Crate ab_riscv_interpreter 

Composable and generic RISC-V interpreter.

This interpreter is designed to work with abstractions from ab-riscv-primitives crate and is similarly composable with a powerful macro system and trait abstractions over handling of memory, syscalls, etc.

The immediate needs dictate the current set of available instructions and extensions. Consider contributing if you need something not yet available.

ab-riscv-act4-runner crate in the repository contains a complementary RISC-V Architectural Certification Tests runner for https://github.com/riscv-non-isa/riscv-arch-test that ensures correct implementation.

Does not require a standard library (no_std) or an allocator.

Supported ISA variants and extensions

ISA variants:

• RV32I (version 2.1)
• RV32E (version 2.0)
• RV64I (version 2.1)
• RV64E (version 2.0)

Extensions:

• M (version 2.0)
• B (version 1.0.0)
• Zba (version 1.0.0)
• Zbb (version 1.0.0)
• Zbc (version 1.0.0)
• Zbkc (version 1.0.0)
• Zbs (version 1.0.0)
• Zknh (version 1.0.0)
• Zicsr (version 2.0)
• (experimental) Zve32x (version 1.0.0)
• (experimental) Zve64x (version 1.0.0)
• (experimental) Zvl*b (version 1.0.0), where * is anything allowed by the specification

All extensions except experimental pass all relevant RISC-V Architectural Certification Tests (ACTs) using the ACT4 framework.

Any permutation of compatible extensions is supported.

Experimental extensions are known to have bugs and need more work. They are not tested against ACTs yet.

Modules

rv32

Part of the interpreter responsible for RISC-V RV32 base instruction set

rv64

Part of the interpreter responsible for RISC-V RV64 base instruction set

v

V extension

zicsr

Zicsr extension

Structs

BasicInstructionFetcher

Basic instruction fetcher implementation

CustomErrorPlaceholder

Placeholder for custom errors in ExecutionError

InterpreterState

Base interpreter state

Enums

CsrError

CSR error

ExecutionError

Execution errors

FetchInstructionResult

Result of InstructionFetcher::fetch_instruction() call

ProgramCounterError

Program counter errors

VirtualMemoryError

Errors for VirtualMemory

Traits

BasicInt

Basic integer types that can be read and written to/from memory freely

Csrs

CSRs (Control and Status Registers)

ExecutableInstruction

Trait for executable instructions.

InstructionFetcher

Generic instruction fetcher

ProgramCounter

Generic program counter

SystemInstructionHandler

Custom handler for system instructions ecall and ebreak

VirtualMemory

Virtual memory interface