isl_schedule_node.c: collect_filter_prefix: allow caller to initialize filter

[isl.git] / isl_schedule_band.c

/*
 * Copyright 2013-2014 Ecole Normale Superieure
 * Copyright 2014      INRIA Rocquencourt
 *
 * Use of this software is governed by the MIT license
 *
 * Written by Sven Verdoolaege,
 * Ecole Normale Superieure, 45 rue d'Ulm, 75230 Paris, France
 * and Inria Paris - Rocquencourt, Domaine de Voluceau - Rocquencourt,
 * B.P. 105 - 78153 Le Chesnay, France
 */

#include <string.h>
#include <isl/map.h>
#include <isl/schedule_node.h>
#include <isl_schedule_band.h>
#include <isl_schedule_private.h>

isl_ctx *isl_schedule_band_get_ctx(__isl_keep isl_schedule_band *band)
{
        return band ? isl_multi_union_pw_aff_get_ctx(band->mupa) : NULL;
}

/* Return a new uninitialized isl_schedule_band.
 */
static __isl_give isl_schedule_band *isl_schedule_band_alloc(isl_ctx *ctx)
{
        isl_schedule_band *band;

        band = isl_calloc_type(ctx, isl_schedule_band);
        if (!band)
                return NULL;

        band->ref = 1;

        return band;
}

/* Return a new isl_schedule_band with partial schedule "mupa".
 * First replace "mupa" by its greatest integer part to ensure
 * that the schedule is always integral.
 * The band is not marked permutable, the dimensions are not
 * marked coincident and the AST build options are empty.
 * Since there are no build options, the node is not anchored.
 */
__isl_give isl_schedule_band *isl_schedule_band_from_multi_union_pw_aff(
        __isl_take isl_multi_union_pw_aff *mupa)
{
        isl_ctx *ctx;
        isl_schedule_band *band;
        isl_space *space;

        mupa = isl_multi_union_pw_aff_floor(mupa);
        if (!mupa)
                return NULL;
        ctx = isl_multi_union_pw_aff_get_ctx(mupa);
        band = isl_schedule_band_alloc(ctx);
        if (!band)
                goto error;

        band->n = isl_multi_union_pw_aff_dim(mupa, isl_dim_set);
        band->coincident = isl_calloc_array(ctx, int, band->n);
        band->mupa = mupa;
        space = isl_space_params_alloc(ctx, 0);
        band->ast_build_options = isl_union_set_empty(space);
        band->anchored = 0;

        if ((band->n && !band->coincident) || !band->ast_build_options)
                return isl_schedule_band_free(band);

        return band;
error:
        isl_multi_union_pw_aff_free(mupa);
        return NULL;
}

/* Create a duplicate of the given isl_schedule_band.
 */
__isl_give isl_schedule_band *isl_schedule_band_dup(
        __isl_keep isl_schedule_band *band)
{
        int i;
        isl_ctx *ctx;
        isl_schedule_band *dup;

        if (!band)
                return NULL;

        ctx = isl_schedule_band_get_ctx(band);
        dup = isl_schedule_band_alloc(ctx);
        if (!dup)
                return NULL;

        dup->n = band->n;
        dup->coincident = isl_alloc_array(ctx, int, band->n);
        if (band->n && !dup->coincident)
                return isl_schedule_band_free(dup);

        for (i = 0; i < band->n; ++i)
                dup->coincident[i] = band->coincident[i];
        dup->permutable = band->permutable;

        dup->mupa = isl_multi_union_pw_aff_copy(band->mupa);
        dup->ast_build_options = isl_union_set_copy(band->ast_build_options);
        if (!dup->mupa || !dup->ast_build_options)
                return isl_schedule_band_free(dup);

        if (band->loop_type) {
                dup->loop_type = isl_alloc_array(ctx,
                                            enum isl_ast_loop_type, band->n);
                if (band->n && !dup->loop_type)
                        return isl_schedule_band_free(dup);
                for (i = 0; i < band->n; ++i)
                        dup->loop_type[i] = band->loop_type[i];
        }
        if (band->isolate_loop_type) {
                dup->isolate_loop_type = isl_alloc_array(ctx,
                                            enum isl_ast_loop_type, band->n);
                if (band->n && !dup->isolate_loop_type)
                        return isl_schedule_band_free(dup);
                for (i = 0; i < band->n; ++i)
                        dup->isolate_loop_type[i] = band->isolate_loop_type[i];
        }

        return dup;
}

/* Return an isl_schedule_band that is equal to "band" and that has only
 * a single reference.
 */
__isl_give isl_schedule_band *isl_schedule_band_cow(
        __isl_take isl_schedule_band *band)
{
        if (!band)
                return NULL;

        if (band->ref == 1)
                return band;
        band->ref--;
        return isl_schedule_band_dup(band);
}

/* Return a new reference to "band".
 */
__isl_give isl_schedule_band *isl_schedule_band_copy(
        __isl_keep isl_schedule_band *band)
{
        if (!band)
                return NULL;

        band->ref++;
        return band;
}

/* Free a reference to "band" and return NULL.
 */
__isl_null isl_schedule_band *isl_schedule_band_free(
        __isl_take isl_schedule_band *band)
{
        if (!band)
                return NULL;

        if (--band->ref > 0)
                return NULL;

        isl_multi_union_pw_aff_free(band->mupa);
        isl_union_set_free(band->ast_build_options);
        free(band->loop_type);
        free(band->isolate_loop_type);
        free(band->coincident);
        free(band);

        return NULL;
}

/* Are "band1" and "band2" obviously equal?
 */
int isl_schedule_band_plain_is_equal(__isl_keep isl_schedule_band *band1,
        __isl_keep isl_schedule_band *band2)
{
        int i;
        int equal;

        if (!band1 || !band2)
                return -1;
        if (band1 == band2)
                return 1;

        if (band1->n != band2->n)
                return 0;
        for (i = 0; i < band1->n; ++i)
                if (band1->coincident[i] != band2->coincident[i])
                        return 0;
        if (band1->permutable != band2->permutable)
                return 0;

        equal = isl_multi_union_pw_aff_plain_is_equal(band1->mupa, band2->mupa);
        if (equal < 0 || !equal)
                return equal;

        if (!band1->loop_type != !band2->loop_type)
                return 0;
        if (band1->loop_type)
                for (i = 0; i < band1->n; ++i)
                        if (band1->loop_type[i] != band2->loop_type[i])
                                return 0;

        if (!band1->isolate_loop_type != !band2->isolate_loop_type)
                return 0;
        if (band1->isolate_loop_type)
                for (i = 0; i < band1->n; ++i)
                        if (band1->isolate_loop_type[i] !=
                                                band2->isolate_loop_type[i])
                                return 0;

        return isl_union_set_is_equal(band1->ast_build_options,
                                        band2->ast_build_options);
}

/* Return the number of scheduling dimensions in the band.
 */
int isl_schedule_band_n_member(__isl_keep isl_schedule_band *band)
{
        return band ? band->n : 0;
}

/* Is the given scheduling dimension coincident within the band and
 * with respect to the coincidence constraints?
 */
int isl_schedule_band_member_get_coincident(__isl_keep isl_schedule_band *band,
        int pos)
{
        if (!band)
                return -1;

        if (pos < 0 || pos >= band->n)
                isl_die(isl_schedule_band_get_ctx(band), isl_error_invalid,
                        "invalid member position", return -1);

        return band->coincident[pos];
}

/* Mark the given scheduling dimension as being coincident or not
 * according to "coincident".
 */
__isl_give isl_schedule_band *isl_schedule_band_member_set_coincident(
        __isl_take isl_schedule_band *band, int pos, int coincident)
{
        if (!band)
                return NULL;
        if (isl_schedule_band_member_get_coincident(band, pos) == coincident)
                return band;
        band = isl_schedule_band_cow(band);
        if (!band)
                return NULL;

        if (pos < 0 || pos >= band->n)
                isl_die(isl_schedule_band_get_ctx(band), isl_error_invalid,
                        "invalid member position",
                        isl_schedule_band_free(band));

        band->coincident[pos] = coincident;

        return band;
}

/* Is the schedule band mark permutable?
 */
int isl_schedule_band_get_permutable(__isl_keep isl_schedule_band *band)
{
        if (!band)
                return -1;
        return band->permutable;
}

/* Mark the schedule band permutable or not according to "permutable"?
 */
__isl_give isl_schedule_band *isl_schedule_band_set_permutable(
        __isl_take isl_schedule_band *band, int permutable)
{
        if (!band)
                return NULL;
        if (band->permutable == permutable)
                return band;
        band = isl_schedule_band_cow(band);
        if (!band)
                return NULL;

        band->permutable = permutable;

        return band;
}

/* Is the band node "node" anchored?  That is, does it reference
 * the outer band nodes?
 */
int isl_schedule_band_is_anchored(__isl_keep isl_schedule_band *band)
{
        return band ? band->anchored : -1;
}

/* Return the schedule space of the band.
 */
__isl_give isl_space *isl_schedule_band_get_space(
        __isl_keep isl_schedule_band *band)
{
        if (!band)
                return NULL;
        return isl_multi_union_pw_aff_get_space(band->mupa);
}

/* Return the schedule of the band in isolation.
 */
__isl_give isl_multi_union_pw_aff *isl_schedule_band_get_partial_schedule(
        __isl_keep isl_schedule_band *band)
{
        return band ? isl_multi_union_pw_aff_copy(band->mupa) : NULL;
}

/* Return the loop AST generation type for the band member of "band"
 * at position "pos".
 */
enum isl_ast_loop_type isl_schedule_band_member_get_ast_loop_type(
        __isl_keep isl_schedule_band *band, int pos)
{
        if (!band)
                return isl_ast_loop_error;

        if (pos < 0 || pos >= band->n)
                isl_die(isl_schedule_band_get_ctx(band), isl_error_invalid,
                        "invalid member position", return -1);

        if (!band->loop_type)
                return isl_ast_loop_default;

        return band->loop_type[pos];
}

/* Set the loop AST generation type for the band member of "band"
 * at position "pos" to "type".
 */
__isl_give isl_schedule_band *isl_schedule_band_member_set_ast_loop_type(
        __isl_take isl_schedule_band *band, int pos,
        enum isl_ast_loop_type type)
{
        if (!band)
                return NULL;
        if (isl_schedule_band_member_get_ast_loop_type(band, pos) == type)
                return band;

        if (pos < 0 || pos >= band->n)
                isl_die(isl_schedule_band_get_ctx(band), isl_error_invalid,
                        "invalid member position",
                        isl_schedule_band_free(band));

        band = isl_schedule_band_cow(band);
        if (!band)
                return isl_schedule_band_free(band);

        if (!band->loop_type) {
                isl_ctx *ctx;

                ctx = isl_schedule_band_get_ctx(band);
                band->loop_type = isl_calloc_array(ctx,
                                            enum isl_ast_loop_type, band->n);
                if (band->n && !band->loop_type)
                        return isl_schedule_band_free(band);
        }

        band->loop_type[pos] = type;

        return band;
}

/* Return the loop AST generation type for the band member of "band"
 * at position "pos" for the part that has been isolated by the isolate option.
 */
enum isl_ast_loop_type isl_schedule_band_member_get_isolate_ast_loop_type(
        __isl_keep isl_schedule_band *band, int pos)
{
        if (!band)
                return isl_ast_loop_error;

        if (pos < 0 || pos >= band->n)
                isl_die(isl_schedule_band_get_ctx(band), isl_error_invalid,
                        "invalid member position", return -1);

        if (!band->isolate_loop_type)
                return isl_ast_loop_default;

        return band->isolate_loop_type[pos];
}

/* Set the loop AST generation type for the band member of "band"
 * at position "pos" to "type" for the part that has been isolated
 * by the isolate option.
 */
__isl_give isl_schedule_band *
isl_schedule_band_member_set_isolate_ast_loop_type(
        __isl_take isl_schedule_band *band, int pos,
        enum isl_ast_loop_type type)
{
        if (!band)
                return NULL;
        if (isl_schedule_band_member_get_isolate_ast_loop_type(band, pos) ==
                                                                        type)
                return band;

        if (pos < 0 || pos >= band->n)
                isl_die(isl_schedule_band_get_ctx(band), isl_error_invalid,
                        "invalid member position",
                        isl_schedule_band_free(band));

        band = isl_schedule_band_cow(band);
        if (!band)
                return isl_schedule_band_free(band);

        if (!band->isolate_loop_type) {
                isl_ctx *ctx;

                ctx = isl_schedule_band_get_ctx(band);
                band->isolate_loop_type = isl_calloc_array(ctx,
                                            enum isl_ast_loop_type, band->n);
                if (band->n && !band->isolate_loop_type)
                        return isl_schedule_band_free(band);
        }

        band->isolate_loop_type[pos] = type;

        return band;
}

static const char *option_str[] = {
        [isl_ast_loop_atomic] = "atomic",
        [isl_ast_loop_unroll] = "unroll",
        [isl_ast_loop_separate] = "separate"
};

/* Given a parameter space "space", extend it to a set space
 *
 *      { type[x] }
 *
 * or
 *
 *      { [isolate[] -> type[x]] }
 *
 * depending on whether "isolate" is set.
 * These can be used to encode loop AST generation options of the given type.
 */
static __isl_give isl_space *loop_type_space(__isl_take isl_space *space,
        enum isl_ast_loop_type type, int isolate)
{
        const char *name;

        name = option_str[type];
        space = isl_space_set_from_params(space);
        space = isl_space_add_dims(space, isl_dim_set, 1);
        space = isl_space_set_tuple_name(space, isl_dim_set, name);
        if (!isolate)
                return space;
        space = isl_space_from_range(space);
        space = isl_space_set_tuple_name(space, isl_dim_in, "isolate");
        space = isl_space_wrap(space);

        return space;
}

/* Add encodings of the "n" loop AST generation options "type" to "options".
 * If "isolate" is set, then these options refer to the isolated part.
 *
 * In particular, for each sequence of consecutive identical types "t",
 * different from the default, add an option
 *
 *      { t[x] : first <= x <= last }
 *
 * or
 *
 *      { [isolate[] -> t[x]] : first <= x <= last }
 */
static __isl_give isl_union_set *add_loop_types(
        __isl_take isl_union_set *options, int n, enum isl_ast_loop_type *type,
        int isolate)
{
        int i;
        isl_ctx *ctx;

        if (!type)
                return options;
        if (!options)
                return NULL;

        ctx = isl_union_set_get_ctx(options);
        for (i = 0; i < n; ++i) {
                int first;
                isl_space *space;
                isl_set *option;

                if (type[i] == isl_ast_loop_default)
                        continue;

                first = i;
                while (i + 1 < n && type[i + 1] == type[i])
                        ++i;

                space = isl_union_set_get_space(options);
                space = loop_type_space(space, type[i], isolate);
                option = isl_set_universe(space);
                option = isl_set_lower_bound_si(option, isl_dim_set, 0, first);
                option = isl_set_upper_bound_si(option, isl_dim_set, 0, i);
                options = isl_union_set_add_set(options, option);
        }

        return options;
}

/* Return the AST build options associated to "band".
 */
__isl_give isl_union_set *isl_schedule_band_get_ast_build_options(
        __isl_keep isl_schedule_band *band)
{
        isl_union_set *options;

        if (!band)
                return NULL;

        options = isl_union_set_copy(band->ast_build_options);
        options = add_loop_types(options, band->n, band->loop_type, 0);
        options = add_loop_types(options, band->n, band->isolate_loop_type, 1);

        return options;
}

/* Does "uset" contain any set that satisfies "is"?
 * "is" is assumed to set its integer argument to 1 if it is satisfied.
 */
static int has_any(__isl_keep isl_union_set *uset,
        int (*is)(__isl_take isl_set *set, void *user))
{
        int found = 0;

        if (isl_union_set_foreach_set(uset, is, &found) < 0 && !found)
                return -1;

        return found;
}

/* Does "set" live in a space of the form
 *
 *      isolate[[...] -> [...]]
 *
 * ?
 *
 * If so, set *found and abort the search.
 */
static int is_isolate(__isl_take isl_set *set, void *user)
{
        int *found = user;

        if (isl_set_has_tuple_name(set)) {
                const char *name;
                name = isl_set_get_tuple_name(set);
                if (isl_set_is_wrapping(set) && !strcmp(name, "isolate"))
                        *found = 1;
        }
        isl_set_free(set);

        return *found ? -1 : 0;
}

/* Does "options" include an option of the ofrm
 *
 *      isolate[[...] -> [...]]
 *
 * ?
 */
static int has_isolate_option(__isl_keep isl_union_set *options)
{
        return has_any(options, &is_isolate);
}

/* Does "set" encode a loop AST generation option?
 */
static int is_loop_type_option(__isl_take isl_set *set, void *user)
{
        int *found = user;

        if (isl_set_dim(set, isl_dim_set) == 1 &&
            isl_set_has_tuple_name(set)) {
                const char *name;
                enum isl_ast_loop_type type;
                name = isl_set_get_tuple_name(set);
                for (type = isl_ast_loop_atomic;
                    type <= isl_ast_loop_separate; ++type) {
                        if (strcmp(name, option_str[type]))
                                continue;
                        *found = 1;
                        break;
                }
        }
        isl_set_free(set);

        return *found ? -1 : 0;
}

/* Does "set" encode a loop AST generation option for the isolated part?
 * That is, is of the form
 *
 *      { [isolate[] -> t[x]] }
 *
 * with t equal to "atomic", "unroll" or "separate"?
 */
static int is_isolate_loop_type_option(__isl_take isl_set *set, void *user)
{
        int *found = user;
        const char *name;
        enum isl_ast_loop_type type;
        isl_map *map;

        if (!isl_set_is_wrapping(set)) {
                isl_set_free(set);
                return 0;
        }
        map = isl_set_unwrap(set);
        if (!isl_map_has_tuple_name(map, isl_dim_in) ||
            !isl_map_has_tuple_name(map, isl_dim_out)) {
                isl_map_free(map);
                return 0;
        }
        name = isl_map_get_tuple_name(map, isl_dim_in);
        if (!strcmp(name, "isolate")) {
                name = isl_map_get_tuple_name(map, isl_dim_out);
                for (type = isl_ast_loop_atomic;
                    type <= isl_ast_loop_separate; ++type) {
                        if (strcmp(name, option_str[type]))
                                continue;
                        *found = 1;
                        break;
                }
        }
        isl_map_free(map);

        return *found ? -1 : 0;
}

/* Does "options" encode any loop AST generation options
 * for the isolated part?
 */
static int has_isolate_loop_type_options(__isl_keep isl_union_set *options)
{
        return has_any(options, &is_isolate_loop_type_option);
}

/* Does "options" encode any loop AST generation options?
 */
static int has_loop_type_options(__isl_keep isl_union_set *options)
{
        return has_any(options, &is_loop_type_option);
}

/* Extract the loop AST generation type for the band member
 * at position "pos" from "options".
 * If "isolate" is set, then extract the loop types for the isolated part.
 */
static enum isl_ast_loop_type extract_loop_type(
        __isl_keep isl_union_set *options, int pos, int isolate)
{
        isl_ctx *ctx;
        enum isl_ast_loop_type type, res = isl_ast_loop_default;

        ctx = isl_union_set_get_ctx(options);
        for (type = isl_ast_loop_atomic;
            type <= isl_ast_loop_separate; ++type) {
                isl_space *space;
                isl_set *option;
                int empty;

                space = isl_union_set_get_space(options);
                space = loop_type_space(space, type, isolate);
                option = isl_union_set_extract_set(options, space);
                option = isl_set_fix_si(option, isl_dim_set, 0, pos);
                empty = isl_set_is_empty(option);
                isl_set_free(option);

                if (empty < 0)
                        return isl_ast_loop_error;
                if (empty)
                        continue;
                if (res != isl_ast_loop_default)
                        isl_die(ctx, isl_error_invalid,
                                "conflicting loop type options",
                                return isl_ast_loop_error);
                res = type;
        }

        return res;
}

/* Extract the loop AST generation types for the members of "band"
 * from "options" and store them in band->loop_type.
 * Return -1 on error.
 */
static int extract_loop_types(__isl_keep isl_schedule_band *band,
        __isl_keep isl_union_set *options)
{
        int i;

        if (!band->loop_type) {
                isl_ctx *ctx = isl_schedule_band_get_ctx(band);
                band->loop_type = isl_alloc_array(ctx,
                                            enum isl_ast_loop_type, band->n);
                if (band->n && !band->loop_type)
                        return -1;
        }
        for (i = 0; i < band->n; ++i) {
                band->loop_type[i] = extract_loop_type(options, i, 0);
                if (band->loop_type[i] == isl_ast_loop_error)
                        return -1;
        }

        return 0;
}

/* Extract the loop AST generation types for the members of "band"
 * from "options" for the isolated part and
 * store them in band->isolate_loop_type.
 * Return -1 on error.
 */
static int extract_isolate_loop_types(__isl_keep isl_schedule_band *band,
        __isl_keep isl_union_set *options)
{
        int i;

        if (!band->isolate_loop_type) {
                isl_ctx *ctx = isl_schedule_band_get_ctx(band);
                band->isolate_loop_type = isl_alloc_array(ctx,
                                            enum isl_ast_loop_type, band->n);
                if (band->n && !band->isolate_loop_type)
                        return -1;
        }
        for (i = 0; i < band->n; ++i) {
                band->isolate_loop_type[i] = extract_loop_type(options, i, 1);
                if (band->isolate_loop_type[i] == isl_ast_loop_error)
                        return -1;
        }

        return 0;
}

/* Construct universe sets of the spaces that encode loop AST generation
 * types (for the isolated part if "isolate" is set).  That is, construct
 *
 *      { atomic[x]; separate[x]; unroll[x] }
 *
 * or
 *
 *      { [isolate[] -> atomic[x]]; [isolate[] -> separate[x]];
 *        [isolate[] -> unroll[x]] }
 */
static __isl_give isl_union_set *loop_types(__isl_take isl_space *space,
        int isolate)
{
        enum isl_ast_loop_type type;
        isl_union_set *types;

        types = isl_union_set_empty(space);
        for (type = isl_ast_loop_atomic;
            type <= isl_ast_loop_separate; ++type) {
                isl_set *set;

                space = isl_union_set_get_space(types);
                space = loop_type_space(space, type, isolate);
                set = isl_set_universe(space);
                types = isl_union_set_add_set(types, set);
        }

        return types;
}

/* Remove all elements from spaces that encode loop AST generation types
 * from "options".
 */
static __isl_give isl_union_set *clear_loop_types(
        __isl_take isl_union_set *options)
{
        isl_union_set *types;

        types = loop_types(isl_union_set_get_space(options), 0);
        options = isl_union_set_subtract(options, types);

        return options;
}

/* Remove all elements from spaces that encode loop AST generation types
 * for the isolated part from "options".
 */
static __isl_give isl_union_set *clear_isolate_loop_types(
        __isl_take isl_union_set *options)
{
        isl_union_set *types;

        types = loop_types(isl_union_set_get_space(options), 1);
        options = isl_union_set_subtract(options, types);

        return options;
}

/* Replace the AST build options associated to "band" by "options".
 * If there are any loop AST generation type options, then they
 * are extracted and stored in band->loop_type.  Otherwise,
 * band->loop_type is removed to indicate that the default applies
 * to all members.  Similarly for the loop AST generation type options
 * for the isolated part, which are stored in band->isolate_loop_type.
 * The remaining options are stored in band->ast_build_options.
 *
 * Set anchored if the options include an isolate option since the
 * domain of the wrapped map references the outer band node schedules.
 */
__isl_give isl_schedule_band *isl_schedule_band_set_ast_build_options(
        __isl_take isl_schedule_band *band, __isl_take isl_union_set *options)
{
        int has_isolate, has_loop_type, has_isolate_loop_type;

        band = isl_schedule_band_cow(band);
        if (!band || !options)
                goto error;
        has_isolate = has_isolate_option(options);
        if (has_isolate < 0)
                goto error;
        has_loop_type = has_loop_type_options(options);
        if (has_loop_type < 0)
                goto error;
        has_isolate_loop_type = has_isolate_loop_type_options(options);
        if (has_isolate_loop_type < 0)
                goto error;

        if (!has_loop_type) {
                free(band->loop_type);
                band->loop_type = NULL;
        } else {
                if (extract_loop_types(band, options) < 0)
                        goto error;
                options = clear_loop_types(options);
                if (!options)
                        goto error;
        }

        if (!has_isolate_loop_type) {
                free(band->isolate_loop_type);
                band->isolate_loop_type = NULL;
        } else {
                if (extract_isolate_loop_types(band, options) < 0)
                        goto error;
                options = clear_isolate_loop_types(options);
                if (!options)
                        goto error;
        }

        isl_union_set_free(band->ast_build_options);
        band->ast_build_options = options;
        band->anchored = has_isolate;

        return band;
error:
        isl_schedule_band_free(band);
        isl_union_set_free(options);
        return NULL;
}

/* Multiply the partial schedule of "band" with the factors in "mv".
 * Replace the result by its greatest integer part to ensure
 * that the schedule is always integral.
 */
__isl_give isl_schedule_band *isl_schedule_band_scale(
        __isl_take isl_schedule_band *band, __isl_take isl_multi_val *mv)
{
        band = isl_schedule_band_cow(band);
        if (!band || !mv)
                goto error;
        band->mupa = isl_multi_union_pw_aff_scale_multi_val(band->mupa, mv);
        band->mupa = isl_multi_union_pw_aff_floor(band->mupa);
        if (!band->mupa)
                return isl_schedule_band_free(band);
        return band;
error:
        isl_schedule_band_free(band);
        isl_multi_val_free(mv);
        return NULL;
}

/* Divide the partial schedule of "band" by the factors in "mv".
 * Replace the result by its greatest integer part to ensure
 * that the schedule is always integral.
 */
__isl_give isl_schedule_band *isl_schedule_band_scale_down(
        __isl_take isl_schedule_band *band, __isl_take isl_multi_val *mv)
{
        band = isl_schedule_band_cow(band);
        if (!band || !mv)
                goto error;
        band->mupa = isl_multi_union_pw_aff_scale_down_multi_val(band->mupa,
                                                                mv);
        band->mupa = isl_multi_union_pw_aff_floor(band->mupa);
        if (!band->mupa)
                return isl_schedule_band_free(band);
        return band;
error:
        isl_schedule_band_free(band);
        isl_multi_val_free(mv);
        return NULL;
}

/* Given the schedule of a band, construct the corresponding
 * schedule for the tile loops based on the given tile sizes
 * and return the result.
 *
 * If the scale tile loops options is set, then the tile loops
 * are scaled by the tile sizes.
 *
 * That is replace each schedule dimension "i" by either
 * "floor(i/s)" or "s * floor(i/s)".
 */
static isl_multi_union_pw_aff *isl_multi_union_pw_aff_tile(
        __isl_take isl_multi_union_pw_aff *sched,
        __isl_take isl_multi_val *sizes)
{
        isl_ctx *ctx;
        int i, n;
        isl_val *v;
        int scale;

        ctx = isl_multi_val_get_ctx(sizes);
        scale = isl_options_get_tile_scale_tile_loops(ctx);

        n = isl_multi_union_pw_aff_dim(sched, isl_dim_set);
        for (i = 0; i < n; ++i) {
                isl_union_pw_aff *upa;

                upa = isl_multi_union_pw_aff_get_union_pw_aff(sched, i);
                v = isl_multi_val_get_val(sizes, i);

                upa = isl_union_pw_aff_scale_down_val(upa, isl_val_copy(v));
                upa = isl_union_pw_aff_floor(upa);
                if (scale)
                        upa = isl_union_pw_aff_scale_val(upa, isl_val_copy(v));
                isl_val_free(v);

                sched = isl_multi_union_pw_aff_set_union_pw_aff(sched, i, upa);
        }

        isl_multi_val_free(sizes);
        return sched;
}

/* Replace "band" by a band corresponding to the tile loops of a tiling
 * with the given tile sizes.
 */
__isl_give isl_schedule_band *isl_schedule_band_tile(
        __isl_take isl_schedule_band *band, __isl_take isl_multi_val *sizes)
{
        band = isl_schedule_band_cow(band);
        if (!band || !sizes)
                goto error;
        band->mupa = isl_multi_union_pw_aff_tile(band->mupa, sizes);
        if (!band->mupa)
                return isl_schedule_band_free(band);
        return band;
error:
        isl_schedule_band_free(band);
        isl_multi_val_free(sizes);
        return NULL;
}

/* Replace "band" by a band corresponding to the point loops of a tiling
 * with the given tile sizes.
 * "tile" is the corresponding tile loop band.
 *
 * If the shift point loops option is set, then the point loops
 * are shifted to start at zero.  That is, each schedule dimension "i"
 * is replaced by "i - s * floor(i/s)".
 * The expression "floor(i/s)" (or "s * floor(i/s)") is extracted from
 * the tile band.
 *
 * Otherwise, the band is left untouched.
 */
__isl_give isl_schedule_band *isl_schedule_band_point(
        __isl_take isl_schedule_band *band, __isl_keep isl_schedule_band *tile,
        __isl_take isl_multi_val *sizes)
{
        isl_ctx *ctx;
        isl_multi_union_pw_aff *scaled;

        if (!band || !sizes)
                goto error;

        ctx = isl_schedule_band_get_ctx(band);
        if (!isl_options_get_tile_shift_point_loops(ctx)) {
                isl_multi_val_free(sizes);
                return band;
        }
        band = isl_schedule_band_cow(band);
        if (!band)
                goto error;

        scaled = isl_schedule_band_get_partial_schedule(tile);
        if (!isl_options_get_tile_scale_tile_loops(ctx))
                scaled = isl_multi_union_pw_aff_scale_multi_val(scaled, sizes);
        else
                isl_multi_val_free(sizes);
        band->mupa = isl_multi_union_pw_aff_sub(band->mupa, scaled);
        if (!band->mupa)
                return isl_schedule_band_free(band);
        return band;
error:
        isl_schedule_band_free(band);
        isl_multi_val_free(sizes);
        return NULL;
}

/* Drop the "n" dimensions starting at "pos" from "band".
 *
 * We apply the transformation even if "n" is zero to ensure consistent
 * behavior with respect to changes in the schedule space.
 *
 * The loop AST generation types for the isolated part become
 * meaningless after dropping dimensions, so we remove them.
 */
__isl_give isl_schedule_band *isl_schedule_band_drop(
        __isl_take isl_schedule_band *band, int pos, int n)
{
        int i;

        if (pos < 0 || n < 0 || pos + n > band->n)
                isl_die(isl_schedule_band_get_ctx(band), isl_error_internal,
                        "range out of bounds",
                        return isl_schedule_band_free(band));

        band = isl_schedule_band_cow(band);
        if (!band)
                return NULL;

        band->mupa = isl_multi_union_pw_aff_drop_dims(band->mupa,
                                                        isl_dim_set, pos, n);
        if (!band->mupa)
                return isl_schedule_band_free(band);

        for (i = pos + n; i < band->n; ++i)
                band->coincident[i - n] = band->coincident[i];
        if (band->loop_type)
                for (i = pos + n; i < band->n; ++i)
                        band->loop_type[i - n] = band->loop_type[i];
        free(band->isolate_loop_type);
        band->isolate_loop_type = NULL;

        band->n -= n;

        return band;
}

/* Reset the user pointer on all identifiers of parameters and tuples
 * in "band".
 */
__isl_give isl_schedule_band *isl_schedule_band_reset_user(
        __isl_take isl_schedule_band *band)
{
        band = isl_schedule_band_cow(band);
        if (!band)
                return NULL;

        band->mupa = isl_multi_union_pw_aff_reset_user(band->mupa);
        band->ast_build_options =
                isl_union_set_reset_user(band->ast_build_options);
        if (!band->mupa || !band->ast_build_options)
                return isl_schedule_band_free(band);

        return band;
}

/* Align the parameters of "band" to those of "space".
 */
__isl_give isl_schedule_band *isl_schedule_band_align_params(
        __isl_take isl_schedule_band *band, __isl_take isl_space *space)
{
        band = isl_schedule_band_cow(band);
        if (!band || !space)
                goto error;

        band->mupa = isl_multi_union_pw_aff_align_params(band->mupa,
                                                isl_space_copy(space));
        band->ast_build_options =
                isl_union_set_align_params(band->ast_build_options, space);
        if (!band->mupa || !band->ast_build_options)
                return isl_schedule_band_free(band);

        return band;
error:
        isl_space_free(space);
        isl_schedule_band_free(band);
        return NULL;
}

/* Compute the pullback of "band" by the function represented by "upma".
 * In other words, plug in "upma" in the iteration domains of "band".
 */
__isl_give isl_schedule_band *isl_schedule_band_pullback_union_pw_multi_aff(
        __isl_take isl_schedule_band *band,
        __isl_take isl_union_pw_multi_aff *upma)
{
        band = isl_schedule_band_cow(band);
        if (!band || !upma)
                goto error;

        band->mupa =
                isl_multi_union_pw_aff_pullback_union_pw_multi_aff(band->mupa,
                                                                        upma);
        if (!band->mupa)
                return isl_schedule_band_free(band);

        return band;
error:
        isl_union_pw_multi_aff_free(upma);
        isl_schedule_band_free(band);
        return NULL;
}

/* Compute the gist of "band" with respect to "context".
 * In particular, compute the gist of the associated partial schedule.
 */
__isl_give isl_schedule_band *isl_schedule_band_gist(
        __isl_take isl_schedule_band *band, __isl_take isl_union_set *context)
{
        if (!band || !context)
                goto error;
        if (band->n == 0) {
                isl_union_set_free(context);
                return band;
        }
        band = isl_schedule_band_cow(band);
        if (!band)
                goto error;
        band->mupa = isl_multi_union_pw_aff_gist(band->mupa, context);
        if (!band->mupa)
                return isl_schedule_band_free(band);
        return band;
error:
        isl_union_set_free(context);
        isl_schedule_band_free(band);
        return NULL;
}