@PatrickToulme: This exercise makes me believe the future of DSLs and compilers is very much agentic. Programming languages and DSLs bu…
Summary
Claude Fable used the pyptx DSL to write a FlashAttention forward kernel for NVIDIA B200 that achieves near-parity performance with the hand-tuned CUTLASS kernel, demonstrating the potential for AI agents in compiler and DSL design.
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This exercise makes me believe the future of DSLs and compilers is very much agentic. Programming languages and DSLs built for humans are not necessary for agents. Agents can handle programming languages at the bare metal level that humans are not capable of writing.
The important of proper harness engineering is also demonstrated in this task.
Patrick C Toulme (@PatrickToulme): Claude Fable wrote a FlashAttention forward kernel in pyptx DSL for the NVIDIA B200 (Blackwell) that runs at 0.92–0.99× of FlashAttention-4, the hand-tuned CUTLASS kernel — parity on two sequence lengths, ~1350 TFLOPS bf16.
It’s written in pyptx, my Python DSL that emits raw
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