Spill Lab
An interactive web visualizer for undergraduate compiler courses that lets students dial down the number of available registers in real kernels and watch the spill count and runtime curves diverge, mirroring the paper's findings.
second- and third-year CS students taking a compilers, computer architecture, or systems programming course
- drag-to-reserve register sliders for the GP and XMM files with live spill-count and runtime graphs from the paper's kernels
- side-by-side 'before/after' disassembly view highlighting stack-slot references added by the allocator
- instructor mode with assignment templates that ask students to predict the slowdown for a kernel and grade against measured data
- shareable lab URLs so a TA can pin a specific budget and kernel for a problem-set question
the paper's counterintuitive finding (30× spread in cost per spill) is exactly the kind of visceral teaching moment that works in a lecture, and it is fresh on Hacker News right now.
HN thread on the underlying paper only reached ~6–14 points (very low engagement for an HN item), and the niche is narrow — only a handful of universities teach a dedicated register-allocation unit; demand exists but is small.Register deprivation: spills and runtime under forced register scarcity (rjp.io) ↗Compiler Visualizer ↗
The paper's own author already shipped spillbench.rjp.io — a live, interactive 'dial-down registers' report over the same nine kernels — making it a direct competitor; add RegAlloc Studio, the IEEE ComVis web simulator, and the Vercel Compiler Visualizer, and the lane is crowded with free academic work.GitHub - rjpower/spillbench: Register deprivation: an interactive study of compiler spills and speed as GCC loses registers ↗RegAlloc Studio — Register Allocation Simulator ↗A Web-Based Educational System for Teaching Compilers (ComVis) ↗
Every comparable tool in this niche (spillbench, RegAlloc Studio, ComVis, Compiler Visualizer) is free/open-source; selling to individual students is unrealistic and university course-license sales are slow; no clear paid SKU for an interactive spill demo.GitHub - rjpower/spillbench ↗Pricing - OneCompiler ↗
Compiler and computer-architecture courses are a stable part of the CS core curriculum and register allocation is a perennial topic, so the teaching need won't fade — but neither will the free academic alternatives.A Web-Based Educational System for Teaching Compilers ↗
The author of the source paper already proved the end-to-end pipeline (gcc -ffixed-<reg> sweep + spill counting from disassembly + timing) in a small Rust/axum app; a teaching-oriented web wrapper is straightforward and low-risk.GitHub - rjpower/spillbench ↗