[Bug rtl-optimization/54456] New: [4.8 Regression] ICE: in init_seqno, at sel-sched.c:6797 with -fschedule-insns -fselective-scheduling

[Bug rtl-optimization/54456] New: [4.8 Regression] ICE: in init_seqno, at sel-sched.c:6797 with -fschedule-insns -fselective-scheduling

[zsojka at seznam dot cz]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54456

             Bug #: 54456
           Summary: [4.8 Regression] ICE: in init_seqno, at
                    sel-sched.c:6797 with -fschedule-insns
                    -fselective-scheduling
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: zsojka@seznam.cz


Created attachment 28119
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28119
reduced testcase

Compiler output:
$ gcc -fschedule-insns -fselective-scheduling --param
max-sched-extend-regions-iters=8 testcase.c 
testcase.c: In function 'foo':
testcase.c:5:1: internal compiler error: in init_seqno, at sel-sched.c:6797
 }
 ^
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

(gdb) bt
#0  0x0000000001131fc0 in internal_error(char const*, ...) ()
#1  0x0000000001130b74 in fancy_abort(char const*, int, char const*) ()
#2  0x00000000009aa0bf in init_seqno(bitmap_head_def*, basic_block_def*) () at
/mnt/svn/gcc-trunk/gcc/sel-sched.c:6797
#3  0x00000000009b7aa1 in sel_sched_region(int) () at
/mnt/svn/gcc-trunk/gcc/sel-sched.c:7520
#4  0x00000000009b923a in run_selective_scheduling() () at
/mnt/svn/gcc-trunk/gcc/sel-sched.c:7709
#5  0x0000000000988ffe in rest_of_handle_sched() () at
/mnt/svn/gcc-trunk/gcc/sched-rgn.c:3489
#6  0x000000000090092f in execute_one_pass(opt_pass*) () at
/mnt/svn/gcc-trunk/gcc/passes.c:2157
#7  0x0000000000900ce5 in execute_pass_list(opt_pass*) () at
/mnt/svn/gcc-trunk/gcc/passes.c:2212
#8  0x0000000000900cf7 in execute_pass_list(opt_pass*) () at
/mnt/svn/gcc-trunk/gcc/passes.c:2213
#9  0x00000000006bdd88 in expand_function(cgraph_node*) () at
/mnt/svn/gcc-trunk/gcc/cgraphunit.c:1609
#10 0x00000000006bff02 in compile() () at
/mnt/svn/gcc-trunk/gcc/cgraphunit.c:1803
#11 0x00000000006c0225 in finalize_compilation_unit() () at
/mnt/svn/gcc-trunk/gcc/cgraphunit.c:2089
#12 0x00000000005a1dc0 in c_write_global_declarations() () at
/mnt/svn/gcc-trunk/gcc/c/c-decl.c:10116
#13 0x00000000009e8475 in compile_file() () at
/mnt/svn/gcc-trunk/gcc/toplev.c:560
#14 0x00000000009ea03a in toplev_main(int, char**) () at
/mnt/svn/gcc-trunk/gcc/toplev.c:1863
#15 0x00007ffff6e784bd in __libc_start_main () from /lib64/libc.so.6
#16 0x0000000000584d01 in _start ()

Tested revisions:
r190830 - crash
4.7 r188682 - OK

[Bug rtl-optimization/54456] [4.8 Regression] ICE: in init_seqno, at sel-sched.c:6797 with -fschedule-insns -fselective-scheduling

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54456

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-09-02
                 CC|                            |ebotcazou at gcc dot
                   |                            |gnu.org
   Target Milestone|---                         |4.8.0
     Ever Confirmed|0                           |1

--- Comment #1 from H.J. Lu <hjl.tools at gmail dot com> 2012-09-02 15:15:37 UTC ---
It was caused by revision 187913:

http://gcc.gnu.org/ml/gcc-cvs/2012-05/msg00912.html

[Bug rtl-optimization/54456] [4.8 Regression] ICE: in init_seqno, at sel-sched.c:6797 with -fschedule-insns -fselective-scheduling

[ebotcazou at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54456

--- Comment #2 from Eric Botcazou <ebotcazou at gcc dot gnu.org> 2012-09-02 20:06:46 UTC ---
Any specialist of selective scheduling interested here?  Otherwise:

Index: sched-rgn.c
===================================================================
--- sched-rgn.c (revision 190863)
+++ sched-rgn.c (working copy)
@@ -3473,7 +3473,7 @@ static bool
 gate_handle_sched (void)
 {
 #ifdef INSN_SCHEDULING
-  return flag_schedule_insns && dbg_cnt (sched_func);
+  return optimize > 0 && flag_schedule_insns && dbg_cnt (sched_func);
 #else
   return 0;
 #endif

is certainly good enough and would eliminate this whole class of ICEs.

[Bug rtl-optimization/54456] [4.8 Regression] ICE: in init_seqno, at sel-sched.c:6797 with -fschedule-insns -fselective-scheduling

[ebotcazou at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54456

--- Comment #3 from Eric Botcazou <ebotcazou at gcc dot gnu.org> 2012-09-04 19:05:43 UTC ---
Author: ebotcazou
Date: Tue Sep  4 19:05:38 2012
New Revision: 190947

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=190947
Log:
    PR rtl-optimization/54456
    * sched-rgn.c (gate_handle_sched): Return 1 only if optimize > 0.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/sched-rgn.c

[Bug rtl-optimization/54456] [4.8 Regression] ICE: in init_seqno, at sel-sched.c:6797 with -fschedule-insns -fselective-scheduling

[ebotcazou at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54456

Eric Botcazou <ebotcazou at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED

--- Comment #4 from Eric Botcazou <ebotcazou at gcc dot gnu.org> 2012-09-04 19:12:23 UTC ---
Patch applied.