1 use crate::prelude::*; 2 #[cfg(feature = "std")] 3 use crate::runtime::vm::open_file_for_mmap; 4 use crate::runtime::vm::{CompiledModuleId, MmapVec, ModuleMemoryImages, VMWasmCallFunction}; 5 use crate::sync::OnceLock; 6 use crate::{ 7 Engine, 8 code::EngineCode, 9 code_memory::CodeMemory, 10 instantiate::CompiledModule, 11 resources::ResourcesRequired, 12 types::{ExportType, ExternType, ImportType}, 13 }; 14 use alloc::sync::Arc; 15 use core::fmt; 16 use core::ops::Range; 17 use core::ptr::NonNull; 18 #[cfg(feature = "std")] 19 use std::{fs::File, path::Path}; 20 use wasmparser::{Parser, ValidPayload, Validator}; 21 #[cfg(feature = "debug")] 22 use wasmtime_environ::FrameTable; 23 use wasmtime_environ::{ 24 CompiledFunctionsTable, CompiledModuleInfo, EntityIndex, HostPtr, ModuleTypes, ObjectKind, 25 TypeTrace, VMOffsets, VMSharedTypeIndex, WasmChecksum, 26 }; 27 #[cfg(feature = "gc")] 28 use wasmtime_unwinder::ExceptionTable; 29 mod registry; 30 31 pub use registry::*; 32 33 /// A compiled WebAssembly module, ready to be instantiated. 34 /// 35 /// A `Module` is a compiled in-memory representation of an input WebAssembly 36 /// binary. A `Module` is then used to create an [`Instance`](crate::Instance) 37 /// through an instantiation process. You cannot call functions or fetch 38 /// globals, for example, on a `Module` because it's purely a code 39 /// representation. Instead you'll need to create an 40 /// [`Instance`](crate::Instance) to interact with the wasm module. 41 /// 42 /// A `Module` can be created by compiling WebAssembly code through APIs such as 43 /// [`Module::new`]. This would be a JIT-style use case where code is compiled 44 /// just before it's used. Alternatively a `Module` can be compiled in one 45 /// process and [`Module::serialize`] can be used to save it to storage. A later 46 /// call to [`Module::deserialize`] will quickly load the module to execute and 47 /// does not need to compile any code, representing a more AOT-style use case. 48 /// 49 /// Currently a `Module` does not implement any form of tiering or dynamic 50 /// optimization of compiled code. Creation of a `Module` via [`Module::new`] or 51 /// related APIs will perform the entire compilation step synchronously. When 52 /// finished no further compilation will happen at runtime or later during 53 /// execution of WebAssembly instances for example. 54 /// 55 /// Compilation of WebAssembly by default goes through Cranelift and is 56 /// recommended to be done once-per-module. The same WebAssembly binary need not 57 /// be compiled multiple times and can instead used an embedder-cached result of 58 /// the first call. 59 /// 60 /// `Module` is thread-safe and safe to share across threads. 61 /// 62 /// ## Modules and `Clone` 63 /// 64 /// Using `clone` on a `Module` is a cheap operation. It will not create an 65 /// entirely new module, but rather just a new reference to the existing module. 66 /// In other words it's a shallow copy, not a deep copy. 67 /// 68 /// ## Examples 69 /// 70 /// There are a number of ways you can create a `Module`, for example pulling 71 /// the bytes from a number of locations. One example is loading a module from 72 /// the filesystem: 73 /// 74 /// ```no_run 75 /// # use wasmtime::*; 76 /// # fn main() -> Result<()> { 77 /// let engine = Engine::default(); 78 /// let module = Module::from_file(&engine, "path/to/foo.wasm")?; 79 /// # Ok(()) 80 /// # } 81 /// ``` 82 /// 83 /// You can also load the wasm text format if more convenient too: 84 /// 85 /// ```no_run 86 /// # use wasmtime::*; 87 /// # fn main() -> Result<()> { 88 /// let engine = Engine::default(); 89 /// // Now we're using the WebAssembly text extension: `.wat`! 90 /// let module = Module::from_file(&engine, "path/to/foo.wat")?; 91 /// # Ok(()) 92 /// # } 93 /// ``` 94 /// 95 /// And if you've already got the bytes in-memory you can use the 96 /// [`Module::new`] constructor: 97 /// 98 /// ```no_run 99 /// # use wasmtime::*; 100 /// # fn main() -> Result<()> { 101 /// let engine = Engine::default(); 102 /// # let wasm_bytes: Vec<u8> = Vec::new(); 103 /// let module = Module::new(&engine, &wasm_bytes)?; 104 /// 105 /// // It also works with the text format! 106 /// let module = Module::new(&engine, "(module (func))")?; 107 /// # Ok(()) 108 /// # } 109 /// ``` 110 /// 111 /// Serializing and deserializing a module looks like: 112 /// 113 /// ```no_run 114 /// # use wasmtime::*; 115 /// # fn main() -> Result<()> { 116 /// let engine = Engine::default(); 117 /// # let wasm_bytes: Vec<u8> = Vec::new(); 118 /// let module = Module::new(&engine, &wasm_bytes)?; 119 /// let module_bytes = module.serialize()?; 120 /// 121 /// // ... can save `module_bytes` to disk or other storage ... 122 /// 123 /// // recreate the module from the serialized bytes. For the `unsafe` bits 124 /// // see the documentation of `deserialize`. 125 /// let module = unsafe { Module::deserialize(&engine, &module_bytes)? }; 126 /// # Ok(()) 127 /// # } 128 /// ``` 129 /// 130 /// [`Config`]: crate::Config 131 #[derive(Clone)] 132 pub struct Module { 133 inner: Arc<ModuleInner>, 134 } 135 136 struct ModuleInner { 137 engine: Engine, 138 /// The compiled artifacts for this module that will be instantiated and 139 /// executed. 140 module: CompiledModule, 141 142 /// Runtime information such as the underlying mmap, type information, etc. 143 /// 144 /// Note that this `Arc` is used to share information between compiled 145 /// modules within a component. For bare core wasm modules created with 146 /// `Module::new`, for example, this is a uniquely owned `Arc`. 147 code: Arc<EngineCode>, 148 149 /// A set of initialization images for memories, if any. 150 /// 151 /// Note that this is behind a `OnceCell` to lazily create this image. On 152 /// Linux where `memfd_create` may be used to create the backing memory 153 /// image this is a pretty expensive operation, so by deferring it this 154 /// improves memory usage for modules that are created but may not ever be 155 /// instantiated. 156 memory_images: OnceLock<Option<ModuleMemoryImages>>, 157 158 /// Flag indicating whether this module can be serialized or not. 159 #[cfg(any(feature = "cranelift", feature = "winch"))] 160 serializable: bool, 161 162 /// Runtime offset information for `VMContext`. 163 offsets: VMOffsets<HostPtr>, 164 165 /// The checksum of the source binary from which this module was compiled. 166 checksum: WasmChecksum, 167 } 168 169 impl fmt::Debug for Module { 170 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { 171 f.debug_struct("Module") 172 .field("name", &self.name()) 173 .finish_non_exhaustive() 174 } 175 } 176 177 impl fmt::Debug for ModuleInner { 178 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { 179 f.debug_struct("ModuleInner") 180 .field("name", &self.module.module().name.as_ref()) 181 .finish_non_exhaustive() 182 } 183 } 184 185 impl Module { 186 /// Creates a new WebAssembly `Module` from the given in-memory `bytes`. 187 /// 188 /// The `bytes` provided must be in one of the following formats: 189 /// 190 /// * A [binary-encoded][binary] WebAssembly module. This is always supported. 191 /// * A [text-encoded][text] instance of the WebAssembly text format. 192 /// This is only supported when the `wat` feature of this crate is enabled. 193 /// If this is supplied then the text format will be parsed before validation. 194 /// Note that the `wat` feature is enabled by default. 195 /// 196 /// The data for the wasm module must be loaded in-memory if it's present 197 /// elsewhere, for example on disk. This requires that the entire binary is 198 /// loaded into memory all at once, this API does not support streaming 199 /// compilation of a module. 200 /// 201 /// The WebAssembly binary will be decoded and validated. It will also be 202 /// compiled according to the configuration of the provided `engine`. 203 /// 204 /// # Errors 205 /// 206 /// This function may fail and return an error. Errors may include 207 /// situations such as: 208 /// 209 /// * The binary provided could not be decoded because it's not a valid 210 /// WebAssembly binary 211 /// * The WebAssembly binary may not validate (e.g. contains type errors) 212 /// * Implementation-specific limits were exceeded with a valid binary (for 213 /// example too many locals) 214 /// * The wasm binary may use features that are not enabled in the 215 /// configuration of `engine` 216 /// * If the `wat` feature is enabled and the input is text, then it may be 217 /// rejected if it fails to parse. 218 /// 219 /// The error returned should contain full information about why module 220 /// creation failed if one is returned. 221 /// 222 /// [binary]: https://webassembly.github.io/spec/core/binary/index.html 223 /// [text]: https://webassembly.github.io/spec/core/text/index.html 224 /// 225 /// # Examples 226 /// 227 /// The `new` function can be invoked with a in-memory array of bytes: 228 /// 229 /// ```no_run 230 /// # use wasmtime::*; 231 /// # fn main() -> Result<()> { 232 /// # let engine = Engine::default(); 233 /// # let wasm_bytes: Vec<u8> = Vec::new(); 234 /// let module = Module::new(&engine, &wasm_bytes)?; 235 /// # Ok(()) 236 /// # } 237 /// ``` 238 /// 239 /// Or you can also pass in a string to be parsed as the wasm text 240 /// format: 241 /// 242 /// ``` 243 /// # use wasmtime::*; 244 /// # fn main() -> Result<()> { 245 /// # let engine = Engine::default(); 246 /// let module = Module::new(&engine, "(module (func))")?; 247 /// # Ok(()) 248 /// # } 249 /// ``` 250 #[cfg(any(feature = "cranelift", feature = "winch"))] 251 pub fn new(engine: &Engine, bytes: impl AsRef<[u8]>) -> Result<Module> { 252 crate::CodeBuilder::new(engine) 253 .wasm_binary_or_text(bytes.as_ref(), None)? 254 .compile_module() 255 } 256 257 /// Creates a new WebAssembly `Module` from the contents of the given 258 /// `file` on disk. 259 /// 260 /// This is a convenience function that will read the `file` provided and 261 /// pass the bytes to the [`Module::new`] function. For more information 262 /// see [`Module::new`] 263 /// 264 /// # Examples 265 /// 266 /// ```no_run 267 /// # use wasmtime::*; 268 /// # fn main() -> Result<()> { 269 /// let engine = Engine::default(); 270 /// let module = Module::from_file(&engine, "./path/to/foo.wasm")?; 271 /// # Ok(()) 272 /// # } 273 /// ``` 274 /// 275 /// The `.wat` text format is also supported: 276 /// 277 /// ```no_run 278 /// # use wasmtime::*; 279 /// # fn main() -> Result<()> { 280 /// # let engine = Engine::default(); 281 /// let module = Module::from_file(&engine, "./path/to/foo.wat")?; 282 /// # Ok(()) 283 /// # } 284 /// ``` 285 #[cfg(all(feature = "std", any(feature = "cranelift", feature = "winch")))] 286 pub fn from_file(engine: &Engine, file: impl AsRef<Path>) -> Result<Module> { 287 crate::CodeBuilder::new(engine) 288 .wasm_binary_or_text_file(file.as_ref())? 289 .compile_module() 290 } 291 292 /// Creates a new WebAssembly `Module` from the given in-memory `binary` 293 /// data. 294 /// 295 /// This is similar to [`Module::new`] except that it requires that the 296 /// `binary` input is a WebAssembly binary, the text format is not supported 297 /// by this function. It's generally recommended to use [`Module::new`], but 298 /// if it's required to not support the text format this function can be 299 /// used instead. 300 /// 301 /// # Examples 302 /// 303 /// ``` 304 /// # use wasmtime::*; 305 /// # fn main() -> Result<()> { 306 /// # let engine = Engine::default(); 307 /// let wasm = b"\0asm\x01\0\0\0"; 308 /// let module = Module::from_binary(&engine, wasm)?; 309 /// # Ok(()) 310 /// # } 311 /// ``` 312 /// 313 /// Note that the text format is **not** accepted by this function: 314 /// 315 /// ``` 316 /// # use wasmtime::*; 317 /// # fn main() -> Result<()> { 318 /// # let engine = Engine::default(); 319 /// assert!(Module::from_binary(&engine, b"(module)").is_err()); 320 /// # Ok(()) 321 /// # } 322 /// ``` 323 #[cfg(any(feature = "cranelift", feature = "winch"))] 324 pub fn from_binary(engine: &Engine, binary: &[u8]) -> Result<Module> { 325 crate::CodeBuilder::new(engine) 326 .wasm_binary(binary, None)? 327 .compile_module() 328 } 329 330 /// Creates a new WebAssembly `Module` from the contents of the given `file` 331 /// on disk, but with assumptions that the file is from a trusted source. 332 /// The file should be a binary- or text-format WebAssembly module, or a 333 /// precompiled artifact generated by the same version of Wasmtime. 334 /// 335 /// # Unsafety 336 /// 337 /// All of the reasons that [`deserialize`] is `unsafe` apply to this 338 /// function as well. Arbitrary data loaded from a file may trick Wasmtime 339 /// into arbitrary code execution since the contents of the file are not 340 /// validated to be a valid precompiled module. 341 /// 342 /// [`deserialize`]: Module::deserialize 343 /// 344 /// Additionally though this function is also `unsafe` because the file 345 /// referenced must remain unchanged and a valid precompiled module for the 346 /// entire lifetime of the [`Module`] returned. Any changes to the file on 347 /// disk may change future instantiations of the module to be incorrect. 348 /// This is because the file is mapped into memory and lazily loaded pages 349 /// reflect the current state of the file, not necessarily the original 350 /// state of the file. 351 #[cfg(all(feature = "std", any(feature = "cranelift", feature = "winch")))] 352 pub unsafe fn from_trusted_file(engine: &Engine, file: impl AsRef<Path>) -> Result<Module> { 353 let open_file = open_file_for_mmap(file.as_ref())?; 354 let mmap = crate::runtime::vm::MmapVec::from_file(open_file)?; 355 if &mmap[0..4] == b"\x7fELF" { 356 let code = engine.load_code(mmap, ObjectKind::Module)?; 357 return Module::from_parts(engine, code, None); 358 } 359 360 crate::CodeBuilder::new(engine) 361 .wasm_binary_or_text(&mmap[..], Some(file.as_ref()))? 362 .compile_module() 363 } 364 365 /// Deserializes an in-memory compiled module previously created with 366 /// [`Module::serialize`] or [`Engine::precompile_module`]. 367 /// 368 /// This function will deserialize the binary blobs emitted by 369 /// [`Module::serialize`] and [`Engine::precompile_module`] back into an 370 /// in-memory [`Module`] that's ready to be instantiated. 371 /// 372 /// Note that the [`Module::deserialize_file`] method is more optimized than 373 /// this function, so if the serialized module is already present in a file 374 /// it's recommended to use that method instead. 375 /// 376 /// # Unsafety 377 /// 378 /// This function is marked as `unsafe` because if fed invalid input or used 379 /// improperly this could lead to memory safety vulnerabilities. This method 380 /// should not, for example, be exposed to arbitrary user input. 381 /// 382 /// The structure of the binary blob read here is only lightly validated 383 /// internally in `wasmtime`. This is intended to be an efficient 384 /// "rehydration" for a [`Module`] which has very few runtime checks beyond 385 /// deserialization. Arbitrary input could, for example, replace valid 386 /// compiled code with any other valid compiled code, meaning that this can 387 /// trivially be used to execute arbitrary code otherwise. 388 /// 389 /// For these reasons this function is `unsafe`. This function is only 390 /// designed to receive the previous input from [`Module::serialize`] and 391 /// [`Engine::precompile_module`]. If the exact output of those functions 392 /// (unmodified) is passed to this function then calls to this function can 393 /// be considered safe. It is the caller's responsibility to provide the 394 /// guarantee that only previously-serialized bytes are being passed in 395 /// here. 396 /// 397 /// Note that this function is designed to be safe receiving output from 398 /// *any* compiled version of `wasmtime` itself. This means that it is safe 399 /// to feed output from older versions of Wasmtime into this function, in 400 /// addition to newer versions of wasmtime (from the future!). These inputs 401 /// will deterministically and safely produce an `Err`. This function only 402 /// successfully accepts inputs from the same version of `wasmtime`, but the 403 /// safety guarantee only applies to externally-defined blobs of bytes, not 404 /// those defined by any version of wasmtime. (this means that if you cache 405 /// blobs across versions of wasmtime you can be safely guaranteed that 406 /// future versions of wasmtime will reject old cache entries). 407 pub unsafe fn deserialize(engine: &Engine, bytes: impl AsRef<[u8]>) -> Result<Module> { 408 let code = engine.load_code_bytes(bytes.as_ref(), ObjectKind::Module)?; 409 Module::from_parts(engine, code, None) 410 } 411 412 /// In-place deserialization of an in-memory compiled module previously 413 /// created with [`Module::serialize`] or [`Engine::precompile_module`]. 414 /// 415 /// See [`Self::deserialize`] for additional information; this method 416 /// works identically except that it will not create a copy of the provided 417 /// memory but will use it directly. 418 /// 419 /// # Unsafety 420 /// 421 /// All of the safety notes from [`Self::deserialize`] apply here as well 422 /// with the additional constraint that the code memory provide by `memory` 423 /// lives for as long as the module and is nevery externally modified for 424 /// the lifetime of the deserialized module. 425 pub unsafe fn deserialize_raw(engine: &Engine, memory: NonNull<[u8]>) -> Result<Module> { 426 // SAFETY: the contract required by `load_code_raw` is the same as this 427 // function. 428 let code = unsafe { engine.load_code_raw(memory, ObjectKind::Module)? }; 429 Module::from_parts(engine, code, None) 430 } 431 432 /// Same as [`deserialize`], except that the contents of `path` are read to 433 /// deserialize into a [`Module`]. 434 /// 435 /// This method is provided because it can be faster than [`deserialize`] 436 /// since the data doesn't need to be copied around, but rather the module 437 /// can be used directly from an mmap'd view of the file provided. 438 /// 439 /// [`deserialize`]: Module::deserialize 440 /// 441 /// # Unsafety 442 /// 443 /// All of the reasons that [`deserialize`] is `unsafe` applies to this 444 /// function as well. Arbitrary data loaded from a file may trick Wasmtime 445 /// into arbitrary code execution since the contents of the file are not 446 /// validated to be a valid precompiled module. 447 /// 448 /// Additionally though this function is also `unsafe` because the file 449 /// referenced must remain unchanged and a valid precompiled module for the 450 /// entire lifetime of the [`Module`] returned. Any changes to the file on 451 /// disk may change future instantiations of the module to be incorrect. 452 /// This is because the file is mapped into memory and lazily loaded pages 453 /// reflect the current state of the file, not necessarily the original 454 /// state of the file. 455 #[cfg(feature = "std")] 456 pub unsafe fn deserialize_file(engine: &Engine, path: impl AsRef<Path>) -> Result<Module> { 457 let file = open_file_for_mmap(path.as_ref())?; 458 // SAFETY: the contract of `deserialize_open_file` is the samea s this 459 // function. 460 unsafe { 461 Self::deserialize_open_file(engine, file) 462 .with_context(|| format!("failed deserialization for: {}", path.as_ref().display())) 463 } 464 } 465 466 /// Same as [`deserialize_file`], except that it takes an open `File` 467 /// instead of a path. 468 /// 469 /// This method is provided because it can be used instead of 470 /// [`deserialize_file`] in situations where `wasmtime` is running with 471 /// limited file system permissions. In that case a process 472 /// with file system access can pass already opened files to `wasmtime`. 473 /// 474 /// [`deserialize_file`]: Module::deserialize_file 475 /// 476 /// Note that the corresponding will be mapped as private writeable 477 /// (copy-on-write) and executable. For `windows` this means the file needs 478 /// to be opened with at least `FILE_GENERIC_READ | FILE_GENERIC_EXECUTE` 479 /// [`access_mode`]. 480 /// 481 /// [`access_mode`]: https://doc.rust-lang.org/std/os/windows/fs/trait.OpenOptionsExt.html#tymethod.access_mode 482 /// 483 /// # Unsafety 484 /// 485 /// All of the reasons that [`deserialize_file`] is `unsafe` applies to this 486 /// function as well. 487 #[cfg(feature = "std")] 488 pub unsafe fn deserialize_open_file(engine: &Engine, file: File) -> Result<Module> { 489 let code = engine.load_code_file(file, ObjectKind::Module)?; 490 Module::from_parts(engine, code, None) 491 } 492 493 /// Entrypoint for creating a `Module` for all above functions, both 494 /// of the AOT and jit-compiled categories. 495 /// 496 /// In all cases the compilation artifact, `code_memory`, is provided here. 497 /// The `info_and_types` argument is `None` when a module is being 498 /// deserialized from a precompiled artifact or it's `Some` if it was just 499 /// compiled and the values are already available. 500 pub(crate) fn from_parts( 501 engine: &Engine, 502 code_memory: Arc<CodeMemory>, 503 info_and_types: Option<(CompiledModuleInfo, CompiledFunctionsTable, ModuleTypes)>, 504 ) -> Result<Self> { 505 // Acquire this module's metadata and type information, deserializing 506 // it from the provided artifact if it wasn't otherwise provided 507 // already. 508 let (mut info, index, mut types) = match info_and_types { 509 Some((info, index, types)) => (info, index, types), 510 None => postcard::from_bytes(code_memory.wasmtime_info())?, 511 }; 512 513 // Register function type signatures into the engine for the lifetime 514 // of the `Module` that will be returned. This notably also builds up 515 // maps for trampolines to be used for this module when inserted into 516 // stores. 517 // 518 // Note that the unsafety here should be ok since the `trampolines` 519 // field should only point to valid trampoline function pointers 520 // within the text section. 521 let signatures = engine 522 .register_and_canonicalize_types(&mut types, core::iter::once(&mut info.module))?; 523 524 // Package up all our data into an `EngineCode` and delegate to the final 525 // step of module compilation. 526 let code = Arc::new(EngineCode::new(code_memory, signatures, types.into())); 527 let index = Arc::new(index); 528 Module::from_parts_raw(engine, code, info, index, true) 529 } 530 531 pub(crate) fn from_parts_raw( 532 engine: &Engine, 533 code: Arc<EngineCode>, 534 info: CompiledModuleInfo, 535 index: Arc<CompiledFunctionsTable>, 536 serializable: bool, 537 ) -> Result<Self> { 538 let checksum = info.checksum; 539 let module = CompiledModule::from_artifacts(code.clone(), info, index, engine.profiler())?; 540 541 // Validate the module can be used with the current instance allocator. 542 let offsets = VMOffsets::new(HostPtr, module.module()); 543 engine 544 .allocator() 545 .validate_module(module.module(), &offsets)?; 546 547 let _ = serializable; 548 549 Ok(Self { 550 inner: Arc::new(ModuleInner { 551 engine: engine.clone(), 552 code, 553 memory_images: OnceLock::new(), 554 module, 555 #[cfg(any(feature = "cranelift", feature = "winch"))] 556 serializable, 557 offsets, 558 checksum, 559 }), 560 }) 561 } 562 563 /// Validates `binary` input data as a WebAssembly binary given the 564 /// configuration in `engine`. 565 /// 566 /// This function will perform a speedy validation of the `binary` input 567 /// WebAssembly module (which is in [binary form][binary], the text format 568 /// is not accepted by this function) and return either `Ok` or `Err` 569 /// depending on the results of validation. The `engine` argument indicates 570 /// configuration for WebAssembly features, for example, which are used to 571 /// indicate what should be valid and what shouldn't be. 572 /// 573 /// Validation automatically happens as part of [`Module::new`]. 574 /// 575 /// # Errors 576 /// 577 /// If validation fails for any reason (type check error, usage of a feature 578 /// that wasn't enabled, etc) then an error with a description of the 579 /// validation issue will be returned. 580 /// 581 /// [binary]: https://webassembly.github.io/spec/core/binary/index.html 582 pub fn validate(engine: &Engine, binary: &[u8]) -> Result<()> { 583 let mut validator = Validator::new_with_features(engine.features()); 584 585 let mut functions = Vec::new(); 586 for payload in Parser::new(0).parse_all(binary) { 587 let payload = payload?; 588 if let ValidPayload::Func(a, b) = validator.payload(&payload)? { 589 functions.push((a, b)); 590 } 591 if let wasmparser::Payload::Version { encoding, .. } = &payload { 592 if let wasmparser::Encoding::Component = encoding { 593 bail!("component passed to module validation"); 594 } 595 } 596 } 597 598 engine.run_maybe_parallel(functions, |(validator, body)| { 599 // FIXME: it would be best here to use a rayon-specific parallel 600 // iterator that maintains state-per-thread to share the function 601 // validator allocations (`Default::default` here) across multiple 602 // functions. 603 validator.into_validator(Default::default()).validate(&body) 604 })?; 605 Ok(()) 606 } 607 608 /// Serializes this module to a vector of bytes. 609 /// 610 /// This function is similar to the [`Engine::precompile_module`] method 611 /// where it produces an artifact of Wasmtime which is suitable to later 612 /// pass into [`Module::deserialize`]. If a module is never instantiated 613 /// then it's recommended to use [`Engine::precompile_module`] instead of 614 /// this method, but if a module is both instantiated and serialized then 615 /// this method can be useful to get the serialized version without 616 /// compiling twice. 617 #[cfg(any(feature = "cranelift", feature = "winch"))] 618 pub fn serialize(&self) -> Result<Vec<u8>> { 619 // The current representation of compiled modules within a compiled 620 // component means that it cannot be serialized. The mmap returned here 621 // is the mmap for the entire component and while it contains all 622 // necessary data to deserialize this particular module it's all 623 // embedded within component-specific information. 624 // 625 // It's not the hardest thing in the world to support this but it's 626 // expected that there's not much of a use case at this time. In theory 627 // all that needs to be done is to edit the `.wasmtime.info` section 628 // to contains this module's metadata instead of the metadata for the 629 // whole component. The metadata itself is fairly trivially 630 // recreateable here it's more that there's no easy one-off API for 631 // editing the sections of an ELF object to use here. 632 // 633 // Overall for now this simply always returns an error in this 634 // situation. If you're reading this and feel that the situation should 635 // be different please feel free to open an issue. 636 if !self.inner.serializable { 637 bail!("cannot serialize a module exported from a component"); 638 } 639 Ok(self.engine_code().image().to_vec()) 640 } 641 642 pub(crate) fn compiled_module(&self) -> &CompiledModule { 643 &self.inner.module 644 } 645 646 pub(crate) fn engine_code(&self) -> &Arc<EngineCode> { 647 &self.inner.code 648 } 649 650 pub(crate) fn env_module(&self) -> &Arc<wasmtime_environ::Module> { 651 self.compiled_module().module() 652 } 653 654 pub(crate) fn types(&self) -> &ModuleTypes { 655 self.inner.code.module_types() 656 } 657 658 #[cfg(any(feature = "component-model", feature = "gc-drc"))] 659 pub(crate) fn signatures(&self) -> &crate::type_registry::TypeCollection { 660 self.inner.code.signatures() 661 } 662 663 /// Returns identifier/name that this [`Module`] has. This name 664 /// is used in traps/backtrace details. 665 /// 666 /// Note that most LLVM/clang/Rust-produced modules do not have a name 667 /// associated with them, but other wasm tooling can be used to inject or 668 /// add a name. 669 /// 670 /// # Examples 671 /// 672 /// ``` 673 /// # use wasmtime::*; 674 /// # fn main() -> Result<()> { 675 /// # let engine = Engine::default(); 676 /// let module = Module::new(&engine, "(module $foo)")?; 677 /// assert_eq!(module.name(), Some("foo")); 678 /// 679 /// let module = Module::new(&engine, "(module)")?; 680 /// assert_eq!(module.name(), None); 681 /// 682 /// # Ok(()) 683 /// # } 684 /// ``` 685 pub fn name(&self) -> Option<&str> { 686 let module = self.compiled_module().module(); 687 let name = module.name?; 688 Some(&module.strings[name]) 689 } 690 691 /// Returns the list of imports that this [`Module`] has and must be 692 /// satisfied. 693 /// 694 /// This function returns the list of imports that the wasm module has, but 695 /// only the types of each import. The type of each import is used to 696 /// typecheck the [`Instance::new`](crate::Instance::new) method's `imports` 697 /// argument. The arguments to that function must match up 1-to-1 with the 698 /// entries in the array returned here. 699 /// 700 /// The imports returned reflect the order of the imports in the wasm module 701 /// itself, and note that no form of deduplication happens. 702 /// 703 /// # Examples 704 /// 705 /// Modules with no imports return an empty list here: 706 /// 707 /// ``` 708 /// # use wasmtime::*; 709 /// # fn main() -> Result<()> { 710 /// # let engine = Engine::default(); 711 /// let module = Module::new(&engine, "(module)")?; 712 /// assert_eq!(module.imports().len(), 0); 713 /// # Ok(()) 714 /// # } 715 /// ``` 716 /// 717 /// and modules with imports will have a non-empty list: 718 /// 719 /// ``` 720 /// # use wasmtime::*; 721 /// # fn main() -> Result<()> { 722 /// # let engine = Engine::default(); 723 /// let wat = r#" 724 /// (module 725 /// (import "host" "foo" (func)) 726 /// ) 727 /// "#; 728 /// let module = Module::new(&engine, wat)?; 729 /// assert_eq!(module.imports().len(), 1); 730 /// let import = module.imports().next().unwrap(); 731 /// assert_eq!(import.module(), "host"); 732 /// assert_eq!(import.name(), "foo"); 733 /// match import.ty() { 734 /// ExternType::Func(_) => { /* ... */ } 735 /// _ => panic!("unexpected import type!"), 736 /// } 737 /// # Ok(()) 738 /// # } 739 /// ``` 740 pub fn imports<'module>( 741 &'module self, 742 ) -> impl ExactSizeIterator<Item = ImportType<'module>> + 'module { 743 let module = self.compiled_module().module(); 744 let types = self.types(); 745 let engine = self.engine(); 746 module 747 .imports() 748 .map(move |(imp_mod, imp_field, ty)| { 749 debug_assert!(ty.is_canonicalized_for_runtime_usage()); 750 ImportType::new(imp_mod, imp_field, ty, types, engine) 751 }) 752 .collect::<Vec<_>>() 753 .into_iter() 754 } 755 756 /// Returns the list of exports that this [`Module`] has and will be 757 /// available after instantiation. 758 /// 759 /// This function will return the type of each item that will be returned 760 /// from [`Instance::exports`](crate::Instance::exports). Each entry in this 761 /// list corresponds 1-to-1 with that list, and the entries here will 762 /// indicate the name of the export along with the type of the export. 763 /// 764 /// # Examples 765 /// 766 /// Modules might not have any exports: 767 /// 768 /// ``` 769 /// # use wasmtime::*; 770 /// # fn main() -> Result<()> { 771 /// # let engine = Engine::default(); 772 /// let module = Module::new(&engine, "(module)")?; 773 /// assert!(module.exports().next().is_none()); 774 /// # Ok(()) 775 /// # } 776 /// ``` 777 /// 778 /// When the exports are not empty, you can inspect each export: 779 /// 780 /// ``` 781 /// # use wasmtime::*; 782 /// # fn main() -> Result<()> { 783 /// # let engine = Engine::default(); 784 /// let wat = r#" 785 /// (module 786 /// (func (export "foo")) 787 /// (memory (export "memory") 1) 788 /// ) 789 /// "#; 790 /// let module = Module::new(&engine, wat)?; 791 /// assert_eq!(module.exports().len(), 2); 792 /// 793 /// let mut exports = module.exports(); 794 /// let foo = exports.next().unwrap(); 795 /// assert_eq!(foo.name(), "foo"); 796 /// match foo.ty() { 797 /// ExternType::Func(_) => { /* ... */ } 798 /// _ => panic!("unexpected export type!"), 799 /// } 800 /// 801 /// let memory = exports.next().unwrap(); 802 /// assert_eq!(memory.name(), "memory"); 803 /// match memory.ty() { 804 /// ExternType::Memory(_) => { /* ... */ } 805 /// _ => panic!("unexpected export type!"), 806 /// } 807 /// # Ok(()) 808 /// # } 809 /// ``` 810 pub fn exports<'module>( 811 &'module self, 812 ) -> impl ExactSizeIterator<Item = ExportType<'module>> + 'module { 813 let module = self.compiled_module().module(); 814 let types = self.types(); 815 let engine = self.engine(); 816 module.exports.iter().map(move |(name, entity_index)| { 817 ExportType::new( 818 &module.strings[name], 819 module.type_of(*entity_index), 820 types, 821 engine, 822 ) 823 }) 824 } 825 826 /// Looks up an export in this [`Module`] by name. 827 /// 828 /// This function will return the type of an export with the given name. 829 /// 830 /// # Examples 831 /// 832 /// There may be no export with that name: 833 /// 834 /// ``` 835 /// # use wasmtime::*; 836 /// # fn main() -> Result<()> { 837 /// # let engine = Engine::default(); 838 /// let module = Module::new(&engine, "(module)")?; 839 /// assert!(module.get_export("foo").is_none()); 840 /// # Ok(()) 841 /// # } 842 /// ``` 843 /// 844 /// When there is an export with that name, it is returned: 845 /// 846 /// ``` 847 /// # use wasmtime::*; 848 /// # fn main() -> Result<()> { 849 /// # let engine = Engine::default(); 850 /// let wat = r#" 851 /// (module 852 /// (func (export "foo")) 853 /// (memory (export "memory") 1) 854 /// ) 855 /// "#; 856 /// let module = Module::new(&engine, wat)?; 857 /// let foo = module.get_export("foo"); 858 /// assert!(foo.is_some()); 859 /// 860 /// let foo = foo.unwrap(); 861 /// match foo { 862 /// ExternType::Func(_) => { /* ... */ } 863 /// _ => panic!("unexpected export type!"), 864 /// } 865 /// 866 /// # Ok(()) 867 /// # } 868 /// ``` 869 pub fn get_export(&self, name: &str) -> Option<ExternType> { 870 let module = self.compiled_module().module(); 871 let name = module.strings.get_atom(name)?; 872 let entity_index = module.exports.get(&name)?; 873 Some(ExternType::from_wasmtime( 874 self.engine(), 875 self.types(), 876 &module.type_of(*entity_index), 877 )) 878 } 879 880 /// Looks up an export in this [`Module`] by name to get its index. 881 /// 882 /// This function will return the index of an export with the given name. This can be useful 883 /// to avoid the cost of looking up the export by name multiple times. Instead the 884 /// [`ModuleExport`] can be stored and used to look up the export on the 885 /// [`Instance`](crate::Instance) later. 886 pub fn get_export_index(&self, name: &str) -> Option<ModuleExport> { 887 let compiled_module = self.compiled_module(); 888 let module = compiled_module.module(); 889 let name = module.strings.get_atom(name)?; 890 let entity = *module.exports.get(&name)?; 891 Some(ModuleExport { 892 module: self.id(), 893 entity, 894 }) 895 } 896 897 /// Returns the [`Engine`] that this [`Module`] was compiled by. 898 pub fn engine(&self) -> &Engine { 899 &self.inner.engine 900 } 901 902 #[allow( 903 unused, 904 reason = "used only for verification with wasmtime `rr` feature \ 905 and requires a lot of unnecessary gating across crates" 906 )] 907 pub(crate) fn checksum(&self) -> &WasmChecksum { 908 &self.inner.checksum 909 } 910 911 /// Returns a summary of the resources required to instantiate this 912 /// [`Module`]. 913 /// 914 /// Potential uses of the returned information: 915 /// 916 /// * Determining whether your pooling allocator configuration supports 917 /// instantiating this module. 918 /// 919 /// * Deciding how many of which `Module` you want to instantiate within a 920 /// fixed amount of resources, e.g. determining whether to create 5 921 /// instances of module X or 10 instances of module Y. 922 /// 923 /// # Example 924 /// 925 /// ``` 926 /// # fn main() -> wasmtime::Result<()> { 927 /// use wasmtime::{Config, Engine, Module}; 928 /// 929 /// let mut config = Config::new(); 930 /// config.wasm_multi_memory(true); 931 /// let engine = Engine::new(&config)?; 932 /// 933 /// let module = Module::new(&engine, r#" 934 /// (module 935 /// ;; Import a memory. Doesn't count towards required resources. 936 /// (import "a" "b" (memory 10)) 937 /// ;; Define two local memories. These count towards the required 938 /// ;; resources. 939 /// (memory 1) 940 /// (memory 6) 941 /// ) 942 /// "#)?; 943 /// 944 /// let resources = module.resources_required(); 945 /// 946 /// // Instantiating the module will require allocating two memories, and 947 /// // the maximum initial memory size is six Wasm pages. 948 /// assert_eq!(resources.num_memories, 2); 949 /// assert_eq!(resources.max_initial_memory_size, Some(6)); 950 /// 951 /// // The module doesn't need any tables. 952 /// assert_eq!(resources.num_tables, 0); 953 /// assert_eq!(resources.max_initial_table_size, None); 954 /// # Ok(()) } 955 /// ``` 956 pub fn resources_required(&self) -> ResourcesRequired { 957 let em = self.env_module(); 958 let num_memories = u32::try_from(em.num_defined_memories()).unwrap(); 959 let max_initial_memory_size = em 960 .memories 961 .values() 962 .skip(em.num_imported_memories) 963 .map(|memory| memory.limits.min) 964 .max(); 965 let num_tables = u32::try_from(em.num_defined_tables()).unwrap(); 966 let max_initial_table_size = em 967 .tables 968 .values() 969 .skip(em.num_imported_tables) 970 .map(|table| table.limits.min) 971 .max(); 972 ResourcesRequired { 973 num_memories, 974 max_initial_memory_size, 975 num_tables, 976 max_initial_table_size, 977 } 978 } 979 980 /// Returns the range of bytes in memory where this module's compilation 981 /// image resides. 982 /// 983 /// The compilation image for a module contains executable code, data, debug 984 /// information, etc. This is roughly the same as the `Module::serialize` 985 /// but not the exact same. 986 /// 987 /// The range of memory reported here is exposed to allow low-level 988 /// manipulation of the memory in platform-specific manners such as using 989 /// `mlock` to force the contents to be paged in immediately or keep them 990 /// paged in after they're loaded. 991 /// 992 /// It is not safe to modify the memory in this range, nor is it safe to 993 /// modify the protections of memory in this range. 994 /// 995 /// Note that depending on the engine configuration, this image 996 /// range may not actually be the code that is directly executed. 997 pub fn image_range(&self) -> Range<*const u8> { 998 self.engine_code().image().as_ptr_range() 999 } 1000 1001 /// Force initialization of copy-on-write images to happen here-and-now 1002 /// instead of when they're requested during first instantiation. 1003 /// 1004 /// When [copy-on-write memory 1005 /// initialization](crate::Config::memory_init_cow) is enabled then Wasmtime 1006 /// will lazily create the initialization image for a module. This method 1007 /// can be used to explicitly dictate when this initialization happens. 1008 /// 1009 /// Note that this largely only matters on Linux when memfd is used. 1010 /// Otherwise the copy-on-write image typically comes from disk and in that 1011 /// situation the creation of the image is trivial as the image is always 1012 /// sourced from disk. On Linux, though, when memfd is used a memfd is 1013 /// created and the initialization image is written to it. 1014 /// 1015 /// Also note that this method is not required to be called, it's available 1016 /// as a performance optimization if required but is otherwise handled 1017 /// automatically. 1018 pub fn initialize_copy_on_write_image(&self) -> Result<()> { 1019 self.memory_images()?; 1020 Ok(()) 1021 } 1022 1023 /// Get the map from `.text` section offsets to Wasm binary offsets for this 1024 /// module. 1025 /// 1026 /// Each entry is a (`.text` section offset, Wasm binary offset) pair. 1027 /// 1028 /// Entries are yielded in order of `.text` section offset. 1029 /// 1030 /// Some entries are missing a Wasm binary offset. This is for code that is 1031 /// not associated with any single location in the Wasm binary, or for when 1032 /// source information was optimized away. 1033 /// 1034 /// Not every module has an address map, since address map generation can be 1035 /// turned off on `Config`. 1036 /// 1037 /// There is not an entry for every `.text` section offset. Every offset 1038 /// after an entry's offset, but before the next entry's offset, is 1039 /// considered to map to the same Wasm binary offset as the original 1040 /// entry. For example, the address map will not contain the following 1041 /// sequence of entries: 1042 /// 1043 /// ```ignore 1044 /// [ 1045 /// // ... 1046 /// (10, Some(42)), 1047 /// (11, Some(42)), 1048 /// (12, Some(42)), 1049 /// (13, Some(43)), 1050 /// // ... 1051 /// ] 1052 /// ``` 1053 /// 1054 /// Instead, it will drop the entries for offsets `11` and `12` since they 1055 /// are the same as the entry for offset `10`: 1056 /// 1057 /// ```ignore 1058 /// [ 1059 /// // ... 1060 /// (10, Some(42)), 1061 /// (13, Some(43)), 1062 /// // ... 1063 /// ] 1064 /// ``` 1065 pub fn address_map<'a>(&'a self) -> Option<impl Iterator<Item = (usize, Option<u32>)> + 'a> { 1066 Some( 1067 wasmtime_environ::iterate_address_map(self.engine_code().address_map_data())? 1068 .map(|(offset, file_pos)| (offset as usize, file_pos.file_offset())), 1069 ) 1070 } 1071 1072 /// Get this module's code object's `.text` section, containing its compiled 1073 /// executable code. 1074 pub fn text(&self) -> &[u8] { 1075 self.engine_code().text() 1076 } 1077 1078 /// Get information about functions in this module's `.text` section: their 1079 /// index, name, and offset+length. 1080 /// 1081 /// Results are yielded in a ModuleFunction struct. 1082 pub fn functions<'a>(&'a self) -> impl ExactSizeIterator<Item = ModuleFunction> + 'a { 1083 let module = self.compiled_module(); 1084 self.env_module().defined_func_indices().map(|idx| { 1085 let loc = module.func_loc(idx); 1086 let idx = module.module().func_index(idx); 1087 ModuleFunction { 1088 index: idx, 1089 name: module.func_name(idx).map(|n| n.to_string()), 1090 offset: loc.start as usize, 1091 len: loc.length as usize, 1092 } 1093 }) 1094 } 1095 1096 pub(crate) fn id(&self) -> CompiledModuleId { 1097 self.inner.module.unique_id() 1098 } 1099 1100 pub(crate) fn offsets(&self) -> &VMOffsets<HostPtr> { 1101 &self.inner.offsets 1102 } 1103 1104 /// Return the address, in memory, of the trampoline that allows Wasm to 1105 /// call a array function of the given signature. 1106 /// 1107 /// Note that unlike all other code-pointer-returning functions, 1108 /// this *can* be present on `Module` (without a `StoreCode`) 1109 /// because we can execute the `EngineCode` for trampolines that 1110 /// leave the store to call the host. 1111 pub(crate) fn wasm_to_array_trampoline( 1112 &self, 1113 signature: VMSharedTypeIndex, 1114 ) -> Option<NonNull<VMWasmCallFunction>> { 1115 log::trace!("Looking up trampoline for {signature:?}"); 1116 let trampoline_shared_ty = self.inner.engine.signatures().trampoline_type(signature); 1117 let trampoline_module_ty = self 1118 .inner 1119 .code 1120 .signatures() 1121 .trampoline_type(trampoline_shared_ty)?; 1122 debug_assert!( 1123 self.inner 1124 .engine 1125 .signatures() 1126 .borrow( 1127 self.inner 1128 .code 1129 .signatures() 1130 .shared_type(trampoline_module_ty) 1131 .unwrap() 1132 ) 1133 .unwrap() 1134 .unwrap_func() 1135 .is_trampoline_type() 1136 ); 1137 1138 let ptr = self 1139 .compiled_module() 1140 .wasm_to_array_trampoline(trampoline_module_ty) 1141 .expect("always have a trampoline for the trampoline type") 1142 .as_ptr() 1143 .cast::<VMWasmCallFunction>() 1144 .cast_mut(); 1145 Some(NonNull::new(ptr).unwrap()) 1146 } 1147 1148 pub(crate) fn memory_images(&self) -> Result<Option<&ModuleMemoryImages>> { 1149 let images = self 1150 .inner 1151 .memory_images 1152 .get_or_try_init(|| memory_images(&self.inner))? 1153 .as_ref(); 1154 Ok(images) 1155 } 1156 1157 /// Obtain an exception-table parser on this module's exception metadata. 1158 #[cfg(feature = "gc")] 1159 pub(crate) fn exception_table<'a>(&'a self) -> ExceptionTable<'a> { 1160 ExceptionTable::parse(self.inner.code.exception_tables()) 1161 .expect("Exception tables were validated on module load") 1162 } 1163 1164 /// Obtain a frame-table parser on this module's frame state slot 1165 /// (debug instrumentation) metadata. 1166 #[cfg(feature = "debug")] 1167 pub(crate) fn frame_table<'a>(&'a self) -> Option<FrameTable<'a>> { 1168 let data = self.inner.code.frame_tables(); 1169 if data.is_empty() { 1170 None 1171 } else { 1172 let orig_text = self.inner.code.text(); 1173 Some( 1174 FrameTable::parse(data, orig_text) 1175 .expect("Frame tables were validated on module load"), 1176 ) 1177 } 1178 } 1179 1180 /// Is this `Module` the same as another? 1181 /// 1182 /// Ordinarily, module identity does not matter: a Wasmtime user 1183 /// will create or obtain a module from some source and 1184 /// instantiate it, and any two `Module` objects created from the 1185 /// same source module are interchangeable. However, introspecting 1186 /// module identity may be useful when examining Wasm VM state, 1187 /// e.g. via debug APIs. It is guaranteed that `Module::same` 1188 /// returns true for `Module` objects that reference the same 1189 /// underlying module (e.g., one created via a `clone` of the 1190 /// other). 1191 #[inline] 1192 pub fn same(a: &Module, b: &Module) -> bool { 1193 Arc::ptr_eq(&a.inner, &b.inner) 1194 } 1195 } 1196 1197 /// Describes a function for a given module. 1198 pub struct ModuleFunction { 1199 pub index: wasmtime_environ::FuncIndex, 1200 pub name: Option<String>, 1201 pub offset: usize, 1202 pub len: usize, 1203 } 1204 1205 impl Drop for ModuleInner { 1206 fn drop(&mut self) { 1207 // When a `Module` is being dropped that means that it's no longer 1208 // present in any `Store` and it's additionally not longer held by any 1209 // embedder. Take this opportunity to purge any lingering instantiations 1210 // within a pooling instance allocator, if applicable. 1211 self.engine 1212 .allocator() 1213 .purge_module(self.module.unique_id()); 1214 } 1215 } 1216 1217 /// Describes the location of an export in a module. 1218 #[derive(Copy, Clone)] 1219 pub struct ModuleExport { 1220 /// The module that this export is defined in. 1221 pub(crate) module: CompiledModuleId, 1222 /// A raw index into the wasm module. 1223 pub(crate) entity: EntityIndex, 1224 } 1225 1226 fn _assert_send_sync() { 1227 fn _assert<T: Send + Sync>() {} 1228 _assert::<Module>(); 1229 } 1230 1231 /// Helper method to construct a `ModuleMemoryImages` for an associated 1232 /// `CompiledModule`. 1233 fn memory_images(inner: &Arc<ModuleInner>) -> Result<Option<ModuleMemoryImages>> { 1234 // If initialization via copy-on-write is explicitly disabled in 1235 // configuration then this path is skipped entirely. 1236 if !inner.engine.tunables().memory_init_cow { 1237 return Ok(None); 1238 } 1239 1240 // ... otherwise logic is delegated to the `ModuleMemoryImages::new` 1241 // constructor. 1242 ModuleMemoryImages::new( 1243 &inner.engine, 1244 inner.module.module(), 1245 inner.code.module_memory_image_source(), 1246 ) 1247 } 1248 1249 impl crate::vm::ModuleMemoryImageSource for CodeMemory { 1250 fn wasm_data(&self) -> &[u8] { 1251 <Self>::wasm_data(self) 1252 } 1253 1254 fn mmap(&self) -> Option<&MmapVec> { 1255 Some(<Self>::mmap(self)) 1256 } 1257 } 1258 1259 #[cfg(test)] 1260 mod tests { 1261 use crate::{CodeBuilder, Engine, Module}; 1262 use wasmtime_environ::MemoryInitialization; 1263 1264 #[test] 1265 fn cow_on_by_default() { 1266 let engine = Engine::default(); 1267 let module = Module::new( 1268 &engine, 1269 r#" 1270 (module 1271 (memory 1) 1272 (data (i32.const 100) "abcd") 1273 ) 1274 "#, 1275 ) 1276 .unwrap(); 1277 1278 let init = &module.env_module().memory_initialization; 1279 assert!(matches!(init, MemoryInitialization::Static { .. })); 1280 } 1281 1282 #[test] 1283 #[cfg_attr(miri, ignore)] 1284 fn image_range_is_whole_image() { 1285 let wat = r#" 1286 (module 1287 (memory 1) 1288 (data (i32.const 0) "1234") 1289 (func (export "f") (param i32) (result i32) 1290 local.get 0)) 1291 "#; 1292 let engine = Engine::default(); 1293 let mut builder = CodeBuilder::new(&engine); 1294 builder.wasm_binary_or_text(wat.as_bytes(), None).unwrap(); 1295 let bytes = builder.compile_module_serialized().unwrap(); 1296 1297 let module = unsafe { Module::deserialize(&engine, &bytes).unwrap() }; 1298 let image_range = module.image_range(); 1299 let len = image_range.end.addr() - image_range.start.addr(); 1300 // Length may be strictly greater if it becomes page-aligned. 1301 assert!(len >= bytes.len()); 1302 } 1303 } 1304