wasmtime/
runtime.rs

1// Wasmtime's runtime has lots of fiddly bits where we're doing operations like
2// casting between wasm i32/i64 and host `usize` values. There's also in general
3// just lots of pieces of low-level manipulation of memory and internals of VM
4// runtime state. To help keep all the integer casts correct be a bit more
5// strict than the default settings to help weed out bugs ahead of time.
6//
7// This inevitably leads to wordier code than might otherwise be used because,
8// for example, `u64 as usize` is warned against and will be an error on CI.
9// This happens pretty frequently and needs to be replaced with `val.try_into()`
10// or `usize::try_from(val)` where the error is handled. In some cases the
11// correct thing to do is to `.unwrap()` the error to indicate a fatal mistake,
12// but in some cases the correct thing is to propagate the error.
13//
14// Some niche cases that explicitly want truncation are recommended to have a
15// function along the lines of
16//
17//     #[allow(clippy::cast_possible_truncation)]
18//     fn truncate_i32_to_i8(a: i32) -> i8 { a as i8 }
19//
20// as this explicitly indicates the intent of truncation is desired. Other
21// locations should use fallible conversions.
22//
23// If performance is absolutely critical then it's recommended to use `#[allow]`
24// with a comment indicating why performance is critical as well as a short
25// explanation of why truncation shouldn't be happening at runtime. This
26// situation should be pretty rare though.
27#![warn(clippy::cast_possible_truncation)]
28
29#[macro_use]
30pub(crate) mod func;
31
32pub(crate) mod code;
33pub(crate) mod code_memory;
34#[cfg(feature = "debug")]
35pub(crate) mod debug;
36#[cfg(feature = "gc")]
37pub(crate) mod exception;
38pub(crate) mod externals;
39#[cfg(feature = "async")]
40pub(crate) mod fiber;
41pub(crate) mod gc;
42pub(crate) mod instance;
43pub(crate) mod instantiate;
44pub(crate) mod limits;
45pub(crate) mod linker;
46pub(crate) mod memory;
47pub(crate) mod module;
48#[cfg(feature = "debug-builtins")]
49pub(crate) mod native_debug;
50pub(crate) mod resources;
51pub(crate) mod store;
52pub(crate) mod trampoline;
53pub(crate) mod trap;
54pub(crate) mod type_registry;
55pub(crate) mod types;
56pub(crate) mod v128;
57pub(crate) mod values;
58pub(crate) mod vm;
59
60#[cfg(feature = "component-model")]
61pub mod component;
62
63cfg_if::cfg_if! {
64    if #[cfg(miri)] {
65        // no extensions on miri
66    } else if #[cfg(not(feature = "std"))] {
67        // no extensions on no-std
68    } else if #[cfg(unix)] {
69        pub mod unix;
70    } else if #[cfg(windows)] {
71        pub mod windows;
72    } else {
73        // ... unknown os!
74    }
75}
76
77pub use code_memory::CodeMemory;
78#[cfg(feature = "debug")]
79pub use debug::*;
80#[cfg(feature = "gc")]
81pub use exception::*;
82pub use externals::*;
83pub use func::*;
84pub use gc::*;
85pub use instance::{Instance, InstancePre};
86pub use instantiate::CompiledModule;
87pub use limits::*;
88pub use linker::*;
89pub use memory::*;
90pub use module::{Module, ModuleExport};
91pub use resources::*;
92#[cfg(all(feature = "async", feature = "call-hook"))]
93pub use store::CallHookHandler;
94pub use store::{
95    AsContext, AsContextMut, CallHook, Store, StoreContext, StoreContextMut, UpdateDeadline,
96};
97pub use trap::*;
98pub use types::*;
99pub use v128::V128;
100pub use values::*;
101
102#[cfg(feature = "pooling-allocator")]
103pub use vm::{PoolConcurrencyLimitError, PoolingAllocatorMetrics};
104
105#[cfg(feature = "profiling")]
106mod profiling;
107#[cfg(feature = "profiling")]
108pub use profiling::GuestProfiler;
109
110#[cfg(feature = "async")]
111pub(crate) mod stack;
112#[cfg(feature = "async")]
113pub use stack::*;
114
115#[cfg(feature = "coredump")]
116mod coredump;
117#[cfg(feature = "coredump")]
118pub use coredump::*;
119
120#[cfg(feature = "wave")]
121mod wave;
122
123fn _assertions_runtime() {
124    use crate::_assert_send_and_sync;
125
126    #[cfg(feature = "async")]
127    fn _assert_send<T: Send>(_t: T) {}
128
129    _assert_send_and_sync::<Caller<'_, ()>>();
130    _assert_send_and_sync::<ExternRef>();
131    _assert_send_and_sync::<(Func, TypedFunc<(), ()>, Global, Table, Memory)>();
132    _assert_send_and_sync::<Instance>();
133    _assert_send_and_sync::<InstancePre<()>>();
134    _assert_send_and_sync::<InstancePre<*mut u8>>();
135    _assert_send_and_sync::<Linker<()>>();
136    _assert_send_and_sync::<Linker<*mut u8>>();
137    _assert_send_and_sync::<Module>();
138    _assert_send_and_sync::<Store<()>>();
139    _assert_send_and_sync::<StoreContext<'_, ()>>();
140    _assert_send_and_sync::<StoreContextMut<'_, ()>>();
141
142    #[cfg(feature = "async")]
143    fn _call_async(s: &mut Store<()>, f: Func) {
144        _assert_send(f.call_async(&mut *s, &[], &mut []))
145    }
146    #[cfg(feature = "async")]
147    fn _typed_call_async(s: &mut Store<()>, f: TypedFunc<(), ()>) {
148        _assert_send(f.call_async(&mut *s, ()))
149    }
150    #[cfg(feature = "async")]
151    fn _instantiate_async(s: &mut Store<()>, m: &Module) {
152        _assert_send(Instance::new_async(s, m, &[]))
153    }
154}
wasmtime/runtime.rs

wasmtime/
runtime.rs
