isl_map_simplify.c: remove_duplicate_divs: avoid NULL pointer dereference

[platform/upstream/isl.git] / isl_map_simplify.c

diff --git a/isl_map_simplify.c b/isl_map_simplify.c
index 5327cc8..18daf94 100644 (file)
--- a/isl_map_simplify.c
+++ b/isl_map_simplify.c
@@ -527,7 +527,7 @@ static struct isl_basic_map *eliminate_divs_ineq(
                        continue;
                *progress = 1;
                bmap = isl_basic_map_eliminate_vars(bmap, (off-1)+d, 1);
-               if (ISL_F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
+               if (!bmap || ISL_F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
                        break;
                bmap = isl_basic_map_drop_div(bmap, d);
                if (!bmap)
@@ -645,13 +645,16 @@ static struct isl_basic_map *remove_duplicate_divs(
        int k, l, h;
        int bits;
        struct isl_blk eq;
-       unsigned total_var = isl_dim_total(bmap->dim);
-       unsigned total = total_var + bmap->n_div;
+       unsigned total_var;
+       unsigned total;
        struct isl_ctx *ctx;
 
-       if (bmap->n_div <= 1)
+       if (!bmap || bmap->n_div <= 1)
                return bmap;
 
+       total_var = isl_dim_total(bmap->dim);
+       total = total_var + bmap->n_div;
+
        ctx = bmap->ctx;
        for (k = bmap->n_div - 1; k >= 0; --k)
                if (!isl_int_is_zero(bmap->div[k][0]))
@@ -1015,7 +1018,7 @@ static struct isl_basic_map *remove_duplicate_constraints(
        unsigned total = isl_basic_map_total_dim(bmap);
        isl_int sum;
 
-       if (bmap->n_ineq <= 1)
+       if (!bmap || bmap->n_ineq <= 1)
                return bmap;
 
        size = round_up(4 * (bmap->n_ineq+1) / 3 - 1);