Ejemplo n.º 1
0
/* Check whether the polynomial "poly" has sign "sign" over "bset",
 * i.e., if sign == 1, check that the lower bound on the polynomial
 * is non-negative and if sign == -1, check that the upper bound on
 * the polynomial is non-positive.
 */
static int has_sign(__isl_keep isl_basic_set *bset,
	__isl_keep isl_qpolynomial *poly, int sign, int *signs)
{
	struct range_data data_m;
	unsigned nparam;
	isl_space *dim;
	isl_val *opt;
	int r;
	enum isl_fold type;

	nparam = isl_basic_set_dim(bset, isl_dim_param);

	bset = isl_basic_set_copy(bset);
	poly = isl_qpolynomial_copy(poly);

	bset = isl_basic_set_move_dims(bset, isl_dim_set, 0,
					isl_dim_param, 0, nparam);
	poly = isl_qpolynomial_move_dims(poly, isl_dim_in, 0,
					isl_dim_param, 0, nparam);

	dim = isl_qpolynomial_get_space(poly);
	dim = isl_space_params(dim);
	dim = isl_space_from_domain(dim);
	dim = isl_space_add_dims(dim, isl_dim_out, 1);

	data_m.test_monotonicity = 0;
	data_m.signs = signs;
	data_m.sign = -sign;
	type = data_m.sign < 0 ? isl_fold_min : isl_fold_max;
	data_m.pwf = isl_pw_qpolynomial_fold_zero(dim, type);
	data_m.tight = 0;
	data_m.pwf_tight = NULL;

	if (propagate_on_domain(bset, poly, &data_m) < 0)
		goto error;

	if (sign > 0)
		opt = isl_pw_qpolynomial_fold_min(data_m.pwf);
	else
		opt = isl_pw_qpolynomial_fold_max(data_m.pwf);

	if (!opt)
		r = -1;
	else if (isl_val_is_nan(opt) ||
		 isl_val_is_infty(opt) ||
		 isl_val_is_neginfty(opt))
		r = 0;
	else
		r = sign * isl_val_sgn(opt) >= 0;

	isl_val_free(opt);

	return r;
error:
	isl_pw_qpolynomial_fold_free(data_m.pwf);
	return -1;
}
Ejemplo n.º 2
0
enum lp_result isl_constraints_opt(Matrix *C, Value *obj, Value denom,
				    enum lp_dir dir, Value *opt)
{
	int i;
	isl_ctx *ctx = isl_ctx_alloc();
	isl_space *dim;
	isl_local_space *ls;
	isl_mat *eq, *ineq;
	isl_basic_set *bset;
	isl_aff *aff;
	isl_val *v;
	enum isl_lp_result res;
	int max = dir == lp_max;

	eq = extract_equalities(ctx, C);
	ineq = extract_inequalities(ctx, C);
	dim = isl_space_set_alloc(ctx, 0, C->NbColumns - 2);
	ls = isl_local_space_from_space(isl_space_copy(dim));
	bset = isl_basic_set_from_constraint_matrices(dim, eq, ineq,
			isl_dim_set, isl_dim_div, isl_dim_param, isl_dim_cst);
	aff = isl_aff_zero_on_domain(ls);
	for (i = 0; i < C->NbColumns - 2; ++i) {
		v = isl_val_int_from_gmp(ctx, obj[i]);
		aff = isl_aff_set_coefficient_val(aff, isl_dim_in, i, v);
	}
	v = isl_val_int_from_gmp(ctx, obj[C->NbColumns - 2]);
	aff = isl_aff_set_constant_val(aff, v);
	v = isl_val_int_from_gmp(ctx, denom);
	aff = isl_aff_scale_down_val(aff, v);

	if (max)
		v = isl_val_floor(isl_basic_set_max_lp_val(bset, aff));
	else
		v = isl_val_ceil(isl_basic_set_min_lp_val(bset, aff));
	if (!v)
		res = isl_lp_error;
	else if (isl_val_is_nan(v))
		res = isl_lp_empty;
	else if (!isl_val_is_rat(v))
		res = isl_lp_unbounded;
	else {
		res = isl_lp_ok;
		isl_val_get_num_gmp(v, *opt);
	}

	isl_val_free(v);
	isl_aff_free(aff);
	isl_basic_set_free(bset);
	isl_ctx_free(ctx);

	return isl_lp_result2lp_result(res);
}
Ejemplo n.º 3
0
enum order_sign isl_polyhedron_affine_sign(Polyhedron *D, Matrix *T,
					    struct barvinok_options *options)
{
	int i;
	isl_ctx *ctx = isl_ctx_alloc();
	isl_space *dim;
	isl_local_space *ls;
	isl_aff *aff;
	isl_basic_set *bset;
	isl_val *min, *max = NULL;
	isl_val *v;
	enum order_sign sign = order_undefined;

	assert(D->Dimension == T->NbColumns - 1);

	dim = isl_space_set_alloc(ctx, 0, D->Dimension);
	ls = isl_local_space_from_space(isl_space_copy(dim));
	bset = isl_basic_set_new_from_polylib(D, dim);
	aff = isl_aff_zero_on_domain(ls);
	for (i = 0; i < D->Dimension; ++i) {
		v = isl_val_int_from_gmp(ctx, T->p[0][i]);
		aff = isl_aff_set_coefficient_val(aff, isl_dim_in, i, v);
	}
	v = isl_val_int_from_gmp(ctx, T->p[0][D->Dimension]);
	aff = isl_aff_set_constant_val(aff, v);
	v = isl_val_int_from_gmp(ctx, T->p[1][D->Dimension]);
	aff = isl_aff_scale_down_val(aff, v);

	min = isl_basic_set_min_lp_val(bset, aff);
	min = isl_val_ceil(min);
	assert(min);

	if (isl_val_is_nan(min))
		sign = order_undefined;
	else if (isl_val_is_pos(min))
		sign = order_gt;
	else {
		max = isl_basic_set_max_lp_val(bset, aff);
		max = isl_val_floor(max);
		assert(max);

		if (isl_val_is_neg(max))
			sign = order_lt;
		else if (isl_val_is_zero(min) && isl_val_is_zero(max))
			sign = order_eq;
		else if (isl_val_is_zero(min))
			sign = order_ge;
		else if (isl_val_is_zero(max))
			sign = order_le;
		else
			sign = order_unknown;
	}

	isl_basic_set_free(bset);
	isl_aff_free(aff);
	isl_val_free(min);
	isl_val_free(max);
	isl_ctx_free(ctx);

	return sign;
}