PR middle-end/41469

        * tree-eh.c (lower_resx): Resolve RESX with no source region to
        __builtin_trap.
        (gate_lower_resx): New.
        (gate_lower_eh_dispatch): Rename from gate_lower_ehcontrol.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@152185 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 53a8332..7e7367f 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2009-09-25  Richard Henderson  <rth@redhat.com>
+
+       PR middle-end/41469
+       * tree-eh.c (lower_resx): Resolve RESX with no source region to
+       __builtin_trap.
+       (gate_lower_resx): New.
+       (gate_lower_eh_dispatch): Rename from gate_lower_ehcontrol.
+
 2009-09-25  Anatoly Sokolov  <aesok@post.ru>
 
        * config/v850/v850.h (FUNCTION_VALUE): Remove.

diff --git a/gcc/testsuite/gcc.c-torture/compile/pr41469.c b/gcc/testsuite/gcc.c-torture/compile/pr41469.c
new file mode 100644 (file)
index 0000000..7813cb3
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr41469.c
@@ -0,0 +1,12 @@
+void
+af (void *a)
+{
+}
+void
+bf (void)
+{
+  int i = 1;
+  char v[i];
+  af (v);
+}
+

diff --git a/gcc/tree-eh.c b/gcc/tree-eh.c
index a1aa4b2..70c009d 100644 (file)
--- a/gcc/tree-eh.c
+++ b/gcc/tree-eh.c
@@ -2849,10 +2849,26 @@ lower_resx (basic_block bb, gimple stmt, struct pointer_map_t *mnt_map)
     dst_r = NULL;
 
   src_r = get_eh_region_from_number (gimple_resx_region (stmt));
-  src_nr = build_int_cst (NULL, src_r->index);
   gsi = gsi_last_bb (bb);
 
-  if (dst_r)
+  if (src_r == NULL)
+    {
+      /* We can wind up with no source region when pass_cleanup_eh shows
+        that there are no entries into an eh region and deletes it, but
+        then the block that contains the resx isn't removed.  This can
+        happen without optimization when the switch statement created by
+        lower_try_finally_switch isn't simplified to remove the eh case.
+
+        Resolve this by expanding the resx node to an abort.  */
+
+      fn = implicit_built_in_decls[BUILT_IN_TRAP];
+      x = gimple_build_call (fn, 0);
+      gsi_insert_before (&gsi, x, GSI_SAME_STMT);
+
+      while (EDGE_COUNT (bb->succs) > 0)
+       remove_edge (EDGE_SUCC (bb, 0));
+    }
+  else if (dst_r)
     {
       /* When we have a destination region, we resolve this by copying
         the excptr and filter values into place, and changing the edge
@@ -2903,6 +2919,7 @@ lower_resx (basic_block bb, gimple stmt, struct pointer_map_t *mnt_map)
          tree dst_nr = build_int_cst (NULL, dst_r->index);
 
          fn = implicit_built_in_decls[BUILT_IN_EH_COPY_VALUES];
+         src_nr = build_int_cst (NULL, src_r->index);
          x = gimple_build_call (fn, 2, dst_nr, src_nr);
          gsi_insert_before (&gsi, x, GSI_SAME_STMT);
 
@@ -2948,6 +2965,7 @@ lower_resx (basic_block bb, gimple stmt, struct pointer_map_t *mnt_map)
 
        case 0:
          fn = implicit_built_in_decls[BUILT_IN_EH_POINTER];
+         src_nr = build_int_cst (NULL, src_r->index);
          x = gimple_build_call (fn, 1, src_nr);
          var = create_tmp_var (ptr_type_node, NULL);
          var = make_ssa_name (var, x);
@@ -3000,9 +3018,9 @@ execute_lower_resx (void)
 }
 
 static bool
-gate_lower_ehcontrol (void)
+gate_lower_resx (void)
 {
-  return cfun->eh->region_tree != NULL;
+  return flag_exceptions != 0;
 }
 
 struct gimple_opt_pass pass_lower_resx =
@@ -3010,7 +3028,7 @@ struct gimple_opt_pass pass_lower_resx =
  {
   GIMPLE_PASS,
   "resx",                              /* name */
-  gate_lower_ehcontrol,                        /* gate */
+  gate_lower_resx,                     /* gate */
   execute_lower_resx,                  /* execute */
   NULL,                                        /* sub */
   NULL,                                        /* next */
@@ -3175,12 +3193,18 @@ execute_lower_eh_dispatch (void)
   return any_rewritten ? TODO_update_ssa_only_virtuals : 0;
 }
 
+static bool
+gate_lower_eh_dispatch (void)
+{
+  return cfun->eh->region_tree != NULL;
+}
+
 struct gimple_opt_pass pass_lower_eh_dispatch =
 {
  {
   GIMPLE_PASS,
   "ehdisp",                            /* name */
-  gate_lower_ehcontrol,                        /* gate */
+  gate_lower_eh_dispatch,              /* gate */
   execute_lower_eh_dispatch,           /* execute */
   NULL,                                        /* sub */
   NULL,                                        /* next */