Files
wasmtime/crates/runtime/src/debug_builtins.rs
Dan Gohman 9364eb1d98 Refactor (#1524)
* Compute instance exports on demand.

Instead having instances eagerly compute a Vec of Externs, and bumping
the refcount for each Extern, compute Externs on demand.

This also enables `Instance::get_export` to avoid doing a linear search.

This also means that the closure returned by `get0` and friends now
holds an `InstanceHandle` to dynamically hold the instance live rather
than being scoped to a lifetime.

* Compute module imports and exports on demand too.

And compute Extern::ty on demand too.

* Add a utility function for computing an ExternType.

* Add a utility function for looking up a function's signature.

* Add a utility function for computing the ValType of a Global.

* Rename wasmtime_environ::Export to EntityIndex.

This helps differentiate it from other Export types in the tree, and
describes what it is.

* Fix a typo in a comment.

* Simplify module imports and exports.

* Make `Instance::exports` return the export names.

This significantly simplifies the public API, as it's relatively common
to need the names, and this avoids the need to do a zip with
`Module::exports`.

This also changes `ImportType` and `ExportType` to have public members
instead of private members and accessors, as I find that simplifies the
usage particularly in cases where there are temporary instances.

* Remove `Instance::module`.

This doesn't quite remove `Instance`'s `module` member, it gets a step
closer.

* Use a InstanceHandle utility function.

* Don't consume self in the `Func::get*` methods.

Instead, just create a closure containing the instance handle and the
export for them to call.

* Use `ExactSizeIterator` to avoid needing separate `num_*` methods.

* Rename `Extern::func()` etc. to `into_func()` etc.

* Revise examples to avoid using `nth`.

* Add convenience methods to instance for getting specific extern types.

* Use the convenience functions in more tests and examples.

* Avoid cloning strings for `ImportType` and `ExportType`.

* Remove more obviated clone() calls.

* Simplify `Func`'s closure state.

* Make wasmtime::Export's fields private.

This makes them more consistent with ExportType.

* Fix compilation error.

* Make a lifetime parameter explicit, and use better lifetime names.

Instead of 'me, use 'instance and 'module to make it clear what the
lifetime is.

* More lifetime cleanups.
2020-04-20 15:55:33 -05:00

42 lines
1.4 KiB
Rust

#![doc(hidden)]
use crate::instance::InstanceHandle;
use crate::vmcontext::VMContext;
use wasmtime_environ::entity::EntityRef;
use wasmtime_environ::wasm::MemoryIndex;
static mut VMCTX_AND_MEMORY: (*mut VMContext, usize) = (std::ptr::null_mut(), 0);
#[no_mangle]
pub unsafe extern "C" fn resolve_vmctx_memory_ptr(p: *const u32) -> *const u8 {
let ptr = std::ptr::read(p);
assert!(
!VMCTX_AND_MEMORY.0.is_null(),
"must call `__vmctx->set()` before resolving Wasm pointers"
);
let handle = InstanceHandle::from_vmctx(VMCTX_AND_MEMORY.0);
assert!(
VMCTX_AND_MEMORY.1 < handle.module().local.memory_plans.len(),
"memory index for debugger is out of bounds"
);
let index = MemoryIndex::new(VMCTX_AND_MEMORY.1);
let mem = handle.instance().get_memory(index);
mem.base.add(ptr as usize)
}
#[no_mangle]
pub unsafe extern "C" fn set_vmctx_memory(vmctx_ptr: *mut VMContext) {
// TODO multi-memory
VMCTX_AND_MEMORY = (vmctx_ptr, 0);
}
// Ensures that set_vmctx_memory and resolve_vmctx_memory_ptr are linked and
// exported as symbols. It is a workaround: the executable normally ignores
// `pub extern "C"`, see rust-lang/rust#25057.
pub fn ensure_exported() {
unsafe {
std::ptr::read_volatile(resolve_vmctx_memory_ptr as *const u8);
std::ptr::read_volatile(set_vmctx_memory as *const u8);
}
}