0.3.0 – Optimizations

This release optimizes the Mica interpreter a ton, and adds the ability to call Mica functions and methods from Rust.

• #20 Sinking assignments
  • Assignments that don't result in a value now generate more efficient bytecode than previously.
  • Basically, there's now a bunch of instructions for directly popping a value off the stack into a variable without making a copy.
• #21 NaN boxing
  • Values inside the VM now take up 8 bytes instead of 24 bytes, which should improve cache efficiency.
• #24 Garbage collection
  • This is the big star of the show, and improves performance drastically by reducing branch mispredictions caused by Dropping and Cloneing values.
  • Thanks to the GC values are now trivially dropped and copied.
  • mica-hl has received an overhaul of the value API because of this and NaN boxing, because the implementation of values is now hidden and our own Gc<T> instead of Rust's Rc<T> is used.
  • There's now a Gc type in Mica's standard library, for controlling the GC's operation.
• #37 Calling Mica from Rust
  • Engine now exposes a bunch of functions that let you call any value the () call operator can be used on (right now only functions), as well as methods.
• Various smaller fixes and optimizations. In particular, a huge performance regression introduced in 0.2.0 as a result of my desperate attempts to implement reentrancy, has now been fixed.