Skip to content

Support synchronous execution "concurrently" with ASYNCIFY asynchronous execution (#9412) #9423

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
kripken merged 4 commits into from
Sep 17, 2019
Merged

Support synchronous execution "concurrently" with ASYNCIFY asynchronous execution (#9412) #9423

Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
53ef87d
Update preamble.js
AjayP13 Sep 11, 2019
0cd5d45
Update preamble.js
AjayP13 Sep 14, 2019
2d16c41
Merge pull request #1 from emscripten-core/incoming
AjayP13 Sep 14, 2019
d12316e
Update preamble.js
AjayP13 Sep 17, 2019
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
16 changes: 10 additions & 6 deletions src/preamble.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -138,15 +138,19 @@ function ccall(ident, returnType, argTypes, args, opts) {
}
#endif
#if ASYNCIFY && WASM_BACKEND
if (typeof Asyncify === 'object' && Asyncify.currData) {
// The WASM function ran asynchronous and unwound its stack.
var asyncMode = opts && opts.async;
var runningAsync = typeof Asyncify === 'object' && Asyncify.currData;
var prevRunningAsync = typeof Asyncify === 'object' && Asyncify.asyncFinalizers.length > 0;
#if ASSERTIONS
assert(!asyncMode || !prevRunningAsync, 'Cannot have multiple async ccalls in flight at once');
#endif
if (runningAsync && !prevRunningAsync) {

@kripken kripken Sep 16, 2019

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Please add a comment here to explain, perhaps something like // Check if we started an async operation right now.

// Check if we started an async operation just now.
// If so, the WASM function ran asynchronous and unwound its stack.
// We need to return a Promise that resolves the return value
// once the stack is rewound and execution finishes.
#if ASSERTIONS
assert(opts && opts.async, 'The call to ' + ident + ' is running asynchronously. If this was intended, add the async option to the ccall/cwrap call.');
// Once the asyncFinalizers are called, asyncFinalizers gets reset to [].
// If they are not empty, then another async ccall is in-flight and not finished.
assert(Asyncify.asyncFinalizers.length === 0, 'Cannot have multiple async ccalls in flight at once');
assert(asyncMode, 'The call to ' + ident + ' is running asynchronously. If this was intended, add the async option to the ccall/cwrap call.');
#endif
return new Promise(function(resolve) {
Asyncify.asyncFinalizers.push(function(ret) {
Expand Down