[Bug tree-optimization/112392] `a == nonnegative ? a : abs` -> abs

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112392

--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The trunk branch has been updated by Andrew Pinski <pins...@gcc.gnu.org>:

https://gcc.gnu.org/g:5726de79e2154a16d8a045567d2cfad035f7ed19

commit r15-328-g5726de79e2154a16d8a045567d2cfad035f7ed19
Author: Andrew Pinski <quic_apin...@quicinc.com>
Date:   Mon May 6 23:53:41 2024 -0700

    match: `a CMP nonnegative ? a : ABS<a>` simplified to just `ABS<a>`
[PR112392]

    We can optimize `a == nonnegative ? a : ABS<a>`, `a > nonnegative ? a :
ABS<a>`
    and `a >= nonnegative ? a : ABS<a>` into `ABS<a>`. This allows removal of
    some extra comparison and extra conditional moves in some cases.
    I don't remember where I had found though but it is simple to add so
    let's add it.

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

    Note I have a secondary pattern for the equal case as either a or
nonnegative
    could be used.

            PR tree-optimization/112392

    gcc/ChangeLog:

            * match.pd (`x CMP nonnegative ? x : ABS<x>`): New pattern;
            where CMP is ==, > and >=.
            (`x CMP nonnegative@y ? y : ABS<x>`): New pattern.

    gcc/testsuite/ChangeLog:

            * gcc.dg/tree-ssa/phi-opt-41.c: New test.

    Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com>