return NULL;
}
+__isl_give struct isl_upoly *isl_upoly_subs(__isl_take struct isl_upoly *up,
+ unsigned first, unsigned n, __isl_keep struct isl_upoly **subs)
+{
+ int i;
+ struct isl_upoly_rec *rec;
+ struct isl_upoly *base, *res;
+
+ if (!up)
+ return NULL;
+
+ if (isl_upoly_is_cst(up))
+ return up;
+
+ if (up->var < first)
+ return up;
+
+ rec = isl_upoly_as_rec(up);
+ if (!rec)
+ goto error;
+
+ isl_assert(up->ctx, rec->n >= 1, goto error);
+
+ if (up->var >= first + n)
+ base = isl_upoly_var_pow(up->ctx, up->var, 1);
+ else
+ base = isl_upoly_copy(subs[up->var - first]);
+
+ res = isl_upoly_subs(isl_upoly_copy(rec->p[rec->n - 1]), first, n, subs);
+ for (i = rec->n - 2; i >= 0; --i) {
+ struct isl_upoly *t;
+ t = isl_upoly_subs(isl_upoly_copy(rec->p[i]), first, n, subs);
+ res = isl_upoly_mul(res, isl_upoly_copy(base));
+ res = isl_upoly_sum(res, t);
+ }
+
+ isl_upoly_free(base);
+ isl_upoly_free(up);
+
+ return res;
+error:
+ isl_upoly_free(up);
+ return NULL;
+}
+
+__isl_give struct isl_upoly *isl_upoly_from_affine(isl_ctx *ctx, isl_int *f,
+ isl_int denom, unsigned len)
+{
+ int i;
+ struct isl_upoly *up;
+
+ isl_assert(ctx, len >= 1, return NULL);
+
+ up = isl_upoly_rat_cst(ctx, f[0], denom);
+ for (i = 0; i < len - 1; ++i) {
+ struct isl_upoly *t;
+ struct isl_upoly *c;
+
+ if (isl_int_is_zero(f[1 + i]))
+ continue;
+
+ c = isl_upoly_rat_cst(ctx, f[1 + i], denom);
+ t = isl_upoly_var_pow(ctx, i, 1);
+ t = isl_upoly_mul(c, t);
+ up = isl_upoly_sum(up, t);
+ }
+
+ return up;
+}
+
/* Remove common factor of non-constant terms and denominator.
*/
static void normalize_div(__isl_keep isl_qpolynomial *qp, int div)
ctx->normalize_gcd);
}
+/* Replace the integer division identified by "div" by the polynomial "s".
+ * The integer division is assumed not to appear in the definition
+ * of any other integer divisions.
+ */
+static __isl_give isl_qpolynomial *substitute_div(
+ __isl_take isl_qpolynomial *qp,
+ int div, __isl_take struct isl_upoly *s)
+{
+ int i;
+ int total;
+ int *reordering;
+
+ if (!qp || !s)
+ goto error;
+
+ qp = isl_qpolynomial_cow(qp);
+ if (!qp)
+ goto error;
+
+ total = isl_dim_total(qp->dim);
+ qp->upoly = isl_upoly_subs(qp->upoly, total + div, 1, &s);
+ if (!qp->upoly)
+ goto error;
+
+ reordering = isl_alloc_array(qp->dim->ctx, int, total + qp->div->n_row);
+ if (!reordering)
+ goto error;
+ for (i = 0; i < total + div; ++i)
+ reordering[i] = i;
+ for (i = total + div + 1; i < total + qp->div->n_row; ++i)
+ reordering[i] = i - 1;
+ qp->div = isl_mat_drop_rows(qp->div, div, 1);
+ qp->div = isl_mat_drop_cols(qp->div, 2 + total + div, 1);
+ qp->upoly = reorder(qp->upoly, reordering);
+ free(reordering);
+
+ if (!qp->upoly || !qp->div)
+ goto error;
+
+ isl_upoly_free(s);
+ return qp;
+error:
+ isl_qpolynomial_free(qp);
+ isl_upoly_free(s);
+ return NULL;
+}
+
+/* Replace all integer divisions [e/d] that turn out to not actually be integer
+ * divisions because d is equal to 1 by their definition, i.e., e.
+ */
+static __isl_give isl_qpolynomial *substitute_non_divs(
+ __isl_take isl_qpolynomial *qp)
+{
+ int i, j;
+ int total;
+ struct isl_upoly *s;
+
+ if (!qp)
+ return NULL;
+
+ total = isl_dim_total(qp->dim);
+ for (i = 0; qp && i < qp->div->n_row; ++i) {
+ if (!isl_int_is_one(qp->div->row[i][0]))
+ continue;
+ for (j = i + 1; j < qp->div->n_row; ++j) {
+ if (isl_int_is_zero(qp->div->row[j][2 + total + i]))
+ continue;
+ isl_seq_combine(qp->div->row[j] + 1,
+ qp->div->ctx->one, qp->div->row[j] + 1,
+ qp->div->row[j][2 + total + i],
+ qp->div->row[i] + 1, 1 + total + i);
+ isl_int_set_si(qp->div->row[j][2 + total + i], 0);
+ normalize_div(qp, j);
+ }
+ s = isl_upoly_from_affine(qp->dim->ctx, qp->div->row[i] + 1,
+ qp->div->row[i][0], qp->div->n_col - 1);
+ qp = substitute_div(qp, i, s);
+ --i;
+ }
+
+ return qp;
+}
+
+/* Reduce the coefficients of div "div" to lie in the interval [0, d-1],
+ * with d the denominator. When replacing the coefficient e of x by
+ * d * frac(e/d) = e - d * floor(e/d), we are subtracting d * floor(e/d) * x
+ * inside the division, so we need to add floor(e/d) * x outside.
+ * That is, we replace q by q' + floor(e/d) * x and we therefore need
+ * to adjust the coefficient of x in each later div that depends on the
+ * current div "div" and also in the affine expression "aff"
+ * (if it too depends on "div").
+ */
+static void reduce_div(__isl_keep isl_qpolynomial *qp, int div,
+ __isl_keep isl_vec *aff)
+{
+ int i, j;
+ isl_int v;
+ unsigned total = qp->div->n_col - qp->div->n_row - 2;
+
+ isl_int_init(v);
+ for (i = 0; i < 1 + total + div; ++i) {
+ if (isl_int_is_nonneg(qp->div->row[div][1 + i]) &&
+ isl_int_lt(qp->div->row[div][1 + i], qp->div->row[div][0]))
+ continue;
+ isl_int_fdiv_q(v, qp->div->row[div][1 + i], qp->div->row[div][0]);
+ isl_int_fdiv_r(qp->div->row[div][1 + i],
+ qp->div->row[div][1 + i], qp->div->row[div][0]);
+ if (!isl_int_is_zero(aff->el[1 + total + div]))
+ isl_int_addmul(aff->el[i], v, aff->el[1 + total + div]);
+ for (j = div + 1; j < qp->div->n_row; ++j) {
+ if (isl_int_is_zero(qp->div->row[j][2 + total + div]))
+ continue;
+ isl_int_addmul(qp->div->row[j][1 + i],
+ v, qp->div->row[j][2 + total + div]);
+ }
+ }
+ isl_int_clear(v);
+}
+
+/* Check if the last non-zero coefficient is bigger that half of the
+ * denominator. If so, we will invert the div to further reduce the number
+ * of distinct divs that may appear.
+ * If the last non-zero coefficient is exactly half the denominator,
+ * then we continue looking for earlier coefficients that are bigger
+ * than half the denominator.
+ */
+static int needs_invert(__isl_keep isl_mat *div, int row)
+{
+ int i;
+ int cmp;
+
+ for (i = div->n_col - 1; i >= 1; --i) {
+ if (isl_int_is_zero(div->row[row][i]))
+ continue;
+ isl_int_mul_ui(div->row[row][i], div->row[row][i], 2);
+ cmp = isl_int_cmp(div->row[row][i], div->row[row][0]);
+ isl_int_divexact_ui(div->row[row][i], div->row[row][i], 2);
+ if (cmp)
+ return cmp > 0;
+ if (i == 1)
+ return 1;
+ }
+
+ return 0;
+}
+
+/* Replace div "div" q = [e/d] by -[(-e+(d-1))/d].
+ * We only invert the coefficients of e (and the coefficient of q in
+ * later divs and in "aff"). After calling this function, the
+ * coefficients of e should be reduced again.
+ */
+static void invert_div(__isl_keep isl_qpolynomial *qp, int div,
+ __isl_keep isl_vec *aff)
+{
+ unsigned total = qp->div->n_col - qp->div->n_row - 2;
+
+ isl_seq_neg(qp->div->row[div] + 1,
+ qp->div->row[div] + 1, qp->div->n_col - 1);
+ isl_int_sub_ui(qp->div->row[div][1], qp->div->row[div][1], 1);
+ isl_int_add(qp->div->row[div][1],
+ qp->div->row[div][1], qp->div->row[div][0]);
+ if (!isl_int_is_zero(aff->el[1 + total + div]))
+ isl_int_neg(aff->el[1 + total + div], aff->el[1 + total + div]);
+ isl_mat_col_mul(qp->div, 2 + total + div,
+ qp->div->ctx->negone, 2 + total + div);
+}
+
+/* Assuming "qp" is a monomial, reduce all its divs to have coefficients
+ * in the interval [0, d-1], with d the denominator and such that the
+ * last non-zero coefficient that is not equal to d/2 is smaller than d/2.
+ *
+ * After the reduction, some divs may have become redundant or identical,
+ * so we call substitute_non_divs and sort_divs. If these functions
+ * eliminate divs of merge * two or more divs into one, the coefficients
+ * of the enclosing divs may have to be reduced again, so we call
+ * ourselves recursively if the number of divs decreases.
+ */
+static __isl_give isl_qpolynomial *reduce_divs(__isl_take isl_qpolynomial *qp)
+{
+ int i, j;
+ isl_vec *aff = NULL;
+ struct isl_upoly *s;
+ unsigned n_div;
+
+ if (!qp)
+ return NULL;
+
+ aff = isl_vec_alloc(qp->div->ctx, qp->div->n_col - 1);
+ aff = isl_vec_clr(aff);
+ if (!aff)
+ goto error;
+
+ isl_int_set_si(aff->el[1 + qp->upoly->var], 1);
+
+ for (i = 0; i < qp->div->n_row; ++i) {
+ normalize_div(qp, i);
+ reduce_div(qp, i, aff);
+ if (needs_invert(qp->div, i)) {
+ invert_div(qp, i, aff);
+ reduce_div(qp, i, aff);
+ }
+ }
+
+ s = isl_upoly_from_affine(qp->div->ctx, aff->el,
+ qp->div->ctx->one, aff->size);
+ qp->upoly = isl_upoly_subs(qp->upoly, qp->upoly->var, 1, &s);
+ isl_upoly_free(s);
+ if (!qp->upoly)
+ goto error;
+
+ isl_vec_free(aff);
+
+ n_div = qp->div->n_row;
+ qp = substitute_non_divs(qp);
+ qp = sort_divs(qp);
+ if (qp && qp->div->n_row < n_div)
+ return reduce_divs(qp);
+
+ return qp;
+error:
+ isl_qpolynomial_free(qp);
+ isl_vec_free(aff);
+ return NULL;
+}
+
+/* Assumes each div only depends on earlier divs.
+ */
__isl_give isl_qpolynomial *isl_qpolynomial_div_pow(__isl_take isl_div *div,
int power)
{
if (!qp)
goto error;
- for (i = 0; i < div->bmap->n_div; ++i) {
+ for (i = 0; i < div->bmap->n_div; ++i)
isl_seq_cpy(qp->div->row[i], div->bmap->div[i], qp->div->n_col);
- normalize_div(qp, i);
- }
for (i = 0; i < 1 + power; ++i) {
rec->p[i] = isl_upoly_zero(div->ctx);
isl_div_free(div);
- qp = sort_divs(qp);
+ qp = reduce_divs(qp);
return qp;
error:
return NULL;
}
-__isl_give struct isl_upoly *isl_upoly_subs(__isl_take struct isl_upoly *up,
- unsigned first, unsigned n, __isl_keep struct isl_upoly **subs)
-{
- int i;
- struct isl_upoly_rec *rec;
- struct isl_upoly *base, *res;
-
- if (!up)
- return NULL;
-
- if (isl_upoly_is_cst(up))
- return up;
-
- if (up->var < first)
- return up;
-
- rec = isl_upoly_as_rec(up);
- if (!rec)
- goto error;
-
- isl_assert(up->ctx, rec->n >= 1, goto error);
-
- if (up->var >= first + n)
- base = isl_upoly_var_pow(up->ctx, up->var, 1);
- else
- base = isl_upoly_copy(subs[up->var - first]);
-
- res = isl_upoly_subs(isl_upoly_copy(rec->p[rec->n - 1]), first, n, subs);
- for (i = rec->n - 2; i >= 0; --i) {
- struct isl_upoly *t;
- t = isl_upoly_subs(isl_upoly_copy(rec->p[i]), first, n, subs);
- res = isl_upoly_mul(res, isl_upoly_copy(base));
- res = isl_upoly_sum(res, t);
- }
-
- isl_upoly_free(base);
- isl_upoly_free(up);
-
- return res;
-error:
- isl_upoly_free(up);
- return NULL;
-}
-
-__isl_give struct isl_upoly *isl_upoly_from_affine(isl_ctx *ctx, isl_int *f,
- isl_int denom, unsigned len)
-{
- int i;
- struct isl_upoly *up;
-
- isl_assert(ctx, len >= 1, return NULL);
-
- up = isl_upoly_rat_cst(ctx, f[0], denom);
- for (i = 0; i < len - 1; ++i) {
- struct isl_upoly *t;
- struct isl_upoly *c;
-
- if (isl_int_is_zero(f[1 + i]))
- continue;
-
- c = isl_upoly_rat_cst(ctx, f[1 + i], denom);
- t = isl_upoly_var_pow(ctx, i, 1);
- t = isl_upoly_mul(c, t);
- up = isl_upoly_sum(up, t);
- }
-
- return up;
-}
-
-/* Replace the integer division identified by "div" by the polynomial "s".
- * The integer division is assumed not to appear in the definition
- * of any other integer divisions.
- */
-static __isl_give isl_qpolynomial *substitute_div(
- __isl_take isl_qpolynomial *qp,
- int div, __isl_take struct isl_upoly *s)
-{
- int i;
- int total;
- int *reordering;
-
- if (!qp || !s)
- goto error;
-
- qp = isl_qpolynomial_cow(qp);
- if (!qp)
- goto error;
-
- total = isl_dim_total(qp->dim);
- qp->upoly = isl_upoly_subs(qp->upoly, total + div, 1, &s);
- if (!qp->upoly)
- goto error;
-
- reordering = isl_alloc_array(qp->dim->ctx, int, total + qp->div->n_row);
- if (!reordering)
- goto error;
- for (i = 0; i < total + div; ++i)
- reordering[i] = i;
- for (i = total + div + 1; i < total + qp->div->n_row; ++i)
- reordering[i] = i - 1;
- qp->div = isl_mat_drop_rows(qp->div, div, 1);
- qp->div = isl_mat_drop_cols(qp->div, 2 + total + div, 1);
- qp->upoly = reorder(qp->upoly, reordering);
- free(reordering);
-
- if (!qp->upoly || !qp->div)
- goto error;
-
- isl_upoly_free(s);
- return qp;
-error:
- isl_qpolynomial_free(qp);
- isl_upoly_free(s);
- return NULL;
-}
-
-/* Replace all integer divisions [e/d] that turn out to not actually be integer
- * divisions because d is equal to 1 by their definition, i.e., e.
- */
-static __isl_give isl_qpolynomial *substitute_non_divs(
- __isl_take isl_qpolynomial *qp)
-{
- int i, j;
- int total;
- struct isl_upoly *s;
-
- if (!qp)
- return NULL;
-
- total = isl_dim_total(qp->dim);
- for (i = 0; qp && i < qp->div->n_row; ++i) {
- if (!isl_int_is_one(qp->div->row[i][0]))
- continue;
- for (j = i + 1; j < qp->div->n_row; ++j) {
- if (isl_int_is_zero(qp->div->row[j][2 + total + i]))
- continue;
- isl_seq_combine(qp->div->row[j] + 1,
- qp->div->ctx->one, qp->div->row[j] + 1,
- qp->div->row[j][2 + total + i],
- qp->div->row[i] + 1, 1 + total + i);
- isl_int_set_si(qp->div->row[j][2 + total + i], 0);
- normalize_div(qp, j);
- }
- s = isl_upoly_from_affine(qp->dim->ctx, qp->div->row[i] + 1,
- qp->div->row[i][0], qp->div->n_col - 1);
- qp = substitute_div(qp, i, s);
- --i;
- }
-
- return qp;
-}
-
__isl_give isl_qpolynomial *isl_qpolynomial_substitute_equalities(
__isl_take isl_qpolynomial *qp, __isl_take isl_basic_set *eq)
{
projects / platform / upstream / isl.git / commitdiff