fluencelabs/wasm-bindgen
1
0
Fork 0
mirror of https://github.com/fluencelabs/wasm-bindgen synced 2025-06-14 05:21:24 +00:00
Code Issues Projects Releases Wiki Activity

Communicate exceptions through global memory

Browse Source 
Instead of allocating space on the stack and returning a pointer we
should be able to use a single global memory location to communicate
this error payload information. This shouldn't run into any reentrancy
issues since it's only stored just before returning to wasm and it's
always read just after returning from wasm.
This commit is contained in:
Alex Crichton
2019-06-11 11:39:48 -07:00
parent 535aa3193c
commit 6796bc6895
4 changed files with 35 additions and 39 deletions
Download Patch File Download Diff File Expand all files Collapse all files

23
crates/backend/src/codegen.rs
View File

@ -974,28 +974,12 @@ impl TryToTokens for ast::ImportFunction {
}
let mut exceptional_ret = quote!();
let exn_data = if self.catch {
let exn_data = Ident::new("exn_data", Span::call_site());
let exn_data_ptr = Ident::new("exn_data_ptr", Span::call_site());
abi_argument_names.push(exn_data_ptr.clone());
abi_arguments.push(quote! { #exn_data_ptr: *mut u32 });
if self.catch {
convert_ret = quote! { Ok(#convert_ret) };
exceptional_ret = quote! {
if #exn_data[0] == 1 {
return Err(
<
wasm_bindgen::JsValue as wasm_bindgen::convert::FromWasmAbi
>::from_abi(#exn_data[1], &mut wasm_bindgen::convert::GlobalStack::new())
)
}
wasm_bindgen::__rt::take_last_exception()?;
};
quote! {
let mut #exn_data = [0; 2];
let #exn_data_ptr = #exn_data.as_mut_ptr();
}
} else {
quote!()
};
}
let rust_name = &self.rust_name;
let import_name = &self.shim;
@ -1055,7 +1039,6 @@ impl TryToTokens for ast::ImportFunction {
#extern_fn
unsafe {
#exn_data
let #ret_ident = {
let mut __stack = wasm_bindgen::convert::GlobalStack::new();
#(#arg_conversions)*