[Bug rtl-optimization/54343] New: RTL postreload leaks DF memory

[Bug rtl-optimization/54343] New: RTL postreload leaks DF memory

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54343

             Bug #: 54343
           Summary: RTL postreload leaks DF memory
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: rguenth@gcc.gnu.org


With valgrind on the testcase from PR54146 you can see leaks of the kind

==28803== 3,984 bytes in 249 blocks are definitely lost in loss record 28,125
of 29,883
==28803==    at 0x4C29ADD: malloc (in
/usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==28803==    by 0xCE28D7: xmalloc (xmalloc.c:147)
==28803==    by 0x6B064D: df_refs_add_to_chains(df_collection_rec*,
basic_block_def*, rtx_def*) (df-scan.c:2669)
==28803==    by 0x6B5144: df_bb_refs_record(int, bool) (df-scan.c:3644)
==28803==    by 0x6B524C: df_scan_blocks() (df-scan.c:678)
==28803==    by 0x7B6B7D: rest_of_handle_reload() (ira.c:4390)
==28803==    by 0x818C4A: execute_one_pass(opt_pass*) (passes.c:2157)
==28803==    by 0x818F94: execute_pass_list(opt_pass*) (passes.c:2212)
==28803==    by 0x818FA6: execute_pass_list(opt_pass*) (passes.c:2213)
==28803==    by 0x68F583: expand_function(cgraph_node*) (cgraphunit.c:1609)
==28803==    by 0x6909E8: compile() (cgraphunit.c:1714)
==28803==    by 0x690F64: finalize_compilation_unit() (cgraphunit.c:2089)

do_reload re-adds the live problem and calls run_fast_dce.  Either that
or subsequent passes that end up removing instructions do not bother
with freeing associated DF info.  At least I don't see that delete_insn
calls df_insn_delete or so.  Thus keeping DF initialized throughout
postreload may be not the best idea ...

[Bug rtl-optimization/54343] RTL postreload leaks DF memory

[steven at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54343

Steven Bosscher <steven at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-08-21
     Ever Confirmed|0                           |1

--- Comment #1 from Steven Bosscher <steven at gcc dot gnu.org> 2012-08-21 11:50:19 UTC ---
> Thus keeping DF initialized throughout
> postreload may be not the best idea ...

The problem is not in DF, but in the passes that don't properly update the info
for it. Hopefully with df_refs in an alloc-pool it'll be easier where the ref
vecs leak from...

[Bug rtl-optimization/54343] RTL postreload leaks DF memory

[steven at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54343

Steven Bosscher <steven at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |steven at gcc dot gnu.org

--- Comment #2 from Steven Bosscher <steven at gcc dot gnu.org> 2012-08-21 19:20:10 UTC ---
May be related to PR54332 ...

[Bug rtl-optimization/54343] RTL postreload leaks DF memory

[dnovillo at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54343

Diego Novillo <dnovillo at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dnovillo at gcc dot gnu.org

--- Comment #3 from Diego Novillo <dnovillo at gcc dot gnu.org> 2012-08-21 21:25:20 UTC ---
HJ's fix for PR 54332 will probably fix this one, too.  Could you re-test?

Thanks.

[Bug rtl-optimization/54343] RTL postreload leaks DF memory

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54343

--- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-08-22 09:32:13 UTC ---
(In reply to comment #3)
> HJ's fix for PR 54332 will probably fix this one, too.  Could you re-test?
> 
> Thanks.

Doesn't fix it.

==18936== 3,984 bytes in 249 blocks are definitely lost in loss record 28,126
of 29,883
==18936==    at 0x4C29ADD: malloc (in
/usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==18936==    by 0xCE2D27: xmalloc (xmalloc.c:147)
==18936==    by 0x6B05FD: df_refs_add_to_chains(df_collection_rec*,
basic_block_def*, rtx_def*) (df-scan.c:2669)
==18936==    by 0x6B50B4: df_bb_refs_record(int, bool) (df-scan.c:3644)
==18936==    by 0x6B51BC: df_scan_blocks() (df-scan.c:678)
==18936==    by 0x7B6C1D: rest_of_handle_reload() (ira.c:4390)
==18936==    by 0x818CEA: execute_one_pass(opt_pass*) (passes.c:2157)
==18936==    by 0x819034: execute_pass_list(opt_pass*) (passes.c:2212)
==18936==    by 0x819046: execute_pass_list(opt_pass*) (passes.c:2213)
==18936==    by 0x68F533: expand_function(cgraph_node*) (cgraphunit.c:1609)
==18936==    by 0x690998: compile() (cgraphunit.c:1714)
==18936==    by 0x690F14: finalize_compilation_unit() (cgraphunit.c:2089)

[Bug rtl-optimization/54343] RTL postreload leaks DF memory

[dnovillo at google dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54343

--- Comment #5 from dnovillo at google dot com <dnovillo at google dot com> 2012-08-22 12:43:02 UTC ---
On 2012-08-22 05:32 , rguenth at gcc dot gnu.org wrote:
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54343
>
> --- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-08-22 09:32:13 UTC ---
> (In reply to comment #3)
>> HJ's fix for PR 54332 will probably fix this one, too.  Could you re-test?
>>
>> Thanks.
>
> Doesn't fix it.

OK, then it wasn't related.  Do you know if this started happening with 
rev 190402?


Diego.

[Bug rtl-optimization/54343] RTL postreload leaks DF memory

[rguenther at suse dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54343

--- Comment #6 from rguenther at suse dot de <rguenther at suse dot de> 2012-08-22 13:01:53 UTC ---
On Wed, 22 Aug 2012, dnovillo at google dot com wrote:

> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54343
> 
> --- Comment #5 from dnovillo at google dot com <dnovillo at google dot com> 2012-08-22 12:43:02 UTC ---
> On 2012-08-22 05:32 , rguenth at gcc dot gnu.org wrote:
> > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54343
> >
> > --- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-08-22 09:32:13 UTC ---
> > (In reply to comment #3)
> >> HJ's fix for PR 54332 will probably fix this one, too.  Could you re-test?
> >>
> >> Thanks.
> >
> > Doesn't fix it.
> 
> OK, then it wasn't related.  Do you know if this started happening with 
> rev 190402?

I don't and I don't believe it did.

[Bug rtl-optimization/54343] RTL postreload leaks DF memory

[steven at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54343

Steven Bosscher <steven at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #7 from Steven Bosscher <steven at gcc dot gnu.org> 2013-03-03 17:09:16 UTC ---
Perhaps Jakub can have a look at this memleak, too?
He's been on an impressive leak-plugging spree lately :-)

[Bug rtl-optimization/54343] RTL postreload leaks DF memory

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54343

Richard Biener <rguenth at gcc dot gnu.org> changed:

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

--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
I can't reproduce with the testcase and have never seen this kind of leak in
the last years.  So assuming fixed.