public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug optimization/13931] New: combiner much slower on big functions
@ 2004-01-30 12:41 bonzini at gnu dot org
  2004-01-30 12:41 ` [Bug optimization/13931] " bonzini at gnu dot org
                   ` (23 more replies)
  0 siblings, 24 replies; 25+ messages in thread
From: bonzini at gnu dot org @ 2004-01-30 12:41 UTC (permalink / raw)
  To: gcc-bugs

The combiner jumped up from 3.3.2's 8% to 3.4/3.5's 56% in the attached function. 
 
No. of lines in block            Run time 
600                                      0.36 
1200				    2.33 
1800                                    5.77 
2400                                   10.56 
 
There seems to be a quadratic bottleneck in combine.  distribute_notes has a loop that 
goes over all previous instructions.  distribute_notes calls reg_set_p, which calls set_of, 
which calls note_stores, which calls set_of_1, which calls reg_overlap_mentioned_p, 
which calls refers_to_regno_p... and all these show up quite at the top of the profile. 
 
# of instructions       function 
224,203,200  rtlanal.c:refers_to_regno_p 
150,433,200  rtlanal.c:reg_overlap_mentioned_p 
 75,561,636  rtlanal.c:note_stores 
 56,985,600  rtlanal.c:reg_referenced_p 
 49,576,316  regrename.c:validate_value_data 
 40,026,779  rtl.c:rtx_equal_p 
 28,740,658  flow.c:mark_set_1 
 27,562,800  combine.c:distribute_notes 
 25,928,400  rtlanal.c:set_of_1 
 15,840,000  rtlanal.c:reg_set_p 
 
This might be a duplicate of PR13775.

-- 
           Summary: combiner much slower on big functions
           Product: gcc
           Version: 3.4.0
            Status: UNCONFIRMED
          Severity: critical
          Priority: P2
         Component: optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bonzini at gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13931


^ permalink raw reply	[flat|nested] 25+ messages in thread
end of thread, other threads:[~2004-12-22 19:48 UTC | newest]

Thread overview: 25+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2004-01-30 12:41 [Bug optimization/13931] New: combiner much slower on big functions bonzini at gnu dot org
2004-01-30 12:41 ` [Bug optimization/13931] " bonzini at gnu dot org
2004-01-30 12:42 ` bonzini at gnu dot org
2004-01-30 17:23 ` [Bug optimization/13931] [3.4/3.5 Regression] " pinskia at gcc dot gnu dot org
2004-01-30 19:26 ` [Bug optimization/13931] [3.4/3.5 Regression] combiner much slower on big basic blocks bonzini at gnu dot org
2004-01-30 19:26 ` bonzini at gnu dot org
2004-02-04 16:39 ` pinskia at gcc dot gnu dot org
2004-03-08 23:03 ` mmitchel at gcc dot gnu dot org
2004-06-07  3:24 ` [Bug rtl-optimization/13931] " pinskia at gcc dot gnu dot org
2004-06-07 19:08 ` [Bug rtl-optimization/13931] [3.3/3.4/3.5 " pinskia at gcc dot gnu dot org
2004-06-07 20:44 ` pinskia at gcc dot gnu dot org
2004-06-07 20:54 ` pinskia at gcc dot gnu dot org
2004-06-07 21:13 ` ebotcazou at gcc dot gnu dot org
2004-06-18 23:47 ` mmitchel at gcc dot gnu dot org
2004-08-29 18:47 ` mmitchel at gcc dot gnu dot org
2004-10-30 20:02 ` [Bug rtl-optimization/13931] [3.3/3.4/4.0 " mmitchel at gcc dot gnu dot org
2004-10-30 20:03 ` mmitchel at gcc dot gnu dot org
2004-11-15 12:11 ` ebotcazou at gcc dot gnu dot org
2004-11-16  8:05 ` ebotcazou at gcc dot gnu dot org
2004-11-16  8:22 ` ebotcazou at gcc dot gnu dot org
2004-11-16  8:24 ` ebotcazou at gcc dot gnu dot org
2004-11-18 20:46 ` pinskia at gcc dot gnu dot org
2004-12-07 19:54 ` echristo at redhat dot com
2004-12-22 19:23 ` steven at gcc dot gnu dot org
2004-12-22 19:48 ` echristo at redhat dot com

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).