Look up the precise behavior of a RISC-V instruction when writing or debugging a compiler backend.
Understand the privileged architecture rules when porting an operating system or hypervisor to RISC-V.
Build the specification PDFs locally using Docker to get the latest draft before an official release.
Check the profile definitions to verify which instruction extensions a chip must support to claim compliance.
Building PDFs locally requires Docker, pre-built PDFs are available on the GitHub releases page.
This repository holds the source files for the official RISC-V Instruction Set Manual. RISC-V is an open standard for how processors understand and execute instructions, and this manual is the formal document that defines those rules. Chip designers, compiler authors, and operating system developers use it as the authoritative reference for what a RISC-V processor is required to do. The manual is split into three volumes. Volume I covers the unprivileged architecture, which describes the instructions any RISC-V program can use. Volume II covers the privileged architecture, which describes the rules for operating systems and hypervisors that manage hardware resources. Volume III covers profiles, which are named combinations of features that define standard configurations a chip can advertise support for. The files in this repository are the original source documents written in a markup format, not polished PDFs. The official finished specifications are published on the RISC-V International website. Pre-built PDFs of the latest drafts are available on the GitHub releases page, and HTML snapshots of the most recent commit can be viewed directly in a browser. If you want to build the documents yourself, the recommended method uses a Docker image maintained by the RISC-V project, which handles all the required formatting tools automatically. The repository also supports local builds and automated GitHub Actions builds for those who prefer different workflows. The content is licensed under Creative Commons Attribution 4.0, which means anyone can share and adapt it as long as they credit the original source.
← riscv on gitmyhub — every repo by this author, as a profile.
Verify against the repo before relying on details.