------- Comment #3 from jakub at gcc dot gnu dot org 2008-09-02 16:44 -------
Why got this even marked as regression? GCC 4.3.1 didn't support
-ftree-loop-distribution, it is a new option, so it can't regress.
The loop in question is:
<bb 8>:
# state_89 = PHI <state_17(9), state_5(7)>
# prephitmp.18_6 = PHI <state_89(9), pretmp.17_59(7)>
state_17 = state_89->next_alt_state;
state_89->next_alt_state = prephitmp.18_6;
first_free_alt_state_lsm.29_18 = state_89;
if (state_17 != 0B)
goto <bb 9>;
else
goto <bb 10>;
<bb 9>:
goto <bb 8>;
and gets distributed into:
<bb 16>:
# state_62 = PHI <state_22(17), state_5(7)>
# prephitmp.18_26 = PHI <state_62(17), pretmp.17_59(7)>
state_22 = state_62->next_alt_state;
state_62->next_alt_state = prephitmp.18_26;
if (state_22 != 0B)
goto <bb 17>;
else
goto <bb 18>;
<bb 17>:
goto <bb 16>;
<bb 18>:
# prephitmp.18_90 = PHI <prephitmp.18_26(16)>
<bb 8>:
# state_89 = PHI <state_17(9), state_5(18)>
state_17 = state_89->next_alt_state;
state_89->next_alt_state = prephitmp.18_90;
first_free_alt_state_lsm.29_18 = state_89;
if (state_17 != 0B)
goto <bb 9>;
else
goto <bb 10>;
<bb 9>:
goto <bb 8>;
Perhaps tree-loop-distribution.c is confused by a PHI depending on previous PHI
result?
--
jakub at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |spop at gcc dot gnu dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36908
