scratchfoundation/scratch-vm
1
0
Fork 0
mirror of https://github.com/scratchfoundation/scratch-vm.git synced 2025-08-28 22:30:40 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

Constant time check if thread is in doneThreads

Browse source 
Remove indexOf tests for thread existence in doneThreads. Maintain a
list of null and thread objects mirroring the index position of threads
that are done in runtime.threads. Filter out null values after
filtering out done threads from runtime.threads.

This has a small side effect that threads that normally became DONE and
were added to doneThreads before being removed or restarted will not be
in doneThreads in this version. Restarted threads (_restartThread) do
not appear in this version but new copies will be in Runtime
this.threads supporting glow and monitor updates. Removed threads
(_removeThread) do not appear in this version if they are removed after
they were seen as DONE by the prior version. Threads removed before
they are seen as DONE do not appear in doneThreads in the prior or this
version.

Threads that are removed before normally becoming DONE do not appear in
doneThreads in either case. Threads that are restarted before the loop
checks if the thread is done do not appear in doneThreads in either
case.
This commit is contained in:
Michael "Z" Goddard 2017-11-03 11:52:42 -04:00
parent c5d3e2dbb4
commit 4e24a3f380
No known key found for this signature in database
GPG key ID: 762CD40DD5349872
1 changed files with 9 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

16
src/engine/sequencer.js
View file

@ -38,7 +38,7 @@ class Sequencer {
let numActiveThreads = Infinity;
// Whether `stepThreads` has run through a full single tick.
let ranFirstTick = false;
const doneThreads = [];
const doneThreads = this.runtime.threads.map(() => null);
// Conditions for continuing to stepping threads:
// 1. We must have threads in the list, and some must be active.
// 2. Time elapsed must be less than WORK_TIME.
@ -54,11 +54,13 @@ class Sequencer {
if (activeThread.stack.length === 0 ||
activeThread.status === Thread.STATUS_DONE) {
// Finished with this thread.
if (doneThreads.indexOf(activeThread) < 0) {
doneThreads.push(activeThread);
}
doneThreads[i] = activeThread;
continue;
}
// A thread was removed, added or this thread was restarted.
if (doneThreads[i] !== null) {
doneThreads[i] = null;
}
if (activeThread.status === Thread.STATUS_YIELD_TICK &&
!ranFirstTick) {
// Clear single-tick yield from the last call of `stepThreads`.
@ -82,13 +84,13 @@ class Sequencer {
ranFirstTick = true;
}
// Filter inactive threads from `this.runtime.threads`.
this.runtime.threads = this.runtime.threads.filter(thread => {
if (doneThreads.indexOf(thread) > -1) {
this.runtime.threads = this.runtime.threads.filter((thread, i) => {
if (doneThreads[i] === null) {
return false;
}
return true;
});
return doneThreads;
return doneThreads.filter(Boolean);
}
/**