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* [Bug middle-end/38856] loop iv detection failure
       [not found] <bug-38856-4@http.gcc.gnu.org/bugzilla/>
@ 2010-12-01 20:49 ` slarin at codeaurora dot org
  2021-11-28  4:31 ` pinskia at gcc dot gnu.org
  1 sibling, 0 replies; 8+ messages in thread
From: slarin at codeaurora dot org @ 2010-12-01 20:49 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38856

Sergei Larin <slarin at codeaurora dot org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |slarin at codeaurora dot
                   |                            |org

--- Comment #8 from Sergei Larin <slarin at codeaurora dot org> 2010-12-01 20:48:47 UTC ---

Hello, 

  This has not been touched in a while, nevertheless the issue still exist with
4.5.1


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

* [Bug middle-end/38856] loop iv detection failure
       [not found] <bug-38856-4@http.gcc.gnu.org/bugzilla/>
  2010-12-01 20:49 ` [Bug middle-end/38856] loop iv detection failure slarin at codeaurora dot org
@ 2021-11-28  4:31 ` pinskia at gcc dot gnu.org
  1 sibling, 0 replies; 8+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-11-28  4:31 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=38856

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |

--- Comment #9 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I think the original issue has been fixed since GCC 4.5.0 or so.

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

* [Bug middle-end/38856] loop iv detection failure
  2009-01-15 18:24 [Bug c/38856] New: loop iv detection failure, SSA autoincrement sergei_lus at yahoo dot com
                   ` (3 preceding siblings ...)
  2009-01-16 11:46 ` pinskia at gmail dot com
@ 2009-01-16 18:53 ` pinskia at gcc dot gnu dot org
  4 siblings, 0 replies; 8+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2009-01-16 18:53 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #7 from pinskia at gcc dot gnu dot org  2009-01-16 18:53 -------
Here is a testcase where IV can be found but we end up with two copies of the
same register in the loop:
int f(unsigned long s, unsigned long *c)
{
  long j;
  for(j = 0;j < s; j++)
    {
      c[j]=j;
    }
}

Which is basically the same issue.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38856


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

* Re: [Bug middle-end/38856] loop iv detection failure
  2009-01-16  9:57 ` rguenth at gcc dot gnu dot org
@ 2009-01-16 11:46   ` Andrew Thomas Pinski
  0 siblings, 0 replies; 8+ messages in thread
From: Andrew Thomas Pinski @ 2009-01-16 11:46 UTC (permalink / raw)
  To: gcc-bugzilla; +Cc: gcc-bugs



Sent from my iPhone

On Jan 16, 2009, at 1:57 AM, "rguenth at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org 
 > wrote:

>
>
> ------- Comment #5 from rguenth at gcc dot gnu dot org  2009-01-16  
> 09:57 -------
> I think this boils down to the usual POINTER_PLUS fallout.

It failed in 4.1 also so nope :).

>
>
>
> -- 
>
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38856
>


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

* [Bug middle-end/38856] loop iv detection failure
  2009-01-15 18:24 [Bug c/38856] New: loop iv detection failure, SSA autoincrement sergei_lus at yahoo dot com
                   ` (2 preceding siblings ...)
  2009-01-16  9:57 ` rguenth at gcc dot gnu dot org
@ 2009-01-16 11:46 ` pinskia at gmail dot com
  2009-01-16 18:53 ` pinskia at gcc dot gnu dot org
  4 siblings, 0 replies; 8+ messages in thread
From: pinskia at gmail dot com @ 2009-01-16 11:46 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #6 from pinskia at gmail dot com  2009-01-16 11:46 -------
Subject: Re:  loop iv detection failure



Sent from my iPhone

On Jan 16, 2009, at 1:57 AM, "rguenth at gcc dot gnu dot org"
<gcc-bugzilla@gcc.gnu.org 
 > wrote:

>
>
> ------- Comment #5 from rguenth at gcc dot gnu dot org  2009-01-16  
> 09:57 -------
> I think this boils down to the usual POINTER_PLUS fallout.

It failed in 4.1 also so nope :).

>
>
>
> -- 
>
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38856
>


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38856


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

* [Bug middle-end/38856] loop iv detection failure
  2009-01-15 18:24 [Bug c/38856] New: loop iv detection failure, SSA autoincrement sergei_lus at yahoo dot com
  2009-01-15 21:13 ` [Bug middle-end/38856] loop iv detection failure pinskia at gcc dot gnu dot org
  2009-01-15 21:17 ` pinskia at gcc dot gnu dot org
@ 2009-01-16  9:57 ` rguenth at gcc dot gnu dot org
  2009-01-16 11:46   ` Andrew Thomas Pinski
  2009-01-16 11:46 ` pinskia at gmail dot com
  2009-01-16 18:53 ` pinskia at gcc dot gnu dot org
  4 siblings, 1 reply; 8+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2009-01-16  9:57 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #5 from rguenth at gcc dot gnu dot org  2009-01-16 09:57 -------
I think this boils down to the usual POINTER_PLUS fallout.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38856


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

* [Bug middle-end/38856] loop iv detection failure
  2009-01-15 18:24 [Bug c/38856] New: loop iv detection failure, SSA autoincrement sergei_lus at yahoo dot com
  2009-01-15 21:13 ` [Bug middle-end/38856] loop iv detection failure pinskia at gcc dot gnu dot org
@ 2009-01-15 21:17 ` pinskia at gcc dot gnu dot org
  2009-01-16  9:57 ` rguenth at gcc dot gnu dot org
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 8+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2009-01-15 21:17 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #4 from pinskia at gcc dot gnu dot org  2009-01-15 21:17 -------
Here is a good testcase:
void
VecADD(
    int *In1,
    int *In2,
    int *Out,
    unsigned int samples
){
  int i;
  for (i = 0; i < samples; i++) {
    Out[i] = In1[i];
  }
}

This testcase should be vectorized with -maltivec -O3 on PowerPC but is not
while it is with -m64.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2009-01-15 21:17:17
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38856


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

* [Bug middle-end/38856] loop iv detection failure
  2009-01-15 18:24 [Bug c/38856] New: loop iv detection failure, SSA autoincrement sergei_lus at yahoo dot com
@ 2009-01-15 21:13 ` pinskia at gcc dot gnu dot org
  2009-01-15 21:17 ` pinskia at gcc dot gnu dot org
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 8+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2009-01-15 21:13 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #3 from pinskia at gcc dot gnu dot org  2009-01-15 21:13 -------
This bug is a bit funny, autoincrement is not the issue, just the detecting of
the induction variable's limits correctly.  For an example I noticed that if I
compile this on a LP64 target, the induction variable is found correctly.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|c                           |middle-end
           Keywords|                            |missed-optimization
            Summary|loop iv detection failure,  |loop iv detection failure
                   |SSA autoincrement           |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38856


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

end of thread, other threads:[~2021-11-28  4:31 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
     [not found] <bug-38856-4@http.gcc.gnu.org/bugzilla/>
2010-12-01 20:49 ` [Bug middle-end/38856] loop iv detection failure slarin at codeaurora dot org
2021-11-28  4:31 ` pinskia at gcc dot gnu.org
2009-01-15 18:24 [Bug c/38856] New: loop iv detection failure, SSA autoincrement sergei_lus at yahoo dot com
2009-01-15 21:13 ` [Bug middle-end/38856] loop iv detection failure pinskia at gcc dot gnu dot org
2009-01-15 21:17 ` pinskia at gcc dot gnu dot org
2009-01-16  9:57 ` rguenth at gcc dot gnu dot org
2009-01-16 11:46   ` Andrew Thomas Pinski
2009-01-16 11:46 ` pinskia at gmail dot com
2009-01-16 18:53 ` pinskia at gcc dot gnu dot org

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