Panics found by fuzzing

[WIZeaz]

Hi, I am fuzzing xorfilter-rs with afl.rs, and I have found some panics. The version I test is 0.5.1. I list the code snippets below, and hope you can check whether these panics are bugs. All code snippets can be run directly.

These cases are panicked at 'attempt to add with overflow'

let mut _local0: xorfilter::Fuse8::<xorfilter::NoHash> = xorfilter::Fuse8::<xorfilter::NoHash>::with_hasher(4177066232, xorfilter::NoHash{});

xorfilter::Fuse16::<xorfilter::NoHash>::with_hasher(4177066232, xorfilter::NoHash{});

thread 'main' panicked at 'attempt to add with overflow', /home/jjf/Fuzzing-Target-Generator/experiments/xorfilter/src/fuse8.rs:202:23
stack backtrace:
   0: rust_begin_unwind
   1: core::panicking::panic_fmt
   2: core::panicking::panic
   3: xorfilter::fuse8::Fuse8<H>::with_hasher
   4: replay_xorfilter19::test_function19
             at ./fuzz_target/build/replay_xorfilter19/src/main.rs:28:62
   5: replay_xorfilter19::main
             at ./fuzz_target/build/replay_xorfilter19/src/main.rs:64:5
   6: core::ops::function::FnOnce::call_once
             at /home/jjf/Fuzzing-Target-Generator/library/core/src/ops/function.rs:251:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

This case is panicked at 'index out of bounds: the len is 0 but the index is 0'

    let _local0: xorfilter::Xor8::<xorfilter::NoHash> = xorfilter::Xor8::<xorfilter::NoHash>::with_hasher(xorfilter::NoHash{});
    let _local1_param0_helper1 = &(_local0);
    let _: bool = xorfilter::Xor8::<xorfilter::NoHash>::contains_key(_local1_param0_helper1, 14355285626356002360);

thread 'main' panicked at 'index out of bounds: the len is 0 but the index is 0', /home/jjf/Fuzzing-Target-Generator/experiments/xorfilter/src/xor8.rs:422:15
stack backtrace:
   0: rust_begin_unwind
   1: core::panicking::panic_fmt
   2: core::panicking::panic_bounds_check
   3: <usize as core::slice::index::SliceIndex<[T]>>::index
             at /home/jjf/Fuzzing-Target-Generator/library/core/src/slice/index.rs:259:10
   4: core::slice::index::<impl core::ops::index::Index<I> for [T]>::index
             at /home/jjf/Fuzzing-Target-Generator/library/core/src/slice/index.rs:18:9
   5: <alloc::vec::Vec<T,A> as core::ops::index::Index<I>>::index
             at /home/jjf/Fuzzing-Target-Generator/library/alloc/src/vec/mod.rs:2736:9
   6: xorfilter::xor8::Xor8<H>::contains_key
             at ./src/xor8.rs:422:15
   7: replay_xorfilter35::test_function35
             at ./fuzz_target/build/replay_xorfilter35/src/main.rs:30:19
   8: replay_xorfilter35::main
             at ./fuzz_target/build/replay_xorfilter35/src/main.rs:62:5
   9: core::ops::function::FnOnce::call_once
             at /home/jjf/Fuzzing-Target-Generator/library/core/src/ops/function.rs:251:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.