Architectural Comparisons
This table compares important factors for a decision in which ISA to use and support
| Feature/Need | RISC-V | MIPS | OpenPOWER | OpenRISC | |
|---|---|---|---|---|---|
| Open | NO (1) | NO (2) | WIP (3) | Yes | |
| Libre-friendly | NO (1) | unknown | Yes | Yes | |
| Trademarked | Yes | Yes | Yes | No | |
| Extensible | NO (4) | unknown | Potentially (5) | Yes | |
| gcc | Yes | Yes | Yes | Yes | |
| llvm | Yes | Yes | Yes | Yes | |
| llvm upstream | Yes | Yes | Yes | No | |
| distros (debian) | Yes | Yes | Yes | No | |
| distros (ubuntu) | No | No | Yes | No | |
| distros (fedora) | Yes | Yes | Yes | No | |
| buildroot | Yes | Yes | Yes | Yes | |
| linux kernel | Yes | Yes | Yes | Yes | |
| 64-bit linux | Yes | Yes | Yes | No | |
| virtualizable | Yes | unknown | Yes | No (6) | |
| 64-bit asics | many | many | many | none | |
| sw community size | large | medium | very large | tiny (7) | |
| little-endian asics | Yes | Yes | Yes | No | |
| Java (OpenJDK) | no JIT | unknown | Yes | No | |
| Java (Android) | No? | Yes | No | No | |
| V8 node.js/chromium | no JIT | Yes | Yes | No | |
| PyPy | No | No | Yes | No | |
| Mono (.net) | No? | 32-bit | Yes | No | |
| Spidermonkey (Firefox JS) | no JIT | Yes (JIT Unsupported) | no JIT | No | |
- (1) too numerous reasons to count, for well over 4 years.
- (2) efforts to be "open" have stalled, website non-functional
- (3) OpenPower Foundation making a huge effort, really appreciated
- (4) repeated in-good-faith requests for participation and inclusion in extending RISC-V have met with stone-cold silence for over 18 months, in direct violation of Trademark Law's clear-cut responsibilities.
- (5) provisionally and in principle: yes. however as of 2019jan21 this is yet to be tested and an agreement reached.
- (6) no mentions of virtualization found in spec
- (7) dozens to hundreds of people, several companies