Babysitter Register Allocation

Expert skill for register allocation algorithms including graph coloring, linear scan, and spill code generation

install

source · Clone the upstream repo

git clone https://github.com/a5c-ai/babysitter

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/a5c-ai/babysitter "$T" && mkdir -p ~/.claude/skills && cp -r "$T/library/specializations/programming-languages/skills/register-allocation" ~/.claude/skills/a5c-ai-babysitter-register-allocation && rm -rf "$T"

manifest: library/specializations/programming-languages/skills/register-allocation/SKILL.md

Register Allocation Skill

Overview

Expert skill for register allocation algorithms including graph coloring, linear scan, and spill code generation.

Capabilities

Implement graph coloring register allocation
Implement linear scan register allocation
Generate spill code with minimal overhead
Handle calling convention register constraints
Implement register coalescing
Handle pre-colored nodes and fixed registers
Implement live range splitting
Design register pressure analysis

Target Processes

jit-compiler-development.js
code-generation-llvm.js
bytecode-vm-implementation.js

Dependencies

None (algorithmic skill)

Usage Guidelines

Algorithm Selection: Use linear scan for JIT (fast), graph coloring for AOT (optimal)
Live Ranges: Compute accurate live ranges before allocation
Spill Costs: Use heuristics to minimize spill costs (loop depth, usage frequency)
Calling Conventions: Handle caller/callee-saved registers correctly
Coalescing: Implement aggressive coalescing to reduce moves

Output Schema

{
  "type": "object",
  "properties": {
    "algorithm": {
      "type": "string",
      "enum": ["graph-coloring", "linear-scan", "second-chance-binpacking"]
    },
    "spillStrategy": { "type": "string" },
    "registerClasses": {
      "type": "array",
      "items": { "type": "string" }
    },
    "generatedFiles": {
      "type": "array",
      "items": { "type": "string" }
    }
  }
}