T0b1/wasmtime
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

wasmtime: Implement global.{get,set} for externref globals (#1969)

Browse Source 
* wasmtime: Implement `global.{get,set}` for externref globals

We use libcalls to implement these -- unlike `table.{get,set}`, for which we
create inline JIT fast paths -- because no known toolchain actually uses
externref globals.

Part of #929

* wasmtime: Enable `{extern,func}ref` globals in the API
This commit is contained in:
Nick Fitzgerald
2020-07-02 14:04:01 -07:00
committed by GitHub
parent 3fa3ff2ece
commit bffd54c016
19 changed files with 520 additions and 79 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
build.rs
View File

@@ -204,11 +204,7 @@ fn ignore(testsuite: &str, testname: &str, strategy: &str) -> bool {
("simd", "simd_splat") => return true, // FIXME Unsupported feature: proposed SIMD operator I32x4TruncSatF32x4S
// Still working on implementing these. See #929.
("reference_types", "global")
| ("reference_types", "linking")
| ("reference_types", "ref_func")
| ("reference_types", "ref_null")
| ("reference_types", "table_fill") => {
("reference_types", "table_fill") => {
return true;
}

108
crates/environ/src/func_environ.rs
View File

@@ -175,6 +175,10 @@ declare_builtin_functions! {
/// Returns an index to do a GC and then insert a `VMExternRef` into the
/// `VMExternRefActivationsTable`.
activations_table_insert_with_gc(vmctx, reference) -> ();
/// Returns an index for Wasm's `global.get` instruction for `externref`s.
externref_global_get(vmctx, i32) -> (reference);
/// Returns an index for Wasm's `global.get` instruction for `externref`s.
externref_global_set(vmctx, i32, reference) -> ();
}
impl BuiltinFunctionIndex {
@@ -432,6 +436,28 @@ impl<'module_environment> FuncEnvironment<'module_environment> {
new_ref_count
}
fn get_global_location(
&mut self,
func: &mut ir::Function,
index: GlobalIndex,
) -> (ir::GlobalValue, i32) {
let pointer_type = self.pointer_type();
let vmctx = self.vmctx(func);
if let Some(def_index) = self.module.defined_global_index(index) {
let offset = i32::try_from(self.offsets.vmctx_vmglobal_definition(def_index)).unwrap();
(vmctx, offset)
} else {
let from_offset = self.offsets.vmctx_vmglobal_import_from(index);
let global = func.create_global_value(ir::GlobalValueData::Load {
base: vmctx,
offset: Offset32::new(i32::try_from(from_offset).unwrap()),
global_type: pointer_type,
readonly: true,
});
(global, 0)
}
}
}
// TODO: This is necessary as if Lightbeam used `FuncEnvironment` directly it would cause
@@ -1042,19 +1068,56 @@ impl<'module_environment> cranelift_wasm::FuncEnvironment for FuncEnvironment<'m
fn translate_custom_global_get(
&mut self,
_: cranelift_codegen::cursor::FuncCursor<'_>,
_: cranelift_wasm::GlobalIndex,
mut pos: cranelift_codegen::cursor::FuncCursor<'_>,
index: cranelift_wasm::GlobalIndex,
) -> WasmResult<ir::Value> {
unreachable!("we don't make any custom globals")
debug_assert_eq!(
self.module.globals[index].wasm_ty,
WasmType::ExternRef,
"We only use GlobalVariable::Custom for externref"
);
let builtin_index = BuiltinFunctionIndex::externref_global_get();
let builtin_sig = self
.builtin_function_signatures
.externref_global_get(&mut pos.func);
let (vmctx, builtin_addr) =
self.translate_load_builtin_function_address(&mut pos, builtin_index);
let global_index_arg = pos.ins().iconst(I32, index.as_u32() as i64);
let call_inst =
pos.ins()
.call_indirect(builtin_sig, builtin_addr, &[vmctx, global_index_arg]);
Ok(pos.func.dfg.first_result(call_inst))
}
fn translate_custom_global_set(
&mut self,
_: cranelift_codegen::cursor::FuncCursor<'_>,
_: cranelift_wasm::GlobalIndex,
_: ir::Value,
mut pos: cranelift_codegen::cursor::FuncCursor<'_>,
index: cranelift_wasm::GlobalIndex,
value: ir::Value,
) -> WasmResult<()> {
unreachable!("we don't make any custom globals")
debug_assert_eq!(
self.module.globals[index].wasm_ty,
WasmType::ExternRef,
"We only use GlobalVariable::Custom for externref"
);
let builtin_index = BuiltinFunctionIndex::externref_global_set();
let builtin_sig = self
.builtin_function_signatures
.externref_global_set(&mut pos.func);
let (vmctx, builtin_addr) =
self.translate_load_builtin_function_address(&mut pos, builtin_index);
let global_index_arg = pos.ins().iconst(I32, index.as_u32() as i64);
pos.ins()
.call_indirect(builtin_sig, builtin_addr, &[vmctx, global_index_arg, value]);
Ok(())
}
fn make_heap(&mut self, func: &mut ir::Function, index: MemoryIndex) -> WasmResult<ir::Heap> {
@@ -1141,28 +1204,19 @@ impl<'module_environment> cranelift_wasm::FuncEnvironment for FuncEnvironment<'m
func: &mut ir::Function,
index: GlobalIndex,
) -> WasmResult<GlobalVariable> {
let pointer_type = self.pointer_type();
let (ptr, offset) = {
let vmctx = self.vmctx(func);
if let Some(def_index) = self.module.defined_global_index(index) {
let offset =
i32::try_from(self.offsets.vmctx_vmglobal_definition(def_index)).unwrap();
(vmctx, offset)
} else {
let from_offset = self.offsets.vmctx_vmglobal_import_from(index);
let global = func.create_global_value(ir::GlobalValueData::Load {
base: vmctx,
offset: Offset32::new(i32::try_from(from_offset).unwrap()),
global_type: pointer_type,
readonly: true,
});
(global, 0)
}
};
// Although `ExternRef`s live at the same memory location as any other
// type of global at the same index would, getting or setting them
// requires ref counting barriers. Therefore, we need to use
// `GlobalVariable::Custom`, as that is the only kind of
// `GlobalVariable` for which `cranelift-wasm` supports custom access
// translation.
if self.module.globals[index].wasm_ty == WasmType::ExternRef {
return Ok(GlobalVariable::Custom);
}
let (gv, offset) = self.get_global_location(func, index);
Ok(GlobalVariable::Memory {
gv: ptr,
gv,
offset: offset.into(),
ty: self.module.globals[index].ty,
})

27
crates/runtime/src/instance.rs
View File

@@ -29,7 +29,7 @@ use wasmtime_environ::entity::{packed_option::ReservedValue, BoxedSlice, EntityR
use wasmtime_environ::wasm::{
DataIndex, DefinedFuncIndex, DefinedGlobalIndex, DefinedMemoryIndex, DefinedTableIndex,
ElemIndex, FuncIndex, GlobalIndex, GlobalInit, MemoryIndex, SignatureIndex, TableElementType,
TableIndex,
TableIndex, WasmType,
};
use wasmtime_environ::{ir, DataInitializer, EntityIndex, Module, TableElements, VMOffsets};
@@ -226,6 +226,21 @@ impl Instance {
unsafe { self.globals_ptr().add(index) }
}
/// Get a raw pointer to the global at the given index regardless whether it
/// is defined locally or imported from another module.
///
/// Panics if the index is out of bound or is the reserved value.
pub(crate) fn defined_or_imported_global_ptr(
&self,
index: GlobalIndex,
) -> *mut VMGlobalDefinition {
if let Some(index) = self.module.local.defined_global_index(index) {
self.global_ptr(index)
} else {
self.imported_global(index).from
}
}
/// Return a pointer to the `VMGlobalDefinition`s.
fn globals_ptr(&self) -> *mut VMGlobalDefinition {
unsafe { self.vmctx_plus_offset(self.offsets.vmctx_globals_begin()) }
@@ -1390,8 +1405,16 @@ fn initialize_globals(instance: &Instance) {
};
*to = from;
}
GlobalInit::RefFunc(f) => {
*(*to).as_anyfunc_mut() = instance.get_caller_checked_anyfunc(f).unwrap()
as *const VMCallerCheckedAnyfunc;
}
GlobalInit::RefNullConst => match global.wasm_ty {
WasmType::FuncRef => *(*to).as_anyfunc_mut() = ptr::null(),
WasmType::ExternRef => *(*to).as_externref_mut() = None,
ty => panic!("unsupported reference type for global: {:?}", ty),
},
GlobalInit::Import => panic!("locally-defined global initialized as import"),
GlobalInit::RefNullConst | GlobalInit::RefFunc(_) => unimplemented!(),
}
}
}

11
crates/runtime/src/lib.rs
View File

@@ -67,3 +67,14 @@ pub fn ref_type() -> wasmtime_environ::ir::Type {
unreachable!()
}
}
/// The Cranelift IR type used for pointer types for this target architecture.
pub fn pointer_type() -> wasmtime_environ::ir::Type {
if cfg!(target_pointer_width = "32") {
wasmtime_environ::ir::types::I32
} else if cfg!(target_pointer_width = "64") {
wasmtime_environ::ir::types::I64
} else {
unreachable!()
}
}

50
crates/runtime/src/libcalls.rs
View File

@@ -60,9 +60,11 @@ use crate::externref::VMExternRef;
use crate::table::Table;
use crate::traphandlers::raise_lib_trap;
use crate::vmcontext::{VMCallerCheckedAnyfunc, VMContext};
use std::ptr::NonNull;
use std::mem;
use std::ptr::{self, NonNull};
use wasmtime_environ::wasm::{
DataIndex, DefinedMemoryIndex, ElemIndex, MemoryIndex, TableElementType, TableIndex,
DataIndex, DefinedMemoryIndex, ElemIndex, GlobalIndex, MemoryIndex, TableElementType,
TableIndex,
};
/// Implementation of f32.ceil
@@ -430,3 +432,47 @@ pub unsafe extern "C" fn wasmtime_activations_table_insert_with_gc(
let registry = &**instance.stack_map_registry();
activations_table.insert_with_gc(externref, registry);
}
/// Perform a Wasm `global.get` for `externref` globals.
pub unsafe extern "C" fn wasmtime_externref_global_get(
vmctx: *mut VMContext,
index: u32,
) -> *mut u8 {
let index = GlobalIndex::from_u32(index);
let instance = (&mut *vmctx).instance();
let global = instance.defined_or_imported_global_ptr(index);
match (*global).as_externref().clone() {
None => ptr::null_mut(),
Some(externref) => {
let raw = externref.as_raw();
let activations_table = &**instance.externref_activations_table();
let registry = &**instance.stack_map_registry();
activations_table.insert_with_gc(externref, registry);
raw
}
}
}
/// Perform a Wasm `global.set` for `externref` globals.
pub unsafe extern "C" fn wasmtime_externref_global_set(
vmctx: *mut VMContext,
index: u32,
externref: *mut u8,
) {
let externref = if externref.is_null() {
None
} else {
Some(VMExternRef::clone_from_raw(externref))
};
let index = GlobalIndex::from_u32(index);
let instance = (&mut *vmctx).instance();
let global = instance.defined_or_imported_global_ptr(index);
// Swap the new `externref` value into the global before we drop the old
// value. This protects against an `externref` with a `Drop` implementation
// that calls back into Wasm and touches this global again (we want to avoid
// it observing a halfway-deinitialized value).
let old = mem::replace((*global).as_externref_mut(), externref);
drop(old);
}

14
crates/runtime/src/sig_registry.rs
View File

@@ -65,4 +65,18 @@ impl SignatureRegistry {
pub fn lookup_wasm(&self, idx: VMSharedSignatureIndex) -> Option<WasmFuncType> {
self.index2wasm.get(&idx).cloned()
}
/// Looks up both a shared Wasm function signature and its associated native
/// `ir::Signature` within this registry.
///
/// Note that for this operation to be semantically correct the `idx` must
/// have previously come from a call to `register` of this same object.
pub fn lookup_wasm_and_native_signatures(
&self,
idx: VMSharedSignatureIndex,
) -> Option<(WasmFuncType, ir::Signature)> {
let wasm = self.lookup_wasm(idx)?;
let native = self.lookup_native(idx)?;
Some((wasm, native))
}
}

35
crates/runtime/src/vmcontext.rs
View File

@@ -1,6 +1,7 @@
//! This file declares `VMContext` and several related structs which contain
//! fields that compiled wasm code accesses directly.
use crate::externref::VMExternRef;
use crate::instance::Instance;
use std::any::Any;
use std::ptr::NonNull;
@@ -267,6 +268,7 @@ pub struct VMGlobalDefinition {
#[cfg(test)]
mod test_vmglobal_definition {
use super::VMGlobalDefinition;
use crate::externref::VMExternRef;
use more_asserts::assert_ge;
use std::mem::{align_of, size_of};
use wasmtime_environ::{Module, VMOffsets};
@@ -296,6 +298,11 @@ mod test_vmglobal_definition {
let offsets = VMOffsets::new(size_of::<*mut u8>() as u8, &module.local);
assert_eq!(offsets.vmctx_globals_begin() % 16, 0);
}
#[test]
fn check_vmglobal_can_contain_externref() {
assert!(size_of::<VMExternRef>() <= size_of::<VMGlobalDefinition>());
}
}
impl VMGlobalDefinition {
@@ -423,6 +430,30 @@ impl VMGlobalDefinition {
pub unsafe fn as_u128_bits_mut(&mut self) -> &mut [u8; 16] {
&mut *(self.storage.as_mut().as_mut_ptr() as *mut [u8; 16])
}
/// Return a reference to the value as an externref.
#[allow(clippy::cast_ptr_alignment)]
pub unsafe fn as_externref(&self) -> &Option<VMExternRef> {
&*(self.storage.as_ref().as_ptr() as *const Option<VMExternRef>)
}
/// Return a mutable reference to the value as an externref.
#[allow(clippy::cast_ptr_alignment)]
pub unsafe fn as_externref_mut(&mut self) -> &mut Option<VMExternRef> {
&mut *(self.storage.as_mut().as_mut_ptr() as *mut Option<VMExternRef>)
}
/// Return a reference to the value as an anyfunc.
#[allow(clippy::cast_ptr_alignment)]
pub unsafe fn as_anyfunc(&self) -> *const VMCallerCheckedAnyfunc {
*(self.storage.as_ref().as_ptr() as *const *const VMCallerCheckedAnyfunc)
}
/// Return a mutable reference to the value as an anyfunc.
#[allow(clippy::cast_ptr_alignment)]
pub unsafe fn as_anyfunc_mut(&mut self) -> &mut *const VMCallerCheckedAnyfunc {
&mut *(self.storage.as_mut().as_mut_ptr() as *mut *const VMCallerCheckedAnyfunc)
}
}
/// An index into the shared signature registry, usable for checking signatures
@@ -559,6 +590,10 @@ impl VMBuiltinFunctionsArray {
wasmtime_drop_externref as usize;
ptrs[BuiltinFunctionIndex::activations_table_insert_with_gc().index() as usize] =
wasmtime_activations_table_insert_with_gc as usize;
ptrs[BuiltinFunctionIndex::externref_global_get().index() as usize] =
wasmtime_externref_global_get as usize;
ptrs[BuiltinFunctionIndex::externref_global_set().index() as usize] =
wasmtime_externref_global_set as usize;
if cfg!(debug_assertions) {
for i in 0..ptrs.len() {

24
crates/wasmtime/src/externals.rs
View File

@@ -7,6 +7,8 @@ use crate::{
ValType,
};
use anyhow::{anyhow, bail, Result};
use std::mem;
use std::ptr;
use std::slice;
use wasmtime_environ::wasm;
use wasmtime_runtime::{self as runtime, InstanceHandle};
@@ -227,6 +229,15 @@ impl Global {
ValType::I64 => Val::from(*definition.as_i64()),
ValType::F32 => Val::F32(*definition.as_u32()),
ValType::F64 => Val::F64(*definition.as_u64()),
ValType::ExternRef => Val::ExternRef(
definition
.as_externref()
.clone()
.map(|inner| ExternRef { inner }),
),
ValType::FuncRef => {
from_checked_anyfunc(definition.as_anyfunc() as *mut _, &self.instance.store)
}
ty => unimplemented!("Global::get for {:?}", ty),
}
}
@@ -256,6 +267,19 @@ impl Global {
Val::I64(i) => *definition.as_i64_mut() = i,
Val::F32(f) => *definition.as_u32_mut() = f,
Val::F64(f) => *definition.as_u64_mut() = f,
Val::FuncRef(f) => {
*definition.as_anyfunc_mut() = f.map_or(ptr::null(), |f| {
f.caller_checked_anyfunc().as_ptr() as *const _
});
}
Val::ExternRef(x) => {
// In case the old value's `Drop` implementation is
// re-entrant and tries to touch this global again, do a
// replace, and then drop. This way no one can observe a
// halfway-deinitialized value.
let old = mem::replace(definition.as_externref_mut(), x.map(|x| x.inner));
drop(old);
}
_ => unimplemented!("Global::set for {:?}", val.ty()),
}
}

14
crates/wasmtime/src/func.rs
View File

@@ -10,7 +10,8 @@ use std::panic::{self, AssertUnwindSafe};
use std::ptr::{self, NonNull};
use std::rc::Weak;
use wasmtime_runtime::{
raise_user_trap, Export, InstanceHandle, VMContext, VMFunctionBody, VMTrampoline,
raise_user_trap, Export, InstanceHandle, VMContext, VMFunctionBody, VMSharedSignatureIndex,
VMTrampoline,
};
/// A WebAssembly function which can be called.
@@ -494,19 +495,20 @@ impl Func {
func.into_func(store)
}
pub(crate) fn sig_index(&self) -> VMSharedSignatureIndex {
unsafe { self.export.anyfunc.as_ref().type_index }
}
/// Returns the underlying wasm type that this `Func` has.
pub fn ty(&self) -> FuncType {
// Signatures should always be registered in the store's registry of
// shared signatures, so we should be able to unwrap safely here.
let sig = self
.instance
.store
.lookup_signature(unsafe { self.export.anyfunc.as_ref().type_index });
let wft = self.instance.store.lookup_signature(self.sig_index());
// This is only called with `Export::Function`, and since it's coming
// from wasmtime_runtime itself we should support all the types coming
// out of it, so assert such here.
FuncType::from_wasm_func_type(&sig).expect("core wasm signature should be supported")
FuncType::from_wasm_func_type(&wft).expect("core wasm signature should be supported")
}
/// Returns the number of parameters that this function takes.

11
crates/wasmtime/src/runtime.rs
View File

@@ -900,6 +900,17 @@ impl Store {
.expect("failed to lookup signature")
}
pub(crate) fn lookup_wasm_and_native_signatures(
&self,
sig_index: VMSharedSignatureIndex,
) -> (wasm::WasmFuncType, ir::Signature) {
self.inner
.signatures
.borrow()
.lookup_wasm_and_native_signatures(sig_index)
.expect("failed to lookup signature")
}
pub(crate) fn register_signature(
&self,
wasm_sig: wasm::WasmFuncType,

7
crates/wasmtime/src/trampoline/create_handle.rs
View File

@@ -7,11 +7,11 @@ use std::any::Any;
use std::collections::HashMap;
use std::sync::Arc;
use wasmtime_environ::entity::PrimaryMap;
use wasmtime_environ::wasm::DefinedFuncIndex;
use wasmtime_environ::wasm::{DefinedFuncIndex, FuncIndex};
use wasmtime_environ::Module;
use wasmtime_runtime::{
Imports, InstanceHandle, StackMapRegistry, VMExternRefActivationsTable, VMFunctionBody,
VMSharedSignatureIndex, VMTrampoline,
VMFunctionImport, VMSharedSignatureIndex, VMTrampoline,
};
pub(crate) fn create_handle(
@@ -20,9 +20,10 @@ pub(crate) fn create_handle(
finished_functions: PrimaryMap<DefinedFuncIndex, *mut [VMFunctionBody]>,
trampolines: HashMap<VMSharedSignatureIndex, VMTrampoline>,
state: Box<dyn Any>,
func_imports: PrimaryMap<FuncIndex, VMFunctionImport>,
) -> Result<StoreInstanceHandle> {
let imports = Imports::new(
PrimaryMap::new(),
func_imports,
PrimaryMap::new(),
PrimaryMap::new(),
PrimaryMap::new(),

22
crates/wasmtime/src/trampoline/func.rs
View File

@@ -3,7 +3,7 @@
use super::create_handle::create_handle;
use crate::trampoline::StoreInstanceHandle;
use crate::{FuncType, Store, Trap};
use anyhow::{bail, Result};
use anyhow::Result;
use std::any::Any;
use std::cmp;
use std::collections::HashMap;
@@ -211,10 +211,7 @@ pub fn create_handle_with_function(
let isa = store.engine().config().target_isa();
let pointer_type = isa.pointer_type();
let sig = match ft.get_wasmtime_signature(pointer_type) {
Some(sig) => sig,
None => bail!("not a supported core wasm signature {:?}", ft),
};
let sig = ft.get_wasmtime_signature(pointer_type);
let mut fn_builder_ctx = FunctionBuilderContext::new();
let mut module = Module::new();
@@ -259,6 +256,7 @@ pub fn create_handle_with_function(
finished_functions,
trampolines,
Box::new(trampoline_state),
PrimaryMap::new(),
)
.map(|instance| (instance, trampoline))
}
@@ -277,10 +275,7 @@ pub unsafe fn create_handle_with_raw_function(
};
let pointer_type = isa.pointer_type();
let sig = match ft.get_wasmtime_signature(pointer_type) {
Some(sig) => sig,
None => bail!("not a supported core wasm signature {:?}", ft),
};
let sig = ft.get_wasmtime_signature(pointer_type);
let mut module = Module::new();
let mut finished_functions = PrimaryMap::new();
@@ -298,5 +293,12 @@ pub unsafe fn create_handle_with_raw_function(
let sig_id = store.register_signature(ft.to_wasm_func_type(), sig);
trampolines.insert(sig_id, trampoline);
create_handle(module, store, finished_functions, trampolines, state)
create_handle(
module,
store,
finished_functions,
trampolines,
state,
PrimaryMap::new(),
)
}

57
crates/wasmtime/src/trampoline/global.rs
View File

@@ -1,17 +1,19 @@
use super::create_handle::create_handle;
use crate::trampoline::StoreInstanceHandle;
use crate::{GlobalType, Mutability, Store, Val};
use anyhow::{bail, Result};
use anyhow::Result;
use wasmtime_environ::entity::PrimaryMap;
use wasmtime_environ::{wasm, EntityIndex, Module};
use wasmtime_runtime::VMFunctionImport;
pub fn create_global(store: &Store, gt: &GlobalType, val: Val) -> Result<StoreInstanceHandle> {
let mut module = Module::new();
let mut func_imports = PrimaryMap::new();
let mut externref_init = None;
let global = wasm::Global {
wasm_ty: gt.content().to_wasm_type(),
ty: match gt.content().get_wasmtime_type() {
Some(t) => t,
None => bail!("cannot support {:?} as a wasm global type", gt.content()),
},
ty: gt.content().get_wasmtime_type(),
mutability: match gt.mutability() {
Mutability::Const => false,
Mutability::Var => true,
@@ -21,10 +23,42 @@ pub fn create_global(store: &Store, gt: &GlobalType, val: Val) -> Result<StoreIn
Val::I64(i) => wasm::GlobalInit::I64Const(i),
Val::F32(f) => wasm::GlobalInit::F32Const(f),
Val::F64(f) => wasm::GlobalInit::F64Const(f),
Val::ExternRef(None) | Val::FuncRef(None) => wasm::GlobalInit::RefNullConst,
Val::ExternRef(Some(x)) => {
// There is no `GlobalInit` variant for using an existing
// `externref` that isn't an import (because Wasm can't create
// an `externref` by itself). Therefore, initialize the global
// as null, and then monkey patch it after instantiation below.
externref_init = Some(x);
wasm::GlobalInit::RefNullConst
}
Val::FuncRef(Some(f)) => {
// Add a function import to the stub module, and then initialize
// our global with a `ref.func` to grab that imported function.
let shared_sig_index = f.sig_index();
let local_sig_index = module
.local
.signatures
.push(store.lookup_wasm_and_native_signatures(shared_sig_index));
let func_index = module.local.functions.push(local_sig_index);
module.local.num_imported_funcs = 1;
module
.imports
.push(("".into(), "".into(), EntityIndex::Function(func_index)));
let f = f.caller_checked_anyfunc();
let f = unsafe { f.as_ref() };
func_imports.push(VMFunctionImport {
body: f.func_ptr,
vmctx: f.vmctx,
});
wasm::GlobalInit::RefFunc(func_index)
}
_ => unimplemented!("create_global for {:?}", gt),
},
};
let mut module = Module::new();
let global_id = module.local.globals.push(global);
module
.exports
@@ -35,6 +69,17 @@ pub fn create_global(store: &Store, gt: &GlobalType, val: Val) -> Result<StoreIn
PrimaryMap::new(),
Default::default(),
Box::new(()),
func_imports,
)?;
if let Some(x) = externref_init {
match handle.lookup("global").unwrap() {
wasmtime_runtime::Export::Global(g) => unsafe {
*(*g.definition).as_externref_mut() = Some(x.inner);
},
_ => unreachable!(),
}
}
Ok(handle)
}

1
crates/wasmtime/src/trampoline/memory.rs
View File

@@ -35,6 +35,7 @@ pub fn create_handle_with_memory(
PrimaryMap::new(),
Default::default(),
Box::new(()),
PrimaryMap::new(),
)
}

1
crates/wasmtime/src/trampoline/table.rs
View File

@@ -32,5 +32,6 @@ pub fn create_handle_with_table(store: &Store, table: &TableType) -> Result<Stor
PrimaryMap::new(),
Default::default(),
Box::new(()),
PrimaryMap::new(),
)
}

34
crates/wasmtime/src/types.rs
View File

@@ -99,15 +99,15 @@ impl ValType {
}
}
pub(crate) fn get_wasmtime_type(&self) -> Option<ir::Type> {
pub(crate) fn get_wasmtime_type(&self) -> ir::Type {
match self {
ValType::I32 => Some(ir::types::I32),
ValType::I64 => Some(ir::types::I64),
ValType::F32 => Some(ir::types::F32),
ValType::F64 => Some(ir::types::F64),
ValType::V128 => Some(ir::types::I8X16),
ValType::ExternRef => Some(wasmtime_runtime::ref_type()),
_ => None,
ValType::I32 => ir::types::I32,
ValType::I64 => ir::types::I64,
ValType::F32 => ir::types::F32,
ValType::F64 => ir::types::F64,
ValType::V128 => ir::types::I8X16,
ValType::ExternRef => wasmtime_runtime::ref_type(),
ValType::FuncRef => wasmtime_runtime::pointer_type(),
}
}
@@ -248,34 +248,32 @@ impl FuncType {
}
}
/// Returns `Some` if this function signature was compatible with cranelift,
/// or `None` if one of the types/results wasn't supported or compatible
/// with cranelift.
pub(crate) fn get_wasmtime_signature(&self, pointer_type: ir::Type) -> Option<ir::Signature> {
/// Get the Cranelift-compatible function signature.
pub(crate) fn get_wasmtime_signature(&self, pointer_type: ir::Type) -> ir::Signature {
use wasmtime_environ::ir::{AbiParam, ArgumentPurpose, Signature};
use wasmtime_jit::native;
let call_conv = native::call_conv();
let mut params = self
.params
.iter()
.map(|p| p.get_wasmtime_type().map(AbiParam::new))
.collect::<Option<Vec<_>>>()?;
.map(|p| AbiParam::new(p.get_wasmtime_type()))
.collect::<Vec<_>>();
let returns = self
.results
.iter()
.map(|p| p.get_wasmtime_type().map(AbiParam::new))
.collect::<Option<Vec<_>>>()?;
.map(|p| AbiParam::new(p.get_wasmtime_type()))
.collect::<Vec<_>>();
params.insert(
0,
AbiParam::special(pointer_type, ArgumentPurpose::VMContext),
);
params.insert(1, AbiParam::new(pointer_type));
Some(Signature {
Signature {
params,
returns,
call_conv,
})
}
}
/// Returns `None` if any types in the signature can't be converted to the

70
tests/all/externals.rs
View File

@@ -111,3 +111,73 @@ fn cross_store() -> anyhow::Result<()> {
Ok(())
}
#[test]
fn get_set_externref_globals_via_api() -> anyhow::Result<()> {
let mut cfg = Config::new();
cfg.wasm_reference_types(true);
let engine = Engine::new(&cfg);
let store = Store::new(&engine);
// Initialize with a null externref.
let global = Global::new(
&store,
GlobalType::new(ValType::ExternRef, Mutability::Var),
Val::ExternRef(None),
)?;
assert!(global.get().unwrap_externref().is_none());
global.set(Val::ExternRef(Some(ExternRef::new("hello".to_string()))))?;
let r = global.get().unwrap_externref().unwrap();
assert!(r.data().is::<String>());
assert_eq!(r.data().downcast_ref::<String>().unwrap(), "hello");
// Initialize with a non-null externref.
let global = Global::new(
&store,
GlobalType::new(ValType::ExternRef, Mutability::Const),
Val::ExternRef(Some(ExternRef::new(42_i32))),
)?;
let r = global.get().unwrap_externref().unwrap();
assert!(r.data().is::<i32>());
assert_eq!(r.data().downcast_ref::<i32>().copied().unwrap(), 42);
Ok(())
}
#[test]
fn get_set_funcref_globals_via_api() -> anyhow::Result<()> {
let mut cfg = Config::new();
cfg.wasm_reference_types(true);
let engine = Engine::new(&cfg);
let store = Store::new(&engine);
let f = Func::wrap(&store, || {});
// Initialize with a null funcref.
let global = Global::new(
&store,
GlobalType::new(ValType::FuncRef, Mutability::Var),
Val::FuncRef(None),
)?;
assert!(global.get().unwrap_funcref().is_none());
global.set(Val::FuncRef(Some(f.clone())))?;
let f2 = global.get().unwrap_funcref().cloned().unwrap();
assert_eq!(f.ty(), f2.ty());
// Initialize with a non-null funcref.
let global = Global::new(
&store,
GlobalType::new(ValType::FuncRef, Mutability::Var),
Val::FuncRef(Some(f.clone())),
)?;
let f2 = global.get().unwrap_funcref().cloned().unwrap();
assert_eq!(f.ty(), f2.ty());
Ok(())
}

94
tests/all/gc.rs
View File

@@ -517,3 +517,97 @@ fn pass_externref_into_wasm_during_destructor_in_gc() -> anyhow::Result<()> {
}
}
}
#[test]
fn gc_on_drop_in_mutable_externref_global() -> anyhow::Result<()> {
let (store, module) = ref_types_module(
r#"
(module
(global $g (mut externref) (ref.null extern))
(func (export "set-g") (param externref)
(global.set $g (local.get 0))
)
)
"#,
)?;
let instance = Instance::new(&store, &module, &[])?;
let set_g = instance.get_func("set-g").unwrap();
let gc_count = Rc::new(Cell::new(0));
// Put a `GcOnDrop` into the global.
{
let args = vec![Val::ExternRef(Some(ExternRef::new(GcOnDrop {
store: store.clone(),
gc_count: gc_count.clone(),
})))];
set_g.call(&args)?;
}
// Remove the `GcOnDrop` from the `VMExternRefActivationsTable`.
store.gc();
// Overwrite the `GcOnDrop` global value, causing it to be dropped, and
// triggering a GC.
assert_eq!(gc_count.get(), 0);
set_g.call(&[Val::ExternRef(None)])?;
assert_eq!(gc_count.get(), 1);
Ok(())
}
#[test]
fn touch_own_externref_global_on_drop() -> anyhow::Result<()> {
let (store, module) = ref_types_module(
r#"
(module
(global $g (export "g") (mut externref) (ref.null extern))
(func (export "set-g") (param externref)
(global.set $g (local.get 0))
)
)
"#,
)?;
let instance = Instance::new(&store, &module, &[])?;
let g = instance.get_global("g").unwrap();
let set_g = instance.get_func("set-g").unwrap();
let touched = Rc::new(Cell::new(false));
{
let args = vec![Val::ExternRef(Some(ExternRef::new(TouchGlobalOnDrop {
g,
touched: touched.clone(),
})))];
set_g.call(&args)?;
}
// Remove the `TouchGlobalOnDrop` from the `VMExternRefActivationsTable`.
store.gc();
assert!(!touched.get());
set_g.call(&[Val::ExternRef(Some(ExternRef::new("hello".to_string())))])?;
assert!(touched.get());
return Ok(());
struct TouchGlobalOnDrop {
g: Global,
touched: Rc<Cell<bool>>,
}
impl Drop for TouchGlobalOnDrop {
fn drop(&mut self) {
// From the `Drop` implementation, we see the new global value, not
// `self`.
let r = self.g.get().unwrap_externref().unwrap();
assert!(r.data().is::<String>());
assert_eq!(r.data().downcast_ref::<String>().unwrap(), "hello");
self.touched.set(true);
}
}
}

13
tests/misc_testsuite/reference-types/mutable_externref_globals.wast Normal file
View File

@@ -0,0 +1,13 @@
;; This test contains the changes in
;; https://github.com/WebAssembly/reference-types/pull/104, and can be deleted
;; once that merges and we update our upstream tests.
(module
(global $mr (mut externref) (ref.null extern))
(func (export "get-mr") (result externref) (global.get $mr))
(func (export "set-mr") (param externref) (global.set $mr (local.get 0)))
)
(assert_return (invoke "get-mr") (ref.null extern))
(assert_return (invoke "set-mr" (ref.extern 10)))
(assert_return (invoke "get-mr") (ref.extern 10))