[Bug tree-optimization/78317] "if (x & constant) z |= constant" should not be rendered with jumps and conditional moves

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78317

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
The issue is probably that we very early end up with

   return x & 0x10 ? 0x10 : 0;

and uncprop transforms that only to

   return x & 0x10 ? 0x10 : x;

rather than

   return x & 0x10 ? x : x;