On 12/26/2013 04:41 AM, Senthil Kumar Selvaraj wrote:
> Hi,
>
> gcc.c-torture/compile/pr34856.c and a couple of other tests segfault
> for the AVR target. Looking at the code, I found that the
> x_ira_register_move_cost array[TImode] is NULL, while the code goes on
> to dereference it (ira_register_move_cost
> [ALLOCNO_MODE (a)][best][aclass] at line 1832).
>
> I looked at the code that populates the array, and found that it does
> explicitly allow the array to have NULL entries for certain modes,
> atleast during initialization.
>
> I'm not really sure how this should be fixed - is NULL valid or is the
> AVR target violating some invariant?
>
The following patch fixes the problem.
Committed as rev. 206606.
2014-01-14 Vladimir Makarov <vmaka...@redhat.com>
* ira-costs.c (find_costs_and_classes): Add missed
ira_init_register_move_cost_if_necessary.
Index: ira-costs.c
===================================================================
--- ira-costs.c (revision 206579)
+++ ira-costs.c (working copy)
@@ -1827,6 +1827,7 @@ find_costs_and_classes (FILE *dump_file)
int ind = cost_classes_ptr->index[aclass];
ira_assert (ind >= 0);
+ ira_init_register_move_cost_if_necessary (ALLOCNO_MODE (a));
ira_add_allocno_pref (a, ira_class_hard_regs[best][0],
(a_costs[ind] - ALLOCNO_CLASS_COST (a))
/ (ira_register_move_cost
