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Class 02 · KP 06 / 23

Special Registers: RIP and RFLAGS

RIP — Instruction Pointer

Holds the address of the next instruction to execute.

Cannot be written directly; changed by jmp, call, ret.

x86-64 supports RIP-relative addressing (position-independent code).

RFLAGS — Status Flags (set by arithmetic/compare)

Key Takeaway

Conditional jumps do not test values — they test flags left behind by the previous cmp or test.