Refactor tuples into typed opcode subclasses

[bertysentry]

Summary

• Replace the monolithic Tuple storage model with typed tuple subclasses tailored to each opcode or opcode group.
• Update AwkTuples, PositionTracker, and AVM to construct and consume the new tuple types with named accessors.
• Reduce tuple heap footprint and remove fragile positional operand access.
• Extract several larger opcode bodies out of executeTuples() to keep the dispatch loop smaller and friendlier to JIT optimization.
• Add/update tuple optimization coverage in AwkTupleOptimizationTest.

Testing

• mvn test passed.
• mvn verify passed; the existing compatibility-suite failures remain expected and unchanged.
• Local mandelbrot profiling and wall-clock checks showed the refactor no longer regresses performance and now outperforms the 6.3.00 baseline in the same WSL setup.

[Copilot]

Pull request overview

This PR refactors Jawk’s intermediate “tuple” instruction stream from a monolithic, positional-operand Tuple representation into typed opcode-specific tuple subclasses, and updates the execution/optimization code paths to use named accessors. This reduces reliance on fragile operand indexing and supports a smaller, more JIT-friendly dispatch loop in the AVM.

Changes:

• Introduces Tuple as a typed instruction hierarchy (e.g., PushLongTuple, AddressTuple, VariableTuple, etc.) and updates tuple construction accordingly.
• Updates PositionTracker and AVM to consume typed tuples via PositionTracker.current() and new accessors, extracting larger opcode bodies into helper methods.
• Updates tuple optimization tests and peephole optimization logic to work with typed tuples and new index access (currentIndex()).

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/test/java/io/jawk/AwkTupleOptimizationTest.java	Updates tuple optimization assertions to use typed tuples and a typed literal extractor.
src/main/java/io/jawk/intermediate/Tuple.java	Replaces the monolithic tuple storage with a typed tuple class hierarchy and named accessors.
src/main/java/io/jawk/intermediate/PositionTracker.java	Removes positional operand accessors and exposes the current typed tuple plus currentIndex().
src/main/java/io/jawk/intermediate/AwkTuples.java	Updates tuple emission and peephole folding to construct/inspect typed tuples.
src/main/java/io/jawk/backend/AVM.java	Switches execution to typed tuple casts/accessors and extracts several opcode implementations into helpers.

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated no new comments.