vm 0.1.0

A general purpose virtual machine
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138

use std::collections::BTreeMap;

#[derive(Debug)]
/// Encapsulated abstraction for memory values.
enum MemoryCell {
    ByteArray(Box<[u8]>),
}

#[derive(Debug, Default)]
pub struct Memory {
    cells: BTreeMap<usize, MemoryCell>,
}

/// Assigns a given type value to the memory cell at the given index.
/// Retrieves a given type value from the memory cell at the given index.
macro_rules! primitive_impl {
    ($put_fn:ident, $get_fn:ident, $type:ty) => {
        pub fn $put_fn(&mut self, index: usize, value: $type) {
            self.cells
                .insert(index, MemoryCell::ByteArray(value.to_le_bytes().into()));
        }

        #[must_use]
        pub fn $get_fn(&self, index: usize) -> $type {
            match &self.cells[&index] {
                MemoryCell::ByteArray(value) => {
                    <$type>::from_le_bytes(value[..size_of::<$type>()].try_into().unwrap())
                }
            }
        }
    };
}

impl Memory {
    #[must_use]
    /// Constructs a new [`MemoryCell`].
    pub fn new() -> Self {
        Self::default()
    }

    primitive_impl!(put_u8, get_u8, u8);
    primitive_impl!(put_u16, get_u16, u16);
    primitive_impl!(put_u32, get_u32, u32);
    primitive_impl!(put_u64, get_u64, u64);

    primitive_impl!(put_i8, get_i8, i8);
    primitive_impl!(put_i16, get_i16, i16);
    primitive_impl!(put_i32, get_i32, i32);
    primitive_impl!(put_i64, get_i64, i64);

    primitive_impl!(put_f32, get_f32, f32);
    primitive_impl!(put_f64, get_f64, f64);
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_u8() {
        let mut memory = Memory::new();
        memory.put_u8(0, 0x01);

        assert_eq!(memory.get_u8(0), 0x01);
    }

    #[test]
    fn test_u16() {
        let mut memory = Memory::new();
        memory.put_u16(0, 0x0102);

        assert_eq!(memory.get_u16(0), 0x0102);
    }

    #[test]
    fn test_u32() {
        let mut memory = Memory::new();
        memory.put_u32(0, 0x01020304);

        assert_eq!(memory.get_u32(0), 0x01020304);
    }

    #[test]
    fn test_u64() {
        let mut memory = Memory::new();
        memory.put_u64(0, 0x0102030405060708);

        assert_eq!(memory.get_u64(0), 0x0102030405060708);
    }

    #[test]
    fn test_i8() {
        let mut memory = Memory::new();
        memory.put_i8(0, 0x01);

        assert_eq!(memory.get_i8(0), 0x01);
    }

    #[test]
    fn test_i16() {
        let mut memory = Memory::new();
        memory.put_i16(0, 0x0102);

        assert_eq!(memory.get_i16(0), 0x0102);
    }

    #[test]
    fn test_i32() {
        let mut memory = Memory::new();
        memory.put_i32(0, 0x01020304);

        assert_eq!(memory.get_i32(0), 0x01020304);
    }

    #[test]
    fn test_i64() {
        let mut memory = Memory::new();
        memory.put_i64(0, 0x0102030405060708);

        assert_eq!(memory.get_i64(0), 0x0102030405060708);
    }

    #[test]
    fn test_f32() {
        let mut memory = Memory::new();
        memory.put_f32(0, 0.1);

        assert_eq!(memory.get_f32(0), 0.1);
    }

    #[test]
    fn test_f64() {
        let mut memory = Memory::new();
        memory.put_f64(0, 0.1);

        assert_eq!(memory.get_f64(0), 0.1);
    }
}