Ocelot: Open Source Vector Unit
summary
Ocelot is an open source RVV 1.0 compliant vector unit implemented in Chisel and integrated with BOOM/Chipyard, released on Tenstorrent’s GitHub and exercised with TT whisper instruction set simulator and a DV kit that runs thousands of arch and microarch tests. It supports SEW 8/16/32/64 and VLEN up to 512, is synthesized for an advanced node and targets ~1–1.2 GHz. Current limits: no div/rem/sqrt, exceptions are software-handled, single load/store pipe, no data forwarding; enabling unit-stride bulk loads yields ~2× average speedups.
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chapters (8)
- 0:00Intro
- 1:05Motivation
- 4:40Vector Unit Pipeline
- 7:37Vector FP Datapath
- 9:46Vector Unit Datapath Latencies
- 12:17Ocelot Verification
- 13:53Performance Results
- 16:45Takeaways
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