blob: 5887403bd37f53eb33a75a471ea19f01f662d88f [file] [log] [blame]
/*
* Copyright 2010 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_map_private.h>
#include <isl_morph.h>
#include <isl/seq.h>
#include <isl_mat_private.h>
#include <isl_dim_private.h>
#include <isl_equalities.h>
__isl_give isl_morph *isl_morph_alloc(
__isl_take isl_basic_set *dom, __isl_take isl_basic_set *ran,
__isl_take isl_mat *map, __isl_take isl_mat *inv)
{
isl_morph *morph;
if (!dom || !ran || !map || !inv)
goto error;
morph = isl_alloc_type(dom->ctx, struct isl_morph);
if (!morph)
goto error;
morph->ref = 1;
morph->dom = dom;
morph->ran = ran;
morph->map = map;
morph->inv = inv;
return morph;
error:
isl_basic_set_free(dom);
isl_basic_set_free(ran);
isl_mat_free(map);
isl_mat_free(inv);
return NULL;
}
__isl_give isl_morph *isl_morph_copy(__isl_keep isl_morph *morph)
{
if (!morph)
return NULL;
morph->ref++;
return morph;
}
__isl_give isl_morph *isl_morph_dup(__isl_keep isl_morph *morph)
{
if (!morph)
return NULL;
return isl_morph_alloc(isl_basic_set_copy(morph->dom),
isl_basic_set_copy(morph->ran),
isl_mat_copy(morph->map), isl_mat_copy(morph->inv));
}
__isl_give isl_morph *isl_morph_cow(__isl_take isl_morph *morph)
{
if (!morph)
return NULL;
if (morph->ref == 1)
return morph;
morph->ref--;
return isl_morph_dup(morph);
}
void isl_morph_free(__isl_take isl_morph *morph)
{
if (!morph)
return;
if (--morph->ref > 0)
return;
isl_basic_set_free(morph->dom);
isl_basic_set_free(morph->ran);
isl_mat_free(morph->map);
isl_mat_free(morph->inv);
free(morph);
}
__isl_give isl_dim *isl_morph_get_ran_dim(__isl_keep isl_morph *morph)
{
if (!morph)
return NULL;
return isl_dim_copy(morph->ran->dim);
}
unsigned isl_morph_dom_dim(__isl_keep isl_morph *morph, enum isl_dim_type type)
{
if (!morph)
return 0;
return isl_basic_set_dim(morph->dom, type);
}
unsigned isl_morph_ran_dim(__isl_keep isl_morph *morph, enum isl_dim_type type)
{
if (!morph)
return 0;
return isl_basic_set_dim(morph->ran, type);
}
__isl_give isl_morph *isl_morph_remove_dom_dims(__isl_take isl_morph *morph,
enum isl_dim_type type, unsigned first, unsigned n)
{
unsigned dom_offset;
if (n == 0)
return morph;
morph = isl_morph_cow(morph);
if (!morph)
return NULL;
dom_offset = 1 + isl_dim_offset(morph->dom->dim, type);
morph->dom = isl_basic_set_remove_dims(morph->dom, type, first, n);
morph->map = isl_mat_drop_cols(morph->map, dom_offset + first, n);
morph->inv = isl_mat_drop_rows(morph->inv, dom_offset + first, n);
if (morph->dom && morph->ran && morph->map && morph->inv)
return morph;
isl_morph_free(morph);
return NULL;
}
__isl_give isl_morph *isl_morph_remove_ran_dims(__isl_take isl_morph *morph,
enum isl_dim_type type, unsigned first, unsigned n)
{
unsigned ran_offset;
if (n == 0)
return morph;
morph = isl_morph_cow(morph);
if (!morph)
return NULL;
ran_offset = 1 + isl_dim_offset(morph->ran->dim, type);
morph->ran = isl_basic_set_remove_dims(morph->ran, type, first, n);
morph->map = isl_mat_drop_rows(morph->map, ran_offset + first, n);
morph->inv = isl_mat_drop_cols(morph->inv, ran_offset + first, n);
if (morph->dom && morph->ran && morph->map && morph->inv)
return morph;
isl_morph_free(morph);
return NULL;
}
void isl_morph_dump(__isl_take isl_morph *morph, FILE *out)
{
if (!morph)
return;
isl_basic_set_print(morph->dom, out, 0, "", "", ISL_FORMAT_ISL);
isl_basic_set_print(morph->ran, out, 0, "", "", ISL_FORMAT_ISL);
isl_mat_print_internal(morph->map, out, 4);
isl_mat_print_internal(morph->inv, out, 4);
}
__isl_give isl_morph *isl_morph_identity(__isl_keep isl_basic_set *bset)
{
isl_mat *id;
isl_basic_set *universe;
unsigned total;
if (!bset)
return NULL;
total = isl_basic_set_total_dim(bset);
id = isl_mat_identity(bset->ctx, 1 + total);
universe = isl_basic_set_universe(isl_dim_copy(bset->dim));
return isl_morph_alloc(universe, isl_basic_set_copy(universe),
id, isl_mat_copy(id));
}
/* Create a(n identity) morphism between empty sets of the same dimension
* a "bset".
*/
__isl_give isl_morph *isl_morph_empty(__isl_keep isl_basic_set *bset)
{
isl_mat *id;
isl_basic_set *empty;
unsigned total;
if (!bset)
return NULL;
total = isl_basic_set_total_dim(bset);
id = isl_mat_identity(bset->ctx, 1 + total);
empty = isl_basic_set_empty(isl_dim_copy(bset->dim));
return isl_morph_alloc(empty, isl_basic_set_copy(empty),
id, isl_mat_copy(id));
}
/* Given a matrix that maps a (possibly) parametric domain to
* a parametric domain, add in rows that map the "nparam" parameters onto
* themselves.
*/
static __isl_give isl_mat *insert_parameter_rows(__isl_take isl_mat *mat,
unsigned nparam)
{
int i;
if (nparam == 0)
return mat;
if (!mat)
return NULL;
mat = isl_mat_insert_rows(mat, 1, nparam);
if (!mat)
return NULL;
for (i = 0; i < nparam; ++i) {
isl_seq_clr(mat->row[1 + i], mat->n_col);
isl_int_set(mat->row[1 + i][1 + i], mat->row[0][0]);
}
return mat;
}
/* Construct a basic set described by the "n" equalities of "bset" starting
* at "first".
*/
static __isl_give isl_basic_set *copy_equalities(__isl_keep isl_basic_set *bset,
unsigned first, unsigned n)
{
int i, k;
isl_basic_set *eq;
unsigned total;
isl_assert(bset->ctx, bset->n_div == 0, return NULL);
total = isl_basic_set_total_dim(bset);
eq = isl_basic_set_alloc_dim(isl_dim_copy(bset->dim), 0, n, 0);
if (!eq)
return NULL;
for (i = 0; i < n; ++i) {
k = isl_basic_set_alloc_equality(eq);
if (k < 0)
goto error;
isl_seq_cpy(eq->eq[k], bset->eq[first + k], 1 + total);
}
return eq;
error:
isl_basic_set_free(eq);
return NULL;
}
/* Given a basic set, exploit the equalties in the a basic set to construct
* a morphishm that maps the basic set to a lower-dimensional space.
* Specifically, the morphism reduces the number of dimensions of type "type".
*
* This function is a slight generalization of isl_mat_variable_compression
* in that it allows the input to be parametric and that it allows for the
* compression of either parameters or set variables.
*
* We first select the equalities of interest, that is those that involve
* variables of type "type" and no later variables.
* Denote those equalities as
*
* -C(p) + M x = 0
*
* where C(p) depends on the parameters if type == isl_dim_set and
* is a constant if type == isl_dim_param.
*
* First compute the (left) Hermite normal form of M,
*
* M [U1 U2] = M U = H = [H1 0]
* or
* M = H Q = [H1 0] [Q1]
* [Q2]
*
* with U, Q unimodular, Q = U^{-1} (and H lower triangular).
* Define the transformed variables as
*
* x = [U1 U2] [ x1' ] = [U1 U2] [Q1] x
* [ x2' ] [Q2]
*
* The equalities then become
*
* -C(p) + H1 x1' = 0 or x1' = H1^{-1} C(p) = C'(p)
*
* If the denominator of the constant term does not divide the
* the common denominator of the parametric terms, then every
* integer point is mapped to a non-integer point and then the original set has no
* integer solutions (since the x' are a unimodular transformation
* of the x). In this case, an empty morphism is returned.
* Otherwise, the transformation is given by
*
* x = U1 H1^{-1} C(p) + U2 x2'
*
* The inverse transformation is simply
*
* x2' = Q2 x
*
* Both matrices are extended to map the full original space to the full
* compressed space.
*/
__isl_give isl_morph *isl_basic_set_variable_compression(
__isl_keep isl_basic_set *bset, enum isl_dim_type type)
{
unsigned otype;
unsigned ntype;
unsigned orest;
unsigned nrest;
int f_eq, n_eq;
isl_dim *dim;
isl_mat *H, *U, *Q, *C = NULL, *H1, *U1, *U2;
isl_basic_set *dom, *ran;
if (!bset)
return NULL;
if (isl_basic_set_plain_is_empty(bset))
return isl_morph_empty(bset);
isl_assert(bset->ctx, bset->n_div == 0, return NULL);
otype = 1 + isl_dim_offset(bset->dim, type);
ntype = isl_basic_set_dim(bset, type);
orest = otype + ntype;
nrest = isl_basic_set_total_dim(bset) - (orest - 1);
for (f_eq = 0; f_eq < bset->n_eq; ++f_eq)
if (isl_seq_first_non_zero(bset->eq[f_eq] + orest, nrest) == -1)
break;
for (n_eq = 0; f_eq + n_eq < bset->n_eq; ++n_eq)
if (isl_seq_first_non_zero(bset->eq[f_eq + n_eq] + otype, ntype) == -1)
break;
if (n_eq == 0)
return isl_morph_identity(bset);
H = isl_mat_sub_alloc6(bset->ctx, bset->eq, f_eq, n_eq, otype, ntype);
H = isl_mat_left_hermite(H, 0, &U, &Q);
if (!H || !U || !Q)
goto error;
Q = isl_mat_drop_rows(Q, 0, n_eq);
Q = isl_mat_diagonal(isl_mat_identity(bset->ctx, otype), Q);
Q = isl_mat_diagonal(Q, isl_mat_identity(bset->ctx, nrest));
C = isl_mat_alloc(bset->ctx, 1 + n_eq, otype);
if (!C)
goto error;
isl_int_set_si(C->row[0][0], 1);
isl_seq_clr(C->row[0] + 1, otype - 1);
isl_mat_sub_neg(C->ctx, C->row + 1, bset->eq + f_eq, n_eq, 0, 0, otype);
H1 = isl_mat_sub_alloc(H, 0, H->n_row, 0, H->n_row);
H1 = isl_mat_lin_to_aff(H1);
C = isl_mat_inverse_product(H1, C);
if (!C)
goto error;
isl_mat_free(H);
if (!isl_int_is_one(C->row[0][0])) {
int i;
isl_int g;
isl_int_init(g);
for (i = 0; i < n_eq; ++i) {
isl_seq_gcd(C->row[1 + i] + 1, otype - 1, &g);
isl_int_gcd(g, g, C->row[0][0]);
if (!isl_int_is_divisible_by(C->row[1 + i][0], g))
break;
}
isl_int_clear(g);
if (i < n_eq) {
isl_mat_free(C);
isl_mat_free(U);
isl_mat_free(Q);
return isl_morph_empty(bset);
}
C = isl_mat_normalize(C);
}
U1 = isl_mat_sub_alloc(U, 0, U->n_row, 0, n_eq);
U1 = isl_mat_lin_to_aff(U1);
U2 = isl_mat_sub_alloc(U, 0, U->n_row, n_eq, U->n_row - n_eq);
U2 = isl_mat_lin_to_aff(U2);
isl_mat_free(U);
C = isl_mat_product(U1, C);
C = isl_mat_aff_direct_sum(C, U2);
C = insert_parameter_rows(C, otype - 1);
C = isl_mat_diagonal(C, isl_mat_identity(bset->ctx, nrest));
dim = isl_dim_copy(bset->dim);
dim = isl_dim_drop(dim, type, 0, ntype);
dim = isl_dim_add(dim, type, ntype - n_eq);
ran = isl_basic_set_universe(dim);
dom = copy_equalities(bset, f_eq, n_eq);
return isl_morph_alloc(dom, ran, Q, C);
error:
isl_mat_free(C);
isl_mat_free(H);
isl_mat_free(U);
isl_mat_free(Q);
return NULL;
}
/* Construct a parameter compression for "bset".
* We basically just call isl_mat_parameter_compression with the right input
* and then extend the resulting matrix to include the variables.
*
* Let the equalities be given as
*
* B(p) + A x = 0
*
* and let [H 0] be the Hermite Normal Form of A, then
*
* H^-1 B(p)
*
* needs to be integer, so we impose that each row is divisible by
* the denominator.
*/
__isl_give isl_morph *isl_basic_set_parameter_compression(
__isl_keep isl_basic_set *bset)
{
unsigned nparam;
unsigned nvar;
int n_eq;
isl_mat *H, *B;
isl_vec *d;
isl_mat *map, *inv;
isl_basic_set *dom, *ran;
if (!bset)
return NULL;
if (isl_basic_set_plain_is_empty(bset))
return isl_morph_empty(bset);
if (bset->n_eq == 0)
return isl_morph_identity(bset);
isl_assert(bset->ctx, bset->n_div == 0, return NULL);
n_eq = bset->n_eq;
nparam = isl_basic_set_dim(bset, isl_dim_param);
nvar = isl_basic_set_dim(bset, isl_dim_set);
isl_assert(bset->ctx, n_eq <= nvar, return NULL);
d = isl_vec_alloc(bset->ctx, n_eq);
B = isl_mat_sub_alloc6(bset->ctx, bset->eq, 0, n_eq, 0, 1 + nparam);
H = isl_mat_sub_alloc6(bset->ctx, bset->eq, 0, n_eq, 1 + nparam, nvar);
H = isl_mat_left_hermite(H, 0, NULL, NULL);
H = isl_mat_drop_cols(H, n_eq, nvar - n_eq);
H = isl_mat_lin_to_aff(H);
H = isl_mat_right_inverse(H);
if (!H || !d)
goto error;
isl_seq_set(d->el, H->row[0][0], d->size);
H = isl_mat_drop_rows(H, 0, 1);
H = isl_mat_drop_cols(H, 0, 1);
B = isl_mat_product(H, B);
inv = isl_mat_parameter_compression(B, d);
inv = isl_mat_diagonal(inv, isl_mat_identity(bset->ctx, nvar));
map = isl_mat_right_inverse(isl_mat_copy(inv));
dom = isl_basic_set_universe(isl_dim_copy(bset->dim));
ran = isl_basic_set_universe(isl_dim_copy(bset->dim));
return isl_morph_alloc(dom, ran, map, inv);
error:
isl_mat_free(H);
isl_mat_free(B);
isl_vec_free(d);
return NULL;
}
/* Add stride constraints to "bset" based on the inverse mapping
* that was plugged in. In particular, if morph maps x' to x,
* the the constraints of the original input
*
* A x' + b >= 0
*
* have been rewritten to
*
* A inv x + b >= 0
*
* However, this substitution may loose information on the integrality of x',
* so we need to impose that
*
* inv x
*
* is integral. If inv = B/d, this means that we need to impose that
*
* B x = 0 mod d
*
* or
*
* exists alpha in Z^m: B x = d alpha
*
*/
static __isl_give isl_basic_set *add_strides(__isl_take isl_basic_set *bset,
__isl_keep isl_morph *morph)
{
int i, div, k;
isl_int gcd;
if (isl_int_is_one(morph->inv->row[0][0]))
return bset;
isl_int_init(gcd);
for (i = 0; 1 + i < morph->inv->n_row; ++i) {
isl_seq_gcd(morph->inv->row[1 + i], morph->inv->n_col, &gcd);
if (isl_int_is_divisible_by(gcd, morph->inv->row[0][0]))
continue;
div = isl_basic_set_alloc_div(bset);
if (div < 0)
goto error;
k = isl_basic_set_alloc_equality(bset);
if (k < 0)
goto error;
isl_seq_cpy(bset->eq[k], morph->inv->row[1 + i],
morph->inv->n_col);
isl_seq_clr(bset->eq[k] + morph->inv->n_col, bset->n_div);
isl_int_set(bset->eq[k][morph->inv->n_col + div],
morph->inv->row[0][0]);
}
isl_int_clear(gcd);
return bset;
error:
isl_int_clear(gcd);
isl_basic_set_free(bset);
return NULL;
}
/* Apply the morphism to the basic set.
* We basically just compute the preimage of "bset" under the inverse mapping
* in morph, add in stride constraints and intersect with the range
* of the morphism.
*/
__isl_give isl_basic_set *isl_morph_basic_set(__isl_take isl_morph *morph,
__isl_take isl_basic_set *bset)
{
isl_basic_set *res = NULL;
isl_mat *mat = NULL;
int i, k;
int max_stride;
if (!morph || !bset)
goto error;
isl_assert(bset->ctx, isl_dim_equal(bset->dim, morph->dom->dim),
goto error);
max_stride = morph->inv->n_row - 1;
if (isl_int_is_one(morph->inv->row[0][0]))
max_stride = 0;
res = isl_basic_set_alloc_dim(isl_dim_copy(morph->ran->dim),
bset->n_div + max_stride, bset->n_eq + max_stride, bset->n_ineq);
for (i = 0; i < bset->n_div; ++i)
if (isl_basic_set_alloc_div(res) < 0)
goto error;
mat = isl_mat_sub_alloc6(bset->ctx, bset->eq, 0, bset->n_eq,
0, morph->inv->n_row);
mat = isl_mat_product(mat, isl_mat_copy(morph->inv));
if (!mat)
goto error;
for (i = 0; i < bset->n_eq; ++i) {
k = isl_basic_set_alloc_equality(res);
if (k < 0)
goto error;
isl_seq_cpy(res->eq[k], mat->row[i], mat->n_col);
isl_seq_scale(res->eq[k] + mat->n_col, bset->eq[i] + mat->n_col,
morph->inv->row[0][0], bset->n_div);
}
isl_mat_free(mat);
mat = isl_mat_sub_alloc6(bset->ctx, bset->ineq, 0, bset->n_ineq,
0, morph->inv->n_row);
mat = isl_mat_product(mat, isl_mat_copy(morph->inv));
if (!mat)
goto error;
for (i = 0; i < bset->n_ineq; ++i) {
k = isl_basic_set_alloc_inequality(res);
if (k < 0)
goto error;
isl_seq_cpy(res->ineq[k], mat->row[i], mat->n_col);
isl_seq_scale(res->ineq[k] + mat->n_col,
bset->ineq[i] + mat->n_col,
morph->inv->row[0][0], bset->n_div);
}
isl_mat_free(mat);
mat = isl_mat_sub_alloc6(bset->ctx, bset->div, 0, bset->n_div,
1, morph->inv->n_row);
mat = isl_mat_product(mat, isl_mat_copy(morph->inv));
if (!mat)
goto error;
for (i = 0; i < bset->n_div; ++i) {
isl_int_mul(res->div[i][0],
morph->inv->row[0][0], bset->div[i][0]);
isl_seq_cpy(res->div[i] + 1, mat->row[i], mat->n_col);
isl_seq_scale(res->div[i] + 1 + mat->n_col,
bset->div[i] + 1 + mat->n_col,
morph->inv->row[0][0], bset->n_div);
}
isl_mat_free(mat);
res = add_strides(res, morph);
if (isl_basic_set_is_rational(bset))
res = isl_basic_set_set_rational(res);
res = isl_basic_set_simplify(res);
res = isl_basic_set_finalize(res);
res = isl_basic_set_intersect(res, isl_basic_set_copy(morph->ran));
isl_morph_free(morph);
isl_basic_set_free(bset);
return res;
error:
isl_mat_free(mat);
isl_morph_free(morph);
isl_basic_set_free(bset);
isl_basic_set_free(res);
return NULL;
}
/* Apply the morphism to the set.
*/
__isl_give isl_set *isl_morph_set(__isl_take isl_morph *morph,
__isl_take isl_set *set)
{
int i;
if (!morph || !set)
goto error;
isl_assert(set->ctx, isl_dim_equal(set->dim, morph->dom->dim), goto error);
set = isl_set_cow(set);
if (!set)
goto error;
isl_dim_free(set->dim);
set->dim = isl_dim_copy(morph->ran->dim);
if (!set->dim)
goto error;
for (i = 0; i < set->n; ++i) {
set->p[i] = isl_morph_basic_set(isl_morph_copy(morph), set->p[i]);
if (!set->p[i])
goto error;
}
isl_morph_free(morph);
ISL_F_CLR(set, ISL_SET_NORMALIZED);
return set;
error:
isl_set_free(set);
isl_morph_free(morph);
return NULL;
}
/* Construct a morphism that first does morph2 and then morph1.
*/
__isl_give isl_morph *isl_morph_compose(__isl_take isl_morph *morph1,
__isl_take isl_morph *morph2)
{
isl_mat *map, *inv;
isl_basic_set *dom, *ran;
if (!morph1 || !morph2)
goto error;
map = isl_mat_product(isl_mat_copy(morph1->map), isl_mat_copy(morph2->map));
inv = isl_mat_product(isl_mat_copy(morph2->inv), isl_mat_copy(morph1->inv));
dom = isl_morph_basic_set(isl_morph_inverse(isl_morph_copy(morph2)),
isl_basic_set_copy(morph1->dom));
dom = isl_basic_set_intersect(dom, isl_basic_set_copy(morph2->dom));
ran = isl_morph_basic_set(isl_morph_copy(morph1),
isl_basic_set_copy(morph2->ran));
ran = isl_basic_set_intersect(ran, isl_basic_set_copy(morph1->ran));
isl_morph_free(morph1);
isl_morph_free(morph2);
return isl_morph_alloc(dom, ran, map, inv);
error:
isl_morph_free(morph1);
isl_morph_free(morph2);
return NULL;
}
__isl_give isl_morph *isl_morph_inverse(__isl_take isl_morph *morph)
{
isl_basic_set *bset;
isl_mat *mat;
morph = isl_morph_cow(morph);
if (!morph)
return NULL;
bset = morph->dom;
morph->dom = morph->ran;
morph->ran = bset;
mat = morph->map;
morph->map = morph->inv;
morph->inv = mat;
return morph;
}
__isl_give isl_morph *isl_basic_set_full_compression(
__isl_keep isl_basic_set *bset)
{
isl_morph *morph, *morph2;
bset = isl_basic_set_copy(bset);
morph = isl_basic_set_variable_compression(bset, isl_dim_param);
bset = isl_morph_basic_set(isl_morph_copy(morph), bset);
morph2 = isl_basic_set_parameter_compression(bset);
bset = isl_morph_basic_set(isl_morph_copy(morph2), bset);
morph = isl_morph_compose(morph2, morph);
morph2 = isl_basic_set_variable_compression(bset, isl_dim_set);
isl_basic_set_free(bset);
morph = isl_morph_compose(morph2, morph);
return morph;
}
__isl_give isl_vec *isl_morph_vec(__isl_take isl_morph *morph,
__isl_take isl_vec *vec)
{
if (!morph)
goto error;
vec = isl_mat_vec_product(isl_mat_copy(morph->map), vec);
isl_morph_free(morph);
return vec;
error:
isl_morph_free(morph);
isl_vec_free(vec);
return NULL;
}