Remove TODO from libpthread.js. NFC - #26603
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This TODO was added in emscripten-core#18861 when the following line read: ``` Atomics.waitAsync(HEAP32, pthread_ptr >> 2, pthread_ptr); ``` I'm not sure if the TODO here was refering to that 2nd or 3rd argument but they both work fine under wasm64 right now. The second argument now uses `getHeapOffset('pthread_ptr', 'i32')` which works find under wasm64 even for addresses over 4gb. The third argument here is actually not important since its value never changes, it just needs to match the contents of the memory at the specific location. I verified that this works in wasm64_4gb mode. The `pthread_ptr` is simply converted to a U32 and then compared to the low bits of the 64-bit pthread_ptr in memory. The assert on the line below ensure that this does indeed work. If it didn't then `"not-equal"` would be returned from `Atomics.waitAsync`
tlively
approved these changes
Apr 1, 2026
Co-authored-by: Thomas Lively <tlively123@gmail.com>
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This TODO was added in #18861 when the following line read:
I'm not sure if the TODO here was refering to that 2nd or 3rd argument but they both work fine under wasm64 right now.
The second argument now uses
getHeapOffset('pthread_ptr', 'i32')which works find under wasm64 even for addresses over 4gb.The third argument here is actually not important since its value never changes, it just needs to match the contents of the memory at the specific location. I verified that this works in wasm64_4gb mode. The
pthread_ptris simply converted to a U32 and then compared to the low bits of the 64-bit pthread_ptr in memory. The assert on the line below ensure that this does indeed work. If it didn't then"not-equal"would be returned fromAtomics.waitAsync