Struct wasmtime_environ::Tunables

pub struct Tunables {

    pub static_memory_reservation: u64,
    pub static_memory_offset_guard_size: u64,
    pub dynamic_memory_offset_guard_size: u64,
    pub dynamic_memory_growth_reserve: u64,
    pub generate_native_debuginfo: bool,
    pub parse_wasm_debuginfo: bool,
    pub consume_fuel: bool,
    pub epoch_interruption: bool,
    pub static_memory_bound_is_maximum: bool,
    pub guard_before_linear_memory: bool,
    pub table_lazy_init: bool,
    pub generate_address_map: bool,
    pub debug_adapter_modules: bool,
    pub relaxed_simd_deterministic: bool,
    pub winch_callable: bool,
    pub signals_based_traps: bool,
}

Tunable parameters for WebAssembly compilation.

Fields

static_memory_reservation: u64

For static heaps, the size in bytes of virtual memory reservation for the heap.

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.

dynamic_memory_growth_reserve: u64

The size, in bytes, of reserved memory at the end of a “dynamic” memory, before the guard page, that memory can grow into. This is intended to amortize the cost of memory.grow in the same manner that Vec<T> has space not in use to grow into.

generate_native_debuginfo: bool

Whether or not to generate native DWARF debug information.

parse_wasm_debuginfo: bool

Whether or not to retain DWARF sections in compiled modules.

consume_fuel: bool

Whether or not fuel is enabled for generated code, meaning that fuel will be consumed every time a wasm instruction is executed.

epoch_interruption: bool

Whether or not we use epoch-based interruption.

static_memory_bound_is_maximum: bool

Whether or not to treat the static memory bound as the maximum for unbounded heaps.

guard_before_linear_memory: bool

Whether or not linear memory allocations will have a guard region at the beginning of the allocation in addition to the end.

table_lazy_init: bool

Whether to initialize tables lazily, so that instantiation is fast but indirect calls are a little slower. If false, tables are initialized eagerly from any active element segments that apply to them during instantiation.

generate_address_map: bool

Indicates whether an address map from compiled native code back to wasm offsets in the original file is generated.

debug_adapter_modules: bool

Flag for the component module whether adapter modules have debug assertions baked into them.

relaxed_simd_deterministic: bool

Whether or not lowerings for relaxed simd instructions are forced to be deterministic.

winch_callable: bool

Whether or not Wasm functions target the winch abi.

signals_based_traps: bool

Whether or not the host will be using native signals (e.g. SIGILL, SIGSEGV, etc) to implement traps.

Implementations

impl Tunables

pub fn default_host() -> Self

Returns a Tunables configuration assumed for running code on the host.

pub fn default_for_target(target: &Triple) -> Result<Self>

Returns the default set of tunables for the given target triple.

pub fn default_miri() -> Tunables

Returns the default set of tunables for running under MIRI.

pub fn default_u32() -> Tunables

Returns the default set of tunables for running under a 32-bit host.

pub fn default_u64() -> Tunables

Returns the default set of tunables for running under a 64-bit host.

Trait Implementations

impl Clone for Tunables

fn clone(&self) -> Tunables

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Tunables

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Tunables

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Hash for Tunables

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Serialize for Tunables

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.