isl_local_space_offset: extract out isl_local_space_var_offset

[isl.git] / isl_schedule_constraints.c

/*
 * Copyright 2012      Ecole Normale Superieure
 * Copyright 2015-2016 Sven Verdoolaege
 *
 * Use of this software is governed by the MIT license
 *
 * Written by Sven Verdoolaege,
 * Ecole Normale Superieure, 45 rue d'Ulm, 75230 Paris, France
 */

#include <isl_schedule_constraints.h>
#include <isl/schedule.h>
#include <isl/space.h>
#include <isl/set.h>
#include <isl/map.h>
#include <isl/union_set.h>
#include <isl/union_map.h>
#include <isl/stream.h>

/* The constraints that need to be satisfied by a schedule on "domain".
 *
 * "context" specifies extra constraints on the parameters.
 *
 * "validity" constraints map domain elements i to domain elements
 * that should be scheduled after i.  (Hard constraint)
 * "proximity" constraints map domain elements i to domains elements
 * that should be scheduled as early as possible after i (or before i).
 * (Soft constraint)
 *
 * "condition" and "conditional_validity" constraints map possibly "tagged"
 * domain elements i -> s to "tagged" domain elements j -> t.
 * The elements of the "conditional_validity" constraints, but without the
 * tags (i.e., the elements i -> j) are treated as validity constraints,
 * except that during the construction of a tilable band,
 * the elements of the "conditional_validity" constraints may be violated
 * provided that all adjacent elements of the "condition" constraints
 * are local within the band.
 * A dependence is local within a band if domain and range are mapped
 * to the same schedule point by the band.
 */
struct isl_schedule_constraints {
        isl_union_set *domain;
        isl_set *context;

        isl_union_map *constraint[isl_edge_last + 1];
};

__isl_give isl_schedule_constraints *isl_schedule_constraints_copy(
        __isl_keep isl_schedule_constraints *sc)
{
        isl_ctx *ctx;
        isl_schedule_constraints *sc_copy;
        enum isl_edge_type i;

        ctx = isl_union_set_get_ctx(sc->domain);
        sc_copy = isl_calloc_type(ctx, struct isl_schedule_constraints);
        if (!sc_copy)
                return NULL;

        sc_copy->domain = isl_union_set_copy(sc->domain);
        sc_copy->context = isl_set_copy(sc->context);
        if (!sc_copy->domain || !sc_copy->context)
                return isl_schedule_constraints_free(sc_copy);

        for (i = isl_edge_first; i <= isl_edge_last; ++i) {
                sc_copy->constraint[i] = isl_union_map_copy(sc->constraint[i]);
                if (!sc_copy->constraint[i])
                        return isl_schedule_constraints_free(sc_copy);
        }

        return sc_copy;
}

/* Construct an empty (invalid) isl_schedule_constraints object.
 * The caller is responsible for setting the domain and initializing
 * all the other fields, e.g., by calling isl_schedule_constraints_init.
 */
static __isl_give isl_schedule_constraints *isl_schedule_constraints_alloc(
        isl_ctx *ctx)
{
        return isl_calloc_type(ctx, struct isl_schedule_constraints);
}

/* Initialize all the fields of "sc", except domain, which is assumed
 * to have been set by the caller.
 */
static __isl_give isl_schedule_constraints *isl_schedule_constraints_init(
        __isl_take isl_schedule_constraints *sc)
{
        isl_space *space;
        isl_union_map *empty;
        enum isl_edge_type i;

        if (!sc)
                return NULL;
        if (!sc->domain)
                return isl_schedule_constraints_free(sc);
        space = isl_union_set_get_space(sc->domain);
        if (!sc->context)
                sc->context = isl_set_universe(isl_space_copy(space));
        empty = isl_union_map_empty(space);
        for (i = isl_edge_first; i <= isl_edge_last; ++i) {
                if (sc->constraint[i])
                        continue;
                sc->constraint[i] = isl_union_map_copy(empty);
                if (!sc->constraint[i])
                        sc->domain = isl_union_set_free(sc->domain);
        }
        isl_union_map_free(empty);

        if (!sc->domain || !sc->context)
                return isl_schedule_constraints_free(sc);

        return sc;
}

/* Construct an isl_schedule_constraints object for computing a schedule
 * on "domain".  The initial object does not impose any constraints.
 */
__isl_give isl_schedule_constraints *isl_schedule_constraints_on_domain(
        __isl_take isl_union_set *domain)
{
        isl_ctx *ctx;
        isl_schedule_constraints *sc;

        if (!domain)
                return NULL;

        ctx = isl_union_set_get_ctx(domain);
        sc = isl_schedule_constraints_alloc(ctx);
        if (!sc)
                goto error;

        sc->domain = domain;
        return isl_schedule_constraints_init(sc);
error:
        isl_union_set_free(domain);
        return NULL;
}

/* Replace the domain of "sc" by "domain".
 */
static __isl_give isl_schedule_constraints *isl_schedule_constraints_set_domain(
        __isl_take isl_schedule_constraints *sc,
        __isl_take isl_union_set *domain)
{
        if (!sc || !domain)
                goto error;

        isl_union_set_free(sc->domain);
        sc->domain = domain;

        return sc;
error:
        isl_schedule_constraints_free(sc);
        isl_union_set_free(domain);
        return NULL;
}

/* Replace the context of "sc" by "context".
 */
__isl_give isl_schedule_constraints *isl_schedule_constraints_set_context(
        __isl_take isl_schedule_constraints *sc, __isl_take isl_set *context)
{
        if (!sc || !context)
                goto error;

        isl_set_free(sc->context);
        sc->context = context;

        return sc;
error:
        isl_schedule_constraints_free(sc);
        isl_set_free(context);
        return NULL;
}

/* Replace the constraints of type "type" in "sc" by "c".
 *
 * First detect any equality constraints that may be implicit in "c"
 * in order to try and improve the accuracy of the input (and therefore
 * also the output) of the isl_set_coefficients calls
 * that are eventually performed on (some of) these constraints.
 */
static __isl_give isl_schedule_constraints *isl_schedule_constraints_set(
        __isl_take isl_schedule_constraints *sc, enum isl_edge_type type,
        __isl_take isl_union_map *c)
{
        c = isl_union_map_detect_equalities(c);
        if (!sc || !c)
                goto error;

        isl_union_map_free(sc->constraint[type]);
        sc->constraint[type] = c;

        return sc;
error:
        isl_schedule_constraints_free(sc);
        isl_union_map_free(c);
        return NULL;
}

/* Replace the validity constraints of "sc" by "validity".
 */
__isl_give isl_schedule_constraints *isl_schedule_constraints_set_validity(
        __isl_take isl_schedule_constraints *sc,
        __isl_take isl_union_map *validity)
{
        return isl_schedule_constraints_set(sc, isl_edge_validity, validity);
}

/* Replace the coincidence constraints of "sc" by "coincidence".
 */
__isl_give isl_schedule_constraints *isl_schedule_constraints_set_coincidence(
        __isl_take isl_schedule_constraints *sc,
        __isl_take isl_union_map *coincidence)
{
        return isl_schedule_constraints_set(sc, isl_edge_coincidence,
                                                coincidence);
}

/* Replace the proximity constraints of "sc" by "proximity".
 */
__isl_give isl_schedule_constraints *isl_schedule_constraints_set_proximity(
        __isl_take isl_schedule_constraints *sc,
        __isl_take isl_union_map *proximity)
{
        return isl_schedule_constraints_set(sc, isl_edge_proximity, proximity);
}

/* Replace the conditional validity constraints of "sc" by "condition"
 * and "validity".
 */
__isl_give isl_schedule_constraints *
isl_schedule_constraints_set_conditional_validity(
        __isl_take isl_schedule_constraints *sc,
        __isl_take isl_union_map *condition,
        __isl_take isl_union_map *validity)
{
        sc = isl_schedule_constraints_set(sc, isl_edge_condition, condition);
        sc = isl_schedule_constraints_set(sc, isl_edge_conditional_validity,
                                                validity);
        return sc;
}

__isl_null isl_schedule_constraints *isl_schedule_constraints_free(
        __isl_take isl_schedule_constraints *sc)
{
        enum isl_edge_type i;

        if (!sc)
                return NULL;

        isl_union_set_free(sc->domain);
        isl_set_free(sc->context);
        for (i = isl_edge_first; i <= isl_edge_last; ++i)
                isl_union_map_free(sc->constraint[i]);

        free(sc);

        return NULL;
}

isl_ctx *isl_schedule_constraints_get_ctx(
        __isl_keep isl_schedule_constraints *sc)
{
        return sc ? isl_union_set_get_ctx(sc->domain) : NULL;
}

/* Return the domain of "sc".
 */
__isl_give isl_union_set *isl_schedule_constraints_get_domain(
        __isl_keep isl_schedule_constraints *sc)
{
        if (!sc)
                return NULL;

        return isl_union_set_copy(sc->domain);
}

/* Return the context of "sc".
 */
__isl_give isl_set *isl_schedule_constraints_get_context(
        __isl_keep isl_schedule_constraints *sc)
{
        if (!sc)
                return NULL;

        return isl_set_copy(sc->context);
}

/* Return the constraints of type "type" in "sc".
 */
__isl_give isl_union_map *isl_schedule_constraints_get(
        __isl_keep isl_schedule_constraints *sc, enum isl_edge_type type)
{
        if (!sc)
                return NULL;

        return isl_union_map_copy(sc->constraint[type]);
}

/* Return the validity constraints of "sc".
 */
__isl_give isl_union_map *isl_schedule_constraints_get_validity(
        __isl_keep isl_schedule_constraints *sc)
{
        return isl_schedule_constraints_get(sc, isl_edge_validity);
}

/* Return the coincidence constraints of "sc".
 */
__isl_give isl_union_map *isl_schedule_constraints_get_coincidence(
        __isl_keep isl_schedule_constraints *sc)
{
        return isl_schedule_constraints_get(sc, isl_edge_coincidence);
}

/* Return the proximity constraints of "sc".
 */
__isl_give isl_union_map *isl_schedule_constraints_get_proximity(
        __isl_keep isl_schedule_constraints *sc)
{
        return isl_schedule_constraints_get(sc, isl_edge_proximity);
}

/* Return the conditional validity constraints of "sc".
 */
__isl_give isl_union_map *isl_schedule_constraints_get_conditional_validity(
        __isl_keep isl_schedule_constraints *sc)
{
        return isl_schedule_constraints_get(sc, isl_edge_conditional_validity);
}

/* Return the conditions for the conditional validity constraints of "sc".
 */
__isl_give isl_union_map *
isl_schedule_constraints_get_conditional_validity_condition(
        __isl_keep isl_schedule_constraints *sc)
{
        return isl_schedule_constraints_get(sc, isl_edge_condition);
}

/* Add "c" to the constraints of type "type" in "sc".
 */
__isl_give isl_schedule_constraints *isl_schedule_constraints_add(
        __isl_take isl_schedule_constraints *sc, enum isl_edge_type type,
        __isl_take isl_union_map *c)
{
        if (!sc || !c)
                goto error;

        c = isl_union_map_union(sc->constraint[type], c);
        sc->constraint[type] = c;
        if (!c)
                return isl_schedule_constraints_free(sc);

        return sc;
error:
        isl_schedule_constraints_free(sc);
        isl_union_map_free(c);
        return NULL;
}

/* Can a schedule constraint of type "type" be tagged?
 */
static int may_be_tagged(enum isl_edge_type type)
{
        if (type == isl_edge_condition || type == isl_edge_conditional_validity)
                return 1;
        return 0;
}

/* Apply "umap" to the domains of the wrapped relations
 * inside the domain and range of "c".
 *
 * That is, for each map of the form
 *
 *      [D -> S] -> [E -> T]
 *
 * in "c", apply "umap" to D and E.
 *
 * D is exposed by currying the relation to
 *
 *      D -> [S -> [E -> T]]
 *
 * E is exposed by doing the same to the inverse of "c".
 */
static __isl_give isl_union_map *apply_factor_domain(
        __isl_take isl_union_map *c, __isl_keep isl_union_map *umap)
{
        c = isl_union_map_curry(c);
        c = isl_union_map_apply_domain(c, isl_union_map_copy(umap));
        c = isl_union_map_uncurry(c);

        c = isl_union_map_reverse(c);
        c = isl_union_map_curry(c);
        c = isl_union_map_apply_domain(c, isl_union_map_copy(umap));
        c = isl_union_map_uncurry(c);
        c = isl_union_map_reverse(c);

        return c;
}

/* Apply "umap" to domain and range of "c".
 * If "tag" is set, then "c" may contain tags and then "umap"
 * needs to be applied to the domains of the wrapped relations
 * inside the domain and range of "c".
 */
static __isl_give isl_union_map *apply(__isl_take isl_union_map *c,
        __isl_keep isl_union_map *umap, int tag)
{
        isl_union_map *t;

        if (tag)
                t = isl_union_map_copy(c);
        c = isl_union_map_apply_domain(c, isl_union_map_copy(umap));
        c = isl_union_map_apply_range(c, isl_union_map_copy(umap));
        if (!tag)
                return c;
        t = apply_factor_domain(t, umap);
        c = isl_union_map_union(c, t);
        return c;
}

/* Apply "umap" to the domain of the schedule constraints "sc".
 *
 * The two sides of the various schedule constraints are adjusted
 * accordingly.
 */
__isl_give isl_schedule_constraints *isl_schedule_constraints_apply(
        __isl_take isl_schedule_constraints *sc,
        __isl_take isl_union_map *umap)
{
        enum isl_edge_type i;

        if (!sc || !umap)
                goto error;

        for (i = isl_edge_first; i <= isl_edge_last; ++i) {
                int tag = may_be_tagged(i);

                sc->constraint[i] = apply(sc->constraint[i], umap, tag);
                if (!sc->constraint[i])
                        goto error;
        }
        sc->domain = isl_union_set_apply(sc->domain, umap);
        if (!sc->domain)
                return isl_schedule_constraints_free(sc);

        return sc;
error:
        isl_schedule_constraints_free(sc);
        isl_union_map_free(umap);
        return NULL;
}

/* An enumeration of the various keys that may appear in a YAML mapping
 * of an isl_schedule_constraints object.
 * The keys for the edge types are assumed to have the same values
 * as the edge types in isl_edge_type.
 */
enum isl_sc_key {
        isl_sc_key_error = -1,
        isl_sc_key_validity = isl_edge_validity,
        isl_sc_key_coincidence = isl_edge_coincidence,
        isl_sc_key_condition = isl_edge_condition,
        isl_sc_key_conditional_validity = isl_edge_conditional_validity,
        isl_sc_key_proximity = isl_edge_proximity,
        isl_sc_key_domain,
        isl_sc_key_context,
        isl_sc_key_end
};

/* Textual representations of the YAML keys for an isl_schedule_constraints
 * object.
 */
static char *key_str[] = {
        [isl_sc_key_validity] = "validity",
        [isl_sc_key_coincidence] = "coincidence",
        [isl_sc_key_condition] = "condition",
        [isl_sc_key_conditional_validity] = "conditional_validity",
        [isl_sc_key_proximity] = "proximity",
        [isl_sc_key_domain] = "domain",
        [isl_sc_key_context] = "context",
};

#undef BASE
#define BASE set
#include "print_yaml_field_templ.c"

#undef BASE
#define BASE union_set
#include "print_yaml_field_templ.c"

#undef BASE
#define BASE union_map
#include "print_yaml_field_templ.c"

/* Print a key, value pair for the edge of type "type" in "sc" to "p".
 *
 * If the edge relation is empty, then it is not printed since
 * an empty relation is the default value.
 */
static __isl_give isl_printer *print_constraint(__isl_take isl_printer *p,
        __isl_keep isl_schedule_constraints *sc, enum isl_edge_type type)
{
        isl_bool empty;

        empty = isl_union_map_plain_is_empty(sc->constraint[type]);
        if (empty < 0)
                return isl_printer_free(p);
        if (empty)
                return p;

        p = print_yaml_field_union_map(p, key_str[type], sc->constraint[type]);

        return p;
}

/* Print "sc" to "p"
 *
 * In particular, print the isl_schedule_constraints object as a YAML document.
 * Fields with values that are (obviously) equal to their default values
 * are not printed.
 */
__isl_give isl_printer *isl_printer_print_schedule_constraints(
        __isl_take isl_printer *p, __isl_keep isl_schedule_constraints *sc)
{
        isl_bool universe;

        if (!sc)
                return isl_printer_free(p);

        p = isl_printer_yaml_start_mapping(p);
        p = print_yaml_field_union_set(p, key_str[isl_sc_key_domain],
                                        sc->domain);
        universe = isl_set_plain_is_universe(sc->context);
        if (universe < 0)
                return isl_printer_free(p);
        if (!universe)
                p = print_yaml_field_set(p, key_str[isl_sc_key_context],
                                                sc->context);
        p = print_constraint(p, sc, isl_edge_validity);
        p = print_constraint(p, sc, isl_edge_proximity);
        p = print_constraint(p, sc, isl_edge_coincidence);
        p = print_constraint(p, sc, isl_edge_condition);
        p = print_constraint(p, sc, isl_edge_conditional_validity);
        p = isl_printer_yaml_end_mapping(p);

        return p;
}

#undef BASE
#define BASE schedule_constraints
#include <print_templ_yaml.c>

#undef KEY
#define KEY enum isl_sc_key
#undef KEY_ERROR
#define KEY_ERROR isl_sc_key_error
#undef KEY_END
#define KEY_END isl_sc_key_end
#include "extract_key.c"

#undef BASE
#define BASE set
#include "read_in_string_templ.c"

#undef BASE
#define BASE union_set
#include "read_in_string_templ.c"

#undef BASE
#define BASE union_map
#include "read_in_string_templ.c"

/* Read an isl_schedule_constraints object from "s".
 *
 * Start off with an empty (invalid) isl_schedule_constraints object and
 * then fill up the fields based on the input.
 * The input needs to contain at least a description of the domain.
 * The other fields are set to defaults by isl_schedule_constraints_init
 * if they are not specified in the input.
 */
__isl_give isl_schedule_constraints *isl_stream_read_schedule_constraints(
        isl_stream *s)
{
        isl_ctx *ctx;
        isl_schedule_constraints *sc;
        int more;
        int domain_set = 0;

        if (isl_stream_yaml_read_start_mapping(s))
                return NULL;

        ctx = isl_stream_get_ctx(s);
        sc = isl_schedule_constraints_alloc(ctx);
        while ((more = isl_stream_yaml_next(s)) > 0) {
                enum isl_sc_key key;
                isl_set *context;
                isl_union_set *domain;
                isl_union_map *constraints;

                key = get_key(s);
                if (isl_stream_yaml_next(s) < 0)
                        return isl_schedule_constraints_free(sc);
                switch (key) {
                case isl_sc_key_end:
                case isl_sc_key_error:
                        return isl_schedule_constraints_free(sc);
                case isl_sc_key_domain:
                        domain_set = 1;
                        domain = read_union_set(s);
                        sc = isl_schedule_constraints_set_domain(sc, domain);
                        if (!sc)
                                return NULL;
                        break;
                case isl_sc_key_context:
                        context = read_set(s);
                        sc = isl_schedule_constraints_set_context(sc, context);
                        if (!sc)
                                return NULL;
                        break;
                case isl_sc_key_validity:
                case isl_sc_key_coincidence:
                case isl_sc_key_condition:
                case isl_sc_key_conditional_validity:
                case isl_sc_key_proximity:
                        constraints = read_union_map(s);
                        sc = isl_schedule_constraints_set(sc, key, constraints);
                        if (!sc)
                                return NULL;
                        break;
                }
        }
        if (more < 0)
                return isl_schedule_constraints_free(sc);

        if (isl_stream_yaml_read_end_mapping(s) < 0) {
                isl_stream_error(s, NULL, "unexpected extra elements");
                return isl_schedule_constraints_free(sc);
        }

        if (!domain_set) {
                isl_stream_error(s, NULL, "no domain specified");
                return isl_schedule_constraints_free(sc);
        }

        return isl_schedule_constraints_init(sc);
}

/* Read an isl_schedule_constraints object from the file "input".
 */
__isl_give isl_schedule_constraints *isl_schedule_constraints_read_from_file(
        isl_ctx *ctx, FILE *input)
{
        struct isl_stream *s;
        isl_schedule_constraints *sc;

        s = isl_stream_new_file(ctx, input);
        if (!s)
                return NULL;
        sc = isl_stream_read_schedule_constraints(s);
        isl_stream_free(s);

        return sc;
}

/* Read an isl_schedule_constraints object from the string "str".
 */
__isl_give isl_schedule_constraints *isl_schedule_constraints_read_from_str(
        isl_ctx *ctx, const char *str)
{
        struct isl_stream *s;
        isl_schedule_constraints *sc;

        s = isl_stream_new_str(ctx, str);
        if (!s)
                return NULL;
        sc = isl_stream_read_schedule_constraints(s);
        isl_stream_free(s);

        return sc;
}

/* Align the parameters of the fields of "sc".
 */
__isl_give isl_schedule_constraints *
isl_schedule_constraints_align_params(__isl_take isl_schedule_constraints *sc)
{
        isl_space *space;
        enum isl_edge_type i;

        if (!sc)
                return NULL;

        space = isl_union_set_get_space(sc->domain);
        space = isl_space_align_params(space, isl_set_get_space(sc->context));
        for (i = isl_edge_first; i <= isl_edge_last; ++i)
                space = isl_space_align_params(space,
                                    isl_union_map_get_space(sc->constraint[i]));

        for (i = isl_edge_first; i <= isl_edge_last; ++i) {
                sc->constraint[i] = isl_union_map_align_params(
                                    sc->constraint[i], isl_space_copy(space));
                if (!sc->constraint[i])
                        space = isl_space_free(space);
        }
        sc->context = isl_set_align_params(sc->context, isl_space_copy(space));
        sc->domain = isl_union_set_align_params(sc->domain, space);
        if (!sc->context || !sc->domain)
                return isl_schedule_constraints_free(sc);

        return sc;
}

/* Add the number of basic maps in "map" to *n.
 */
static isl_stat add_n_basic_map(__isl_take isl_map *map, void *user)
{
        int *n = user;
        isl_size n_basic_map;

        n_basic_map = isl_map_n_basic_map(map);
        *n += n_basic_map;
        isl_map_free(map);

        return n_basic_map < 0 ? isl_stat_error : isl_stat_ok;
}

/* Return the total number of isl_basic_maps in the constraints of "sc".
 * Return -1 on error.
 */
int isl_schedule_constraints_n_basic_map(
        __isl_keep isl_schedule_constraints *sc)
{
        enum isl_edge_type i;
        int n = 0;

        if (!sc)
                return -1;
        for (i = isl_edge_first; i <= isl_edge_last; ++i)
                if (isl_union_map_foreach_map(sc->constraint[i],
                                                &add_n_basic_map, &n) < 0)
                        return -1;

        return n;
}

/* Return the total number of isl_maps in the constraints of "sc".
 */
isl_size isl_schedule_constraints_n_map(__isl_keep isl_schedule_constraints *sc)
{
        enum isl_edge_type i;
        int n = 0;

        for (i = isl_edge_first; i <= isl_edge_last; ++i) {
                isl_size n_i;

                n_i = isl_union_map_n_map(sc->constraint[i]);
                if (n_i < 0)
                        return isl_size_error;
                n += n_i;
        }

        return n;
}