I agree with what you're saying around the Mill and dataflow in a sense, but feel like we disagree in the details. The issue with Spectre, etc. is that data of

I agree with what you're saying around the Mill and dataflow in a sense, but feel like we disagree in the details. The issue with Spectre, etc. is that data of different trust levels are comingled in a single address space. We want the processor to speculate on some data, but not others and we don't tell it how to tell the difference. What's going to save us isn't dependency information or static scheduling, but more fine grained permissions around the data accessible at a single time. IMO we need to bring back segmentation hardware. Not the x86 version of segmentation (there's not a feature that x86 wasn't able to make twice as complicated as it needed to be while only giving you half the use cases), but the cleaner object capability on top of paging hardware versions of segmentation. That solves the really rough Spectre cases like even NetSpectre where you can slurp out kernel state remotely from untrusted network packets. Just stick them in a "this memory is untrusted" segment. From there the CPU's dynamic dataflow optimizations can include speculation where memory is marked as trusted.