riscVM: High-Performance RISC-V zkVM

riscVM is a specialized implementation of the RISC-V RV32I Instruction Set Architecture (ISA) designed from the ground up for Zero-Knowledge (ZK) provability. It features a high-fidelity Go-based emulator, a constraint-optimized ZK circuit backend using gnark, and a sleek, reactive web interface for real-time proof inspection.

System Architecture

The project is structured into four distinct layers:

1. Execution Engine (/vm): A robust RV32I emulator that handles the Fetch-Decode-Execute cycle. It includes a custom ELF loader and a Linux-compatible syscall interface.
2. Constraint System (/zk): An arithmetized representation of the RISC-V state transition. Every instruction is decomposed into a set of R1CS constraints that verify the integrity of the execution.
3. WASM Bridge (/cmd/wasm): A high-throughput bridge that exposes the VM's internal state and ZK prover to the browser environment.
4. Verification Dashboard (/web): A minimalist frontend that visualizes the execution trace and displays cryptographic "Proof Certificates" for every instruction step.

Technical Specifications

Feature	Specification
ISA Support	RV32I Base Integer (excluding Fences/CSRs)
Memory Model	16MB Byte-addressable with bounds checking
ZK Backend	gnark (Groth16 / PLONK)
Field	BN254 (alt_bn128)
Host Language	Go 1.25+
Target	WASM / Native CLI

Directory Structure

• main.go: The CLI entry point for native RISC-V execution.
• vm/: The core virtual machine.
  • cpu.go: State management (PC, 32 registers, status).
  • decode.go: RISC-V instruction parser using bitmasking.
  • instruction.go: Concrete implementations for 40+ instructions.
  • trace.go: Captures the execution history required for ZK witness generation.
• zk/: The Zero-Knowledge proving system.
  • circuit.go: The gnark circuit defining the transition function.
  • prover.go: Witness generation logic and proof orchestration.
• cmd/wasm/: JS-Go interop layer.
• web/: Assets for the browser-based dashboard.

Quick Start

Native CLI

Compile and run a RISC-V ELF binary:

go build -o riscvm .
./riscvm examples/complexity.elf

Web Interface

1. Build WASM:

   GOOS=js GOARCH=wasm go build -o web/riscvm.wasm ./cmd/wasm

2. Serve:

   cd web && python3 -m http.server 8080

Development & Testing

The project maintains a rigorous testing suite for both the VM and the ZK circuits.

# Test VM instruction accuracy
go test ./vm/...

# Test ZK circuit constraints
go test -v ./zk

Vision & Roadmap

riscVM aims to be the most accessible educational and production-ready zkVM.

• Phase 1: Core RV32I Emulation & Tracing.
• Phase 2: Single-step ZK Proofs for Arithmetic & Control Flow.
• Phase 3: High-fidelity Web Visualization.
• Phase 4: Memory Log constraints (Permutation Arguments).
• Phase 5: Recursive proof aggregation for full-trace verification.