Rysk Core

RISCV decoding and execution primitives. All you need to implement your own virtual RISCV machine.

Virtual Machine

If you are looking for a working virtual machine you want Rysk. This is a library for building RISCV virtual machines.

Usage

First, add a dependency to your Cargo.toml: toml [dependencies] rysk-core = "0.0.2"

Then in your project, ```rust // Implement a memory management unit impl rysk_core::Mmu/> for YourMmu { / ... */ }

// Run your system
fn main() {
    let mmu = YourMmu::new();
    let core = rysk_core::Core::</* Register Size */>::new(/* PC initial address */);

    loop {
        // fetch, then decode & execute
        core.execute(mmu.fetch_instruction(core.pc), &mut mmu).expect("Unable to decode instruction");
    }
}

```

Goals

Current Goals - [ ] Compatability with all platforms std supports - [ ] Support for RV32IMA and RV64IMA - [x] Dependency-free - [ ] Support for the Privileged ISA

Future Goals - [ ] Performance - [ ] Support for all base extensions - [ ] Debugging tools

Compliance

Note: This list does not account for errors and/or bugs in the implementation. Perfect compliance is not guaranteed

If an instruction does not behave as specified please leave an issue

| Extension | Support | | :-----------: | :-----: | | RV32I | Partial | | RV32E | None* | | RV64I | Full | | RV128I | None | | Zifencei | None | | Zicsr | Partial | | N | None | | M | None | | A | None | | F | None | | D | None | | Q | None | | C | None | | G | Partial | | LBJTPV | N/A | | Zam | N/A | | Ztso | Always |

*Support for the embedded extension is low priority. Const-generics will make implementing this feature much cleaner and as such supporting RV32E is not planned until const-generics land in stable Rust.

Privilege Levels

Extensions

Most extensions are enabled through cargo features.

The base extension (RV32I, RV64I or RV128I) is set through the generic register type used. MXLEN is a set at compile time and therefore cannot be changed by RISCV programs (ie. misa[MXLEN] is read-only).