isl_stream_read_map: accept modulo expressions

Signed-off-by: Sven Verdoolaege <skimo@kotnet.org>

diff --git a/isl_input.c b/isl_input.c
index 79d4870..dca1442 100644 (file)
--- a/isl_input.c
+++ b/isl_input.c
@@ -183,6 +183,54 @@ error:
        return -1;
 }
 
+/* Given an affine expression aff, return an affine expression
+ * for aff % d, with d the next token on the stream, which is
+ * assumed to be a constant.
+ *
+ * We introduce an integer division q = [aff/d] and the result
+ * is set to aff - d q.
+ */
+static __isl_give isl_vec *affine_mod(struct isl_stream *s,
+       struct vars *v, __isl_take isl_vec *aff)
+{
+       struct isl_token *tok;
+       struct variable *var;
+       isl_vec *mod;
+
+       tok = isl_stream_next_token(s);
+       if (!tok || tok->type != ISL_TOKEN_VALUE) {
+               isl_stream_error(s, tok, "expecting constant value");
+               goto error;
+       }
+
+       if (vars_add_anon(v) < 0)
+               goto error;
+
+       var = v->v;
+
+       var->def = isl_vec_alloc(s->ctx, 2 + v->n);
+       if (!var->def)
+               goto error;
+       isl_seq_cpy(var->def->el + 1, aff->el, aff->size);
+       isl_int_set_si(var->def->el[1 + aff->size], 0);
+       isl_int_set(var->def->el[0], tok->u.v);
+
+       mod = isl_vec_alloc(v->ctx, 1 + v->n);
+       if (!mod)
+               goto error;
+
+       isl_seq_cpy(mod->el, aff->el, aff->size);
+       isl_int_neg(mod->el[aff->size], tok->u.v);
+
+       isl_vec_free(aff);
+       isl_token_free(tok);
+       return mod;
+error:
+       isl_vec_free(aff);
+       isl_token_free(tok);
+       return NULL;
+}
+
 static struct isl_vec *accept_affine(struct isl_stream *s, struct vars *v);
 static int read_div_definition(struct isl_stream *s, struct vars *v);
 
@@ -249,6 +297,8 @@ static __isl_give isl_vec *accept_affine_factor(struct isl_stream *s,
                isl_stream_error(s, tok, "expecting factor");
                goto error;
        }
+       if (isl_stream_eat_if_available(s, '%'))
+               return affine_mod(s, v, aff);
        if (isl_stream_eat_if_available(s, '*')) {
                isl_int f;
                isl_int_init(f);

diff --git a/isl_test.c b/isl_test.c
index 8af787d..4c65209 100644 (file)
--- a/isl_test.c
+++ b/isl_test.c
@@ -66,6 +66,14 @@ void test_parse(struct isl_ctx *ctx)
        isl_map_free(map);
        isl_map_free(map2);
 
+       str = "{[new,old] -> [new+1-2*[(new+1)/2],old+1-2*[(old+1)/2]]}";
+       map = isl_map_read_from_str(ctx, str, -1);
+       str = "{[new,old] -> [(new+1)%2,(old+1)%2]}";
+       map2 = isl_map_read_from_str(ctx, str, -1);
+       assert(isl_map_is_equal(map, map2));
+       isl_map_free(map);
+       isl_map_free(map2);
+
        test_parse_pwqp(ctx, "{ [i] -> i + [ (i + [i/3])/2 ] }");
 }