[Bug rtl-optimization/55719] [4.8 Regression] ICE: Segmentation fault
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55719 --- Comment #8 from Andreas Krebbel krebbel at gcc dot gnu.org 2013-01-11 16:43:56 UTC --- Author: krebbel Date: Fri Jan 11 16:43:49 2013 New Revision: 195109 URL: http://gcc.gnu.org/viewcvs?root=gccview=revrev=195109 Log: 2013-01-11 Andreas Krebbel andreas.kreb...@de.ibm.com PR target/55719 * config/s390/s390.c (s390_preferred_reload_class): Do not return NO_REGS for larl operands. (s390_reload_larl_operand): Use s390_load_address instead of emit_move_insn. 2013-01-11 Andreas Krebbel andreas.kreb...@de.ibm.com PR target/55719 * gcc.target/s390/pr55719.c: New testcase. Modified: trunk/gcc/ChangeLog trunk/gcc/config/s390/s390.c trunk/gcc/testsuite/ChangeLog
[Bug rtl-optimization/55719] [4.8 Regression] ICE: Segmentation fault
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55719 Andreas Krebbel krebbel at gcc dot gnu.org changed: What|Removed |Added Status|ASSIGNED|RESOLVED Resolution||FIXED --- Comment #9 from Andreas Krebbel krebbel at gcc dot gnu.org 2013-01-11 16:45:15 UTC --- Fixed with commit above.
[Bug rtl-optimization/55719] [4.8 Regression] ICE: Segmentation fault
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55719
Aldy Hernandez aldyh at gcc dot gnu.org changed:
What|Removed |Added
CC||aldyh at gcc dot gnu.org
--- Comment #4 from Aldy Hernandez aldyh at gcc dot gnu.org 2013-01-09
17:48:10 UTC ---
My brain's too small for such a big testcase. Further reduced testcase, and
reduced arguments.
// ./cc1 -quiet -O2 a.c -march=z10 -fPIC -I /tmp
static int glob_a, glob_b;
int foobar()
{
char buffer[100];
glob_a = 0;
glob_b = 0;
bar (buffer);
__builtin_memcpy(buffer, abc, 3);
buffer[7] = (char)(glob_a 8);
buffer[11] = (char)glob_b;
buffer[13] = (char)glob_a;
buffer[17] = (char)(glob_a 8);
return foo(0, 0, 0, 0);
}
[Bug rtl-optimization/55719] [4.8 Regression] ICE: Segmentation fault
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55719
Aldy Hernandez aldyh at gcc dot gnu.org changed:
What|Removed |Added
CC||rsandifo at gcc dot gnu.org
--- Comment #5 from Aldy Hernandez aldyh at gcc dot gnu.org 2013-01-09
18:45:34 UTC ---
I'm out of my depth here, but perhaps someone can give me a hint on how to
debug this further.
As alluded to earlier, this ICE only happens with sched-pressure scheduling.
The actual ICE happens in find_reloads_address_part(), where we have are
analyzing X=:
(const:DI (plus:DI (symbol_ref:DI (glob_b))
(const_int 3 [0x3])))
prefer_reload_class() returns NO_REGS, because legitimate_reload_constant_p()
returns false for the X above. So when we call force_const_mem() in
find_reloads_address_part...
if (CONSTANT_P (x)
(!targetm.legitimate_constant_p (mode, x)
|| targetm.preferred_reload_class (x, rclass) == NO_REGS))
{
x = force_const_mem (mode, x); -- HERE
force_const_mem() returns NULL because s390_cannot_force_const_mem() returns
true for the SYMBOL_REF in -fPIC mode.
Bottom line-- force_const_mem() returns NULL for a (const (plus SYMBOL_REF
CONST)) with -fPIC, and then we dereference this NULL.
Is the RTL correct?
Any hints?
[Bug rtl-optimization/55719] [4.8 Regression] ICE: Segmentation fault
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55719
Andreas Krebbel krebbel at gcc dot gnu.org changed:
What|Removed |Added
Status|NEW |ASSIGNED
AssignedTo|unassigned at gcc dot |krebbel at gcc dot gnu.org
|gnu.org |
--- Comment #6 from Andreas Krebbel krebbel at gcc dot gnu.org 2013-01-10
07:41:46 UTC ---
(In reply to comment #5)
I'm out of my depth here, but perhaps someone can give me a hint on how to
debug this further.
As alluded to earlier, this ICE only happens with sched-pressure scheduling.
The actual ICE happens in find_reloads_address_part(), where we have are
analyzing X=:
(const:DI (plus:DI (symbol_ref:DI (glob_b))
(const_int 3 [0x3])))
prefer_reload_class() returns NO_REGS, because legitimate_reload_constant_p()
returns false for the X above. So when we call force_const_mem() in
find_reloads_address_part...
if (CONSTANT_P (x)
(!targetm.legitimate_constant_p (mode, x)
|| targetm.preferred_reload_class (x, rclass) == NO_REGS))
{
x = force_const_mem (mode, x); -- HERE
force_const_mem() returns NULL because s390_cannot_force_const_mem() returns
true for the SYMBOL_REF in -fPIC mode.
Bottom line-- force_const_mem() returns NULL for a (const (plus SYMBOL_REF
CONST)) with -fPIC, and then we dereference this NULL.
Is the RTL correct?
Any hints?
I'm already testing a patch. We have an instruction (larl) which is able to
handle pc-relative symbol references. But it only allows even addends. symref +
odd addend is handled via secondary reload. I think it is invalid that
preferred reload class returns NO_REGS here.
[Bug rtl-optimization/55719] [4.8 Regression] ICE: Segmentation fault
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55719 --- Comment #7 from Andreas Krebbel krebbel at gcc dot gnu.org 2013-01-10 07:55:32 UTC --- Created attachment 29137 -- http://gcc.gnu.org/bugzilla/attachment.cgi?id=29137 Experimental fix This patch fixes the problem for me. I will use Aldys testcase when comitting since he reduced it a bit further.
[Bug rtl-optimization/55719] [4.8 Regression] ICE: Segmentation fault
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55719 Richard Biener rguenth at gcc dot gnu.org changed: What|Removed |Added Priority|P3 |P1
[Bug rtl-optimization/55719] [4.8 Regression] ICE: Segmentation fault
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55719 Richard Biener rguenth at gcc dot gnu.org changed: What|Removed |Added Keywords||ra Component|c |rtl-optimization --- Comment #1 from Richard Biener rguenth at gcc dot gnu.org 2012-12-17 10:10:44 UTC --- Backtrace is: ./cc1 -quiet -O3 ma_control_file.i -I include -march=z10 -mtune=z196 -fPIC /home/abuild/rpmbuild/BUILD/mariadb-5.5.28/storage/maria/ma_control_file.c: In function 'ma_control_file_open': /home/abuild/rpmbuild/BUILD/mariadb-5.5.28/storage/maria/ma_control_file.c:452:1: internal compiler error: Segmentation fault 0xa9ab75 crash_signal /space/rguenther/src/svn/trunk/gcc/toplev.c:334 0xa0ee4e find_reloads_address_part /space/rguenther/src/svn/trunk/gcc/reload.c:6140 0xa0c5a1 find_reloads_address /space/rguenther/src/svn/trunk/gcc/reload.c:5312 0xa0f112 find_reloads_subreg_address /space/rguenther/src/svn/trunk/gcc/reload.c:6233 0xa0b29a find_reloads_toplev /space/rguenther/src/svn/trunk/gcc/reload.c:4822 0xa0558f find_reloads(rtx_def*, int, int, int, short*) /space/rguenther/src/svn/trunk/gcc/reload.c:2910 0xa15eaa calculate_needs_all_insns /space/rguenther/src/svn/trunk/gcc/reload1.c:1519 reducing with a cross.
[Bug rtl-optimization/55719] [4.8 Regression] ICE: Segmentation fault
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55719 --- Comment #2 from Richard Biener rguenth at gcc dot gnu.org 2012-12-17 10:27:42 UTC --- Created attachment 28984 -- http://gcc.gnu.org/bugzilla/attachment.cgi?id=28984 autoreduced testcase
[Bug rtl-optimization/55719] [4.8 Regression] ICE: Segmentation fault
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55719 Andreas Krebbel krebbel at gcc dot gnu.org changed: What|Removed |Added Status|UNCONFIRMED |NEW Last reconfirmed||2012-12-17 Ever Confirmed|0 |1 --- Comment #3 from Andreas Krebbel krebbel at gcc dot gnu.org 2012-12-17 16:00:17 UTC --- Reghunt revealed r187064 as the culprit. This was the patch which enabled the sched-pressure scheduling by default on s390.
