Julia Native Compilation Caching Plan

Motivating Idea:

• The standard way of using Julia would benefit from native code caching
• Other than reduced latency this should not change how you interact with the system

Approach:

• Compile a shared library to lifecycle with each ji file including
  • a format version, because implementations usually change over time
  • a linking table
  • list of external references by signature
    • runtime linker resolves each to a live address for the linking table
  • signature list of included native functions
    • runtime linker translates each to an address to put in a _jl_code_instance_t
  • the native compiled functions
    • compiled such that external references are indirect via the linking table
  • signatures will probably need to include some form of relevant world age ranges

Questions:

• What needs changed in the above proposal?
• How do the above pieces need to interact with the garbage collector?
• How can we collect the necessary signatures during the compilation process?
• How do the signatures need to be serialized to the shared library?
• How can we resolve the signatures to live addresses from the running system?
• How can we cause the native compilation to use indirection through a linking table?