Struct wasmer_vm::InstanceAllocator
source · pub struct InstanceAllocator { /* private fields */ }
Expand description
This is an intermediate type that manages the raw allocation and
metadata when creating an [Instance
].
This type will free the allocated memory if it’s dropped before being used.
It is important to remind that [Instance
] is dynamically-sized
based on VMOffsets
: The Instance.vmctx
field represents a
dynamically-sized array that extends beyond the nominal end of the
type. So in order to create an instance of it, we must:
- Define the correct layout for
Instance
(size and alignment), - Allocate it properly.
The InstanceAllocator::instance_layout
computes the correct
layout to represent the wanted [Instance
].
Then we use this layout to allocate an empty Instance
properly.
Implementations§
source§impl InstanceAllocator
impl InstanceAllocator
sourcepub fn new(
module: &ModuleInfo
) -> (Self, Vec<NonNull<VMMemoryDefinition>>, Vec<NonNull<VMTableDefinition>>)
pub fn new( module: &ModuleInfo ) -> (Self, Vec<NonNull<VMMemoryDefinition>>, Vec<NonNull<VMTableDefinition>>)
Allocates instance data for use with VMInstance::new
.
Returns a wrapper type around the allocation and 2 vectors of
pointers into the allocated buffer. These lists of pointers
correspond to the location in memory for the local memories and
tables respectively. These pointers should be written to before
calling VMInstance::new
.