[Bug tree-optimization/94785] New: Failure to detect abs pattern using multiplication

[gabravier at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94785

            Bug ID: 94785
           Summary: Failure to detect abs pattern using multiplication
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

unsigned r(int v)
{
    return (1 | -(v < 0)) * v;
}

`r` is equivalent to `abs(v)`. GCC does not make the transformation to an
`abs`.

Example of the optimization not being done : https://godbolt.org/z/Rw-hBt