Special x86_64 instructions.
Enabling and disabling interrupts
Access to I/O ports
Support for build-in RNGs
Provides functions to read and write segment registers.
Functions to load GDT, IDT, and TSS structures.
Functions to flush the translation lookaside buffer (TLB).
Halts the CPU until the next interrupt arrives.
Gets the current instruction pointer. Note that this is only approximate as it requires a few instructions to execute.