tree 982762d33cf8624c8f68c09dfc5dbc1688133110
parent b339ed4daf668b7377134347f29a41239dee3ed6
author Kai Ninomiya <kainino@chromium.org> 1725617662 +0000
committer Dawn LUCI CQ <dawn-scoped@luci-project-accounts.iam.gserviceaccount.com> 1725617662 +0000

[emdawnwebgpu] Fix two refcounting bugs, and fix for 64-bit flags

- Ref::~Ref was calling the virtual method Release(), which for
  RefCountedWithExternalCount releases an external ref (but Ref<> is
  supposed to only be an internal ref). I stumbled on this; it did not
  actually cause any crashes, but the external refcount value was wrong.
- There was an atomic fetch_add() inside an assert(), which was skipped
  in release builds.
- Switching bitflags to 64-bit broke the Wasm->JS calling convention (in
  a very hard to find way as usual), so did the TODO that was there to
  fix it.
- Add some runtimeKeepalivePush/Pop calls for the DeviceLost callbacks.
  This seems to be the only instance of `.then()` that didn't have it.
  (I didn't actually see a crash here, I just noticed it. Note, this is
  an odd case because it may never be called, but I think this behavior
  is correct. In the future we might be able to destroy() the device
  when all of its internal and external refs reach 0? Then the
  DeviceLost callbacks should get called and the runtime can shut down.)

Discovered with and debugged/tested against this project:
https://github.com/kainino0x/webgpu-cross-platform-demo/tree/dawnwasm

Fixed: 347732150
Bug: none
Change-Id: I6cb3775b3ea7f63772cb79564e732df77c8aab68
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/205874
Auto-Submit: Kai Ninomiya <kainino@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>