fuzz/fuzz_targets/fresh-decode.rs


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//! decoding into a pre-existing instruction should not result in different outcomes compared to
//! decoding into a fresh instruction. if decoding succeeds, both outcomes should be equal.

#![no_main]
use libfuzzer_sys::fuzz_target;

use yaxpeax_arch::Decoder;

fuzz_target!(|data: &[u8]| {
    let decoder = yaxpeax_hexagon::InstDecoder::default();

    let mut reused_inst = yaxpeax_hexagon::InstructionPacket::default();

    let mut words = yaxpeax_arch::U8Reader::new(data);
    // test decoding, may be ok or not, but should not panic
    if let Ok(()) = decoder.decode_into(&mut reused_inst, &mut words) {
        let mut words = yaxpeax_arch::U8Reader::new(data);
        let fresh_inst = decoder.decode(&mut words).expect("decoded before, can decode again");
        assert_eq!(reused_inst, fresh_inst);

        let s = reused_inst.to_string();
        assert!(!s.contains("BUG"));
        assert!(!s.contains("<invalid decode>"));
    }
});