wasm/core/decoding/modules/
indices.rs

1use crate::{
2    core::{
3        decoding::reader::WasmDecoder,
4        structure::modules::indices::{
5            DataIdx, ElemIdx, FuncIdx, GlobalIdx, Idx, LocalIdx, MemIdx, TableIdx, TypeIdx,
6        },
7    },
8    DecodingError,
9};
10
11impl TypeIdx {
12    /// Reads a type index from Wasm code without validating it. Using the
13    /// returned type requires some other form of validation to be done.
14    ///
15    /// # Safety
16    ///
17    /// The caller must ensure that there is a valid type index in the [`WasmDecoder`].
18    pub unsafe fn decode_unchecked(wasm: &mut WasmDecoder) -> Self {
19        let index = wasm.decode_var_u32().unwrap();
20        <Self as Idx>::new(index)
21    }
22}
23
24impl FuncIdx {
25    /// Reads a function index from Wasm code without validating it.
26    ///
27    /// # Safety
28    ///
29    /// The caller must ensure that there is a valid function index in the [`WasmDecoder`].
30    pub unsafe fn decode_unchecked(wasm: &mut WasmDecoder) -> Self {
31        let index = wasm.decode_var_u32().unwrap();
32        <Self as Idx>::new(index)
33    }
34}
35
36impl TableIdx {
37    /// Reads a table index from Wasm code without validating it.
38    ///
39    /// # Safety
40    ///
41    /// The caller must ensure that there is a valid table index in the [`WasmDecoder`].
42    pub unsafe fn decode_unchecked(wasm: &mut WasmDecoder) -> Self {
43        let index = wasm.decode_var_u32().unwrap();
44        <Self as Idx>::new(index)
45    }
46}
47
48impl MemIdx {
49    /// Reads a memory index from Wasm code without validating it.
50    ///
51    /// # Safety
52    ///
53    /// The caller must ensure that there is a valid memory index in the [`WasmDecoder`].
54    #[allow(unused)] // reason = "unused until multiple memories proposal is implemented"
55    pub unsafe fn decode_unchecked(wasm: &mut WasmDecoder) -> Self {
56        let index = wasm.decode_var_u32().unwrap();
57        Self::new(index)
58    }
59}
60
61impl GlobalIdx {
62    /// Reads a global index from Wasm code without validating it.
63    ///
64    /// # Safety
65    ///
66    /// The caller must ensure that there is a valid global index in the [`WasmDecoder`].
67    pub unsafe fn decode_unchecked(wasm: &mut WasmDecoder) -> Self {
68        let index = wasm.decode_var_u32().unwrap();
69        <Self as Idx>::new(index)
70    }
71}
72
73impl ElemIdx {
74    /// Reads an element index from Wasm code without validating it.
75    ///
76    /// # Safety
77    ///
78    /// The caller must ensure that there is a valid element index in the [`WasmDecoder`].
79    pub unsafe fn decode_unchecked(wasm: &mut WasmDecoder) -> Self {
80        let index = wasm.decode_var_u32().unwrap();
81        <Self as Idx>::new(index)
82    }
83}
84
85impl DataIdx {
86    /// Reads a data index from Wasm code without validating it.
87    ///
88    /// # Safety
89    ///
90    /// The caller must ensure that there is a valid data index in the [`WasmDecoder`].
91    pub unsafe fn decode_unchecked(wasm: &mut WasmDecoder) -> Self {
92        let index = wasm.decode_var_u32().unwrap();
93        <Self as Idx>::new(index)
94    }
95}
96
97impl LocalIdx {
98    /// Reads a local index from Wasm code without validating it.
99    ///
100    /// # Safety
101    ///
102    /// The caller must ensure that there is a valid local index in the [`WasmDecoder`].
103    pub unsafe fn decode_unchecked(wasm: &mut WasmDecoder) -> Self {
104        let index = wasm.decode_var_u32().unwrap();
105        Self(index)
106    }
107}
108
109/// Reads a label index from Wasm code without validating it.
110pub fn decode_label_idx(wasm: &mut WasmDecoder) -> Result<u32, DecodingError> {
111    wasm.decode_var_u32()
112}
113
114/// Reads a label index from Wasm code without validating it.
115///
116/// # Safety
117///
118/// The caller must ensure that there is a valid label index in the [`WasmDecoder`].
119pub unsafe fn decode_label_idx_unchecked(wasm: &mut WasmDecoder) -> u32 {
120    // TODO use `unwrap_unchecked` instead
121    wasm.decode_var_u32().unwrap()
122}
wasm/core/decoding/modules/indices.rs

wasm/core/decoding/modules/
indices.rs
