[Bug middle-end/37951] -ftree-parallelize-loops=2 fails for MA57

["dennis dot wassel at googlemail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #5 from dennis dot wassel at googlemail dot com  2008-11-25 11:26 -------
gfortran also produces ICEs in this context:

gfortran -O1 -fdump-tree-vect-details -ftree-vectorize
-ftree-parallelize-loops=2 -c ma57.f
ma57.f: In function 'ma57id':
ma57.f:131: internal compiler error: Segmentation fault

gfortran -O3 -fdump-tree-vect-details -ftree-vectorize
-ftree-parallelize-loops=2 -c ma57.f
ma57.f: In function 'ma57sd':
ma57.f:1538: internal compiler error: Segmentation fault


Throwing this into the debugger gives

Starting program: /localdata/libexec/gcc/i686-pc-linux-gnu/4.3.2/f951 ma57.f
-ffixed-form -quiet -dumpbase ma57.f -march=athlon64 -auxbase ma57 -O1
-fdump-tree-vect-details -ftree-vectorize -ftree-parallelize-loops=2
-fintrinsic-modules-path
/localdata/bin/../lib/gcc/i686-pc-linux-gnu/4.3.2/finclude -o /tmp/ccWSWloU.s
Failed to read a valid object file image from memory.

Program received signal SIGSEGV, Segmentation fault.
0xb7ce06f9 in free () from /lib/tls/i686/cmov/libc.so.6
(gdb) bt
#0  0xb7ce06f9 in free () from /lib/tls/i686/cmov/libc.so.6
#1  0xb7cdcf43 in _IO_free_backup_area () from /lib/tls/i686/cmov/libc.so.6
#2  0xb7cdafb2 in _IO_file_overflow () from /lib/tls/i686/cmov/libc.so.6
#3  0xb7cda51b in _IO_file_xsputn () from /lib/tls/i686/cmov/libc.so.6
#4  0xb7cb675f in vfprintf () from /lib/tls/i686/cmov/libc.so.6
#5  0xb7cbf2e2 in fprintf () from /lib/tls/i686/cmov/libc.so.6
#6  0x083a634e in vect_print_dump_info (vl=REPORT_DETAILS) at
/localdata/install/gcc/gcc-4.3.2/gcc/tree-vectorizer.c:1503
#7  0x0839549a in vect_analyze_loop_form (loop=0xb796c370) at
/localdata/install/gcc/gcc-4.3.2/gcc/tree-vect-analyze.c:4028
#8  0x0830475d in parallelize_loops () at
/localdata/install/gcc/gcc-4.3.2/gcc/tree-parloops.c:280
#9  0x08355be5 in tree_parallelize_loops () at
/localdata/install/gcc/gcc-4.3.2/gcc/tree-ssa-loop.c:486
#10 0x082466ea in execute_one_pass (pass=0x875c440) at
/localdata/install/gcc/gcc-4.3.2/gcc/passes.c:1122
#11 0x082469ef in execute_pass_list (pass=0x875c440) at
/localdata/install/gcc/gcc-4.3.2/gcc/passes.c:1175
#12 0x08246a10 in execute_pass_list (pass=0x875c100) at
/localdata/install/gcc/gcc-4.3.2/gcc/passes.c:1176
#13 0x08246a10 in execute_pass_list (pass=0x875b900) at
/localdata/install/gcc/gcc-4.3.2/gcc/passes.c:1176
#14 0x082fe85a in tree_rest_of_compilation (fndecl=0xb7bda380) at
/localdata/install/gcc/gcc-4.3.2/gcc/tree-optimize.c:404
#15 0x084081fd in cgraph_expand_function (node=0xb7b87300) at
/localdata/install/gcc/gcc-4.3.2/gcc/cgraphunit.c:1157
#16 0x08408cc5 in cgraph_optimize () at
/localdata/install/gcc/gcc-4.3.2/gcc/cgraphunit.c:1220
#17 0x080e7c95 in gfc_be_parse_file (set_yydebug=0) at
/localdata/install/gcc/gcc-4.3.2/gcc/fortran/f95-lang.c:264
#18 0x082ca6f8 in toplev_main (argc=17, argv=0xbfe09354) at
/localdata/install/gcc/gcc-4.3.2/gcc/toplev.c:1042
#19 0x08127aff in main (argc=Cannot access memory at address 0xb72d8ff8
) at /localdata/install/gcc/gcc-4.3.2/gcc/main.c:35


If I remove -march=athlon64 flag, f951 just hangs/waits without causing any CPU
load. Trying to backtrace what it is doing does not give anything meaningful
(at least to me):

Starting program: /localdata/libexec/gcc/i686-pc-linux-gnu/4.3.2/f951 ma57.f
-ffixed-form -quiet -dumpbase ma57.f -auxbase ma57 -O1 -fdump-tree-vect-details
-ftree-vectorize -ftree-parallelize-loops=2 -fintrinsic-modules-path
/localdata/bin/../lib/gcc/i686-pc-linux-gnu/4.3.2/finclude -o /tmp/ccWSWloU.s
Failed to read a valid object file image from memory.

Program received signal SIGINT, Interrupt.
0xb7f34410 in ?? ()
(gdb) bt
#0  0xb7f34410 in ?? ()
#1  0xbfd446e8 in ?? ()
#2  0x00000002 in ?? ()
#3  0x00000000 in ?? ()

Hope this helps!


-- 

dennis dot wassel at googlemail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ice-on-valid-code


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37951