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Decode every lane's mbarrier address when dropping unused TRYWAITs - #564
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drop_unused_trywaits only read the first address of each ARRIVE line, so mbarriers reached only through base_stride/base_delta lanes looked un-arrived and their TRYWAITs were dropped, deadlocking the simulator. Fixes accel-sim#561 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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Fixes #561.
drop_unused_trywaitsinpost-traces-processingcollected only the first address of each ARRIVE line. Multi-lane lines in base_stride/base_delta format carry the other lanes' mbarriers as offsets, so an mbarrier reached only through a delta lane looked un-arrived, and every TRYWAIT on it was dropped. In the #561 nvjet splitK kernel this removed all 28 TRYWAITs of rank 4's loader warp in every cluster (336 total). The loader then ran ahead, the mbarrier's pending count underflowed, and the cluster deadlocked.The pass now decodes every active lane for all three address formats. A TRYWAIT is dropped if any of its lanes names an mbarrier with no ARRIVE.
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#563 does a larger refactor that shares one address decoder between the tracer, the post-processor and the trace parser. That can land later on top of this.
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