[Bug tree-optimization/98954] New: Failure to optimize left shift+and pattern

[gabravier at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98954

            Bug ID: 98954
           Summary: Failure to optimize left shift+and pattern
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

bool f(uint8_t m)
{
    return !((m << 1) & 0xFF);
}

This can be optimized to `return !(m & 0x7F);`. This transformation is done by
LLVM, but not by GCC.