alt Hacker NewsI've wondered for a long time if we would have been able to make do without protected mode (or hardware protection in general) if user code was verified/compiled at load, e.g. the way the JVM or .NET do it...Could the shift on transistor budget have been used to offset any performance losses?
Microsoft Research had an experimental OS project at one point that does just that with everything running in ring 0 in the same address space:
https://en.wikipedia.org/wiki/Singularity_(operating_system)
Managed code, the properties of their C# derived programming language, static analysis and verification were used rather than hardware exception handling.