Crate wasmtime_runtime

Runtime library support for Wasmtime.

Re-exports

pub use crate::mpk::MpkEnabled;

Modules

libcalls

Runtime library calls.

mpk

Memory Protection Keys (MPK) implementation for use in striped memory allocation.

Structs

AsyncWasmCallState

Opaque state used to persist the state of the CallThreadState activations associated with a fiber stack that’s used as part of an async wasm call.

Backtrace

A WebAssembly stack trace.

CallThreadState

Temporary state stored on the stack which is registered in the tls module below for calls into wasm.

CompiledModuleId

A unique identifier (within an engine or similar) for a compiled module.

CompiledModuleIdAllocator

An allocator for compiled module IDs.

DefaultMemoryCreator

A default memory allocator used by Wasmtime

ExportFunction

A function export value.

ExportGlobal

A global export value.

ExportMemory

A memory export value.

ExportTable

A table export value.

ExternRefHostDataId

ID into the externref host data table.

ExternRefHostDataTable

Side table for each externref’s host data value.

Frame

A stack frame within a Wasm stack trace.

GcHeapAllocationIndex

The index of a table allocation within an InstanceAllocator.

GcRoot

A GC root.

GcRootsIter

An iterator over all the roots in a GcRootsList.

GcRootsList

A list of GC roots.

GcStore

GC-related data that is one-to-one with a wasmtime::Store.

I31

A 31-bit integer for use with i31ref.

Imports

Resolved import pointers.

Instance

A type that roughly corresponds to a WebAssembly instance, but is also used for host-defined objects.

InstanceAllocationRequest

Represents a request for a new runtime instance.

InstanceHandle

A handle holding an Instance of a WebAssembly module.

Memory

Representation of a runtime wasm linear memory.

MemoryAllocationIndex

The index of a memory allocation within an InstanceAllocator.

MemoryImage

One backing image for one memory.

MemoryImageSlot

Slot management of a copy-on-write image which can be reused for the pooling allocator.

Mmap

A simple struct consisting of a page-aligned pointer to page-aligned and initially-zeroed memory and a length.

MmapVec

A type akin to Vec<u8>, but backed by mmap and able to be split.

ModuleMemoryImages

Backing images for memories in a module.

OnDemandInstanceAllocator

Represents the on-demand instance allocator.

PreviousAsyncWasmCallState

Opaque state used to help control TLS state across stack switches for async support.

SendSyncPtr

A helper type in Wasmtime to store a raw pointer to T while automatically inferring the Send and Sync traits for the container based on the properties of T.

StoreBox

A Box<T> lookalike for memory that’s stored in a Store<T>

StorePtr

A pointer to a Store. This Option<*mut dyn Store> is wrapped in a struct so that the function to create a &mut dyn Store is a method on a member of InstanceAllocationRequest, rather than on a &mut InstanceAllocationRequest itself, because several use-sites require a split mut borrow on the InstanceAllocationRequest.

TableAllocationIndex

The index of a table allocation within an InstanceAllocator.

Trap

Stores trace message with backtrace.

TypedGcRef

A GC reference to a heap object of concrete type T.

UnwindRegistration

Represents a registration of function unwind information for System V ABI.

VMArrayCallHostFuncContext

The VM*Context for array-call host functions.

VMContext

The VM “context”, which is pointed to by the vmctx arg in Cranelift. This has information about globals, memories, tables, and other runtime state associated with the current instance.

VMFuncRef

The VM caller-checked “funcref” record, for caller-side signature checking.

VMFunctionBody

A placeholder byte-sized type which is just used to provide some amount of type safety when dealing with pointers to JIT-compiled function bodies. Note that it’s deliberately not Copy, as we shouldn’t be carelessly copying function body bytes around.

VMFunctionImport

An imported function.

VMGcHeader

The common header for all objects allocated in a GC heap.

VMGcRef

A raw, unrooted GC reference.

VMGlobalDefinition

The storage for a WebAssembly global defined within the instance.

VMGlobalImport

The fields compiled code needs to access to utilize a WebAssembly global variable imported from another instance.

VMInvokeArgument

The storage for a WebAssembly invocation argument

VMMemoryDefinition

The fields compiled code needs to access to utilize a WebAssembly linear memory defined within the instance, namely the start address and the size in bytes.

VMMemoryImport

The fields compiled code needs to access to utilize a WebAssembly linear memory imported from another instance.

VMNativeCallFunction

A function pointer that exposes the native calling convention.

VMNativeCallHostFuncContext

The VM*Context for native-call host functions.

VMOpaqueContext

An “opaque” version of VMContext which must be explicitly casted to a target context.

VMRuntimeLimits

Structure used to control interrupting wasm code.

VMSharedTypeIndex

An index into the shared type registry, usable for checking signatures at indirect calls.

VMTableDefinition

The fields compiled code needs to access to utilize a WebAssembly table defined within the instance.

VMTableImport

The fields compiled code needs to access to utilize a WebAssembly table imported from another instance.

VMWasmCallFunction

A function pointer that exposes the Wasm calling convention.

WasmFault

Description about a fault that occurred in WebAssembly.

Yield

A small future that yields once and then returns.

Enums

CoreDumpStack

A WebAssembly Coredump

Export

The value of an export passed from one instance to another.

GcProgress

The result of doing an incremental amount of GC.

SharedMemory

Table

Represents an instance’s table.

TableElement

An element going into or coming out of a table.

TrapReason

Enumeration of different methods of raising a trap.

VMExternRef

WaitResult

Result of Memory::atomic_wait32 and Memory::atomic_wait64

Constants

VERSION

Version number of this crate.

Traits

GarbageCollection

A garbage collection process.

GcHeap

A heap that manages garbage-collected objects.

GcHeapObject

A trait implemented by all objects allocated inside a GC heap.

GcRuntime

Trait for integrating a garbage collector with the runtime.

InstanceAllocator

A thing that can allocate instances.

InstanceAllocatorImpl

Trait that represents the hooks needed to implement an instance allocator.

ModuleInfo

Used by the runtime to query module information.

ModuleInfoLookup

Used by the runtime to lookup information about a module given a program counter value.

ModuleRuntimeInfo

Functionality required by this crate for a particular module. This is chiefly needed for lazy initialization of various bits of instance state.

RuntimeLinearMemory

A linear memory

RuntimeMemoryCreator

A memory allocator

Store

Dynamic runtime functionality needed by this crate throughout the execution of a wasm instance.

Functions

catch_traps^⚠

Catches any wasm traps that happen within the execution of closure, returning them as a Result.

catch_unwind_and_longjmp^⚠

Invokes the closure f and returns the result.

default_gc_runtime

disabled_gc_heap

Get a no-op GC heap for when GC is disabled (either statically at compile time or dynamically due to it being turned off in the wasmtime::Config).

get_stack_pointer

init_traps

This function is required to be called before any WebAssembly is entered. This will configure global state such as signal handlers to prepare the process to receive wasm traps.

page_size

Returns the host OS page size, in bytes.

raise_lib_trap^⚠

Raises a trap from inside library code immediately.

raise_trap^⚠

Raises a trap immediately.

raise_user_trap^⚠

Raises a user-defined trap immediately.

tls_eager_initialize

Eagerly initialize thread-local runtime functionality. This will be performed lazily by the runtime if users do not perform it eagerly.

Type Aliases

SignalHandler

Function which may handle custom signals while processing traps.

V128Abi

x86 vectors are represented with XMM registers which are represented with the __m128i type. This type is considered a vector type for ABI purposes which is implemented by Cranelift.

VMArrayCallFunction

A function pointer that exposes the array calling convention.

Unions

ValRaw

A “raw” and unsafe representation of a WebAssembly value.