[Bug tree-optimization/111957] New: `a ? abs(a) : 0` is not simplified to just abs(a)

[Bug tree-optimization/111957] New: `a ? abs(a) : 0` is not simplified to just abs(a)

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111957

            Bug ID: 111957
           Summary: `a ? abs(a) : 0` is not simplified to just abs(a)
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
          Assignee: pinskia at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

Take:
```
int f(int a)
{
  if (a)
  return a > 0 ? a : -a;
  return 0;
}
```

This should just simplify to ` return a > 0 ? a : -a;` or rather `return
abs(a);`

[Bug tree-optimization/111957] `a ? abs(a) : 0` is not simplified to just abs(a)

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111957

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2023-10-24
             Status|UNCONFIRMED                 |ASSIGNED
     Ever confirmed|0                           |1

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
.

[Bug tree-optimization/111957] `a ? abs(a) : 0` is not simplified to just abs(a)

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111957

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
We already have patterns for -a and ~a even:
/* X != C1 ? -X : C2 simplifies to -X when -C1 == C2.  */
/* X != C1 ? ~X : C2 simplifies to ~X when ~C1 == C2.  */


I will add one to handle abs too.

[Bug tree-optimization/111957] `a ? abs(a) : 0` is not simplified to just abs(a)

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111957

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Created attachment 56196
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=56196&action=edit
patch which I am testing

[Bug tree-optimization/111957] `a ? abs(a) : 0` is not simplified to just abs(a)

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111957

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                URL|                            |https://gcc.gnu.org/piperma
                   |                            |il/gcc-patches/2023-October
                   |                            |/634204.html
           Keywords|                            |patch

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Patch posted:
https://gcc.gnu.org/pipermail/gcc-patches/2023-October/634204.html

[Bug tree-optimization/111957] `a ? abs(a) : 0` is not simplified to just abs(a)

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111957

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The trunk branch has been updated by Andrew Pinski <pinskia@gcc.gnu.org>:

https://gcc.gnu.org/g:662655e22dddf5392d9aa67fce45beee980e5454

commit r14-4955-g662655e22dddf5392d9aa67fce45beee980e5454
Author: Andrew Pinski <pinskia@gmail.com>
Date:   Tue Oct 24 23:13:18 2023 +0000

    match: Simplify `a != C1 ? abs(a) : C2` when C2 == abs(C1) [PR111957]

    This adds a match pattern for `a != C1 ? abs(a) : C2` which gets simplified
    to `abs(a)`. if C1 was originally *_MIN then change it over to use absu
instead
    of abs.

    Bootstrapped and tested on x86_64-linux-gnu with no regressions.

            PR tree-optimization/111957

    gcc/ChangeLog:

            * match.pd (`a != C1 ? abs(a) : C2`): New pattern.

    gcc/testsuite/ChangeLog:

            * gcc.dg/tree-ssa/phi-opt-40.c: New test.

[Bug tree-optimization/111957] `a ? abs(a) : 0` is not simplified to just abs(a)

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111957

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|ASSIGNED                    |RESOLVED
   Target Milestone|---                         |14.0

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
fixed.