isla-lib 0.2.0

Isla is a symbolic execution engine for Sail instruction set architecture specifications. This crate implements the core symbolic execution engine as a library.
Documentation 
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// BSD 2-Clause License
//
// Copyright (c) 2019, 2020 Alasdair Armstrong
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// 1. Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

use crate::bitvector::BV;
use crate::ir::*;
use crate::log;
use crate::simplify::EventReferences;
use crate::smt::{Solver, Sym};
use crate::zencode;

/// Logs the taint info for a symbol, the set of registers that it's
/// value is derived from, and whether the value is derived from a
/// memory access. Note that computing this is relatively expensive,
/// so use of this should usually be done only in the event of an
/// error or guarded behind a flag.
///
/// This function can be called from a context without a SharedState
/// reference, so this argument is optional.
pub fn taint_info<B: BV>(log_type: u32, sym: Sym, shared_state: Option<&SharedState<B>>, solver: &Solver<B>) {
    let events = solver.trace().to_vec();
    let references = EventReferences::from_events(&events);

    let (taints, memory) = references.taints(sym, &events);
    let taints: Vec<String> = taints
        .iter()
        .map(|(reg, _)| {
            if let Some(shared_state) = shared_state {
                zencode::decode(shared_state.symtab.to_str(*reg))
            } else {
                format!("{:?}", reg)
            }
        })
        .collect();
    let memory = if memory { ", MEMORY" } else { "" };

    log!(log_type, &format!("Symbol {} taints: {:?}{}", sym, taints, memory))
}

pub fn args_info<B: BV>(tid: usize, args: &[Val<B>], shared_state: &SharedState<B>, solver: &Solver<B>) {
    let events = solver.trace().to_vec();
    let references = EventReferences::from_events(&events);

    for arg in args {
        for sym in arg.symbolic_variables() {
            let (taints, memory) = references.taints(sym, &events);
            let taints: Vec<String> =
                taints.iter().map(|(reg, _)| zencode::decode(shared_state.symtab.to_str(*reg))).collect();
            let memory = if memory { ", MEMORY" } else { "" };
            log_from!(tid, log::PROBE, &format!("Symbol {} taints: {:?}{}", sym, taints, memory))
        }
    }
}

pub fn call_info<B: BV>(f: Name, args: &[Val<B>], symtab: &Symtab) -> String {
    let symbol = zencode::decode(symtab.to_str(f));
    format!("Calling {}({:?})", symbol, args.iter().map(|arg| arg.to_string(symtab)).collect::<Vec<String>>())
}