[PATCH] rs6000: Fix memory leak in rs6000_density_test

[Richard Sandiford via Gcc-patches]

rs6000_density_test has an early exit test between a call
to get_loop_body and the corresponding free.  This would
lead to a memory leak if the early exit is taken.

Tested on powerpc64le-linux-gnu.  It's obvious that moving the
test avoids the leak, but there are multiple ways to write it,
so: OK to install?

Richard


gcc/
        * config/rs6000/rs6000.c (rs6000_density_test): Move early
        exit test further up the function.
---
 gcc/config/rs6000/rs6000.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index acba4d9f26c..01a95591a5d 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -5289,20 +5289,19 @@ struct rs6000_cost_data
 static void
 rs6000_density_test (rs6000_cost_data *data)
 {
-  struct loop *loop = data->loop_info;
-  basic_block *bbs = get_loop_body (loop);
-  int nbbs = loop->num_nodes;
-  loop_vec_info loop_vinfo = loop_vec_info_for_loop (data->loop_info);
-  int vec_cost = data->cost[vect_body], not_vec_cost = 0;
-  int i, density_pct;
-
   /* This density test only cares about the cost of vector version of the
      loop, so immediately return if we are passed costing for the scalar
      version (namely computing single scalar iteration cost).  */
   if (data->costing_for_scalar)
     return;
 
-  for (i = 0; i < nbbs; i++)
+  struct loop *loop = data->loop_info;
+  basic_block *bbs = get_loop_body (loop);
+  int nbbs = loop->num_nodes;
+  loop_vec_info loop_vinfo = loop_vec_info_for_loop (data->loop_info);
+  int vec_cost = data->cost[vect_body], not_vec_cost = 0;
+
+  for (int i = 0; i < nbbs; i++)
     {
       basic_block bb = bbs[i];
       gimple_stmt_iterator gsi;
@@ -5322,7 +5321,7 @@ rs6000_density_test (rs6000_cost_data *data)
     }
 
   free (bbs);
-  density_pct = (vec_cost * 100) / (vec_cost + not_vec_cost);
+  int density_pct = (vec_cost * 100) / (vec_cost + not_vec_cost);
 
   if (density_pct > rs6000_density_pct_threshold
       && vec_cost + not_vec_cost > rs6000_density_size_threshold)