Available on x86 or x86-64 only.
Architecture-specific primitives common to 32-bit and 64-bit x86 processors.
- Processor feature detection with CPUID.
- Support for managing interrupts.
- Access to I/O space
- Support for virtual memory paging.
- Support for protected mode operation.
CR0: System control register with flags affecting protection, paging, and FPU behavior.
CR4: Miscellaneous system control flags.
XCR0: System control flags that indicate OS support for context management for various registers with the
RFLAGS: General flags, including control, status, and basic system flags.