1 files changed, 491 insertions, 0 deletions
diff --git a/polly/lib/External/isl/isl_range.c b/polly/lib/External/isl/isl_range.c
new file mode 100644
index 00000000000..5599582cb83
--- /dev/null
+++ b/polly/lib/External/isl/isl_range.c
@@ -0,0 +1,491 @@
+#include <isl_ctx_private.h>
+#include <isl_constraint_private.h>
+#include <isl/set.h>
+#include <isl_polynomial_private.h>
+#include <isl_morph.h>
+#include <isl_range.h>
+
+struct range_data {
+	struct isl_bound	*bound;
+	int 		    	*signs;
+	int			sign;
+	int			test_monotonicity;
+	int		    	monotonicity;
+	int			tight;
+	isl_qpolynomial	    	*poly;
+	isl_pw_qpolynomial_fold *pwf;
+	isl_pw_qpolynomial_fold *pwf_tight;
+};
+
+static int propagate_on_domain(__isl_take isl_basic_set *bset,
+	__isl_take isl_qpolynomial *poly, struct range_data *data);
+
+/* 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 nvar;
+	unsigned nparam;
+	isl_space *dim;
+	isl_val *opt;
+	int r;
+	enum isl_fold type;
+
+	nparam = isl_basic_set_dim(bset, isl_dim_param);
+	nvar = isl_basic_set_dim(bset, isl_dim_set);
+
+	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;
+}
+
+/* Return  1 if poly is monotonically increasing in the last set variable,
+ *        -1 if poly is monotonically decreasing in the last set variable,
+ *	   0 if no conclusion,
+ *	  -2 on error.
+ *
+ * We simply check the sign of p(x+1)-p(x)
+ */
+static int monotonicity(__isl_keep isl_basic_set *bset,
+	__isl_keep isl_qpolynomial *poly, struct range_data *data)
+{
+	isl_ctx *ctx;
+	isl_space *dim;
+	isl_qpolynomial *sub = NULL;
+	isl_qpolynomial *diff = NULL;
+	int result = 0;
+	int s;
+	unsigned nvar;
+
+	ctx = isl_qpolynomial_get_ctx(poly);
+	dim = isl_qpolynomial_get_domain_space(poly);
+
+	nvar = isl_basic_set_dim(bset, isl_dim_set);
+
+	sub = isl_qpolynomial_var_on_domain(isl_space_copy(dim), isl_dim_set, nvar - 1);
+	sub = isl_qpolynomial_add(sub,
+		isl_qpolynomial_rat_cst_on_domain(dim, ctx->one, ctx->one));
+
+	diff = isl_qpolynomial_substitute(isl_qpolynomial_copy(poly),
+			isl_dim_in, nvar - 1, 1, &sub);
+	diff = isl_qpolynomial_sub(diff, isl_qpolynomial_copy(poly));
+
+	s = has_sign(bset, diff, 1, data->signs);
+	if (s < 0)
+		goto error;
+	if (s)
+		result = 1;
+	else {
+		s = has_sign(bset, diff, -1, data->signs);
+		if (s < 0)
+			goto error;
+		if (s)
+			result = -1;
+	}
+
+	isl_qpolynomial_free(diff);
+	isl_qpolynomial_free(sub);
+
+	return result;
+error:
+	isl_qpolynomial_free(diff);
+	isl_qpolynomial_free(sub);
+	return -2;
+}
+
+static __isl_give isl_qpolynomial *bound2poly(__isl_take isl_constraint *bound,
+	__isl_take isl_space *dim, unsigned pos, int sign)
+{
+	if (!bound) {
+		if (sign > 0)
+			return isl_qpolynomial_infty_on_domain(dim);
+		else
+			return isl_qpolynomial_neginfty_on_domain(dim);
+	}
+	isl_space_free(dim);
+	return isl_qpolynomial_from_constraint(bound, isl_dim_set, pos);
+}
+
+static int bound_is_integer(__isl_take isl_constraint *bound, unsigned pos)
+{
+	isl_int c;
+	int is_int;
+
+	if (!bound)
+		return 1;
+
+	isl_int_init(c);
+	isl_constraint_get_coefficient(bound, isl_dim_set, pos, &c);
+	is_int = isl_int_is_one(c) || isl_int_is_negone(c);
+	isl_int_clear(c);
+
+	return is_int;
+}
+
+struct isl_fixed_sign_data {
+	int		*signs;
+	int		sign;
+	isl_qpolynomial	*poly;
+};
+
+/* Add term "term" to data->poly if it has sign data->sign.
+ * The sign is determined based on the signs of the parameters
+ * and variables in data->signs.  The integer divisions, if
+ * any, are assumed to be non-negative.
+ */
+static int collect_fixed_sign_terms(__isl_take isl_term *term, void *user)
+{
+	struct isl_fixed_sign_data *data = (struct isl_fixed_sign_data *)user;
+	isl_int n;
+	int i;
+	int sign;
+	unsigned nparam;
+	unsigned nvar;
+
+	if (!term)
+		return -1;
+
+	nparam = isl_term_dim(term, isl_dim_param);
+	nvar = isl_term_dim(term, isl_dim_set);
+
+	isl_int_init(n);
+
+	isl_term_get_num(term, &n);
+
+	sign = isl_int_sgn(n);
+	for (i = 0; i < nparam; ++i) {
+		if (data->signs[i] > 0)
+			continue;
+		if (isl_term_get_exp(term, isl_dim_param, i) % 2)
+			sign = -sign;
+	}
+	for (i = 0; i < nvar; ++i) {
+		if (data->signs[nparam + i] > 0)
+			continue;
+		if (isl_term_get_exp(term, isl_dim_set, i) % 2)
+			sign = -sign;
+	}
+
+	if (sign == data->sign) {
+		isl_qpolynomial *t = isl_qpolynomial_from_term(term);
+
+		data->poly = isl_qpolynomial_add(data->poly, t);
+	} else
+		isl_term_free(term);
+
+	isl_int_clear(n);
+
+	return 0;
+}
+
+/* Construct and return a polynomial that consists of the terms
+ * in "poly" that have sign "sign".  The integer divisions, if
+ * any, are assumed to be non-negative.
+ */
+__isl_give isl_qpolynomial *isl_qpolynomial_terms_of_sign(
+	__isl_keep isl_qpolynomial *poly, int *signs, int sign)
+{
+	isl_space *space;
+	struct isl_fixed_sign_data data = { signs, sign };
+
+	space = isl_qpolynomial_get_domain_space(poly);
+	data.poly = isl_qpolynomial_zero_on_domain(space);
+
+	if (isl_qpolynomial_foreach_term(poly, collect_fixed_sign_terms, &data) < 0)
+		goto error;
+
+	return data.poly;
+error:
+	isl_qpolynomial_free(data.poly);
+	return NULL;
+}
+
+/* Helper function to add a guarded polynomial to either pwf_tight or pwf,
+ * depending on whether the result has been determined to be tight.
+ */
+static int add_guarded_poly(__isl_take isl_basic_set *bset,
+	__isl_take isl_qpolynomial *poly, struct range_data *data)
+{
+	enum isl_fold type = data->sign < 0 ? isl_fold_min : isl_fold_max;
+	isl_set *set;
+	isl_qpolynomial_fold *fold;
+	isl_pw_qpolynomial_fold *pwf;
+
+	bset = isl_basic_set_params(bset);
+	poly = isl_qpolynomial_project_domain_on_params(poly);
+
+	fold = isl_qpolynomial_fold_alloc(type, poly);
+	set = isl_set_from_basic_set(bset);
+	pwf = isl_pw_qpolynomial_fold_alloc(type, set, fold);
+	if (data->tight)
+		data->pwf_tight = isl_pw_qpolynomial_fold_fold(
+						data->pwf_tight, pwf);
+	else
+		data->pwf = isl_pw_qpolynomial_fold_fold(data->pwf, pwf);
+
+	return 0;
+}
+
+/* Given a lower and upper bound on the final variable and constraints
+ * on the remaining variables where these bounds are active,
+ * eliminate the variable from data->poly based on these bounds.
+ * If the polynomial has been determined to be monotonic
+ * in the variable, then simply plug in the appropriate bound.
+ * If the current polynomial is tight and if this bound is integer,
+ * then the result is still tight.  In all other cases, the results
+ * may not be tight.
+ * Otherwise, plug in the largest bound (in absolute value) in
+ * the positive terms (if an upper bound is wanted) or the negative terms
+ * (if a lower bounded is wanted) and the other bound in the other terms.
+ *
+ * If all variables have been eliminated, then record the result.
+ * Ohterwise, recurse on the next variable.
+ */
+static int propagate_on_bound_pair(__isl_take isl_constraint *lower,
+	__isl_take isl_constraint *upper, __isl_take isl_basic_set *bset,
+	void *user)
+{
+	struct range_data *data = (struct range_data *)user;
+	int save_tight = data->tight;
+	isl_qpolynomial *poly;
+	int r;
+	unsigned nvar;
+
+	nvar = isl_basic_set_dim(bset, isl_dim_set);
+
+	if (data->monotonicity) {
+		isl_qpolynomial *sub;
+		isl_space *dim = isl_qpolynomial_get_domain_space(data->poly);
+		if (data->monotonicity * data->sign > 0) {
+			if (data->tight)
+				data->tight = bound_is_integer(upper, nvar);
+			sub = bound2poly(upper, dim, nvar, 1);
+			isl_constraint_free(lower);
+		} else {
+			if (data->tight)
+				data->tight = bound_is_integer(lower, nvar);
+			sub = bound2poly(lower, dim, nvar, -1);
+			isl_constraint_free(upper);
+		}
+		poly = isl_qpolynomial_copy(data->poly);
+		poly = isl_qpolynomial_substitute(poly, isl_dim_in, nvar, 1, &sub);
+		poly = isl_qpolynomial_drop_dims(poly, isl_dim_in, nvar, 1);
+
+		isl_qpolynomial_free(sub);
+	} else {
+		isl_qpolynomial *l, *u;
+		isl_qpolynomial *pos, *neg;
+		isl_space *dim = isl_qpolynomial_get_domain_space(data->poly);
+		unsigned nparam = isl_basic_set_dim(bset, isl_dim_param);
+		int sign = data->sign * data->signs[nparam + nvar];
+
+		data->tight = 0;
+
+		u = bound2poly(upper, isl_space_copy(dim), nvar, 1);
+		l = bound2poly(lower, dim, nvar, -1);
+
+		pos = isl_qpolynomial_terms_of_sign(data->poly, data->signs, sign);
+		neg = isl_qpolynomial_terms_of_sign(data->poly, data->signs, -sign);
+
+		pos = isl_qpolynomial_substitute(pos, isl_dim_in, nvar, 1, &u);
+		neg = isl_qpolynomial_substitute(neg, isl_dim_in, nvar, 1, &l);
+
+		poly = isl_qpolynomial_add(pos, neg);
+		poly = isl_qpolynomial_drop_dims(poly, isl_dim_in, nvar, 1);
+
+		isl_qpolynomial_free(u);
+		isl_qpolynomial_free(l);
+	}
+
+	if (isl_basic_set_dim(bset, isl_dim_set) == 0)
+		r = add_guarded_poly(bset, poly, data);
+	else
+		r = propagate_on_domain(bset, poly, data);
+
+	data->tight = save_tight;
+
+	return r;
+}
+
+/* Recursively perform range propagation on the polynomial "poly"
+ * defined over the basic set "bset" and collect the results in "data".
+ */
+static int propagate_on_domain(__isl_take isl_basic_set *bset,
+	__isl_take isl_qpolynomial *poly, struct range_data *data)
+{
+	isl_ctx *ctx;
+	isl_qpolynomial *save_poly = data->poly;
+	int save_monotonicity = data->monotonicity;
+	unsigned d;
+
+	if (!bset || !poly)
+		goto error;
+
+	ctx = isl_basic_set_get_ctx(bset);
+	d = isl_basic_set_dim(bset, isl_dim_set);
+	isl_assert(ctx, d >= 1, goto error);
+
+	if (isl_qpolynomial_is_cst(poly, NULL, NULL)) {
+		bset = isl_basic_set_project_out(bset, isl_dim_set, 0, d);
+		poly = isl_qpolynomial_drop_dims(poly, isl_dim_in, 0, d);
+		return add_guarded_poly(bset, poly, data);
+	}
+
+	if (data->test_monotonicity)
+		data->monotonicity = monotonicity(bset, poly, data);
+	else
+		data->monotonicity = 0;
+	if (data->monotonicity < -1)
+		goto error;
+
+	data->poly = poly;
+	if (isl_basic_set_foreach_bound_pair(bset, isl_dim_set, d - 1,
+					    &propagate_on_bound_pair, data) < 0)
+		goto error;
+
+	isl_basic_set_free(bset);
+	isl_qpolynomial_free(poly);
+	data->monotonicity = save_monotonicity;
+	data->poly = save_poly;
+
+	return 0;
+error:
+	isl_basic_set_free(bset);
+	isl_qpolynomial_free(poly);
+	data->monotonicity = save_monotonicity;
+	data->poly = save_poly;
+	return -1;
+}
+
+static int basic_guarded_poly_bound(__isl_take isl_basic_set *bset, void *user)
+{
+	struct range_data *data = (struct range_data *)user;
+	isl_ctx *ctx;
+	unsigned nparam = isl_basic_set_dim(bset, isl_dim_param);
+	unsigned dim = isl_basic_set_dim(bset, isl_dim_set);
+	int r;
+
+	data->signs = NULL;
+
+	ctx = isl_basic_set_get_ctx(bset);
+	data->signs = isl_alloc_array(ctx, int,
+					isl_basic_set_dim(bset, isl_dim_all));
+
+	if (isl_basic_set_dims_get_sign(bset, isl_dim_set, 0, dim,
+					data->signs + nparam) < 0)
+		goto error;
+	if (isl_basic_set_dims_get_sign(bset, isl_dim_param, 0, nparam,
+					data->signs) < 0)
+		goto error;
+
+	r = propagate_on_domain(bset, isl_qpolynomial_copy(data->poly), data);
+
+	free(data->signs);
+
+	return r;
+error:
+	free(data->signs);
+	isl_basic_set_free(bset);
+	return -1;
+}
+
+static int qpolynomial_bound_on_domain_range(__isl_take isl_basic_set *bset,
+	__isl_take isl_qpolynomial *poly, struct range_data *data)
+{
+	unsigned nparam = isl_basic_set_dim(bset, isl_dim_param);
+	unsigned nvar = isl_basic_set_dim(bset, isl_dim_set);
+	isl_set *set = NULL;
+
+	if (!bset)
+		goto error;
+
+	if (nvar == 0)
+		return add_guarded_poly(bset, poly, data);
+
+	set = isl_set_from_basic_set(bset);
+	set = isl_set_split_dims(set, isl_dim_param, 0, nparam);
+	set = isl_set_split_dims(set, isl_dim_set, 0, nvar);
+
+	data->poly = poly;
+
+	data->test_monotonicity = 1;
+	if (isl_set_foreach_basic_set(set, &basic_guarded_poly_bound, data) < 0)
+		goto error;
+
+	isl_set_free(set);
+	isl_qpolynomial_free(poly);
+
+	return 0;
+error:
+	isl_set_free(set);
+	isl_qpolynomial_free(poly);
+	return -1;
+}
+
+int isl_qpolynomial_bound_on_domain_range(__isl_take isl_basic_set *bset,
+	__isl_take isl_qpolynomial *poly, struct isl_bound *bound)
+{
+	struct range_data data;
+	int r;
+
+	data.pwf = bound->pwf;
+	data.pwf_tight = bound->pwf_tight;
+	data.tight = bound->check_tight;
+	if (bound->type == isl_fold_min)
+		data.sign = -1;
+	else
+		data.sign = 1;
+
+	r = qpolynomial_bound_on_domain_range(bset, poly, &data);
+
+	bound->pwf = data.pwf;
+	bound->pwf_tight = data.pwf_tight;
+
+	return r;
+}