Struct BaseTunables

pub struct BaseTunables {
    pub static_memory_bound: Pages,
    pub static_memory_offset_guard_size: u64,
    pub dynamic_memory_offset_guard_size: u64,
}

Tunable parameters for WebAssembly compilation. This is the reference implementation of the Tunables trait, used by default.

You can use this as a template for creating a custom Tunables implementation or use composition to wrap your Tunables around this one. The later approach is demonstrated in the tunables-limit-memory example.

Fields

static_memory_bound: Pages

For static heaps, the size in wasm pages of the heap protected by bounds checking.

static_memory_offset_guard_size: u64

The size in bytes of the offset guard for static heaps.

dynamic_memory_offset_guard_size: u64

The size in bytes of the offset guard for dynamic heaps.

Implementations

impl BaseTunables

pub fn for_target(target: &Target) -> BaseTunables

Get the BaseTunables for a specific Target

Trait Implementations

impl Clone for BaseTunables

fn clone(&self) -> BaseTunables

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Tunables for BaseTunables

fn memory_style(&self, memory: &MemoryType) -> MemoryStyle

Get a MemoryStyle for the provided MemoryType

fn table_style(&self, _table: &TableType) -> TableStyle

Get a TableStyle for the provided TableType.

fn create_host_memory( &self, ty: &MemoryType, style: &MemoryStyle, ) -> Result<VMMemory, MemoryError>

Create a memory owned by the host given a MemoryType and a MemoryStyle.

unsafe fn create_vm_memory( &self, ty: &MemoryType, style: &MemoryStyle, vm_definition_location: NonNull<VMMemoryDefinition>, ) -> Result<VMMemory, MemoryError>

Create a memory owned by the VM given a MemoryType and a MemoryStyle.

Safety

• vm_definition_location must point to a valid, owned VMMemoryDefinition, for example in VMContext.

fn create_host_table( &self, ty: &TableType, style: &TableStyle, ) -> Result<VMTable, String>

Create a table owned by the host given a TableType and a TableStyle.

unsafe fn create_vm_table( &self, ty: &TableType, style: &TableStyle, vm_definition_location: NonNull<VMTableDefinition>, ) -> Result<VMTable, String>

Create a table owned by the VM given a TableType and a TableStyle.

Safety

• vm_definition_location must point to a valid, owned VMTableDefinition, for example in VMContext.

fn create_global(&self, ty: GlobalType) -> Result<VMGlobal, String>

Create a global with an unset value.

unsafe fn create_memories( &self, context: &mut StoreObjects, module: &ModuleInfo, memory_styles: &PrimaryMap<MemoryIndex, MemoryStyle>, memory_definition_locations: &[NonNull<VMMemoryDefinition>], ) -> Result<PrimaryMap<LocalMemoryIndex, InternalStoreHandle<VMMemory>>, LinkError>

Allocate memory for just the memories of the current module.

unsafe fn create_tables( &self, context: &mut StoreObjects, module: &ModuleInfo, table_styles: &PrimaryMap<TableIndex, TableStyle>, table_definition_locations: &[NonNull<VMTableDefinition>], ) -> Result<PrimaryMap<LocalTableIndex, InternalStoreHandle<VMTable>>, LinkError>

Allocate memory for just the tables of the current module.

fn create_globals( &self, context: &mut StoreObjects, module: &ModuleInfo, ) -> Result<PrimaryMap<LocalGlobalIndex, InternalStoreHandle<VMGlobal>>, LinkError>

Allocate memory for just the globals of the current module, with initializers applied.

fn vmconfig(&self) -> &VMConfig

Get the VMConfig for this tunables Currently, VMConfig have optional Stack size If wasm_stack_size is left to None (the default value) then the global stack size will be use Else the defined stack size will be used. Size is in byte and the value might be rounded to sane value is needed.