Struct wasmtime_runtime::VMMemoryDefinition

#[repr(C)]
pub struct VMMemoryDefinition {
    pub base: *mut u8,
    pub current_length: AtomicUsize,
}

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.

Fields

base: *mut u8

The start address.

current_length: AtomicUsize

The current logical size of this linear memory in bytes.

This is atomic because shared memories must be able to grow their length atomically. For relaxed access, see VMMemoryDefinition::current_length().

Implementations

impl VMMemoryDefinition

pub fn current_length(&self) -> usize

Return the current length of the VMMemoryDefinition by performing a relaxed load; do not use this function for situations in which a precise length is needed. Owned memories (i.e., non-shared) will always return a precise result (since no concurrent modification is possible) but shared memories may see an imprecise value–a current_length potentially smaller than what some other thread observes. Since Wasm memory only grows, this under-estimation may be acceptable in certain cases.

pub unsafe fn load(ptr: *mut Self) -> Self

Return a copy of the VMMemoryDefinition using the relaxed value of current_length; see VMMemoryDefinition::current_length().

Trait Implementations

impl Debug for VMMemoryDefinition

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

Formats the value using the given formatter.