On Wed, Nov 20, 2024 at 04:07:38PM -0800, Andrii Nakryiko wrote: > USDTs are meant to be "transparent" to the surrounding code and they > don't mark any clobbered registers. Technically it could be added, but > I'm not a fan of this. Sure. Anyway, another thing to consider is FRED, will all of this still matter once that lands? If FRED gets us INT3 performance close to what SYSCALL has, then all this work will go unused.