#extensions

RISC-V

Nov 4, 2026

RISC-V Overview: The Spec, ISA Names, and What Extensions Do to Code

Part 1 of the RISC-V series. Covers the design principles of a modular ISA, how the specification is split into two volumes (Unprivileged and Privileged), and how to read names like rv64gc, then compiles the same C functions under different extension combinations and measures the code size dropping from 972 bytes to 402 bytes.