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* [Bug tree-optimization/107765] New: missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN
@ 2022-11-19 23:27 pinskia at gcc dot gnu.org
  2022-11-22  8:32 ` [Bug tree-optimization/107765] " rguenth at gcc dot gnu.org
                   ` (5 more replies)
  0 siblings, 6 replies; 7+ messages in thread
From: pinskia at gcc dot gnu.org @ 2022-11-19 23:27 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107765

            Bug ID: 107765
           Summary: missing (int)-(unsigned)int_val to just -int_val if
                    int_val is known not to contain INT_MIN
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

Take:
```
#include <limits.h>

int a(int input)
{
    if (input == INT_MIN) __builtin_unreachable();
    unsigned t = input;
    int tt =  -t;
    return tt == -input;
}
```
We should be able to optimize this at the tree level because we know we don't
invoke undefined behavior.

^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Bug tree-optimization/107765] missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN
  2022-11-19 23:27 [Bug tree-optimization/107765] New: missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN pinskia at gcc dot gnu.org
@ 2022-11-22  8:32 ` rguenth at gcc dot gnu.org
  2023-08-31 18:38 ` pinskia at gcc dot gnu.org
                   ` (4 subsequent siblings)
  5 siblings, 0 replies; 7+ messages in thread
From: rguenth at gcc dot gnu.org @ 2022-11-22  8:32 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107765

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2022-11-22
     Ever confirmed|0                           |1

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed.

^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Bug tree-optimization/107765] missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN
  2022-11-19 23:27 [Bug tree-optimization/107765] New: missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN pinskia at gcc dot gnu.org
  2022-11-22  8:32 ` [Bug tree-optimization/107765] " rguenth at gcc dot gnu.org
@ 2023-08-31 18:38 ` pinskia at gcc dot gnu.org
  2023-09-01  2:27 ` pinskia at gcc dot gnu.org
                   ` (3 subsequent siblings)
  5 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-08-31 18:38 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107765

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |pinskia at gcc dot gnu.org
             Status|NEW                         |ASSIGNED

^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Bug tree-optimization/107765] missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN
  2022-11-19 23:27 [Bug tree-optimization/107765] New: missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN pinskia at gcc dot gnu.org
  2022-11-22  8:32 ` [Bug tree-optimization/107765] " rguenth at gcc dot gnu.org
  2023-08-31 18:38 ` pinskia at gcc dot gnu.org
@ 2023-09-01  2:27 ` pinskia at gcc dot gnu.org
  2023-09-01 16:24 ` pinskia at gcc dot gnu.org
                   ` (2 subsequent siblings)
  5 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-09-01  2:27 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107765

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                URL|                            |https://gcc.gnu.org/piperma
                   |                            |il/gcc-patches/2023-Septemb
                   |                            |er/629018.html
           Keywords|                            |patch

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Patch posted:
https://gcc.gnu.org/pipermail/gcc-patches/2023-September/629018.html

^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Bug tree-optimization/107765] missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN
  2022-11-19 23:27 [Bug tree-optimization/107765] New: missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN pinskia at gcc dot gnu.org
                   ` (2 preceding siblings ...)
  2023-09-01  2:27 ` pinskia at gcc dot gnu.org
@ 2023-09-01 16:24 ` pinskia at gcc dot gnu.org
  2023-09-02  7:03 ` pinskia at gcc dot gnu.org
  2023-09-02  7:29 ` pinskia at gcc dot gnu.org
  5 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-09-01 16:24 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107765

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
So I have decided to solve the original testcase differently.

^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Bug tree-optimization/107765] missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN
  2022-11-19 23:27 [Bug tree-optimization/107765] New: missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN pinskia at gcc dot gnu.org
                   ` (3 preceding siblings ...)
  2023-09-01 16:24 ` pinskia at gcc dot gnu.org
@ 2023-09-02  7:03 ` pinskia at gcc dot gnu.org
  2023-09-02  7:29 ` pinskia at gcc dot gnu.org
  5 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-09-02  7:03 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107765

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                URL|https://gcc.gnu.org/piperma |
                   |il/gcc-patches/2023-Septemb |
                   |er/629018.html              |
           Keywords|patch                       |

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #2)
> Patch posted:
> https://gcc.gnu.org/pipermail/gcc-patches/2023-September/629018.html

What I can do is extend:
https://gcc.gnu.org/pipermail/gcc-patches/2023-September/629156.html

To add the test the first patch has. That will remove the unneeded cast and
all.

^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Bug tree-optimization/107765] missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN
  2022-11-19 23:27 [Bug tree-optimization/107765] New: missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN pinskia at gcc dot gnu.org
                   ` (4 preceding siblings ...)
  2023-09-02  7:03 ` pinskia at gcc dot gnu.org
@ 2023-09-02  7:29 ` pinskia at gcc dot gnu.org
  5 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-09-02  7:29 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107765

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #4)
> (In reply to Andrew Pinski from comment #2)
> > Patch posted:
> > https://gcc.gnu.org/pipermail/gcc-patches/2023-September/629018.html
> 
> What I can do is extend:
> https://gcc.gnu.org/pipermail/gcc-patches/2023-September/629156.html
> 
> To add the test the first patch has. That will remove the unneeded cast and
> all.

Oh and using expr_not_equal_to has the basic code really.

^ permalink raw reply	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2023-09-02  7:29 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
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2022-11-19 23:27 [Bug tree-optimization/107765] New: missing (int)-(unsigned)int_val to just -int_val if int_val is known not to contain INT_MIN pinskia at gcc dot gnu.org
2022-11-22  8:32 ` [Bug tree-optimization/107765] " rguenth at gcc dot gnu.org
2023-08-31 18:38 ` pinskia at gcc dot gnu.org
2023-09-01  2:27 ` pinskia at gcc dot gnu.org
2023-09-01 16:24 ` pinskia at gcc dot gnu.org
2023-09-02  7:03 ` pinskia at gcc dot gnu.org
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