The FLAGS Register and Status Bits
Explore the EFLAGS/RFLAGS register: how arithmetic and comparison instructions set status flags like ZF, CF, SF, and OF that drive every conditional decision.
What is the FLAGS Register?
The FLAGS register (EFLAGS in 32-bit, RFLAGS in 64-bit) is a special register where individual bits record the result of the most recent operation.
Why Flags Matter
The CPU has no boolean type. Instead, instructions set flag bits, and conditional jumps read them. Flags are the glue between arithmetic and control flow.
All lessons in this course
- x86 Registers Demystified
- Memory Addressing Modes
- Data Representation and Types
- The FLAGS Register and Status Bits