return pwqp;
}
+/* Read an affine expression from "s" with domain (space) "dom".
+ * We call accept_affine to parse a possibly piecewise affine expression
+ * and then check that the result is a single affine expression on
+ * a universe domain.
+ */
+static __isl_give isl_aff *read_aff_with_dom(struct isl_stream *s,
+ __isl_take isl_set *dom, struct vars *v)
+{
+ isl_aff *aff = NULL;
+ isl_pw_aff *pwaff = NULL;
+
+ if (!isl_set_plain_is_universe(dom))
+ isl_die(s->ctx, isl_error_invalid,
+ "expecting universe domain", goto error);
+
+ if (!isl_set_is_params(dom) && isl_stream_eat(s, ISL_TOKEN_TO))
+ goto error;
+
+ if (isl_stream_eat(s, '['))
+ goto error;
+
+ pwaff = accept_affine(s, isl_set_get_space(dom), v);
+
+ if (isl_stream_eat(s, ']'))
+ goto error;
+ if (isl_stream_eat(s, '}'))
+ goto error;
+
+ if (!pwaff)
+ goto error;
+
+ if (pwaff->n != 1)
+ isl_die(s->ctx, isl_error_invalid,
+ "expecting single affine expression", goto error);
+ if (!isl_set_plain_is_universe(pwaff->p[0].set))
+ isl_die(s->ctx, isl_error_invalid,
+ "expecting universe domain", goto error);
+
+ aff = isl_aff_copy(pwaff->p[0].aff);
+
+ vars_free(v);
+ isl_pw_aff_free(pwaff);
+ isl_set_free(dom);
+ return aff;
+error:
+ vars_free(v);
+ isl_pw_aff_free(pwaff);
+ isl_set_free(dom);
+ return NULL;
+}
+
+/* Is the next token an identifer not in "v"?
+ */
+static int next_is_fresh_ident(struct isl_stream *s, struct vars *v)
+{
+ int n = v->n;
+ int fresh;
+ struct isl_token *tok;
+
+ tok = isl_stream_next_token(s);
+ if (!tok)
+ return 0;
+ fresh = tok->type == ISL_TOKEN_IDENT && vars_pos(v, tok->u.s, -1) >= n;
+ isl_stream_push_token(s, tok);
+
+ vars_drop(v, v->n - n);
+
+ return fresh;
+}
+
+/* Read an affine expression from "s".
+ * We first read the domain of the affine expression, which may be
+ * a parameter space or a set, and then call read_aff_with_dom.
+ * The tricky part is that we don't know if the domain is a set or not,
+ * so when we are trying to read the domain, we may actually be reading
+ * the affine expression itself (defined on a parameter domains)
+ * If the tuple we are reading is named, we assume it's the domain.
+ * Also, if inside the tuple, the first thing we find is a nested tuple
+ * or a new identifier, we again assume it's the domain.
+ * Otherwise, we assume we are reading an affine expression.
+ */
+__isl_give isl_aff *isl_stream_read_aff(struct isl_stream *s)
+{
+ struct vars *v;
+ struct isl_token *tok;
+ isl_set *dom = NULL;
+
+ v = vars_new(s->ctx);
+ if (!v)
+ return NULL;
+
+ dom = isl_set_universe(isl_space_params_alloc(s->ctx, 0));
+ if (next_is_tuple(s)) {
+ dom = read_tuple(s, dom, isl_dim_param, v);
+ if (isl_stream_eat(s, ISL_TOKEN_TO))
+ goto error;
+ }
+ tok = isl_stream_next_token(s);
+ if (!tok || tok->type != '{') {
+ isl_stream_error(s, tok, "expecting '{'");
+ goto error;
+ }
+ isl_token_free(tok);
+ tok = isl_stream_next_token(s);
+ if (tok && (tok->type == ISL_TOKEN_IDENT || tok->is_keyword)) {
+ isl_stream_push_token(s, tok);
+ dom = read_tuple(s, dom, isl_dim_set, v);
+ return read_aff_with_dom(s, dom, v);
+ }
+ if (!tok || tok->type != '[') {
+ isl_stream_error(s, tok, "expecting '['");
+ goto error;
+ }
+ if (next_is_tuple(s) || next_is_fresh_ident(s, v)) {
+ isl_stream_push_token(s, tok);
+ dom = read_tuple(s, dom, isl_dim_set, v);
+ } else
+ isl_stream_push_token(s, tok);
+
+ return read_aff_with_dom(s, dom, v);
+error:
+ if (tok)
+ isl_stream_push_token(s, tok);
+ vars_free(v);
+ isl_set_free(dom);
+ return NULL;
+}
+
+__isl_give isl_aff *isl_aff_read_from_str(isl_ctx *ctx, const char *str)
+{
+ isl_aff *aff;
+ struct isl_stream *s = isl_stream_new_str(ctx, str);
+ if (!s)
+ return NULL;
+ aff = isl_stream_read_aff(s);
+ isl_stream_free(s);
+ return aff;
+}
+
/* Read an isl_pw_multi_aff from "s".
* We currently read a generic object and if it turns out to be a set or
* a map, we convert that to an isl_pw_multi_aff.