Hi,

This patch is to fix the typos in the move_sese_region_to_fn.
As mentioned here [1], I tried to debug the test case
gcc.dg/graphite/pr83359.c with trunk, but I found it didn't
go into the hunk guard with "if (moved_orig_loop_num)".  So
I switched to commit 555758de90074 (also reproduced the ICE
with 555758de90074~ to ensure my used command step is correct),
I noticed the compilation of the test case only covers the
hunk

        else
          {
            moved_orig_loop_num[dloop->orig_loop_num] = -1;
            dloop->orig_loop_num = 0;
          }

it doesn't touch the hunk

        if ((*larray)[dloop->orig_loop_num] != NULL
            && get_loop (saved_cfun, dloop->orig_loop_num) == NULL)
          {
            if (moved_orig_loop_num[dloop->orig_loop_num] >= 0
                && moved_orig_loop_num[dloop->orig_loop_num] < 2)
              moved_orig_loop_num[dloop->orig_loop_num]++;
            dloop->orig_loop_num = (*larray)[dloop->orig_loop_num]->num;
          }

so the following hunk using dloop and guarded with 
"if (moved_orig_loop_num[orig_loop_num] == 2)" doesn't get executed.

It explains why the problem doesn't get exposed before.

By looking to the code using dloop, I think it's a copy/paste typo,
the assertion

              gcc_assert ((*larray)[dloop->orig_loop_num] != NULL
                          && (get_loop (saved_cfun, dloop->orig_loop_num)
                              == NULL));

would like to ensure the condition in the previous
loop iterating is true, that is:

        if ((*larray)[dloop->orig_loop_num] != NULL
            && get_loop (saved_cfun, dloop->orig_loop_num) == NULL)

But in that context, I think the expected original number has been
assigned to variable orig_loop_num by extracting from the arg0
of IFN_LOOP_DIST_ALIAS call.  So replace those ones.

Is it ok for trunk?

[1] https://gcc.gnu.org/pipermail/gcc-patches/2021-July/576367.html

BR,
Kewen
-----
gcc/ChangeLog:

        * tree-cfg.c (move_sese_region_to_fn): Fix typos on dloop.
diff --git a/gcc/tree-cfg.c b/gcc/tree-cfg.c
index 48ee8c011ab..9883eaaa9bf 100644
--- a/gcc/tree-cfg.c
+++ b/gcc/tree-cfg.c
@@ -7747,9 +7747,8 @@ move_sese_region_to_fn (struct function *dest_cfun, 
basic_block entry_bb,
 
   /* Fix up orig_loop_num.  If the block referenced in it has been moved
      to dest_cfun, update orig_loop_num field, otherwise clear it.  */
-  class loop *dloop = NULL;
   signed char *moved_orig_loop_num = NULL;
-  for (class loop *dloop : loops_list (dest_cfun, 0))
+  for (auto dloop : loops_list (dest_cfun, 0))
     if (dloop->orig_loop_num)
       {
        if (moved_orig_loop_num == NULL)
@@ -7787,11 +7786,10 @@ move_sese_region_to_fn (struct function *dest_cfun, 
basic_block entry_bb,
              /* If we have moved both loops with this orig_loop_num into
                 dest_cfun and the LOOP_DIST_ALIAS call is being moved there
                 too, update the first argument.  */
-             gcc_assert ((*larray)[dloop->orig_loop_num] != NULL
-                         && (get_loop (saved_cfun, dloop->orig_loop_num)
-                             == NULL));
+             gcc_assert ((*larray)[orig_loop_num] != NULL
+                         && (get_loop (saved_cfun, orig_loop_num) == NULL));
              tree t = build_int_cst (integer_type_node,
-                                     (*larray)[dloop->orig_loop_num]->num);
+                                     (*larray)[orig_loop_num]->num);
              gimple_call_set_arg (g, 0, t);
              update_stmt (g);
              /* Make sure the following loop will not update it.  */

Reply via email to