Memory order is only preserved on the architectural level, but on the microarchitectural level, all kinds of reordering, optimizations, and speculations are don

Memory order is only preserved on the architectural level, but on the microarchitectural level, all kinds of reordering, optimizations, and speculations are done to maximize the execution thought. Section 7 of the paper I'm linking below could help to understand how these microarchitectural optimizations could break the memory order beyond the rollback point, causing indeed a Machine Clear (Nuke) of the entire pipeline. We have analyzed the entire class of Machine Clear and showed how the different types can create transient execution paths where memory could be transiently leaked. http://download.vusec.net/papers/fpvi-scsb_sec21.pdf http://download.vusec.net/papers/fpvi-scsb_sec21.pdf