Optimizing RISC-V Custom Instructions with Software Driven Analysis and Profiling

on YouTube ↗30m

" summary

Imperas simulation environment profiles a ChaCha20-style C workload (about 2 billion instructions executed) using instruction-accurate runs and cycle-approximate timing; adding four RISC‑V custom opcodes implemented via the Morph API replaces C sequences, reduces wall time from ~20s to ~7s (and to ~9s with a modeled 2‑cycle latency), and cuts the hot process_line 14% of total time while supporting tracing, source-level debug, coverage and per-instruction profiling.

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" chapters (5)

1. 0:00Introduction to Imperas tools
2. 5:15Demo walkthrough begins
3. 15:42Analyzing custom instructions
4. 20:02Implementation in full fabric
5. 29:10Summary and key takeaways

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