Add a new example file `examples/def_local_inlining.myc` to demonstrate
and test local inlining.
Refine the optimizer to handle local inlining more robustly by:
- Passing a `SubstitutionMap` to `visit_node` to track local variable
substitutions.
- Enabling constant propagation for local variables by checking
`sub.locals` in `BoundKind::Get`.
- Updating `BoundKind::DefLocal` and `BoundKind::Set` to maintain the
substitution map for local variables.
- Adjusting `try_beta_reduce` to use the optimizer's `visit_node` with
the substitution map for inlining.
- Re-indexing upvalues correctly when inlining captured variables into
lambdas.
The `is_tail` field on the `BoundKind::Call` node was an intermediate
representation for tail-call optimization and is no longer needed as a
distinct field. The TCO pass now embeds this information directly into
the `RuntimeMetadata` of the `ExecNode`, which is the VM's internal AST.
This simplifies the `BoundKind::Call` structure and removes redundant
information.
The `TailCall` variant has been merged into `Call` by adding an
`is_tail` boolean field. This simplifies the AST by reducing the number
of node variants and makes it easier to handle tail call optimization.
The `tco.rs` module is responsible for setting this flag when a call
occurs in tail position.
Implement PartialEq for BoundKind to allow for structural equality
checks during optimization. This enables the optimizer to terminate
early when a node no longer changes.
Also, implement PartialEq for Value to facilitate comparisons between
different Value variants.
The optimizer has been refactored to separate its phases and introduce
more aggressive collapsing capabilities.
Phase 2 (Cracking) now focuses on stateless transformations, making it
easier to reason about and potentially parallelize.
Phase 2.5 (Aggressive Collapsing) has been introduced, enabling
optimizations like:
- Beta-reduction for lambda literals.
- Cracking and inlining for constant closures.
- Folding intrinsics for constant arithmetic.
- Short-circuiting conditional expressions.
These changes aim to improve performance by reducing redundant
computations and code bloat. The maximum number of optimization passes
has also been increased to 5 to allow for more complex transformations.
Introduces a new optimizer pass that can "crack" closures, allowing for
more aggressive specialization. It also enables inlining of upvalues
that point to immutable global variables. This removes overhead for
higher-order functions and currying when arguments are statically
resolvable.
Michael Schimmel