isl_polynomial.c: sort_divs: remove duplicate divs, if any

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

diff --git a/isl_polynomial.c b/isl_polynomial.c
index 1ef03da..17d99be 100644 (file)
--- a/isl_polynomial.c
+++ b/isl_polynomial.c
@@ -1067,9 +1067,13 @@ static int div_sort_cmp(const void *p1, const void *p2)
        return cmp_row(i1->div, i1->row, i2->row);
 }
 
+/* Sort divs and remove duplicates.
+ */
 static __isl_give isl_qpolynomial *sort_divs(__isl_take isl_qpolynomial *qp)
 {
        int i;
+       int skip;
+       int len;
        struct isl_div_sort_info *array = NULL;
        int *pos = NULL, *at = NULL;
        int *reordering = NULL;
@@ -1086,7 +1090,8 @@ static __isl_give isl_qpolynomial *sort_divs(__isl_take isl_qpolynomial *qp)
                                qp->div->n_row);
        pos = isl_alloc_array(qp->div->ctx, int, qp->div->n_row);
        at = isl_alloc_array(qp->div->ctx, int, qp->div->n_row);
-       reordering = isl_alloc_array(qp->div->ctx, int, qp->div->n_col - 2);
+       len = qp->div->n_col - 2;
+       reordering = isl_alloc_array(qp->div->ctx, int, len);
        if (!array || !pos || !at || !reordering)
                goto error;
 
@@ -1103,9 +1108,6 @@ static __isl_give isl_qpolynomial *sort_divs(__isl_take isl_qpolynomial *qp)
        for (i = 0; i < div_pos; ++i)
                reordering[i] = i;
 
-       for (i = 0; i < qp->div->n_row; ++i)
-               reordering[div_pos + array[i].row] = div_pos + i;
-
        for (i = 0; i < qp->div->n_row; ++i) {
                if (pos[array[i].row] == i)
                        continue;
@@ -1116,6 +1118,19 @@ static __isl_give isl_qpolynomial *sort_divs(__isl_take isl_qpolynomial *qp)
                pos[array[i].row] = i;
        }
 
+       skip = 0;
+       for (i = 0; i < len - div_pos; ++i) {
+               if (i > 0 &&
+                   isl_seq_eq(qp->div->row[i - skip - 1],
+                              qp->div->row[i - skip], qp->div->n_col)) {
+                       qp->div = isl_mat_drop_rows(qp->div, i - skip, 1);
+                       qp->div = isl_mat_drop_cols(qp->div,
+                                                   2 + div_pos + i - skip, 1);
+                       skip++;
+               }
+               reordering[div_pos + array[i].row] = div_pos + i - skip;
+       }
+
        qp->upoly = reorder(qp->upoly, reordering);
 
        if (!qp->upoly || !qp->div)