+ if (graph->n_total_row > n_total_row)
+ n_total_row = graph->n_total_row;
+ graph->n_total_row = orig_total_row;
+ if (graph->n_band > n_band)
+ n_band = graph->n_band;
+ graph->n_band = orig_band;
+ }
+
+ graph->n_total_row = n_total_row;
+ graph->n_band = n_band;
+
+ return pad_schedule(graph);
+}
+
+/* Compute a schedule for the given dependence graph.
+ * We first check if the graph is connected (through validity dependences)
+ * and if so compute a schedule for each component separately.
+ */
+static int compute_schedule(isl_ctx *ctx, struct isl_sched_graph *graph)
+{
+ if (detect_wccs(graph) < 0)
+ return -1;
+
+ if (graph->scc > 1)
+ return compute_component_schedule(ctx, graph);
+
+ return compute_schedule_wcc(ctx, graph);
+}
+
+/* Compute a schedule for the given union of domains that respects
+ * all the validity dependences and tries to minimize the dependence
+ * distances over the proximity dependences.
+ */
+__isl_give isl_schedule *isl_union_set_compute_schedule(
+ __isl_take isl_union_set *domain,
+ __isl_take isl_union_map *validity,
+ __isl_take isl_union_map *proximity)
+{
+ isl_ctx *ctx = isl_union_set_get_ctx(domain);
+ isl_dim *dim;
+ struct isl_sched_graph graph = { 0 };
+ isl_schedule *sched;
+
+ domain = isl_union_set_align_params(domain,
+ isl_union_map_get_dim(validity));
+ domain = isl_union_set_align_params(domain,
+ isl_union_map_get_dim(proximity));
+ dim = isl_union_set_get_dim(domain);
+ validity = isl_union_map_align_params(validity, isl_dim_copy(dim));
+ proximity = isl_union_map_align_params(proximity, dim);
+
+ if (!domain)
+ goto error;
+
+ graph.n = isl_union_set_n_set(domain);
+ if (graph.n == 0)
+ goto empty;
+ if (graph_alloc(ctx, &graph, graph.n,
+ isl_union_map_n_map(validity) + isl_union_map_n_map(proximity)) < 0)
+ goto error;
+ graph.root = 1;
+ graph.n = 0;
+ if (isl_union_set_foreach_set(domain, &extract_node, &graph) < 0)
+ goto error;
+ if (graph_init_table(ctx, &graph) < 0)
+ goto error;
+ graph.n_edge = 0;
+ if (isl_union_map_foreach_map(validity, &extract_edge, &graph) < 0)
+ goto error;
+ if (graph_init_edge_table(ctx, &graph) < 0)
+ goto error;
+ if (isl_union_map_foreach_map(proximity, &extract_edge, &graph) < 0)
+ goto error;
+
+ if (compute_schedule(ctx, &graph) < 0)
+ goto error;
+
+empty:
+ sched = extract_schedule(&graph, isl_union_set_get_dim(domain));
+
+ graph_free(ctx, &graph);
+ isl_union_set_free(domain);
+ isl_union_map_free(validity);
+ isl_union_map_free(proximity);
+
+ return sched;
+error:
+ graph_free(ctx, &graph);
+ isl_union_set_free(domain);
+ isl_union_map_free(validity);
+ isl_union_map_free(proximity);
+ return NULL;
+}
+
+void *isl_schedule_free(__isl_take isl_schedule *sched)
+{
+ int i;
+ if (!sched)
+ return NULL;
+ for (i = 0; i < sched->n; ++i) {
+ isl_map_free(sched->node[i].sched);
+ free(sched->node[i].band_end);
+ }
+ isl_dim_free(sched->dim);
+ free(sched);
+ return NULL;
+}
+
+__isl_give isl_union_map *isl_schedule_get_map(__isl_keep isl_schedule *sched)
+{
+ int i;
+ isl_union_map *umap;
+
+ if (!sched)
+ return NULL;
+
+ umap = isl_union_map_empty(isl_dim_copy(sched->dim));
+ for (i = 0; i < sched->n; ++i)
+ umap = isl_union_map_add_map(umap,
+ isl_map_copy(sched->node[i].sched));
+
+ return umap;
+}
+
+int isl_schedule_n_band(__isl_keep isl_schedule *sched)
+{
+ return sched ? sched->n_band : 0;
+}
+
+/* Construct a mapping that maps each domain to the band in its schedule
+ * with the specified band index. Note that bands with the same index
+ * but for different domains do not need to be related.
+ */
+__isl_give isl_union_map *isl_schedule_get_band(__isl_keep isl_schedule *sched,
+ unsigned band)
+{
+ int i;
+ isl_union_map *umap;
+
+ if (!sched)
+ return NULL;
+
+ umap = isl_union_map_empty(isl_dim_copy(sched->dim));
+ for (i = 0; i < sched->n; ++i) {
+ int start, end;
+ isl_map *map;
+
+ if (band >= sched->node[i].n_band)
+ continue;
+
+ start = band > 0 ? sched->node[i].band_end[band - 1] : 0;
+ end = sched->node[i].band_end[band];
+
+ map = isl_map_copy(sched->node[i].sched);
+
+ map = isl_map_project_out(map, isl_dim_out, end,
+ sched->n_total_row - end);
+ map = isl_map_project_out(map, isl_dim_out, 0, start);
+
+ umap = isl_union_map_add_map(umap, map);
+ }
+
+ return umap;
+}
#include <isl/polynomial.h>
#include <isl/union_map.h>
#include <isl_factorization.h>
+#include <isl/schedule.h>
static char *srcdir;
isl_factorizer_free(f);
}
+static int check_injective(__isl_take isl_map *map, void *user)
+{
+ int *injective = user;
+
+ *injective = isl_map_is_injective(map);
+ isl_map_free(map);
+
+ if (*injective < 0 || !*injective)
+ return -1;
+
+ return 0;
+}
+
+int test_one_schedule(isl_ctx *ctx, const char *d, const char *w,
+ const char *r, const char *s, int tilable, int parallel)
+{
+ int i;
+ isl_union_set *D;
+ isl_union_map *W, *R, *S;
+ isl_union_map *empty;
+ isl_union_map *dep_raw, *dep_war, *dep_waw, *dep;
+ isl_union_map *validity, *proximity;
+ isl_union_map *schedule;
+ isl_union_map *test;
+ isl_union_set *delta;
+ isl_union_set *domain;
+ isl_set *delta_set;
+ isl_set *slice;
+ isl_set *origin;
+ isl_schedule *sched;
+ int is_nonneg, is_parallel, is_tilable, is_injection, is_complete;
+
+ D = isl_union_set_read_from_str(ctx, d);
+ W = isl_union_map_read_from_str(ctx, w);
+ R = isl_union_map_read_from_str(ctx, r);
+ S = isl_union_map_read_from_str(ctx, s);
+
+ W = isl_union_map_intersect_domain(W, isl_union_set_copy(D));
+ R = isl_union_map_intersect_domain(R, isl_union_set_copy(D));
+
+ empty = isl_union_map_empty(isl_union_map_get_dim(S));
+ isl_union_map_compute_flow(isl_union_map_copy(R),
+ isl_union_map_copy(W), empty,
+ isl_union_map_copy(S),
+ &dep_raw, NULL, NULL, NULL);
+ isl_union_map_compute_flow(isl_union_map_copy(W),
+ isl_union_map_copy(W),
+ isl_union_map_copy(R),
+ isl_union_map_copy(S),
+ &dep_waw, &dep_war, NULL, NULL);
+
+ dep = isl_union_map_union(dep_waw, dep_war);
+ dep = isl_union_map_union(dep, dep_raw);
+ validity = isl_union_map_copy(dep);
+ proximity = isl_union_map_copy(dep);
+
+ sched = isl_union_set_compute_schedule(isl_union_set_copy(D),
+ validity, proximity);
+ schedule = isl_schedule_get_map(sched);
+ isl_schedule_free(sched);
+ isl_union_map_free(W);
+ isl_union_map_free(R);
+ isl_union_map_free(S);
+
+ is_injection = 1;
+ isl_union_map_foreach_map(schedule, &check_injective, &is_injection);
+
+ domain = isl_union_map_domain(isl_union_map_copy(schedule));
+ is_complete = isl_union_set_is_subset(D, domain);
+ isl_union_set_free(D);
+ isl_union_set_free(domain);
+
+ test = isl_union_map_reverse(isl_union_map_copy(schedule));
+ test = isl_union_map_apply_range(test, dep);
+ test = isl_union_map_apply_range(test, schedule);
+
+ delta = isl_union_map_deltas(test);
+ if (isl_union_set_n_set(delta) == 0) {
+ is_tilable = 1;
+ is_parallel = 1;
+ is_nonneg = 1;
+ } else {
+ delta_set = isl_union_set_copy_set(delta);
+
+ slice = isl_set_universe(isl_set_get_dim(delta_set));
+ for (i = 0; i < tilable; ++i)
+ slice = isl_set_lower_bound_si(slice, isl_dim_set, i, 0);
+ is_tilable = isl_set_is_subset(delta_set, slice);
+ isl_set_free(slice);
+
+ slice = isl_set_universe(isl_set_get_dim(delta_set));
+ for (i = 0; i < parallel; ++i)
+ slice = isl_set_fix_si(slice, isl_dim_set, i, 0);
+ is_parallel = isl_set_is_subset(delta_set, slice);
+ isl_set_free(slice);
+
+ origin = isl_set_universe(isl_set_get_dim(delta_set));
+ for (i = 0; i < isl_set_dim(origin, isl_dim_set); ++i)
+ origin = isl_set_fix_si(origin, isl_dim_set, i, 0);
+
+ delta_set = isl_set_union(delta_set, isl_set_copy(origin));
+ delta_set = isl_set_lexmin(delta_set);
+
+ is_nonneg = isl_set_is_equal(delta_set, origin);
+
+ isl_set_free(origin);
+ isl_set_free(delta_set);
+ }
+ isl_union_set_free(delta);
+
+ if (is_nonneg < 0 || is_parallel < 0 || is_tilable < 0 ||
+ is_injection < 0 || is_complete < 0)
+ return -1;
+ if (!is_complete)
+ isl_die(ctx, isl_error_unknown,
+ "generated schedule incomplete", return -1);
+ if (!is_injection)
+ isl_die(ctx, isl_error_unknown,
+ "generated schedule not injective on each statement",
+ return -1);
+ if (!is_nonneg)
+ isl_die(ctx, isl_error_unknown,
+ "negative dependences in generated schedule",
+ return -1);
+ if (!is_tilable)
+ isl_die(ctx, isl_error_unknown,
+ "generated schedule not as tilable as expected",
+ return -1);
+ if (!is_parallel)
+ isl_die(ctx, isl_error_unknown,
+ "generated schedule not as parallel as expected",
+ return -1);
+
+ return 0;
+}
+
+int test_special_schedule(isl_ctx *ctx)
+{
+ const char *str;
+ isl_union_set *dom;
+ isl_union_map *empty;
+ isl_union_map *dep;
+ isl_union_map *sched1, *sched2;
+ isl_schedule *schedule;
+ int equal;
+
+ str = "{ S[i,j] : 0 <= i <= 10 }";
+ dom = isl_union_set_read_from_str(ctx, str);
+ str = "{ S[i,j] -> S[i+1,j] : 0 <= i,j <= 10 }";
+ dep = isl_union_map_read_from_str(ctx, str);
+ empty = isl_union_map_read_from_str(ctx, "{}");
+ schedule = isl_union_set_compute_schedule(dom, empty, dep);
+ sched1 = isl_schedule_get_map(schedule);
+ isl_schedule_free(schedule);
+
+ str = "{ S[i, j] -> [j, i] }";
+ sched2 = isl_union_map_read_from_str(ctx, str);
+
+ equal = isl_union_map_is_equal(sched1, sched2);
+ isl_union_map_free(sched1);
+ isl_union_map_free(sched2);
+
+ if (equal < 0)
+ return -1;
+ if (!equal)
+ isl_die(ctx, isl_error_unknown, "unexpected schedule",
+ return -1);
+
+ return 0;
+}
+
+int test_schedule(isl_ctx *ctx)
+{
+ const char *D, *W, *R, *S;
+
+ /* Jacobi */
+ D = "[T,N] -> { S1[t,i] : 1 <= t <= T and 2 <= i <= N - 1 }";
+ W = "{ S1[t,i] -> a[t,i] }";
+ R = "{ S1[t,i] -> a[t-1,i]; S1[t,i] -> a[t-1,i-1]; "
+ "S1[t,i] -> a[t-1,i+1] }";
+ S = "{ S1[t,i] -> [t,i] }";
+ if (test_one_schedule(ctx, D, W, R, S, 2, 0) < 0)
+ return -1;
+
+ /* Fig. 5 of CC2008 */
+ D = "[N] -> { S_0[i, j] : i >= 0 and i <= -1 + N and j >= 2 and "
+ "j <= -1 + N }";
+ W = "[N] -> { S_0[i, j] -> a[i, j] : i >= 0 and i <= -1 + N and "
+ "j >= 2 and j <= -1 + N }";
+ R = "[N] -> { S_0[i, j] -> a[j, i] : i >= 0 and i <= -1 + N and "
+ "j >= 2 and j <= -1 + N; "
+ "S_0[i, j] -> a[i, -1 + j] : i >= 0 and i <= -1 + N and "
+ "j >= 2 and j <= -1 + N }";
+ S = "[N] -> { S_0[i, j] -> [0, i, 0, j, 0] }";
+ if (test_one_schedule(ctx, D, W, R, S, 2, 0) < 0)
+ return -1;
+
+ D = "{ S1[i] : 0 <= i <= 10; S2[i] : 0 <= i <= 9 }";
+ W = "{ S1[i] -> a[i] }";
+ R = "{ S2[i] -> a[i+1] }";
+ S = "{ S1[i] -> [0,i]; S2[i] -> [1,i] }";
+ if (test_one_schedule(ctx, D, W, R, S, 1, 1) < 0)
+ return -1;
+
+ D = "{ S1[i] : 0 <= i < 10; S2[i] : 0 <= i < 10 }";
+ W = "{ S1[i] -> a[i] }";
+ R = "{ S2[i] -> a[9-i] }";
+ S = "{ S1[i] -> [0,i]; S2[i] -> [1,i] }";
+ if (test_one_schedule(ctx, D, W, R, S, 1, 1) < 0)
+ return -1;
+
+ D = "[N] -> { S1[i] : 0 <= i < N; S2[i] : 0 <= i < N }";
+ W = "{ S1[i] -> a[i] }";
+ R = "[N] -> { S2[i] -> a[N-1-i] }";
+ S = "{ S1[i] -> [0,i]; S2[i] -> [1,i] }";
+ if (test_one_schedule(ctx, D, W, R, S, 1, 1) < 0)
+ return -1;
+
+ D = "{ S1[i] : 0 < i < 10; S2[i] : 0 <= i < 10 }";
+ W = "{ S1[i] -> a[i]; S2[i] -> b[i] }";
+ R = "{ S2[i] -> a[i]; S1[i] -> b[i-1] }";
+ S = "{ S1[i] -> [i,0]; S2[i] -> [i,1] }";
+ if (test_one_schedule(ctx, D, W, R, S, 0, 0) < 0)
+ return -1;
+
+ D = "[N] -> { S1[i] : 1 <= i <= N; S2[i,j] : 1 <= i,j <= N }";
+ W = "{ S1[i] -> a[0,i]; S2[i,j] -> a[i,j] }";
+ R = "{ S2[i,j] -> a[i-1,j] }";
+ S = "{ S1[i] -> [0,i,0]; S2[i,j] -> [1,i,j] }";
+ if (test_one_schedule(ctx, D, W, R, S, 2, 1) < 0)
+ return -1;
+
+ D = "[N] -> { S1[i] : 1 <= i <= N; S2[i,j] : 1 <= i,j <= N }";
+ W = "{ S1[i] -> a[i,0]; S2[i,j] -> a[i,j] }";
+ R = "{ S2[i,j] -> a[i,j-1] }";
+ S = "{ S1[i] -> [0,i,0]; S2[i,j] -> [1,i,j] }";
+ if (test_one_schedule(ctx, D, W, R, S, 2, 1) < 0)
+ return -1;
+
+ D = "[N] -> { S_0[]; S_1[i] : i >= 0 and i <= -1 + N; S_2[] }";
+ W = "[N] -> { S_0[] -> a[0]; S_2[] -> b[0]; "
+ "S_1[i] -> a[1 + i] : i >= 0 and i <= -1 + N }";
+ R = "[N] -> { S_2[] -> a[N]; S_1[i] -> a[i] : i >= 0 and i <= -1 + N }";
+ S = "[N] -> { S_1[i] -> [1, i, 0]; S_2[] -> [2, 0, 1]; "
+ "S_0[] -> [0, 0, 0] }";
+ if (test_one_schedule(ctx, D, W, R, S, 1, 0) < 0)
+ return -1;
+ ctx->opt->schedule_parametric = 0;
+ if (test_one_schedule(ctx, D, W, R, S, 0, 0) < 0)
+ return -1;
+ ctx->opt->schedule_parametric = 1;
+
+ D = "[N] -> { S1[i] : 1 <= i <= N; S2[i] : 1 <= i <= N; "
+ "S3[i,j] : 1 <= i,j <= N; S4[i] : 1 <= i <= N }";
+ W = "{ S1[i] -> a[i,0]; S2[i] -> a[0,i]; S3[i,j] -> a[i,j] }";
+ R = "[N] -> { S3[i,j] -> a[i-1,j]; S3[i,j] -> a[i,j-1]; "
+ "S4[i] -> a[i,N] }";
+ S = "{ S1[i] -> [0,i,0]; S2[i] -> [1,i,0]; S3[i,j] -> [2,i,j]; "
+ "S4[i] -> [4,i,0] }";
+ if (test_one_schedule(ctx, D, W, R, S, 2, 0) < 0)
+ return -1;
+
+ D = "[N] -> { S_0[i, j] : i >= 1 and i <= N and j >= 1 and j <= N }";
+ W = "[N] -> { S_0[i, j] -> s[0] : i >= 1 and i <= N and j >= 1 and "
+ "j <= N }";
+ R = "[N] -> { S_0[i, j] -> s[0] : i >= 1 and i <= N and j >= 1 and "
+ "j <= N; "
+ "S_0[i, j] -> a[i, j] : i >= 1 and i <= N and j >= 1 and "
+ "j <= N }";
+ S = "[N] -> { S_0[i, j] -> [0, i, 0, j, 0] }";
+ if (test_one_schedule(ctx, D, W, R, S, 0, 0) < 0)
+ return -1;
+
+ D = "[N] -> { S_0[t] : t >= 0 and t <= -1 + N; "
+ " S_2[t] : t >= 0 and t <= -1 + N; "
+ " S_1[t, i] : t >= 0 and t <= -1 + N and i >= 0 and "
+ "i <= -1 + N }";
+ W = "[N] -> { S_0[t] -> a[t, 0] : t >= 0 and t <= -1 + N; "
+ " S_2[t] -> b[t] : t >= 0 and t <= -1 + N; "
+ " S_1[t, i] -> a[t, 1 + i] : t >= 0 and t <= -1 + N and "
+ "i >= 0 and i <= -1 + N }";
+ R = "[N] -> { S_1[t, i] -> a[t, i] : t >= 0 and t <= -1 + N and "
+ "i >= 0 and i <= -1 + N; "
+ " S_2[t] -> a[t, N] : t >= 0 and t <= -1 + N }";
+ S = "[N] -> { S_2[t] -> [0, t, 2]; S_1[t, i] -> [0, t, 1, i, 0]; "
+ " S_0[t] -> [0, t, 0] }";
+
+ if (test_one_schedule(ctx, D, W, R, S, 2, 1) < 0)
+ return -1;
+ ctx->opt->schedule_parametric = 0;
+ if (test_one_schedule(ctx, D, W, R, S, 0, 0) < 0)
+ return -1;
+ ctx->opt->schedule_parametric = 1;
+
+ D = "[N] -> { S1[i,j] : 0 <= i,j < N; S2[i,j] : 0 <= i,j < N }";
+ S = "{ S1[i,j] -> [0,i,j]; S2[i,j] -> [1,i,j] }";
+ if (test_one_schedule(ctx, D, "{}", "{}", S, 2, 2) < 0)
+ return -1;
+
+ D = "[M, N] -> { S_1[i] : i >= 0 and i <= -1 + M; "
+ "S_0[i, j] : i >= 0 and i <= -1 + M and j >= 0 and j <= -1 + N }";
+ W = "[M, N] -> { S_0[i, j] -> a[j] : i >= 0 and i <= -1 + M and "
+ "j >= 0 and j <= -1 + N; "
+ "S_1[i] -> b[0] : i >= 0 and i <= -1 + M }";
+ R = "[M, N] -> { S_0[i, j] -> a[0] : i >= 0 and i <= -1 + M and "
+ "j >= 0 and j <= -1 + N; "
+ "S_1[i] -> b[0] : i >= 0 and i <= -1 + M }";
+ S = "[M, N] -> { S_1[i] -> [1, i, 0]; S_0[i, j] -> [0, i, 0, j, 0] }";
+ if (test_one_schedule(ctx, D, W, R, S, 0, 0) < 0)
+ return -1;
+
+ D = "{ S_0[i] : i >= 0 }";
+ W = "{ S_0[i] -> a[i] : i >= 0 }";
+ R = "{ S_0[i] -> a[0] : i >= 0 }";
+ S = "{ S_0[i] -> [0, i, 0] }";
+ if (test_one_schedule(ctx, D, W, R, S, 0, 0) < 0)
+ return -1;
+
+ D = "{ S_0[i] : i >= 0; S_1[i] : i >= 0 }";
+ W = "{ S_0[i] -> a[i] : i >= 0; S_1[i] -> b[i] : i >= 0 }";
+ R = "{ S_0[i] -> b[0] : i >= 0; S_1[i] -> a[i] : i >= 0 }";
+ S = "{ S_1[i] -> [0, i, 1]; S_0[i] -> [0, i, 0] }";
+ if (test_one_schedule(ctx, D, W, R, S, 0, 0) < 0)
+ return -1;
+
+ return test_special_schedule(ctx);
+}
+
int main()
{
struct isl_ctx *ctx;
assert(srcdir);
ctx = isl_ctx_alloc();
+ if (test_schedule(ctx) < 0)
+ goto error;
test_factorize(ctx);
test_subset(ctx);
test_lift(ctx);