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JIT Compilation

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Expert skill for just-in-time compilation including profiling, tiered compilation, and deoptimization

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I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/a5c-ai/babysitter/blob/HEAD/library/specializations/programming-languages/skills/jit-compilation/SKILL.md

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JIT Compilation Skill

Overview

Expert skill for just-in-time compilation including profiling, tiered compilation, and deoptimization.

Capabilities

  • Implement execution profiling and hot path detection
  • Design tiered compilation strategies (baseline + optimizing)
  • Implement on-stack replacement (OSR)
  • Implement speculative optimizations with guards
  • Design deoptimization frame reconstruction
  • Implement inline caching and type feedback
  • Design code cache management and eviction
  • Implement method inlining heuristics

Target Processes

  • jit-compiler-development.js
  • bytecode-vm-implementation.js
  • interpreter-implementation.js

Dependencies

V8/HotSpot architecture references

Usage Guidelines

  1. Tiered Approach: Start with a baseline tier, add optimizing tier when profiling data is available
  2. Profile-Guided: Use profiling data to guide optimization decisions
  3. Speculation: Implement guards for speculative optimizations with clean deoptimization
  4. OSR: Implement OSR for long-running loops to benefit from optimization mid-execution
  5. Code Cache: Implement code cache management to handle memory pressure

Output Schema

{
  "type": "object",
  "properties": {
    "tiers": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "name": { "type": "string" },
          "trigger": { "type": "string" }
        }
      }
    },
    "profilingMethod": {
      "type": "string",
      "enum": ["counters", "sampling", "tracing"]
    },
    "osrSupport": { "type": "boolean" },
    "generatedFiles": {
      "type": "array",
      "items": { "type": "string" }
    }
  }
}