http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46675
Uros Bizjak <ubizjak at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Component|middle-end |tree-optimization
--- Comment #4 from Uros Bizjak <ubizjak at gmail dot com> 2010-11-27 11:14:56
UTC ---
It is vrp2 pass that miscompiles attached preprocessed file.
gcc-build/gcc/cc1 -O2 -fprofile-use
************* _.122t.reassoc2:
--cut here--
<bb 291>:
# i_1950 = PHI <i_224(312), 0(290)>
# lastkey_1951 = PHI <key_1983(312), 0(290)>
vfr.11_1984 = vfr;
D.25742_1985 = vfr.11_1984->PC;
D.25743_1987 = vfr.11_1984->current_method;
D.25744_1988 = D.25743_1987->code_length;
if (D.25742_1985 >= D.25744_1988)
goto <bb 292>;
else
goto <bb 293>;
...
<bb 312>:
# prephitmp.1242_3787 = PHI <prephitmp.1236_3781(310), pretmp.1241_3786(311)>
D.25872_2132 = prephitmp.1242_3787->current_state;
merge_into (npc_2135, D.25872_2132);
printf (&"i = %i\n"[0], i_1950);
i_224 = i_1950 + 1;
if (i_224 < npairs_1969)
goto <bb 291>;
else
goto <bb 313>;
<bb 313>:
<bb 314>:
vfr.56_882 = vfr;
vfr.56_882->PC = -1;
goto <bb 14> (<L386>);
--cut here--
************* _.123t.vrp:
--cut here--
<bb 295>:
# lastkey_1951 = PHI <0(294), key_1983(315)>
i_1950 = 0;
vfr.11_1984 = vfr;
D.25742_1985 = vfr.11_1984->PC;
D.25743_1987 = vfr.11_1984->current_method;
D.25744_1988 = D.25743_1987->code_length;
if (D.25742_1985 >= D.25744_1988)
goto <bb 296>;
else
goto <bb 297>;
...
<bb 315>:
# prephitmp.1242_3787 = PHI <prephitmp.1236_3781(313), pretmp.1241_3786(314)>
D.25872_2132 = prephitmp.1242_3787->current_state;
merge_into (npc_2135, D.25872_2132);
printf (&"i = %i\n"[0], 0);
i_224 = 1;
if (npairs_1969 > 1)
goto <bb 295>;
else
goto <bb 316>;
<bb 316>:
--cut here--
See how i_1950 in _.123t.vrp dump gets assigned to zero and consequently i_224
to one.
