riscv-etrace 0.6.2

Decoder and tracer for RISC-V efficient instruction tracing
Documentation 
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// Copyright (C) 2025 FZI Forschungszentrum Informatik
// SPDX-License-Identifier: Apache-2.0
//! Basic decoder tests
use super::*;

use truncate::TruncateNum;

macro_rules! basic_test {
    ($n:ident, $b:literal, $($t:tt)*) => {
        mod $n {
            use super::*;

            #[test]
            fn decode() {
                let mut decoder = Builder::new().decoder($b);
                $(decode_test!(decoder, $t);)*
            }

            #[test]
            fn encode() {
                let mut buffer = alloc::vec::Vec::new();
                buffer.resize($b.len(), 0);
                let mut encoder = Builder::new().encoder(buffer.as_mut());
                $(encode_test!(encoder, $t);)*
                let len = $b.len() - encoder.uncommitted();
                assert_eq!(&buffer[..len], $b.as_ref());
            }
        }
    };
}

macro_rules! decode_test {
    ($d:ident, (bits $i:literal, $v:expr $(, $p:literal)?)) => {
        assert_eq!($d.read_bits($i), Ok($v));
        $(assert_eq!($d.byte_pos(), $p);)?
    };
    ($d:ident, (bit $v:expr $(, $p:literal)?)) => {
        assert_eq!($d.read_bit(), Ok($v));
        $(assert_eq!($d.byte_pos(), $p);)?
    };
    ($d:ident, (diff $v:expr $(, $p:literal)?)) => {
        assert_eq!($d.read_differential_bit(), Ok($v));
        $(assert_eq!($d.byte_pos(), $p);)?
    };
}

macro_rules! encode_test {
    ($e:ident, (bits $i:literal, $v:expr $(, $p:literal)?)) => {
        $e.write_bits($v, $i).expect("Could not write value");
    };
    ($e:ident, (bit $v:expr $(, $p:literal)?)) => {
        $e.write_bit($v).expect("Could not write value");
    };
    ($e:ident, (diff $v:expr $(, $p:literal)?)) => {
        $e.write_differential_bit($v)
            .expect("Could not write value");
    };
}

basic_test!(
    u64_values,
    b"\x5f\x5f\x92\xf1\xf0\xf0\xf0\xf0\xf0\xff\x7f\x01\x00\x00\x00\x00\x00\x00\xf0",
    (bits 6, 0b011111u64, 0)
    (bits 2, 0b01u64, 1)
    (bits 6, 0b011111u64, 1)
    (bits 10, 0b1001001001u64, 3)
    (bits 62, 0x3FFF_F0F0_F0F0_F0F1u64, 10)
    (bits 64, 0xC000_0000_0000_0005u64, 18)
);

basic_test!(
    i64_values,
    b"\xd0",
    (bits 1, 0i64)
    (bits 64, -24i64)
);

basic_test!(
    decompress,
    b"\xff",
    (bits 64, u64::MAX)
    (bits 64, u64::MAX)
    (bits 64, u64::MAX)
    (bits 64, u64::MAX)
);

basic_test!(
    bool_bits,
    b"\x55",
    (bit true)
    (bit false)
    (bit true)
    (bit false)
    (bit true)
    (bit false)
    (bit true)
    (bit false)
);

basic_test!(
    diff_bits,
    b"\x20\xfd",
    (bits 6, 0x20u8)
    (diff true)
    (diff false)
    (diff true)
    (diff true)
    (diff true)

);

basic_test!(
    missing_msb_shift_is_correct,
    b"\x00\xe1",
    (bits 6, 0i64)
    (bits 63, -124i64)
);

macro_rules! truncate_test {
    ($name: ident, $val:expr, $type:ty, $bytes:expr, $expected:expr) => {
        #[test]
        fn $name() {
            let val: $type = $val;
            assert_eq!(val.truncated($bytes), $expected);
        }
    };
}

truncate_test!(truncate_u16, 0xBEEF, u16, 8, 0xEF);
truncate_test!(truncate_u32, 0xFFBEEF, u32, 16, 0xBEEF);
truncate_test!(truncate_i64, 0xBEEF00FF, i64, 0, 0);