[Bug c++/13954] [tree-ssa] SRA does not work for classes that use inheritance with an empty base

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* [Bug c++/13954] [tree-ssa] SRA does not work for classes that use inheritance with an empty base
       [not found] <bug-13954-4@http.gcc.gnu.org/bugzilla/>
@ 2011-03-08 15:51 ` rguenth at gcc dot gnu.org
  2011-03-15 13:39 ` rguenth at gcc dot gnu.org
  2011-03-15 13:55 ` rguenth at gcc dot gnu.org
  2 siblings, 0 replies; 8+ messages in thread
From: rguenth at gcc dot gnu.org @ 2011-03-08 15:51 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13954

--- Comment #17 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-08 15:50:59 UTC ---
I have a patch, queued for 4.7.


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [Bug c++/13954] [tree-ssa] SRA does not work for classes that use inheritance with an empty base
       [not found] <bug-13954-4@http.gcc.gnu.org/bugzilla/>
  2011-03-08 15:51 ` [Bug c++/13954] [tree-ssa] SRA does not work for classes that use inheritance with an empty base rguenth at gcc dot gnu.org
@ 2011-03-15 13:39 ` rguenth at gcc dot gnu.org
  2011-03-15 13:55 ` rguenth at gcc dot gnu.org
  2 siblings, 0 replies; 8+ messages in thread
From: rguenth at gcc dot gnu.org @ 2011-03-15 13:39 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13954

--- Comment #18 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-15 13:37:42 UTC ---
Author: rguenth
Date: Tue Mar 15 13:37:23 2011
New Revision: 170994

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=170994
Log:
2011-03-15  Richard Guenther  <rguenther@suse.de>

    PR tree-optimization/13954
    * tree-ssa-sccvn.c (vn_reference_lookup_3): Look through memcpy
    and friends.

    * g++.dg/tree-ssa/pr13954.C: New testcase.

Added:
    trunk/gcc/testsuite/g++.dg/tree-ssa/pr13954.C
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-sccvn.c


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [Bug c++/13954] [tree-ssa] SRA does not work for classes that use inheritance with an empty base
       [not found] <bug-13954-4@http.gcc.gnu.org/bugzilla/>
  2011-03-08 15:51 ` [Bug c++/13954] [tree-ssa] SRA does not work for classes that use inheritance with an empty base rguenth at gcc dot gnu.org
  2011-03-15 13:39 ` rguenth at gcc dot gnu.org
@ 2011-03-15 13:55 ` rguenth at gcc dot gnu.org
  2 siblings, 0 replies; 8+ messages in thread
From: rguenth at gcc dot gnu.org @ 2011-03-15 13:55 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13954

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.7.0

--- Comment #19 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-15 13:41:43 UTC ---
Fixed.


^ permalink raw reply	[flat|nested] 8+ messages in thread

[parent not found: <bug-13954-1008@http.gcc.gnu.org/bugzilla/>]

* [Bug c++/13954] [tree-ssa] SRA does not work for classes that use inheritance with an empty base
       [not found] <bug-13954-1008@http.gcc.gnu.org/bugzilla/>
@ 2006-03-06 14:42 ` rguenth at gcc dot gnu dot org
  2006-10-24 12:34 ` rguenth at gcc dot gnu dot org
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 8+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2006-03-06 14:42 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #12 from rguenth at gcc dot gnu dot org  2006-03-06 14:41 -------
In principle this blocks optimization of tramp3d domain operations (if it were
not structure-aliasing fixing most of the problems).


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
OtherBugsDependingO|                            |22501
              nThis|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13954


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [Bug c++/13954] [tree-ssa] SRA does not work for classes that use inheritance with an empty base
       [not found] <bug-13954-1008@http.gcc.gnu.org/bugzilla/>
  2006-03-06 14:42 ` rguenth at gcc dot gnu dot org
@ 2006-10-24 12:34 ` rguenth at gcc dot gnu dot org
  2006-10-24 18:31 ` dberlin at gcc dot gnu dot org
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 8+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2006-10-24 12:34 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #13 from rguenth at gcc dot gnu dot org  2006-10-24 12:34 -------
We now get

<bb 2>:
  #   param_2 = V_MAY_DEF <param_1>;
  param.f1 = 0;
  #   param_6 = V_MAY_DEF <param_2>;
  #   SFT.0_7 = V_MAY_DEF <SFT.0_3>;
  #   NONLOCAL.6_8 = V_MAY_DEF <NONLOCAL.6_5>;
  #   NONLOCAL.12_13 = V_MAY_DEF <NONLOCAL.12_12>;
  #   NONLOCAL.18_16 = V_MAY_DEF <NONLOCAL.18_15>;
  #   NONLOCAL.24_19 = V_MAY_DEF <NONLOCAL.24_18>;
  #   NONLOCAL.30_22 = V_MAY_DEF <NONLOCAL.30_21>;
  #   NONLOCAL.36_25 = V_MAY_DEF <NONLOCAL.36_24>;
  __builtin_memcpy (&local, &param, 9);
  #   VUSE <SFT.0_7>;
  D.2668_4 = local.f1;
  if (D.2668_4 != 0) goto <L0>; else goto <L1>;

<L0>:;
  #   param_9 = V_MAY_DEF <param_6>;
  #   SFT.0_10 = V_MAY_DEF <SFT.0_7>;
  #   NONLOCAL.6_11 = V_MAY_DEF <NONLOCAL.6_8>;
  #   NONLOCAL.12_14 = V_MAY_DEF <NONLOCAL.12_13>;
  #   NONLOCAL.18_17 = V_MAY_DEF <NONLOCAL.18_16>;
  #   NONLOCAL.24_20 = V_MAY_DEF <NONLOCAL.24_19>;
  #   NONLOCAL.30_23 = V_MAY_DEF <NONLOCAL.30_22>;
  #   NONLOCAL.36_26 = V_MAY_DEF <NONLOCAL.36_25>;
  link_error ();

<L1>:;
  return;


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2005-12-09 04:36:34         |2006-10-24 12:34:46
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13954


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [Bug c++/13954] [tree-ssa] SRA does not work for classes that use inheritance with an empty base
       [not found] <bug-13954-1008@http.gcc.gnu.org/bugzilla/>
  2006-03-06 14:42 ` rguenth at gcc dot gnu dot org
  2006-10-24 12:34 ` rguenth at gcc dot gnu dot org
@ 2006-10-24 18:31 ` dberlin at gcc dot gnu dot org
  2009-09-26 15:30 ` rguenth at gcc dot gnu dot org
  2010-08-11 12:34 ` rguenth at gcc dot gnu dot org
  4 siblings, 0 replies; 8+ messages in thread
From: dberlin at gcc dot gnu dot org @ 2006-10-24 18:31 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #14 from dberlin at gcc dot gnu dot org  2006-10-24 18:31 -------
(In reply to comment #13)
> We now get
> 
> <bb 2>:
>   #   param_2 = V_MAY_DEF <param_1>;
>   param.f1 = 0;
>   #   param_6 = V_MAY_DEF <param_2>;
>   #   SFT.0_7 = V_MAY_DEF <SFT.0_3>;
>   #   NONLOCAL.6_8 = V_MAY_DEF <NONLOCAL.6_5>;
>   #   NONLOCAL.12_13 = V_MAY_DEF <NONLOCAL.12_12>;
>   #   NONLOCAL.18_16 = V_MAY_DEF <NONLOCAL.18_15>;
>   #   NONLOCAL.24_19 = V_MAY_DEF <NONLOCAL.24_18>;
>   #   NONLOCAL.30_22 = V_MAY_DEF <NONLOCAL.30_21>;
>   #   NONLOCAL.36_25 = V_MAY_DEF <NONLOCAL.36_24>;
>   __builtin_memcpy (&local, &param, 9);
>   #   VUSE <SFT.0_7>;
>   D.2668_4 = local.f1;
>   if (D.2668_4 != 0) goto <L0>; else goto <L1>;
> 
> <L0>:;
>   #   param_9 = V_MAY_DEF <param_6>;
>   #   SFT.0_10 = V_MAY_DEF <SFT.0_7>;
>   #   NONLOCAL.6_11 = V_MAY_DEF <NONLOCAL.6_8>;
>   #   NONLOCAL.12_14 = V_MAY_DEF <NONLOCAL.12_13>;
>   #   NONLOCAL.18_17 = V_MAY_DEF <NONLOCAL.18_16>;
>   #   NONLOCAL.24_20 = V_MAY_DEF <NONLOCAL.24_19>;
>   #   NONLOCAL.30_23 = V_MAY_DEF <NONLOCAL.30_22>;
>   #   NONLOCAL.36_26 = V_MAY_DEF <NONLOCAL.36_25>;
>   link_error ();
> 
> <L1>:;
>   return;
> 

Uh, there should only ever be one non-local var per function, and referenced
vars should be reset at the end of each function so why do you have multiple
NONLOCAL's here?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13954


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [Bug c++/13954] [tree-ssa] SRA does not work for classes that use inheritance with an empty base
       [not found] <bug-13954-1008@http.gcc.gnu.org/bugzilla/>
                   ` (2 preceding siblings ...)
  2006-10-24 18:31 ` dberlin at gcc dot gnu dot org
@ 2009-09-26 15:30 ` rguenth at gcc dot gnu dot org
  2010-08-11 12:34 ` rguenth at gcc dot gnu dot org
  4 siblings, 0 replies; 8+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2009-09-26 15:30 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #15 from rguenth at gcc dot gnu dot org  2009-09-26 15:30 -------
On trunk we get

<bb 2>:
  # .MEM_3 = VDEF <.MEM_2(D)>
  param.f1 = 0;
  # .MEM_4 = VDEF <.MEM_3>
  memcpy (&local, &param, 9);
  # VUSE <.MEM_4>
  D.1743_1 = local.f1;
  if (D.1743_1 != 0)
    goto <bb 3>;
  else
    goto <bb 4>;

<bb 3>:
  # .MEM_5 = VDEF <.MEM_4>
  link_error ();

<bb 4>:
  return;

which shows this is an issue of value-numbering not looking through
memcpy.  SRA obviously does not work here because both vars have their
address taken.  The issue in the summary should have been fixed by the
SRA rewrite.

I'm looking at the VN issue.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |rguenth at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2006-10-24 12:34:46         |2009-09-26 15:30:16
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13954


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [Bug c++/13954] [tree-ssa] SRA does not work for classes that use inheritance with an empty base
       [not found] <bug-13954-1008@http.gcc.gnu.org/bugzilla/>
                   ` (3 preceding siblings ...)
  2009-09-26 15:30 ` rguenth at gcc dot gnu dot org
@ 2010-08-11 12:34 ` rguenth at gcc dot gnu dot org
  4 siblings, 0 replies; 8+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2010-08-11 12:34 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #16 from rguenth at gcc dot gnu dot org  2010-08-11 12:33 -------
We can also expand

  __builtin_memcpy (&local, &param, 9);

to multiple copies based on src/dest alignment and size (similar to
store_by_pieces)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13954


^ permalink raw reply	[flat|nested] 8+ messages in thread

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2011-03-08 15:51 ` [Bug c++/13954] [tree-ssa] SRA does not work for classes that use inheritance with an empty base rguenth at gcc dot gnu.org
2011-03-15 13:39 ` rguenth at gcc dot gnu.org
2011-03-15 13:55 ` rguenth at gcc dot gnu.org
     [not found] <bug-13954-1008@http.gcc.gnu.org/bugzilla/>
2006-03-06 14:42 ` rguenth at gcc dot gnu dot org
2006-10-24 12:34 ` rguenth at gcc dot gnu dot org
2006-10-24 18:31 ` dberlin at gcc dot gnu dot org
2009-09-26 15:30 ` rguenth at gcc dot gnu dot org
2010-08-11 12:34 ` rguenth at gcc dot gnu dot org

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