Comment by gpderetta

Maybe, but not there yet: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110899

In the meantime some inline assembly macro trickery might help.

edit: code duplication can also be obviated by templating your op function with a fast/slow parameter, with the fast variant tail-calling the slow variant when it cannot perform the fast path, while guarding the slow code via the compile time parameter. The downside is yet more code obfuscation of course.