[Bug tree-optimization/95922] New: Failure to optimize `((b ^ a) & c) ^ a` to `(a & ~c) | (b & c)` the right way on architectures with andnot

[gabravier at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95922

            Bug ID: 95922
           Summary: Failure to optimize `((b ^ a) & c) ^ a` to `(a & ~c) |
                    (b & c)` the right way on architectures with andnot
           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: ---

int f(int a, int b, int c)
{
    return ((b ^ a) & c) ^ a;
}

This can be optimized to `return (a & ~c) | (b & c);` on processors that have
andnot instructions (at least according to LLVM, which does this transformation
on x86 with -mbmi).