------- Additional Comments From steven at gcc dot gnu dot org 2004-12-20
09:44 -------
At the start of the alias pass:
(gdb)
1593 invalidate_name_tags (vars_to_rename);
(gdb) p debug_bitmap (vars_to_rename)
first = 0xd73d10 current = 0xd73d10 indx = 0
0xd73d10 next = (nil) prev = (nil) indx = 0
bits = { 1 3 7 9 50 }
Then in prepare_use_operand_for_rename we have for the first V_MAY_DEF:
409 FOR_EACH_SSA_MAYDEF_OPERAND (def_p, use_p, stmt, iter)
(gdb)
411 if (prepare_use_operand_for_rename (use_p, &uid))
(gdb) step
prepare_use_operand_for_rename (op_p={use = 0x2a95a358d0}, uid_p=0x7fbfffc608)
at tree-into-ssa.c:562
562 tree use = USE_FROM_PTR (op_p);
563 tree var = (TREE_CODE (use) != SSA_NAME) ? use : SSA_NAME_VAR (use);
564 *uid_p = var_ann (var)->uid;
(gdb) p debug_generic_expr (use)
NMT.24D.1619
(gdb) p debug_generic_expr (var)
NMT.24D.1619
$47 = void
(gdb) p *uid_p
$46 = 51
Then we have:
567 if (vars_to_rename && !bitmap_bit_p (vars_to_rename, *uid_p))
So the bug seems to be in the alias pass, it just doesn't name the NMT
for renaming at all.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19080
