LNSym: Native Code Symbolic Simulator in Lean

LNSym is a symbolic simulator for Armv8 machine-code programs.

Please see the LICENSE file for LNSym's licensing and CONTRIBUTING.md for external contribution guidelines.

Prerequisites

1. Install Z3, recommended version 4.11.2, and make sure that it is in your path.

2. Install Lean4 and your preferred editor's plug-in on your machine by following these instructions.

Build Instructions

Run make at the top-level of LNSym to fetch the Lean4 dependencies, build this library (including the proofs), and run conformance testing. Note that if you are not on an Aarch64 machine, conformance testing will be skipped.

The default make command corresponds to the following invocation:

make all VERBOSE=--verbose NUM_TESTS=20

Other Makefile targets

clean: remove build outputs.

clean_all: clean plus remove Lean dependencies.

specs: [run under all] builds only the specifications of native-code programs of interest.

proofs: [run under all] builds only the proofs.

tests: [run under all] builds concrete tests.

cosim: [run under all] perform conformance testing.

Makefile variables that can be passed in at the command line

VERBOSE: Verbose mode; prints disassembly of the instructions being tested. Default: on.

NUM_TESTS: Number of random tests/instruction class. Default: 20.

Directory Overview

• Arm: Formalization of the Armv8 Aarch64 ISA
• Specs: Specifications of algorithms of interest
• Proofs: Proofs of Arm native-code programs
• Tests: Concrete tests of Arm native-code programs