Struct wasmtime_environ::ModuleEnvironment

pub struct ModuleEnvironment<'data> { /* fields omitted */ }

Object containing the standalone environment information.

Implementations

impl<'data> ModuleEnvironment<'data>

pub fn new(
    target_config: TargetFrontendConfig,
    tunables: &Tunables,
    features: &WasmFeatures
) -> Self

Allocates the environment data structures.

pub fn translate(
    self,
    data: &'data [u8]
) -> WasmResult<(usize, Vec<ModuleTranslation<'data>>, TypeTables)>

Translate a wasm module using this environment.

This consumes the ModuleEnvironment and produces a list of ModuleTranslations as well as a TypeTables. The list of module translations corresponds to all wasm modules found in the input data. Note that for MVP modules this will always be a list with one element, but with the module linking proposal this may have many elements.

For the module linking proposal the top-level module is returned as the first return value.

The TypeTables structure returned contains intern’d versions of types referenced from each module translation. This primarily serves as the source of truth for module-linking use cases where modules can refer to other module’s types. All SignatureIndex, ModuleTypeIndex, and InstanceTypeIndex values are resolved through the returned tables.

Trait Implementations

impl<'data> ModuleEnvironment<'data> for ModuleEnvironment<'data>

This trait is useful for translate_module because it tells how to translate environment-dependent wasm instructions. These functions should not be called by the user.

fn reserve_types(&mut self, num: u32) -> WasmResult<()>

Provides the number of types up front. By default this does nothing, but implementations can use this to preallocate memory if desired.

fn declare_type_func(&mut self, wasm: WasmFuncType) -> WasmResult<()>

Declares a function signature to the environment.

fn declare_type_module(
    &mut self,
    declared_imports: &[(&'data str, Option<&'data str>, EntityType)],
    exports: &[(&'data str, EntityType)]
) -> WasmResult<()>

Declares a module type signature to the environment.

fn declare_type_instance(
    &mut self,
    exports: &[(&'data str, EntityType)]
) -> WasmResult<()>

Declares an instance type signature to the environment.

fn type_to_signature(&self, index: TypeIndex) -> WasmResult<SignatureIndex>

Translates a type index to its signature index, only called for type indices which point to functions.

fn type_to_module_type(&self, index: TypeIndex) -> WasmResult<ModuleTypeIndex>

Translates a type index to its module type index, only called for type indices which point to modules.

fn type_to_instance_type(
    &self,
    index: TypeIndex
) -> WasmResult<InstanceTypeIndex>

Translates a type index to its instance type index, only called for type indices which point to instances.

fn reserve_imports(&mut self, num: u32) -> WasmResult<()>

Provides the number of imports up front. By default this does nothing, but implementations can use this to preallocate memory if desired.

fn declare_func_import(
    &mut self,
    index: TypeIndex,
    module: &'data str,
    field: Option<&'data str>
) -> WasmResult<()>

Declares a function import to the environment.

fn declare_table_import(
    &mut self,
    table: Table,
    module: &'data str,
    field: Option<&'data str>
) -> WasmResult<()>

Declares a table import to the environment.

fn declare_memory_import(
    &mut self,
    memory: Memory,
    module: &'data str,
    field: Option<&'data str>
) -> WasmResult<()>

Declares a memory import to the environment.

fn declare_global_import(
    &mut self,
    global: Global,
    module: &'data str,
    field: Option<&'data str>
) -> WasmResult<()>

Declares a global import to the environment.

fn declare_module_import(
    &mut self,
    ty_index: TypeIndex,
    module: &'data str,
    field: Option<&'data str>
) -> WasmResult<()>

Declares a module import to the environment.

fn declare_instance_import(
    &mut self,
    ty_index: TypeIndex,
    module: &'data str,
    field: Option<&'data str>
) -> WasmResult<()>

Declares an instance import to the environment.

fn reserve_func_types(&mut self, num: u32) -> WasmResult<()>

Provides the number of defined functions up front. By default this does nothing, but implementations can use this to preallocate memory if desired.

fn declare_func_type(&mut self, index: TypeIndex) -> WasmResult<()>

Declares the type (signature) of a local function in the module.

fn reserve_tables(&mut self, num: u32) -> WasmResult<()>

Provides the number of defined tables up front. By default this does nothing, but implementations can use this to preallocate memory if desired.

fn declare_table(&mut self, table: Table) -> WasmResult<()>

Declares a table to the environment.

fn reserve_memories(&mut self, num: u32) -> WasmResult<()>

Provides the number of defined memories up front. By default this does nothing, but implementations can use this to preallocate memory if desired.

fn declare_memory(&mut self, memory: Memory) -> WasmResult<()>

Declares a memory to the environment

fn reserve_globals(&mut self, num: u32) -> WasmResult<()>

Provides the number of defined globals up front. By default this does nothing, but implementations can use this to preallocate memory if desired.

fn declare_global(&mut self, global: Global) -> WasmResult<()>

Declares a global to the environment.

fn reserve_exports(&mut self, num: u32) -> WasmResult<()>

Provides the number of exports up front. By default this does nothing, but implementations can use this to preallocate memory if desired.

fn declare_func_export(
    &mut self,
    func_index: FuncIndex,
    name: &str
) -> WasmResult<()>

Declares a function export to the environment.

fn declare_table_export(
    &mut self,
    table_index: TableIndex,
    name: &str
) -> WasmResult<()>

Declares a table export to the environment.

fn declare_memory_export(
    &mut self,
    memory_index: MemoryIndex,
    name: &str
) -> WasmResult<()>

Declares a memory export to the environment.

fn declare_global_export(
    &mut self,
    global_index: GlobalIndex,
    name: &str
) -> WasmResult<()>

Declares a global export to the environment.

fn declare_module_export(
    &mut self,
    index: ModuleIndex,
    name: &str
) -> WasmResult<()>

Declares an instance export to the environment.

fn declare_instance_export(
    &mut self,
    index: InstanceIndex,
    name: &str
) -> WasmResult<()>

Declares an instance export to the environment.

fn declare_start_func(&mut self, func_index: FuncIndex) -> WasmResult<()>

Declares the optional start function.

fn reserve_table_elements(&mut self, num: u32) -> WasmResult<()>

Provides the number of element initializers up front. By default this does nothing, but implementations can use this to preallocate memory if desired.

fn declare_table_elements(
    &mut self,
    table_index: TableIndex,
    base: Option<GlobalIndex>,
    offset: u32,
    elements: Box<[FuncIndex]>
) -> WasmResult<()>

Fills a declared table with references to functions in the module.

fn declare_passive_element(
    &mut self,
    elem_index: ElemIndex,
    segments: Box<[FuncIndex]>
) -> WasmResult<()>

Declare a passive element segment.

fn declare_elements(&mut self, segments: Box<[FuncIndex]>) -> WasmResult<()>

Indicates that a declarative element segment was seen in the wasm module.

fn reserve_function_bodies(&mut self, _count: u32, offset: u64)

Indicates how many functions the code section reports and the byte offset of where the code sections starts.

fn define_function_body(
    &mut self,
    validator: FuncValidator<ValidatorResources>,
    body: FunctionBody<'data>
) -> WasmResult<()>

Provides the contents of a function body.

fn reserve_data_initializers(&mut self, num: u32) -> WasmResult<()>

Provides the number of data initializers up front. By default this does nothing, but implementations can use this to preallocate memory if desired.

fn declare_data_initialization(
    &mut self,
    memory_index: MemoryIndex,
    base: Option<GlobalIndex>,
    offset: u32,
    data: &'data [u8]
) -> WasmResult<()>

Fills a declared memory with bytes at module instantiation.

fn reserve_passive_data(&mut self, _count: u32) -> WasmResult<()>

Provides the number of passive data segments up front.

fn declare_passive_data(
    &mut self,
    data_index: DataIndex,
    data: &'data [u8]
) -> WasmResult<()>

Declare a passive data segment.

fn declare_module_name(&mut self, name: &'data str)

Declares the name of a module to the environment.

fn declare_func_name(&mut self, func_index: FuncIndex, name: &'data str)

Declares the name of a function to the environment.

fn declare_local_name(
    &mut self,
    func_index: FuncIndex,
    local: u32,
    name: &'data str
)

Declares the name of a function’s local to the environment.

fn custom_section(
    &mut self,
    name: &'data str,
    data: &'data [u8]
) -> WasmResult<()>

Indicates that a custom section has been found in the wasm file

fn wasm_features(&self) -> WasmFeatures

Returns the list of enabled wasm features this translation will be using.

fn reserve_modules(&mut self, amount: u32)

Indicates that this module will have amount submodules.

fn module_start(&mut self)

Called at the beginning of translating a module.

fn module_end(&mut self)

Called at the end of translating a module.

fn reserve_instances(&mut self, amt: u32)

Indicates that this module will have amount instances.

fn declare_instance(
    &mut self,
    module: ModuleIndex,
    args: Vec<(&'data str, EntityIndex)>
) -> WasmResult<()>

Declares a new instance which this module will instantiate before it’s instantiated.

fn declare_alias(&mut self, alias: Alias<'_>) -> WasmResult<()>

Declares a new alias being added to this module.

fn declare_event_import(
    &mut self,
    event: Event,
    module: &'data str,
    field: Option<&'data str>
) -> Result<(), WasmError>

Declares an event import to the environment.

fn finish_imports(&mut self) -> Result<(), WasmError>

Notifies the implementation that all imports have been declared.

fn reserve_events(&mut self, _num: u32) -> Result<(), WasmError>

Provides the number of defined events up front. By default this does nothing, but implementations can use this to preallocate memory if desired.

fn declare_event(&mut self, event: Event) -> Result<(), WasmError>

Declares an event to the environment

fn declare_event_export(
    &mut self,
    event_index: EventIndex,
    name: &'data str
) -> Result<(), WasmError>

Declares an event export to the environment.

fn finish_exports(&mut self) -> Result<(), WasmError>

Notifies the implementation that all exports have been declared.

impl<'data> TargetEnvironment for ModuleEnvironment<'data>

fn target_config(&self) -> TargetFrontendConfig

Get the information needed to produce Cranelift IR for the given target.

fn reference_type(&self, ty: WasmType) -> Type

Get the Cranelift reference type to use for the given Wasm reference type.

fn pointer_type(&self) -> Type

Get the Cranelift integer type to use for native pointers.

fn pointer_bytes(&self) -> u8

Get the size of a native pointer, in bytes.